DE102007061481A1 - A radiation-emitting semiconductor component with a vertical emission direction and method for producing a radiation-emitting semiconductor component - Google Patents

Abstract

The invention relates to a radiation-emitting semiconductor component (1) with a vertical emission direction, which has a semiconductor body (2) with a semiconductor layer sequence. In the semiconductor layer sequence, a pump region (3) provided for generating a pump radiation is formed. Arranged on the pump region (3) is an emission region (4) provided for generating an emission radiation. In the semiconductor device, a coupling structure (7) is formed. Furthermore, a method for producing a radiation-emitting semiconductor component (1) is specified.

Description

The radiation Semiconductor device with vertical emission direction and method for Production of a radiation-emitting semiconductor component The present application relates to a radiation-emitting semiconductor component with vertical emission direction and a method for manufacturing one radiation-emitting semiconductor conductor component with vertical Emission direction.

optical pumped semiconductor laser with vertical emission direction, for example Disk laser, which together with a pump laser in a compact design accomplished sometimes have high absorption losses within the laser on.

A The object is a radiation-emitting semiconductor component indicate with vertical emission direction, which together with the pump laser designed in a compact design is and has improved properties. Furthermore, a method for producing a radiation-emitting semiconductor component be specified.

These Task is by a semiconductor device or a Solved method according to the independent claims. Advantageous embodiments and further developments are the subject of the dependent claims.

According to one embodiment has a radiation-emitting semiconductor device with vertical Emission direction a semiconductor body with a semiconductor layer sequence on. In the semiconductor layer sequence is a for generating a Pump radiation provided pumping area formed. On the pumping area an emission area provided for generating an emission radiation is arranged. In the semiconductor device, a coupling structure is formed.

The vertical emission direction is vertical to a main extension direction of the semiconductor layers of the semiconductor layer sequence. During operation of the radiation-emitting semiconductor component the pump radiation by means of the coupling structure in the emission area coupled. The pumping area and the emission area are superimposed arranged, giving a compact design of the radiation-emitting Semiconductor device simplified. The pumping area and the emission area can this largely independent be designed from each other. The efficiency of radiation generation can be increased.

Under a coupling structure is understood in particular as a structure in the lateral direction, ie in a main plane of extension the semiconductor layers of the semiconductor body, and extends at the a part of the incident radiation due to reflection, scattering and / or diffraction in a direction different from the original direction is steered. Furthermore, the coupling structure preferably in lateral direction a plurality of juxtaposed Structural elements on. The structural elements of the coupling structure point preferably a feature size in the range the wavelength, about between the inclusive 0.1 times and including Twenty times, the pump radiation in the material of the semiconductor body.

in the Operation of the semiconductor device preferably propagates the pump radiation in a lateral direction. The pump radiation and the emission radiation So they propagate in different ways, especially to each other vertical, upright directions. Further preferred is the coupling structure intended for the partially propagating in the lateral direction pump radiation into the emission area.

In According to a preferred development, the coupling structure is provided for a part of the propagating in the lateral direction pump radiation in an oblique or perpendicular to the lateral direction Direction, in particular to the emission area, to redirect. through The coupling structure is thus the pump radiation influenced such that for a part of the pump radiation changes the propagation direction. This diverted portion of the pump radiation has a wave vector, in one of the original ones lateral direction shows different direction. Preferably shows the wave vector of the diverted portion of the pump radiation from the Main extension plane of the semiconductor layers of the semiconductor body out.

In In a preferred embodiment, the pumping area protrudes laterally Direction at least partially beyond the emission range. In a plan view of the radiation-emitting semiconductor component the pumping area is therefore only partially covered by the emission area. An efficient generation of pump radiation of high radiation power is thereby simplified.

Farther Preferably, the coupling structure is arranged such that of the Coupling structure in the vertical direction deflected radiation directly can get into the emission area. Conveniently, the coupling structure overlaps in a plan view of the radiation-emitting semiconductor component, preferably Completely, with the emission range. An efficient optical pumping of the emission range is so simplified.

During operation of the semiconductor component, the pump radiation is preferably by means of reflection and / or diffraction coupled to the coupling structure in the emission region. The pump radiation coupled into the emission region preferably runs predominantly, for example to an intensity component of at least 50%, at an angle of at most 20 ° to the vertical direction.

The Pump radiation coupled into the emission region can determine the emission range optically pump. In the optically pumped emission region, preferably coherent, Radiation can be generated with a given emission wavelength.

In In a preferred embodiment, the coupling structure is on the Emission region facing away from the pump region arranged. Such a coupling structure is opposite to one between the pumping area and the emission region arranged coupling structure simplified produced.

in this connection the coupling structure is preferably for operation in reflection provided, that is, the impinging on the coupling structure and on the coupling structure reflected or diffracted radiation components are predominantly on the same side of the coupling structure.

In Another preferred embodiment is the coupling structure along the lateral direction periodically or at least largely periodically formed. A largely periodic coupling structure is also called a quasi-periodic coupling structure.

For a period length L of the periodic or quasi-periodic coupling structure, ie the length after which the basic structure of the coupling structure repeats, the following preferably applies: (N - 0.4) · λ ≦ L ≦ (N + 0.4) · λ, where N is a positive integer and λ is the wavelength of the pump radiation in the region of the coupling structure, ie the wavelength in vacuum divided by the refractive index in the region of the coupling structure.

at a quasi-periodic coupling structure corresponds to the period length the mean distance of the structural elements, with adjacent structural elements at least partially arranged in a deviating distance are.

Especially For example, the coupling structure may be used as a diffraction grating, preferably as a diffraction grating be carried out a one-dimensional diffraction grating.

The wave vector of a diffracted wave k _S results from the so-called Bragg condition by the equation k s = k i + G, where k _{i is} the wave vector of the incident radiation and G is a reciprocal lattice vector. In the case of a one-dimensional diffraction grating, G, the amount of the reciprocal lattice vector G, is linked to the lattice constant a of the diffraction grating along the diffraction grating via the condition G = 2π / a. For k _i , the magnitude of the wave vector of the incident wave, k _i = n * 2π / λ _p , where n is the refractive index of the material in which the wave propagates and λ _{p is} the vacuum wavelength of the pump radiation.

In the case where the radiation diffracted into the first order is perpendicular to the diffraction grating, ie for a vanishing fraction of the wave vector along the diffraction grating (k _s = 0), a lattice constant of a = λ _p / n results.

By a coupling structure whose period length of the wavelength of Pump radiation in the coupling structure corresponds, so can the propagating in the lateral direction pump radiation in the first order be bent in the vertical direction.

Prefers is a period length the coupling structure between the inclusive of 0.6 times and 1.4 times inclusive the wavelength the pump radiation in the coupling structure, which is the above Formula for the period length L in the case N = 1 corresponds. Particularly preferably, the period length is between including 0.8 times and including 1.2 times, the wavelength the pump radiation in the coupling structure.

In an alternative embodiment, the coupling structure is according to a Random structure formed. In this case, the structural elements the coupling structure arranged at variable distances from each other, wherein the arrangement may be free of periodicity.

In In a preferred embodiment, the coupling structure is by means of side by side arranged recesses formed. In particular, the recesses periodically, quasi-periodically or according to one Random structure can be arranged.

A lateral extent of the recesses is still preferred between including 0.3 times and including 0.7 times, more preferably between 0.4 times and including 0.6 times, for example 0.5 times, the period length.

Furthermore, the lateral extent the recesses are preferably between 0.3 times inclusive and 0.7 times inclusive, more preferably between 0.4 times and 0.6 times, for example 0.5 times, the wavelength of Pump radiation in the coupling structure.

Farther Preferably, the recesses are trench-like. in this connection extends a main extension direction of the recesses in each case vertically to the lateral direction and perpendicular to the vertical emission direction. In this way, by means of the recesses, a one-dimensional diffraction grating be formed.

In a variant embodiment, the recesses have vertically extending Side flanks on. With recesses in the lateral direction on both sides bounded by vertical side flanks, can be on the side flanks for the In the lateral direction propagating pump radiation a particularly sharp Refractive index jump can be achieved.

Of the Cross-section of the recesses can take virtually any shape. In particular, you can the recesses a polygonal or at least partially curved basic shape exhibit. Furthermore, the coupling structure along the lateral Direction, for example, sawtooth be structured.

In In a further preferred embodiment, the recesses extend in the semiconductor body into it. The recesses are thus at least partially formed in the semiconductor body. The in the lateral direction in the semiconductor body propagating pump radiation can be redirected so simplified by the coupling structure.

In In a preferred embodiment, the recesses are at least partially with a filler filled. The filling material has expediently a refractive index different from the refractive index of the semiconductor body. Further preferred is the filler material for the pump radiation permeable educated.

Further can the filler material contain a dielectric material. For example, the filling material contain an oxide, a nitride or an oxynitride or from a consist of such material.

alternative or in addition can the filler material contain a metal. In this way, the reflectivity of the coupling structure be increased.

In In a preferred embodiment, the coupling structure is in vertical Direction executed in such a way that a predetermined proportion of the pump radiation in the emission area is coupled. The stronger the coupling structure in the vertical direction with the extent of Pump radiation in the vertical direction overlaps, the larger it can be the proportion of pump radiation coupled into the emission area be. On the other hand, the overlap the coupling structure with the pump radiation in the vertical direction be sufficiently low to sufficient propagation of the pump radiation to ensure in a lateral direction.

In In a preferred embodiment, the pumping area is in a waveguide arranged, wherein the waveguide provided for guiding the pump radiation is. The waveguide is preferably between cladding layers arranged, each having a refractive index, the smaller is the refractive index of that adjacent to the cladding layer Waveguide layers.

The Coupling structure preferably projects in the vertical direction in the waveguide into it. Preferably, the coupling structure protrudes in the vertical direction at most 30%, more preferably not more than 20%, most preferably at most 10%, the vertical extent of the waveguide in the waveguide into it. Only a small disturbance The lateral propagation of the pump radiation can thus at the same time efficient deflection of the pump radiation into the emission area be achieved.

The Coupling structure may also be spaced from the waveguide. Here is a distance of the coupling structure of a nearest Limitation of the waveguide in the vertical direction preferably at most as big as the vertical extent of the waveguide. Further preferred is the distance at most 10 μm, especially preferably at most 5 μm.

In In one embodiment variant, the emission range is monolithic in the semiconductor body integrated. The emission area and the pumping area can thus in a common manufacturing step, for example an epitaxial Deposition, such as MOVPE or MBE, are produced.

In an alternative embodiment variant is the emission range separately from the semiconductor body accomplished and preferably on the semiconductor body attached. In this case, you can the emission area and the pumping area are made separately from each other and subsequently positioned to each other.

In a further preferred embodiment, a mirror is formed between the emission region and the pump region. The mirror is in particular intended to reflect the emission radiation propagating in the vertical direction In this case, the mirror can form a resonator end mirror for the emission radiation.

Farther Preferably, the mirror for the pump radiation to a lower reflectivity than for the emission radiation. A Coupling of the pump radiation in the emission range is characterized simplified. Preferably, the reflectivity for the emission radiation at least 80%, more preferably at least 90%. The reflectivity for the pump radiation is preferably at most 30%, most preferably at most 20%.

Of the Mirror can be multi-layered. In particular, the Mirror designed as a Bragg mirror be.

Farther For example, the mirror can be monolithically integrated into the semiconductor body. The mirror can therefore be formed by means of semiconductor layers.

In In another preferred embodiment, the pumping area and / or Emission range a III-V compound semiconductor material. With III-V compound semiconductor materials can achieved high internal quantum efficiencies in radiation generation become.

In Another preferred embodiment includes the emission area and / or the pumping area a quantum structure. The name quantum structure includes in the context of the application in particular any structure, at the carrier by confinement quantization their energy states can learn. In particular, the term quantum structure does not include information about the dimensionality the quantization. It thus includes, among other quantum wells, quantum wires and Quantum dots and any combination of these structures.

In Another preferred embodiment is the semiconductor device for the Operation provided with an external resonator. The external resonator may be formed, for example, by means of a mirror, the from the Semiconductor body is spaced. The emission radiation thus passes through a free-jet area between the semiconductor body and the external mirror. In this free jet area can continue preferably a nonlinear optical Be arranged element. The nonlinear optical element can be used for Frequency mixing and / or frequency multiplication, such as frequency doubling, be provided the emission radiation.

According to one embodiment a method for producing a radiation-emitting semiconductor component with vertical emission direction is a semiconductor body with a semiconductor layer sequence, the one for generating a pump radiation provided pumping area, deposited. One to the generation an emitting radiation emission area and the pumping area be on top of each other arranged or on top of each other deposited. A coupling structure is formed and the radiation-emitting semiconductor component will be completed. The order of the to be performed Process steps here, if appropriate, also of the order this list differ.

With The described method can be a radiation-emitting semiconductor component with vertical emission direction, which is already a pump radiation source includes, be made in a simplified manner.

At the Forming the coupling structure is preferably material of the semiconductor body and / or material from on the semiconductor body arranged layers removed in areas. This can be, for example by means of a wet-chemical or a dry-chemical process respectively.

Of the Semiconductor body is, preferably epitaxially, for example by MBE or MOVPE on deposited on a growth substrate. Before forming the coupling structure The growth substrate can be removed. The formation of a coupling structure on the side of the pumping area facing away from the emission area is so simplified.

The Growth substrate can, for example, mechanically, for example by means of grinding, Lapping or polishing, or chemical, such as by wet chemical or dry chemical etching, be removed. Alternatively, the growth substrate may be formed by coherent radiation, about laser radiation, to be removed.

In a variant of the design is the emission range as part the semiconductor layer sequence of the semiconductor body deposited. Especially can the emission area and the pumping area in a common epitaxy step getting produced. In this case, first the pumping area and subsequently the emission area are deposited or vice versa. On one additional Epitaxy step for the formation of a separate, semiconductor-based, Emission range can thus be waived.

In an alternative embodiment variant is the emission range prefabricated and is attached to the semiconductor body. The fastening can, for example, cohesively, take place for example by means of a connecting layer. The connection layer can for example, contain an adhesive.

The method described is for the manufacture ment of a semiconductor device described above particularly suitable. In the context of the semiconductor device executed features can therefore also be used for the process and vice versa.

Further Features, advantageous embodiments and expediencies result from the following description of the embodiments in conjunction with the figures.

It demonstrate:

1 a first embodiment of a radiation-emitting semiconductor device in a schematic sectional view,

2 A second exemplary embodiment of a radiation-emitting semiconductor component in a schematic sectional view,

3 A third embodiment of a radiation-emitting semiconductor device in a schematic sectional view,

4 the result of a simulation of the deflected intensity of the pump radiation as a function of the angle θ to the vertical direction,

5 the result of a corresponding simulation for a component without a coupling structure,

6 a result of a simulation of the deflected intensity of the pump radiation in a course along a lateral direction, and

the 7A to 7E an embodiment of a method for producing a radiation-emitting semiconductor device based on some schematically illustrated in sectional view intermediate steps.

Same, similar and equally acting elements are in the figures with provided the same reference numerals.

The Figures are schematic representations and therefore not absolutely true to scale. Rather, you can comparatively small elements and in particular layer thicknesses for Exaggeration exaggerated shown big be.

1 shows a first embodiment of a radiation-emitting semiconductor device with a vertical emission direction. The semiconductor device 1 comprises a semiconductor body 2 with a semiconductor layer sequence. The semiconductor layer sequence forms the semiconductor body and is preferably produced epitaxially, for example by means of MOVPE or MBE.

In the semiconductor layer sequence of the semiconductor body 2 is a pumping area provided for generating a pump radiation 3 educated. Furthermore, the semiconductor layer sequence has an emission region 4 on, with the pumping area 3 and the emission area 4 are arranged one above the other. The emission area 4 and the pumping area 3 are therefore monolithically integrated into a common semiconductor body.

The pumping area 3 is in the lateral direction on opposite sides of two side surfaces 30 limited. The pump radiation propagates between these side surfaces in the lateral direction. To increase the reflectivity of the side surfaces 30 These may each be provided with a coating, for example with dielectric layers, which may be designed as Bragg mirrors. This coating is in the 1 not explicitly shown.

Furthermore, the radiation-emitting semiconductor component has a coupling structure 7 on. The coupling structure 7 is by means of recesses 71 formed, which is in the semiconductor body 2 extend into it. The coupling structure 7 is on the emission area 4 opposite side of the pumping area 3 arranged.

The pumping area 3 is in a waveguide 35 arranged. The waveguide has a first waveguide layer 351 and a second waveguide layer 352 on, each adjacent to the pumping area.

On both sides of the pumping area 3 each adjacent to a cladding layer 31 or a further cladding layer 32 to the waveguide 35 at. The cladding layers 31 . 32 Expediently have a refractive index which is smaller than the refractive index of the waveguide layers 351 . 352 , By means of the waveguide 35 the pump radiation propagating in the lateral direction is guided.

The recesses 71 the coupling structure 7 extend from the emission area 4 opposite side of the pumping area 3 in the semiconductor body 2 into it. In particular, the recesses extend 71 in the vertical direction in the waveguide 35 into it. The recesses are preferably designed as trench-like recesses, wherein a main extension direction of the recesses in each case extends perpendicular to the lateral direction in which propagates the pump radiation, and further perpendicular to the vertical direction.

During operation of the radiation-emitting semiconductor component 1 becomes a part of the propagating in the lateral direction pump radiation by means of the coupling structure 7 in the direction of the emission area 4 diverted. The coupling structure can be embodied here as a one-dimensional diffraction grating. Preferably, the diffraction grating is periodically or substantially periodically executed. For a period length L of the coupling structure is preferably (N - 0.4) · λ ≦ L ≦ (N + 0.4) · λ, where λ is the wavelength of the pump radiation in the coupling structure and N is a positive integer. Particularly preferably, N = 1, so that the period length of the coupling structure is between 0.6 times and 1.4 times the wavelength of the pump radiation in the region of the coupling structure. Most preferably, the period length is between 0.8 times and 1.2 times the wavelength of the pump radiation in the region of the coupling structure.

For example can the period length at a vacuum wavelength the pump radiation of 920 nm and a refractive index of 3.4 about 270 nm.

through a diffraction grating whose period length L is the wavelength of Pump radiation corresponds to a part of the pump radiation at the Diffraction grating deflected in the first order in the vertical direction become. In this way, a part of the pump radiation in the emission area be coupled.

From the embodiment shown deviating, the coupling structure can also be considered a quasi-periodic Diffraction grating executed be.

Alternatively, the recesses 71 also be arranged according to a random structure.

Prefers extends the pump radiation coupled into the emission area predominantly at an angle of at most 20 ° to the vertical direction.

The means of coupling structure 7 redirected pump radiation is coupled into the emission area. By means of the absorbed pump radiation, the emission area is optically pumped.

In a plan view of the semiconductor device 1 indicates the pumping area 3 a larger lateral extent than the emission range 4 , In this way, the generation of high intensity pump radiation is simplified.

Between the pumping area 3 and the emission area 4 is a mirror 5 arranged. The mirror is monolithic in the semiconductor layer sequence of the semiconductor body 2 integrated. The mirror 5 is multi-layered and has a plurality of semiconductor layer pairs, each having a semiconductor layer 51 and another semiconductor layer 52 include. These semiconductor layers have different refractive indices from each other, so that the semiconductor layer pairs form a Bragg mirror.

The mirror is preferably designed such that the reflectivity for those in the emission area 4 generated radiation is greater than for those in the pumping area 3 generated pump radiation.

Prefers is the reflectivity for the emission radiation at least 80%, more preferably at least 90%. The reflectivity for the pump radiation is preferably at most 30%, most preferably at most 20%.

In this way, during operation of the semiconductor component in the emission region 4 generated radiation efficiently at the mirror 5 be reflected. An entry of the emission radiation into the pump region and subsequently an impingement on the coupling structure 7 can be avoided this way. Furthermore, the proportion of emissions in the area 4 coupled pump radiation the higher the lower the reflectivity of the mirror for the pump radiation.

On the pumping area 3 opposite side of the emission area 4 is a window layer 25 educated. The window layer is expediently designed to be permeable to the emission radiation. A surface of the window layer facing away from the emission area 25 closes off the semiconductor body in the vertical direction and forms a radiation passage area 20 for the emission radiation.

By means of an external mirror 8th an external resonator is formed. The radiation-emitting semiconductor component 1 is therefore intended for operation with an external resonator.

Deviating from the radiation-emitting component on the pumping area 3 opposite side of the emission area 4 have another mirror. This further mirror can be integrated in or arranged on the semiconductor body. An external resonator can be dispensed with in this case.

The recesses 71 the coupling structure 7 are arranged side by side. Furthermore, the recesses have vertically extending side edges 710 on. In the vertical direction is the coupling structure 7 Preferably carried out such that a predetermined proportion of the pump radiation is coupled into the emission region.

A lateral extent of the recesses is still preferred between including 0.3 times and including 0.7 times, more preferably between 0.4 times and including 0.6 times, for example 0.5 times, the period length. at a vacuum wavelength the pump radiation of 920 nm, the expansion, for example 135 nm.

In the illustrated embodiment, the coupling structure protrudes in the vertical direction in the waveguide 35 into it. The further the coupling structure extends into the waveguide, the stronger the interaction of the pump radiation with the coupling structure 7 , so that a larger proportion of the pump radiation in the emission area 4 can be coupled.

On the other hand, the coupling structure causes 7 a disturbance of the waveguide. A coupling structure, in the vertical direction by at most 30% of the vertical extent of the waveguide 35 protruding into this has proved to be useful. The coupling structure preferably projects into the waveguide by at most 20%, more preferably by at most 10%, of the vertical extent of the waveguide.

Deviating from the embodiment shown, the coupling structure 7 also from the waveguide 35 be spaced. This is particularly expedient if a comparatively large part of the transversal mode of the pump radiation extends outside the waveguide. For a sufficiently large proportion of the coupling structure 7 deflected pump radiation is the distance of the coupling structure from a nearest boundary of the waveguide in the vertical direction at most as large as the vertical extent of the waveguide. Further preferably, this distance is at most 10 microns, more preferably at most 5 microns.

The recesses 71 The coupling structure may be completely or only partially filled with a filling material. Preferably, the filling material is designed to be permeable to the pump radiation. An absorption of the pump radiation by the filling material can thus be avoided or at least reduced. For example, the filler material may include a dielectric material such as an oxide such as silicon oxide or titanium oxide, a nitride such as silicon nitride, or an oxynitride such as silicon oxynitride.

Farther has the filler expediently a refractive index, the refractive index of the adjacent Semiconductor material is different. The bigger the difference between these Refractive indices is the stronger is the influence of the coupling structure on the pump radiation at the same remaining parameters for the geometric structure of the coupling structure.

alternative or in addition can the filler material also contain a metal. In this way, the reflectivity of the coupling structure be increased.

Furthermore, the radiation-emitting semiconductor component has 1 a first contact 61 and a second contact 62 on. The contacts are arranged such that in the operation of the semiconductor device by applying an external electrical voltage charge carriers from two different sides in the pumping area 3 can be injected and recombine there as electron-hole pairs under emission of radiation.

The contacts 61 . 62 preferably contain a metal, such as gold, silver, titanium, platinum, nickel or aluminum or a metallic alloy with at least one of said materials.

The mirror 5 is outside of an injection path of charge carriers from the contacts 61 . 62 arranged in the pumping area. The mirror can thus be made electrically insulating. An absorption of the pump radiation in the mirror can thus be avoided or at least reduced.

Deviating from an arrangement is conceivable in which the mirror 5 is disposed within the injection path of charge carriers. In this case, the mirror is preferably electrically conductive.

Furthermore, the coupling structure overlaps 7 in plan view of the semiconductor device 1 , preferably completely, with the emission range 4 ,

The coupling structure is thus formed in a region in which of the coupling structure 7 In the vertical direction deflected pump radiation directly into the emission area 4 can be coupled. A disturbance of the waveguide 35 is thus limited to areas in which an efficient coupling of the pump radiation in the emission area 4 can be done.

Of the described structure of the semiconductor device is for a variety of semiconductor materials suitable. The pumping area and / or preferably contains the emission region is a III-V compound semiconductor material.

III-V compound semiconductor materials are used for generating radiation in the ultraviolet (In _x Ga _y Al _1-xy N) over the visible (In _x Ga _y Al _1-xy N, in particular for blue to green radiation, or In _x Ga _y Al _{1- xy} P, especially for yellow to red radiation) to In the infrared (In _x Gay Al _1-xy As) spectral range particularly suitable. In each case 0 ≦ x ≦ 1, 0 ≦ y ≦ 1 and x + y ≦ 1, in particular with x ⇒ 1, y ⇒ 1, x ⇒ 0 and / or y ⇒ 0. With III-V compound semiconductor materials, in particular the said material systems, can be achieved in the generation of radiation advantageously high internal quantum efficiencies.

Of the Emission area and / or the pumping area preferably contains a quantum structure. in this connection The quantum structure can each have one or more quantum layers exhibit.

The Designation Quantum structure includes in the context of the application in particular any structure, in the case of carriers by confinement quantization their energy states can learn. In particular, the term quantum structure does not include information about the dimensionality of the quantization. It thus includes, among other things, quantum wells, quantum wires and quantum dots and any combination of these structures.

following By way of example, a layer structure for a semiconductor body is described, its emission range for the generation of radiation of a wavelength of 1050 nm provided is.

The pumping area 3 has an In _0.13 Ga _{0, 87} As quantum layer having a thickness of 6.5 nm. The waveguide layer 351 is executed in two layers. To the quantum layer 3 Adjacent to a first Al _0.10 Ga _0.90 As semiconductor layer with a thickness of 73.57 nm. A second semiconductor layer of the waveguide layer 351 is an Al _0.23 Ga _0.77 As semiconductor layer with a thickness of 485 nm. The second waveguide layer 352 is corresponding to the first waveguide layer 351 formed, the from the pumping area 3 spaced apart Al _0.23 Ga _0.77 As semiconductor layer thereof has a thickness of 788.79 nm.

The each to the waveguide 35 adjacent cladding layers 31 and 32 are each Al _0.47 Ga _0.53 As semiconductor layers having a thickness of 1000 nm.

The on different sides of the pumping area 3 arranged semiconductor layers expediently have a mutually opposite conductivity type. For example, those on the emission area 4 facing side of the pumping area 3 arranged semiconductor layers 351 . 31 p-doped and those on the emission area 4 opposite side of the pumping area 3 arranged semiconductor layers 352 . 32 be n-doped or vice versa.

The mirror 5 is using as a Bragg mirror 30 Semiconductor layer pairs executed. The semiconductor layer pairs each comprise an AlAs semiconductor layer 51 with a thickness of 88 nm and a GaAs semiconductor layer 52 with a thickness of 75 nm.

The emission range provided for generating the emission radiation 4 has a sequence of 14 quantum layers 41 on, between each of which a barrier layer 42 is trained. The quantum layer 41 is each embodied as an InGaAs semiconductor layer with a thickness of 10 nm. The barrier layer comprises a semiconductor layer pair each having a GaAsP semiconductor layer with a thickness of 48 nm and an AlGaAs semiconductor layer with an aluminum content of 10% and a thickness of 93 nm.

On the pumping area 3 opposite side of the emission area 4 is a window layer 25 formed, which is permeable to the radiation generated in the emission area. The window layer is designed in two layers, with an AlGaAs semiconductor layer having an aluminum content of 10% and a thickness of 308 nm adjoining the emission area. A GaP semiconductor layer with a thickness of 551 nm closes the semiconductor body 2 and forms the radiation passage area 20 ,

By a variation of the semiconductor layer parameters, in particular by a variation of the material compositions and the layer thicknesses the quantum layers can the emission wavelengths the pumping range and the emission range are set within wide limits become.

A second exemplary embodiment of a radiation-emitting semiconductor component is shown in FIG 2 schematically shown in sectional view. This second embodiment corresponds essentially to that in connection with FIG 1 illustrated first embodiment. In contrast to this, the coupling structure 7 a sawtooth-like structure. As described in connection with the first embodiment, the recesses 71 that the coupling structure 7 form, in the semiconductor body 2 formed and extend into the waveguide 35 into it. A period length of the coupling structure is preferably between 0.6 times and 1.4 times that in the pumping area 3 generated pump radiation in the material of the semiconductor body 2 ,

Deviating from the coupling structure, it may also be designed in such a way that it deflects the pump radiation mainly due to reflection at the coupling structure. In this case, the coupling structure preferably has side surfaces which are inclined with respect to the vertical direction. Here, the coupling structure does not necessarily perio be educated. Also, a periodic structure, such as a sawtooth structure whose period length is considerably greater than the wavelength of the pump radiation, about at least five times as large, may be suitable here.

A third exemplary embodiment of a radiation-emitting semiconductor component is shown in FIG 3 schematically shown in sectional view. This third embodiment corresponds essentially to that in connection with FIG 1 described first embodiment. In contrast to this, the radiation-emitting component has a further semiconductor body with a further semiconductor layer sequence 200. on, with the emission range 4 and the mirror 5 in this further semiconductor body 200. are formed. The emission area 4 and the pumping area 3 are therefore not monolithically integrated into a common semiconductor body. The further semiconductor body 200. is with the semiconductor body 2 cohesively by means of a connecting layer 9 connected. The connection layer 9 is suitably designed to be permeable to the pump radiation and may, for example, contain an adhesive.

The mirror 5 may differ from this embodiment also on the semiconductor body 200. or on the semiconductor body 2 be educated. In this case, the mirror may be formed by means of dielectric layers which are deposited on the prefabricated semiconductor body or the prefabricated further semiconductor body, for instance by means of vapor deposition or sputtering. Alternatively, the mirror may also be in the semiconductor body 2 with the pumping area 3 be integrated.

The semiconductor body 2 and the further semiconductor body 200. can be made separately from each other and subsequently attached to each other. The production of the semiconductor body with the pumping area 3 and the semiconductor body with the emission area 4 can therefore be largely independent of each other.

Furthermore, in contrast to the first exemplary embodiment, between the radiation-emitting semiconductor component 1 and the external mirror 8th a nonlinear optical element 85 , such as a nonlinear optical crystal. Non-linear optical processes, in particular frequency multiplication, such as frequency doubling, can be used in the emission area 4 generated emission radiation are at least partially converted into radiation of a different wavelength.

Of course, a radiation-emitting semiconductor component according to one of the in connection with the in the 1 and 2 be described embodiments for operation with a non-linear optical element.

4 shows the result of a simulation of the deflected by the coupling structure intensity as a function of the angle θ to the vertical direction. In the figure, the angular ranges of 1 ° to 5 ° and from -67 ° to -73 ° are each shown enlarged as a section.

The Simulation, which was carried out with the help of the so-called "Finite Difference Time Domain" method, illustrates the effect of the coupling structure for one from one side the coupling structure incident wave. Positive angles of the bent Radiation correspond to a diffraction in the forward direction, negative angles of a backward diffraction. This simulation became a vertical extension of the recesses of the coupling structure of 500 nm, a lateral extent of 135 nm and a period length of 270 nm at a vacuum wavelength the pump radiation of 920 nm and a refractive index of 3.4 based. The period length therefore corresponds almost to the wavelength of the pump radiation in the area the coupling structure (920 nm / 3.4). The recesses are here with Filled with air.

through The coupling structure can thus a large part of the diffracted intensity I in small Angle to the vertical direction to be deflected. In the shown Example will be a large part the radiation diffracted at an angle of less than 4 °. An optical pump of the emission range is thereby simplified.

In comparison shows 5 a corresponding simulation for a semiconductor device, in which no coupling structure is provided. In this case, predominantly scattering occurs in the forward direction. An efficient deflection of the pump radiation in the direction of the emission region into small angles to the vertical direction, for example of 20 ° or less, does not take place.

According to the simulations performed By means of the coupling structure about 38% of the pump radiation power in coupled to the emission area, while without such a coupling structure only about 11% of the pump radiation power into the emission range reach. Due to the coupling structure, the coupling can therefore on be increased more than three times as high value.

In 6 a simulation of the course of the intensity I of the deflected pump radiation is shown as a course along the lateral direction x. Starting from a central axis of the emission range, which represents the zero point of the x-axis, the integers represented in arbitrary units are intensity in both directions over a range of more than 45 μm each, which ranges between a value of 0.2 and a value of 0.35. Thus, in the lateral direction x, a comparatively uniform coupling of the pump radiation into the emission region takes place. Optical pumping of the emission range is thereby simplified.

An exemplary embodiment of a method for producing a radiation-emitting component with a vertical emission direction is shown in FIGS 7A to 7E shown by some intermediate steps shown in a schematic sectional view. The method is described here by way of example for the production of a semiconductor component, which in connection with 1 corresponds to the first embodiment described.

As in 7A is shown, the semiconductor layer sequence, which is the semiconductor body 2 forms on a growth substrate 21 deposited. This is preferably carried out epitaxially, for example by means of MBE or MOVPE.

The semiconductor layer sequence here comprises the pump region 3 and the emission area 4 as well as between the pumping area 3 and the emission area 4 arranged mirrors 5 , The pump region, the emission region and the mirror are thus monolithic in a common semiconductor body 2 integrated. Thus, the production can take place in a common epitaxy step.

The following will, as in 7B shown, material of the emission range 4 and the mirror 5 partially removed. One between the waveguide 35 and the emission area 4 arranged cladding layer 31 is exposed so. On this coat layer 31 becomes a first contact in the exposed area 61 deposited. This is preferably done by means of vapor deposition or sputtering, whereby the contact can also be designed in a multi-layered manner.

The growth substrate 21 is from the semiconductor body 2 removed with the semiconductor layer sequence. This can be done, for example, mechanically, for example by means of grinding, lapping or polishing and / or chemically, for example by wet-chemical or dry-chemical etching. Alternatively, the growth substrate can also be removed by means of coherent radiation, for example laser radiation. In this way, the on the emission area 4 opposite side of the pumping area 3 arranged cladding layer 32 be made available for structuring. The semiconductor body 2 in which the growth substrate is removed is in 7C shown.

The coupling structure 7 will, as in 7D represented by means of recesses in the semiconductor body 2 educated. The recesses 71 are preferably prepared by means of lithographic structuring and subsequent wet-chemical or dry-chemical etching. The recesses 71 may be at least partially filled with a dielectric material (not explicitly shown).

The following may apply to the emission range 4 opposite side of the pumping area 3 a second contact 62 be deposited. The deposition of the second contact can also be done for example by means of vapor deposition or sputtering.

The completed semiconductor device 1 is in 7E shown.

The The invention is not by the description based on the embodiments limited. Much more For example, the invention includes every novel feature as well as every combination of features, in particular any combination of features in the claims includes, even if this feature or this combination itself not explicitly in the claims or the embodiments is specified.

Claims (43)

Radiation-emitting semiconductor component ( 1 ) with a vertical emission direction, which has a semiconductor body ( 2 ) comprising a semiconductor layer sequence, wherein - in the semiconductor layer sequence, a pump region provided for generating a pump radiation ( 3 ) is trained; - on the pumping area ( 3 ) an emission area provided for generating emission radiation ( 4 ) is arranged; and - in the semiconductor device ( 1 ) a coupling structure ( 7 ) is trained. Semiconductor component according to Claim 1, in which the coupling structure ( 7 ) is intended to be a part of the operation in the semiconductor device ( 1 ) to redirect in a lateral direction propagating pump radiation in an oblique or perpendicular direction to the lateral direction. Semiconductor component according to Claim 1 or 2, in which the coupling structure ( 7 ) is provided for, during operation of the semiconductor device ( 1 ) propagating in the lateral direction pump radiation partly in the emission area ( 4 ). Semiconductor component according to one of the preceding claims, wherein the pump radiation in Operation of the semiconductor device ( 1 ) by means of reflection and / or diffraction at the coupling structure ( 7 ) is coupled into the emission range. Semiconductor component according to one of the preceding claims, in which the emission region ( 4 ) coupled pump radiation the emission range ( 4 ) optically pumps. Semiconductor component according to one of the preceding claims, in which the emission region ( 4 ) coupled pump radiation ( 3 ) predominantly at an angle of at most 20 ° to the vertical direction. Semiconductor component according to one of the preceding claims, in which the coupling structure ( 7 ) on the emission area ( 4 ) facing away from the pumping area ( 3 ) is arranged. Semiconductor component according to one of the preceding claims, in which the coupling structure ( 7 ) is periodically formed along the lateral direction. Semiconductor component according to one of the preceding claims, in which the coupling structure ( 7 ) is formed quasi-periodically along the lateral direction. Semiconductor component according to Claim 8 or 9, in which, for a period length L of the coupling structure ( 7 ) applies: (N - 0.4) · λ ≦ L ≦ (N + 0.4) · λ, where λ is the wavelength of the pump radiation in the region of the coupling structure ( 7 ) and N is a positive integer. A semiconductor device according to claim 10, wherein N = 1 applies. Semiconductor component according to Claim 8 or 9, in which a period length of the coupling structure ( 7 ) is between 0.8 times and 1.2 times the wavelength of the pump radiation in the region of the coupling structure. Semiconductor component according to one of the preceding claims, in which the coupling structure ( 7 ) by means of juxtaposed recesses ( 71 ) is formed. Semiconductor component according to Claim 13, in which the recesses ( 71 ) are arranged according to a random structure. Semiconductor component according to Claim 13, with reference to Claim 8 or 9, in which a lateral extent of the recesses ( 71 ) is between 0.3 times inclusive and 0.7 times the period length inclusive. Semiconductor component according to one of Claims 13 to 15, in which the recesses ( 71 ) in the semiconductor body ( 2 ) extend into it. Semiconductor component according to one of Claims 13 to 16, in which the recesses ( 71 ) are trench-like. Semiconductor component according to one of Claims 13 to 17, in which the recesses ( 71 ) vertical side edges ( 710 ) exhibit. Semiconductor component according to one of Claims 13 to 18, in which the recesses ( 71 ) are at least partially filled with a filling material. A semiconductor device according to claim 19, wherein the filling material contains a dielectric material. Semiconductor component according to one of the preceding claims, in which the coupling structure ( 7 ) is sawtooth-like along the lateral direction. Semiconductor component according to one of the preceding claims, in which the coupling structure ( 7 ) is performed in the vertical direction such that a predetermined proportion of the pump radiation in the emission area ( 4 ) is coupled. Semiconductor component according to one of the preceding claims, in which the pump region ( 3 ) in a waveguide ( 35 ), which is provided for guiding the pump radiation, is arranged. Semiconductor component according to Claim 23, in which the coupling structure ( 7 ) in the vertical direction in the waveguide ( 35 ) protrudes. Semiconductor component according to Claim 24, in which the coupling structure ( 7 ) in the vertical direction by at most 30% of the vertical extent of the waveguide ( 35 ) in the waveguide ( 35 ) protrudes. Semiconductor component according to Claim 23, in which a spacing of the coupling structure ( 7 ) from a nearest boundary of the waveguide ( 35 ) in the vertical direction is at most as large as the vertical extent of the waveguide ( 35 ). Semiconductor component according to one of the preceding claims, in which the emission region ( 4 ) monolithically into the semiconductor body ( 2 ) is integrated. Semiconductor component according to one of Claims 1 to 26, in which the emission region ( 4 ) separately from the semiconductor body ( 2 ) and on the semiconductor body ( 2 ) is attached. Semiconductor component according to one of the preceding claims, in which, between the emission region ( 4 ) and the pumping area ( 3 ) a mirror ( 5 ) is trained. Semiconductor component according to Claim 29, in which the mirror ( 5 ) has a lower reflectivity for the pump radiation than for the emission radiation. Semiconductor component according to Claim 29 or 30, in which the mirror ( 5 ) in the semiconductor body ( 2 ) is integrated. Semiconductor component according to one of the preceding claims, in which the pump region ( 3 ) and / or the emission range ( 4 ) contains a III-V compound semiconductor material. Semiconductor component according to one of the preceding claims, in which the pump region ( 3 ) and / or the emission range ( 4 ) has a quantum structure. Semiconductor component according to one of the preceding Claims, that for the operation is provided with an external resonator. Method for producing a radiation-emitting semiconductor component ( 1 ) with a vertical emission direction, in which - a semiconductor body ( 2 ) with a semiconductor layer sequence, which has a pump region (FIG. 3 ) is deposited; - an emission range intended for the generation of emission radiation ( 4 ) and the pumping area ( 4 ) are stacked on top of each other or deposited one above the other; A coupling structure ( 7 ) is formed; and the radiation-emitting semiconductor component ( 1 ) is completed. Method according to claim 35, wherein for the formation of the coupling structure ( 7 ) Material of the Semiconductor Body ( 2 ) is removed area by area. The method of claim 36, wherein the material by means of a wet chemical or a dry chemical process removed becomes. Method according to one of Claims 35 to 37, in which the semiconductor body ( 2 ) on a growth substrate ( 21 ) and the growth substrate ( 21 ) before forming the coupling structure ( 7 ) Will get removed. A method according to claim 38, wherein the growth substrate ( 21 ) is mechanically and / or chemically removed. A method according to claim 38, wherein the growth substrate ( 21 ) is removed by means of coherent radiation. Method according to one of Claims 35 to 40, in which the emission range ( 4 ) as part of the semiconductor layer sequence of the semiconductor body ( 2 ) is deposited. Method according to one of Claims 35 to 40, in which the emission range ( 4 ) is prefabricated and on the semiconductor body ( 2 ) is attached. Method according to one of Claims 35 to 42, in which a radiation-emitting semiconductor component ( 1 ) is produced according to one of claims 1 to 34.