Autoaligned etching process for realizing word lines in memory devices integrated semiconductor substrates

Abstract

Self-aligned etching process for providing a plurality of mutually parallel word lines in a first conducting layer deposited over a plagiarized architecture obtained starting from a semiconductor substrate on which is provided a plurality of active elements extending along separate parallel lines e.g., memory cell bit lines and comprising gate regions made up of a first conducting layer, an intermediate dielectric layer and a second conducting layer with said regions being insulated from each other by insulation regions to form said architecture with said word lines being defined photolithographically by protective strips implemented by means of: a vertical profile etching for complete removal from the unprotected areas of the first conducting layer of the second conducting layer and of the intermediate dielectric layer respectively, and a following isotropic etching of the first conducting layer.