Title :
Integration of an in situ RIE preclean with a CVD tungsten silicide deposition process
Author :
Nowicki, Ronald S. ; Geraghty, Patrice ; Fuhs, Clark
Author_Institution :
Genus Inc., Mount View, CA, USA
Abstract :
The in situ process capability of native oxide removal affords an advantage over the conventional method of aqueous hydrofluoric acid cleaning prior to a film deposition step. A technique is described in which an in situ predeposition clean with C2F6 gas, using reactive ion etching (RIE) prior to tungsten silicide deposition, is employed. This technique allows post-silicide-deposition high-temperature heat treatment and wet oxidation without loss of film adhesion or other obvious degradative effects. Also reported is the use of secondary ion mass spectrometry (SIMS) to show that this procedure has been effective in the removal of the oxide layer prior to silicide deposition. This study includes definition of the RIE etch parameters which provide acceptable etch selectivity of the oxide to silicon, and avoidance of excessive fluoropolymer formation on the silicon surface
Keywords :
VLSI; chemical vapour deposition; integrated circuit technology; metallisation; semiconductor technology; sputter etching; tungsten compounds; CVD WSi2 deposition process; RIE; RIE etch parameters; SIMS; Si; SiO2 etching; WSi2-Si; etch selectivity; film adhesion; fluoropolymer formation avoidance; hexafluoroethane gas; in situ RIE preclean; in situ predeposition clean; in situ process capability; native oxide removal; post-silicide-deposition high-temperature heat treatment; reactive ion etching; secondary ion mass spectrometry; silicide deposition; wet oxidation; Adhesives; Cleaning; Degradation; Etching; Heat treatment; Mass spectroscopy; Oxidation; Silicides; Silicon; Tungsten;
Conference_Titel :
VLSI Multilevel Interconnection Conference, 1990. Proceedings., Seventh International IEEE
Conference_Location :
Santa Clara, CA
DOI :
10.1109/VMIC.1990.127931