Consumption Optimization in CMP Processes

Abstract

This paper introduces a method of minimizing consumption in order to reduce the running cost of oxide-film CMP processes. Three types of consumables are administrated and replaced based on control limits in use time and monitored removal rate. Typically the control limits are determined separately by consumable. However the combination of consumables' use times takes various effects on removal rate. Therefore, a control limit optimization method to minimize the cost under the condition of removal rate in run-to-run lot works, wherein product lots are processed consecutively on the equipment, is developed. To achieve this, the within-wafer removal rate is modeled based on the use time of consumables, and a run-to-run simulation method to summarize consumption has been developed. The results show that this method could find a new control limit, which reduces the manufacturing cost.