TS EAMCET · Physics · Semiconductors
The number of silicon atoms per \(\mathrm{m}^3\) is \(5 \times 10^{28}\). This is doped with \(4.5 \times 10^{21}\) atoms \(/ \mathrm{m}^3\) of Arsenic. The ratio of number of electrons to number of holes after doping is (Take \(n_i=\) Number of thermally-generated electrons \(\left.=1.5 \times 10^{16} / \mathrm{m}^3\right)\)
- A \(4.5 \times 10^{12}\)
- B \(8 \times 10^{14}\)
- C \(9 \times 10^{12}\)
- D \(9 \times 10^{11}\)
Answer & Solution
Correct Answer
(C) \(9 \times 10^{12}\)
Step-by-step Solution
Detailed explanation
We have \[ \mathrm{n}_{\mathrm{e}}=4.5 \times 10^{21} \] As \(\mathrm{n}_{\mathrm{h}}=\frac{\mathrm{n}_{\mathrm{i}}^2}{\mathrm{n}_{\mathrm{e}}}=\frac{\left(1.5 \times 10^{16}\right)^2}{4.5 \times 10^{21}}\) \[ \Rightarrow \mathrm{n}_{\mathrm{h}}-5 \times 10^{10} \] So,…
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