Transport properties of InAlAs/InGaAs metamorphic high electron mobility transistors on GaAs substrate

Variable magnetic field Hall measurement has been used to investigate the transport properties in InAlAs/InGaAs metamorphic high electron mobility transistors (MMHEMT) on GaAs substrate in the temperature range from 1.5 to 90K. The experimental data have been analyzed by using a hybrid approach consisting of the mobility spectrum (MS) technique followed by a multi-carrier fitting (MCF) procedure. Both the Shubnikov-de Haas measurements and the hybrid MS+MCF approach show two-dimensional electronic behavior. The two-dimensional electrons, with mobility ∼3×10⁴cm²/Vs and a sheet density ∼2.3×10¹²cm^-2, are obtained and come from the quantum well. The temperature dependent evolution of the electron mobility indicates that alloy scattering dominates at higher temperature.