  We investigated temperature dependence of contact resistance of an
Au-Ti-Pd2Si ohmic contact to heavily doped n+-Si. The contact resistance
increases with temperature owing to conduction through the metal shunts. In
this case, the limiting process is diffusion input of electrons to the metal
shunts. The proposed mechanism of contact resistance formation seems to realize
also in the case of wide-gap semiconductors with high concentration of surface
states and dislocation density in the contact.
