Semiconductors and Electronic Devices
Pure silicon at room temperature has an electron number density in the conduction band of about $$5 \times 10^{15}m^{-3}$$ and an equal density of holes in the valence band. Suppose that one of every $$10^7$$ silicon atoms is replaced by a phosphorus atom. $$(a)$$ Which type will the
doped semiconductor be, $$n$$ or $$p?$$ $$(b)$$ What charge carrier number density will the phosphorus add? $$(c)$$ What is the ratio of the charge carrier number density (electrons in the conduction band and holes
in the valence band) in the doped silicon to that in pure silicon?
Semiconductors and Electronic Devices
When a photon enters the depletion zone of a $$p-n$$ junction, the photon can scatter from the valence electrons there, transferring part of its energy to each electron, which then jumps to the conduction band. Thus, the photon creates electron–hole pairs. For this reason, the junctions are often used as light detectors, especially in the x-ray and gamma-ray regions of the electromagnetic spectrum. Suppose a single $$662$$ $$keV$$ gamma-ray photon transfers its energy to electrons in multiple scattering events inside a semiconductor with an energy gap of $$1.1 eV$$, until all the energy is transferred. Assuming that each electron jumps the gap from the top of the valence band to the bottom of the conduction band, find the number of electron-hole pairs created by the process.
Semiconductors and Electronic Devices
Which statement is correct
Semiconductors and Electronic Devices
Number of secondary electrons emitted per number of primary electrons depends on
Semiconductors and Electronic Devices
If $$n_{e}$$ and $$n_{h}$$ are the number of electrons and holes in a semiconductor heavily doped with phosphorus, then
Semiconductors and Electronic Devices
The difference in the variation of resistance with temperature in a metal and a semiconductor arises essentially due to the difference in the
Semiconductors and Electronic Devices
If $$n_e$$ and $$v_d$$ be the number of electrons and drift velocity in a semiconductor. When the temperature is increased
Semiconductors and Electronic Devices
When a forward is applied to a p-n junction, then what happens to the potential barrier $$V_{B}$$ and the width of charge depleted region x
Semiconductors and Electronic Devices
The length of germanium rod is 0.928 cm and its area of cross-section is 1 $$mm^{ 2 }$$. If for germanium $${ n }_{ 1 }=2.5\times { 10 }^{ 19 }{ m }^{ -3 },\mu _{ h }=0.19m^{ 2 }V^{ -1 }s^{ -1 },\mu _{ e }=0.39m^{ 2 }V^{ -1 }s^{ -1 }$$
Semiconductors and Electronic Devices
Pure Si at 300 K has equal electron $$\left( {{n_e}} \right)$$ and hole $$\left( {{n_h}} \right)$$ concentration of $$1.5 \times {10^{ + 16}}{{\text{m}}^{ - 3}}$$.Doping by the indium, $$\left( {{n_h}} \right)$$increasess to $$3 \times {10^{ 22}}{{\text{m}}^{ - 3}}$$. What is $$\left( {{n_e}} \right)$$ in doped Si ?
