Question

Indium antimonide has a band gap of 0.23 eV between the valence and the conduction band. Find the temperature at which kT equals the band gap.

Answer 1

Given:
Band gap between the conduction band and the valence band, E = 0.23 eV
Boltzmann's constant, k = 1.38 × 10⁻²³ J/K
We need to find the temperature at which thermal energy kT becomes equal to the band gap of indium antimonide.
∴ kT = E 

\[\Rightarrow 1 . 38 \times  {10}^{- 23}  \times T = 0 . 23 \times 1 . 6 \times  {10}^{- 19} \] 

\[ \Rightarrow T = \frac{0 . 23 \times 1 . 6 \times {10}^{- 19}}{1 . 38 \times {10}^{- 23}}\] 

\[ \Rightarrow T = \frac{0 . 23 \times 1 . 6 \times {10}^4}{1 . 38}\] 

\[ \Rightarrow T = 0 . 2666 \times  {10}^4  \approx 2670  \] K