Wolfspeed, Inc.

Semiconductor Components Industries, LLC

Macom Technology Solutions Holdings, Inc.

Cree Gmbh

Jia Guo

Scott Thomas Sheppard

Kyle Bothe

Saptharishi Sriram

Fabian Radulescu

Jeremy Fisher

Peter Moens

Qianli Mu

Terry Alcorn

Ali Salih

Chun-Li Liu

Zulhazmi Mokhti

Yueying Liu

Matt King

Dan Namishia

Kyoung-Keun Lee

Chris Hardiman

Evan Jones

Elizabeth Keenan

An apparatus to address gate lag effect and/or other negative performance includes a substrate; a group III-Nitride buffer layer on the substrate; a group III-Nitride barrier layer on the group III-Nitride buffer layer, the group III-Nitride barrier layer may include a higher bandgap than a bandgap of the group III-Nitride buffer layer; a source electrically coupled to the group III-Nitride barrier layer; a gate electrically coupled to the group III-Nitride barrier layer; a drain electrically coupled to the group III-Nitride barrier layer; and a p-region being arranged at least in the substrate. In particular, the p-region extends toward a source side of the substrate; and the p-region extends toward a drain side of the substrate.

Group III-nitride high-electron mobility transistors with gate connected buried p-type layers and process for making the same

A high electron mobility transistor comprises a semiconductor layer structure that includes a channel layer and a barrier layer and source and drain contacts on the semiconductor layer structure. A gate contact and a multi-layer passivation structure are provided on the semiconductor layer structure between the source contact and the drain contact. The multi-layer passivation structure comprises at least first and second silicon nitride layers that have different material compositions. A spacer passivation layer is provided on sidewalls of the first and second silicon nitride layers. A material composition of the spacer passivation layer is different than a material composition of at least one of the layers of the multi-layer passivation structure.

High electron mobility transistors having reduced drain current drift and methods of fabricating such devices

A transistor includes a first passivation layer on a semiconductor layer of the transistor between a source contact and a drain contact. The first passivation layer includes a portion having a topological change. The transistor further includes a discontinuous barrier layer on the portion of the first passivation layer having the topological change. The discontinuous barrier layer is configured to reduce ingress of moisture in the portion of the first passivation layer.

Transistor including a discontinuous barrier layer

A transistor device includes a first unit subcell including having a first active region width extending in a first direction, and a second unit subcell having a second active region width extending in the first direction and arranged adjacent the first unit subcell in the first direction. The first unit subcell and the second unit subcell share a common drain contact and have separate gate contacts that are aligned in the first direction. Each unit subcell includes a field plate that is connected to a source contact outside the active region and that does not cross over the gate contact.

Field effect transistor with stacked unit subcell structure

A transistor device according to some embodiments includes a channel layer, a barrier layer on the channel layer, and source and drain contacts on the barrier layer, and a gate contact on the barrier layer between the source and drain contacts. The channel layer includes a sub-layer having an increased doping concentration level relative to a remaining portion of the channel layer. The presence of the sub-layer may reduce drain lag without substantially increasing gate lag.

Field effect transistor with selective channel layer doping

A transistor device according to some embodiments includes a semiconductor barrier layer, a surface dielectric layer on the semiconductor barrier layer, and a gate on the surface dielectric layer. The surface dielectric layer includes an aperture therein that is laterally spaced apart from the gate. The device includes an interlayer dielectric layer on the surface dielectric layer that extends over the gate and into the aperture in the surface dielectric layer, and a multiple-stepped field plate on the interlayer dielectric layer. The multiple-stepped field plate is laterally spaced apart from the gate. A recessed portion of the multiple-stepped field plate is above the aperture in the surface dielectric layer, and the multiple-stepped field plate includes a first step adjacent the recessed portion of the field plate on a side of the field plate opposite the gate, and a second step adjacent the first step.

Field effect transistor with multiple stepped field plate

A gallium nitride-based RF transistor amplifier comprises a semiconductor layer structure comprising a barrier layer on a channel layer, first and second source/drain regions in the semiconductor layer structure, first and second source/drain contacts on the respective first and second source/drain regions, and a longitudinally-extending gate finger that is between the first and second source/drain contacts. The first and second source/drain contacts each has an inner sidewall that faces the gate finger and an opposed outer sidewall. The first source/drain region extends a first distance from a lower edge of the inner sidewall of the first source/drain contact towards the second source/drain region along a transverse axis that extends parallel to a plane defined by the upper surface of the semiconductor layer structure, and extends a second, smaller distance from a lower edge of the outer sidewall of the first source/drain contact away from the second source/drain region.

Radio frequency transistor amplifiers having widened and/or asymmetric source/drain regions for improved on-resistance performance

A transistor device includes a semiconductor layer, source and drain contacts on the semiconductor layer, a gate contact on the semiconductor layer between the source and drain contacts, and a field plate over the semiconductor layer between the gate contact and the drain contact. The transistor device includes a first electrical connection between the field plate and the source contact that is outside an active region of the transistor device, and a second electrical connection between the field plate and the source contact.

Field effect transistor with source-connected field plate

A transistor device includes a semiconductor epitaxial layer structure including a channel layer and a barrier layer on the channel layer, a source contact and a drain contact on the barrier layer, an insulating layer on the semiconductor layer between the source contact and the drain contact, and a gate contact on the insulating layer. The gate contact includes a central portion that extends through the insulating layer and contacts the barrier layer and a drain side wing that extends laterally from the central portion of the gate toward the drain contact by a distance &#x393;. The drain side wing of the gate contact is spaced apart from the barrier layer by a distance dthat is equal to a thickness of the insulating layer. The distance &#x393;is less than about 0.3 &#x3bc;m, and the distance dis less than about 80 nm.

Field effect transistor with enhanced reliability

Gallium nitride based RF transistor amplifiers include a semiconductor structure having a gallium nitride based channel layer and a gallium nitride based barrier layer thereon, and are configured to operate at a specific direct current drain-to-source bias voltage. These amplifiers are configured to have a normalized drain-to-gate capacitance at the direct current drain-to-source bias voltage, and to have a second normalized drain-to-gate capacitance at two-thirds the direct current drain-to-source bias voltage, where the second normalized drain-to-gate capacitance is less than twice the first normalized drain-to-gate capacitance.

Radio frequency transistor amplifiers having engineered intrinsic capacitances for improved performance

A transistor device includes a semiconductor layer, a surface dielectric layer on the semiconductor layer, and at least a portion of a gate on the surface dielectric layer. The surface dielectric layer includes an aperture therein that is laterally spaced apart from the gate. The transistor device includes an interlayer dielectric layer on the surface dielectric layer, and a field plate on the interlayer dielectric layer. The field plate is laterally spaced apart from the gate, and at least a portion of the field plate includes a recessed portion above the aperture in the surface dielectric layer.

Field effect transistor with at least partially recessed field plate

A device includes a substrate; a buffer layer on the substrate; a barrier layer on the buffer layer, a source electrically coupled to the barrier layer; a gate electrically coupled to the barrier layer; and a drain electrically coupled to the barrier layer. The device further includes an electron concentration reduction structure arranged with at least one of the following: in the barrier layer and on the barrier layer. The electron concentration reduction structure is configured to at least one of the following: reduce electron concentration around the gate, reduce electron concentration around an edge of the gate, reduce electron concentration, increase power gain, increase efficiency, decouple the gate from the drain, decouple the gate from the source, and reduce capacitance.

Structures for reducing electron concentration and process for reducing electron concentration

Radio frequency transistor amplifiers having engineered instrinsic capacitances for improved performance

A transistor includes a semiconductor layer structure, a source electrode and a drain electrode on the semiconductor layer structure, a gate on a surface of the semiconductor layer structure between the source electrode and the drain electrode, and a field plate. The field plate includes a first portion adjacent the gate and a second portion adjacent the source or drain electrode. The second portion of the field plate is farther from the surface of the semiconductor layer structure than the first portion of the field plate, and is closer to the surface of the semiconductor layer structure than an extended portion of the gate. Related devices and fabrication methods are also discussed.

Stepped field plates with proximity to conduction channel and related fabrication methods

An electronic device can include a HEMT including at least two channel layers. In an embodiment, a lower semiconductor layer overlies a lower channel layer, wherein the lower semiconductor layer has an aluminum content that is at least 10% of a total metal content of the lower semiconductor layer. An upper semiconductor layer overlies the upper channel layer, wherein the upper semiconductor layer has an aluminum content that is greater as compared to the lower semiconductor layer. In another embodiment, an electronic device can include stepped source and drain electrodes, so that lower contact resistance can be achieved. In a further embodiment, an absolute value of a difference between pinch-off or threshold voltages between different channel layers is greater than 1 V and allows current to be turned on or turned off for a channel layer without affecting another channel layer.

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Durham, NC, United States of America

Jia Guo