Automated metrology qualification strategy [IC measurement]

This paper presents the methodology used to perform qualification of critical dimension (CD) SEM (Scanning Electron Microscope) tools for sub-0.5 /spl mu/m process control. A submicron pitch standard has been characterized and incorporated into an automated tool calibration and qualification procedure. After first matching individual tools to the standard, daily tool qualification is performed on a CD qualification wafer. SPC (Statistical Process Control) charts are set up to subtract line broadening effects encountered in repeated SEM measurement. The automated calibration and qualification procedures described here permit accurate measurements to be provided as is required for effective metrology support of the modern factory.