Product Description
This 8 inch vacuum wafer chuck was removed from an OSI (Optical Specialties Inc) film thickness measurement system, Model FT650. The annular plate can be adjusted in height by two pairs of cam-driven ball bearings. The stroke appears to be about 1/4 inch.
In addition to Z-axis adjustment, there is a central vacuum piston that may be used to lift the wafer independently of the cam driven annular plate. It is pneumatically actuated by an air cylinder on the side of the assembly, but I am do not know what the stroke distance is. It would be used to lift the wafer for loading and unloading purposes. The diameter of the central piston is 1.5 inches.
Overall height of the assembly is about 3 inches, including a leveling plate on the base of the fixture. There are three very fine pitch (100 TPI) leveling screws.
We are unable to test the function of the stage. It appears to be in very fine condition.
Photo set 1516