本题目来源于试卷: 美国2021年物理杯赛真题 PHYSICS BOWL 2021，类别为 美国物理杯赛(Physics Bowl)
[单选题]
A P-type semiconductor is doped to produce one of the following. What will it produce:
A. both holes and electrons
B. positive electrons
C. negative electrons
D. holes
E. positive protons
参考答案: D
本题详细解析:
In a pure (intrinsic) Si or Ge semiconductor, each nucleus uses its four valence electrons
to form four covalent bonds with its neighbors and there are no excess electrons or
holes. Now, if one of the atoms in the semiconductor lattice is replaced by an element
with three valence electrons, such as a Group 3 element like Boron (B) or Gallium (Ga),
the electron-hole balance will be changed.
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