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Question: The mobility of hole in a semiconductor depend on (A) Electric field (B) Potential difference ...

The mobility of hole in a semiconductor depend on
(A) Electric field
(B) Potential difference
(C) Current
(D) Mass

Explanation

Solution

We must know that mobility of charge is the measure of how quickly a charge could move through a metal or semiconductor. It is directly proportional to the drift velocity of the charge through the conductor and inversely proportional to the applied electric field. We will obtain its unit from its formula by giving and equating the basic units of the factor it depends upon

Formula used:
μ=vdE\mu = \dfrac{{{v_d}}}{E}

Complete step by step solution:
We know that charge mobility in a conductor is the measure of the speed of the electron moving through a conductor or a semiconductor device under the influence of an applied external electric field. It is given as,
μ=vdE\mu = \dfrac{{{v_d}}}{E}
where, vd{v_d} is the drift velocity of the electron through the conductor, and EE is the electric field applied.
Mobility is frequently used in semiconductors to define the behaviour of carriers, whereas it is not much used in metals.
When carriers like electrons or holes in a material are accelerated due to an electric field but these carriers experience periodic collisions or scattering due to which the velocity of each carrier varies and becomes random. Now if we take the total average velocity of the electrons it will be proportional to the electric field and this proportionality constant is nothing but mobility. Mobility depends on many parameters like the temperature, the number of impurities in the crystal, and the quality of a semiconductor crystal. The mobility of electrons is always greater than that of holes.
Based on the above discussion and the given options we can say that the mobility of a hole in a semiconductor depends on the Electric field.
Hence, the correct answer is option (A) Electric field.

Note:
For these types of questions we must know about basic semiconductor physics like what is a P-type and N-type semiconductor, diffusion and drift mechanism, mobility and conductivity, etc. we also need to know their expression and how to find them.