Process for preparing thin semiconductor films

摘要

A semiconductor thin film prodn. process involves (a) ion implantation (12) across a semiconductor wafer face (14), which is parallel to a crystallographic plane of the semiconductor, in order to form a cleavage layer (16) of gaseous micro-bubbles which delimits a surface layer (18) in the wafer (10); and (b) wafer heat treatment to cause separation of the surface layer (18) from the rest of the wafer along the micro-bubble layer by the effects of crystalline rearrangement and pressure in the micro-bubbles. The novelty is that the implantation energy is such that the ion penetration depth is greater than a minimum depth required to obtain a thin film of the surface layer which is sufficiently rigid for release by the heat treatment. Pref. the wafer is of silicon or silicon carbide and the minimum depth is 5 microns or 1.15 microns respectively.