As the semiconductor device fabrication technology moving towards to the concept of cluster tools and single wafer processing, one of the major challenges that faces real-time process control is the development of suitable in-situ sensors to measure the critical process parameters. An in-situ sensor is proposed to measure one of the most critical parameters in many semiconductor processes, namely the vapor density of condensing species near the substrates. The proposed sensor combines the principles of atomic absorption spectros copy and atomic fluorescence spectros copy to provided the high sensitivity and wide dynamic range required in advanced semiconductor device fabrication processes . The technique is applicable to the control of material compositions, deposition rates, etching rates and process end point. The sensor can operate in ultra high vacuum environments as well as in process chambers of any pressure. It is non-intrusive, compact, robust and highly cost effective. Anticipated benefits/potential commercial applications - the proposed in-situ sensor would find immediate applications in many processes currently employed in the research or production of semiconductor devices. This in-situ monitoring technique is expected to offer not only better real-time control to a variety of processes but also a new tool for research in advanced device fabrication technology.Key words: in-situ sensor, real-time semiconductor process control.
