CMP PROCESS INVOLVING FREQUENCY ANALYSIS-BASED MONITORING

摘要

The invention provides a method for monitoring a chemical-mechanical polishing process, comprising receiving a real-time data signal from a chemical-mechanical polishing process, wherein the real-time data signal pertains to a frictional force, torque, or motor current, converting the data signal into a power spectrum of signals with different frequencies whose sum equals that of the original data signal, identifying and monitoring the signal components of the power spectrum corresponding to an aspect of the chemical-mechanical polishing process, detecting a change in the amplitude or frequency of the signal component, and altering the chemical-mechanical polishing process in response to the detected change. The invention also provides an apparatus for carrying out the aforementioned method.