Liquid etch endpoint detection and process metrology

摘要

A semiconductor process endpoint detection system uses a relatively wide wavelength range of light to reflect off a semiconductor wafer being processed. Relatively narrow wavelength ranges can be monitored within this wide reflected wavelength range in order to produce an endpoint of the process. An indication can be produced which is a function of detected light intensities at multiple wavelength ranges. These indications aid in the determination of an endpoint of a process.