WO2006058224A1 - Reduced power magnetoresistive random access memory elements - Google Patents
Reduced power magnetoresistive random access memory elements Download PDFInfo
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- WO2006058224A1 WO2006058224A1 PCT/US2005/042764 US2005042764W WO2006058224A1 WO 2006058224 A1 WO2006058224 A1 WO 2006058224A1 US 2005042764 W US2005042764 W US 2005042764W WO 2006058224 A1 WO2006058224 A1 WO 2006058224A1
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- G—PHYSICS
- G11—INFORMATION STORAGE
- G11C—STATIC STORES
- G11C11/00—Digital stores characterised by the use of particular electric or magnetic storage elements; Storage elements therefor
- G11C11/02—Digital stores characterised by the use of particular electric or magnetic storage elements; Storage elements therefor using magnetic elements
- G11C11/14—Digital stores characterised by the use of particular electric or magnetic storage elements; Storage elements therefor using magnetic elements using thin-film elements
- G11C11/15—Digital stores characterised by the use of particular electric or magnetic storage elements; Storage elements therefor using magnetic elements using thin-film elements using multiple magnetic layers
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- G—PHYSICS
- G11—INFORMATION STORAGE
- G11C—STATIC STORES
- G11C11/00—Digital stores characterised by the use of particular electric or magnetic storage elements; Storage elements therefor
- G11C11/02—Digital stores characterised by the use of particular electric or magnetic storage elements; Storage elements therefor using magnetic elements
- G11C11/16—Digital stores characterised by the use of particular electric or magnetic storage elements; Storage elements therefor using magnetic elements using elements in which the storage effect is based on magnetic spin effect
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- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
- H01L27/00—Devices consisting of a plurality of semiconductor or other solid-state components formed in or on a common substrate
- H01L27/02—Devices consisting of a plurality of semiconductor or other solid-state components formed in or on a common substrate including semiconductor components specially adapted for rectifying, oscillating, amplifying or switching and having at least one potential-jump barrier or surface barrier; including integrated passive circuit elements with at least one potential-jump barrier or surface barrier
- H01L27/04—Devices consisting of a plurality of semiconductor or other solid-state components formed in or on a common substrate including semiconductor components specially adapted for rectifying, oscillating, amplifying or switching and having at least one potential-jump barrier or surface barrier; including integrated passive circuit elements with at least one potential-jump barrier or surface barrier the substrate being a semiconductor body
- H01L27/10—Devices consisting of a plurality of semiconductor or other solid-state components formed in or on a common substrate including semiconductor components specially adapted for rectifying, oscillating, amplifying or switching and having at least one potential-jump barrier or surface barrier; including integrated passive circuit elements with at least one potential-jump barrier or surface barrier the substrate being a semiconductor body including a plurality of individual components in a repetitive configuration
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- H—ELECTRICITY
- H10—SEMICONDUCTOR DEVICES; ELECTRIC SOLID-STATE DEVICES NOT OTHERWISE PROVIDED FOR
- H10B—ELECTRONIC MEMORY DEVICES
- H10B61/00—Magnetic memory devices, e.g. magnetoresistive RAM [MRAM] devices
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- H—ELECTRICITY
- H10—SEMICONDUCTOR DEVICES; ELECTRIC SOLID-STATE DEVICES NOT OTHERWISE PROVIDED FOR
- H10N—ELECTRIC SOLID-STATE DEVICES NOT OTHERWISE PROVIDED FOR
- H10N50/00—Galvanomagnetic devices
- H10N50/10—Magnetoresistive devices
Definitions
- the present invention generally relates to magnetoelectronic devices, and more particularly relates to magnetoresi stive random access memory elements that require lower power for operation.
- Magnetoelectronic devices spin electronic devices, and spintronic devices are synonymous terms for devices that make use of effects predominantly caused by electron spin.
- Magnetoelectronics is used in numerous information devices, and provides non- volatile, reliable, radiation resistant, and high-density data storage and retrieval.
- the numerous magnetoelectronics information devices include, but are not limited to, Magnetoresistive Random Access Memory (MRAM), magnetic sensors, and read/write heads for disk drives.
- MRAM Magnetoresistive Random Access Memory
- a magnetoelectronic information device such as an MRAM
- Each memory element typically has a structure that includes multiple magnetic layers separated by various non-magnetic layers. Information is stored as directions of magnetization vectors in the magnetic layers. Magnetic vectors in one magnetic layer are magnetically fixed or pinned, while the magnetization direction of another magnetic layer may be free to switch between the same and opposite directions that are called "parallel” and “antiparallel” states, respectively. Corresponding to the parallel and antiparallel magnetic states, the magnetic memory element has low and high electrical resistance states, respectively.
- FIG. 1 illustrates a conventional memory element array 10 having one or more memory elements 12.
- An example of one type of magnetic memory element a magnetic tunnel junction (MTJ) element, comprises a fixed ferromagnetic layer 14 that has a magnetization direction fixed with respect to an external magnetic field and a free ferromagnetic layer 16 that has a magnetization direction that is free to rotate with the external magnetic field.
- the fixed layer and free layer are separated by an insulating tunnel barrier layer 18.
- the resistance of memory element 12 relies upon the phenomenon of spin-polarized electron tunneling through the tunnel barrier layer between the free and fixed ferromagnetic layers.
- the tunneling phenomenon is electron spin dependent, making the electrical response of the MTJ element a function of the relative orientations and spin polarization of the conduction electrons between the free and fixed ferromagnetic layer.
- the memory element array 10 includes conductors 20, also referred to as digit lines 20, extending along rows of memory elements 12 and conductors 22, also referred to as word or bit lines 22, extending along columns of the memory elements 12.
- a memory element 12 is located at a cross point of a digit line 20 and a bit line 22.
- the magnetization direction of the free layer 16 of a memory element 12 is switched by supplying currents to digit line 20 and bit line 22. The currents create magnetic fields that switch the magnetization orientation of the selected memory element from parallel to anti- parallel, or vice versa.
- FIG. 2 illustrates the fields generated by a conventional linear digit line 20 and bit line 22.
- a bit current I B 30 is defined as being positive if flowing in a positive x-direction and a digit current I D 34 is defined as being positive if flowing in a positive y-direction.
- a positive bit current I B 30 passing through bit line 22 results in a circumferential bit magnetic field, H B 32, and a positive digit current I D 34 will induce a circumferential digit magnetic field H D 36.
- the magnetic fields H B 32 and HQ 36 combine to switch the magnetic orientation of the memory element 12.
- FIG. 1 illustrates a conventional memory element array
- FIG. 2 illustrates magnetic fields generated at a memory element of a conventional memory element array
- FIG. 3 is a cross-sectional view of a memory element in accordance with an exemplary embodiment of the present invention.
- FIG. 4 is a plan view of the memory element of FIG. 3 illustrating magnetic fields generated at the memory element
- FIG. 5 is a graphical illustration of a programming window of the memory element of FIG. 3;
- FIG. 6 is a cross-sectional view of a memory element in accordance with another exemplary embodiment of the present invention.
- FIG. 7 is a graphical illustration of the relationship between an anti- ferromagnetic coupling saturation field of an anti-ferromagnetic coupling material and the thickness of the anti-ferromagnetic coupling material;
- FIG. 8 is a cross-sectional view of a memory element in accordance with a further exemplary embodiment of the present invention.
- FIG. 9 is a schematic illustration of a memory element array having memory elements, shown in phantom, in accordance with an exemplary embodiment of the present invention.
- FIG. 10 is a schematic illustration of a memory element having an elliptical shape.
- FIG. 11 is a schematic illustration of a memory element having a rectangular shape.
- FIG. 3 a simplified sectional view of an MRAM array 100 comprises a scalable magnetoresistive memory element 102.
- MRAM array 100 may consist of a number of magnetoresistive memory elements 102.
- Magnetoresistive memory element 102 is sandwiched between a bit line 122 and a digit line 120.
- Bit line 122 and digit line 120 include conductive material such that a current can be passed therethrough.
- bit line 122 is positioned on top of magnetoresistive memory element 102 and digit line 120 is positioned on the bottom of magnetoresistive memory element 102, and is directed at a 90-degree angle to bit line 122.
- bit line 122 and digit line 120 are illustrated with physical contact to memory element 102, it will be understood that the various embodiments of the present invention are not so limited and bit line 122 and/or digit line 120 may be physically separated from memory element 102.
- bit line 122 is illustrated positioned above digit line 120, it will be understood that the reverse positioning of digit line 120 and bit line 122 may be utilized.
- Magnetoresistive memory element 102 comprises a first magnetic region 104, a second magnetic region 106, and a tunnel barrier 108 disposed between first magnetic region 104 and second magnetic region 106.
- magnetic region 104 includes a synthetic anti-ferromagnetic (SAF) structure 110, a structure having an an ti -ferromagnetic coupling spacer layer 134 sandwiched between two ferromagnetic portions 130 and 132.
- second magnetic region 106 may have an SAF structure 112, which has an an ti -ferromagnetic coupling spacer layer 144 disposed between two ferromagnetic portions 140 and 142.
- SAF synthetic anti-ferromagnetic
- second magnetic region 106 may have any structure suitable for forming an operable memory element 102.
- Ferromagnetic portions 130 and 132 each have a magnetic moment vector 150 and 152, respectively, that are usually held anti-parallel by the and -ferromagnetic coupling spacer layer 134.
- Magnetic region 104 has a resultant magnetic moment vector 154 and magnetic region 106 has a resultant magnetic moment vector 156.
- Resultant magnetic moment vectors 154 and 156 are oriented along an anisotropy easy-axis in a direction that is at an angle with respect to bit line 122 and digit line 120.
- the resultant magnetic moment vectors 154 and 156 are oriented at angle in the range of about 30 degrees to about 60 degrees with respect to bit line 122 and/or digit line 120.
- the resultant magnetic moment vectors 154 and 156 are oriented at an angle of about 45 degrees from bit line 122 and digit line 120.
- magnetic region 104 is a free ferromagnetic region, meaning that resultant magnetic moment vector 154 is free to rotate in the presence of an applied magnetic field.
- Magnetic region 106 is a pinned ferromagnetic region, meaning that resultant magnetic moment vector 156 is not free to rotate in the presence of a moderate applied magnetic field and is used as the reference layer.
- the two ferromagnetic portions 130 and 132 can have different thicknesses or material to provide resultant magnetic moment 154 given by AM - M 2 - M 1 .
- the SAF structure 110 will be substantially balanced; that is, AM is less than 15 percent of the average of M 2 - Mi (otherwise simply stated as "the imbalance is less than 15 percent) and is more preferably as near to zero as can be economically fabricated in production lots.
- each succeeding layer discussed in more detail below, is deposited or otherwise formed in sequence and each memory element 102 may be defined by a particular deposition, photolithography processing, etching, etc. using any of the techniques known in the semiconductor industry.
- a magnetic field is provided to set a preferred anisotropy easy-axis (induced intrinsic anisotropy).
- FIG. 4 illustrates a simplified plan view of MRAM array 100 in accordance with an embodiment of the present invention.
- magnetoresistive memory element 102 To simplify the description of magnetoresistive memory element 102, all directions will be referenced to an x- and y-coordinate system 160 as shown. To further simplify the description, only the magnetic moment vectors of region 104 are illustrated since they will be switched. As illustrated, resultant magnetic moment vector 154 is oriented along an anisotropy easy axis 162 at an angle with respect to the bit line 122 and the digit line 120. As shown, a bit current I B 170 is defined as being positive if flowing in a positive x-direction and a digit current IQ 172 is defined as being positive if flowing in a positive y-direction.
- FIG. 5 is a graphical representation 200 of a programming region or window, in terms of magnetic field H B 174 and magnetic field H D 176, within which first magnetic region 104 may be switched reliably.
- an individual memory element is programmed by flowing current through the bit line and the digit line proximate to the individual memory element.
- Information is stored by selectively switching the magnetic moment direction of first magnetic region 104 of the individual memory element 102.
- the memory element state is programmed to a "1" or “0” depending on the previous state of the bit; that is, a "1” is switched to a "0” or a “0” to a “1". All other memory elements 102 are exposed only to fields from a single line ('/2-selected memory elements), or no lines.
- a memory element is switched reliably when the magnetic region 104 of the memory element switches deterministically between a "0” state and a "1” state upon application or withdrawal of a magnetic field.
- a memory element that switches somewhat randomly between a "0" state and a "1” state upon application or withdrawal of a magnetic field does not provide reliable or desirable switching.
- an array of memory elements 102 has a distribution of switching fields with a mean value (Hsw ⁇ and a standard deviation ⁇ sw .
- the array of memory elements 102 is required to meet a predetermined switching or programming error rate.
- the applied field produced from the currents preferably is larger than the mean switching field (Hsw) by no less than approximately N ⁇ sw , where N is a positive number large enough to ensure the actual switching error rate does not exceed the predetermined programming error rate, and is typically greater than or equal to 6 for memories whose size are about 1 Mbit or larger.
- H SAT there is a maximum saturation field H SAT that can be applied to a selected memory element to ensure reliable switching.
- the field H SAT corresponds to that field which, when applied to magnetic region 104, causes magnetic moment vector 150 and 152 to be aligned approximately parallel. Therefore, H SAT is known as the saturation field of the SAF structure in region 104 and is a measure of the anti-ferromagnetic coupling between layers 130 and 132.
- an array of memory elements 102 has a distribution of saturation fields with a mean value (H SAT ) and a standard deviation ⁇ sat . Therefore, the applied field preferably is kept less than approximately (H SAT )- N ⁇ sat or the selected memory element will not be programmed reliably.
- the region 204 of graphical representation 200 is that region where a magnetic field H applied to memory element 102 by bit current I B 170 and digit current I D 172 is greater than H SAT and first magnetic region 104 of magnetoresistive memory element 102 does not switch reliably between both the "1" and "0" states.
- the region 206 of graphical representation 200 is that region where the applied field H is less than the switching field Hsw and first magnetic region 104 of magnetoresistive memory element 102 does not switch.
- H ⁇ is the total anisotropy of first magnetic region 104 and H S AT, as described above, is the anti-ferromagnetic coupling saturation field, that is, H SAT is the maximum magnetic field at which first magnetic region 104 of magnetoresistive memory element 102 will switch reliably.
- H k may be represented by the equation:
- H k (total) H k (intrinsic) + H k (shape), where H k (intrinsic) is the intrinsic anisotropy of the material comprising magnetic region 104 and H k (shape) is the anisotropy due to the shape of magnetic region 104.
- H SAT may be represented by the equation:
- Hs A ⁇ (total) Hs A ⁇ (intrinsic) + H SA ⁇ (shape).
- Hs A ⁇ (intrinsic) is the magnetic field at which the magnetic layers of first magnetic region 104 are substantially parallel to each other when formed as continuous films and Hs A ⁇ (shape) represents the magnetostatic coupling of the magnetic layers of magnetic region 104 as a result of the shape of the magnetic region 104.
- Hsw of magnetic region 104 may be reduced or minimized.
- Hk(total) or H SAT ( total) or both may be reduced or minimized.
- H k (intrinsic), H k (shape), Hs A ⁇ (intrinsic), or Hs A ⁇ (shape), or any combination thereof, may be reduced or minimized.
- ferromagnetic portions 130 and 132 may be fabricated such that magnetic region 104 has a low H k (total) value.
- magnetic region 104 may not have an H k (total) value that is so low that magnetic region 104 and, hence, magnetoresistive memory element 102, are thermally unstable and volatile.
- Thermal instability refers to the switching of the memory state due to thermal fluctuations in the magnetic layers 130 and 132.
- H k (total) has a value of less than about 15 Oe- microns divided by region width, where the "region width" is the dimension (in microns) of the first magnetic region 104 that is orthogonal to the longitudinal axis of the first magnetic region 104 and the thickness of the first magnetic region 104.
- H k (total) has a value in the range of from about 10 Oe-microns ⁇ region width (in microns) to about 15 Oe-microns ⁇ region width (in microns).
- ferromagnetic portions 130 and 132 may be formed of one or more layers of material or materials having a low H k (intrinsic) value.
- the term low H k (intrinsic) value means an H k (intrinsic) value of less than or equal to about 10 Oe.
- Examples of materials that have a low H k (intrinsic) value that is suitable for forming ferromagnetic portions 130 and 132 of magnetic region 104 but that does not render magnetic region 104 thermally unstable include nickel (Ni), iron (Fe), cobalt (Co), or alloys of Ni, alloys of Fe, or alloys of Co, such as NiFeB, NiFeMb, NiFeTa, NiFeCo, and the like.
- Ferromagnetic portions 130 and 132 may be formed of the same material or may be formed of different materials having a low H k (intrinsic) value.
- magnetic region 104 may be fabricated utilizing a material or materials that produce a low H k (shape) value to form ferromagnetic portions 130 and 132. Again, however, it is preferred that the material that forms magnetic region 104 may not produce an H k (total) value that is so low that magnetic region 104 and, hence, magnetoresi stive memory element 102, are thermally unstable and volatile. As discussed above, materials producing a low H k (shape) value for a given memory element shape include materials having a low saturation magnetization Ms.
- low saturation magnetization refers to those materials having a magnetization that is less than or equal to the magnetization of Ni 80 Fe 20 .
- Ni 80 Fe 20 has a magnetization approximately equal to 800 kA/m and a saturation flux density of approximately 1 Tesla.
- the use of a low magnetization material(s) for ferromagnetic portions 130 and 132 also serves to reduce or minimize HsA ⁇ (shape).
- Low magnetization materials suitable for forming ferromagnetic portions 130 and 132 comprise Ni 80 Fe 20 and alloys of Ni, alloys of Fe, or alloys of Co, such as, for example, NiFeB, NiFeMb, NiFeTa, and NiFeCo. Again, ferromagnetic po ⁇ ions 130 and 132 may be formed of the same or different low magnetization materials.
- Ni 80 Fe 20 with materials such as molybdenum, tantalum, boron, and the like also may result in a material with a low Hk(intrinsic) value and a magnetization less than those of Ni 80 Fe 2O , thus facilitating fabrication of a low power memory element 102.
- doping with such materials also may decrease the magnetoresi stance through tunnel barrier 108, and thus decrease the performance of memory element 102.
- the spin polarization of the tunneling electrons determines the magnetoresi stance
- low magnetization materials typically also have low spin polarization. Accordingly, in one alternative embodiment of the invention, as illustrated in FIG.
- a magnetoresi stive memory element 250 may have a ferromagnetic portion 132 that comprises two materials, a first material 252 with a low magnetization that reduces the value of H k (shape) of magnetic region 104 and a second material 254, disposed close to the tunnel barrier 108, with a high polarization that compensates for the decrease in the magnetoresistance due to the first material 252.
- the term "high polarization material” is any material having a spin polarization that is greater than or equal to Ni 80 Fe 20 .
- Second material 254 may comprise material such as, for example, Co, Fe, and CoFe and may also comprise Ni 80 Fe 20 when the first material 252 has a magnetization lower than Ni 80 Fe 20 .
- first material 252 and/or second material 254 comprise materials that also have a low H k (intrinsic), as described above.
- first magnetic region 104 is preferably a moment- balanced SAF structure
- ferromagnetic portion 130 has a thickness such that the magnetic moments of ferromagnetic portions 132 and 130 have the same magnitude.
- ferromagnetic portion 130 also comprises first material 252 and second material 254.
- the Hk(shape) of a single magnetic layer is approximately proportional to N 11 x M s xt /w where N d is a demagnetizing factor that increases with aspect ratio, t is the thickness of the layer, and w is the region width.
- N d is a demagnetizing factor that increases with aspect ratio
- t is the thickness of the layer
- w is the region width.
- This formula also applies for the layers in the SAF structure of first magnetic region 104.
- the SAF structure of first magnetic region 104 does reduce Hk(shape) compared to a single film of comparable thickness 2xt, the Hk(shape) is still finite due to asymmetry in the switching process.
- the magnetic layers are not perfectly antiparallel during switching, so that each layer's magnetostatic fields (that produce Hk(shape)) do not perfectly cancel one another.
- magnetic region 104 may be fabricated with the minimum possible thickness t for ferromagnetic layers 130 and 132. As discussed above, a thinner thickness t will result in a smaller Hk(shape) and Hs A ⁇ (shape) since the magnetostatic fields that produce Hk(shape) and HsA ⁇ (shape) are proportional to thickness. The minimum thickness possible is limited by the requirement of thermal stability. Note that by reducing t, both Hk(shape) and total volume V of layers 130 and 132 are reduced for the bit, so that the energy barrier is reduced by approximately t .
- first magnetic region 104 also may be fabricated to have a low H k (shape) value by forming it in a shape having a low aspect ratio.
- first magnetic region 104 has a length preferably measured along a long axis of region 104, and a width measured orthogonal to the length, and a length/width ratio in a range of about 1 to about 3 for a non-circular plan.
- a memory element 400 which may be the same as memory element 102, may have a first magnetic region 104 of an elliptical shape with a length 402 and width 404 and with a length/width ratio of about 1 to about 3.
- FIG. 10 in one embodiment of the invention, may have a first magnetic region 104 of an elliptical shape with a length 402 and width 404 and with a length/width ratio of about 1 to about 3.
- a memory element 410 which may be the same as memory element 102, may have a first magnetic region 104 of a rectangular shape with a length 412 and width 414 and having a length/width ratio of about 1 to about 3.
- the first magnetic region 104 of a memory element may be circular in shape (length/width ratio of 1) to minimize the contribution to the switching field from shape anisotropy H k (shape) and also because it is easier to use photolithographic processing to scale the device to smaller dimensions laterally.
- first magnetic region 104 can have any other suitable shape, such as square or diamond.
- first magnetic region 104 has a length/width ratio in a range of about 2 to about 2.5.
- magnetic region 104 may be fabricated to reduce or minimize Hs A ⁇ (total) to reduce the power requirements of memory element 102. Again, however, as discussed above with reference to FIG. 5, magnetic region 104 may not have an HsA ⁇ (total) value that is so low that there is no operable programming window. In other words, while Hs A ⁇ (total) may be reduced or minimized, its value preferably is such that the programming window operable for switching magnetic region 104 can be defined as above by the equation H wm ⁇ ((H SAT )-
- Hs A ⁇ (total) has a value in the range of from about 150 Oe to about 350 Oe. In a preferred embodiment, Hs A ⁇ (total) has a value less than or equal to approximately 180/w 05 (Oe), where w is the region width of magnetic region 104, as previously described. [0043] At present memory element dimensions in the range of 0.5 to 1 micron, the dominant contribution to Hs A ⁇ (total) is from Hs A ⁇ (intrinsic).
- Hs A ⁇ (intrinsic) is determined by the anti-ferromagnetic coupling material that comprise anti -ferromagnetic coupling spacer layer 134 and its thickness.
- anti-ferromagnetic coupling spacer layer 134 comprises one of the elements ruthenium, osmium, rhenium, chromium, rhodium, copper, or combinations thereof.
- anti-ferromagnetic coupling spacer layer 134 comprises ruthenium.
- Hs A ⁇ (intrinsic), and hence Hs A ⁇ (total) may be reduced or minimized by fabricating anti-ferromagnetic coupling spacer layer 134 with a thickness such that magnetic region 104 comprises a second order SAF.
- FIG. 7 is a graph that illustrates a typical relationship between the value of Hs A ⁇ (intrinsic) and the thickness of an anti -ferromagnetic coupling material, such as ruthenium, that may be used to form anti-ferromagnetic coupling spacer layer 134.
- the anti -ferromagnetic coupling material operates as an anti- ferromagnetic coupling spacer layer 134 at a first peak or first range of thicknesses 280.
- first peak 280 the anti -ferromagnetic coupling spacer layer 134 forms a first order SAF with ferromagnetic layers 130 and 132 of FIG. 3.
- the anti-ferromagnetic coupling material also may operate as an anti-ferromagnetic coupling spacer layer 134 at a second peak or range of thicknesses 282, thus forming a second order SAF with ferromagnetic layers 130 and 132. As illustrated in FIG. 7, the values of HsA ⁇ (intrinsic) are relatively higher at the first peak 280 than at the second peak 282.
- magnetic region 104 as a second order SAF, that is, with an anti-ferromagnetic coupling spacer layer 134 having a thickness within the range of thicknesses of the second peak 282
- Hs A ⁇ (total) may be reduced or minimized, thus reducing or minimizing Hsw-
- the second peak is much flatter as a function of spacer layer thickness compared to the first order peak, so that the spacer layer thickness can vary over a wider range and still supply an Hs A ⁇ (intrinsic) of nominally the same magnitude.
- HSAT insensitivity to spacer layer thickness may be desirable for robust and reproducible manufacturing.
- HsA ⁇ (total) preferably is large enough that there exists an operable programming window for programming memory element 102.
- Hs A ⁇ (total) may be too low to provide a satisfactory programming window for memory element 102.
- a magnetoresistive memory element 300 may comprise a first interface layer 302 disposed at a first surface of anti-ferromagnetic coupling spacer layer 134 and/or a second interface layer 304 disposed at a second surface of anti-ferromagnetic coupling spacer layer 134.
- magnetic region 104 may be fabricated as a first order SAF, that is, with an anti-ferromagnetic coupling spacer layer 134 having a thickness within the range of thicknesses of the first peak 280.
- anti-ferromagnetic coupling spacer layer 134 has a thickness that is larger than a thickness t max that results in a maximum Hs A ⁇ (intrinsic).
- Hs A ⁇ (intrinsic) may be optimized along first peak 280 to reduce the power requirements of memory element 102 but also to provide a suitable programming window within which memory element 102 may be switched.
- HsA ⁇ (intrinsic) when magnetic region 104 is fabricated as a first order SAF, HsA ⁇ (intrinsic) may be further optimized by utilizing interface layers 302 and/or 304, as illustrated in FIG. 8.
- interface layers 302 and/or 304 it may be desirable to fabricate magnetic region 104 with an an ti -ferromagnetic coupling spacer layer thickness that exhibits an HsA ⁇ (intrinsic) that is approximately equal to or below a predetermined Hs A ⁇ (intrinsic).
- Hs A ⁇ (intrinsic) may be below a desired Hs A ⁇ (intrinsic).
- interface layers 302 and/or 304 may be utilized to increase the HsA ⁇ (intrinsic) to the desired value.
- Hsw also may be reduced or minimized, thus reducing the power requirements of memory element 102, by reducing or minimizing Hs A ⁇ (shape).
- Hs A ⁇ (shape) may be reduced or minimized by fabricating magnetic layers 130 and 132 from a low magnetization material. Also as described above, in another embodiment of the present invention, Hs A ⁇ (shape) may be reduced or minimized by fabricating magnetic layers 130 and 132 with a minimum thickness t.
- Hs A ⁇ (shape) also may be reduced by fabricating memory element 102 with a shape having one or more substantially sharp or pointed ends along the anisotropy axis that exhibit magnetostatic coupling of ferromagnetic layers 130 and 132 that is lower than the magnetostatic coupling of layers 130 and 132 of a memory element 102 having a shape with substantially rounded ends, such as a circular-shaped memory element 102.
- memory element 102 may be formed in the shape of an ellipse that comprises substantially sharp or pointed ends 320 along a longitudinal axis 322 of the memory element.
- a memory element 102 having this shape will exhibit less magnetostatic coupling, and hence a lower Hs A ⁇ (shape) value, than a comparable memory element 102 having a circular shape or an elliptical shape with substantially rounded ends. It will be appreciated, however, that memory element 102 may be fabricated with a variety of other shapes, such as a diamond shape, that will exhibit reduced magnetostatic coupling and hence a reduced or minimized H S A ⁇ (shape). [0048] Accordingly, magnetoresistive random access memory elements that require lower power for programming in accordance with the present invention have been described.
- the power requirements for programming the memory elements are related to the magnetic switching field Hsw represented by the equation H sw ⁇
- the embodiments of the present invention provide methods and structures for reducing and/or minimizing H k and H SAT - While at least one exemplary embodiment has been presented in the foregoing detailed description of the invention, it should be appreciated that a vast number of variations exist. It should also be appreciated that the exemplary embodiment or exemplary embodiments are only examples, and are not intended to limit the scope, applicability, or configuration of the invention in any way.
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KR1020077011707A KR101247255B1 (en) | 2004-11-24 | 2005-11-21 | Reduced power magnetoresistive random access memory elements |
JP2007543529A JP5080267B2 (en) | 2004-11-24 | 2005-11-21 | Magnetoresistive random access device having an array of memory elements and method of manufacturing magnetoelectronic memory elements |
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US10/997,118 US7129098B2 (en) | 2004-11-24 | 2004-11-24 | Reduced power magnetoresistive random access memory elements |
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Families Citing this family (23)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US7502248B2 (en) * | 2004-05-21 | 2009-03-10 | Samsung Electronics Co., Ltd. | Multi-bit magnetic random access memory device |
US7424663B2 (en) * | 2005-01-19 | 2008-09-09 | Intel Corporation | Lowering voltage for cache memory operation |
KR100626390B1 (en) * | 2005-02-07 | 2006-09-20 | 삼성전자주식회사 | Magnetic random access memory devices and methods of forming the same |
JP2006332527A (en) * | 2005-05-30 | 2006-12-07 | Renesas Technology Corp | Magnetic storage element |
US7903452B2 (en) * | 2006-06-23 | 2011-03-08 | Qimonda Ag | Magnetoresistive memory cell |
JP4682998B2 (en) * | 2007-03-15 | 2011-05-11 | ソニー株式会社 | Memory element and memory |
TWI333208B (en) * | 2007-03-26 | 2010-11-11 | Ind Tech Res Inst | Magnetic memory and method for manufacturing the same |
US7969011B2 (en) * | 2008-09-29 | 2011-06-28 | Sandisk 3D Llc | MIIM diodes having stacked structure |
US20100078758A1 (en) * | 2008-09-29 | 2010-04-01 | Sekar Deepak C | Miim diodes |
US7615439B1 (en) * | 2008-09-29 | 2009-11-10 | Sandisk Corporation | Damascene process for carbon memory element with MIIM diode |
US7880209B2 (en) * | 2008-10-09 | 2011-02-01 | Seagate Technology Llc | MRAM cells including coupled free ferromagnetic layers for stabilization |
US7897453B2 (en) * | 2008-12-16 | 2011-03-01 | Sandisk 3D Llc | Dual insulating layer diode with asymmetric interface state and method of fabrication |
US7869267B2 (en) * | 2008-12-29 | 2011-01-11 | Numonyx B.V. | Method for low power accessing a phase change memory device |
US7833806B2 (en) * | 2009-01-30 | 2010-11-16 | Everspin Technologies, Inc. | Structure and method for fabricating cladded conductive lines in magnetic memories |
US8519495B2 (en) * | 2009-02-17 | 2013-08-27 | Seagate Technology Llc | Single line MRAM |
US8533853B2 (en) | 2009-06-12 | 2013-09-10 | Telecommunication Systems, Inc. | Location sensitive solid state drive |
JPWO2011065323A1 (en) * | 2009-11-27 | 2013-04-11 | 日本電気株式会社 | Magnetoresistive element and magnetic random access memory |
US8558331B2 (en) * | 2009-12-08 | 2013-10-15 | Qualcomm Incorporated | Magnetic tunnel junction device |
US8399941B2 (en) * | 2010-11-05 | 2013-03-19 | Grandis, Inc. | Magnetic junction elements having an easy cone anisotropy and a magnetic memory using such magnetic junction elements |
CN102074266A (en) * | 2010-12-17 | 2011-05-25 | 电子科技大学 | Spin valve storage cell for stabilizing residual magnetism state |
KR101441201B1 (en) * | 2012-12-17 | 2014-09-18 | 인하대학교 산학협력단 | Spin Transfer Torque Magnetic Random Access Memory And Fabircation Method Of The Same |
CN103956249B (en) * | 2014-04-03 | 2017-06-30 | 中国科学院物理研究所 | A kind of artificial antiferromagnetic coupling multi-layer film material of perpendicular magnetic anisotropy |
WO2018125634A1 (en) * | 2016-12-27 | 2018-07-05 | Everspin Technologies, Inc. | Data storage in synthetic antiferromagnets included in magnetic tunnel junctions |
Citations (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US6531723B1 (en) * | 2001-10-16 | 2003-03-11 | Motorola, Inc. | Magnetoresistance random access memory for improved scalability |
US6545906B1 (en) * | 2001-10-16 | 2003-04-08 | Motorola, Inc. | Method of writing to scalable magnetoresistance random access memory element |
Family Cites Families (172)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US3163853A (en) | 1958-02-20 | 1964-12-29 | Sperry Rand Corp | Magnetic storage thin film |
US3448438A (en) | 1965-03-19 | 1969-06-03 | Hughes Aircraft Co | Thin film nondestructive memory |
US3573760A (en) * | 1968-12-16 | 1971-04-06 | Ibm | High density thin film memory and method of operation |
US3638199A (en) * | 1969-12-19 | 1972-01-25 | Ibm | Data-processing system with a storage having a plurality of simultaneously accessible locations |
US3707706A (en) | 1970-11-04 | 1972-12-26 | Honeywell Inf Systems | Multiple state memory |
US3913080A (en) | 1973-04-16 | 1975-10-14 | Electronic Memories & Magnetic | Multi-bit core storage |
US4103315A (en) | 1977-06-24 | 1978-07-25 | International Business Machines Corporation | Antiferromagnetic-ferromagnetic exchange bias films |
US4356523A (en) | 1980-06-09 | 1982-10-26 | Ampex Corporation | Narrow track magnetoresistive transducer assembly |
US4351712A (en) | 1980-12-10 | 1982-09-28 | International Business Machines Corporation | Low energy ion beam oxidation process |
JPS5845619A (en) | 1981-09-09 | 1983-03-16 | Hitachi Ltd | Magneto-resistance effect type thin film magnetic head |
US4719568A (en) * | 1982-12-30 | 1988-01-12 | International Business Machines Corporation | Hierarchical memory system including separate cache memories for storing data and instructions |
US4455626A (en) | 1983-03-21 | 1984-06-19 | Honeywell Inc. | Thin film memory with magnetoresistive read-out |
US4663685A (en) * | 1985-08-15 | 1987-05-05 | International Business Machines | Magnetoresistive read transducer having patterned longitudinal bias |
US4780848A (en) | 1986-06-03 | 1988-10-25 | Honeywell Inc. | Magnetoresistive memory with multi-layer storage cells having layers of limited thickness |
US4731757A (en) * | 1986-06-27 | 1988-03-15 | Honeywell Inc. | Magnetoresistive memory including thin film storage cells having tapered ends |
US4751677A (en) | 1986-09-16 | 1988-06-14 | Honeywell Inc. | Differential arrangement magnetic memory cell |
US4754431A (en) | 1987-01-28 | 1988-06-28 | Honeywell Inc. | Vialess shorting bars for magnetoresistive devices |
US4825325A (en) * | 1987-10-30 | 1989-04-25 | International Business Machines Corporation | Magnetoresistive read transducer assembly |
US4884235A (en) | 1988-07-19 | 1989-11-28 | Thiele Alfred A | Micromagnetic memory package |
US5039655A (en) | 1989-07-28 | 1991-08-13 | Ampex Corporation | Thin film memory device having superconductor keeper for eliminating magnetic domain creep |
US5075247A (en) | 1990-01-18 | 1991-12-24 | Microunity Systems Engineering, Inc. | Method of making hall effect semiconductor memory cell |
US5173873A (en) | 1990-06-28 | 1992-12-22 | The United States Of America As Represented By The Administrator Of The National Aeronautics And Space Administration | High speed magneto-resistive random access memory |
JP3483895B2 (en) | 1990-11-01 | 2004-01-06 | 株式会社東芝 | Magnetoresistive film |
JP2601022B2 (en) * | 1990-11-30 | 1997-04-16 | 日本電気株式会社 | Method for manufacturing semiconductor device |
US5159513A (en) | 1991-02-08 | 1992-10-27 | International Business Machines Corporation | Magnetoresistive sensor based on the spin valve effect |
US5284701A (en) * | 1991-02-11 | 1994-02-08 | Ashland Oil, Inc. | Carbon fiber reinforced coatings |
CA2060835A1 (en) | 1991-02-11 | 1992-08-12 | Romney R. Katti | Integrated, non-volatile, high-speed analog random access memory |
DE69225920T2 (en) | 1991-03-06 | 1998-10-15 | Mitsubishi Electric Corp | Magnetic thin film memory device |
KR930008856B1 (en) | 1991-05-15 | 1993-09-16 | 금성일렉트론 주식회사 | Mixing apparatus for constant ratio of chemical source |
JP3065736B2 (en) | 1991-10-01 | 2000-07-17 | 松下電器産業株式会社 | Semiconductor storage device |
US5258884A (en) | 1991-10-17 | 1993-11-02 | International Business Machines Corporation | Magnetoresistive read transducer containing a titanium and tungsten alloy spacer layer |
US5178074A (en) * | 1991-11-21 | 1993-01-12 | Trinity Industries, Inc. | Railway gondola car |
US5268806A (en) | 1992-01-21 | 1993-12-07 | International Business Machines Corporation | Magnetoresistive transducer having tantalum lead conductors |
US5285339A (en) * | 1992-02-28 | 1994-02-08 | International Business Machines Corporation | Magnetoresistive read transducer having improved bias profile |
US5398200A (en) * | 1992-03-02 | 1995-03-14 | Motorola, Inc. | Vertically formed semiconductor random access memory device |
US5347485A (en) | 1992-03-03 | 1994-09-13 | Mitsubishi Denki Kabushiki Kaisha | Magnetic thin film memory |
US5329486A (en) | 1992-04-24 | 1994-07-12 | Motorola, Inc. | Ferromagnetic memory device |
US5448515A (en) | 1992-09-02 | 1995-09-05 | Mitsubishi Denki Kabushiki Kaisha | Magnetic thin film memory and recording/reproduction method therefor |
US5420819A (en) * | 1992-09-24 | 1995-05-30 | Nonvolatile Electronics, Incorporated | Method for sensing data in a magnetoresistive memory using large fractions of memory cell films for data storage |
US5617071A (en) * | 1992-11-16 | 1997-04-01 | Nonvolatile Electronics, Incorporated | Magnetoresistive structure comprising ferromagnetic thin films and intermediate alloy layer having magnetic concentrator and shielding permeable masses |
US5301079A (en) * | 1992-11-17 | 1994-04-05 | International Business Machines Corporation | Current biased magnetoresistive spin valve sensor |
US5348894A (en) | 1993-01-27 | 1994-09-20 | Texas Instruments Incorporated | Method of forming electrical connections to high dielectric constant materials |
US5343422A (en) | 1993-02-23 | 1994-08-30 | International Business Machines Corporation | Nonvolatile magnetoresistive storage device using spin valve effect |
US5396455A (en) * | 1993-04-30 | 1995-03-07 | International Business Machines Corporation | Magnetic non-volatile random access memory |
JP3179937B2 (en) | 1993-05-01 | 2001-06-25 | 株式会社東芝 | Semiconductor device |
US5349302A (en) | 1993-05-13 | 1994-09-20 | Honeywell Inc. | Sense amplifier input stage for single array memory |
JPH0766033A (en) | 1993-08-30 | 1995-03-10 | Mitsubishi Electric Corp | Magnetoresistance element, and magnetic thin film memory and magnetoresistance sensor using the magnetoresistance element |
JP3223480B2 (en) | 1993-09-10 | 2001-10-29 | 本田技研工業株式会社 | Evaporative fuel processor for internal combustion engines |
US5477482A (en) | 1993-10-01 | 1995-12-19 | The United States Of America As Represented By The Secretary Of The Navy | Ultra high density, non-volatile ferromagnetic random access memory |
US5408377A (en) * | 1993-10-15 | 1995-04-18 | International Business Machines Corporation | Magnetoresistive sensor with improved ferromagnetic sensing layer and magnetic recording system using the sensor |
US5832534A (en) | 1994-01-04 | 1998-11-03 | Intel Corporation | Method and apparatus for maintaining cache coherency using a single controller for multiple cache memories |
US5442508A (en) | 1994-05-25 | 1995-08-15 | Eastman Kodak Company | Giant magnetoresistive reproduce head having dual magnetoresistive sensor |
US5528440A (en) | 1994-07-26 | 1996-06-18 | International Business Machines Corporation | Spin valve magnetoresistive element with longitudinal exchange biasing of end regions abutting the free layer, and magnetic recording system using the element |
US5452243A (en) | 1994-07-27 | 1995-09-19 | Cypress Semiconductor Corporation | Fully static CAM cells with low write power and methods of matching and writing to the same |
EP0731969B1 (en) | 1994-10-05 | 1999-12-01 | Koninklijke Philips Electronics N.V. | Magnetic multilayer device including a resonant-tunneling double-barrier structure |
US5567523A (en) | 1994-10-19 | 1996-10-22 | Kobe Steel Research Laboratories, Usa, Applied Electronics Center | Magnetic recording medium comprising a carbon substrate, a silicon or aluminum nitride sub layer, and a barium hexaferrite magnetic layer |
JP3714696B2 (en) | 1994-10-21 | 2005-11-09 | 富士通株式会社 | Semiconductor memory device |
US6189077B1 (en) * | 1994-12-15 | 2001-02-13 | Texas Instruments Incorporated | Two computer access circuit using address translation into common register file |
US5496759A (en) * | 1994-12-29 | 1996-03-05 | Honeywell Inc. | Highly producible magnetoresistive RAM process |
US5534793A (en) | 1995-01-24 | 1996-07-09 | Texas Instruments Incorporated | Parallel antifuse routing scheme (PARS) circuit and method for field programmable gate arrays |
US5587943A (en) | 1995-02-13 | 1996-12-24 | Integrated Microtransducer Electronics Corporation | Nonvolatile magnetoresistive memory with fully closed flux operation |
US5541868A (en) | 1995-02-21 | 1996-07-30 | The United States Of America As Represented By The Secretary Of The Navy | Annular GMR-based memory element |
JPH08287422A (en) | 1995-04-07 | 1996-11-01 | Alps Electric Co Ltd | Magnetoresistance effect head |
US6169687B1 (en) * | 1995-04-21 | 2001-01-02 | Mark B. Johnson | High density and speed magneto-electronic memory for use in computing system |
US5585986A (en) | 1995-05-15 | 1996-12-17 | International Business Machines Corporation | Digital magnetoresistive sensor based on the giant magnetoresistance effect |
JP2778626B2 (en) | 1995-06-02 | 1998-07-23 | 日本電気株式会社 | Magnetoresistance effect film, method of manufacturing the same, and magnetoresistance effect element |
US5702831A (en) | 1995-11-06 | 1997-12-30 | Motorola | Ferromagnetic GMR material |
JP3767930B2 (en) | 1995-11-13 | 2006-04-19 | 沖電気工業株式会社 | Information recording / reproducing method and information storage device |
US5659499A (en) | 1995-11-24 | 1997-08-19 | Motorola | Magnetic memory and method therefor |
US5828578A (en) | 1995-11-29 | 1998-10-27 | S3 Incorporated | Microprocessor with a large cache shared by redundant CPUs for increasing manufacturing yield |
JP3293437B2 (en) * | 1995-12-19 | 2002-06-17 | 松下電器産業株式会社 | Magnetoresistive element, magnetoresistive head and memory element |
US5569617A (en) | 1995-12-21 | 1996-10-29 | Honeywell Inc. | Method of making integrated spacer for magnetoresistive RAM |
US5712612A (en) * | 1996-01-02 | 1998-01-27 | Hewlett-Packard Company | Tunneling ferrimagnetic magnetoresistive sensor |
US5909345A (en) * | 1996-02-22 | 1999-06-01 | Matsushita Electric Industrial Co., Ltd. | Magnetoresistive device and magnetoresistive head |
US5635765A (en) * | 1996-02-26 | 1997-06-03 | Cypress Semiconductor Corporation | Multi-layer gate structure |
US5650958A (en) | 1996-03-18 | 1997-07-22 | International Business Machines Corporation | Magnetic tunnel junctions with controlled magnetic response |
US5640343A (en) | 1996-03-18 | 1997-06-17 | International Business Machines Corporation | Magnetic memory array using magnetic tunnel junction devices in the memory cells |
US5764567A (en) | 1996-11-27 | 1998-06-09 | International Business Machines Corporation | Magnetic tunnel junction device with nonferromagnetic interface layer for improved magnetic field response |
US5835314A (en) | 1996-04-17 | 1998-11-10 | Massachusetts Institute Of Technology | Tunnel junction device for storage and switching of signals |
JP3076244B2 (en) | 1996-06-04 | 2000-08-14 | 日本電気株式会社 | Polishing method of multilayer wiring |
US5732016A (en) * | 1996-07-02 | 1998-03-24 | Motorola | Memory cell structure in a magnetic random access memory and a method for fabricating thereof |
US5905996A (en) * | 1996-07-29 | 1999-05-18 | Micron Technology, Inc. | Combined cache tag and data memory architecture |
US5745408A (en) * | 1996-09-09 | 1998-04-28 | Motorola, Inc. | Multi-layer magnetic memory cell with low switching current |
US5734605A (en) * | 1996-09-10 | 1998-03-31 | Motorola, Inc. | Multi-layer magnetic tunneling junction memory cells |
US5894447A (en) * | 1996-09-26 | 1999-04-13 | Kabushiki Kaisha Toshiba | Semiconductor memory device including a particular memory cell block structure |
US5861328A (en) * | 1996-10-07 | 1999-01-19 | Motorola, Inc. | Method of fabricating GMR devices |
US5699293A (en) | 1996-10-09 | 1997-12-16 | Motorola | Method of operating a random access memory device having a plurality of pairs of memory cells as the memory device |
US5835406A (en) * | 1996-10-24 | 1998-11-10 | Micron Quantum Devices, Inc. | Apparatus and method for selecting data bits read from a multistate memory |
US5757056A (en) * | 1996-11-12 | 1998-05-26 | University Of Delaware | Multiple magnetic tunnel structures |
US5801984A (en) | 1996-11-27 | 1998-09-01 | International Business Machines Corporation | Magnetic tunnel junction device with ferromagnetic multilayer having fixed magnetic moment |
US5729410A (en) * | 1996-11-27 | 1998-03-17 | International Business Machines Corporation | Magnetic tunnel junction device with longitudinal biasing |
US5748519A (en) * | 1996-12-13 | 1998-05-05 | Motorola, Inc. | Method of selecting a memory cell in a magnetic random access memory device |
US5761110A (en) | 1996-12-23 | 1998-06-02 | Lsi Logic Corporation | Memory cell capable of storing more than two logic states by using programmable resistances |
JP3325478B2 (en) * | 1996-12-27 | 2002-09-17 | ワイケイケイ株式会社 | Magnetoresistive element, magnetic detector and method of using the same |
US5902690A (en) * | 1997-02-25 | 1999-05-11 | Motorola, Inc. | Stray magnetic shielding for a non-volatile MRAM |
US5804485A (en) | 1997-02-25 | 1998-09-08 | Miracle Technology Co Ltd | High density metal gate MOS fabrication process |
US5768181A (en) | 1997-04-07 | 1998-06-16 | Motorola, Inc. | Magnetic device having multi-layer with insulating and conductive layers |
US5898612A (en) * | 1997-05-22 | 1999-04-27 | Motorola, Inc. | Magnetic memory cell with increased GMR ratio |
US5774394A (en) | 1997-05-22 | 1998-06-30 | Motorola, Inc. | Magnetic memory cell with increased GMR ratio |
US5856008A (en) * | 1997-06-05 | 1999-01-05 | Lucent Technologies Inc. | Article comprising magnetoresistive material |
US5838608A (en) | 1997-06-16 | 1998-11-17 | Motorola, Inc. | Multi-layer magnetic random access memory and method for fabricating thereof |
US5804250A (en) | 1997-07-28 | 1998-09-08 | Eastman Kodak Company | Method for fabricating stable magnetoresistive sensors |
JPH1168192A (en) * | 1997-08-18 | 1999-03-09 | Hitachi Ltd | Multi-tunnel junction, tunnel magnetoresistance effect element, magnetic sensor and magnetic recording sensor head |
DE19744095A1 (en) * | 1997-10-06 | 1999-04-15 | Siemens Ag | Memory cell array has stacked layer magnetoresistive effect layer memory elements |
US5831920A (en) | 1997-10-14 | 1998-11-03 | Motorola, Inc. | GMR device having a sense amplifier protected by a circuit for dissipating electric charges |
JPH11134620A (en) * | 1997-10-30 | 1999-05-21 | Nec Corp | Ferromagnetic tunnel junction element sensor and its manufacture |
US6188549B1 (en) * | 1997-12-10 | 2001-02-13 | Read-Rite Corporation | Magnetoresistive read/write head with high-performance gap layers |
US6048739A (en) * | 1997-12-18 | 2000-04-11 | Honeywell Inc. | Method of manufacturing a high density magnetic memory device |
US5852574A (en) | 1997-12-24 | 1998-12-22 | Motorola, Inc. | High density magnetoresistive random access memory device and operating method thereof |
US6180444B1 (en) * | 1998-02-18 | 2001-01-30 | International Business Machines Corporation | Semiconductor device having ultra-sharp P-N junction and method of manufacturing the same |
US6069820A (en) * | 1998-02-20 | 2000-05-30 | Kabushiki Kaisha Toshiba | Spin dependent conduction device |
US6738236B1 (en) * | 1998-05-07 | 2004-05-18 | Seagate Technology Llc | Spin valve/GMR sensor using synthetic antiferromagnetic layer pinned by Mn-alloy having a high blocking temperature |
EP0973169B1 (en) * | 1998-05-13 | 2005-01-26 | Sony Corporation | Element exploiting magnetic material and addressing method therefor |
US6055179A (en) * | 1998-05-19 | 2000-04-25 | Canon Kk | Memory device utilizing giant magnetoresistance effect |
US6175475B1 (en) * | 1998-05-27 | 2001-01-16 | International Business Machines Corporation | Fully-pinned, flux-closed spin valve |
DE19823826A1 (en) * | 1998-05-28 | 1999-12-02 | Burkhard Hillebrands | MRAM memory and method for reading / writing digital information into such a memory |
US6023395A (en) * | 1998-05-29 | 2000-02-08 | International Business Machines Corporation | Magnetic tunnel junction magnetoresistive sensor with in-stack biasing |
JP3234814B2 (en) * | 1998-06-30 | 2001-12-04 | 株式会社東芝 | Magnetoresistive element, magnetic head, magnetic head assembly, and magnetic recording device |
KR100620155B1 (en) * | 1998-07-15 | 2006-09-04 | 인피니언 테크놀로지스 아게 | Storage cell system in which an electric resistance of a storage element represents an information unit and can be influenced by a magnetic field, and method for producing same |
US6195240B1 (en) * | 1998-07-31 | 2001-02-27 | International Business Machines Corporation | Spin valve head with diffusion barrier |
US6072717A (en) * | 1998-09-04 | 2000-06-06 | Hewlett Packard | Stabilized magnetic memory cell |
US6172903B1 (en) * | 1998-09-22 | 2001-01-09 | Canon Kabushiki Kaisha | Hybrid device, memory apparatus using such hybrid devices and information reading method |
TW440835B (en) * | 1998-09-30 | 2001-06-16 | Siemens Ag | Magnetoresistive memory with raised interference security |
US6016269A (en) * | 1998-09-30 | 2000-01-18 | Motorola, Inc. | Quantum random address memory with magnetic readout and/or nano-memory elements |
US6055178A (en) * | 1998-12-18 | 2000-04-25 | Motorola, Inc. | Magnetic random access memory with a reference memory array |
US6175515B1 (en) * | 1998-12-31 | 2001-01-16 | Honeywell International Inc. | Vertically integrated magnetic memory |
US6191972B1 (en) * | 1999-04-30 | 2001-02-20 | Nec Corporation | Magnetic random access memory circuit |
JP3589346B2 (en) * | 1999-06-17 | 2004-11-17 | 松下電器産業株式会社 | Magnetoresistance effect element and magnetoresistance effect storage element |
JP3592140B2 (en) * | 1999-07-02 | 2004-11-24 | Tdk株式会社 | Tunnel magnetoresistive head |
US6343032B1 (en) * | 1999-07-07 | 2002-01-29 | Iowa State University Research Foundation, Inc. | Non-volatile spin dependent tunnel junction circuit |
US6383574B1 (en) * | 1999-07-23 | 2002-05-07 | Headway Technologies, Inc. | Ion implantation method for fabricating magnetoresistive (MR) sensor element |
US6052302A (en) * | 1999-09-27 | 2000-04-18 | Motorola, Inc. | Bit-wise conditional write method and system for an MRAM |
US6205052B1 (en) * | 1999-10-21 | 2001-03-20 | Motorola, Inc. | Magnetic element with improved field response and fabricating method thereof |
US6169689B1 (en) * | 1999-12-08 | 2001-01-02 | Motorola, Inc. | MTJ stacked cell memory sensing method and apparatus |
US6233172B1 (en) * | 1999-12-17 | 2001-05-15 | Motorola, Inc. | Magnetic element with dual magnetic states and fabrication method thereof |
JP2001184870A (en) * | 1999-12-27 | 2001-07-06 | Mitsubishi Electric Corp | Associative memory and variable length encoder/decoder using the same |
US6185143B1 (en) * | 2000-02-04 | 2001-02-06 | Hewlett-Packard Company | Magnetic random access memory (MRAM) device including differential sense amplifiers |
US6911710B2 (en) * | 2000-03-09 | 2005-06-28 | Hewlett-Packard Development Company, L.P. | Multi-bit magnetic memory cells |
US6211090B1 (en) * | 2000-03-21 | 2001-04-03 | Motorola, Inc. | Method of fabricating flux concentrating layer for use with magnetoresistive random access memories |
US6205073B1 (en) * | 2000-03-31 | 2001-03-20 | Motorola, Inc. | Current conveyor and method for readout of MTJ memories |
JP3800925B2 (en) * | 2000-05-15 | 2006-07-26 | 日本電気株式会社 | Magnetic random access memory circuit |
DE10036140C1 (en) * | 2000-07-25 | 2001-12-20 | Infineon Technologies Ag | Non-destructive read-out of MRAM memory cells involves normalizing actual cell resistance, comparing normalized and normal resistance values, detecting content from the result |
JP4309075B2 (en) * | 2000-07-27 | 2009-08-05 | 株式会社東芝 | Magnetic storage |
US6363007B1 (en) * | 2000-08-14 | 2002-03-26 | Micron Technology, Inc. | Magneto-resistive memory with shared wordline and sense line |
US6538921B2 (en) * | 2000-08-17 | 2003-03-25 | Nve Corporation | Circuit selection of magnetic memory cells and related cell structures |
DE10041378C1 (en) * | 2000-08-23 | 2002-05-16 | Infineon Technologies Ag | MRAM configuration |
DE10043440C2 (en) * | 2000-09-04 | 2002-08-29 | Infineon Technologies Ag | Magnetoresistive memory and method for reading it out |
JP4693292B2 (en) * | 2000-09-11 | 2011-06-01 | 株式会社東芝 | Ferromagnetic tunnel junction device and manufacturing method thereof |
JP4726290B2 (en) * | 2000-10-17 | 2011-07-20 | ルネサスエレクトロニクス株式会社 | Semiconductor integrated circuit |
US6538919B1 (en) * | 2000-11-08 | 2003-03-25 | International Business Machines Corporation | Magnetic tunnel junctions using ferrimagnetic materials |
US6351409B1 (en) * | 2001-01-04 | 2002-02-26 | Motorola, Inc. | MRAM write apparatus and method |
US6385109B1 (en) * | 2001-01-30 | 2002-05-07 | Motorola, Inc. | Reference voltage generator for MRAM and method |
US6515895B2 (en) * | 2001-01-31 | 2003-02-04 | Motorola, Inc. | Non-volatile magnetic register |
US6358756B1 (en) * | 2001-02-07 | 2002-03-19 | Micron Technology, Inc. | Self-aligned, magnetoresistive random-access memory (MRAM) structure utilizing a spacer containment scheme |
US6466471B1 (en) * | 2001-05-29 | 2002-10-15 | Hewlett-Packard Company | Low power MRAM memory array |
WO2003019586A1 (en) * | 2001-08-30 | 2003-03-06 | Koninklijke Philips Electronics N.V. | Magnetoresistive device and electronic device |
US6633498B1 (en) * | 2002-06-18 | 2003-10-14 | Motorola, Inc. | Magnetoresistive random access memory with reduced switching field |
US6707083B1 (en) * | 2002-07-09 | 2004-03-16 | Western Digital (Fremont), Inc. | Magnetic tunneling junction with improved power consumption |
US6677631B1 (en) * | 2002-08-27 | 2004-01-13 | Micron Technology, Inc. | MRAM memory elements and method for manufacture of MRAM memory elements |
JP3931876B2 (en) * | 2002-11-01 | 2007-06-20 | 日本電気株式会社 | Magnetoresistive device and manufacturing method thereof |
JP2004179187A (en) * | 2002-11-22 | 2004-06-24 | Toshiba Corp | Magnetoresistive effect element and magnetic memory |
US6898112B2 (en) * | 2002-12-18 | 2005-05-24 | Freescale Semiconductor, Inc. | Synthetic antiferromagnetic structure for magnetoelectronic devices |
US6885073B2 (en) * | 2003-04-02 | 2005-04-26 | Micron Technology, Inc. | Method and apparatus providing MRAM devices with fine tuned offset |
KR100522943B1 (en) * | 2003-04-25 | 2005-10-25 | 학교법인고려중앙학원 | Magnetoresistive structure exhibiting small and stable bias fields independent of device size variation |
US6714446B1 (en) * | 2003-05-13 | 2004-03-30 | Motorola, Inc. | Magnetoelectronics information device having a compound magnetic free layer |
US6865109B2 (en) * | 2003-06-06 | 2005-03-08 | Seagate Technology Llc | Magnetic random access memory having flux closure for the free layer and spin transfer write mechanism |
JP4406250B2 (en) * | 2003-09-24 | 2010-01-27 | 株式会社東芝 | Spin tunnel transistor |
US6974708B2 (en) * | 2004-04-08 | 2005-12-13 | Headway Technologies, Inc. | Oxidation structure/method to fabricate a high-performance magnetic tunneling junction MRAM |
US7132707B2 (en) * | 2004-08-03 | 2006-11-07 | Headway Technologies, Inc. | Magnetic random access memory array with proximate read and write lines cladded with magnetic material |
US7187576B2 (en) * | 2004-07-19 | 2007-03-06 | Infineon Technologies Ag | Read out scheme for several bits in a single MRAM soft layer |
US7072208B2 (en) * | 2004-07-28 | 2006-07-04 | Headway Technologies, Inc. | Vortex magnetic random access memory |
JP4550552B2 (en) * | 2004-11-02 | 2010-09-22 | 株式会社東芝 | Magnetoresistive element, magnetic random access memory, and method of manufacturing magnetoresistive element |
-
2004
- 2004-11-24 US US10/997,118 patent/US7129098B2/en not_active Expired - Fee Related
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2005
- 2005-11-21 JP JP2007543529A patent/JP5080267B2/en active Active
- 2005-11-21 CN CNB2005800367221A patent/CN100530439C/en active Active
- 2005-11-21 WO PCT/US2005/042764 patent/WO2006058224A1/en active Application Filing
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Patent Citations (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US6531723B1 (en) * | 2001-10-16 | 2003-03-11 | Motorola, Inc. | Magnetoresistance random access memory for improved scalability |
US6545906B1 (en) * | 2001-10-16 | 2003-04-08 | Motorola, Inc. | Method of writing to scalable magnetoresistance random access memory element |
Also Published As
Publication number | Publication date |
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TWI398871B (en) | 2013-06-11 |
TW200632923A (en) | 2006-09-16 |
US20070037299A1 (en) | 2007-02-15 |
KR20070084511A (en) | 2007-08-24 |
JP5080267B2 (en) | 2012-11-21 |
US7329935B2 (en) | 2008-02-12 |
CN101048825A (en) | 2007-10-03 |
CN100530439C (en) | 2009-08-19 |
KR101247255B1 (en) | 2013-03-25 |
US20060108620A1 (en) | 2006-05-25 |
JP2008522415A (en) | 2008-06-26 |
US7129098B2 (en) | 2006-10-31 |
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