Abstract: A light fixture having master circuit boards and one or more LED circuit boards connectable in various alternative combinations for light fixtures having alternative lengths, the master board including a switch and AC-DC rectifier and the LED boards including linear AC drivers and one or more LED arrays, the switch on the master board controlling the linear AC drivers on the LED board or boards.

Abstract: Systems and methods for characterizing solid state lighting devices are provided. In certain examples, systems and methods for measuring various parameters of light emitting diodes (LEDs), characterizing each LED based on the measured parameters and selecting one or more of the characterized LEDs such that the emitted light from each of the selected LEDs is mixed with the light from the other selected LEDs to create a desired overall light output are described.

Abstract: The invention provides gallium nitride material devices, structures and methods of forming the same. The devices include a gallium nitride material formed over a substrate, such as silicon. Exemplary devices include light emitting devices (e.g., LED's, lasers), light detecting devices (such as detectors and sensors), power rectifier diodes and FETs (e.g., HFETs), amongst others.

Abstract: The invention includes providing gallium nitride materials including thermally conductive regions and methods to form such materials. The gallium nitride materials may be used to form semiconductor devices. The thermally conductive regions may include heat spreading layers and heat sinks. Heat spreading layers distribute beat generated during device operation over relatively large areas to prevent excessive localized heating. Heat sinks typically are formed at either the backside or topside of the device and facilitate heat dissipation to the environment. It may be preferable for devices to include a heat spreading layer which is connected to a heat sink at the backside of the device. A variety of semiconductor devices may utilize features of the invention including devices on silicon substrates and devices which generate large amounts of heat such as power transistors.

Abstract: The invention provides gallium nitride material devices, structures and methods of forming the same. The devices include a gallium nitride material formed over a substrate, such as silicon. Exemplary devices include light emitting devices (e.g., LED's, lasers), light detecting devices (such as detectors and sensors), power rectifier diodes and FETs (e.g., HFETs), amongst others.

Abstract: The invention provides semiconductor materials including a gallium nitride material layer formed on a silicon substrate and methods to form the semiconductor materials. The semiconductor materials include a transition layer formed between the silicon substrate and the gallium nitride material layer. The transition layer is compositionally-graded to lower stresses in the gallium nitride material layer which can result from differences in thermal expansion rates between the gallium nitride material and the substrate. The lowering of stresses in the gallium nitride material layer reduces the tendency of cracks to form. Thus, the invention enables the production of semiconductor materials including gallium nitride material layers having few or no cracks. The semiconductor materials may be used in a number of microelectronic and optical applications.

Abstract: The invention includes providing gallium nitride material devices having backside vias and methods to form the devices. The devices include a gallium nitride material formed over a substrate, such as silicon. The device also may include one or more non-conducting layers between the substrate and the gallium nitride material which can aid in the deposition of the gallium nitride material. A via is provided which extends from the backside of the device through the non-conducting layer(s) to enable electrical conduction between an electrical contact deposited within the via and, for example, an electrical contact on the topside of the device. Thus, devices of the invention may be vertically conducting. Exemplary devices include laser diodes (LDs), light emitting diodes (LEDs), power rectifier diodes, FETs (e.g., HFETs), Gunn-effect diodes, and varactor diodes, among others.

Abstract: The invention provides semiconductor structures that include a gallium nitride material component and a silicon germanium component, as well as methods of forming such structures. The gallium nitride material component may be a layer formed on a substrate, or may be the substrate itself. Similarly, the silicon germanium component may be a layer formed on a substrate, or may be the substrate itself. Crack formation within the two components can be limited by matching the thermal expansion rates of the gallium nitride material and the silicon germanium and, thus, inhibiting the generation of thermal stresses within the components. The semiconductor structures may be used in a number of microelectronic and optoelectronic applications, amongst others.

Abstract: The invention provides semiconductor materials including a gallium nitride material layer formed on a silicon substrate and methods to form the semiconductor materials. The semiconductor materials include a transition layer formed between the silicon substrate and the gallium nitride material layer. The transition layer is compositionally-graded to lower stresses in the gallium nitride material layer which can result from differences in thermal expansion rates between the gallium nitride material and the substrate. The lowering of stresses in the gallium nitride material layer reduces the tendency of cracks to form. Thus, the invention enables the production of semiconductor materials including gallium nitride material layers having few or no cracks. The semiconductor materials may be used in a number of microelectronic and optical applications.

Abstract: The invention includes providing gallium nitride materials including thermally conductive regions and methods to form such materials. The gallium nitride materials may be used to form semiconductor devices. The thermally conductive regions may include heat spreading layers and heat sinks. Heat spreading layers distribute heat generated during device operation over relatively large areas to prevent excessive localized heating. Heat sinks typically are formed at either the backside or topside of the device and facilitate heat dissipation to the environment. It may be preferable for devices to include a heat spreading layer which is connected to a heat sink at the backside of the device. A variety of semiconductor devices may utilize features of the invention including devices on silicon substrates and devices which generate large amounts of heat such as power transistors.

Abstract: The invention includes providing gallium nitride material devices having backside vias and methods to form the devices. The devices include a gallium nitride material formed over a substrate, such as silicon. The device also may include one or more non-conducting layers between the substrate and the gallium nitride material which can aid in the deposition of the gallium nitride material. A via is provided which extends from the backside of the device through the non-conducting layer(s) to enable electrical conduction between an electrical contact deposited within the via and, for example, an electrical contact on the topside of the device. Thus, devices of the invention may be vertically conducting. Exemplary devices include laser diodes (LDs), light emitting diodes (LEDs), power rectifier diodes, FETs (e.g., HFETs), Gunn-effect diodes, and varactor diodes, among others.

Abstract: The invention provides semiconductor materials including a gallium nitride material layer formed on a silicon substrate and methods to form the semiconductor materials. The semiconductor materials include a transition layer formed between the silicon substrate and the gallium nitride material layer. The transition layer is compositionally-graded to lower stresses in the gallium nitride material layer which can result from differences in thermal expansion rates between the gallium nitride material and the substrate. The lowering of stresses in the gallium nitride material layer reduces the tendency of cracks to form. Thus, the invention enables the production of semiconductor materials including gallium nitride material layers having few or no cracks. The semiconductor materials may be used in a number of microelectronic and optical applications.