Material Science - Semiconductor Physics

1. Current flow in a semiconductor depends on the phenomenon of
(a) drift
(b) diffusion
(c) recombination
(d) all of the above.

2. The process of adding impurities to a pure semiconductor
is called
(a) mixing
(b) doping
(c) diffusing
(d) refining.

3. The most widely used semiconducting material in electronic devices is
(a) germanium
(b) silicon
(c) copper
(d) carbon

4. Electron-hole pairs are produced by
(a) recombination
(b) thermal energy
(c) ionization
(d) doping

5. Recombination takes place when
(a) an electron falls into a hole
(b) a positive and a negative ion bond together
(c) a valence electron becomes a conduction
(d) a crystal is formed

6. When a P-N junction is formed, diffusion current causes
(a) mixing of current carriers
(b) forward bias
(c) reverse bias
(d) barrier potential.

7. The leakage current of a P-N diode is caused by
(a) heat energy
(b) chemical energy
(c) barrier potential
(d) majority carriers.

8. Electronic components which are made of a semiconductor material are often called
⸺ devices.
(a) solid-state
(b) silicon
(c) germanium
(d) intrinsic.

9. Any voltage that is connected across a P-N junction is called ⸺ voltage.
(a) breakdown
(b) barrier
(c) bias
(d) reverse.

10. The area within a semiconductor diode where no mobile current carriers exist when it is
formed is called ⸺ region.
(a) depletion
(b) saturation
(c) potential barrier
(d) space charge.


    1. (d)     2. (b)     3. (b)     4. (b)    5. (a) 
    6. (d)     7. (a)     8. (a)     9. (c)     10. (a)