Study of passivation defects by electroluminescence in AlGaN/GaN HEMTS on SiC

This paper presents a new method of passivation control by electroluminescence (EL) in 0.15 lm AlGaN/GaN HEMT. The electroluminescence signature in one finger HEMTs (W = 1 · 100 lm), and eight fingers ones (W = 8 · 125 lm), is modified by defects located at the passivation/semiconductor interface and is characterized by a light emission along the drain contact. This abnormal emission reveals some modification of the electric field distribution in the gate-drain space probably induced by traps located at the passivation/semiconductor interface. These traps contribute to the creation of a virtual gate in the gate-drain space. 2007 Elsevier Ltd. All rights reserved.