PRE-ALIGNMENT DEVICE AND METHOD FOR WAFER

摘要

A pre-alignment device for a wafer comprises: a working platform, used for bearing a wafer, wherein the wafer is provided with a first alignment mark (W1) and a second alignment mark (W2) distributed approximately symmetrical to the circle center of the wafer; a peripheral vision collection system (1), used for marking a relative position of the working platform according to an edge or notch on the wager, so as to implement a first position compensation of the wafer; and a mark detection system (4), used for separately acquiring images of the first alignment mark (W1) and the second alignment mark (W2), and determining a relative position relationship between the circle center of the wafer and the working platform according to the positions of the first alignment mark (W1) and the second alignment mark (W2) in a coordinate system of the mark detection system, so as to implement a second position compensation of the wafer, wherein the horizontal axis (X) of the coordinate system of the mark detection system (4) is defined as a connection line between the center of the working platform and the center of the mark detection system (4), and the vertical axis (Y) is defined as a straight line that is perpendicular to the horizontal axis (X) and that passes through the center of the working platform.