摘要 |
A spin chuck for holding semiconductor wafers includes one or more damping mechanisms to limit the force with which chuck pins impact the wafer edge following wafer shift. The damping mechanism may be a linear or rotary dashpot. The dashpot or dashpots are mounted on a surface of the chuck body and include a control arm that contacts a common gear ring that in turn drives the chuck pins during radially inward and outward movement. |