The impact of dislocations on AlGaN/GaN Schottky diodes and on gate failure of high electron mobility transistors.

ABSTRACT: GaN epitaxially grown on Si is a material for power electronics that intrinsically shows a high density of dislocations. We show by Conductive Atomic Force Microscopy (C-AFM) and Defect Selective Etching that even for materials with similar total dislocation densities substantially different subsets of dislocations with screw component act as current leakage paths within the AlGaN barrier under forward bias. Potential reasons are discussed and it will be directly shown by an innovative experiment that current voltage forward characteristics of AlGaN/GaN Schottky diodes shift to lower absolute voltages when such dislocations are present within the device. A local lowering of the Schottky barrier height around conductive dislocations is identified and impurity segregation is assumed as respo

SUBMITTER: Besendorfer S 

PROVIDER: S-EPMC7560755 | biostudies-literature | 2020 Oct

REPOSITORIES: biostudies-literature