Patent ID: 9430593
Filing Date: 2016-08-30
CPC Classification: G06F,H01L

Claim Text:
1. A computer implemented method for providing in-plane distortion (IPD) prediction, the method comprising: (a) generating a plurality of sample wafer shapes, the plurality of sample wafer shapes generated by varying a set of coefficients B in a predefined shape equation; (b) performing finite element (FE) model based IPD prediction for the plurality of sample wafer shapes, wherein IPD predictions with respect to x-axis (X-IPD) and IPD predictions with respect to y-axis (Y-IPD) are obtained for the plurality of sample wafer shapes; (c) fitting equations to the FE model based X-IPD predictions and the FE model based Y-IPD predictions for the plurality of sample wafer shapes to obtain a set of coefficients A, wherein the set of coefficients A corresponds to the set of coefficients B of the shape equation used in step (a) to generate the plurality of sample wafer shapes; (d) analyzing the set of coefficients B and the set of coefficients A to determine a mapping function ƒ suitable for calculating coefficients A based on coefficients B of the shape equation; (e) calculating an interim shape for a given wafer utilizing the mapping function ƒ and a shape equation representing the initial shape of the given wafer; and (f) performing IPD prediction for the given wafer based on the interim shape calculated for the given wafer.