Limitations of MOSFET

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The theory of MOSFET as a barrier controlled device also brings to light some ultimate limits of a MOS device.

Minimum Energy for a switching event

It is known that minimum barrier energy required for a switching event in a MOS transistor is given by the formula –


The only variable in the equation for minimum energy is temperature. To analyse how the minimum energy required varies with the temperature, a graph of minimum energy against temperature is plotted.

Minimum channel length

Minimum switching time


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