Dynamic Feedback Recipe in CMP Production line

摘要

Conventionally wafers are run under a fixed recipe: variables input including slurry chemicals, flow rate, temperature, backside pressure and mechanical parameters, etc. regardless of the deterioration of pad profile, backing film and related consumables. This simplifies the CMP polishing procedure in the production line at the cost of yield loss. However, because of the variation of pad profile during polishing, pad deterioration worsens the uniformity nonlinearly in the processing. In order to solve the above issue, a dynamic recipe for compensating the pad profile variation is investigated in this study. The result shows that a suitable feedback mechanism in backside pressure can improve the within-wafer non-uniformity significantly.