Method and apparatus for removing heat from a workpiece during processing in a vacuum chamber

Abstract

Abstract A workpiece (16), for example a magnetic bubble memory wafer, is held in place, and heat is removed from it by an expandable heat pipe (22) during a process performed in a vacuum as, for example, a sputter etch process. The expandable heat pipe (22) includes two plates (24, 26) joined by a bellows (28) to form a sealed chamber containing a vaporizable liquid such as water. During loading of the wafers the heat pipe (22) is compressed by atmospheric pressure and thereby facilitates easy assembly of the wafer (16) and heat pipe (22) into a holding fixture (10) which in turn is bolted to a cooling plate (30) situated inside a vacuum chamber. When the chamber is evacuated, the heat pipe (22) expands to hold the wafer (16) in place and form a good thermal path from the wafer (16) to the cooling plate (30). In an alternate embodiment the heat pipe (22) does not completely fill the gap from the wafer (16) to the cooling plate (30) in a vacuum at room temperature, but rather expands to fill the gap when the heat pipe (22) is heated by the wafer (16). The expanding heat pipe (22) holds the wafer (16) at a constant, predetermined temperature above the temperature of the cold plate.

Inventors

• 👤 Robert W. Garrett

Bibliographic Details