Abstract: 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.

Abstract: 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.

Abstract: 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.

Abstract: 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.

Abstract: 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.

Abstract: 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.

Abstract: 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.

Abstract: 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.

Abstract: A solution for treating a fluid, such as water, is provided. The solution first removes a set of target contaminants that may be present in the fluid using a filtering solution. The filtered fluid enters a disinfection chamber where it is irradiated by ultraviolet radiation to harm microorganisms that may be present in the fluid. An ultraviolet radiation source and/or the disinfection chamber can include one or more attributes configured to provide more efficient irradiation and/or higher disinfection rates.

Abstract: 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.

Abstract: 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.

Abstract: 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.

Abstract: 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).

Abstract: 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.