Power Integrations, Inc.

Velox Semiconductor Corporation

Veeco Instruments Inc.

Emcore Corporation

Michael Murphy

Milan Pophristic

Bryan S Shelton

LinLin Liu

Richard A Stall

Alex D Ceruzzi

Jamal Ramdani

John Paul Edwards

Ivan Eliashevich

Eric Armour

Mark Gottfried

Boris Peres

Jeffrey C Ramer

Marek Pabisz

Richard Hoffman

Jonathan Cruel

TingGang Zhu

Lev Kadinski

Xiang Gao

Ting Gang Zhu

Shiping Guo

David Gotthold

Linlin c/o Velox Semiconductor Corp Liu

Milan c/o Velox Semiconductor Corp Pophristic

Ting Gang c/o Velox Semiconductor Corp Zhu

A heterostructure semiconductor device includes a first active layer and a second active layer disposed on the first active layer. A two-dimensional electron gas layer is formed between the first and second active layers. An AlSiN passivation layer is disposed on the second active layer. First and second ohmic contacts electrically connect to the second active layer. The first and second ohmic contacts are laterally spaced-apart, with a gate being disposed between the first and second ohmic contacts.

Heterostructure power transistor with AlSiN passivation layer

In a rotating disk reactor for growing epitaxial layers on substrate or other CVD reactor system, gas directed toward the substrates at gas inlets at different radial distances from the axis of rotation of the disk has both substantially the same gas flow rate/velocity and substantially the same gas density at each inlet. The gas directed toward portions of the disk remote from the axis may include a higher concentration of a reactant gas than the gas directed toward portions of the disk close to the axis, so that portions of the substrate surfaces at different distances from the axis receive substantially the same amount of reactant gas per unit area, and a combination of carrier gases with different relative molecular weights at different radial distances from the axis of rotation are employed to substantially make equal the gas density in each region of the reactor. The system may be applied with a combination or carrier gases at multiple gas inlets, a combination of carrier and reactant gases at multiple inlets, and may be used with an arbitrarily large number of gases, when at least two gases of different molecular weights are provided. A linear flow pattern is achieved within the reactor, avoiding laminar recirculation areas, and permitting uniform deposition and growth of epitaxial layers on the substrate.

Alkyl push flow for vertical flow rotating disk reactors

In a rotating disk reactor () for growing epitaxial layers on substrate (), gas directed toward the substrates at different radial distances from the axis of rotation of the disk has substantially the same velocity. The gas directed toward portions of the disk remote from the axis () may include a higher concentration of a reactant gas () than the gas directed toward portions of the disk close to the axis (), so that portions of the substrate surfaces at different distances from the axis () receive substantially the same amount of reactant gas () per unit area. A desirable flow pattern is achieved within the reactor while permitting uniform deposition and growth of epitaxial layers on the substrate.

A semiconductor device is provided that includes a substrate, a first active layer disposed over the substrate, and a second active layer disposed on the first active layer. The second active layer has a higher bandgap than the first active layer such that a two-dimensional electron gas layer arises between the first active layer and the second active layer. A termination layer, which is disposed on the second active layer, includes InGaN. Source, gate and drain contacts are disposed on the termination layer.

Termination and contact structures for a high voltage GaN-based heterojunction transistor

A gallium nitride based semiconductor Schottky diode fabricated from a n+ doped GaN layer having a thickness between one and six microns disposed on a sapphire substrate; an n&#x2212; doped GaN layer having a thickness greater than one micron disposed on said n+ GaN layer patterned into a plurality of elongated fingers and a metal layer disposed on the n&#x2212; doped GaN layer and forming a Schottky junction therewith. The layer thicknesses and the length and width of the elongated fingers are optimized to achieve a device with breakdown voltage of greater than 500 volts, current capacity in excess of one ampere, and a forward voltage of less than three volts.

Gallium nitride semiconductor device

A circuit includes an input drain, source and gate nodes. The circuit also includes a group III nitride depletion mode FET having a source, drain and gate, wherein the gate of the depletion mode FET is coupled to a potential that maintains the depletion mode FET in its on-state. In addition, the circuit further includes an enhancement mode FET having a source, drain and gate. The source of the depletion mode FET is serially coupled to the drain of the enhancement mode FET. The drain of the depletion mode FET serves as the input drain node, the source of the enhancement mode FET serves as the input source node and the gate of the enhancement mode FET serves as the input gate node.

Cascode circuit employing a depletion-mode, GaN-based FET

A repeatable and uniform low doped layer is formed using modulation doping by forming alternating sub-layers of doped and undoped nitride semiconductor material atop another layer. A Schottky diode is formed of such a low doped nitride semiconductor layer disposed atop a much more highly doped nitride semiconductor layer. The resulting device has both a low on-resistance when the device is forward biased and a high breakdown voltage when the device is reverse biased.

Low doped layer for nitride-based semiconductor device

A guard ring is formed in a semiconductor region that is part of a Schottky junction or Schottky diode. The guard ring is formed by ion implantation into the semiconductor contact layer without completely annealing the semiconductor contact layer to form a high resistance region. The guard ring may be located at the edge of the layer or, alternatively, at a distance away from the edge of the layer. A Schottky metal contact is formed atop the layer, and the edges of the Schottky contact are disposed atop the guard ring.

Non-activated guard ring for semiconductor devices

A nitride semiconductor is grown on a silicon substrate by depositing a few mono-layers of aluminum to protect the silicon substrate from ammonia used during the growth process, and then forming a nucleation layer from aluminum nitride and a buffer structure including multiple superlattices of AlGaN semiconductors having different compositions and an intermediate layer of GaN or other Ga-rich nitride semiconductor. The resulting structure has superior crystal quality. The silicon substrate used in epitaxial growth is removed before completion of the device so as to provide superior electrical properties in devices such as high-electron mobility transistors.

Semiconductor structures for gallium nitride-based devices

A lateral conduction Schottky diode includes multiple mesa regions upon which Schottky contacts are formed and which are at least separated by ohmic contacts to reduce the current path length and reduce current crowding in the Schottky contact, thereby reducing the forward resistance of a device. The multiple mesas may be isolated from one another and have sizes and shapes optimized for reducing the forward resistance. Alternatively, some of the mesas may be finger-shaped and intersect with a central mesa or a bridge mesa, and some or all of the ohmic contacts are interdigitated with the finger-shaped mesas. The dimensions of the finger-shaped mesas and the perimeter of the intersecting structure may be optimized to reduce the forward resistance. The Schottky diodes may be mounted to a submount in a flip chip arrangement that further reduces the forward voltage as well as improves power dissertation and reduces heat generation.

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Somerset, NJ, United States of America

Michael Murphy