Pure Si at 500 K has equal number of electron (ne) and hole (nh) concentrations of 1.5 1016 m-3. Doping by indium increases nh to 4.5 1022 m-3. The doped semiconductor is of
- p-type having electron concentration ne = 5 109 m-3
- n-type with electron concentration ne = 5 1022 m-3
- p-type with electron concentration ne = 2.5 1010 m-3
- n-type with electron concentration ne = 2.5 1023 m-3
Answer
(1) p-type having electron concentration ne = 5 109 m-3
Solution
Indium (group 13) is a trivalent acceptor the doped semiconductor is p-type.
Mass action law: ne nh = ni2
ne = (1.5 1016)24.5 1022 = 2.25 10324.5 1022
= 5 109 m-3
Answer: (1)