On the temperature and carrier density dependence of electron saturation velocity in an AlGaN/GaN HEMT

The temperature and carrier density dependence of electron intrinsic saturation velocity (v/sub si/) in a 0.3-/spl mu/m gate length AlGaN/GaN HEMT was extracted from multibias S-parameter measurements. It was found that v/sub si/ fell rapidly with increasing sheet carrier concentration (n/sub s/), but was only a very weak function of ambient temperature (T/sub amb/). This behavior is consistent with the hot-phonon model of carrier transport.