Brief description of the formation of films of polycrystalline silicon localized on the zones covered with silica of a silicon wafer and the application for the manufacture of a mos transistor is not plane self-aligned

摘要

A method for forming a self-aligned MOS power transistor. A layer of silicon nitride is deposited uniformly over a plate with limited oxide zones. The plate is then placed in an acid bath and subjected to a potential difference. Only the zones of the polycrystalline silicon layer which are over the silica zones remain.