Vertical Leakage/Breakdown Mechanisms in AlGaN/GaN-on-Si Devices

摘要

Vertical leakage/breakdown mechanisms in AlGaN/GaN high-electron-mobility transistors grown on low-resistivity p-type (111) Si substrate are studied by temperature-dependent current–voltage ( $I$–$V$) measurements. It is found that the top-to-substrate vertical breakdown voltage $(BV)$ is dominated by the space-charge-limited current conduction involving both acceptor and donor traps in the GaN buffer/transition layer. From the temperature-dependent transient backgating measurements, the acceptor level at $E_{V} + hbox{543} hbox{meV}$ and the donor level at $E_{C}$-616 meV were identified.