JEE Class main Answered
Derive the expression of current density and Mobility of charge carriers for semiconductor
Asked by jeetendrarajpoot818 | 08 Jun, 2022, 10:10: PM
Expert Answer
Current density J = n e vd
where n is number density of charge carriers , e is unit charge and vd is drift velocity
In semiconductor, we have two types of charge carriers , electron in conduction band and hole in valance band
Let ne be the number of electrons per unit volume in conduction band .
Let nh be the number of holes per unit volume in valance band .
Current density J = ( ne e vde + nh e vdh )
where vde is drift velocity of electron and vdh is drift velocity of hole .
Drift velocity is related to mobility as follows
vde = μe E and vdh = μh E
where μe is mobility of electron , μh is mobility of hole and E is electric field .
Current density J = ( ne e μe + nh e μh ) E
----------------------------
In intrinsic semiconductor , there are equal number of electrons and holes
ne = nh = n
In intrinsic semiconductor , Current density J = n e ( μe + μh ) E
In n-type semiconductor , ne > > nh
In n-type semiconductor , Current density J = ne e μe E
In p-type semiconductor , nh > > ne
In p-type semiconductor , Current density J = nh e μh E
Answered by Thiyagarajan K | 09 Jun, 2022, 09:08: AM
JEE main - Physics
Asked by arunmohan23 | 21 Jun, 2022, 11:25: AM
ANSWERED BY EXPERTJEE main - Physics
Asked by jeetendrarajpoot818 | 08 Jun, 2022, 10:10: PM
ANSWERED BY EXPERTJEE main - Physics
Asked by sairayallugokul | 03 Nov, 2021, 10:55: PM
ANSWERED BY EXPERTJEE main - Physics
Asked by Varshil | 24 Apr, 2019, 07:43: AM
ANSWERED BY EXPERT
