摘要
研究了GaNHFET中沟道热电子隧穿到表面态及表面态电子跃迁到表面导带两种跃迁过程及其激活能.从沟道热电子隧穿过程出发,提出了新的电流崩塌微观模型.用该微观模型解释了光离化谱、DLTS、瞬态电流及电流崩塌等各类实验现象.研究了各种异质结构的不同电流崩塌特性,在此基础上讨论了无电流崩塌器件的优化设计.
Two electron transition processes between channel and surface states in GaN HFET:hot electron tunneling and surface to band edge transition are investigated. Based on the tunneling between channel hot electrons and surface states, a new microscope mechanism of current collapse is proposed. Various experimental behaviors of photoionization spectroscopy, DLTS, transient current,and current collapse are explained by this microscopic mechanism. The different current collapse behaviors are investigated for various heterostructures,from which the optimized design of GaN HFET without current collapse is discussed.