Coupon Accepted Successfully!


Intrinsic Semiconductors

  • A pure semiconductor is called intrinsic semiconductor. It has thermally generated current carriers.
  • Intrinsic semiconductors have four electrons in the outermost orbit of atom and atoms are held together by covalent bond.
  • Free electrons and holes both are charge carriers and ne (in CB) = nh (in VB)
  • The drift velocity of electrons (ve) is greater than that of holes (vh). For them fermi energy level lies at the center of the CB and VB
  • In pure semiconductor, impurity must be less than 1 in 108 parts of semiconductor.
  • In intrinsic semiconductor, n(o)e = n(o)h = ni, where n(o)e = electron density in conduction band, n(o)h = hole density in VB, ni = density of intrinsic carriers.
  • The fraction of electrons of valance band present in conduction band is given by 106972.png; where Eg = Fermi energy or k = Boltzmann’s constant and T = Absolute temperature
  • Because of less number of charge carriers at room temperature, intrinsic semiconductors have low conductivity so they have no practical use.
  • Number of electrons reaching from valence band to conduction band, 106978.png

Test Your Skills Now!
Take a Quiz now
Reviewer Name