Home
Class 12
PHYSICS
The number density of electrons and hole...

The number density of electrons and holes in pure silicon at `27^@` C are equal and its value is `2.0 xx 10^16 m^(-3)`. On doping with indium the hole density increases to `4.5xx 10^22 m^(-3)`, the electron density in doped silicon is

A

`10xx10^9 m^(-3)`

B

`8.89xx10^9 m^(-3)`

C

`11xx10^9 m^(-3)`

D

`16.78xx10^9 m^(-3)`

Text Solution

Verified by Experts

The correct Answer is:
B
Using , `n_e=n_i^2`
Here, `n_i=2xx10^16 m^(-3) , rho=4.5xx10^22 m^(-3)`
`therefore n=n_i^2/rho=((2xx10^16)^2)/(4.5xx10^22)=8.89xx10^9 m^(-3)`
Promotional Banner

Topper's Solved these Questions

  • SEMICONDUCTOR ELECTRONICS : MATERIALS , DEVICES AND SIMPLE CIRCUITS

    NCERT FINGERTIPS|Exercise P-N Junction|6 Videos

  • SEMICONDUCTOR ELECTRONICS : MATERIALS , DEVICES AND SIMPLE CIRCUITS

    NCERT FINGERTIPS|Exercise Semiconductor Diode|12 Videos

  • SEMICONDUCTOR ELECTRONICS : MATERIALS , DEVICES AND SIMPLE CIRCUITS

    NCERT FINGERTIPS|Exercise Intrinsic Semiconductor|6 Videos

  • RAY OPTICS AND OPTICAL INSTRUMENTS

    NCERT FINGERTIPS|Exercise Assertion And Reason|15 Videos

  • WAVE OPTICS

    NCERT FINGERTIPS|Exercise Assertion And Reason|15 Videos

Similar Questions

Explore conceptually related problems

The number densities of electrons and holes in a pure germanium at room temperature are equal and its value is 2xx 10^(16) per m^(3) . On doping with aluminium the hole density increases to 3.5 xx10^(22) per m^(3) , then the electron density in doped germanium is

The density of an electron-hole pair in a pure germanium is 3xx 10^(16) m^(-3) at room temperature. On doping with aluminium, the hole density increases to 4.5 xx 10^(22) m^(-3) . Now the electron density ( in m^(-3)) in doped germanium will be

In a semiconductor, the number density of intrinsic charge carriers at 27^@C is 1.5 xx 10^(16) // m^3 . If the semiconductor is doped with impurity atom, the hole density increase to 4.5 xx 10^(22)//m^3 . The electron density in the doped semiconductor is "_______" xx 10^(9)//m^3 .

Find the hole density in doped silicon if at 27^(@) c the electron density and hole density are equal nd equal to 3.0 xx10^(16) on doping with arsenic electron density increases to 9xx10^(19) m^(-3)

A semiconductor has equal electron and hole concentration of 2xx10^(8)m^(-3) . On doping with a certain impurity, the electron concentration increases to 4xx10^(10)m^(-3), then the new hole concentration of the semiconductor is