Suppression of the surface-inversion layer of p-type InAs

The resistivity of spatially selectable regions on p-type InAs is increased by epitaxial growth of a larger band-gap material, i.e., InAlAs, on top of InAs. Due to this InAlAs layer, the formation of a two-dimensional electro n gas in the InAs layer is suppressed. This is demonstrated experimentally and supported by calculations of the conductance and valence band profile. At low temperature (4.2 K), the resistance of p-InAs coated with InAlAs and InGaAs is increased by a factor of 180 compared with bare p-InAs. (C) 1999 American Institute of Physics. [S0021-8979(99)06612-8].