Crystallization Thickness of Amorphous Sb Film on GeO_<i>x</i>Film Substrate in a Vacuum of 10^-5Torr

Abstract

Antimony films with thicknesses smaller than a critical value, deposited at room temperature, are composed of amorphous islands. Amorphous Sb film on GeOx film substrate starts to crystallize spontaneously when the fractional area occupied by Sb exceeds 70-80% in the vicinity of the critical thickness, here called the crystallization thickness dc. The value of dc is increased by exposing GeOx to air before evaporating the Sb; it is 60-80 Å for as-deposited GeOx but 100-120 Å for that exposed to air. This is because the compound islands on as-deposited GeOx cannot contract as easily as those on GeOx exposed to air after the coalescence of islands with neighbouring ones to form a continuous film.