Browse Prior Art Database

Wafer Holding Pedestal

IP.com Disclosure Number: IPCOM000074522D
Original Publication Date: 1971-May-01
Included in the Prior Art Database: 2005-Feb-23
Document File: 2 page(s) / 39K

Publishing Venue

IBM

Related People

Fiore, P: AUTHOR [+2]

Abstract

During photo-fabrication of integrated circuits, the wafer is normally vacuum clamped to a pedestal. When a flat polished wafer 10 is placed on top of this pedestal, and vacuum is applied, there is uniform clamping pressure to hold the wafer 10 to the disc 11 and it also gives a flat working wafer surface.

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Wafer Holding Pedestal

During photo-fabrication of integrated circuits, the wafer is normally vacuum clamped to a pedestal. When a flat polished wafer 10 is placed on top of this pedestal, and vacuum is applied, there is uniform clamping pressure to hold the wafer 10 to the disc 11 and it also gives a flat working wafer surface.

The pedestal consists of two parts: a stainless steel controlled porosity disc 11 and a vacuum holder base 12. The stainless steel controlled porosity disc 11 is fabricated by sintering stainless steel powder of selected grade and granular size (40 u). The top surface of the disc 11 is lapped and polished to a flatness of
0.00005 in/in. The vacuum holder base 12 has machined channels and concentric grooves to serve as a support for the disc 11, and to distribute vacuum uniformly to the disc 11. The disc 11 is cemented to the vacuum holder base 12 with epoxy.

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