Patent ID: 7482180

Claim:
A method to analyze the warpage of organic laminates used in flip-chip packaging, the method comprising: providing a plurality of organic laminates, each laminate comprising a plurality of layers; collecting warpage data by measuring the warpage of each laminate; gathering thickness data by measuring layer thicknesses of each laminate at several different points of each laminate; performing a principal components analysis on the thickness data to calculate orthogonal basis vectors to re-express the thickness data in a different basis; projecting the thickness data for each laminate onto the orthogonal basis vectors; forming a linear model expressing the warpage data for each laminate in terms of the projection of corresponding thickness data onto the orthogonal basis vectors, each projection multiplied by a weight; analyzing the weights to determine the contribution of each orthogonal basis vector to the variance of the warpage data; and interpreting the contribution and structure of each orthogonal basis vector to estimate the importance of each layer or combination of layers in contributing to the warpage of the laminates.