| 摘要 |
A workpiece chuck includes an upper assembly on which can be mounted a flat workpiece such as a semiconductor wafer. A lower assembly is mountable to a base that supports the chuck. A non-constraining attachment means such as vacuum, springs or resilient washers applied to the chuck holds the upper assembly to the lower assembly, the lower assembly to the base and can hold the wafer to the top surface of the upper assembly. A heater and a heat sink can be included in the bottom assembly to allow for temperature cycle testing of the wafer. By holding the chuck together by non-constraining means, the chuck layers can move continuously relative to each other under expansion forces caused by temperature effects. Mechanical stresses on the chuck and resulting deformation of the chuck and workpiece over temperature are substantially eliminated.
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