A new method for electrically measuring thin-film thickness of SOI MOSFETs

The authors have developed a method for electrically measuring the silicon film thickness and the back oxide thickness of thin-film silicon-on-insulator (SOI) MOSFETs. These film thicknesses can be determined from the dependence of threshold voltage on back gate voltages. This method has good accuracy because of the consideration of the carrier distribution, and the consistency of the threshold voltage definition in both measurement and analysis. The calculated Si thickness of a double-gate SOI MOSFET agrees well with the thickness measured from a cross-sectional SIM (scanning ion microscopy) image.<
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