Evolution of structural defects associated with electrical degradation in AlGaN/GaN high electron mobility transistors

摘要: We have investigated the surface morphology of electrically stressed AlGaN/GaN high electron mobility transistors using atomic force microscopy and scanning after removing gate metallization by chemical etching. Changes in were correlated with degradation electrical characteristics. Linear grooves formed along edges GaN cap layer for all devices. Beyond a critical voltage that corresponds to sharp increase leakage current, pits on at edges. The density size stress time correlate drain current collapse. believe mechanical AlGaN due high-voltage stressing is relieved formation these defects which act as paths result trapping transport properties channel underneath.