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Question
The energy required by an electron to jump the forbidden band in silicon at room temperature is about ______.
Options
0.01 eV
0.05 eV
0.7 eV
1.1 eV
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Solution
The energy required by an electron to jump the forbidden band in silicon at room temperature is about 1.1 eV.
Explanation:
For pure Si, the band gap or forbidden gap is 1.1 eV. An electron must therefore have this much energy to jump the forbidden band in Si at room temperature.
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Useful data
`1/(4pi∈_0) = 8.99 xx 10^-34`N m2 C-2; e = 1.60 10-19 C; h = 6.63 10-34 Js; me = 9 × 10-3 kg
In a semiconductor, the forbidden energy gap between the valence, band and the conduction band is of the order of
