Lower Limits To Metal-Semiconductor Contact Resistance: Theoretical Models And Experimental Data

We calculate the minimum feasible contact resistivity to n-type and p-type In0.53Ga0.47As, InAs, GaAs, GaSb, InP, and InSb. The calculations consider image force lowering and assume either parabolic or non-parabolic energy dispersion in the semiconductor; their results are compared with recent experimental data. Among significant results, the measured contact resistivity to n-In0.53Ga0.47As at a carrier concentration of 5 x 10(19) cm(-3) is only 2.3:1 higher than that calculated assuming a 0.2 eV barrier potential, and the measured contact resistivity is only 9.0:1 larger than the Landauer quantum conductivity limit at this carrier concentration. These results indicate that, with the surface preparation procedures presently employed, surface contamination does not markedly increase the interface resistance, and that the transmission coefficient for carriers crossing the interface exceeds 10%. (C) 2013 AIP Publishing LLC.