Electronic device with enhancement mode gallium nitride transistor, and method of making same

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.