Dummy Wafers Simulating Silicon from Glass or Fused Silica

With the advent of 300 mm Silicon wafer technology, a need has arisen for Silicon wafer substitutes. Valley Design took the initiative many years ago by introducing Glass and Ceramic wafers made to SEMI specifications. Newly available, Valley can now provide dummy wafers up to 450 mm diameter, with surfaces either lapped opaque or polished transparent.

The usual glass for this purpose is Soda Lime or Borosilicate. When temperature is involved, Borosilicate withstands higher temperatures. Valley Design offers a full line of different glasses and even Quartz or Ceramic material for this application.

Standard sizes are 2″, 3″, 100mm, 125mm, 150mm, 200mm, 300mm and 450mm diameters. Thickness can range from 0.005 inches to several millimeters. Edges are ground and beveled, and an indexing notch or flat is optional.