US20060226414A1 - Group III-V nitride-based semiconductor substrate and method of making same - Google Patents
Group III-V nitride-based semiconductor substrate and method of making same Download PDFInfo
- Publication number
- US20060226414A1 US20060226414A1 US11/176,687 US17668705A US2006226414A1 US 20060226414 A1 US20060226414 A1 US 20060226414A1 US 17668705 A US17668705 A US 17668705A US 2006226414 A1 US2006226414 A1 US 2006226414A1
- Authority
- US
- United States
- Prior art keywords
- substrate
- nitride
- group iii
- crystal
- based semiconductor
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Abandoned
Links
- 239000000758 substrate Substances 0.000 title claims abstract description 181
- 239000004065 semiconductor Substances 0.000 title claims abstract description 84
- 150000004767 nitrides Chemical class 0.000 title claims abstract description 82
- 238000004519 manufacturing process Methods 0.000 title claims abstract description 18
- 239000013078 crystal Substances 0.000 claims abstract description 137
- 238000000034 method Methods 0.000 claims description 37
- 229910052594 sapphire Inorganic materials 0.000 claims description 25
- 239000010980 sapphire Substances 0.000 claims description 25
- 239000000203 mixture Substances 0.000 claims description 22
- 239000006185 dispersion Substances 0.000 claims description 16
- 239000011800 void material Substances 0.000 claims description 9
- JMASRVWKEDWRBT-UHFFFAOYSA-N Gallium nitride Chemical compound [Ga]#N JMASRVWKEDWRBT-UHFFFAOYSA-N 0.000 description 93
- 229910002601 GaN Inorganic materials 0.000 description 61
- 238000009826 distribution Methods 0.000 description 17
- 238000002248 hydride vapour-phase epitaxy Methods 0.000 description 12
- 239000010408 film Substances 0.000 description 10
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 description 5
- 238000005498 polishing Methods 0.000 description 5
- 230000008569 process Effects 0.000 description 5
- XOYLJNJLGBYDTH-UHFFFAOYSA-M chlorogallium Chemical compound [Ga]Cl XOYLJNJLGBYDTH-UHFFFAOYSA-M 0.000 description 4
- 230000007547 defect Effects 0.000 description 4
- 239000007789 gas Substances 0.000 description 4
- 229910003818 SiH2Cl2 Inorganic materials 0.000 description 3
- 229910052799 carbon Inorganic materials 0.000 description 3
- 239000012159 carrier gas Substances 0.000 description 3
- 150000001875 compounds Chemical class 0.000 description 3
- 238000004020 luminiscence type Methods 0.000 description 3
- IJGRMHOSHXDMSA-UHFFFAOYSA-N Atomic nitrogen Chemical compound N#N IJGRMHOSHXDMSA-UHFFFAOYSA-N 0.000 description 2
- ATJFFYVFTNAWJD-UHFFFAOYSA-N Tin Chemical compound [Sn] ATJFFYVFTNAWJD-UHFFFAOYSA-N 0.000 description 2
- 238000002441 X-ray diffraction Methods 0.000 description 2
- 239000000853 adhesive Substances 0.000 description 2
- 230000001070 adhesive effect Effects 0.000 description 2
- PNEYBMLMFCGWSK-UHFFFAOYSA-N aluminium oxide Inorganic materials [O-2].[O-2].[O-2].[Al+3].[Al+3] PNEYBMLMFCGWSK-UHFFFAOYSA-N 0.000 description 2
- RNQKDQAVIXDKAG-UHFFFAOYSA-N aluminum gallium Chemical compound [Al].[Ga] RNQKDQAVIXDKAG-UHFFFAOYSA-N 0.000 description 2
- 238000005253 cladding Methods 0.000 description 2
- 238000001816 cooling Methods 0.000 description 2
- 238000007716 flux method Methods 0.000 description 2
- 229910002804 graphite Inorganic materials 0.000 description 2
- 239000010439 graphite Substances 0.000 description 2
- 230000006872 improvement Effects 0.000 description 2
- 230000001678 irradiating effect Effects 0.000 description 2
- 230000004048 modification Effects 0.000 description 2
- 238000012986 modification Methods 0.000 description 2
- 238000012360 testing method Methods 0.000 description 2
- 239000010409 thin film Substances 0.000 description 2
- GYHNNYVSQQEPJS-UHFFFAOYSA-N Gallium Chemical compound [Ga] GYHNNYVSQQEPJS-UHFFFAOYSA-N 0.000 description 1
- 229910001218 Gallium arsenide Inorganic materials 0.000 description 1
- NWAIGJYBQQYSPW-UHFFFAOYSA-N azanylidyneindigane Chemical compound [In]#N NWAIGJYBQQYSPW-UHFFFAOYSA-N 0.000 description 1
- 230000003139 buffering effect Effects 0.000 description 1
- 230000003185 calcium uptake Effects 0.000 description 1
- 239000011248 coating agent Substances 0.000 description 1
- 238000000576 coating method Methods 0.000 description 1
- 230000000052 comparative effect Effects 0.000 description 1
- 230000006835 compression Effects 0.000 description 1
- 238000007906 compression Methods 0.000 description 1
- 238000010276 construction Methods 0.000 description 1
- 238000007796 conventional method Methods 0.000 description 1
- 239000002019 doping agent Substances 0.000 description 1
- 230000002708 enhancing effect Effects 0.000 description 1
- 229910052733 gallium Inorganic materials 0.000 description 1
- 238000010438 heat treatment Methods 0.000 description 1
- 239000012535 impurity Substances 0.000 description 1
- 229910052738 indium Inorganic materials 0.000 description 1
- APFVFJFRJDLVQX-UHFFFAOYSA-N indium atom Chemical compound [In] APFVFJFRJDLVQX-UHFFFAOYSA-N 0.000 description 1
- 239000000463 material Substances 0.000 description 1
- 229910052757 nitrogen Inorganic materials 0.000 description 1
- 230000009467 reduction Effects 0.000 description 1
- 238000011160 research Methods 0.000 description 1
- 238000000926 separation method Methods 0.000 description 1
- 238000001771 vacuum deposition Methods 0.000 description 1
- 238000000927 vapour-phase epitaxy Methods 0.000 description 1
Images
Classifications
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
- H01L29/00—Semiconductor devices adapted for rectifying, amplifying, oscillating or switching, or capacitors or resistors with at least one potential-jump barrier or surface barrier, e.g. PN junction depletion layer or carrier concentration layer; Details of semiconductor bodies or of electrodes thereof ; Multistep manufacturing processes therefor
- H01L29/02—Semiconductor bodies ; Multistep manufacturing processes therefor
- H01L29/12—Semiconductor bodies ; Multistep manufacturing processes therefor characterised by the materials of which they are formed
- H01L29/20—Semiconductor bodies ; Multistep manufacturing processes therefor characterised by the materials of which they are formed including, apart from doping materials or other impurities, only AIIIBV compounds
- H01L29/2003—Nitride compounds
-
- C—CHEMISTRY; METALLURGY
- C30—CRYSTAL GROWTH
- C30B—SINGLE-CRYSTAL GROWTH; UNIDIRECTIONAL SOLIDIFICATION OF EUTECTIC MATERIAL OR UNIDIRECTIONAL DEMIXING OF EUTECTOID MATERIAL; REFINING BY ZONE-MELTING OF MATERIAL; PRODUCTION OF A HOMOGENEOUS POLYCRYSTALLINE MATERIAL WITH DEFINED STRUCTURE; SINGLE CRYSTALS OR HOMOGENEOUS POLYCRYSTALLINE MATERIAL WITH DEFINED STRUCTURE; AFTER-TREATMENT OF SINGLE CRYSTALS OR A HOMOGENEOUS POLYCRYSTALLINE MATERIAL WITH DEFINED STRUCTURE; APPARATUS THEREFOR
- C30B25/00—Single-crystal growth by chemical reaction of reactive gases, e.g. chemical vapour-deposition growth
- C30B25/02—Epitaxial-layer growth
-
- C—CHEMISTRY; METALLURGY
- C30—CRYSTAL GROWTH
- C30B—SINGLE-CRYSTAL GROWTH; UNIDIRECTIONAL SOLIDIFICATION OF EUTECTIC MATERIAL OR UNIDIRECTIONAL DEMIXING OF EUTECTOID MATERIAL; REFINING BY ZONE-MELTING OF MATERIAL; PRODUCTION OF A HOMOGENEOUS POLYCRYSTALLINE MATERIAL WITH DEFINED STRUCTURE; SINGLE CRYSTALS OR HOMOGENEOUS POLYCRYSTALLINE MATERIAL WITH DEFINED STRUCTURE; AFTER-TREATMENT OF SINGLE CRYSTALS OR A HOMOGENEOUS POLYCRYSTALLINE MATERIAL WITH DEFINED STRUCTURE; APPARATUS THEREFOR
- C30B29/00—Single crystals or homogeneous polycrystalline material with defined structure characterised by the material or by their shape
- C30B29/10—Inorganic compounds or compositions
- C30B29/40—AIIIBV compounds wherein A is B, Al, Ga, In or Tl and B is N, P, As, Sb or Bi
- C30B29/403—AIII-nitrides
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
- H01L21/00—Processes or apparatus adapted for the manufacture or treatment of semiconductor or solid state devices or of parts thereof
- H01L21/02—Manufacture or treatment of semiconductor devices or of parts thereof
- H01L21/02104—Forming layers
- H01L21/02365—Forming inorganic semiconducting materials on a substrate
- H01L21/02367—Substrates
- H01L21/0237—Materials
- H01L21/0242—Crystalline insulating materials
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
- H01L21/00—Processes or apparatus adapted for the manufacture or treatment of semiconductor or solid state devices or of parts thereof
- H01L21/02—Manufacture or treatment of semiconductor devices or of parts thereof
- H01L21/02104—Forming layers
- H01L21/02365—Forming inorganic semiconducting materials on a substrate
- H01L21/02436—Intermediate layers between substrates and deposited layers
- H01L21/02439—Materials
- H01L21/02455—Group 13/15 materials
- H01L21/02458—Nitrides
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
- H01L21/00—Processes or apparatus adapted for the manufacture or treatment of semiconductor or solid state devices or of parts thereof
- H01L21/02—Manufacture or treatment of semiconductor devices or of parts thereof
- H01L21/02104—Forming layers
- H01L21/02365—Forming inorganic semiconducting materials on a substrate
- H01L21/02518—Deposited layers
- H01L21/02521—Materials
- H01L21/02538—Group 13/15 materials
- H01L21/0254—Nitrides
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
- H01L21/00—Processes or apparatus adapted for the manufacture or treatment of semiconductor or solid state devices or of parts thereof
- H01L21/02—Manufacture or treatment of semiconductor devices or of parts thereof
- H01L21/02104—Forming layers
- H01L21/02365—Forming inorganic semiconducting materials on a substrate
- H01L21/02612—Formation types
- H01L21/02617—Deposition types
- H01L21/0262—Reduction or decomposition of gaseous compounds, e.g. CVD
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
- H01L21/00—Processes or apparatus adapted for the manufacture or treatment of semiconductor or solid state devices or of parts thereof
- H01L21/02—Manufacture or treatment of semiconductor devices or of parts thereof
- H01L21/02104—Forming layers
- H01L21/02365—Forming inorganic semiconducting materials on a substrate
- H01L21/02612—Formation types
- H01L21/02617—Deposition types
- H01L21/02636—Selective deposition, e.g. simultaneous growth of mono- and non-monocrystalline semiconductor materials
- H01L21/02639—Preparation of substrate for selective deposition
- H01L21/02642—Mask materials other than SiO2 or SiN
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
- H01L21/00—Processes or apparatus adapted for the manufacture or treatment of semiconductor or solid state devices or of parts thereof
- H01L21/02—Manufacture or treatment of semiconductor devices or of parts thereof
- H01L21/02104—Forming layers
- H01L21/02365—Forming inorganic semiconducting materials on a substrate
- H01L21/02656—Special treatments
- H01L21/02664—Aftertreatments
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
- H01L33/00—Semiconductor devices with at least one potential-jump barrier or surface barrier specially adapted for light emission; Processes or apparatus specially adapted for the manufacture or treatment thereof or of parts thereof; Details thereof
- H01L33/005—Processes
- H01L33/0062—Processes for devices with an active region comprising only III-V compounds
- H01L33/0075—Processes for devices with an active region comprising only III-V compounds comprising nitride compounds
Definitions
- This invention relates to a group III-V nitride-based semiconductor substrate and a method of making the same.
- GaN-based compound semiconductors such as gallium nitride (GaN), indium gallium nitride (InGaN) and aluminum gallium nitride (AlGaN) attract attention for a material of blue light emitting diode (LED) or laser diode (LD). Further, since the GaN-based compound semiconductors have a good heat resistance and environment resistance, they have begun to be applied to other electronic devices.
- GaN-based compound semiconductors such as gallium nitride (GaN), indium gallium nitride (InGaN) and aluminum gallium nitride (AlGaN) attract attention for a material of blue light emitting diode (LED) or laser diode (LD). Further, since the GaN-based compound semiconductors have a good heat resistance and environment resistance, they have begun to be applied to other electronic devices.
- a substrate used widely to grow GaN is sapphire.
- a method is used in which GaN is epitaxially grown on a sapphire single crystal substrate by MOVPE (metalorganic vapor phase epitaxy) etc.
- the epitaxial growth of GaN single crystal can be realized.
- the above method still has a problem that the grown GaN has a number of defects since the lattice mismatch between the substrate and the GaN is not eliminated. It is presumed that the defect brings some failure to a manufacture of GaN-based LD.
- a typical method for making a nitride semiconductor self-standing substrate is conducted such that a GaN thick film is grown on a hetero-substrate such as sapphire by HVPE and then the hetero-substrate is removed to obtain a GaN self-standing substrate (e.g., JP-A-2003-178984, herein referred to as VAS method and the entire contents of JP-A-2003-178984 are incorporated herein by reference).
- a void-containing layer functions as a strain buffering layer so as to buffer a strain caused by a difference in lattice constant or thermal expansion coefficient between the underlying substrate and the group III nitride semiconductor layer grown thereon.
- a substrate of group III nitride semiconductor can be obtained which offers a reduced defect density and a good crystalline quality without warping. Further, the self-standing substrate thus obtained can be easily separated. Based on the method, GaN substrates with a reduced dislocation have begun to be commercially available.
- the non-uniformity of crystal orientation may cause dispersion in emission wavelength since the InGaN composition of an active layer may be non-uniform.
- the non-uniformity of thickness, especially unevenness on the back surface face of the substrate causes non-uniformity of temperature distribution during growth of device epitaxial layer. This affects the InGaN composition of the active layer to cause non-uniformity in the emission wavelength.
- a group III-V nitride-based semiconductor substrate comprises;
- said substrate has a surface area of 45 cm 2 or more
- said substrate has thickness of 200 ⁇ m or more
- said substrate has an in-plane dislocation density of 2 ⁇ 10 7 cm ⁇ 2 or less in average
- the in-plane dislocation density is 150% or less of the average at maximum.
- said substrate has at a surface thereof a dispersion in crystal axis of ⁇ 0.3 degrees or less
- said substrate has at an arbitrary point of a surface thereof a carrier concentration that falls within ⁇ 20% of an average carrier concentration at the surface.
- said substrate has at an arbitrary point of a surface thereof a thickness that falls within ⁇ 10 ⁇ m from an average thickness at the surface
- said group III-V nitride-based semiconductor crystal has an FWHM value of X-ray rocking curve of 250 seconds or less.
- said group III-V nitride-based semiconductor crystal has a composition of In x Al y Ga 1-x-y N (x ⁇ 0, y ⁇ 0, x+y ⁇ 1).
- a method of making a group III-V nitride-based semiconductor substrate comprises:
- the first crystal substrate is bonded to the susceptor.
- the first crystal substrate is a hetero-substrate that has a composition different from the first group III-V nitride-based semiconductor crystal.
- the first crystal substrate is a hetero-substrate that has a composition different from the first group III-V nitride-based semiconductor crystal, and
- said method further comprising:
- said hetero-substrate is a sapphire substrate.
- the first crystal substrate is a seed crystal substrate that has the same composition as the first group III-V nitride-based semiconductor crystal.
- said first group III-V nitride-based semiconductor crystal has a composition of In x Al y Ga 1-x-y N (x ⁇ 0, y ⁇ 0, x+y ⁇ 1).
- a method of making a group III-V nitride-based semiconductor substrate comprises:
- the first crystal substrate is bonded to the susceptor.
- the first crystal substrate is a hetero-substrate that has a composition different from the first group III-V nitride-based semiconductor crystal.
- the first crystal substrate is a hetero-substrate that has a composition different from the first group III-V nitride-based semiconductor crystal, and
- said hetero-substrate is a sapphire substrate.
- the first crystal substrate is a seed crystal substrate that has the same composition as the first group III-V nitride-based semiconductor crystal.
- said first group III-V nitride-based semiconductor crystal has a composition of In x Al y Ga 1-x-y N (x ⁇ 0, y ⁇ 0, x+y ⁇ 1).
- the invention is featured in that, in the growth of nitride semiconductor by HVPE (hydride vapor phase epitaxy), temperature of crystal during the growth is kept uniform to make the growth speed and impurity concentration uniform. Thereby, various properties such as dislocation density to be varied therewith can be significantly enhanced.
- HVPE hydrogen vapor phase epitaxy
- the non-uniformity in growth temperature causes non-uniformity in growth speed.
- the hetero-epitaxial growth of GaN proceeds generally in the Volmer-Weber type growth manner, wherein a number of growth initial nuclei are generated, they are bonded to each other as the growth progresses, and it is finally transited into two-dimensional growth. If the growth speed is varied, a nucleus generation density at initial growth and the subsequent planarization behavior are varied and, thereby, a dislocation density at final surface is varied. Furthermore, if the growth speed is varied, a dopant introduction density is also varied, which causes non-uniformity in carrier concentration and electrical resistivity.
- the in-plane polishing speed may be non-uniform due to a difference in dislocation density or carrier concentration and, thereby, the final thickness may be non-uniform.
- the non-uniformity in growth temperature causes a warp in crystal.
- the in-plane dispersion of crystal axes may be increased.
- the crystal growth of GaN is conducted placing a seed substrate on a black-body susceptor of graphite or SiC. Since the GaN or sapphire has a transparent body, the heating of substrate is conducted mainly by thermal conduction through the susceptor. Thus, it is important to keep the substrate uniformly in contact with the susceptor.
- the substrate is significantly warped during growth and the thermal contact therebetween may be therefore non-uniform.
- the growth of GaN on a hetero-epitaxial substrate such as sapphire, as described earlier, proceeds generally in the Volmer-Weber type growth manner, where the initial growth nucleus attract each other so as to minimize the surface energy when being combined each together and, as a result, a tensile stress must be generated.
- the thickness of the growth film is sufficiently thin as compared to the thickness of the underlying substrate.
- the thickness of the growth film is equal to or greater than the underlying substrate, a large warping is generated such that it can seriously affect the thermal distribution of the in-plane growth substrate.
- (D) its in-plane dispersion of thickness is ⁇ 10 ⁇ m or less of an average value.
- a substrate of the invention Using a substrate of the invention, a device epitaxial layer with a large surface area can be fabricated in a high uniformity. Therefore, it is very advantageous in economical aspect.
- the in-plane non-uniformity of the substrate properties caused by the non-uniformity of the growth temperature can be eliminated.
- a group III-V nitride semiconductor substrate can be obtained with a high quality and a high uniformity.
- FIGS. 1A to 1 E are illustrative cross sectional views showing of a method of making a group III-V nitride semiconductor substrate in a first preferred embodiment according to the invention
- FIGS. 2A to 2 E are illustrative cross sectional views showing of a method of making a group III-V nitride semiconductor substrate in a second preferred embodiment according to the invention.
- FIGS. 3A to 3 E are illustrative cross sectional views showing a conventional method of making a group III-V nitride semiconductor substrate
- FIGS. 3A to 3 E For the sake of comparison, a conventional example will be first explained below referring to FIGS. 3A to 3 E.
- FIG. 3C a Si-doped GaN thick film 3 is grown ( FIG. 3C ).
- SiH 2 Cl 2 gas is flown at partial pressure of 5 ⁇ 10 ⁇ 4 atm. Growth temperature is 1070° C.
- the resultant GaN crystal (i.e., GaN thick film 3 ) has a thickness of 800 ⁇ m at the central portion and 500 ⁇ m at the outermost portion. Thus, it has a significant distribution in thickness.
- a GaN substrate 4 is separated decomposing a GaN crystal at the interface ( FIG. 3D ).
- the GaN substrate 4 separated is warped in the form of a concave, whose curvature radius is about 3 meters.
- a 3-inch GaN self-standing substrate 5 with a thickness of 430 ⁇ m at the central portion is obtained ( FIG. 3E ). However, it has a highly reduced thickness of 400 ⁇ m at the outermost portion.
- the dislocation density is 2 ⁇ 10 7 cm ⁇ 2 at the outermost portion while it is 1 ⁇ 10 7 cm ⁇ 2 at the central portion.
- the carrier concentration is 3 ⁇ 10 18 cm ⁇ 3 at the outermost portion while it is 1 ⁇ 10 18 cm ⁇ 3 at the central portion. It is presumed that these distributions are caused by that the in-plane distribution of growth speed is large. That the polishing rate is faster at the outer portion of the substrate and the thickness of the outer portion is thus reduced may be affected by the non-uniformity of the dislocation density and the carrier concentration.
- the c-axis is inclined as much as about ⁇ 0.7 to the center of the substrate. This inclination may be generated because of directly polishing the warped substrate.
- a blue LED is epitaxially grown by MOVPE. Its active layer is formed in multiauantum well structure of InGaN/AlGaN and is sandwiched by AlGaN cladding layers.
- the emission wavelength of the obtained LED is highly dispersed as 405 ⁇ 15 nm, and 90% of the entire area of the epitaxial wafer does not meet the standard. This is because the crystal orientation of the GaN substrate used is not uniform and, therefore, the composition of InGaN in the active layer is dispersed in plane.
- about 10% of samples have a life less than 10000 hours in high output operation at 1 W. This may be caused by a local region with a high dislocation density.
- FIGS. 1A to 1 E are illustrative cross sectional views showing of a method of making a group III-V nitride semiconductor substrate in the first preferred embodiment according to the invention.
- FIG. 1C a Si-doped GaN thick film 8 is grown ( FIG. 1C ).
- SiH 2 Cl 2 gas is flown at partial pressure of 5 ⁇ 10 ⁇ 4 atm. Growth temperature is 1070° C.
- a GaN substrate 9 is separated decomposing a GaN crystal at the interface ( FIG. 1D ).
- the resultant GaN crystal (i.e., GaN thick film 8 ) has a thickness of 800 ⁇ m at the central portion and 700 ⁇ m at the outermost portion. Thus, it has an improved distribution in thickness.
- the GaN substrate 9 separated has a curvature radius of about 10 meters, where the warping is significantly improved. This is because of using the thick sapphire substrate 6 .
- the improvement of thickness distribution maybe caused such that the warping during growth is reduced, the uniform contact with the susceptor (not shown) is thereby obtained and the growth temperature becomes uniform in plane.
- Both faces of the GaN substrate 9 are polished ( FIG. 1E ) Because of the improved thickness distribution and warping, though it has a reduced growth thickness, by polishing both faces of the substrate, a 3-inch GaN self-standing substrate 10 with a uniform thickness of 430 ⁇ m can be obtained.
- the dislocation density is 1.4 ⁇ 10 7 cm ⁇ 2 at the outermost portion while it is 1 ⁇ 10 7 cm ⁇ 2 at the central portion.
- the carrier concentration is 1.3 ⁇ 10 18 cm ⁇ 3 at the outermost portion while it is 1 ⁇ 10 18 cm ⁇ 3 at the central portion.
- the c-axis is inclined about ⁇ 0.21.
- an about 1 ⁇ m thick carbon layer is formed on the back face of the sapphire substrate 6 and then the HVPE growth is conducted in like manner. Thereby, the temperature distribution during growth can be further improved
- the thickness distribution as grown is 800 ⁇ m at the central portion and 750 ⁇ m at the outermost portion,
- the properties of the GaN substrate are also improved.
- the dislocation density is 1 ⁇ 10 7 cm ⁇ 2 both at the central portion and at the outermost portion
- the carrier concentration is 1 ⁇ 10 18 cm ⁇ 3 both at the central portion and at the outermost portion.
- the c-axis is inclined about ⁇ 0.18.
- FIGS. 2A to 2 E are illustrative cross sectional views showing of a method of making a group III-V nitride semiconductor substrate in the third preferred embodiment according to the invention.
- a 20 nm thick Ti layer is formed thereon in vacuum deposition.
- carrier gas of H 2 :NH 3 4:1 at 1060° C. for 30 min.
- the Ti layer is nitrided into a TiN layer and formed into mesh-like structure (i.e., TiN nano-mask 11 ) with a number of fine holes of tens of nanometers.
- the GaN underlying layer 17 is etched to have therein voids reaching up to the sapphire substrate 6 ( FIG. 2B ).
- the void-formed substrate is placed in the HVPE furnace while being bonded through an alumina-based high-temperature adhesive 12 to the graphite susceptor (not shown) ( FIG. 2C ).
- the growth pressure and temperature are atmospheric pressure and 1040° C.
- SiH 2 Cl 2 gas is flown at partial pressure of 5 ⁇ 10 ⁇ 4 atm.
- the GaN thick film 18 is by itself separated and a GaN self-standing substrate 19 with a diameter of 3 inches is obtained ( FIG. 2E ).
- the thickness distribution of the GaN substrate 19 is well uniform as 800 ⁇ 10 ⁇ m.
- a void-formed substrate ( FIG. 2B ) with a diameter of 4.5 inches is fabricated.
- the substrate is placed in the HVPE furnace while being held down on the susceptor by using a ring-shaped jig to remedy the warping.
- GaN is grown thereon like the inventive example 1 and, after the self-separation in the cooling process, a GaN substrate with a diameter of 4 inches is obtained.
- the GaN substrate obtained has high and uniform properties like the inventive example 1.
- the GaN substrate obtained in the inventive example 3 is used as a seed crystal to grow a 40 mm long GaN ingot. Although the diameter is slightly increased in the process of growth, a transparent single crystal ingot with no crack can be obtained by grinding into a circular column with a diameter of 4 inches.
- the position of (1-100) face is determined by X-ray diffraction, and a 15 mm long orientation flat is thereby formed.
- a 10 mm long second orientation flat is formed at a position rotated by 90 degrees. Then, it is sliced by a wire saw to have 40 GaN substrates with a thickness of 500 ⁇ m.
- Each of the substrates is mirror-polished at both faces thereof to get a transparent GaN single crystal substrate with a diameter of 4 inches.
- a GaN substrate with a diameter of 3 inches is provided Then, a 40 mm long GaN ingot is grown thereon like the inventive example 5.
- the diameter is slightly increased in the process of growth, a transparent single crystal ingot can be obtained by grinding into a circular column with a diameter of 3 inches.
- a number of fine cracks are generated at a growth portion longer than 20 mm. This may be caused by that the crystal orientation distribution of the seed substrate is large and a large compression stress is applied during growth.
- the position of (1-100) face is determined by X-ray diffraction, and a 15 mm long orientation flat is thereby formed.
- a 10 mm long second orientation flat is formed at a position rotated by 90 degrees. Then, it is sliced by a wire saw to have 20 GaN substrates with a thickness of 500 ⁇ m.
- Each of the substrates is mirror-polished at both faces thereof to get a transparent GaN single crystal substrate with a diameter of 3 inches.
- a blue LED epitaxial wafer is fabricated by MOVPE. The wafer is diced out into a number of LED's. Its active layer is formed in multiquantum well structure of InGaN/AlGaN and is sandwiched by AlGaN cladding layers.
- the emission wavelength of the obtained LED's has a sufficient uniformity as 405 ⁇ 3 nm.
- 90% or more of the entire area of the epitaxial wafer meet the standard. This is because the crystal orientation of the GaN substrate used is uniform and, therefore, the composition of InGaN in the active layer is kept uniform in plane.
- the invention is applied to a method of making a GaN substrate
- the invention can be also applied to a method of making a self-standing substrate of a ternary single crystal such as aluminum gallium nitride (AlGaN) and gallium indium nitride (GaInN) or a method of making a p-type GaN substrate doped with Mg etc.
- AlGaN aluminum gallium nitride
- GaInN gallium indium nitride
- the invention can be applied not only to a manufacture of a self-standing substrate but also to a manufacture of a substrate with a hetero-substrate such as sapphire.
- the group III nitride-based compound semiconductor substrate obtained by the invention can be widely used as a substrate for GaN-based devices. Especially, when it is used as a substrate for a laser diode, the laser diode can have a high performance and a high reliability since a good GaN-based crystal can be formed thereon with a reduced crystal defect.
Abstract
A method of making a group III-V nitride-based semiconductor substrate has the steps of: providing a first crystal substrate; placing the first crystal substrate on a susceptor; holding down the first crystal substrate on the susceptor; and growing a first group III-V nitride-based semiconductor crystal on the first crystal substrate.
Description
- The present application is based on Japanese patent application No. 2005-113416, the entire contents of which are incorporated herein by reference.
- 1. Field of the Invention
- This invention relates to a group III-V nitride-based semiconductor substrate and a method of making the same.
- 2. Description of the Related Art
- GaN-based compound semiconductors such as gallium nitride (GaN), indium gallium nitride (InGaN) and aluminum gallium nitride (AlGaN) attract attention for a material of blue light emitting diode (LED) or laser diode (LD). Further, since the GaN-based compound semiconductors have a good heat resistance and environment resistance, they have begun to be applied to other electronic devices.
- At present, a substrate used widely to grow GaN is sapphire. In general, a method is used in which GaN is epitaxially grown on a sapphire single crystal substrate by MOVPE (metalorganic vapor phase epitaxy) etc.
- However, since the sapphire substrate mismatches in lattice constant with the GaN, a GaN single crystal cannot be grown directly on the sapphire substrate. Therefore, a method is disclosed in which a buffer layer (=low-temperature growth buffer layer) of AlN or GaN is grown on the sapphire substrate at a low temperature to buffer strain in lattice and then GaN is grown thereon (e g., Japanese patent Nos. 3026087 and 2751963 and Japanese patent publication No. 8-8217).
- By using the low-temperature growth buffer layer, the epitaxial growth of GaN single crystal can be realized. However, the above method still has a problem that the grown GaN has a number of defects since the lattice mismatch between the substrate and the GaN is not eliminated. It is presumed that the defect brings some failure to a manufacture of GaN-based LD.
- Under the circumstances, it is desired to develop a GaN self-standing substrate. Since it is difficult to grow a large ingot of GaN from melt unlike Si or GaAs, various methods such as the ultrahigh temperature and pressure method, flux method and HVPE (hydride vapor phase epitaxy) have been tried to make the GaN self-standing substrate.
- A typical method for making a nitride semiconductor self-standing substrate is conducted such that a GaN thick film is grown on a hetero-substrate such as sapphire by HVPE and then the hetero-substrate is removed to obtain a GaN self-standing substrate (e.g., JP-A-2003-178984, herein referred to as VAS method and the entire contents of JP-A-2003-178984 are incorporated herein by reference). In this method, a void-containing layer functions as a strain buffering layer so as to buffer a strain caused by a difference in lattice constant or thermal expansion coefficient between the underlying substrate and the group III nitride semiconductor layer grown thereon. By the method, a substrate of group III nitride semiconductor can be obtained which offers a reduced defect density and a good crystalline quality without warping. Further, the self-standing substrate thus obtained can be easily separated. Based on the method, GaN substrates with a reduced dislocation have begun to be commercially available.
- However, a large practical GaN single crystal with a high crystalline quality has never been developed even in the above methods.
- In the ultrahigh temperature and pressure method, which needs tens of thousands of atmospheres and thousands of degrees, it is difficult to grow a large crystal. Therefore, it only can provide a GaN crystal with a diameter of several millimeters and a thickness of several tens of millimeters.
- In the flux method, although it only needs hundreds of atmospheres and about a thousand degrees, it only can provide a GaN crystal with a diameter of several millimeters and a thickness of several tens of micrometers. In addition, there are problems that removal of nitrogen occurs and Na or Ca flux is diffused into the crystal. Furthermore, since it is difficult to control the generation of crystal nuclei at initial growth, polycrystal may be contained.
- In the HVPE method, a crystal with a diameter of about 5.08 cm (=2 inches) has been developed. However, in view of economical aspect of device fabrication, a lager wafer of GaN single crystal is desired with a diameter of 7.62 cm (=3 inches) or more. In fabricating such a large wafer, there is a problem that in-plane properties thereof become significantly non-uniform and thereby the large area becomes meaningless. For example, the non-uniformity of dislocation density may cause dispersion in reliability of each device. The non-uniformity of electrical resistivity (carrier concentration) may cause dispersion in operating voltage. The non-uniformity of crystal orientation may cause dispersion in emission wavelength since the InGaN composition of an active layer may be non-uniform. The non-uniformity of thickness, especially unevenness on the back surface face of the substrate causes non-uniformity of temperature distribution during growth of device epitaxial layer. This affects the InGaN composition of the active layer to cause non-uniformity in the emission wavelength.
- It is an object of the invention to provide a group III-V nitride-based semiconductor substrate and a method of the same that can offer an improved uniformity in in-plane property.
- (1) According to one aspect of the invention, a group III-V nitride-based semiconductor substrate comprises;
- a group III-V nitride-based semiconductor crystal;
- wherein said substrate has a surface area of 45 cm2 or more,
- said substrate has thickness of 200 μm or more,
- said substrate has an in-plane dislocation density of 2×107 cm−2 or less in average, and
- the in-plane dislocation density is 150% or less of the average at maximum.
- (i) It is preferred that said substrate has at a surface thereof a dispersion in crystal axis of ±0.3 degrees or less,
- (ii) It is preferred that said substrate has at an arbitrary point of a surface thereof a carrier concentration that falls within ±20% of an average carrier concentration at the surface.
- (iii) It is preferred that said substrate has at an arbitrary point of a surface thereof a thickness that falls within ±10 μm from an average thickness at the surface
- (iv) It is preferred that said group III-V nitride-based semiconductor crystal has an FWHM value of X-ray rocking curve of 250 seconds or less.
- (v) It is preferred that said group III-V nitride-based semiconductor crystal has a composition of InxAlyGa1-x-yN (x≧0, y≧0, x+y≦1).
- (2) According to another aspect of the invention, a method of making a group III-V nitride-based semiconductor substrate comprises:
- providing a first crystal substrate;
- placing the first crystal substrate on a susceptor;
- holding down the first crystal substrate on the susceptor; and
- growing a first group III-V nitride-based semiconductor crystal on the first crystal substrate.
- (vi) It is preferred that the first crystal substrate is bonded to the susceptor.
- (vii) It is preferred that the first crystal substrate is a hetero-substrate that has a composition different from the first group III-V nitride-based semiconductor crystal.
- (viii) It is preferred that the first crystal substrate is a hetero-substrate that has a composition different from the first group III-V nitride-based semiconductor crystal, and
- said method further comprising:
- growing a second group III-V nitride-based semiconductor crystal on the hetero-substrate,
- providing the second group III-V nitride-based semiconductor crystal with a void;
- growing a third group III-V nitride-based semiconductor crystal on the second group III-V nitride-based semiconductor crystal provided with the void;
- removing the hetero-substrate and the second group III-V nitride-based semiconductor crystal to have the third group III-V nitride-based semiconductor crystal that corresponds to the first group III-V nitride-based semiconductor crystal.
- (ix) It is preferred that said hetero-substrate is a sapphire substrate.
- (x) It is preferred that the first crystal substrate is a seed crystal substrate that has the same composition as the first group III-V nitride-based semiconductor crystal.
- (xi) It is preferred that said first group III-V nitride-based semiconductor crystal has a composition of InxAlyGa1-x-yN (x≧0, y≧0, x+y≦1).
- (3) According to another aspect of the invention, a method of making a group III-V nitride-based semiconductor substrate comprises:
- providing a first crystal substrate;
- placing the first crystal substrate on a susceptor;
- holding down the first crystal substrate on the susceptor to allow exposition of a part of an opposite surface of the first crystal substrate to a surface of the first crystal substrate that faces the susceptor; and
- growing a first group III-V nitride-based semiconductor crystal on the exposed opposite surface of the first crystal substrate.
- (xii) It is preferred that the first crystal substrate is bonded to the susceptor.
- (xiii) It is preferred that the first crystal substrate is a hetero-substrate that has a composition different from the first group III-V nitride-based semiconductor crystal.
- (xiv) It is preferred that the first crystal substrate is a hetero-substrate that has a composition different from the first group III-V nitride-based semiconductor crystal, and
- said method further comprising
- growing a second group III-V nitride-based semiconductor crystal on the hetero-substrate,
- providing the second group III-V nitride-based semiconductor crystal with a void;
- growing a third group III-V nitride-based semiconductor crystal on the second group III-V nitride-based semiconductor crystal provided with the void;
- removing the hetero-substrate and the second group III-V nitride-based semiconductor crystal to have the third group III-V nitride-based semiconductor crystal that corresponds to the first group III-V nitride-based semiconductor crystal.
- (xv) It is preferred that said hetero-substrate is a sapphire substrate.
- (xvi) It is preferred that the first crystal substrate is a seed crystal substrate that has the same composition as the first group III-V nitride-based semiconductor crystal.
- (xvii) It is preferred that said first group III-V nitride-based semiconductor crystal has a composition of InxAlyGa1-x-yN (x≧0, y≧0, x+y≦1).
- The invention is featured in that, in the growth of nitride semiconductor by HVPE (hydride vapor phase epitaxy), temperature of crystal during the growth is kept uniform to make the growth speed and impurity concentration uniform. Thereby, various properties such as dislocation density to be varied therewith can be significantly enhanced.
- As the result of many researches, it is found by the inventor that the in-plane non-uniformity described earlier is basically caused by non-uniformity in growth temperature.
- First, the non-uniformity in growth temperature causes non-uniformity in growth speed. The hetero-epitaxial growth of GaN proceeds generally in the Volmer-Weber type growth manner, wherein a number of growth initial nuclei are generated, they are bonded to each other as the growth progresses, and it is finally transited into two-dimensional growth. If the growth speed is varied, a nucleus generation density at initial growth and the subsequent planarization behavior are varied and, thereby, a dislocation density at final surface is varied. Furthermore, if the growth speed is varied, a dopant introduction density is also varied, which causes non-uniformity in carrier concentration and electrical resistivity. In addition, although a GaN crystal after growth is generally polished at both faces thereof to be used for a wafer, the in-plane polishing speed may be non-uniform due to a difference in dislocation density or carrier concentration and, thereby, the final thickness may be non-uniform.
- Second, the non-uniformity in growth temperature causes a warp in crystal. Thereby, the in-plane dispersion of crystal axes may be increased.
- Accordingly, it is important to keep the growth temperature uniform so as to have a uniform property in large-diameter substrate. In general, the crystal growth of GaN is conducted placing a seed substrate on a black-body susceptor of graphite or SiC. Since the GaN or sapphire has a transparent body, the heating of substrate is conducted mainly by thermal conduction through the susceptor. Thus, it is important to keep the substrate uniformly in contact with the susceptor.
- As described above, it is very necessary that a flat substrate is placed on a flat susceptor to secure a sufficient thermal contact therebetween. However, it is found by the inventor that, in hetero-epitaxial growth of a thick film as thick as several hundreds of micrometers, different from general homo-epitaxial growth or hetero-epitamial growth of a thin film, the substrate is significantly warped during growth and the thermal contact therebetween may be therefore non-uniform. Namely, the growth of GaN on a hetero-epitaxial substrate such as sapphire, as described earlier, proceeds generally in the Volmer-Weber type growth manner, where the initial growth nucleus attract each other so as to minimize the surface energy when being combined each together and, as a result, a tensile stress must be generated. It does not matter when the thickness of the growth film is sufficiently thin as compared to the thickness of the underlying substrate. However, when the thickness of the growth film is equal to or greater than the underlying substrate, a large warping is generated such that it can seriously affect the thermal distribution of the in-plane growth substrate.
- Solutions to these problems made by the inventor are as follows.
- (a) The underlying substrate is to be bonded to the susceptor. For example, alumina-based high-temperature adhesives can be used such that a sufficient adhesion force is applied therebetween even at a high temperature of higher than 100° C.
- (b) The underlying substrate is to be mechanically held down on the susceptor For example, a ring-shaped jig can be used such that the underlying substrate is secured to the susceptor through a screw so as to grow a crystal in an opening region except the jig.
- (C) The underlying substrate is to have an increased thickness. Thereby, its rigidity can be enhanced to prevent the deformation by a stress.
- (d) An opaque body is to be disposed under the underlying substrate For example, a carbon thin layer is coated on the bottom face of the underlying substrate. Thereby, even when the underlying substrate locally gets away from the susceptor, the reduction of temperature can be prevented at that portion
- By suitably combining any of the above solutions, the following large-size substrate can be obtained with a high uniformity In detail, a group III-V nitride semiconductor substrate with a diameter of 7.62 cm (=3 inches) (or with an equivalent surface area of 45 cm2) and with a thickness of 200 μm or more to allow a sufficient rigidity to prevent the breaking in the handling process, wherein:
- (A) its dislocation density is 2×107 cm−2 or less in average and its maximum value is 150% or less of the average value;
- (B) its in-plane dispersion of c-axis (i.e., an angle defined by a main plane and c-axis) is ±3.0 degrees or less;
- (C) its in-plane dispersion of electrical resistivity (i.e., carrier concentration) is ±20% or less of an average value; and
- (D) its in-plane dispersion of thickness is ±10 μm or less of an average value.
- Using a substrate of the invention, a device epitaxial layer with a large surface area can be fabricated in a high uniformity. Therefore, it is very advantageous in economical aspect. Thus, in the invention, the in-plane non-uniformity of the substrate properties caused by the non-uniformity of the growth temperature can be eliminated. Thereby, a group III-V nitride semiconductor substrate can be obtained with a high quality and a high uniformity.
- The preferred embodiments according to the invention will be explained below referring to the drawing, wherein:
-
FIGS. 1A to 1E are illustrative cross sectional views showing of a method of making a group III-V nitride semiconductor substrate in a first preferred embodiment according to the invention; -
FIGS. 2A to 2E are illustrative cross sectional views showing of a method of making a group III-V nitride semiconductor substrate in a second preferred embodiment according to the invention; and -
FIGS. 3A to 3E are illustrative cross sectional views showing a conventional method of making a group III-V nitride semiconductor substrate, - For the sake of comparison, a conventional example will be first explained below referring to
FIGS. 3A to 3E. - As shown in
FIGS. 3A and 3B , a 300 nm thick GaNunderlying layer 2 is formed on a c-face sapphire substrate with a diameter of 7.62 cm (=3 inches) and a thickness of 330 μm by MOVPE - Then, it is placed in a HVPE furnace and a Si-doped GaN
thick film 3 is grown (FIG. 3C ). Carrier gas is N2:H2=9:1. Partial pressures are GaCl=9×10−3 atm, NH3=5×10−2 atm. For n-type doping, SiH2Cl2 gas is flown at partial pressure of 5×10−4 atm. Growth temperature is 1070° C. - The resultant GaN crystal (i.e., GaN thick film 3) has a thickness of 800 μm at the central portion and 500 μm at the outermost portion. Thus, it has a significant distribution in thickness.
- By irradiating YAG laser from the backside of the
sapphire substrate 1, aGaN substrate 4 is separated decomposing a GaN crystal at the interface (FIG. 3D ). TheGaN substrate 4 separated is warped in the form of a concave, whose curvature radius is about 3 meters. By polishing both faces of theGaN substrate 4, a 3-inch GaN self-standingsubstrate 5 with a thickness of 430 μm at the central portion is obtained (FIG. 3E ). However, it has a highly reduced thickness of 400 μm at the outermost portion. - In evaluating the uniformity of the properties of the GaN substrate (i.e., GaN self-standing substrate 5), it is found that there is a significant in-plane distribution. Namely, the dislocation density is 2×107 cm−2 at the outermost portion while it is 1×107 cm−2 at the central portion. The carrier concentration is 3×1018 cm−3 at the outermost portion while it is 1×1018 cm−3 at the central portion. It is presumed that these distributions are caused by that the in-plane distribution of growth speed is large. That the polishing rate is faster at the outer portion of the substrate and the thickness of the outer portion is thus reduced may be affected by the non-uniformity of the dislocation density and the carrier concentration. Further, the c-axis is inclined as much as about ±0.7 to the center of the substrate. This inclination may be generated because of directly polishing the warped substrate.
- Next, by using the GaN self-standing
substrate 5, a blue LED is epitaxially grown by MOVPE. Its active layer is formed in multiauantum well structure of InGaN/AlGaN and is sandwiched by AlGaN cladding layers. The emission wavelength of the obtained LED is highly dispersed as 405±15 nm, and 90% of the entire area of the epitaxial wafer does not meet the standard. This is because the crystal orientation of the GaN substrate used is not uniform and, therefore, the composition of InGaN in the active layer is dispersed in plane. In the accelerated test of device life, about 10% of samples have a life less than 10000 hours in high output operation at 1 W. This may be caused by a local region with a high dislocation density. -
FIGS. 1A to 1E are illustrative cross sectional views showing of a method of making a group III-V nitride semiconductor substrate in the first preferred embodiment according to the invention. - As shown in
FIGS. 1A and 1B , a 300 nm thick GaNunderlying layer 7 is formed on a c-face sapphire substrate 6 with a diameter of 7.62 cm (=3 inches) and a thickness of 650 μm by MOVPE. - Then, like the conventional example, it is placed in a HVPE furnace and a Si-doped GaN thick film 8 is grown (
FIG. 1C ). Carrier gas is N2:H2=1:1. Partial pressures are GaCl=9×10−3 atm, NH3=1×10−1 atm. For n-type doping, SiH2Cl2 gas is flown at partial pressure of 5×10−4 atm. Growth temperature is 1070° C. - By irradiating YAG laser from the backside of the
sapphire substrate 6, aGaN substrate 9 is separated decomposing a GaN crystal at the interface (FIG. 1D ). - The resultant GaN crystal (i.e., GaN thick film 8) has a thickness of 800 μm at the central portion and 700 μm at the outermost portion. Thus, it has an improved distribution in thickness. The
GaN substrate 9 separated has a curvature radius of about 10 meters, where the warping is significantly improved. This is because of using thethick sapphire substrate 6. The improvement of thickness distribution maybe caused such that the warping during growth is reduced, the uniform contact with the susceptor (not shown) is thereby obtained and the growth temperature becomes uniform in plane. - Both faces of the
GaN substrate 9 are polished (FIG. 1E ) Because of the improved thickness distribution and warping, though it has a reduced growth thickness, by polishing both faces of the substrate, a 3-inch GaN self-standingsubstrate 10 with a uniform thickness of 430 μm can be obtained. - In evaluating the uniformity of the properties of the GaN substrate (i.e., GaN self-standing substrate 10), it is found that there is a significant improvement. The dislocation density is 1.4×107 cm−2 at the outermost portion while it is 1×107 cm−2 at the central portion. The carrier concentration is 1.3×1018 cm−3 at the outermost portion while it is 1×1018 cm−3 at the central portion. Further, the c-axis is inclined about ±0.21.
- In the inventive example 1, an about 1 μm thick carbon layer is formed on the back face of the
sapphire substrate 6 and then the HVPE growth is conducted in like manner. Thereby, the temperature distribution during growth can be further improved The thickness distribution as grown is 800 μm at the central portion and 750 μm at the outermost portion, - The properties of the GaN substrate are also improved. The dislocation density is 1×107 cm−2 both at the central portion and at the outermost portion The carrier concentration is 1×1018 cm−3 both at the central portion and at the outermost portion. Further, the c-axis is inclined about ±0.18.
-
FIGS. 2A to 2E are illustrative cross sectional views showing of a method of making a group III-V nitride semiconductor substrate in the third preferred embodiment according to the invention. - As shown in
FIG. 2A , a c-face sapphire substrate 6 with a diameter of 7.62 cm (=3 inches) and a thickness of 330 μm is provided. - Then, a 300 nm thick GaN thin film (=GaN under lying layer 17) is formed on the
sapphire substrate 6. Then, a 20 nm thick Ti layer is formed thereon in vacuum deposition. Then, it is thermally treated in carrier gas of H2:NH3=4:1 at 1060° C. for 30 min. Thereby, the Ti layer is nitrided into a TiN layer and formed into mesh-like structure (i.e., TiN nano-mask 11) with a number of fine holes of tens of nanometers. On the other hand, the GaNunderlying layer 17 is etched to have therein voids reaching up to the sapphire substrate 6 (FIG. 2B ). - Then, the void-formed substrate is placed in the HVPE furnace while being bonded through an alumina-based high-
temperature adhesive 12 to the graphite susceptor (not shown) (FIG. 2C ). - Then, a 800 μm thick GaN
thick film 18 is grown thereon by HVPE (FIG. 2D ). Source gases for growth are NH3 and GaCl, and partial pressures are GaCl=8×10−3 atm, NH3=8×10−2 atm. The growth pressure and temperature are atmospheric pressure and 1040° C. For n-type doping, SiH2Cl2 gas is flown at partial pressure of 5×10−4 atm. - In a cooling process after completing the growth, the GaN
thick film 18 is by itself separated and a GaN self-standingsubstrate 19 with a diameter of 3 inches is obtained (FIG. 2E ). The thickness distribution of theGaN substrate 19 is well uniform as 800±10 μm. - In measuring the dislocation density of the
GaN substrate 19 by cathode luminescence, a very small value is measured 1×106 cm−2 in average. The dispersion (in-plane distribution) is also well uniform as 1±0.2×106 cm−2. The FWHM value of X-ray rocking curve is 40 sec. for (0002) reflection. This evidences the low dislocation density. Further, the dispersion of crystal axes (c-axes) is ±0.1 degrees and the dispersion of carrier concentrations is (3.0±0.2)×1018 cm−3. Thus, it is found that all the main properties are well uniform. - Like the inventive example 3, a void-formed substrate (
FIG. 2B ) with a diameter of 4.5 inches is fabricated. The substrate is placed in the HVPE furnace while being held down on the susceptor by using a ring-shaped jig to remedy the warping. Then, GaN is grown thereon like the inventive example 1 and, after the self-separation in the cooling process, a GaN substrate with a diameter of 4 inches is obtained. The GaN substrate obtained has high and uniform properties like the inventive example 1. - The GaN substrate obtained in the inventive example 3 is used as a seed crystal to grow a 40 mm long GaN ingot. Although the diameter is slightly increased in the process of growth, a transparent single crystal ingot with no crack can be obtained by grinding into a circular column with a diameter of 4 inches.
- The position of (1-100) face is determined by X-ray diffraction, and a 15 mm long orientation flat is thereby formed. In order to identify a side of the substrate after slicing, a 10 mm long second orientation flat is formed at a position rotated by 90 degrees. Then, it is sliced by a wire saw to have 40 GaN substrates with a thickness of 500 μm. Each of the substrates is mirror-polished at both faces thereof to get a transparent GaN single crystal substrate with a diameter of 4 inches.
- In measuring the dislocation density of the GaN substrate by cathode luminescence, a very small value is measured 5×105 cm−2 in average. The dispersion (in-plane distribution) is also well uniform as 5±0.2×105 cm−2. The FWHM value of X-ray rocking curve is 30 sec. for (0002) reflection. This evidences the low dislocation density, Further, the dispersion of crystal axes (c-axes) is ±0.01 degrees and the dispersion of carrier concentrations is (3.0±0.2)×1018 cm−3. Thus, it is found that all the main properties are well uniform.
- Like the conventional example, a GaN substrate with a diameter of 3 inches is provided Then, a 40 mm long GaN ingot is grown thereon like the inventive example 5. Although the diameter is slightly increased in the process of growth, a transparent single crystal ingot can be obtained by grinding into a circular column with a diameter of 3 inches. However, it is found that a number of fine cracks are generated at a growth portion longer than 20 mm. This may be caused by that the crystal orientation distribution of the seed substrate is large and a large compression stress is applied during growth.
- The position of (1-100) face is determined by X-ray diffraction, and a 15 mm long orientation flat is thereby formed. In order to identify a side of the substrate after slicing, a 10 mm long second orientation flat is formed at a position rotated by 90 degrees. Then, it is sliced by a wire saw to have 20 GaN substrates with a thickness of 500 μm. Each of the substrates is mirror-polished at both faces thereof to get a transparent GaN single crystal substrate with a diameter of 3 inches.
- In measuring the dislocation density of the GaN substrate by cathode luminescence, a good value is measured 1×106 cm−2 in average. However, an insufficient value is also measured about 1×107 cm−2 depending on the in-plane position. Further, the dispersion of crystal axes (coaxes) is as large as ±0.4 degrees.
- By using a GaN substrate obtained in the inventive example 5, a blue LED epitaxial wafer is fabricated by MOVPE. The wafer is diced out into a number of LED's. Its active layer is formed in multiquantum well structure of InGaN/AlGaN and is sandwiched by AlGaN cladding layers.
- The emission wavelength of the obtained LED's has a sufficient uniformity as 405±3 nm. Thus, 90% or more of the entire area of the epitaxial wafer meet the standard. This is because the crystal orientation of the GaN substrate used is uniform and, therefore, the composition of InGaN in the active layer is kept uniform in plane.
- In the accelerated test of device life, all samples have a life more than 100,000 hours in high output operation at 1 W.
- Although in the above embodiments the invention is applied to a method of making a GaN substrate, the invention can be also applied to a method of making a self-standing substrate of a ternary single crystal such as aluminum gallium nitride (AlGaN) and gallium indium nitride (GaInN) or a method of making a p-type GaN substrate doped with Mg etc.
- Further, the invention can be applied not only to a manufacture of a self-standing substrate but also to a manufacture of a substrate with a hetero-substrate such as sapphire.
- The group III nitride-based compound semiconductor substrate obtained by the invention can be widely used as a substrate for GaN-based devices. Especially, when it is used as a substrate for a laser diode, the laser diode can have a high performance and a high reliability since a good GaN-based crystal can be formed thereon with a reduced crystal defect.
- Although the invention has been described with respect to the specific embodiments for complete and clear disclosure, the appended claims are not to be thus limited but are to be construed as embodying all modifications and alternative constructions that may occur to one skilled in the art which fairly fall within the basic teaching herein set forth.
Claims (20)
1. A group III-V nitride-based semiconductor substrate, comprising:
a group III-V nitride-based semiconductor crystal;
wherein said substrate has a surface area of 45 cm2 or more,
said substrate has thickness of 200 μm or more,
said substrate has an in-plane dislocation density of 2×107 cm−2 or less in average, and
the in-plane dislocation density is 150% or less of the average at maximum.
2. The group III-V nitride-based semiconductor substrate according to claim 1 , wherein:
said substrate has at a surface thereof a dispersion in crystal axis of ±0.3 degrees or less.
3. The group III-V nitride-based semiconductor substrate according to claim 1 , wherein:
said substrate has at an arbitrary point of a surface thereof a carrier concentration that falls within ±20% of an average carrier concentration at the surface.
4. The group III-V nitride-based semiconductor substrate according to claim 1 , wherein:
said substrate has at an arbitrary point of a surface thereof a thickness that falls within ±10 μm from an average thickness at the surface.
5. The group III-V nitride-based semiconductor substrate according to claim 1 , wherein;
said group III-V nitride-based semiconductor crystal has an FWHM value of X-ray rocking curve of 250 seconds or less.
6. The group III-V nitride-based semiconductor substrate according to claim 1 , wherein:
said group III-V nitride-based semiconductor crystal has a composition of InxAlyGa1-x-yN (x≧0, y≧0, x+y≦1)
7. A method of making a group III-V nitride-based semiconductor substrate, comprising:
providing a first crystal substrate;
placing the first crystal substrate on a susceptor;
holding down the first crystal substrate on the susceptor; and
growing a first group III-V nitride-based semiconductor crystal on the first crystal substrate.
8. The method according to claim 7 , wherein:
the first crystal substrate is bonded to the susceptor.
9. The method according to claim 7 , wherein:
the first crystal substrate is a hetero-substrate that has a composition different from the first group III-V nitride-based semiconductor crystal.
10. The method according to claim 7 , wherein
the first crystal substrate is a hetero-substrate that has a composition different from the first group III-V nitride-based semiconductor crystal, and
said method further comprising;
growing a second group III-V nitride-based semiconductor crystal on the hetero-substrate,
providing the second group III-V nitride-based semiconductor crystal with a void;
growing a third group III-V nitride-based semiconductor crystal on the second group III-V nitride-based semiconductor crystal provided with the void;
removing the hetero-substrate and the second group III-V nitride-based semiconductor crystal to have the third group III-V nitride-based semiconductor crystal that corresponds to the first group III-V nitride-based semiconductor crystal.
11. The method according to claim 9 , wherein:
said hetero-substrate is a sapphire substrate.
12. The method according to claim 7 , wherein:
the first crystal substrate is a seed crystal substrate that has the same composition as the first group III-V nitride-based semiconductor crystal.
13. The method according to claim 7 , wherein:
said first group III-V nitride-based semiconductor crystal has a composition of InxAlyGa1-x-yN (x≧0, y≧0, x+y≦1).
14. A method of making a group III-V nitride-based semiconductor substrate, comprising;
providing a first crystal substrate;
placing the first crystal substrate on a susceptor;
holding down the first crystal substrate on the susceptor to allow exposition of a part of an opposite surface of the first crystal substrate to a surface of the first crystal substrate that faces the susceptor; and
growing a first group III-V nitride-based semiconductor crystal on the exposed opposite surface of the first crystal substrate.
15. The method according to claim 14 , wherein:
the first crystal substrate is bonded to the susceptor.
16. The method according to claim 14 , wherein:
the first crystal substrate is a hetero-substrate that has a composition different from the first group III-V nitride-based semiconductor crystal.
17. The method according to claim 14 , wherein:
the first crystal substrate is a hetero-substrate that has a composition different from the first group III-V nitride-based semiconductor crystal, and
said method further comprising:
growing a second group III-V nitride-based semiconductor crystal on the hetero-substrate,
providing the second group III-V nitride-based semiconductor crystal with a void;
growing a third group III-V nitride-based semiconductor crystal on the second group III-V nitride-based semiconductor crystal provided with the void;
removing the hetero-substrate and the second group III-V nitride-based semiconductor crystal to have the third group III-V nitride-based semiconductor crystal that corresponds to the first group III-V nitride-based semiconductor crystal.
18. The method according to claim 16 , wherein:
said hetero-substrate is a sapphire substrate.
19. The method according to claim 14 , wherein:
the first crystal substrate is a seed crystal substrate that has the same composition as the first group III-V nitride-based semiconductor crystal.
20. The method according to claim 14 , wherein:
said first group III-V nitride-based semiconductor crystal has a composition of InxAlyGa1-x-yN (x≧0, y≧0, x+y≦1).
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US12/662,461 US8143702B2 (en) | 2005-04-11 | 2010-04-19 | Group III-V nitride based semiconductor substrate and method of making same |
Applications Claiming Priority (2)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP2005-113416 | 2005-04-11 | ||
JP2005113416A JP4849296B2 (en) | 2005-04-11 | 2005-04-11 | GaN substrate |
Related Child Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
US12/662,461 Continuation US8143702B2 (en) | 2005-04-11 | 2010-04-19 | Group III-V nitride based semiconductor substrate and method of making same |
Publications (1)
Publication Number | Publication Date |
---|---|
US20060226414A1 true US20060226414A1 (en) | 2006-10-12 |
Family
ID=37082360
Family Applications (2)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
US11/176,687 Abandoned US20060226414A1 (en) | 2005-04-11 | 2005-07-08 | Group III-V nitride-based semiconductor substrate and method of making same |
US12/662,461 Active US8143702B2 (en) | 2005-04-11 | 2010-04-19 | Group III-V nitride based semiconductor substrate and method of making same |
Family Applications After (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
US12/662,461 Active US8143702B2 (en) | 2005-04-11 | 2010-04-19 | Group III-V nitride based semiconductor substrate and method of making same |
Country Status (2)
Country | Link |
---|---|
US (2) | US20060226414A1 (en) |
JP (1) | JP4849296B2 (en) |
Cited By (23)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US20080272377A1 (en) * | 2007-05-02 | 2008-11-06 | Sumitomo Electric Industries, Ltd. | Gallium Nitride Substrate and Gallium Nitride Film Deposition Method |
US20080303033A1 (en) * | 2007-06-05 | 2008-12-11 | Cree, Inc. | Formation of nitride-based optoelectronic and electronic device structures on lattice-matched substrates |
US20090045072A1 (en) * | 2005-09-06 | 2009-02-19 | Japan Science And Technology Agency | Iii/v group nitride semiconductor, photocatalytic semiconductor device, photocatalytic oxidation-reduction reaction apparatus and execution process of photoelectrochemical reaction |
US20090127662A1 (en) * | 2007-11-20 | 2009-05-21 | Sumitomo Electric Industries, Ltd. | Group iii nitride semiconductor crystal substrate and semiconductor device |
US20090127663A1 (en) * | 2007-11-20 | 2009-05-21 | Sumitomo Electric Industries. Ltd. | Group iii nitride semiconductor crystal growing method, group iii nitride semiconductor crystal substrate fabrication method, and group iii nitride semiconductor crystal substrate |
US20100258812A1 (en) * | 2009-04-13 | 2010-10-14 | Hitachi Cable, Ltd. | Group-iii nitride semiconductor freestanding substrate and manufacturing method of the same |
US20100272141A1 (en) * | 2009-04-23 | 2010-10-28 | Hitachi Cable, Ltd. | Nitride semiconductor freestanding substrate and manufacturing method of the same, and laser diode |
US20110147759A1 (en) * | 2009-12-18 | 2011-06-23 | Hitachi Cable, Ltd. | Group iii nitride semiconductor substrate and manufacturing method of the same |
US20120018732A1 (en) * | 2009-01-15 | 2012-01-26 | Disco Corporation | Inside reforming substrate for epitaxial growth; crystal film forming element, device, and bulk substrate produced using the same; and method for producing the same |
US8143702B2 (en) | 2005-04-11 | 2012-03-27 | Hitachi Cable, Ltd. | Group III-V nitride based semiconductor substrate and method of making same |
US20140061660A1 (en) * | 2012-08-30 | 2014-03-06 | Kabushiki Kaisha Toshiba | Semiconductor light emitting device and manufacturing method thereof |
CN104115258A (en) * | 2012-02-20 | 2014-10-22 | 三垦电气株式会社 | Epitaxial substrate, semiconductor device, and method for manufacturing semiconductor device |
US20140319533A1 (en) * | 2008-08-04 | 2014-10-30 | Goldeneye, Inc. | Flexible semiconductor devices based on flexible freestanding epitaxial elements |
CN105026625A (en) * | 2013-02-08 | 2015-11-04 | 并木精密宝石株式会社 | GaN substrate and method for manufacturing GaN substrate |
US10060047B2 (en) | 2011-09-12 | 2018-08-28 | Sumitomo Chemical Company, Limited | Nitride semiconductor crystal producing method including growing nitride semiconductor crystal over seed crystal substrate |
US10260165B2 (en) | 2016-01-05 | 2019-04-16 | Osaka University | Method for manufacturing nitride crystal substrate and substrate for crystal growth |
US10364510B2 (en) | 2015-11-25 | 2019-07-30 | Sciocs Company Limited | Substrate for crystal growth having a plurality of group III nitride seed crystals arranged in a disc shape |
CN110499533A (en) * | 2018-05-16 | 2019-11-26 | 赛奥科思有限公司 | The manufacturing method of element nitride crystal substrate and element nitride crystal substrate |
US10584031B2 (en) | 2016-03-08 | 2020-03-10 | Sciocs Company Limited | Nitride crystal substrate |
CN111356794A (en) * | 2018-02-23 | 2020-06-30 | 住友电气工业株式会社 | Gallium nitride crystal substrate |
CN112151355A (en) * | 2019-06-28 | 2020-12-29 | 东莞市中镓半导体科技有限公司 | Method for manufacturing gallium nitride self-supporting substrate |
US11810782B2 (en) | 2016-08-08 | 2023-11-07 | Mitsubishi Chemical Corporation | Conductive C-plane GaN substrate |
US11908688B2 (en) | 2018-08-29 | 2024-02-20 | Sumitomo Chemical Company, Limited | Method for manufacturing nitride semiconductor substrate, nitride semiconductor substrate and layered structure |
Families Citing this family (33)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US9518340B2 (en) | 2006-04-07 | 2016-12-13 | Sixpoint Materials, Inc. | Method of growing group III nitride crystals |
JP2008297191A (en) * | 2007-05-02 | 2008-12-11 | Sumitomo Electric Ind Ltd | Gallium nitride substrate and gallium nitride film deposition method |
JP4645622B2 (en) | 2007-06-01 | 2011-03-09 | 住友電気工業株式会社 | GaN crystal growth method |
JP2008303086A (en) * | 2007-06-05 | 2008-12-18 | Sumitomo Electric Ind Ltd | Method for growing nitride semiconductor crystal and nitride semiconductor crystal substrate |
JP2009023853A (en) * | 2007-07-17 | 2009-02-05 | Hitachi Cable Ltd | Group iii-v nitride semiconductor substrate, method for manufacturing the same, and group iii-v nitride semiconductor device |
KR100969812B1 (en) * | 2007-12-12 | 2010-07-13 | 주식회사 실트론 | Manufacturing Method of Gallium Nitride Single Crystalline Substrate Using Self-Split |
JP5391653B2 (en) | 2008-01-15 | 2014-01-15 | 住友電気工業株式会社 | Method for growing aluminum nitride crystal and method for producing aluminum nitride crystal |
JP2010056129A (en) * | 2008-08-26 | 2010-03-11 | Nippon Telegr & Teleph Corp <Ntt> | Substrate used for crystal growth of nitride-based compound semiconductor, and method for crystal growth of nitride-based compound semiconductor |
JP2010222232A (en) * | 2009-02-26 | 2010-10-07 | Kyocera Corp | Single crystal body, single crystal substrate, and production method and production apparatus of single crystal body |
JP5446622B2 (en) * | 2009-06-29 | 2014-03-19 | 住友電気工業株式会社 | Group III nitride crystal and method for producing the same |
JP5233894B2 (en) * | 2009-07-30 | 2013-07-10 | 信越半導体株式会社 | Manufacturing method of nitride semiconductor free-standing substrate |
JP2011199187A (en) * | 2010-03-23 | 2011-10-06 | Hitachi Cable Ltd | Gallium nitride based semiconductor diode |
JP2012227479A (en) * | 2011-04-22 | 2012-11-15 | Sharp Corp | Nitride semiconductor element formation wafer and method of manufacturing the same, and nitride semiconductor element and method of manufacturing the same |
JP2013010681A (en) * | 2011-05-31 | 2013-01-17 | Hitachi Cable Ltd | Gallium nitride substrate, light emitting element, field effect transistor, and method for producing epitaxial film |
EP2890537A1 (en) * | 2012-08-28 | 2015-07-08 | Sixpoint Materials Inc. | Group iii nitride wafer and its production method |
WO2014051692A1 (en) | 2012-09-25 | 2014-04-03 | Sixpoint Materials, Inc. | Method of growing group iii nitride crystals |
JP6140291B2 (en) | 2012-09-26 | 2017-05-31 | シックスポイント マテリアルズ, インコーポレイテッド | Group III nitride wafer, fabrication method and test method |
JP6776711B2 (en) * | 2016-08-08 | 2020-10-28 | 三菱ケミカル株式会社 | GaN single crystal and GaN single crystal manufacturing method |
JP6901844B2 (en) * | 2016-12-02 | 2021-07-14 | 株式会社サイオクス | Nitride crystal substrate manufacturing method and crystal growth substrate |
US10886033B2 (en) * | 2017-09-28 | 2021-01-05 | Regents Of The University Of Minnesota | Conductive films |
JP6916719B2 (en) * | 2017-11-17 | 2021-08-11 | 株式会社トクヤマ | Method for producing Group III nitride single crystal laminate and Group III nitride single crystal laminate |
JP2018154553A (en) * | 2018-06-28 | 2018-10-04 | 住友化学株式会社 | GaN substrate |
JP6595678B1 (en) * | 2018-08-29 | 2019-10-23 | 株式会社サイオクス | Nitride semiconductor substrate, nitride semiconductor substrate manufacturing method, and laminated structure |
JP6595677B1 (en) * | 2018-08-29 | 2019-10-23 | 株式会社サイオクス | Nitride semiconductor substrate manufacturing method, nitride semiconductor substrate, and laminated structure |
JP6595731B1 (en) * | 2018-10-26 | 2019-10-23 | 株式会社サイオクス | Nitride semiconductor substrate manufacturing method, nitride semiconductor substrate, and laminated structure |
JP6595689B1 (en) * | 2018-11-08 | 2019-10-23 | 株式会社サイオクス | Nitride semiconductor substrate manufacturing method, nitride semiconductor substrate, and laminated structure |
JP6646769B1 (en) * | 2019-02-01 | 2020-02-14 | 株式会社サイオクス | Nitride semiconductor substrate, laminated structure, and method of manufacturing nitride semiconductor substrate |
JP7339019B2 (en) * | 2019-05-20 | 2023-09-05 | 住友化学株式会社 | Manufacturing method of nitride semiconductor substrate |
JP7166998B2 (en) * | 2019-09-20 | 2022-11-08 | 株式会社サイオクス | nitride semiconductor substrate |
JP7006751B2 (en) * | 2020-10-07 | 2022-01-24 | 三菱ケミカル株式会社 | GaN single crystal and GaN single crystal manufacturing method |
JP7327532B2 (en) * | 2020-10-07 | 2023-08-16 | 三菱ケミカル株式会社 | GaN Single Crystal and GaN Single Crystal Manufacturing Method |
CN113072906A (en) * | 2021-03-31 | 2021-07-06 | 哈尔滨化兴软控科技有限公司 | Aluminum nitride seed crystal adhesive and preparation method and use method thereof |
TW202332813A (en) * | 2021-04-07 | 2023-08-16 | 日商信越化學工業股份有限公司 | Manufacturing system of laminated body, laminated body, and semiconductor device |
Citations (11)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US5122845A (en) * | 1989-03-01 | 1992-06-16 | Toyoda Gosei Co., Ltd. | Substrate for growing gallium nitride compound-semiconductor device and light emitting diode |
US5290393A (en) * | 1991-01-31 | 1994-03-01 | Nichia Kagaku Kogyo K.K. | Crystal growth method for gallium nitride-based compound semiconductor |
US6488767B1 (en) * | 2001-06-08 | 2002-12-03 | Advanced Technology Materials, Inc. | High surface quality GaN wafer and method of fabricating same |
US20020189532A1 (en) * | 2001-04-12 | 2002-12-19 | Kensaku Motoki | Oxygen doping method to gallium nitride single crystal substrate and oxygen-doped N-type gallium nitride freestanding single crystal substrate |
US20030099866A1 (en) * | 2001-11-29 | 2003-05-29 | Yoshio Takahashi | Magnetic recording medium and its manufacturing method and magnetic recording system using such a magnetic recording medium |
US20040147096A1 (en) * | 2003-01-20 | 2004-07-29 | Matsushita Electric Industrial Co., Ltd. | Method of manufacturing Group III nitride substrate |
US20050023544A1 (en) * | 2003-04-11 | 2005-02-03 | Hitachi Cable, Ltd. | III-V group nitride system semiconductor substrate |
US20050093003A1 (en) * | 2003-10-29 | 2005-05-05 | Hitachi Cable, Ltd. | III-V group nitride system semiconductor substrate |
US20060228819A1 (en) * | 2005-04-11 | 2006-10-12 | Hitachi Cable, Ltd. | Method of making nitride-based compound semiconductor crystal and substrate |
US20060272572A1 (en) * | 2005-06-06 | 2006-12-07 | Sumitomo Electric Industries, Ltd. | Nitride semiconductor substrate and method of producing same |
US20080003786A1 (en) * | 2003-11-13 | 2008-01-03 | Cree, Inc. | Large area, uniformly low dislocation density gan substrate and process for making the same |
Family Cites Families (14)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPH06102598B2 (en) | 1989-01-20 | 1994-12-14 | 株式会社ジャパンエナジー | Method for manufacturing semiconductor device material |
JP2751963B2 (en) | 1992-06-10 | 1998-05-18 | 日亜化学工業株式会社 | Method for growing indium gallium nitride semiconductor |
US5385866A (en) | 1994-06-22 | 1995-01-31 | International Business Machines Corporation | Polish planarizing using oxidized boron nitride as a polish stop |
JPH08139028A (en) * | 1994-11-04 | 1996-05-31 | Ricoh Co Ltd | Vertical vapor growth equipment |
JP4145437B2 (en) | 1999-09-28 | 2008-09-03 | 住友電気工業株式会社 | Single crystal GaN crystal growth method, single crystal GaN substrate manufacturing method, and single crystal GaN substrate |
JP3631724B2 (en) | 2001-03-27 | 2005-03-23 | 日本電気株式会社 | Group III nitride semiconductor substrate and manufacturing method thereof |
JP2003073189A (en) * | 2001-08-31 | 2003-03-12 | Sumitomo Chem Co Ltd | Semiconductor production method and device |
JP2003128499A (en) * | 2001-10-18 | 2003-05-08 | Hitachi Cable Ltd | Method for producing nitride crystal substrate and nitride crystal substrate |
JP2003165798A (en) * | 2001-11-28 | 2003-06-10 | Hitachi Cable Ltd | Method for producing gallium nitride single crystal substrate, free standing substrate for epitaxial growth of gallium nitride single crystal, and device element formed on the same |
JP4117156B2 (en) * | 2002-07-02 | 2008-07-16 | 日本電気株式会社 | Method for manufacturing group III nitride semiconductor substrate |
JP4513326B2 (en) * | 2004-01-14 | 2010-07-28 | 日立電線株式会社 | Nitride semiconductor crystal manufacturing method and nitride semiconductor substrate manufacturing method |
JP4691911B2 (en) | 2004-06-11 | 2011-06-01 | 日立電線株式会社 | III-V nitride semiconductor free-standing substrate manufacturing method |
JP4720125B2 (en) * | 2004-08-10 | 2011-07-13 | 日立電線株式会社 | III-V nitride semiconductor substrate, method of manufacturing the same, and III-V nitride semiconductor |
JP4849296B2 (en) | 2005-04-11 | 2012-01-11 | 日立電線株式会社 | GaN substrate |
-
2005
- 2005-04-11 JP JP2005113416A patent/JP4849296B2/en active Active
- 2005-07-08 US US11/176,687 patent/US20060226414A1/en not_active Abandoned
-
2010
- 2010-04-19 US US12/662,461 patent/US8143702B2/en active Active
Patent Citations (18)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US5122845A (en) * | 1989-03-01 | 1992-06-16 | Toyoda Gosei Co., Ltd. | Substrate for growing gallium nitride compound-semiconductor device and light emitting diode |
US5290393A (en) * | 1991-01-31 | 1994-03-01 | Nichia Kagaku Kogyo K.K. | Crystal growth method for gallium nitride-based compound semiconductor |
US20020189532A1 (en) * | 2001-04-12 | 2002-12-19 | Kensaku Motoki | Oxygen doping method to gallium nitride single crystal substrate and oxygen-doped N-type gallium nitride freestanding single crystal substrate |
US6488767B1 (en) * | 2001-06-08 | 2002-12-03 | Advanced Technology Materials, Inc. | High surface quality GaN wafer and method of fabricating same |
US7182974B2 (en) * | 2001-11-29 | 2007-02-27 | Hitachi Global Storage Technologies Japan, Ltd. | Magnetic recording medium and its manufacturing method and magnetic recording system using such a magnetic recording medium |
US20030099866A1 (en) * | 2001-11-29 | 2003-05-29 | Yoshio Takahashi | Magnetic recording medium and its manufacturing method and magnetic recording system using such a magnetic recording medium |
US20040157083A1 (en) * | 2001-11-29 | 2004-08-12 | Hitachi Global Storage Technologies Japan, Ltd. | Magnetic recording medium and its manufacturing method and magnetic recording system using such a magnetic recording medium |
US20040147096A1 (en) * | 2003-01-20 | 2004-07-29 | Matsushita Electric Industrial Co., Ltd. | Method of manufacturing Group III nitride substrate |
US20050023544A1 (en) * | 2003-04-11 | 2005-02-03 | Hitachi Cable, Ltd. | III-V group nitride system semiconductor substrate |
US20050093003A1 (en) * | 2003-10-29 | 2005-05-05 | Hitachi Cable, Ltd. | III-V group nitride system semiconductor substrate |
US7057204B2 (en) * | 2003-10-29 | 2006-06-06 | Hitachi Cable, Ltd. | III-V group nitride system semiconductor substrate |
US7276779B2 (en) * | 2003-11-04 | 2007-10-02 | Hitachi Cable, Ltd. | III-V group nitride system semiconductor substrate |
US20080003786A1 (en) * | 2003-11-13 | 2008-01-03 | Cree, Inc. | Large area, uniformly low dislocation density gan substrate and process for making the same |
US7323256B2 (en) * | 2003-11-13 | 2008-01-29 | Cree, Inc. | Large area, uniformly low dislocation density GaN substrate and process for making the same |
US20080124510A1 (en) * | 2003-11-13 | 2008-05-29 | Cree, Inc. | Large area, uniformly low dislocation density gan substrate and process for making the same |
US20060228819A1 (en) * | 2005-04-11 | 2006-10-12 | Hitachi Cable, Ltd. | Method of making nitride-based compound semiconductor crystal and substrate |
US7348278B2 (en) * | 2005-04-11 | 2008-03-25 | Hitachi Cable, Ltd. | Method of making nitride-based compound semiconductor crystal and substrate |
US20060272572A1 (en) * | 2005-06-06 | 2006-12-07 | Sumitomo Electric Industries, Ltd. | Nitride semiconductor substrate and method of producing same |
Cited By (33)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US8143702B2 (en) | 2005-04-11 | 2012-03-27 | Hitachi Cable, Ltd. | Group III-V nitride based semiconductor substrate and method of making same |
US20090045072A1 (en) * | 2005-09-06 | 2009-02-19 | Japan Science And Technology Agency | Iii/v group nitride semiconductor, photocatalytic semiconductor device, photocatalytic oxidation-reduction reaction apparatus and execution process of photoelectrochemical reaction |
EP2019155A3 (en) * | 2007-05-02 | 2010-09-22 | Sumitomo Electric Industries, Ltd. | Gallium nitride substrate and gallium nitride film deposition method |
US20080272377A1 (en) * | 2007-05-02 | 2008-11-06 | Sumitomo Electric Industries, Ltd. | Gallium Nitride Substrate and Gallium Nitride Film Deposition Method |
US20080303033A1 (en) * | 2007-06-05 | 2008-12-11 | Cree, Inc. | Formation of nitride-based optoelectronic and electronic device structures on lattice-matched substrates |
US20090127662A1 (en) * | 2007-11-20 | 2009-05-21 | Sumitomo Electric Industries, Ltd. | Group iii nitride semiconductor crystal substrate and semiconductor device |
US20100164070A1 (en) * | 2007-11-20 | 2010-07-01 | Sumitomo Electric Industries, Ltd | Group III Nitride Semiconductor Crystal Substrate and Semiconductor Device |
US20090127663A1 (en) * | 2007-11-20 | 2009-05-21 | Sumitomo Electric Industries. Ltd. | Group iii nitride semiconductor crystal growing method, group iii nitride semiconductor crystal substrate fabrication method, and group iii nitride semiconductor crystal substrate |
EP2065491B1 (en) * | 2007-11-20 | 2019-06-19 | Sumitomo Electric Industries, Ltd. | Gallium nitride semiconductor crystal substrate and semiconductor device |
US8698282B2 (en) | 2007-11-20 | 2014-04-15 | Sumitomo Electric Industries, Ltd. | Group III nitride semiconductor crystal substrate and semiconductor device |
US20140319533A1 (en) * | 2008-08-04 | 2014-10-30 | Goldeneye, Inc. | Flexible semiconductor devices based on flexible freestanding epitaxial elements |
US9171909B2 (en) * | 2008-08-04 | 2015-10-27 | Goldeneye, Inc. | Flexible semiconductor devices based on flexible freestanding epitaxial elements |
US20120018732A1 (en) * | 2009-01-15 | 2012-01-26 | Disco Corporation | Inside reforming substrate for epitaxial growth; crystal film forming element, device, and bulk substrate produced using the same; and method for producing the same |
US20100258812A1 (en) * | 2009-04-13 | 2010-10-14 | Hitachi Cable, Ltd. | Group-iii nitride semiconductor freestanding substrate and manufacturing method of the same |
US8102026B2 (en) * | 2009-04-13 | 2012-01-24 | Hitachi Cable, Ltd. | Group-III nitride semiconductor freestanding substrate and manufacturing method of the same |
US20100272141A1 (en) * | 2009-04-23 | 2010-10-28 | Hitachi Cable, Ltd. | Nitride semiconductor freestanding substrate and manufacturing method of the same, and laser diode |
US20110147759A1 (en) * | 2009-12-18 | 2011-06-23 | Hitachi Cable, Ltd. | Group iii nitride semiconductor substrate and manufacturing method of the same |
US10060047B2 (en) | 2011-09-12 | 2018-08-28 | Sumitomo Chemical Company, Limited | Nitride semiconductor crystal producing method including growing nitride semiconductor crystal over seed crystal substrate |
CN104115258A (en) * | 2012-02-20 | 2014-10-22 | 三垦电气株式会社 | Epitaxial substrate, semiconductor device, and method for manufacturing semiconductor device |
US20140061660A1 (en) * | 2012-08-30 | 2014-03-06 | Kabushiki Kaisha Toshiba | Semiconductor light emitting device and manufacturing method thereof |
US9312444B2 (en) * | 2012-08-30 | 2016-04-12 | Kabushiki Kaisha Toshiba | Semiconductor light emitting device and manufacturing method thereof |
CN105026625A (en) * | 2013-02-08 | 2015-11-04 | 并木精密宝石株式会社 | GaN substrate and method for manufacturing GaN substrate |
US10364510B2 (en) | 2015-11-25 | 2019-07-30 | Sciocs Company Limited | Substrate for crystal growth having a plurality of group III nitride seed crystals arranged in a disc shape |
US10260165B2 (en) | 2016-01-05 | 2019-04-16 | Osaka University | Method for manufacturing nitride crystal substrate and substrate for crystal growth |
US10584031B2 (en) | 2016-03-08 | 2020-03-10 | Sciocs Company Limited | Nitride crystal substrate |
US11810782B2 (en) | 2016-08-08 | 2023-11-07 | Mitsubishi Chemical Corporation | Conductive C-plane GaN substrate |
US11421344B2 (en) | 2018-02-23 | 2022-08-23 | Sumitomo Electric Industries, Ltd. | Gallium nitride crystal substrate |
CN111356794A (en) * | 2018-02-23 | 2020-06-30 | 住友电气工业株式会社 | Gallium nitride crystal substrate |
CN110499533A (en) * | 2018-05-16 | 2019-11-26 | 赛奥科思有限公司 | The manufacturing method of element nitride crystal substrate and element nitride crystal substrate |
US11732380B2 (en) * | 2018-05-16 | 2023-08-22 | Sumitomo Chemical Company, Limited | Nitride crystal substrate and method for manufacturing the same |
US20200040482A1 (en) * | 2018-05-16 | 2020-02-06 | Sciocs Company Limited | Nitride crystal substrate and method for manufacturing the same |
US11908688B2 (en) | 2018-08-29 | 2024-02-20 | Sumitomo Chemical Company, Limited | Method for manufacturing nitride semiconductor substrate, nitride semiconductor substrate and layered structure |
CN112151355A (en) * | 2019-06-28 | 2020-12-29 | 东莞市中镓半导体科技有限公司 | Method for manufacturing gallium nitride self-supporting substrate |
Also Published As
Publication number | Publication date |
---|---|
US8143702B2 (en) | 2012-03-27 |
JP2006290676A (en) | 2006-10-26 |
US20100200955A1 (en) | 2010-08-12 |
JP4849296B2 (en) | 2012-01-11 |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
US8143702B2 (en) | Group III-V nitride based semiconductor substrate and method of making same | |
US7271404B2 (en) | Group III-V nitride-based semiconductor substrate and method of making same | |
US7981713B2 (en) | Group III-V nitride-based semiconductor substrate, group III-V nitride-based device and method of fabricating the same | |
US7687824B2 (en) | Method of improving surface flatness of group-III nitride crystal, substrate for epitaxial growth, and semiconductor device | |
US7847313B2 (en) | Group III-V nitride-based semiconductor substrate and group III-V nitride-based light emitting device | |
US7728323B2 (en) | Nitride-based semiconductor substrate, method of making the same and epitaxial substrate for nitride-based semiconductor light emitting device | |
US20070176199A1 (en) | Nitride-based group III-V semiconductor substrate and fabrication method therefor, and nitride-based group III-V light-emitting device | |
US20060228870A1 (en) | Method of making group III-V nitride-based semiconductor crystal | |
TWI437637B (en) | Method for manufacturing gallium nitride single crystalline substrate using self-split | |
US7253499B2 (en) | III-V group nitride system semiconductor self-standing substrate, method of making the same and III-V group nitride system semiconductor wafer | |
US20070138505A1 (en) | Low defect group III nitride films useful for electronic and optoelectronic devices and methods for making the same | |
US20070215901A1 (en) | Group III-V nitride-based semiconductor substrate and method of fabricating the same | |
JP2011006319A (en) | Vicinal gallium nitride substrate for high quality homoepitaxy | |
JP2007277077A (en) | Gallium nitride-based material and its manufacturing method | |
US7348278B2 (en) | Method of making nitride-based compound semiconductor crystal and substrate | |
US8039130B2 (en) | Method of forming group-III nitride crystal, layered structure and epitaxial substrate | |
JP4333466B2 (en) | Manufacturing method of semiconductor substrate and manufacturing method of free-standing substrate | |
JP4633962B2 (en) | Manufacturing method of nitride semiconductor substrate | |
JP2000150388A (en) | Iii nitride semiconductor thin film and manufacture thereof | |
JP6117821B2 (en) | Composite substrate and functional element | |
JPH10229218A (en) | Manufacture of nitride semiconductor substrate and nitride semiconductor substrate | |
KR100834698B1 (en) | Method of forming gan layer and gan substrate manufactured using the same | |
JP2010278470A (en) | Substrate for growing group-iii nitride semiconductor, epitaxial substrate for group-iii nitride semiconductor, group-iii nitride semiconductor element, stand-alone substrate for group-iii nitride semiconductor, and methods for manufacturing the same | |
JP2004128332A (en) | Boron phosphide single crystal substrate, its manufacturing method, and boron phosphide-based semiconductor element | |
JP2006120855A (en) | Group iii-v nitride semiconductor epitaxial wafer |
Legal Events
Date | Code | Title | Description |
---|---|---|---|
AS | Assignment |
Owner name: HITACHI CABLE, LTD., JAPAN Free format text: ASSIGNMENT OF ASSIGNORS INTEREST;ASSIGNOR:OSHIMA, YUICHI;REEL/FRAME:016855/0293 Effective date: 20050719 |
|
STCB | Information on status: application discontinuation |
Free format text: ABANDONED -- FAILURE TO RESPOND TO AN OFFICE ACTION |