Subsurface material characterization using high frequency eddy current spectroscopy

New processes introduced by nano science into much more conventional industrial applications require fast, robust and economical reasonable inspection methods for process control and quality assurance. Developed for semiconductor industries the methods available for thin film characterization and quality control are often complex and require highly skilled operation personnel. This paper presents a new concept based on high frequency eddy current spectroscopy that allows reliable and robust thickness measurements of thin conducting films on silicon or insulation substrates with a thickness resolution of about 2.5 nm. The transmission mode sensor configuration is a more practical method for inlinemonitoring of thin film characterization. Due to the insensitivity of the transmission mode to dislocations or slight tilting of the sample the high frequency eddy current method is a practical method for thin film characterization in the industrial environment.