NTA Abhyas JEE Main2020PhysicsSemiconductorsPractice
A silicon specimen is made into a p -type semiconductor by doping, on an average, one indium atom per 5 × 10 7 silicon atoms. If the number density of atoms in the silicon specimen is 5 × 10 28 atoms m - 3 , then the number of acceptor atoms in silicon per cubic centimetre will be
Options
- A2.5 × 10 30 atom c m - 3
- B2.5 × 10 35 atom c m - 3
- C1 × 10 13 atom c m - 3
- D1 × 10 15 atom c m - 3
Correct answer
D. 1 × 10 15 atom c m - 3
Step-by-step solution
Number density of atoms in silicon specimen = 5 × 10 28 atoms- m - 3 = 5 × 10 22 atoms c m - 3 . Since, 1 atom of indium is doped in 5 × 10 7 silicon atoms, so total number of indium atoms doped per c m 3 of silicon will be n = 5 × 10 22 5 × 10 7 = 10 15 atom- c m - 3 .