On the trap assisted stress induced safe operating area limits of AlGaN/GaN HEMTs

Abstract

This experimental study reports a systematic investigation of Safe Operating Area limits in AlGaN/GaN HEMT using sub-μs pulse characterization with on the fly Raman and CV characterization to probe defect and stress evolution across the device. Influence of a recess depth on SOA boundary is analyzed. Post failure analysis corroborates well with the failure physics unveiled in this work.

Recent progress of physical failure analysis of GaN HEMTs

“…On the other hand, in situ SiN x has advantages in improving defect levels and dielectric qualities when compared with ex situ SiN x . A near-ideal dielectric breakdown strength of ~13.2 MV/cm, a high interface quality with a state density of ~3.0 × 10 12 eV -1 cm -2 and a maximum forward bias as high as 19.5 V (~3.66 MV/cm) for a ten-year lifetime at the failure level of 0.01% are obtained by Cheng et al [53] . The as-proposed in situ SiN x grown method offers an appropriate replacement for the passivation optimization, hence providing extra process facilitations and design adaptabilities.…”