The conductivity of a semiconductor increases with increasein temperat

1.	The conductivity of a semiconductor increases with increasein temperature because
Answer» number density of free current carriers increases. relaxation time increases. both nomber density of carriers and relaxation time increase. number density of current carriers increases,relaxation time decreases but effect of decreasein relaxation time is MUCH less than increase in number density. Solution :number density of current carriers increases,relaxation time decreases but effect of decreasein relaxation time is much less than increase in number density. As TEMPERATURE is increased, large no. of charge carriers transit from valence band to CONDUCTION band. Thus, free chargecarrier density is increased and so electrical conductivityof SEMICONDUCTOR increases considerably. This is the DOMINATING factor for increase in electrical donductivity of semiconductors.

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The conductivity of a semiconductor increases with increasein temperature because

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