Gage repeatability and reproducibility (GRR) is widely used to evaluate the accuracy of measuring instruments. However, GRR analysis is often overlooked in engineering work. Therefore, in order to improve engineering quality and efficiency, a systematic GRR study must be implemented. This article focuses on the innovative application of GRR in Applied Materials' metrology tools and process optimization, and successfully solves the customer's HVP . 1: GRR analysis of EPI resistivity measurement tools : Resistivity ( RS ) is a key parameter of EPI films, and the stability of the current measurement system seriously affects the identification and development of EPI processes. After GRR analysis, the P/T ratio is 172% ( >30% ). Subsequent analysis shows that the reason for the poor GRR performance is the poor repeatability of the tool measurement. Next, after performing Pair-T tests on parts tested at different times and creatively using IMR graphs to group and analyze the resistance of the inner and outer circles of the wafer, it was found that the reason for the poor repeatability was the degradation of the wafer during the test process and the different oxide layer thickness and charge uniformity inside and outside the wafer, which was caused by the current RS measurement system. Based on the above experimental analysis, an improvement plan for optimizing the measurement tool is proposed, and subsequent optimization is in progress. 2: Application of GRR in monitoring the capture rate ( CR ) of wafer optical inspection equipment: Currently, the capture rate monitoring method of wafer optical inspection equipment has not been qualified . Therefore, it is necessary to use GRR analysis to qualify the effectiveness of the current monitoring method and the drift of the tool during the monthly warranty period. The results show that the current monitoring method is effective ( P/T=17% ) and the machine has no drift problem during the monthly warranty period. The project also analyzed the root cause of the large P/T ratio ( > 10% ). The results show that due to the limitation of the machine's own capabilities, the machine has detection repeatability problems in the detection of specific 100nm protrusions and intrusion defects. Through this study, it was found that GRR analysis of the number of defects alone is not enough to monitor the performance of the current machine. Attribute GRR analysis of the most challenging defect types is required , which will be a new direction for scientific inspection equipment performance monitoring. 3 : GRR analysis of the effect of measurement time on silicon dioxide thickness : The thickness of silicon dioxide produced by thermal oxidation will increase over time. If the measurement time is not selected properly, it will seriously affect the measurement results. After GRR analysis, it was found that the current measurement time interval and method met the requirements ( P/T ratio = 9% ). Then the possible ways to improve the process specifications were further studied . The results showed that under the current measurement GRR capability, the process specifications can be further improved and reduced to 40% of the original , while the P/T ratio can be maintained at 15% . Finally, through the ICC , P/T and Cp chart platforms, a systematic method for continuous improvement of processes and GRR capabilities was developed to provide guidance for continuous optimization of GRR and processes. The successful implementation of the GRR project made the entire team realize the importance of GRR in measurement tool monitoring and process optimization, and based on the research of the above projects, the team formulated an improvement plan for the implementation of GRR BKM, laying a solid foundation for improving the quality and efficiency of the project.
