Mounting device and wafer positioning system for wafer in plasma etching plant has device for adjusting position of wafer in form of lift pin

摘要

The wafer (1) is held in position by an electrostatic chuck (4) against an electrode (3). A focus ring (2) surrounds the wafer. The ring leaves a free space below the section of the wafer which projects outside the chuck and between ring and wafer. To fill this space a positioning device (31) in the form of Elift pinse is provided so that the wafer can be positioned against the focus ring, the position being monitored by a camera. Provision can be made so that the device can also have a small horizontal movement, e.g. approx. 1mm.