Systems, methods and computer program products for detecting the position of a new alignment mark on a substrate based on fitting to sample alignment signals

A method of detecting a position of a new alignment mark on a substrate, the method comprising the steps of:

• providing an alignment signal model;
• generating a new alignment signal from the new alignment mark;
• and
• fitting the new alignment signal to the alignment signal model to thereby identify the position of the new alignment mark on the substrate.

A system for detecting a position of a new alignment mark on a substrate comprising:

• means for obtaining a plurality of sample alignment signals from a plurality of sample alignment marks, and a new alignment signal from the new alignment mark;
• means for producing an alignment signal model from the plurality of sample alignment signals;
• and
• means for fitting the new alignment signal to the alignment signal model to thereby identify the position of the new alignment mark on the substrate.

A computer program product for determining a position of a new alignment mark on a substrate, the computer program product comprising a computer-readable storage medium having computer-readable program code means embodied in the medium, the computer-readable program code means comprising:

• computer-readable program code means for obtaining a plurality of sample alignment signals from a plurality of sample alignment marks, and a new alignment signal from the new alignment mark;
• computer-readable program code means for producing an alignment signal model from the plurality of sample alignment signals;
• and
• computer-readable program code means for fitting a new alignment signal to the alignment signal model to thereby identify the position of the new alignment mark on the substrate.