Abstract: A method for fabricating contacts in a semiconductor substrate includes forming a thin buffer oxide layer (26) over a substrate (10) with active devices defined therein. Access openings (28), (30) and (32) are then formed in the thin oxide layer (26) and then aluminum columnar contacts (38), (40) and (42) formed therein with a predetermined height. A thick oxide layer of phosphorous silicate glass (50) is then formed over the built-up structure. A planarizing resist layer (52) is formed over top of the structure with a substantially thinner area defined proximate the upper surfaces of the columnar contacts (38, 40, 42). The thin areas (54, 56, 58) are removed by selectively etching away the upper surface of the resist layer (52) by an excited plasma process. The structure is then subjected to a phosphorous selective etch to remove only those portions of the thick oxide layer (52') proximate the upper surfaces of the columnar contacts (38, 40, 42).

Abstract: The disclosure relates to the formation of reachup contacts for VLSI integrated circuit interconnects wherein studs are formed of a conducting material which reaches up through subsequently applied insulating films or the like to contact metal patterns. The reachup contacts are fabricated using LPCVD polycrystalline silicon as a refill in etched apertures in an insulating layer with a titanium or other appropriate material over the silicon layer with subsequent reaction of the silicon layer and the titanium layer to form temperature resistant studs of titanium silicide.