Patent ID: 6327034
Filing Date: 2001-12-04
Classification: G03F

Abstract:
A system for aligning a mask and a product with high precision, comprising:a) a product securing surface, said product securing surface comprising a porous plate, a means for applying vacuum through said porous plate, and at least two registration pins that fit through registration holes in the product;b) a mask positioning surface for positioning a mask surrounded by a rectangular mask frame having at least two holes therethrough above the product, said mask positioning surface comprising a holding plate to support said mask frame and at least two alignment pins that fit through said holes in said mask frame;c) at least one movable first plunger that presses against a first edge of said mask frame;d) two movable second plungers that press against a second edge of said mask frame, said second edge being perpendicular to said first edge;e) at least one first computer-controlled movable push plate that moves said mask frame in a first direction by pushing said mask frame against at least one movable first plunger;f) two second movable computer-controlled movable push plates that either (a) move said mask frame in a second direction by pushing said mask frame against said two movable second plungers; or (b) rotate said mask frame by moving one of the said second movable push plates toward one of the said movable second plungers, while simultaneously moving the other of the said second movable push plates away from the other of the said movable second plungers; andg) a determining and signaling means for determining the relative position of the mask and product prior to alignment; determining that, to achieve ideal alignment, the mask must be moved in said first direction by a first distance, moved in said second direction by a second distance, and rotated by a defined amount; signaling said at least one first computer-controlled movable push plate to move said mask frame in said first direction by said first distance; signaling said two second computer-controlled movable push plates to move said mask frame in said second direction by said second distance; and signaling said two second computer-controlled movable push plates to rotate said mask frame by said defined amount.