PLASMA & MATERIALS TECHNOLOGIES, INC. EXHIBIT 23.1--CONSENT OF INDEPENDENT AUDITORS We consent to the incorporation by reference, in the Registration Statement (Form S-8 No. 33-94450) pertaining to the 1991 Stock Option Plan of Plasma & Materials Technologies, Inc., of our report dated January 30, 1996, with respect to the consolidated financial statements included in the Annual Report on Form 10-K of Plasma & Materials Technologies, Inc. for the year ended December 31, 1995. ERNST & YOUNG LLP Woodland Hills, California March 27, 1996