Texas Instruments Corporation

Transphorm Inc.

University of California

Tansphorm Inc.

Chang Soo Suh

Jungwoo Joh

Umesh Kumar Mishra

Sameer P Pendharkar

Naveen Tipirneni

Dong Seup Lee

Ilan Ben-Yaacov

James Stephen Speck

Qhalid Fareed

Robert Coffie

Karen Hildegard Ralston Kirmse

Ramana Tadepalli

Siddharth Rajan

Shoji Wada

Sridhar Seetharaman

In some examples, a gallium nitride (GaN)-based transistor, comprises a substrate; a GaN layer supported by the substrate; an aluminum nitride gallium (AlGaN) layer supported by the GaN layer; a p-doped GaN structure supported by the AlGaN layer; and multiple p-doped GaN blocks supported by the AlGaN layer, each of the multiple p-doped GaN blocks physically separated from the remaining multiple p-doped GaN blocks, wherein first and second contours of a two-dimensional electron gas (2DEG) of the GaN-based transistor are at an interface of the AlGaN and GaN layers.

Gallium nitride (GaN) based transistor with multiple p-GaN blocks

A semiconductor device includes a gallium nitride based low threshold depletion mode transistor (GaN FET) with a threshold potential between −10 volts and −0.5 volts. The GaN FET has a channel layer of III-N semiconductor material including gallium and nitrogen that supports a two-dimensional electron gas (2DEG). The GaN FET has a barrier layer of III-N semiconductor material including aluminum and nitrogen over the channel layer. The GaN FET further has a p-type gate of III-N semiconductor material including gallium and nitrogen. A bottom surface of the gate, adjacent to the barrier layer, does not extend past a top surface of the barrier layer, located opposite from the channel layer. The GaN FET is free of a dielectric layer between the gate and the barrier layer.

Normally-on gallium nitride based transistor with p-type gate

An electronic device includes an one of aluminum gallium nitride, aluminum nitride, indium aluminum nitride, or indium aluminum gallium nitride back barrier layer over a buffer structure, a gallium nitride layer over the back barrier layer, a hetero-epitaxy structure over the gallium nitride layer, first and second transistors over the hetero-epitaxy structure, and a hole injector having a doped gallium nitride structure over the hetero-epitaxy structure and a conductive structure partially over the doped gallium nitride structure to inject holes to form a hole layer proximate an interface of the back barrier layer and the buffer structure to mitigate vertical electric field back gating effects for the first transistor.

Monolithic integration of high and low-side GaN FETs with screening back gating effect

In a described example, an apparatus includes a transistor formed on a semiconductor substrate, the transistor including: a transistor gate and an extended drain between the transistor gate and a transistor drain contact; a transistor source contact coupled to a source contact probe pad; a first dielectric layer covering the semiconductor substrate and the transistor gate; a source field plate on the first dielectric layer and coupled to a source field plate probe pad spaced from and electrically isolated from the source contact probe pad; and the source field plate capacitively coupled through the first dielectric layer to a first portion of the extended drain.

Method for testing a high voltage transistor with a field plate

A High Electron Mobility Transistor (HEMT) includes an active layer on a substrate, and a Group IIIA-N barrier layer on the active layer. An isolation region is through the barrier layer to provide at least one isolated active area including the barrier layer on the active layer. A gate is over the barrier layer. A drain includes at least one drain finger including a fingertip having a drain contact extending into the barrier layer to contact to the active layer and a source having a source contact extending into the barrier layer to contact to the active layer. The source forms a loop that encircles the drain. The isolation region includes a portion positioned between the source and drain contact so that there is a conduction barrier in a length direction between the drain contact of the fingertip and the source.

HEMT having conduction barrier between drain fingertip and source

One example provides an enhancement-mode High Electron Mobility Transistor (HEMT) includes a substrate, a Group IIIA-N active layer over the substrate, a Group IIIA-N barrier layer over the active layer, and at least one isolation region through the barrier layer to provide an isolated active area having the barrier layer on the active layer. A gate stack is located between source and drain contacts to the active layer. A tunnel diode in the gate stack includes an n-GaN layer on an InGaN layer on a p-GaN layer located on the barrier layer.

Group IIIA-N HEMT with a tunnel diode in the gate stack

An enhancement-mode High Electron Mobility Transistor (HEMT) includes a substrate, a Group IIIA-N active layer on the substrate, a Group IIIA-N barrier layer on the active layer, and at least one isolation region through the barrier layer to provide an isolated active area having the barrier layer on the active layer. A p-GaN layer is on the barrier layer. A tunnel diode in the gate stack includes an n-GaN layer on an InGaN layer on the p-GaN layer. A gate electrode is over the n-GaN layer. A drain having a drain contact is on the barrier layer to provide contact to the active layer, and a source having a source contact is on the barrier layer provides contact to the active layer. The tunnel diode provides a gate contact to eliminate the need to form a gate contact directly to the p-GaN layer.

Enhancement mode III-nitride devices are described. The 2DEG is depleted in the gate region so that the device is unable to conduct current when no bias is applied at the gate. Both gallium face and nitride face devices formed as enhancement mode devices.

Gallium nitride power devices

Enhancement mode gallium nitride power devices

A novel enhancement mode field effect transistor (FET), such as a High Electron Mobility Transistors (HEMT), has an N-polar surface uses polarization fields to reduce the electron population under the gate in the N-polar orientation, has improved dispersion suppression, and low gate leakage.

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Allen, TX, United States of America

Chang Soo Suh