METODO PER PRODURRE IM UN SEMICONDUTTORE UN ELEMENTO IN TUNGSTENO PER UN'INTERCONNESSIONE

• Main Author: KIM EUI-SONG
• Format: Patent
• Language: Italian
• Published: 05.01.1992
• Edition: 5
• Subjects: BASIC ELECTRIC ELEMENTS; ELECTRIC SOLID STATE DEVICES NOT OTHERWISE PROVIDED FOR; ELECTRICITY; SEMICONDUCTOR DEVICES

Method for producing a tungsten element for an interconnection in a semiconductor, comprising the steps of: forming a film of polysilicon 18 on top of a first insulating film 12 of a semiconductor substrate 11 and doping with impurities; forming a film of highly doped oxide 19 on top of the film of polysilicon and then creating a pit for the metallic interconnection; selectively growing tungsten 15 on an exposed part of the film of polysilicon in the said pit; removing the film of highly doped oxide by wet etching and etching a residue 20 of the tungsten formed on the oxide film; dry etching the polysilicon, using the tungsten on the polysilicon as an etching mask which leaves the polysilicon only under the tungsten. (Fig. 3C)