Abstract: A semiconductor device includes a type IV semiconductor base substrate, a first type III-V semiconductor layer formed on a first surface of the base substrate, and a second type III-V semiconductor layer with a different bandgap as the first type III-V being formed on the first type III-V semiconductor layer. The semiconductor device further includes first and second electrically conductive device terminals each being formed on the second type III-V semiconductor layer and each being in ohmic contact with the two-dimensional charge carrier gas. The base substrate includes a dielectric layer formed directly on a lower region of type IV semiconductor material, and a highly-doped layer of type IV semiconductor material formed directly on the dielectric layer.

Abstract: A semiconductor device includes a type IV semiconductor base substrate, a first type III-V semiconductor layer formed on a first surface of the base substrate, and a second type III-V semiconductor layer with a different bandgap as the first type III-V being formed on the first type III-V semiconductor layer. The semiconductor device further includes first and second electrically conductive device terminals each being formed on the second type III-V semiconductor layer and each being in ohmic contact with the two-dimensional charge carrier gas. The base substrate includes a first highly doped island that is disposed directly beneath the second device terminal and extends to the first surface of the base substrate. The first highly-doped island is laterally disposed between portions of semiconductor material having a lower net doping concentration than the first highly-doped island.

Abstract: A semiconductor device includes a type IV semiconductor base substrate, a first type III-V semiconductor layer formed on a first surface of the base substrate, and a second type III-V semiconductor layer with a different bandgap as the first type III-V being formed on the first type III-V semiconductor layer. The semiconductor device further includes first and second electrically conductive device terminals each being formed on the second type III-V semiconductor layer and each being in ohmic contact with the two-dimensional charge carrier gas. The base substrate includes a first highly doped island that is disposed directly beneath the second device terminal and extends to the first surface of the base substrate. The first highly-doped island is laterally disposed between portions of semiconductor material having a lower net doping concentration than the first highly-doped island.