If n_e and v_d are the number density of elec | vedclass

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(A) In a semiconductor,as the temperature increases,more covalent bonds break,leading to an increase in the number density of charge carriers $(n_e)$.

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$n_e$ increases and $v_d$ decreases

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(A) In a semiconductor,as the temperature increases,more covalent bonds break,leading to an increase in the number density of charge carriers $(n_e)$. Thus,$n_e$ increases.However,the drift velocity $(v_d)$ is given by the relation $v_d = \mu E$,where $\mu$ is the mobility. Mobility is inversely proportional to the relaxation time $(	au)$,which decreases as temperature increases due to more frequent collisions. Therefore,the mobility $\mu$ decreases,causing the drift velocity $v_d$ to decrease.Thus,$n_e$ increases and $v_d$ decreases.

If $n_e$ and $v_d$ are the number density of electrons and drift velocity in a semiconductor,respectively,what happens when the temperature is increased?

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