High electron density and mobility in single and double planar doped InGaAs/InAlAs heterojunctions on InP

Abstract

We present results of a growth study concerning the electrical properties of lattice matched InAlGa/InGaAs single planar doped (SPD) and double planar doped (DPD) heterostructures grown on InP by molecular beam epitaxy (MBE). It is shown that room temperature electron mobilities (μ H) as high as 11000 cm 2/V·s at high sheet densities of 2.8x10 12 cm −2 can be obtained by optimizing the growth temperatures of each material in the SPD structure. High performance two-dimensional electron gas field effect transistors (TEGFET's) are demonstrated, with transconductances as high as 420 mS/mm at 1 μm gatelength and ƒ T's of 46 GHz at 0.7 μm gatelength. The DPD heterostructures further boost the n s values up to 6.2x10 12 cm -2 at μ H (300 K) = 6000 cm 2/ Vctdot; s.