Answer: The temperature at which the intrinsic concentration exceeds the impurity density by factor of 10 is 636 K.
Explanation:
The given data is as follows.
[tex]N_{d} = 10^{19} per cm^{-3}[/tex]
[tex]N_{a} = 10^{15} per cm^{-3}[/tex]
As we are given that [tex]n_{i}[/tex]exceeds impurity density by a factor of 10.
Therefore, [tex]n_{i} = 10N_{d}[/tex]
[tex]10^{20} = 3.87 \times 10^{6} \times T^{\frac{3}{2}}e^({\frac{-7014}{T}})[/tex]
[tex]T^{\frac{3}{2}}e^({\frac{-7014}{T}}) = \frac{10^{20}}{3.87 \times 10^{6}}[/tex]
T = 1985 K
Also, [tex]n_{i} = 10N_{d}[/tex]
[tex]10^{6} = 3.87 \times 10^{16} \times T^{\frac{3}{2}}e^({\frac{-7014}{T}})[/tex]
T = 636 K
Thus, we can conclude that the temperature at which the intrinsic concentration exceeds the impurity density by factor of 10 is 636 K.
