Monitoring of a sampled process data under Run-to-Run control: application to a semiconductor process

This paper deals with a technical issue in the semiconductor industry which is the monitoring of a regulated process subject to various sampling frequencies. A mathematical link between the variance of the fully sampled and the partially sampled process is established based on the sampling rate value. Moreover, a method is proposed in order to adapt the monitoring limits to the sampling rate so that fault detection becomes more efficient. The pertinence of the method is tested using real data provided by a semiconductor foundry.