Patent application number | Description | Published |
20110138341 | Semiconductor Material Doping - A solution for designing and/or fabricating a structure including a quantum well and an adjacent barrier is provided. A target band discontinuity between the quantum well and the adjacent barrier is selected to coincide with an activation energy of a dopant for the quantum well and/or barrier. For example, a target valence band discontinuity can be selected such that a dopant energy level of a dopant in the adjacent barrier coincides with a valence energy band edge for the quantum well and/or a ground state energy for free carriers in a valence energy band for the quantum well. The quantum well and the adjacent barrier can be formed such that the actual band discontinuity corresponds to the target band discontinuity. | 06-09-2011 |
20110253975 | Semiconductor Material Doping - A solution for designing and/or fabricating a structure including a quantum well and an adjacent barrier is provided. A target band discontinuity between the quantum well and the adjacent barrier is selected to coincide with an activation energy of a dopant for the quantum well and/or barrier. For example, a target valence band discontinuity can be selected such that a dopant energy level of a dopant in the adjacent barrier coincides with a valence energy band edge for the quantum well and/or a ground state energy for free carriers in a valence energy band for the quantum well. Additionally, a target doping level for the quantum well and/or adjacent barrier can be selected to facilitate a real space transfer of holes across the barrier. The quantum well and the adjacent barrier can be formed such that the actual band discontinuity and/or actual doping level(s) correspond to the relevant target(s). | 10-20-2011 |
20110309326 | DEEP ULTRAVIOLET LIGHT EMITTING DIODE - A light emitting diode is provided, which includes an n-type contact layer and a light generating structure adjacent to the n-type contact layer. The light generating structure includes a set of quantum wells. The contact layer and light generating structure can be configured so that a difference between an energy of the n-type contact layer and an electron ground state energy of a quantum well is greater than an energy of a polar optical phonon in a material of the light generating structure. Additionally, the light generating structure can be configured so that its width is comparable to a mean free path for emission of a polar optical phonon by an electron injected into the light generating structure. The diode can include a blocking layer, which is configured so that a difference between an energy of the blocking layer and the electron ground state energy of a quantum well is greater than the energy of the polar optical phonon in the material of the light generating structure. The diode can include a composite contact, including an adhesion layer, which is at least partially transparent to light generated by the light generating structure and a reflecting metal layer configured to reflect at least a portion of the light generated by the light generating structure. | 12-22-2011 |
20120201264 | LIGHT EMITTING DEVICE WITH VARYING BARRIERS - An emitting device including an active region having quantum wells alternating with barriers of varying compositions is provided. The barriers can be composed of a group III-nitride based material, in which a molar fraction of one or more of the group III elements in two barriers adjacent to a single quantum well differ by at least one percent. Two barriers adjacent to a single quantum well can have barrier heights differing by at least one percent. | 08-09-2012 |
20130032835 | Device with Inverted Large Scale Light Extraction Structures - An interface including roughness components for improving the propagation of radiation through the interface is provided. The interface includes a first profiled surface of a first layer comprising a set of large roughness components providing a first variation of the first profiled surface having a first characteristic scale and a second profiled surface of a second layer comprising a set of small roughness components providing a second variation of the second profiled surface having a second characteristic scale. The first characteristic scale is approximately an order of magnitude larger than the second characteristic scale. The surfaces can be bonded together using a bonding material, and a filler material also can be present in the interface. | 02-07-2013 |
20130056770 | Patterned Substrate Design for Layer Growth - A patterned surface for improving the growth of semiconductor layers, such as group III nitride-based semiconductor layers, is provided. The patterned surface can include a set of substantially flat top surfaces and a plurality of openings. Each substantially flat top surface can have a root mean square roughness less than approximately 0.5 nanometers, and the openings can have a characteristic size between approximately 0.1 micron and five microns. | 03-07-2013 |
20130078411 | Ultraviolet Device Encapsulant - A composite material, which can be used as an encapsulant for an ultraviolet device, is provided. The composite material includes a matrix material and at least one filler material incorporated in the matrix material that are both at least partially transparent to ultraviolet radiation of a target wavelength. The filler material includes microparticles and/or nanoparticles and can have a thermal coefficient of expansion significantly smaller than a thermal coefficient of expansion of the matrix material for relevant atmospheric conditions. The relevant atmospheric conditions can include a temperature and a pressure present during each of: a curing and a cool down process for fabrication of a device package including the composite material and normal operation of the ultraviolet device within the device package. | 03-28-2013 |
20130146907 | Ultraviolet Reflective Contact - A contact including an ohmic layer and a reflective layer located on the ohmic layer is provided. The ohmic layer is transparent to radiation having a target wavelength, while the reflective layer is at least approximately eighty percent reflective of radiation having the target wavelength. The target wavelength can be ultraviolet light, e.g., having a wavelength within a range of wavelengths between approximately 260 and approximately 360 nanometers. | 06-13-2013 |
20130193409 | Deep Ultraviolet Light Emitting Diode - A light emitting diode is provided, which includes an n-type contact layer and a light generating structure adjacent to the n-type contact layer. The light generating structure includes a set of quantum wells. The contact layer and light generating structure can be configured so that a difference between an energy of the n-type contact layer and an electron ground state energy of a quantum well is greater than an energy of a polar optical phonon in a material of the light generating structure. Additionally, the light generating structure can be configured so that its width is comparable to a mean free path for emission of a polar optical phonon by an electron injected into the light generating structure. | 08-01-2013 |
20130193480 | Epitaxy Technique for Reducing Threading Dislocations in Stressed Semiconductor Compounds - A solution for fabricating a semiconductor structure is provided. The semiconductor structure includes a plurality of semiconductor layers grown over a substrate using a set of epitaxial growth periods. During each epitaxial growth period, a first semiconductor layer having one of: a tensile stress or a compressive stress is grown followed by growth of a second semiconductor layer having the other of: the tensile stress or the compressive stress directly on the first semiconductor layer. One or more of a set of growth conditions, a thickness of one or both of the layers, and/or a lattice mismatch between the layers can be configured to create a target level of compressive and/or shear stress within a minimum percentage of the interface between the layers. | 08-01-2013 |
20130221406 | Ohmic Contact to Semiconductor - A solution for forming an ohmic contact to a semiconductor layer is provided. A masking material is applied to a set of contact regions on the surface of the semiconductor layer. Subsequently, one or more layers of a device heterostructure are formed on the non-masked region(s) of the semiconductor layer. The ohmic contact can be formed after the one or more layers of the device heterostructure are formed. The ohmic contact formation can be performed at a processing temperature lower than a temperature range within which a quality of a material forming any semiconductor layer in the device heterostructure is damaged. | 08-29-2013 |
20130260490 | Light Emitting Device Substrate with Inclined Sidewalls - A light emitting device having improved light extraction is provided. The light emitting device can be formed by epitaxially growing a light emitting structure on a surface of a substrate. The substrate can be scribed to form a set of angled side surfaces on the substrate. For each angled side surface in the set of angled side surfaces, a surface tangent vector to at least a portion of each angled side surface in the set of angled side surfaces forms an angle between approximately ten and approximately eighty degrees with a negative of a normal vector of the surface of the substrate. The substrate can be cleaned to clean debris from the angled side surfaces. | 10-03-2013 |
20130270445 | Ultraviolet-Based Sterilization - A system for sterilizing at least one surface of an object is provided. The system includes a set of ultraviolet radiation sources and a set of wave guiding structures configured to direct ultraviolet radiation having a set of target attributes to a desired location on at least one surface of the object. The set of wave guiding structures can include at least one ultraviolet reflective surface having an ultraviolet reflection coefficient of at least thirty percent. Furthermore, the system can include a computer system for operating the ultraviolet radiation sources to deliver a target dose of ultraviolet radiation to the at least one target surface of the object. | 10-17-2013 |
20130270519 | Non-Uniform Multiple Quantum Well Structure - A light emitting heterostructure including one or more fine structure regions is provided. The light emitting heterostructure can include a plurality of barriers alternating with a plurality of quantum wells. One or more of the barriers and/or quantum wells includes a fine structure region. The fine structure region includes a plurality of subscale features arranged in at least one of: a growth or a lateral direction. | 10-17-2013 |
20130320352 | Ohmic Contact to Semiconductor Layer - A perforating ohmic contact to a semiconductor layer in a semiconductor structure is provided. The perforating ohmic contact can include a set of perforating elements, which can include a set of metal protrusions laterally penetrating the semiconductor layer(s). The perforating elements can be separated from one another by a characteristic length scale selected based on a sheet resistance of the semiconductor layer and a contact resistance per unit length of a metal of the perforating ohmic contact contacting the semiconductor layer. The structure can be annealed using a set of conditions configured to ensure formation of the set of metal protrusions. | 12-05-2013 |
20140008675 | Emitting Device with Improved Extraction - A profiled surface for improving the propagation of radiation through an interface is provided. The profiled surface includes a set of large roughness components providing a first variation of the profiled surface having a characteristic scale approximately an order of magnitude larger than a target wavelength of the radiation. The profiled surface also includes a set of small roughness components superimposed on the set of large roughness components and providing a second variation of the profiled surface having a characteristic scale on the order of the target wavelength of the radiation. | 01-09-2014 |
20140016660 | Metallic Contact for Optoelectronic Semiconductor Device - A contact to a semiconductor layer in a light emitting structure is provided. The contact can include a plurality of contact areas formed of a metal and separated by a set of voids. The contact areas can be separated from one another by a characteristic distance selected based on a set of attributes of a semiconductor contact structure of the contact and a characteristic contact length scale of the contact. The voids can be configured to increase an overall reflectivity or transparency of the contact. | 01-16-2014 |
20140064314 | Emitting Device with Compositional and Doping Inhomogeneities in Semiconductor Layers - A device including one or more layers with lateral regions configured to facilitate the transmission of radiation through the layer and lateral regions configured to facilitate current flow through the layer is provided. The layer can comprise a short period superlattice, which includes barriers alternating with wells. In this case, the barriers can include both transparent regions, which are configured to reduce an amount of radiation that is absorbed in the layer, and higher conductive regions, which are configured to keep the voltage drop across the layer within a desired range. | 03-06-2014 |
20140077154 | Semiconductor Material Doping - A solution for designing and/or fabricating a structure including a quantum well and an adjacent barrier is provided. A target band discontinuity between the quantum well and the adjacent barrier is selected to coincide with an activation energy of a dopant for the quantum well and/or barrier. For example, a target valence band discontinuity can be selected such that a dopant energy level of a dopant in the adjacent barrier coincides with a valence energy band edge for the quantum well and/or a ground state energy for free carriers in a valence energy band for the quantum well. Additionally, a target doping level for the quantum well and/or adjacent barrier can be selected to facilitate a real space transfer of holes across the barrier. The quantum well and the adjacent barrier can be formed such that the actual band discontinuity and/or actual doping level(s) correspond to the relevant target(s). | 03-20-2014 |
20140110754 | Epitaxy Technique for Growing Semiconductor Compounds - A solution for fabricating a semiconductor structure is provided. The semiconductor structure includes a plurality of semiconductor layers grown over a substrate using a set of epitaxial growth periods. During each epitaxial growth period, a first semiconductor layer having one of: a tensile stress or a compressive stress is grown followed by growth of a second semiconductor layer having the other of: the tensile stress or the compressive stress directly on the first semiconductor layer. | 04-24-2014 |
20140134773 | Patterned Layer Design for Group III Nitride Layer Growth - A method of fabricating a device using a layer with a patterned surface for improving the growth of semiconductor layers, such as group III nitride-based semiconductor layers with a high concentration of aluminum, is provided. The patterned surface can include a substantially flat top surface and a plurality of stress reducing regions, such as openings. The substantially flat top surface can have a root mean square roughness less than approximately 0.5 nanometers, and the stress reducing regions can have a characteristic size between approximately 0.1 microns and approximately five microns and a depth of at least 0.2 microns. A layer of group-III nitride material can be grown on the first layer and have a thickness at least twice the characteristic size of the stress reducing regions. | 05-15-2014 |
20140158980 | Emitting Device with Compositional and Doping Inhomogeneities in Semiconductor Layers - A device including one or more layers with lateral regions configured to facilitate the transmission of radiation through the layer and lateral regions configured to facilitate current flow through the layer is provided. The layer can comprise a short period superlattice, which includes barriers alternating with wells. In this case, the barriers can include both transparent regions, which are configured to reduce an amount of radiation that is absorbed in the layer, and higher conductive regions, which are configured to keep the voltage drop across the layer within a desired range. | 06-12-2014 |
20140191261 | Light Emitting Heterostructure with Partially Relaxed Semiconductor Layer - A light emitting heterostructure including a partially relaxed semiconductor layer is provided. The partially relaxed semiconductor layer can be included as a sublayer of a contact semiconductor layer of the light emitting heterostructure. A dislocation blocking structure also can be included adjacent to the partially relaxed semiconductor layer. | 07-10-2014 |
20140191398 | Ultraviolet Reflective Rough Adhesive Contact - A device including a first semiconductor layer and a contact to the first semiconductor layer is disclosed. An interface between the first semiconductor layer and the contact includes a first roughness profile having a characteristic height and a characteristic width. The characteristic height can correspond to an average vertical distance between crests and adjacent valleys in the first roughness profile. The characteristic width can correspond to an average lateral distance between the crests and adjacent valleys in the first roughness profile. | 07-10-2014 |
20140239312 | Semiconductor Structure with Inhomogeneous Regions - A semiconductor layer including a plurality of inhomogeneous regions is provided. Each inhomogeneous region has one or more attributes that differ from a material forming the semiconductor layer. The inhomogeneous regions can include one or more regions configured based on radiation having a target wavelength. These regions can include transparent and/or reflective regions. The inhomogeneous regions also can include one or more regions having a higher conductivity than a conductivity of the radiation-based regions, e.g., at least ten percent higher. | 08-28-2014 |
20140326950 | Stress Relieving Semiconductor Layer - A semiconductor structure, such as a group III nitride-based semiconductor structure is provided. The semiconductor structure includes a cavity containing semiconductor layer. The cavity containing semiconductor layer can have a thickness greater than two monolayers and a multiple cavities. The cavities can have a characteristic size of at least one nanometer and a characteristic separation of at least five nanometers. | 11-06-2014 |
20140346441 | Semiconductor Layer Including Compositional Inhomogeneities - A device comprising a semiconductor layer including a plurality of compositional inhomogeneous regions is provided. The difference between an average band gap for the plurality of compositional inhomogeneous regions and an average band gap for a remaining portion of the semiconductor layer can be at least thermal energy. Additionally, a characteristic size of the plurality of compositional inhomogeneous regions can be smaller than an inverse of a dislocation density for the semiconductor layer. | 11-27-2014 |
20150048309 | Device with Transparent and Higher Conductive Regions in Lateral Cross Section of Semiconductor Layer - A device including one or more layers with lateral regions configured to facilitate the transmission of radiation through the layer and lateral regions configured to facilitate current flow through the layer is provided. The layer can comprise a short period superlattice, which includes barriers alternating with wells. In this case, the barriers can include both transparent regions, which are configured to reduce an amount of radiation that is absorbed in the layer, and higher conductive regions, which are configured to keep the voltage drop across the layer within a desired range. | 02-19-2015 |
20150060908 | Optoelectronic Device with Modulation Doping - An improved heterostructure for an optoelectronic device is provided. The heterostructure includes an active region, an electron blocking layer, and a p-type contact layer. The p-type contact layer and electron blocking layer can be doped with a p-type dopant. The dopant concentration for the electron blocking layer can be at most ten percent the dopant concentration of the p-type contact layer. A method of designing such a heterostructure is also described. | 03-05-2015 |
20150064822 | Deep Ultraviolet Light Emitting Diode - A method of fabricating a light emitting diode, which includes an n-type contact layer and a light generating structure adjacent to the n-type contact layer, is provided. The light generating structure includes a set of quantum wells. The contact layer and light generating structure can be configured so that a difference between an energy of the n-type contact layer and an electron ground state energy of a quantum well is greater than an energy of a polar optical phonon in a material of the light generating structure. Additionally, the light generating structure can be configured so that its width is comparable to a mean free path for emission of a polar optical phonon by an electron injected into the light generating structure. | 03-05-2015 |
20150069270 | Storage Device Including Target UV Illumination Ranges - Ultraviolet radiation is directed within an area at target wavelengths, target intensities, a target temporal distribution, and/or a target spatial distribution. The target attribute(s) of the ultraviolet radiation can correspond to at least one of a plurality of selectable operating configurations including a storage life preservation operating configuration, a disinfection operating configuration, an ethylene decomposition operating configuration, and/or the like. | 03-12-2015 |
20150083994 | Group III Nitride Heterostructure for Optoelectronic Device - Heterostructures for use in optoelectronic devices are described. One or more parameters of the heterostructure can be configured to improve the reliability of the corresponding optoelectronic device. The materials used to create the active structure of the device can be considered in configuring various parameters the n-type and/or p-type sides of the heterostructure. | 03-26-2015 |