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If a small amount of antimony is added to germanium crystal
A
Its resistance is increased
B
It becomes a p-type semiconductor
C
The antimony becomes an acceptor atom
D
There will be more free electrons than holes in the semiconductor
Detailed Solution
Antimony is a pentavalent element (5 valence electrons); germanium is tetravalent.
Four of the electrons of antimony form covalent bonds with neighbouring germanium atoms and the fifth electron is donated as a free electron.
So antimony is a donor atom and the crystal becomes an n-type semiconductor.
In an n-type semiconductor electrons are the majority carriers, so there are more free electrons than holes.
Doping increases the number of charge carriers, so the resistance decreases, not increases.
Hence there will be more free electrons than holes in the semiconductor.
Four of the electrons of antimony form covalent bonds with neighbouring germanium atoms and the fifth electron is donated as a free electron.
So antimony is a donor atom and the crystal becomes an n-type semiconductor.
In an n-type semiconductor electrons are the majority carriers, so there are more free electrons than holes.
Doping increases the number of charge carriers, so the resistance decreases, not increases.
Hence there will be more free electrons than holes in the semiconductor.