A novel push-pull sampling methodology for test production in semiconductor manufacturing industries

This paper describes the use of a push-pull sampling methodology on test products to improve manufacturing efficiency. The conventional test technologies heavily rely on manufacturing operators to manually input the necessary information to a station controller for processing a test lot. This approach has resulted in some quality issues of sampling miscalculation owing to under-sample requirements in test processes. A robust solution is developed by applying a two-stage push-pull methodology in a new automated sampling system. The push-pull approach of automated sampling controls and propagates the correct sampling data to the operators for them to run test lots with the correct samples. The system has contributed to improving manufacturing capacity, creating robust controllable system, reducing human handling or dependency, and shortening the lead time to end customers. All these have resulted in effective manufacturing control to eliminate non-value added activities and zero repeated quality cases in the manufacturing test environment. The overall ROI (return of investment) realized by this system is a cost saving of million dollars, by mitigating the cost of human errors against reduction of production cost per unit.