Patent ID: 6170432
Filing Date: 2001-01-09
Classification: C23C,H01J

Abstract:
A showerhead electrode assembly for a plasma reactor system for processing semiconductor wafers, comprises:a disk shaped gas plate having an upper portion of smaller diameter than a lower portion, the face of the upper portion providing a first side of said gas plate, the face of the lower portion providing a second side of gas plate, a peripheral acutely angled first groove being formed between said first side and said lower portion, said first groove terminating at a band-like ledge of said lower portion;a locking ring including identical semicircular first and second sections each having a peripheral acutely angled second groove in a lower portion of respective inside sidewalls thereof, said second grooves being conformed to interlock with and receive said ledge with respective ends abutting, and each further including an upper portion protruding above said ledge and said first side of said gas plate;a unitary circular support collar having opposing top and bottom portions, said bottom portion being formed with a circular channel extending into a bottom face thereof, forming a circumferential outer bottom surface on one side of said channel, and a circumferential inner bottom surface on the other side of said channel, the outer bottom surface vertically extending beyond the inner bottom surface, said channel being configured to receive the portions of said first and second sections of said locking ring protruding above said ledge and first side of said gas plate;said support collar having its channel forced onto protruding of said first and second locking ring sections mounted on said ledge, for in turn forcing the second groove of each of said locking ring sections, respectively, to engage and interlock with the first groove of said gas plate, the outer bottom surface of said support collar abutting against said ledge, and the inner bottom surface abutting against the first side of said gas plate; andmeans for rigidly securing together said first and second sections of said locking ring, and a portion of the channel of said support collar.