Anomaly and threshold voltage shifts in GaN and GaAs HEMTs over temperature

Abstract

The anomalies and the threshold voltage shifts in GaN and GaAs based high electron mobility transistors over temperature were reported and analyzed using on wafer measurements. Discrepancies are noticed; most conspicuously that the thermal trends of the threshold voltage of the two device technologies are utterly contrasting. This anomaly extends for the other parameters of the devices such as sheet carrier densities of the two-dimension electron gas. In addition barrier inhomogeneities and the band offset of the semiconductor heterojunction with temperature provides some valuable insights between the two competitive device technologies.