Cree Gmbh

Cree Microwave, Inc.

Research Triangle Institute

Sandia Corporation

Cree Research Inc.

David Beardsley Slater, Jr

John Adam Edmond

Gerald H Negley

Matthew Donofrio

Peter Scott Andrews

Alexander V Suvorov

Jayesh Bharathan

Brian Thibeault

Bernd P Keller

James Ibbetson

Hua-Shuang Kong

Bradley E Williams

Michael John Bergmann

Eric J Tarsa

Anwar Mohammed

Scott Thomas Allen

Kathleen Marie Doverspike

Charles M Swoboda

Robert C Glass

Davis Andrew McClure

Heidi Marie Dieringer

Mark Raffetto

David T Emerson

Kevin Haberern

Yifeng Wu

Paul M Enquist

Valeri Fedorovich Tsvetkov

Hua-shuang Kong

Van Mieczkowski

John Williams Palmour

Norbert Hiller

Ashay Chitnis

Lori A Lipkin

Amber Christine Salter

Hua Shuang Kong

Ralph C Tuttle

Christopher Sean Plunket

Thomas P Schneider

Helmut Hagleitner

Michael L Lovejoy

Brad Williams

Alexander A Suvorov

David C Craft

Pritish Kar

Ian Hamilton

Benny H Rose

Iain Hamilton

A method of forming an ohmic contact for a semiconductor device can be provided by thinning a substrate to provide a reduced thickness substrate and providing a metal on the reduced thickness substrate. Laser annealing can be performed at a location of the metal and the reduced thickness substrate at an energy level to form a metal-substrate material to provide the ohmic contact thereat.

Localized annealing of metal-silicon carbide ohmic contacts and devices so formed

A light emitting diode is disclosed that includes an active structure formed of at least p-type and n-type epitaxial layers of Group III nitride on a conductive carrier substrate. A conductive bonding system joins the active structure to the conductive carrier substrate. A first transparent ohmic contact is on the active structure adjacent the conductive carrier substrate, a second transparent ohmic contact is on the active structure opposite the conductive carrier substrate, and a third ohmic contact is on the conductive carrier substrate opposite from the active structure.

Transparent ohmic contacts on light emitting diodes with carrier substrates

A light emitting device includes an active layer configured to provide light emission due to carrier recombination therein, a surface on the active layer, and an electrically conductive contact structure on the surface. The contact structure includes at least one plated contact layer. The contact structure may include a sublayer that conforms to the surface roughness of the underlying surface, and the plated contact layer may be substantially free of the surface roughness of the underlying surface. The surface of the plated contact layer may be substantially planar and/or otherwise configured to reflect the light emission from the active layer. Related fabrication methods are also discussed.

Light emitting diode (LED) contact structures and process for fabricating the same

A vertical geometry light emitting diode is disclosed that is capable of emitting light in the red, green, blue, violet and ultraviolet portions of the electromagnetic spectrum. The light emitting diode includes a conductive silicon carbide substrate, an InGaN quantum well, a conductive buffer layer between the substrate and the quantum well, a respective undoped gallium nitride layer on each surface of the quantum well, and ohmic contacts in a vertical geometry orientation.

Vertical geometry InGaN LED

Semiconductor light emitting devices, such as light emitting diodes, include a substrate, an epitaxial region on the substrate that includes a light emitting region such as a light emitting diode region, and a multilayer conductive stack including a current spreading layer, on the epitaxial region. A barrier layer is provided on the current spreading layer and extending on a sidewall of the current spreading layer. The multilayer conductive stack can also include an ohmic layer between the reflector and the epitaxial region. The barrier layer further extends on a sidewall of the ohmic layer. The barrier layer can also extend onto the epitaxial region outside the multilayer conductive stack. The barrier layer can be fabricated as a series of alternating first and second sublayers.

Light emitting diodes including current spreading layer and barrier sublayers

A high efficiency Group III nitride light emitting diode is disclosed. The diode includes a Group III nitride-based light emitting region including a plurality of Group III nitride-based layers. A lenticular surface directly contacts one of the Group III nitride-based layers of the light emitting region. The lenticular surface includes a transparent material that is different from the Group III nitride-based layer of the light emitting region that the lenticular surface directly contacts.

High efficiency group III nitride LED with lenticular surface

A method is disclosed for treating a silicon carbide substrate for improved epitaxial deposition thereon and for use as a precursor in the manufacture of devices such as light emitting diodes. The method includes the steps of implanting dopant atoms of a first conductivity type into the first surface of a conductive silicon carbide wafer having the same conductivity type as the implanting ions at one or more predetermined dopant concentrations and implant energies to form a dopant profile, annealing the implanted wafer, and growing an epitaxial layer on the implanted first surface of the wafer.

Methods of treating a silicon carbide substrate for improved epitaxial deposition and resulting structures and devices

A light emitting device includes a p-type semiconductor layer, an n-type semiconductor layer and an active region between the p-type semiconductor layer and the n-type semiconductor layer. A bond pad is provided on one of the p-type semiconductor layer or the n-type semiconductor layer, opposite the active region, the bond pad being electrically connected to the one of the p-type semiconductor layer or the n-type semiconductor layer. A conductive finger extends from and is electrically connected to the bond pad. A reduced conductivity region is provided in the light emitting device that is aligned with the conductive finger. A reflector may also be provided between the bond pad and the reduced conductivity region. A reduced conductivity region may also be provided in the light emitting device that is not aligned with the bond pad.

Light emitting devices having current reducing structures

A high efficiency Group III nitride light emitting diode is disclosed. The diode includes a substrate selected from the group consisting of semiconducting and conducting materials, a Group III nitride-based light emitting region on or above the substrate, and, a lenticular surface containing silicon carbide on or above the light emitting region, and extending to said light emitting region.

High efficiency Group III nitride LED with lenticular surface

Light emitting diodes include a diode region comprising a gallium nitride-based n-type layer, an active region and a gallium nitride-based p-type layer. A substrate is provided on the gallium nitride-based n-type layer and optically matched to the diode region. The substrate has a first face remote from the gallium nitride-based n-type layer, a second face adjacent the gallium nitride-based n-type layer and a sidewall therebetween. At least a portion of the sidewall is beveled, so as to extend oblique to the first and second faces. A reflector may be provided on the gallium nitride-based p-type layer opposite the substrate. Moreover, the diode region may be wider than the second face of the substrate and may include a mesa remote from the first face that is narrower than the first face and the second face.

Light emitting diodes including optically matched substrates

A semiconductor wafer, substrate, and bonding structure is disclosed that includes a device wafer that includes, for example, a plurality of light emitting diodes, a contact metal layer (or layers) on one side of the device wafer opposite the light emitting diodes, and a bonding metal system on the contact metal layer that predominates by weight in nickel and tin.

Nickel tin bonding system for semiconductor wafers and devices

Semiconductor light emitting devices, such as light emitting diodes, include a substrate, an epitaxial region on the substrate that includes a light emitting region such as a light emitting diode region, and a multilayer conductive stack including a reflector layer, on the epitaxial region. A barrier layer is provided on the reflector layer and extending on a sidewall of the reflector layer. The multilayer conductive stack can also include an ohmic layer between the reflector and the epitaxial region. The barrier layer further extends on a sidewall of the ohmic layer. The barrier layer can also extend onto the epitaxial region outside the multilayer conductive stack. The barrier layer can be fabricated as a series of alternating first and second sublayers.

Light emitting diodes including barrier sublayers

A light emitting diode is disclosed that includes an active region and a plurality of exterior surfaces. 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 and texturing. A light enhancement feature is present on at least portions of each of the other exterior surfaces of the diode, with these light enhancement features being selected from the group consisting of shaping, texturing, and reflectors.

Light emitting diode with improved light extraction

A light emitting device includes a p-type semiconductor layer, an n-type semiconductor layer, and an active region between the n-type semiconductor layer and the p-type semiconductor layer. A non-transparent feature, such as a wire bond pad, is on the p-type semiconductor layer or on the n-type semiconductor layer opposite the p-type semiconductor layer, and a reduced conductivity region is in the p-type semiconductor layer or the n-type semiconductor layer and is aligned with the non-transparent feature. The reduced conductivity region may extend from a surface of the p-type semiconductor layer opposite the n-type semiconductor layer towards the active region and/or from a surface of the n-type semiconductor layer opposite the p-type semiconductor layer towards the active region.

Methods of forming light emitting devices having current reducing structures

A light emitting diode includes a diode region having a gallium nitride based n-type layer, an active region and a gallium nitride based p-type layer. A first reflector layer is provided on the gallium nitride based p-type layer, and a second reflector layer is provided on the gallium nitride based n-type layer. Bonding layers, a mounting support, a wire bond and/or transparent oxide layers also may be provided.

Light emitting diodes including two reflector layers

Growing community of inventors

Raleigh, NC, United States of America

David Beardsley Slater, Jr