Patent ID: 8555235

Claim:
A computer-implemented method of determining changes in design attributes, the method comprising: determining, by a computer, based on at least a predetermined value of a parameter resulting from fabrication of an integrated circuit, a first value of a design attribute for at least one stage in a design of the integrated circuit, wherein the at least one stage comprises at least one cell and at least one interconnect coupled thereto; applying, by the computer, an estimation technique on the at least one stage, at the predetermined value of the predetermined parameter, to obtain a second value of the design attribute; determining a calibration function based on the first value of the design attribute and the second value of the design attribute, the calibration function configured to receive an estimated value of the design attribute and return a calibrated estimate having a more accurate value of the design attribute compared to the estimated value for the predetermined value of the predetermined parameter; repeatedly applying the estimation technique to each of a plurality of additional values of the predetermined parameter, to obtain a corresponding plurality of additional second values of the design attribute; repeatedly performing on each additional second value of the design attribute, the calibration function, to obtain a plurality of calibrated estimates of the design attribute; and storing in memory the plurality of calibrated estimates of the design attribute.