常关断型hemt晶体管

This utility model relates to normally-off type HEMT transistor.A kind of normally-off type HEMT transistor includes: heterojunction semiconductor (4,6,200), and it at least includes a ground floor (4) and a second layer (6), and the second layer is arranged on the top of ground floor；Groove (15), it extends through a part for the second layer and ground floor；The gate regions (10) of conductive material, it extends in the trench；And dielectric regime (18), it extends in the trench, coats gate regions and contacts heterojunction semiconductor.A part for groove is by forming at least one first step (Pb1、Pl1、Pb2) transversary (LS) laterally delimit.Heterojunction semiconductor forms the first edge (E of first step1) and the second edge (E2), the first edge is formed by ground floor.