VLSI (VELOCITY SATURATION)

 VELOCITY SATURATION:

it is proved that the velocity of charge carriers is linearly proportional to the electric field and the proportionality constant is called as mobility of the carrier. But when we increase the electric field beyond a certain velocity called the thermal velocity or saturated velocity the velocity of the charge carrier does not change with the electric field as shown in Figure below.

The electric field at which the velocity of the carrier saturates is called the critical electric field. The loss of energy is because of the collisions of carriers called as scattering effect.


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