Patent ID: 8183572
Filing Date: 2012-05-22
Classification: H01L

Abstract:
1. A compound semiconductor device comprising: a conductive semiconductor substrate; a drain electrode formed on a bottom surface of said conductive semiconductor substrate; a current blocking layer formed on a top surface of said conductive semiconductor substrate, made of high resistance compound semiconductor or insulator, and having openings; an active layer of compound semiconductor burying said openings and extending on an upper surface of said current blocking layer; a gate electrode of comb-shape having gate teeth formed above said openings and above said active layer, each of the openings being covered with one of the gate teeth, and the gate electrode of comb-shape having a base connecting the gate teeth; and a source electrode of comb-shape laterally spaced from said gate electrode, having source teeth on both sides of each of the gate teeth and formed above said active layer, the source electrode of comb shape having a base connecting the source teeth, wherein said conductive semiconductor substrate is made of SiC or GaN, said current blocking layer is made of AlN, and said active layer includes a GaN region filling said openings and extending on the current blocking layer, and wherein said active layer includes an underlying n-type AlGaN layer between said GaN region and said AlN current blocking layer.