Semiconductor substrate and method for producing the same

摘要

A semiconductor substrate that comprises: a base plate member made from a dielectric material; a refractory metal film covering at least a part of the base plate member; a single crystal semiconductor film formed on the refractory metal film; and an impurities-diffusion layer formed in said single crystal semiconductor film in a side contacting with the refractory metla film. The diffusion layer has a density grade gradually decreasing toward a direction away from the refractory metal film so that this impurities-diffusion layer comes in ohmic contact with the refractory metal film.