Patent Document ID: 20030028279
Application ID: 09826929
Patent Flag: 0

Claim One:
1. A method for determining efficient parameters in chemical-mechanical polishing processes comprising the steps of: a. using a Taguchi experiment to lead the CMP procedure and determine essential parameters to calculate a maximum material rate (MRR) and the within wafer non-uniformity (WIWNU), wherein four essential coefficients are picked out as changeable parameters and adjusted during the experiment and a polishing time is set to be a fifth parameter to complete a model, each parameter is tested under different levels to calculate the (MRR) and the (WIWNU); b. analyzing S/N ratios of the MRR and the WIWNU, wherein the S/N ratios of the MRR and the WIWNU in each trial are calculated and used to make response tables and response figures, and then analysis of variance (ANOVA) is employed in estimating contributing degrees of each parameter to decide a parameter set of the MRR and the WIWNU; c. establishing the CMP process with the parameter set of the MRR and the WIWNU, wherein a neural network simulates the CMP procedure and optimize the parameter automatically, data of step A are a training samples of the neural network, wherein a standard deviation of t 2 ( &sgr;t 2 ) after polishing and the MR are outputs and then define a performance index includes the MRR and the &sgr;t 2, said performance index is optimum in its largest mode; and d. optimizing the parameters set of the CMP procedure, wherein the neural network based CMP model in step C is used in this step and has a fine-tuning function to modify each parameter of the parameter set to be the best ones, and then a optimum parameter set is obtained.