Concept:Semiconductors have electrical resistivities intermediate between metallic conductors (\( \approx 10^{-8}\ \Omega\cdot\text{m} \)) and electrical insulators (\( \ge 10^{10}\ \Omega\cdot\text{m} \)).
Formula:$$\rho_{\text{conductor}} (10^{-8}\ \Omega\cdot\text{m}) < \rho_{\text{semiconductor}} (10^{-4}\text{ to } 10^4\ \Omega\cdot\text{m}) < \rho_{\text{insulator}} (10^{10}\text{ to } 10^{16}\ \Omega\cdot\text{m})$$
Solution:- Pure silicon has a resistivity of approximately \( 2.3 \times 10^3\ \Omega\cdot\text{m} \) at room temperature.
- Doping reduces this resistivity down to roughly \( 10^{-4}\ \Omega\cdot\text{m} \).
- Thus, standard semiconductors span the resistivity range of \( 10^{-4}\text{ to } 10^4\ \Omega\cdot\text{m} \).
Why other options are incorrect:- Option B: \( 10^{-8}\text{ to } 10^{-6}\ \Omega\cdot\text{m} \) is the resistivity range of metallic conductors (like copper and aluminium).
- Option C: \( 10^{12}\text{ to } 10^{18}\ \Omega\cdot\text{m} \) is the resistivity range of insulators (such as mica, glass, and quartz).
- Option D: Zero resistivity occurs only in superconductors below their critical transition temperature.
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