Abstract: 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.

Abstract: 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.

Abstract: 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.

Abstract: 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.

Abstract: A microelectronic device includes a GaN FET on a substrate such as silicon and a buffer layer of p-type GaN semiconductor material. The GaN FET includes a gate electrode extension of p-type GaN semiconductor material in electrical contact with the gate electrode. The gate electrode extension of p-type GaN semiconductor material in electrical contact with the gate electrode may improve the GaN FET characteristics such as off state leakage, subthreshold voltage and post stress Vt shift.

Abstract: GaN devices with a modified heterojunction structure and methods of making thereof are described. The GaN device comprises a heterojunction structure modified to include one or more deactivated regions. The heterojunction structure of the deactivated regions has different structural configurations than that of the as-grown heterojunction structure. The locally confined structural alteration of the heterojunction structure weakens or prohibits 2DEG formation in the deactivated regions. Moreover, the amount of net charges mapped to a field plate positioned above the heterojunction structure can be locally reduced or eliminated. Consequently, the electric field present between the heterojunction structure and the field plate can be reduced.

Abstract: 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.

Abstract: 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.

Abstract: A gallium nitride (“GaN”)-based semiconductor device, and method of forming the same. In one example, the semiconductor device includes a channel layer including GaN, and a barrier layer of a first III-N material over the channel layer. The semiconductor device also includes a cap layer of a second III-N material including indium over the barrier layer, wherein the cap layer may have the effect of modifying a threshold voltage and gate leakage current of the semiconductor device.

Abstract: One example described herein includes an integrated circuit (IC) that includes a gallium-nitride (GaN) transistor device. The IC includes GaN active layers that define an active region, and a gate structure arranged on a surface of the active region. The IC also includes a source arranged on a first side of the gate structure and a drain arranged on a second side of the gate structure. The IC further includes at least one source field-plate structure conductively coupled to the source and a gate-level field-plate structure that is coupled to the source.

Abstract: A depletion-mode current source having a saturation current of sufficient accuracy for use as a pre-charge circuit in a start-up circuit of an AC-to-DC power converter is fabricated using an enhancement-mode-only process. The depletion-mode current source can be fabricated on the same integrated circuit (IC) as a gallium nitride field-effect transistor (FET) and resistive and capacitive components used in the start-up circuit, without affecting the enhancement-mode-only fabrication process by requiring additional masks or materials, as would be required to fabricate a depletion-mode FET on the same IC as an enhancement-mode FET. The current source includes a resistive patterned two-dimensional electron gas (2DEG) or two-dimensional hole gas (2DHG) channel coupled between two terminals and one or more metal field plates extending from one of the terminals and overlying the patterned area of the channel, the field plates being separated from the channel and from each other by dielectric layers.

Abstract: 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.

Abstract: 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 (2 DEG). 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.

Abstract: Fabrication methods, electronic devices and enhancement mode gallium nitride transistors include a gallium nitride interlayer between a hetero-epitaxy structure and a p-doped gallium nitride layer and/or between the p-doped gallium nitride layer and a gate structure to mitigate p-type dopant diffusion, improve current collapse performance, and mitigate positive-bias temperature instability. In certain examples, the interlayer or interlayers is/are fabricated using epitaxial deposition with no p-type dopant source. In certain fabrication process examples, epitaxial deposition or growth is interrupted after the depositing an aluminum gallium nitride layer of the hetero-epitaxy structure, after which growth is resumed to deposit the first gallium nitride interlayer over the aluminum gallium nitride layer to mitigate p-type dopant diffusion and current collapse.

Abstract: 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.

Abstract: 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.

Abstract: 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.

Abstract: 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.

Abstract: 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.

Abstract: 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.