| 摘要 |
Alignment apparatus particularly for a semiconductor wafer (140) includes a horizontal support plate (134), a horizontal rotatable theta plate (106) below the support plate and a horizontal x-y motion plate below the rotatable plate. Three piezoelectric linear drive motors (128-130) are mounted depending from the rotatable plate and having linear shafts (128a, etc.) extending thereabove to support the support plate, drive the support in the z-axis and then differentially operated to tilt the support plate. A pair of linear piezoelectric motors (110,115) drive the motion plate in x- and y-directions. A theta drive linear piezoelectric motor (137) functions to rotate the theta plate (106). Flexure connections (113, 117, 119, 121, 138, 144) are provided between the various motors and plates. Mask registration means (124, 125) extends upwardly past the edges of the plates to initially gap the wafer-to-mask distance. The mask (150) is held in a separate aligner (153) above the wafer (14) mounted on the support plate. The assembly of six piezoelectric motors and flexural linkages provides for movement of a wafer in six degrees of freedom. |
