Enhancement-Mode High Electron Mobility Transistors for Logic Applications

Abstract

Enhancement-mode high electron mobility transistors (E-HEMTs) with selectively doped GaAs/n-Al x Ga 1- x As heterojunction structures grown by molecular beam epitaxy are described. E-HEMTs with 2- µm long gates have exhibited the square-law drain characteristic. The device has a g m of 409 mSmm -1 of gate width at 77 K and 193 mSmm -1 at 300 K. This value of g m at 77 K is the highest in all field effect devices reported thus far.