METHOD FOR FABRICATING SEMICONDUCTOR DEVICES USING COMPOSITE MASK AND ION IMPLANTATION

摘要

A method for fabricating semiconductor devices from a semiconductor body having a planar surface by forming on the surface a layer of protective material which is to be utilized as a mask. A plurality of windows are formed simultaneously in the layer of protective material to expose said surface to permit the subsequent formation of isolation regions, base regions and collector contact regions in the semiconductor body. Ion implantation is carried out at low temperatures through certain of the openings while covering the other openings to form the respective regions thereby eliminating the necessity for mask to mask tolerance requirements and tolerances required for thermal diffusions.