METHOD OF ETCHING PLATINUM FILM OF SEMICONDUCTOR DEVICE

摘要

PROBLEM TO BE SOLVED: To provide a method of etching a platinum film for use as a lower electrode of a semiconductor device capacitor. SOLUTION: Utilizing the characteristics that a Ti adhesive layer 106 on a Pt film 108 is etched with an O-rich etching gas to form a TiOx layer serving as an additional etching mask and such TiOx layer 15 formed enough to block the entire mask 110 from corroding, the Pt film 108 is overetched to improve the etching gradient of this film. To form the TiOx film enough to block the mask 110 from corroding, the temp. of a semiconductor substrate 100 is set in a range of 120-300 deg.C.