Q.1
Addition of pentavalent impurity to a semiconductor creates many
  • Free electrons
  • Holes
  • Valence electrons
  • Bound electrons
Q.2
A pn junction acts as a ___________
  • Controlled switch
  • Bidirectional switch
  • Unidirectional switch
  • None of the above
Q.3
At room temperature, an intrinsic silicon crystal acts approximately as
  • A battery
  • A conductor
  • An insulator
  • A piece of copper wire
Q.4
At absolute temperature, an intrinsic semiconductor has ___________
  • A few free electrons
  • Many holes
  • Many free electrons
  • No holes or free electrons
Q.5
A reverse biased pn junction has resistance of the order of
  • Ω
  • kΩ
  • MΩ
  • None of the above
Q.6
A pentavalent impurity has ___________ Valence electrons
  • 3
  • 5
  • 4
  • 6
Q.7
A hole and electron in close proximity would tend to ___________
  • Repel each other
  • Attract each other
  • Have no effect on each other
  • None of the above
Q.8
The impurity level in an extrinsic semiconductor is about of pure semiconductor.
  • 10 atoms for 108 atoms
  • 1 atom for 108 atoms
  • 1 atom for 104 atoms
  • 1 atom for 100 atoms
0 h : 0 m : 1 s