Analysis of similarities between alarm events in the semiconductor manufacturing process

In the complex industry processes, failures occurred during manufacturing may deteriorate the final product quality, which results in a large number of scrapped products and thus a huge loss of the manufacturing Yield. To control the production steps, alarms go off to indicate occurred problems. However, alarms may be frequently raised which reduces the ability of operators to manage plant abnormalities. This paper deals with the study of correlation and the visualization of historical alarm data. Alarm events are mathematically represented as binary sequences, and two indices for identifying no critical alarms and similarities between alarms are proposed. An application on real industrial alarm data from the semiconductor manufacturing process has highlighted the practicability of the proposed approach in terms of reducing nuisance alarms, in order to decrease the operator overload.