A Multi-step Wafer-level Run-to-Run Controller with Sampled Measurements for Furnace Deposition and CMP Process Flows APC: Advanced Process Control

摘要

This paper describes a multi-step Run-to-Run controller design for a class of furnace deposition and CMP process flows. The wafer-to-wafer thickness variation introduced by the furnace deposition process has been compensated for by a wafer-level CMP controller. To avoid measuring all wafers in a lot and to reduce metrology cost, knowledge of upstream furnace process was employed and a piecewise linear function has been utilized to interpolate missing metrology data. Results are shown to illustrate the effectiveness of the described control method.