Cree Inc.

About: Cree Inc. is a company organization based out in Shenzhen, China. It is known for research contribution in the topics: Layer (electronics) & Silicon carbide. The organization has 1014 authors who have published 2436 publications receiving 64884 citations.

Solid State Directional Lamp Including Retroreflective, Multi-Element Directional Lamp Optic

Abstract: A solid state directional lamp is disclosed. The lamp comprises a reflector and a plurality of solid state light emitters directing light rays towards the reflector. For each solid state light emitter of the plurality of solid state light emitters, the reflector defines a segmented parabola and a mirrored wall associated with the light emitter. Each solid state light emitter is positioned in the lamp at a focal point of the segmented parabola associated with the solid state light emitter. For each solid state light, the mirrored wall associated with the solid state light emitter directs light rays from the solid state light emitter into the segmented parabola associated with the same solid state light emitter.

Passive phase change radiators for LED lamps and fixtures

Abstract: Heat management devices and structures are disclosed that can be used in lamps having solid state light sources such as one or more LEDs. Some lamp embodiments comprise one or more phase change radiators that utilize the latent heat of fluids to circulate and draw heat away from the LEDs and radiate the heat into the ambient, allowing for the LEDs to operate at a lower temperature. Some phase change radiators according to the present invention can comprise a main radiator body and multiple radiator coolant loops mounted to the body. The present invention relies on the circulation of heated fluid through the radiator body to radiate heat from the LEDs. The heated liquid moves away from the LEDs and is circulated back to thermal contact with the LEDs thought the coolant loops.

Monolithic bidirectional silicon carbide switching devices and methods of forming the same

Abstract: A monolithic bidirectional switching device includes a drift layer having a first conductivity type and having an upper surface, and first and second vertical metal-oxide semiconductor (MOS) structures at the upper surface of the drift layer. The drift layer provides a common drain for the first and second vertical MOS structures. The first and second vertical MOS structures are protected by respective first and second edge termination structures at the upper surface of the drift layer. A monolithic bidirectional switching device according to further embodiments includes a vertical MOS structure at the upper surface of the drift layer, and a diode at the upper surface of the drift layer. The drift layer provides a drain for the vertical MOS structure and a cathode for the diode, and the vertical MOS structure and the diode are protected by respective first and second edge termination structures.

Transition from brittle fracture to ductile behavior in 4H–SiC

Abstract: The four-point bend test was used to measure the brittle-to-ductile transition (BDT) temperature in precracked samples of semi-insulating 4H—SiC at four different strain rates. As in other semiconductors, the BDT temperature TBDT was found to be very sharp, within ±15 °C, and to shift to higher temperatures with increasing rates of the applied load (or strain rate). The results appear to be consistent with a transition temperature Tc recently observed in the yield stress of the same material as measured by compression experiments. However, strain-rate measurements in four-point bend tests are not strictly equivalent to those in compression experiments, and therefore it is difficult to directly compare the measured BDT temperatures with the yield stress transitions. Nevertheless, it is believed that the reasonable agreement between TBDT and Tc supports the model recently proposed to explain these transition temperatures.

Modular LED lighting system

Abstract: This disclosure relates to LED based lighting systems, such as surface mounted lighting systems and lighting systems that can connected to an existing grid structure. These lighting systems can be utilized in many settings, for example, as primary lighting systems for a commercial building and for retrofit lighting improvement purposes. Devices according to the present disclosure provide lighting systems capable of mounting to an existing surface, such as a T-bar ceiling structure. These devices can further comprise modular elements which facilitate connections of multiple lighting body components, allowing for multiple lighting arrangements and providing a cost effective and easily configurable lighting design. In some embodiments, multiple lighting components can be attached together by movable joints, allowing further user control over light distribution from the lighting systems.