High - field transport properties of ! lnAs , P , - , / lnP ( 0 . 3 gxg I . Q ) modulation doped heterostructures at 300 and 77

We have measured the high-field transport characteristics of pseudomorphic InAs,Pi JInP (0.3<x<l.O) modulation doped heterostructures at 300 and 77 K. The field dependent steady state average velocities increase steadily with increase in x. The maximum velocities that have been measured in InAs/InP are 1.7~ lo7 cm/s (2.5 kV/cm) and 3.2~ 10’ cm/s (2.2 kV/cm) at 300 and 77 K, respectively. These are the highest velocities measured in any modulation doped heterostructure. The field dependent channel carrier concentration and mobility data indicate that there is very little real space transfer of carriers at high fields and this is confirmed by results from steady state Monte Carlo calculations.