| 摘要 |
The present disclosure relates to a wafer chuck configured to provide a uniform photoresist layer on a workpiece. In some embodiments, the wafer chuck comprises a plurality of vacuum holes. The plurality of vacuum holes (i.e., more than one) are in fluid communication with a cavity that continuously extends along the top surface between the vacuum holes. A vacuum source, connected to each vacuum hole, is configured to remove gas molecules from the cavity located below the workpiece leaving behind a low pressure vacuum. The use of a plurality of vacuum holes increase the uniformity of the vacuum, thereby preventing the formation of high vacuum areas in close proximity to any specific vacuum hole. The reduction of high vacuum areas reduces wafer bending associated with the high vacuum areas. |
