176. The conduction band is
A. always located at the top of the crystal.
B. also called the forbidden energy gap.
C. a range of energies corresponding to the energies of the free electrons.
D. not an allowed energy band.
177. The forbidden energy gap in semiconductors
A. lies just below the valence band.
B. lies just above the conduction band.
C. lies between the valence band and the conduction band.
D. is the same as the valence band.
178. At absolute Zero temperature, all the valence electrons in an intrinsic semiconductor are
A. in the valence band.
B. in the forbidden gap.
C. in the conduction band.
D. free electrons.
179. In a p-type semiconductor
A. the number of holes equals the number of free electrons
B. holes are the majority carriers.
C. the forbidden energy gap is Zero
D. the impurity is a donor impurity.
180. In n-type germanium
A. forbidden energy gap is greater than in n-type silicon.
B. impurity has three valence electrons.
C. number of holes equals the number of free electrons
D. the holes are minority carriers.
181. The energy required to break a covalent bond in a semiconductor
A. is equal to leV.
B. by majority carriers only.
C. by minority carriers only.
D. mostly by the movement of holes.
182. Current flow in a p-type semiconductor is
B.(c) the antimony becomes an acceptor impurity.
C.(d) there will be more free electrons than holes in the semiconductor.
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