Cree Gmbh

Cree Microwave, Inc.

Nextreme Thermal Solutions, Inc.

Jayesh Bharathan

John Adam Edmond

David Beardsley Slater, Jr

Mark Raffetto

Gerald H Negley

Peter Scott Andrews

Matthew Donofrio

Anwar Mohammed

James Ibbetson

David T Emerson

Michael John Bergmann

Kevin Haberern

Ting Li

Bernd P Keller

Scott Thomas Allen

Rama Venkatasubramanian

Bing A Shen

David Alan Koester

Bradley E Williams

Pratima V Addepalli

Randall G Alley

Cynthia Watkins

David Slater

Jr David B Slater

David Beardsley Slater

A light emitter includes a planar supporting surface, a light source positioned on the spreader region, and an encapsulant positioned on the spreader region to surround the light source. Except where constrained by adhesion to the planar supporting surface, the encapsulant is capable of expanding and contracting in response to a change in temperature so that forces caused by differences in the coefficient of thermal expansion between the different components is minimized. One or more reflective elements can be positioned proximate to the light source to increase the light emitting efficiency of the light emitter. The reflective elements can include a reflective layer on the spreader region and/or a reflective layer on a portion of the encapsulant.

High powered light emitter packages with compact optics

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 flip-chip semiconductor based Light Emitting Device (LED) can include an n-type semiconductor substrate and an n-type GaN epi-layer on the substrate. A p-type GaN epi-layer can be on the n-type GaN epi-layer and a metal ohmic contact p-electrode can be on the p-type GaN epi-layer, where the metal ohmic contact p-electrode can have an average thickness less than about 25 &#x212b;. A reflector can be on the metal ohmic contact p-electrode and a metal stack can be on the reflector. An n-electrode can be on the substrate opposite the n-type GaN epi-layer and a bonding pad can be on the n-electrode.

Ultra-thin ohmic contacts for p-type nitride light emitting devices

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

A light emitting diode is disclosed that includes a conductive substrate, a bonding metal on the conductive substrate and a barrier metal layer on the bonding metal. A mirror layer is encapsulated by the barrier metal layer and is isolated from the bonding metal by the barrier layer. A p-type gallium nitride epitaxial layer is on the encapsulated mirror, an indium gallium nitride active layer is on the p-type layer, and an n-type gallium nitride layer is on the indium gallium nitride layer, and a bond pad is made to the n-type gallium nitride layer.

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.

A light emitting diode is disclosed having a vertical orientation with an ohmic contact on portions of a top surface of the diode and a mirror layer adjacent the light emitting region of the diode. The diode includes an opening in the mirror layer beneath the geometric projection of the top ohmic contact through the diode that defines a non-contact area between the mirror layer and the light emitting region of the diode to encourage current flow to take place other than at the non-contact area to in turn decrease the number of light emitting recombinations beneath the ohmic contact and increase the number of light emitting recombinations in the more transparent portions of the diode.

A semiconductor based Light Emitting Device (LED) can include a p-type nitride layer and a metal ohmic contact, on the p-type nitride layer. The metal ohmic contact can have an average thickness of less than about 25 &#x212b; and a specific contact resistivity less than about 10ohm-cm.

A method of forming a thermoelectric device may include forming a plurality of islands of thermoelectric material on a deposition substrate. The plurality of islands of thermoelectric material may be bonded to a header substrate so that the plurality of islands are between the deposition substrate and the header substrate. More particularly, the islands of thermoelectric material may be epitaxial islands of thermoelectric material having crystal structures aligned with a crystal structure of the deposition substrate. Related structures are also discussed.

Methods of forming thermoelectric devices using islands of thermoelectric material and related structures

Light emitting device die having a mesa configuration on a substrate and an electrode on the mesa are attached to a submount in a flip-chip configuration by forming predefined pattern of conductive die attach material on at least one of the electrode and the submount and mounting the light emitting device die to the submount. The predefined pattern of conductive die attach material is selected so as to prevent the conductive die attach material from contacting regions of having opposite conductivity types when the light emitting device die is mounted to the submount. The predefined pattern of conductive die attach material may provide a volume of die attach material that is less than a volume defined by an area of the electrode and a distance between the electrode and the submount. Light emitting device dies having predefined patterns of conductive die attach material are also provided. Light emitting devices having a gallium nitride based light emitting region on a substrate, such as a silicon carbide substrate, may also be mounted in a flip-chip configuration by mounting an electrode of the gallium nitride based light emitting region to a submount utilizing a B-stage curable die epoxy. Light emitting device dies having a B-stage curable die epoxy are also provided.

Light emitting devices suitable for flip-chip bonding

Bonding of flip-chip mounted light emitting devices having an irregular configuration is provided. Light emitting diodes having a shaped substrate are bonded to a submount by applying forces to the substrate an a manner such that shear forces within the substrate do not exceed a failure threshold of the substrate. Bonding a light emitting diode to a submount may be provided by applying force to a surface of a substrate of the light emitting diode that is oblique to a direction of motion of the light emitting diode to thermosonically bond the light emitting diode to the submount. Collets for use in bonding shaped substrates to a submount and systems for bonding shaped substrates to a submount are also provided.

Bonding of light emitting diodes having shaped substrates

Flip-chip bonding of light emitting devices

A method and resulting structures are disclosed for fabricating a high efficiency high extraction light emitting diode suitable for packaging. The method includes the steps of adding a light emitting active portion of wide-bandgap semiconductor material to a conductive silicon carbide substrate, joining the added active portion to a conductive sub-mounting structure, and removing a portion of the silicon carbide substrate opposite the added active portion to thereby reduce the overall thickness of the joined substrate, active portion and sub-mounting structure. The resulting the sub-mounting structure can be joined to a lead frame with the active portion positioned between the silicon carbide substrate and the sub-mounting structure to thereby use the sub-mounting structure to separate the active portion from the lead frame and avoid undesired electrical contact between the active portion and the lead frame.

Growing community of inventors

Cary, NC, United States of America

Jayesh Bharathan