Tool induced shift reduction determination for overlay metrology

摘要

One embodiment relates to a method for semiconductor workpiece processing. In this method, a baseline tool induced shift (TIS) is measured by performing a baseline number of TIS measurements on a first semiconductor workpiece. After the baseline TIS has been determined, the method determines a subsequent TIS based on a subsequent number of TIS measurements taken on a first subsequent semiconductor workpiece. The subsequent number of TIS measurements is less than the baseline number of TIS measurements.

主权项

1. A method for measuring tool induced shift (TIS), comprising:
positioning a moveable stage having a semiconductor workpiece thereon so that a field of view (FOV) of an imaging system corresponds to a first alignment mark on the semiconductor workpiece; stepping an imaging device of the imaging system through a plurality of different positions along an optical axis, wherein the plurality of different positions corresponds a plurality of different optical angles, respectively; for each of the plurality of different positions, changing a directional orientation of the semiconductor workpiece from a first angular orientation to a second angular orientation, wherein the first and second angular orientations are measured with respect to a first diametric axis extending through the semiconductor workpiece; and measuring a first plurality of overlay offsets, respectively, for the plurality of optical angles at the first and second angular orientations for the first alignment mark.