METHOD AND APPARATUS FOR IN-SITU MONITORING OF PLASMA ETCHING AND DEPOSITION PROCESSES USING PULSED BROADBAND LIGHT SOURCE

摘要

PROBLEM TO BE SOLVED: To provide a method and apparatus for monitoring a plasma etching or deposition process that reduces the sensitivity of a detector to fluctuations in plasma emission, has a sufficient signal to noise ratio, and allows for measurements over a broad range of wavelengths.SOLUTION: The present invention describes an interferometric method and an apparatus for in-situ monitoring of a thin film thickness and of etching and deposition rates of the thin film using a flash lamp providing a high instantaneous power pulse and having a wide spectral width. The optical path between the flash lamp and a spectrograph used for detecting light reflected from a wafer is substantially transmissive to an ultraviolet range of the spectrum. Software algorithms calculate film thickness and etching and deposition rates.