| CPC G01N 21/9501 (2013.01) [H04N 23/56 (2023.01); H04N 23/60 (2023.01); H04N 23/74 (2023.01); G01N 2201/06113 (2013.01)] | 20 Claims |
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1. A wafer inspection system, comprising:
an optical device, comprising:
a light source, configured to generate an incident light and direct the incident light through an illumination optical toward a wafer, so as to generate a reflected light accordingly; and
an image sensor, configured to capture the reflected light through an imaging optical and generate an image of the wafer accordingly;
a movable stage, configured to bear the wafer and move the wafer according to a predetermined moving path;
a position measurement device, configured to obtain a position offset between an actual moving path of the movable stage and the predetermined moving path, wherein the position offset comprises a first dynamic position error and a second dynamic position error in a stage coordinate system, wherein the first dynamic position error and the second dynamic position error both vary with time, the stage coordinate system has a first stage axis and a second stage axis perpendicular to each other, and the first dynamic position error and the second dynamic position error are parallel to the first stage axis and the second stage axis, respectively; and
a control device, configured to control a timing for the light source to emit the incident light or control the image sensor to capture the reflected light according to the first dynamic position error and the second dynamic position error in real time in order to mitigate undesired effects caused by the position offset.
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