NEET2004PhysicsSemiconductorsActual
A Ge specimen is doped with Al . The concentration of acceptor atoms is 10²¹ atoms / m ^3 . Given that the intrinsic concentration of electron-hole pairs is 10¹⁹ / m ^3 , the concentration of electrons in the specimen is
Options
- A10¹⁷ / m ^3
- B10¹⁵ / m ^3
- C10^4 / m ^3
- D10^2 / m ^3 .
Correct answer
A. 10¹⁷ / m ^3
Step-by-step solution
When Ge specimen is doped with Al , then concentration of acceptor atoms is also called concentration of holes. Using formula, n_i^2=n₀ p₀ , where aligned n_i= & concentration of electron-hole pair =10¹⁹ / m ^3 & n₀= concentration of electron & p₀= concentration of holes =10²¹ atom / m ^3 & (10¹⁹ )^2=10²¹ n₀ n₀=10¹⁷ / m ^3 . aligned