Patent ID: 8229588

Claim:
A method of advanced process control (APC) for semiconductor fabrication, comprising: providing a present wafer to be processed by a semiconductor processing tool; providing first data of previous wafers that have been processed by the semiconductor processing tool; decoupling noise from the first data to generate second data; evaluating an APC performance based on proximity of the second data to a target data; determining a control parameter based on the APC performance; and controlling the semiconductor processing tool with the control parameter to process the present wafer, wherein the control parameter includes a process time for a process, and wherein decoupling noise from the first data includes: identifying an APC impact on the first data to extract a chamber effect on the process, wherein the chamber effect includes a condition of the processing tool that can influence the process; and removing a pre-stage effect on the process, wherein the pre-stage effect includes a pre-stage influencing the process.