Answer and Explanation:
Diffusion current can be defined as the current that flows as a result of diffusion of charge carriers in a semiconductor device as a result of difference in the concentration of holes and electrons in the both the regions (p and n) of the semiconductor device.
Depletion region of p-n junction is dominated by diffusion current.
The diffusion constant is directly proportional to the electron mobility and is given by the expression:
[tex]D_{c} = \Gamma ^{2} \mu ^{2} \tau [/tex]
where,
[tex]D_{c}[/tex] = Diffusion coefficient
[tex]\mu [/tex] = electron mobility
[tex]\tau [/tex] = time of correlation
Therefore, other parameters being constant (say):
[tex]D_{c}[/tex] is directly propotional to [tex]\mu ^{2}[/tex]
