Etec Systems produces laser lithography equipment used to create photomasks needed for the manufacture of semiconductor chips. Since the etching process is not exact, there is some probability that any single geometry on a chip will be defective, which renders the entire wafer useless. This project investigated methods to improve estimates of the expected percentage of photomasks that will meet quality control criteria. These methods include investigation of certain parametric distributions to better fit machine calibration data, and the use of bootstrap techniques to improve the estimates of key parameters.