Patent ID: 9263530
Filing Date: 2016-02-16
CPC Classification: H01L

Claim Text:
1. A field effect transistor, comprising: a substrate; a C-doped semiconductor layer disposed on the substrate; a channel layer disposed on the C-doped semiconductor layer; an electron supply layer disposed on the channel layer, wherein a two-dimensional electron gas generates in an interface between the channel layer and the electron supply layer; and a diffusion barrier layer comprising an Al content and disposed between the C-doped semiconductor layer and the channel layer, wherein the diffusion barrier layer contacts the channel layer and the C-doped semiconductor layer directly, and a thickness of the diffusion barrier layer is between 5 nm and 30 nm, wherein the Al content in the diffusion barrier layer decreases or increases from the middle of the diffusion barrier layer toward the channel layer and the C-doped semiconductor layer, respectively.