Home
Class 12
PHYSICS
In a pure silicon (n(i)=10^(16)//m^(3)) ...

In a pure silicon `(n_(i)=10^(16)//m^(3))` crystal at `300K, 10^(21)` atoms of phosphorus are added per cubic meter. The new hole concentration will be

A

`10^19 "per m"^3`

B

`10^11 "per m"^3`

C

`10^5 "per m"^3`

D

`10^21 "per m"^3`

Text Solution

Verified by Experts

The correct Answer is:
B
For intrinsic semiconductor, `n_i=10^16//m^3`and `n_h=n_e` and when phosphorus (pentavalent impurity) is added, it becomes an n-type semiconductor.
`because n_e=10^21//m^3`
`therefore n_h=n_i^2/n_e=(10^16xx10^16)/10^21=10^11//m^3`
Promotional Banner

Topper's Solved these Questions

  • ROTATIONAL MOTION

    MARVEL PUBLICATION|Exercise TEST YOUR GRASP - 3|8 Videos

  • STATIONARY WAVES

    MARVEL PUBLICATION|Exercise TEST YOUR GRASP-8|20 Videos

Similar Questions

Explore conceptually related problems

In a pure silicon (n_(i)=10^(16)m^(-3)) crystal at 300 K, 10^(23) atoms of phosphorus are added per cubic meter. The new whole concentration will be

If resistivity of pure silicon is 3000Omegam , and the electron and hole mobilities are 0.12 m^(2)V^(-1)s^(-1) and 0.045m^(2)V^(-1)s^(-1) respectively, determine the resistivity of a specimen of the material when 10^(19) atoms of phosphorous are added per m^(3) are also added. Given charge on electron =1.6xx10^(-19)C .

In sample of pure silicon 10^(13) "atom"//cm^(3) is mixed of phosphorus. If all doner atoms are active then what will be resistivity at 20^(@)C if mobility of electron is 1200 cm^(2)//"Volt" sec :-

Pure Si crystal at 300 k has 2.5 xx10^(28) atoms m^(-3) it is doped by 1 ppm concentration of pentavalent element As calculate the new concentration of electrons and holes take n_(i) =1.5 xx10^(16) m^(-3)

The product of the hole concentration and the conduction electron concentration turns out to be independent of the amount of any impurity doped. The concentration of conduction electrons in germanium is 6xx10^19 per cubic per cubic metre.When some phosphorus impurity is doped into a germanium sample, the concentration of conduction electrons increases to 2xx10^28 per cubic metre.Find the concentration of the holes in the doped germanium.

MARVEL PUBLICATION-SEMICONDUCTORS -MCQs
  1. Intrinsic semiconductor is electrically neutral. Extrinsic semiconduct...

    Text Solution

    |

  2. The maximum wavelength of electromagnetic radiation, which can create ...

    Text Solution

    |

  3. In a pure silicon (n(i)=10^(16)//m^(3)) crystal at 300K, 10^(21) atoms...

    Text Solution

    |

  4. There are two Ge crystals A and B. Few aluminium atoms are added to A...

    Text Solution

    |

  5. By increasing the temperature , the specific resistance of a conductor...

    Text Solution

    |

  6. In semiconductors at a room temperature

    Text Solution

    |

  7. Which of the following , when added as an impurity, into the silicon, ...

    Text Solution

    |

  8. A semiconductor has phosphorus as impurity, then it will have

    Text Solution

    |

  9. The conductivity of a semiconductor increases with increase in tempera...

    Text Solution

    |

  10. In a P -type semi-conductor, germanium is dopped with

    Text Solution

    |

  11. Carbon , silicon and germanium have four valence elcectrons each . The...

    Text Solution

    |

  12. The electrical conductivity of a semiconductor increases when electrom...

    Text Solution

    |

  13. In the energy band diagram of a material shown below, the open circles...

    Text Solution

    |

  14. A silicon specimen is made into a P-type semiconductor by dopping, on ...

    Text Solution

    |

  15. The energy gap of silicon is 1.14 eV. The maximum wavelength at which ...

    Text Solution

    |

  16. A Ge specimen is dopped with Al. The concentration of acceptor atoms i...

    Text Solution

    |

  17. if n(e) and v(d) be the number of electrons and drift velocity in a se...

    Text Solution

    |

  18. When a potential difference is applied across, the current passing thr...

    Text Solution

    |

  19. A P-type sillicon semiconductor is made by adding one atom of indium p...

    Text Solution

    |

  20. Pure Si at 500K has equal number of electron (n(e)) and hole (n(h)) co...

    Text Solution

    |