M. Bouya, Thales Research and Technology, Palaiseau, France

Summary: This paper presents a new method of ohmic contact control by IR electroluminescence (IR EL) in eight fingers (W=8x125µm) AlGaN/GaN HEMT. And an abnormal electroluminescence (Vis-NIR) signature in two fingers (W=2x50µm) GaN HEMTs, linked to defects located at the GaN buffer /SiC substrate interface. In addition, there is a very strong correlation between the failure mode and the light emission signature. In this paper, we will focus on two key issues and describe several case studies of failure analysis solved by light emission microscopy.