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The band gap for silicon is 1.1eV.(a)Fin...

The band gap for silicon is 1.1eV.(a)Find the ratio of the band gap to kT for silicon at room temperaature 300K.(b)At what tempareture does this ratio become one tenth of the value at 300K?(Silicon will not retain its structure at these high temperatures.)

Text Solution

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Given bandgap `= 1.1.eVT = 300K`
ratio` = 1.1/KT`
`= (1.1)/(8.62xx 10^(-5)xx3xx10^2)`
`= 42.53 =43`
(b)`4.253 = (1.1)/(8.62xx10^(-5)xxT)`
`T = (1.1xx10^5)/(4.253xx8.62)`
`= 3000.47K`
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