Abstract: An InGaAsN semiconductor light-emitting device containing one or more barrier layers is designed to prevent diffusion of one or more elements out of the quantum well. In one embodiment, the barrier layer can either contain nitrogen in substantially the same concentration as the InGaAsN layer or contain two or more group III elements in combination with nitrogen, where the fractional composition of the two or more group III elements and nitrogen is designed to minimize out-diffusion of nitrogen from the quantum well. In other embodiments, the barrier layer can contain indium and gallium to minimize In/Ga intermixing at the heterointerface to the quantum well. In further embodiments, a compressive-strained or lattice-matched intermediate layer can be added between the InGaAsN quantum well and a tensile-strained barrier layer to minimize strain-related out-diffusion of nitrogen.

Abstract: A method and system for growing a layer of semiconductor material is disclosed. The method can be used to grow a layer of a semiconducting material comprising at least one Group III element, nitrogen and at least one other Group V element as constituent elements thereof, the method comprising providing a reactor and supplying precursors to the reactor. The precursors include a precursor for each of the at least one Group III element, a precursor for the nitrogen, a precursor for each of the at least one Group V element other than nitrogen, and a precursor for an element having a stronger bond strength with nitrogen than each of the at least one Group III element has with nitrogen. The method can be implemented in, for example, a metal organic chemical vapor deposition (MOCVD) reactor.

Abstract: A method for making high quality InGaAsN semiconductor devices is presented. The method allows the making of high quality InGaAsN semiconductor devices using a single MOCVD reactor while avoiding aluminum contamination.

Abstract: Several methods for producing an active region for a long wavelength light emitting device are disclosed. In one embodiment, the method comprises placing a substrate in an organometallic vapor phase epitaxy (OMVPE) reactor, the substrate for supporting growth of an indium gallium arsenide nitride (InGaAsN) film, supplying to the reactor a group-III-V precursor mixture comprising arsine, dimethylhydrazine, alkyl-gallium, alkyl-indium and a carrier gas, where the arsine and the dimethylhydrazine are the group-V precursor materials and where the percentage of dimethylhydrazine substantially exceeds the percentage of arsine, and pressurizing the reactor to a pressure at which a concentration of nitrogen commensurate with light emission at a wavelength longer than 1.2 um is extracted from the dimethylhydrazine and deposited on the substrate.

Abstract: The group III-V semiconductor device comprises a quantum well layer, barrier layers sandwiching the quantum well layer and a region of a third semiconductor material formed by spatially-selective intermixing of atoms on the group V sublattice between the first semiconductor material of the quantum well layer and the second semiconductor material of the barrier layer. The quantum well layer is a layer of a first semiconductor material that has a band gap energy and a refractive index. The barrier layers are layers of a second semiconductor material that has a higher band gap energy and a lower refractive index than the first semiconductor material. The third semiconductor material has a band gap energy and a refractive index intermediate between the band gap energy and the refractive index, respectively, of the first semiconductor material and the second semiconductor material.

Abstract: A system for fabricating a light emitting device is disclosed. The system contains a growth chamber and at least one nitrogen precursor that is introduced to the growth chamber. The at least one nitrogen precursor has a direct bond between at least one group III atom and at least one nitrogen atom. In addition, the nitrogen precursor is used to fabricate a layer constituting part of an active region of the light emitting device containing indium, gallium, arsenic, and nitrogen, wherein the active region produces light having a wavelength in the range of approximately 1.2 to 1.6 micrometers. A method for fabricating a semiconductor structure is also disclosed. The method comprises providing a substrate and growing over the substrate a layer comprising indium, gallium, arsenic, and nitrogen using at least one nitrogen precursor having a direct bond between at least one group III atom and at least one nitrogen atom.

Abstract: The instant specification discloses a flat battery constituted by sealing a power generation element with: a case that works as one electrode terminal; a sealing plate that works as the other electrode terminal and has a flat central section projected outward and a flat peripheral section extending substantially parallel to the flat central section; and a gasket that insulates the case from the sealing plate, characterized in that the peripheral section of the sealing plate has an outer circumferential part being bent, or the case has a turned edge provided to make the peripheral section of the sealing plate fitted therein via the gasket and to partly press the gasket. The flat battery of the present invention having improvement in shape of the sealing plate and/or the case is sufficiently thin and exerts the effects of high leakage resistance and excellent mass productivity.

Abstract: A nitride semiconductor device that comprises a first layer, a second layer and a buffer layer sandwiched between the first layer and the second layer. The second layer is a layer of a single-crystal nitride semiconductor material including AlN and has a thickness greater than the thickness at which cracks would form if the second layer were grown directly on the first layer. The buffer layer is a layer of a low-temperature-deposited nitride semiconductor material that includes AlN. Incorporating the nitride semiconductor device into a semiconductor laser diode enables the laser diode to generate coherent light having a far-field pattern that exhibits a single peak.

Abstract: A light emitting device including a nucleation layer containing aluminum is disclosed. The thickness and aluminum composition of the nucleation layer are selected to match the index of refraction of the substrate and device layers, such that 90% of light from the device layers incident on the nucleation layer is extracted into the substrate. In some embodiments, the nucleation layer is AlGaN with a thickness between about 1000 and about 1200 angstroms and an aluminum composition between about 2% and about 8%. In some embodiments, the nucleation layer is formed over a surface of a wurtzite substrate that is miscut from the c-plane of the substrate. In some embodiments, the nucleation layer is formed at high temperature, for example between 900° and 1200° C. In some embodiments, the nucleation layer is doped with Si to a concentration between about 3e18 cm−3 and about 5e19 cm−3.

Abstract: Several methods for producing an active region for a long wavelength light emitting device are disclosed. In one embodiment, the method comprises placing a substrate in an organometallic vapor phase epitaxy (OMVPE) reactor, the substrate for supporting growth of an indium gallium arsenide nitride (InGaAsN) film, supplying to the reactor a group-III-V precursor mixture comprising arsine, dimethylhydrazine, alkyl-gallium, alkyl-indium and a carrier gas, where the arsine and the dimethylhydrazine are the group-V precursor materials and where the percentage of dimethylhydrazine substantially exceeds the percentage of arsine, and pressurizing the reactor to a pressure at which a concentration of nitrogen commensurate with light emission at a wavelength longer than 1.2 um is extracted from the dimethylhydrazine and deposited on the substrate.

Abstract: Various asymmetric InGaAsN VCSEL structures that are made using an MOCVD process are presented. Use of the asymmetric structure effectively eliminates aluminum contamination of the quantum well active region.

Abstract: A method for making high quality InGaAsN semiconductor devices is presented. The method allows the making of high quality InGaAsN semiconductor devices using a single MOCVD reactor while avoiding aluminum contamination.

Abstract: An optical semiconductor device having a plurality of GaN-based semiconductor layers containing a strained quantum well layer in which the strained quantum well layer has a piezoelectric field that depends on the orientation of the strained quantum well layer when the quantum layer is grown. In the present invention, the strained quantum well layer is grown with an orientation at which the piezoelectric field is less than the maximum value of the piezoelectric field strength as a function of the orientation. In devices having GaN-based semiconductor layers with a wurtzite crystal structure, the growth orientation of the strained quantum well layer is tilted at least 1° from the {0001} direction of the wurtzite crystal structure. In devices having GaN-based semiconductor layers with a zincblende crystal structure, the growth orientation of the strained quantum well layer is tilted at least 1° from the {111} direction of the zincblende crystal structure.

Abstract: A light emitting device including a nucleation layer containing aluminum is disclosed. The thickness and aluminum composition of the nucleation layer are selected to match the index of refraction of the substrate and device layers, such that 90% of light from the device layers incident on the nucleation layer is extracted into the substrate. In some embodiments, the nucleation layer is AlGaN with a thickness between about 1000 and about 1200 angstroms and an aluminum composition between about 2% and about 8%. In some embodiments, the nucleation layer is formed over a surface of a wurtzite substrate that is miscut from the c-plane of the substrate. In some embodiments, the nucleation layer is formed at high temperature, for example between 900° and 1200° C. In some embodiments, the nucleation layer is doped with Si to a concentration between about 3e18 cm−3 and about 5e19 cm−3.

Abstract: A substrate for fabricating semiconductor devices based on Group III semiconductors and the method for making the same. A substrate according to the present invention includes a base substrate, a first buffer layer, and a first single crystal layer. The first buffer layer includes a Group III material deposited on the base substrate at a temperature below that at which the Group III material crystallizes. The Group III material is crystallized by heating the buffer layer to a temperature above that at which the Group III material crystallizes to form a single crystal after the Group III material has been deposited. The first single crystal layer includes a Group III-V semiconducting material deposited on the first buffer layer at a temperature above that at which the Group III semiconducting material crystallizes. In one embodiment of the present invention, a second buffer layer and a second single crystal layer are deposited on the first single crystal layer.

Abstract: A nitride semiconductor epitaxial substrate includes a low-temperature-deposited buffer layer, the composition of which is AlxGa1−xN, where 0≦x≦1, and a single crystalline layer, the composition of which is AlyGa1−yN, where 0>y≦1. The single crystalline layer is deposited directly over the low-temperature-deposited buffer layer, wherein the buffer layer has a mole fraction x satisfying (y−0.3)≦x>y.

Abstract: A light emitting device in accordance with an embodiment of the present invention includes a first semiconductor layer of a first conductivity type having a first surface, and an active region formed overlying the first semiconductor layer. The active region includes a second semiconductor layer which is either a quantum well layer or a barrier layer. The second semiconductor layer is formed from a semiconductor alloy having a composition graded in a direction substantially perpendicular to the first surface of the first semiconductor layer. The light emitting device also includes a third semiconductor layer of a second conductivity type formed overlying the active region.

Abstract: A gasket-integrated case is obtained by punching out a circular piece from a metal sheet on which a gasket resin film having a round hole is integrally laminated with an adhesive, in such a way as to have a diameter concentric with, but larger than, the round hole, and by drawing the circular piece into a bottomed cylindrical shape. Elements for electromotive force and a sealing plate are then disposed on the case, and the periphery of the sealing plate is sandwiched and sealed by the periphery of the case by crimping, with a gasket including the resin film interposed therebetween, so that a coin-shaped battery is formed. The resin film has a thickness in the range of 20 &mgr;m to 150 &mgr;m and a modulus of elasticity equal to or greater than 35 kgf/mm2.

Abstract: An optical semiconductor device having an active layer for generating light via the recombination of holes and electrons therein. The active layer is part of a plurality of semiconductor layers including an n-p junction between an n-type layer and a p-type layer. The active layer has a polarization field therein having a field direction that depends on the orientation of the active layer when the active layer is grown. In the present invention, the polarization field in the active layer has an orientation such that the polarization field is directed from the n-layer to the p-layer.

Abstract: The nitride semiconductor layer structure comprises a buffer layer and a composite layer on the buffer layer. The buffer layer is a layer of a low-temperature-deposited nitride semiconductor material that includes AlN. The composite layer is a layer of a single-crystal nitride semiconductor material that includes AlN. The composite layer includes a first sub-layer adjacent the buffer layer and a second sub-layer over the first sub-layer. The single-crystal nitride semiconductor material of the composite layer has a first AlN molar fraction in the first sub-layer and has a second AlN molar fraction in the second sub-layer. The second AlN molar fraction is greater than the first AlN molar fraction. The nitride semiconductor laser comprises a portion of the above-described nitride semiconductor layer structure, and additionally comprises an optical waveguide layer over the composite layer and an active layer over the optical waveguide layer.