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In this thesis, the basic device physics of a buried chan- nel n-MOSFET are described, which include the threshold-volta- ge model and I-V characteristics. Based on these models, the extraction methods for the device parameters including the de- vice structure parameters and the material parameters are pre- sented. The device structure parameters include effective cha- nnel length, channel doping profile, and source/drain doping profile and its junction depth. The material parameters inclu- de the parameters in the mobility model. Using these extracted parameters, we can simulate the electrical characteristics of the fabricated buried channel n-MOSFET's by using a two-dimen- sional numerical MOSFET simulator ( SUMMOS ). It is shown that good agreements between simulation results and experimental data are obtained for wide ranges of applied biases and chann- el lengths. Based on the simulation, the drain-induced barrier loweri- ng and punch-through effects of short-buried-channel n-MOS- FET's are discussed, and the methods for improving these short-channel effects are proposed.
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