A method for improving positioning performance, applied to a testing apparatus comprising a movement device and an imaging device, the testing apparatus configured to drive a wafer carrier of the movement device such that at least a portion of a standard sheet carried thereon is able to enter a field of view of the imaging device, the standard sheet comprising a plurality of reference marks arranged in an array;
- the method for improving positioning performance comprising:
- a positioning step of aligning a reference position on the standard sheet with a baseline position of the field of view;
- a rotation correction step of rendering, based on a geometric relation formed by at least two of the reference marks arranged in a same column or a same row, the standard sheet to a state without rotational deviation;
- and
- a coordinate compensation information establishment step for obtaining corresponding offset information of the wafer carrier in each of a plurality of target coordinates to establish a coordinate compensation information table, as a compensation basis when the wafer carrier is subsequently driven,
- wherein, when the wafer carrier is driven to sequentially align the baseline position with the target coordinates as driving destinations and has arrived at the driving destination of one of the target coordinates, a target position of the target coordinate in an image of the field of view is obtained based on distance information among the reference marks, and an offset amount between the target position and the baseline position in the field of view is used as the corresponding offset information.