Multiple Choice Questions and Answers on Semiconductor Theory
Q11. A pentavalent impurity has ………. Valence electrons
- 3
- 5
- 4
- 6
Answer : 2
A12. An n-type semiconductor is ………
- Positively charged
- Negatively charged
- Electrically neutral
- None of the above
Answer : 3
Q13. A trivalent impurity has ….. valence electrons
- 4
- 5
- 6
- 3
Answer : 4
A14. Addition of trivalent impurity to a semiconductor creates many ……..
- Holes
- Free electrons
- Valence electrons
- Bound electrons
Answer : 1
Q15. A hole in a semiconductor is defined as …………….
- A free electron
- The incomplete part of an electron pair bond
- A free proton
- A free neutron
Answer : 2
Q16. 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
Answer : 2
Q17. As the doping to a pure semiconductor increases, the bulk resistance of the semiconductor ………..
- Remains the same
- Increases
- Decreases
- None of the above
Answer : 3
Q18. 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
Answer : 2
Q19. In a semiconductor, current conduction is due to ……..
- Only holes
- Only free electrons
- Holes and free electrons
- None of the above
Answer : 3
Q20. The random motion of holes and free electrons due to thermal agitation is called ……….
- Diffusion
- Pressure
- Ionisation
- None of the above
Answer : 1