| 摘要 |
A workpiece cooling system and method are disclosed. Transferring heat away from a workpiece, such as a semiconductor wafer during ion implantation, is essential. Typically this heat is transferred to the workpiece support, or platen. In one embodiment, the desired operating temperature is determined. Based on this, a gas having a vapor pressure within a desired range, such as 10-50 torr, is selected. This range is required to be sufficiently low so as to be less than the clamping force. This condensible gas is used to fill the volume between the workpiece and the workpiece support. Heat transfer occurs based on adsorption and desorption, thereby offering improved transfer properties than traditionally employed gases, such as helium, hydrogen, nitrogen, argon and air. |
