SEMITIP V6, UniInt1, Example 1: n-type GaAs(110)

Click here for input/output files for Example 1

This example illustrates the conductance vs. voltage for n-type GaAs doped at 1018 cm-3, assuming a contact potential of 0 eV. A Gaussian-shaped band of intrinsic surface states (i.e. associated with the Ga dangling bonds on the surface) are placed at 1.75 eV above the valence band maximum, with width (FWHM) of the band of 0.25 eV. These surface states restrict the formation of an accumulation layer, so that essentially all of the current throughout the gap originates from extended states in the conduction band that are occupied due to the n-type doping. Output for the conductance goes to FORT.93, FORT.94, and FORT.15 for the valence band (VB), conduction band (CB), and their sum, respectively. When we plot the total conductance (sum of conductance from extended states plus localized states) in each case, we find:

The result is similar to what occurs in 2D, as in Example 1 of UniInt2, although the details of the present 1D case are different.