Power high election mobility structure.

摘要

A modulating-doped field effect transistor comprises a substantially undoped channel layer (10), a n-doped wide bandgap donor layer (12) and a relatively heavily doped cap layer (14). It further comprises a gate recess (17) through a top insulating layer (16), having a cross-section in the cap layer (14) increasing down to the interface with the donor layer (12) and thereafter having a cross-section in said donor layer (12) decreasing down to the bottom of the recess (12) in said donor layer. A Schottky gate electrode (24) which does not occupy the portions of the recess (17) in the undercut part is formed in said recess (17) using the insulating layer (16) as a shadow mask.