Lumileds Lighting U.s., LLC

University of Illinois

Philips Lumileds Lighting Company LLC

Steven A Maranowski

Fred A Kish, Jr

Daniel Alexander Steigerwald

Nick Holonyak, Jr

Michael Joseph Ludowise

Serge Laurent Rudaz

Paul Scott Martin

Steven D Lester

Jerome Chandra Bhat

Jonathan J Wierer, Jr

Andrew Kim

William R Imler

Robert M Fletcher

Fred A Kish

Kyle J Thomas

Nick Holonyak

A III-nitride light emitting device is grown on a textured substrate, in order to reduce the amount of total internal reflection at the interface between the substrate and the III-nitride layers. In some embodiments, the device includes a first growth region substantially free of voids, and a second growth region that improves the material quality such that high quality layers can be grown over the first and second regions.

Growth of III-nitride light emitting devices on textured substrates

Silver electrode metallization in light emitting devices is subject to electrochemical migration in the presence of moisture and an electric field. Electrochemical migration of the silver metallization to the pn junction of the device results in an alternate shunt path across the junction, which degrades efficiency of the device. In accordance with a form of this invention, a migration barrier is provided for preventing migration of metal from at least one of the electrodes onto the surface of the semiconductor layer with which the electrode is in contact.

Light emitting semiconductor method and device

A light emitting device includes a heterojunction having a p-type layer and an n-type layer. The n-electrode is electrically connected to the n-type layer while the p-electrode is electrically connected to the p-type layer. The p and n-electrodes are positioned to form a region having uniform light intensity.

Electrode structures for light emitting devices

A method of forming a light-transmissive contact on a p-type Gallium nitride (GaN) layer of an optoelectronic device includes in one embodiment, introducing a selected metal in an oxidized condition, rather than oxidizing the metal only after it has been deposited on the surface of the p-type GaN layer. In some applications, the oxidized metal provides sufficient lateral conductivity to eliminate the conventional requirement of a second highly conductive contact metal, such as gold. If the second contact metal is desired, an anneal in an oxygen-free environment is performed after deposition of the second layer. The anneal causes the second metal to penetrate the oxidized metal and to fuse to the surface of the p-type GaN layer. In a second embodiment, the oxidation occurs only after at least one of the two metals is deposited on the surface of the p-type GaN layer. In one application of the second embodiment, the two metals are deposited and the oxidation occurs in an environment that includes both water vapor and oxygen gas. In an alternative application of the second embodiment, the first metallic layer is deposited and then oxidized throughout its depth. The second material, such as gold, is evaporated on the first material and a re-anneal step is performed to drive the second metal through the oxidized first metal. In any of the applications of either embodiment, a pattern of windows may be formed in the resulting contact structure or in additional layers that are formed thereon.

Method of forming transparent contacts to a p-type GaN layer

A semiconductor laser device includes, in a disclosed embodiment: a semiconductor active region disposed between upper and lower confining regions of opposite type semiconductor material; reflective facets at opposing edges of the active and confining regions; at least one of the confining regions including a layer of relatively high aluminum fraction aluminum-bearing III-V material between layers of relatively low aluminum fraction aluminum bearing III-V material, the layer of relatively high aluminum fraction material having, at its edges and adjacent the facets, spikes of native oxide of aluminum; and electrodes for applying electric potential across the upper and lower confining regions.

Semiconductor devices and methods

By implementing oxidation to obtain a native oxide of aluminum (581,582) after a device has been metallized (505,565), advantages can be obtained in device operation, reliability, and life. A method of making a semiconductor device is disclosed and includes the following steps: forming a structure comprising layers of III-V semiconductor material, at least one of the layers being an aluminum-beating III-V semiconductor material (530,550); applying metal electrodes (505,565) to the structure to form a medalist semiconductor structure; and heating the medalist structure in a water-containing environment to convert a portion of the aluminum-bearing III-V semiconductor material to a native oxide of aluminum (581,582).

Method of fabricating a semiconductor device by oxidizing

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San Jose, CA, United States of America

Steven A Maranowski