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 metal block mounting substrates for semiconductor light emitting devices

Abstract: A mounting substrate for a semiconductor light emitting device includes a solid metal block having a cavity in a face thereof that is configured for mounting a semiconductor light emitting device therein. An insulating coating is provided in the cavity, and first and second spaced apart conductive traces are provided on the insulating coating in the cavity that are configured for connection to a semiconductor light emitting device. The mounting substrate may be fabricated by providing a solid aluminum block including a cavity in a face thereof that is configured for mounting a semiconductor light emitting device therein. The solid aluminum block is oxidized to form an aluminum oxide coating thereon. The first and second spaced apart electrical traces are fabricated on the aluminum oxide coating in the cavity.

Light transmission control for masking appearance of solid state light sources

Abstract: A light emitter device, package, or lamp that comprises and light emitter and a light transmission control material to mask the appearance of at least the light emitter. In one embodiment, a light emitting diode (LED) based lamp is disclosed, comprising an LED light source. A phosphor is arranged remote to the light source such that light emitted from the light source passes through this phosphor and is converted by this phosphor. A light transmission control material is applied at least partially outside the LED light source and the phosphor to reversibly mask the appearance of the LED light source and the phosphor. The light transmission control material is less masking when the LED light source is active. A method for masking the appearance of inactive light emitters is also disclosed that comprising providing at least one light emitter. Each of the at least one light emitters is provided with a light transmission control material over the light emitters to reversibly mask the appearance of the light emitters while the light emitters are inactive. The light transmission control material is less masking when the LED light source is active.

Light emitting diode with improved light extraction

Abstract: A light emitting diode (70) is disclosed that includes an active region (83) and a plurality of exterior surfaces (77-81). A light enhancement feature is present on at least portions of one of the exterior surfaces of the diode, with the light enhancement feature being selected from the group consisting of shaping (77, 80) and texturing (78, 79). A light enhancement feature is present on at least portions of each of the other exterior surfaces (81) of the diode, with these light enhancement features being selected from the group consisting of shaping, texturing, and reflectors (81).

Conformally coated light emitting devices and methods for providing the same

Abstract: Methods are disclosed including applying a conformal coating to multiple light emitters. The conformal coating forms in gap areas between adjacent ones of the light emitters. The plurality of light emitters are separated into individual light emitters. The individual light emitters include the conformal coating that extends to a space corresponding to respective gap areas. Light emitting structures are disclosed including a semiconductor light emitting diode (LED) having an active region and a conformal coating including a first portion and a second portion, the first portion corresponding to at least one surface of the LED and the second portion extending from the first portion.

High power demonstration at 10 GHz with GaN-AlGaN HEMT hybrid amplifiers

Abstract: The GaN/AlGaN-on-SiC HEMT is being pursued as an RF power device on which to base next generation X-band and K-band power amplifiers. Previous demonstrations of extremely high power density and total RF power from GaN/AlGaN HEMTs on SI SiC substrates (Sheppard et al., 1999; Wu et al., 1999) adequately demonstrate their potential for improved performance over GaAs-based devices. Considering the recent advances in III-nitride growth and processing techniques, it is not surprising that GaN/AlGaN HEMTs on SiC substrates are beginning to the reach the extremely high power levels that have been predicted for this material system. To continue this trend, we are pursuing high quality HEMT structures with 15% AlGaN molar fraction (MF) in order to fabricate large area devices and demonstrate high power levels. We report the demonstration of over 40 W from a single GaN/AlGaN transistor at 10 GHz under pulsed mode conditions. This high power demonstration includes the first implementation of SiC substrate vias on a GaN-on-SiC microwave transistor for improved gain at X-band.