Determination of back interface state distribution in fully depleted SOI MOSFETs

Two experimental techniques are proposed to extract the back interface state energy distribution of a silicon-on-insulator (SOI) film from the terminal characteristics of a fully depleted SOI MOSFET. The observed dependences of the MOSFET threshold voltage and subthreshold slope on substrate voltage are used to determine the density of back interface states (D/sub itb/) as a function of position in the bandgap. Data from fully depleted SIMOX n- and p-MOSFETs yield distributions of D/sub itb/ ranging from a high of approximately 10/sup 12/ cm/sup -2/ eV/sup -1/ near the n- and p-Fermi levels and decreasing below 10/sup 11/ cm/sup -2/ eV/sup -1/ near midgap.<
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