A p-type semiconductor has acceptor level 57 meV above valence band . The maximum wavelength of light required to create a hole is

Q: A p-type semiconductor has acceptor level 57 meV above valence band . The maximum wavelength of light required to create a hole is

(a) 11.61 × 10-33

(b) 57 × 10-3

(c) 217.1 × 103

(d) 57 A°

Ans: (c)

Sol: E = 57 × 10-3 × 1.6 × 10-19 J

$\large E = \frac{h c}{\lambda}$

$\large \lambda = \frac{h c}{E} = \frac{6.6 \times 10^{-34}\times 3 \times 10^8}{57 \times 10^{-3}\times 1.6 \times 10^{-19}}$

= 217.1 × 10-7 m

= 217.1 × 103