Demonstration and dynamic analysis of trapping of hot electrons at gate edge model for current collapse and gate lag in GaN-based high-electron-mobility transistor including self-heating effect

Using a two-dimensional simulator, the authors report on demonstration of trapping of hot electrons at gate edge model in GaN-based high-electron-mobility transistors. Dynamic picture of hot electrons under gate pulse voltage is discussed in detail. Trapped charges may accumulate under punch-off gate voltage at gate edge drain side, where the electric field significantly changes and gate-voltage-dependent strain is induced. Significant band barrier is formed at the gate edges causing a notable current collapse. Self-heating effect is one of the reasons for current collapse and gate lag.