Degradation Study of Single and Double-Heterojunction InAlN/GaN HEMTs by Two-Dimensional Simulation

We study the concept of double-heterostructure quantum well (DHQW) InAlN/GaN/AlGaN high electron mobility transistor (HEMT) for higher device robustness and less degradation. Physics-based device simulation proves that the back barrier blocks the carrier injection into the device buffer. However, the energy of the injected electrons in the buffer is higher for any quantum well design in InAlN /GaN than in AlGaN/GaN HEMTs. This energy may be sufficient for releasing hydrogen from GaN point defects.