Effects of Source Access Resistance on Gate lag in AlGaN/GaN HEMTs and Current Slump Behavior

In summary, two-dimensional transient simulations of AIGaN/GaN HEMTs have been made in which a deep donor and a deep acceptor are considered in the buffer layer. The lag phenomena and current slump could be reproduced. Particularly, it has been shown that the gate lag is correlated with relatively high source access resistance of AIGaN/GaN HEMTs, and that the drain lag could be a major cause of current slump. It is concluded that an acceptor density in the buffer layer should be made low to minimize current slump, although current cutoff behavior may be degraded when the gate length becomes short.