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प्रश्न
Draw energy band diagrams of an n-type and p-type semiconductor at temperature T > 0 K. Mark the donor and acceptor energy levels with their energies.
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उत्तर
संबंधित प्रश्न
Distinguish between a metal and an insulator on the basis of energy band diagrams ?
When an electron goes from the valence band to the conduction band in silicon, its energy is increased by 1.1 eV. The average energy exchanged in a thermal collision is of the order of kT which is only 0.026 eV at room temperature. How is a thermal collision able to take some to the electrons from the valence band to the conduction band?
When a semiconducting material is doped with an impurity, new acceptor levels are created. In a particular thermal collision, a valence electron receives an energy equal to 2kT and just reaches one of the acceptor levels. Assuming that the energy of the electron was at the top edge of the valence band and that the temperature T is equal to 300 K, find the energy of the acceptor levels above the valence band.
Estimate the proportion of boron impurity which will increase the conductivity of a pure silicon sample by a factor of 100. Assume that each boron atom creates a hole and the concentration of holes in pure silicon at the same temperature is 7 × 1015 holes per cubic metre. Density of silicon 5 × 1028 atoms per cubic metre.
The product of the hole concentration and the conduction electron concentration turns out to be independent of the amount of any impurity doped. The concentration of conduction electrons in germanium is 6 × 1019 per cubic metref conduction electrons increases to 2 × 1023 per cubic metre. Find the concentration of the holes in the doped germanium.. When some phosphorus impurity is doped into a germanium sample, the concentration o
Hydrogen atom in n = 3 state has a lifetime of 10-10 sec. The number of revolutions an electron makes in the n = 3 state before returning to the ground state is ______.
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 common-base circuit calculate the change in the base current if that in the emitter current is αmA and a = 0.98
In a semiconductor, the forbidden energy gap between the valence, band and the conduction band is of the order of
Three photo diodes D1, D2 and D3 are made of semiconductors having band gaps of 2.5 eV, 2 eV and 3 eV, respectively. Which 0 ones will be able to detect light of wavelength 6000 Å?
The energy required by an electron to jump the forbidden band in silicon at room temperature is about ______.
