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The MOSFET performance mainly depends on ON and OFF state conditions depending on the different applied bias voltage. The performance analysis is categorized as:

1 a) DC AnalysisIn DC analysis, subthreshold parameters are mainly calculated such as IOFF, DIBL, SS, and threshold voltage (Vth). These parameters can be defined as:i) IOFF: It is OFF-state current when the applied gate voltage (Vgs) is less than the threshold voltage (Vth).ii) Vth: It the required minimum value of the gate voltage to establish channel inversion.iii) Subthreshold Slope (SS): It is one of SCE that can be derived from the equation:(1.1)iv) Drain induced barrier lowering (DIBL): DIBL is another important parameter of SCE which is a measure of threshold voltage variations with the variation in drain voltage for constant drain current. It can be derived from the equation:(1.2)

2 b) AC analysisAC analysis is dependent on frequency of applied bias voltages. The important ac parameters are:i) Transistor Capacitance (Cg): There are several inherent capacitances such as gate to source, the gate to drain and gate to body capacitances. Transistor capacitances are important for desired switching behavior from OFF to ON state.ii) Transconductance (gm): It is a measure of drain current with the variation in gate voltage for constant drain current. It plays an important role to achieve high value of transistor amplifier gain. It can be derived from the equation:(1.3)

3 c) Electrostatic CharacteristicsThere are a few other important parameters that also have significant importance of MOSFET behavior during ON/OFF state. Energy band diagram, channel potential, electric field distribution and electron-hole density are important electrostatic properties that need to be analysed while designing any MOSFET architecture.