Lower limits to specific contact resistivity

We calculate minimum feasible contact resistivities to n-type and p-type InAs and In_0.53Ga_0.47As. Resistivities were calculated for a range of Schottky barrier heights as well as for the case where the transmission probability is unity (Landauer limit). Calculations are compared with recent experimental data. Experimental contact resistivities for n-In_0.53Ga_0.47As and n-InAs lie within 2.5:1 of calculated resistivities given generally accepted values of Schottky barrier potential. Computed resistivities in the presence of a barrier are only 3.5:1 to 4:1 above Landauer limits.