International Rectifier Corporation

Nitronex Corporation

Cree Gmbh

Infineon Technologies Americas Corp.

Macom Technology Solutions Holdings, Inc.

T Warren Weeks, Jr

Thomas Gehrke

Kevin J Linthicum

Edwin Lanier Piner

Cem Basceri

Christopher Harris

Ricardo M Borges

Elif Berkman

Kevin M Linthicum

A semiconductor material includes a compositionally-graded transition layer, an intermediate later and a gallium nitride material layer. The compositionally-graded transition layer has a back surface and a top surface, and includes a gallium nitride alloy. The gallium concentration in the compositionally-graded transition layer increases from the back surface to the front surface. The intermediate layer is formed under the compositionally-graded transition layer. The gallium nitride material layer is formed over the compositionally-graded transition layer, and has a crack level of less than 0.005 &#x3bc;m/&#x3bc;m.

Semiconductor material having a compositionally-graded transition layer

The invention provides semiconductor materials including a gallium nitride material layer formed on a silicon substrate and methods to form the semiconductor materials. The semiconductor materials include a transition layer formed between the silicon substrate and the gallium nitride material layer. The transition layer is compositionally-graded to lower stresses in the gallium nitride material layer which can result from differences in thermal expansion rates between the gallium nitride material and the substrate. The lowering of stresses in the gallium nitride material layer reduces the tendency of cracks to form. Thus, the invention enables the production of semiconductor materials including gallium nitride material layers having few or no cracks. The semiconductor materials may be used in a number of microelectronic and optical applications.

Semiconductor structure with compositionally-graded transition layer

Gallium nitride devices with discontinuously graded transition layer

III-nitride based semiconductor structure

Gallium nitride semiconductor structures with compositionally-graded transition layer

Gallium nitride devices with aluminum nitride intermediate layer

Gallium nitride devices with aluminum nitride alloy intermediate layer

Gallium nitride devices with gallium nitride alloy intermediate layer

Gallium nitride semiconductor structures with compositionally-graded  transition layer

Gallium nitride materials and methods

A method of compensating resistivity of a near-surface region of a substrate includes epitaxially growing a buffer layer on the substrate, wherein the buffer is grown as having a dopant concentration as dependent on resistivity and conductivity of the substrate, so as to deplete residual or excess charge within the near-surface region of the substrate. The dopant profile of the buffer layer be smoothly graded, or may consist of sub-layers of different dopant concentration, to also provide a highly resistive upper portion of the buffer layer ideal for subsequent device growth. Also, the buffer layer may be doped with carbon, and aluminum may be used to getter the carbon during epitaxial growth.

Method of manufacturing an adaptive AIGaN buffer layer

A method of manufacturing a heterojunction device includes forming a first layer of p-type aluminum gallium nitride; forming a second layer of undoped gallium nitride on the first layer; and forming a third layer of aluminum gallium nitride on the second layer, to provide an electron gas between the second and third layers. A heterojunction between the first and second layers injects positive charge into the second layer to compensate and/or neutralize negative charge within the electron gas.

Method of manufacturing gallium nitride based high-electron mobility devices

A heterojunction device includes a first layer of p-type aluminum gallium nitride; a second layer of undoped gallium nitride on the first layer; a third layer of aluminum gallium nitride on the second layer; and an electron gas between the second and third layers. A heterojunction between the first and second layers injects positive charge into the second layer to compensate and/or neutralize negative charge within the electron gas.

Gallium nitride based high-electron mobility devices

The invention provides gallium nitride material devices, structures and methods of forming the same. The devices include a gallium nitride material formed over a substrate, such as silicon. Exemplary devices include light emitting devices (e.g., LED's, lasers), light detecting devices (such as detectors and sensors), power rectifier diodes and FETs (e.g., HFETs), amongst others.

Gallium nitride material devices and methods of forming the same

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Raleigh, NC, United States of America

T Warren Weeks, Jr