A method of retaining a substrate to a wafer chuck. The method features
accelerating a portion of the substrate toward the wafer chuck,
generating a velocity of travel of the substrate toward the wafer chuck,
and reducing the velocity before the substrate reaches the wafer chuck.
In this manner, the force of impact of the portion with the wafer chuck
is greatly reduced, which is believed to reduce the probability that the
structural integrity of the substrate, and layers on the substrate and/or
the wafer chuck, are damaged.