Method of ion implantation through an electrically insulative material

Abstract

A method of ion implantation into a semiconductor substrate which comprises forming a layer of an electrically insulative material, such as silicon dioxide, on the substrate over the region to be ion implanted. Then, a beam of ions having sufficient energy to pass through the layer of insulative material and to penetrate into the substrate is directed at a particular portion of the insulative layer. Before proceeding further, at least the upper half of the insulative layer, and preferably all of the upper portion of the insulative layer, in excess of a remaining thickness of 100A, is removed by etching. Then, the substrate is heated whereby the ions are driven further into the substrate to form the selected ion implanted region.

Dependencies are inferred from the claim text.