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: A semiconductor device is described herein. The semiconductor device comprises a silicon substrate layer. The semiconductor device comprises a first semiconductor layer comprising a gallium nitride layer, the first semiconductor layer disposed over the silicon substrate layer. The semiconductor device comprises a second semiconductor layer disposed on the first semiconductor layer, the second semiconductor layer comprising an aluminum gallium nitride layer. The semiconductor device comprises a first drain contact extending through the second semiconductor layer and extending into the first semiconductor layer.

Abstract: In some examples, a transistor comprises a gallium nitride (GaN) layer; a GaN-based alloy layer having a top side and disposed on the GaN layer, wherein source, drain, and gate contact structures are supported by the GaN layer; and a first doped region positioned in a drain access region and extending from the top side into the GaN layer.

Abstract: The present disclosure generally relates to a resistor structure having a charge control layer. In an example, an integrated circuit includes a semiconductor substrate, a dielectric layer, a first contact, a second contact, and a charge control layer. The semiconductor substrate includes a semiconductor hetero-structure. The dielectric layer is disposed over the semiconductor substrate. The first contact is disposed through the dielectric layer and contacting the semiconductor hetero-structure. The second contact is disposed through the dielectric layer and contacting the semiconductor hetero-structure. The second contact is disposed laterally separated from the first contact. The charge control layer is disposed over the semiconductor hetero-structure and laterally between the first contact and the second contact. At least a portion of the dielectric layer is disposed between the charge control layer and the semiconductor hetero-structure.

Abstract: Fabrication methods and gallium nitride transistors, in which an electronic device includes a substrate, a buffer structure, a hetero-epitaxy structure over the buffer structure, and a transistor over or in the hetero-epitaxy structure. In one example, the buffer structure has an extrinsically carbon doped gallium nitride layer over a dual superlattice stack or over a multilayer composition graded aluminum gallium nitride stack, and a silicon nitride cap layer over the hetero-epitaxy structure.

Abstract: In some examples, a transistor comprises a gallium nitride (GaN) layer; a GaN-based alloy layer having a top side and disposed on the GaN layer, wherein source, drain, and gate contact structures are supported by the GaN layer; and a first doped region positioned in a drain access region and extending from the top side into the GaN layer.

Abstract: Fabrication methods and gallium nitride transistors, in which an electronic device includes a substrate, a buffer structure, a hetero-epitaxy structure over the buffer structure, and a transistor over or in the hetero-epitaxy structure. In one example, the buffer structure has an extrinsically carbon doped gallium nitride layer over a dual superlattice stack or over a multilayer composition graded aluminum gallium nitride stack, and a silicon nitride cap layer over the hetero-epitaxy structure.

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: 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 method of fabricating a semiconductor device includes providing a GaN substrate with an epitaxial layer formed thereover, the epitaxial layer forming a heterojunction with the GaN substrate, the heterojunction supporting a 2-dimensional electron gas (2DEG) channel in the GaN substrate. A composite surface passivation layer is formed over a top surface of the epitaxial layer, wherein the composite surface passivation layer comprises a first passivation layer portion formed proximate to a first region of the GaN device and a second passivation layer portion formed proximate to a second region of the GaN device. The first and second passivation layer portions are disposed laterally adjacent to each other over the epitaxial layer, wherein the first passivation layer portion is formed in a first process and the second passivation layer portion is formed in a second process.

Abstract: In a described example, an integrated circuit (IC) is disclosed that includes a transistor. The transistor includes a substrate, and a buffer structure overlying the substrate. The buffer structure has a first buffer layer, a second buffer layer overlying the first buffer layer, and a third buffer layer overlying the second buffer layer. The first buffer layer has a first carbon concentration, the second buffer layer has a second carbon concentration lower than the first carbon concentration, and the third buffer layer has a third carbon concentration higher than the second carbon concentration. An active structure overlies the buffer structure.

Abstract: An integrated circuit (IC) includes a lower group III-N layer having a first composition over a substrate, and an upper group III-N layer having a different second composition over the lower group III-N layer. A gate electrode of a High Electron Mobility Transistor (HEMT) is located over the upper group III-N layer. First and second resistor contacts make a conductive connection to the lower group III-N layer. An unbiased group III-N cover layer is located on the upper group III-N layer in a resistor area including a high Rs 2-DEG resistor, where the unbiased group III-N cover layer is positioned between the first and second contacts.

Abstract: A semiconductor structure includes a first transistor including a gate structure, a drain, and a source. The gate structure of the first transistor includes a nitride-based semiconductor layer. The semiconductor structure further includes a second transistor including a gate structure, a drain, and a source. The gate structure of the second transistor also includes a nitride-based semiconductor layer. The nitride-based semiconductor layer of the first transistor's gate structure is continuous with the nitride-based semiconductor layer of the second transistor's gate structure.

Abstract: In a described example, an integrated circuit (IC) is disclosed that includes a transistor. The transistor includes a substrate, and a buffer structure overlying the substrate. The buffer structure has a first buffer layer, a second buffer layer overlying the first buffer layer, and a third buffer layer overlying the second buffer layer. The first buffer layer has a first carbon concentration, the second buffer layer has a second carbon concentration lower than the first carbon concentration, and the third buffer layer has a third carbon concentration higher than the second carbon concentration. An active structure overlies the buffer structure.

Abstract: A microelectronic device includes a GaN FET on a substrate such as silicon and a buffer layer of III-N semiconductor material. The GaN FET includes both source contacts and drain contacts to a channel layer of III-N semiconductor material. Source contacts to the source region are placed farther from the gate electrode fingertip than drain contacts to the drain region.

Abstract: A semiconductor structure includes a first transistor including a gate structure, a drain, and a source. The gate structure of the first transistor includes a nitride-based semiconductor layer. The semiconductor structure further includes a second transistor including a gate structure, a drain, and a source. The gate structure of the second transistor also includes a nitride-based semiconductor layer. The nitride-based semiconductor layer of the first transistor's gate structure is continuous with the nitride-based semiconductor layer of the second transistor's gate structure.