Energy Bands (Valance, Conduction, Energy Gap), Conductor Insulator and Semiconductor
Semiconductor Electronics Material Devices and Simple Circuits

150628 What is the maximum wavelength of photon that would excite an electron in the valence band of diamond to the conduction band? The energy gap for diamond is \(5.5 \mathrm{eV}\).

1 \(169 \mathrm{~nm}\)
2 \(205 \mathrm{~nm}\)
3 \(226 \mathrm{~nm}\)
4 \(350 \mathrm{~nm}\)
Semiconductor Electronics Material Devices and Simple Circuits

150632 You are given four semiconductors \(P, Q, R\) and \(S\) with respective band gaps \(4 \mathrm{eV}, 3 \mathrm{eV}, 2 \mathrm{eV}\) and \(1 \mathrm{eV}\) for use in a photodetector to detect \(\lambda=1400 \mathrm{~nm}\). Select the suitable semiconductor.

1 \(\mathrm{P}\)
2 \(\mathrm{Q}\)
3 \(\mathrm{R}\)
4 \(\mathrm{S}\)
Semiconductor Electronics Material Devices and Simple Circuits

150638 An intrinsic semiconductor has a resistivity of \(0.50 \Omega\) at room temperature. Find the intrinsic carrier concentration if the mobilities of electrons and holes are \(0.39 \mathrm{~m}^2 /\) volt sec and \(0.11 \mathrm{~m}^2 /\) volt sec respectively

1 \(1.2 \times 10^{18} / \mathrm{m}^3\)
2 \(2.5 \times 10^{19} / \mathrm{m}^3\)
3 \(1.9 \times 10^{20} / \mathrm{m}^3\)
4 \(3.1 \times 10^{21} / \mathrm{m}^3\)
Semiconductor Electronics Material Devices and Simple Circuits

150662 Suppose a pure \(\mathrm{Si}\) crystal has \(5 \times 10^{\mathbf{2 8}}\) atoms \(\mathrm{m}^{-3}\). It is doped by 1 ppm concentration of pentavalent As. Calculate the number of electron and holes. Given that \(\mathbf{n}_{\mathrm{i}}=1.5 \times 10^{16}\) \(\mathbf{m}^{-3}\)

1 \(6.5 \times 10^9 \mathrm{~m}^{-3}\)
2 \(4.5 \times 10^9 \mathrm{~m}^{-3}\)
3 \(5.5 \times 10^9 \mathrm{~m}^{-3}\)
4 \(5.5 \times 10^9 \mathrm{~m}^{-3}\)
Semiconductor Electronics Material Devices and Simple Circuits

150628 What is the maximum wavelength of photon that would excite an electron in the valence band of diamond to the conduction band? The energy gap for diamond is \(5.5 \mathrm{eV}\).

1 \(169 \mathrm{~nm}\)
2 \(205 \mathrm{~nm}\)
3 \(226 \mathrm{~nm}\)
4 \(350 \mathrm{~nm}\)
Semiconductor Electronics Material Devices and Simple Circuits

150632 You are given four semiconductors \(P, Q, R\) and \(S\) with respective band gaps \(4 \mathrm{eV}, 3 \mathrm{eV}, 2 \mathrm{eV}\) and \(1 \mathrm{eV}\) for use in a photodetector to detect \(\lambda=1400 \mathrm{~nm}\). Select the suitable semiconductor.

1 \(\mathrm{P}\)
2 \(\mathrm{Q}\)
3 \(\mathrm{R}\)
4 \(\mathrm{S}\)
Semiconductor Electronics Material Devices and Simple Circuits

150638 An intrinsic semiconductor has a resistivity of \(0.50 \Omega\) at room temperature. Find the intrinsic carrier concentration if the mobilities of electrons and holes are \(0.39 \mathrm{~m}^2 /\) volt sec and \(0.11 \mathrm{~m}^2 /\) volt sec respectively

1 \(1.2 \times 10^{18} / \mathrm{m}^3\)
2 \(2.5 \times 10^{19} / \mathrm{m}^3\)
3 \(1.9 \times 10^{20} / \mathrm{m}^3\)
4 \(3.1 \times 10^{21} / \mathrm{m}^3\)
Semiconductor Electronics Material Devices and Simple Circuits

150662 Suppose a pure \(\mathrm{Si}\) crystal has \(5 \times 10^{\mathbf{2 8}}\) atoms \(\mathrm{m}^{-3}\). It is doped by 1 ppm concentration of pentavalent As. Calculate the number of electron and holes. Given that \(\mathbf{n}_{\mathrm{i}}=1.5 \times 10^{16}\) \(\mathbf{m}^{-3}\)

1 \(6.5 \times 10^9 \mathrm{~m}^{-3}\)
2 \(4.5 \times 10^9 \mathrm{~m}^{-3}\)
3 \(5.5 \times 10^9 \mathrm{~m}^{-3}\)
4 \(5.5 \times 10^9 \mathrm{~m}^{-3}\)
Semiconductor Electronics Material Devices and Simple Circuits

150628 What is the maximum wavelength of photon that would excite an electron in the valence band of diamond to the conduction band? The energy gap for diamond is \(5.5 \mathrm{eV}\).

1 \(169 \mathrm{~nm}\)
2 \(205 \mathrm{~nm}\)
3 \(226 \mathrm{~nm}\)
4 \(350 \mathrm{~nm}\)
Semiconductor Electronics Material Devices and Simple Circuits

150632 You are given four semiconductors \(P, Q, R\) and \(S\) with respective band gaps \(4 \mathrm{eV}, 3 \mathrm{eV}, 2 \mathrm{eV}\) and \(1 \mathrm{eV}\) for use in a photodetector to detect \(\lambda=1400 \mathrm{~nm}\). Select the suitable semiconductor.

1 \(\mathrm{P}\)
2 \(\mathrm{Q}\)
3 \(\mathrm{R}\)
4 \(\mathrm{S}\)
Semiconductor Electronics Material Devices and Simple Circuits

150638 An intrinsic semiconductor has a resistivity of \(0.50 \Omega\) at room temperature. Find the intrinsic carrier concentration if the mobilities of electrons and holes are \(0.39 \mathrm{~m}^2 /\) volt sec and \(0.11 \mathrm{~m}^2 /\) volt sec respectively

1 \(1.2 \times 10^{18} / \mathrm{m}^3\)
2 \(2.5 \times 10^{19} / \mathrm{m}^3\)
3 \(1.9 \times 10^{20} / \mathrm{m}^3\)
4 \(3.1 \times 10^{21} / \mathrm{m}^3\)
Semiconductor Electronics Material Devices and Simple Circuits

150662 Suppose a pure \(\mathrm{Si}\) crystal has \(5 \times 10^{\mathbf{2 8}}\) atoms \(\mathrm{m}^{-3}\). It is doped by 1 ppm concentration of pentavalent As. Calculate the number of electron and holes. Given that \(\mathbf{n}_{\mathrm{i}}=1.5 \times 10^{16}\) \(\mathbf{m}^{-3}\)

1 \(6.5 \times 10^9 \mathrm{~m}^{-3}\)
2 \(4.5 \times 10^9 \mathrm{~m}^{-3}\)
3 \(5.5 \times 10^9 \mathrm{~m}^{-3}\)
4 \(5.5 \times 10^9 \mathrm{~m}^{-3}\)
Semiconductor Electronics Material Devices and Simple Circuits

150628 What is the maximum wavelength of photon that would excite an electron in the valence band of diamond to the conduction band? The energy gap for diamond is \(5.5 \mathrm{eV}\).

1 \(169 \mathrm{~nm}\)
2 \(205 \mathrm{~nm}\)
3 \(226 \mathrm{~nm}\)
4 \(350 \mathrm{~nm}\)
Semiconductor Electronics Material Devices and Simple Circuits

150632 You are given four semiconductors \(P, Q, R\) and \(S\) with respective band gaps \(4 \mathrm{eV}, 3 \mathrm{eV}, 2 \mathrm{eV}\) and \(1 \mathrm{eV}\) for use in a photodetector to detect \(\lambda=1400 \mathrm{~nm}\). Select the suitable semiconductor.

1 \(\mathrm{P}\)
2 \(\mathrm{Q}\)
3 \(\mathrm{R}\)
4 \(\mathrm{S}\)
Semiconductor Electronics Material Devices and Simple Circuits

150638 An intrinsic semiconductor has a resistivity of \(0.50 \Omega\) at room temperature. Find the intrinsic carrier concentration if the mobilities of electrons and holes are \(0.39 \mathrm{~m}^2 /\) volt sec and \(0.11 \mathrm{~m}^2 /\) volt sec respectively

1 \(1.2 \times 10^{18} / \mathrm{m}^3\)
2 \(2.5 \times 10^{19} / \mathrm{m}^3\)
3 \(1.9 \times 10^{20} / \mathrm{m}^3\)
4 \(3.1 \times 10^{21} / \mathrm{m}^3\)
Semiconductor Electronics Material Devices and Simple Circuits

150662 Suppose a pure \(\mathrm{Si}\) crystal has \(5 \times 10^{\mathbf{2 8}}\) atoms \(\mathrm{m}^{-3}\). It is doped by 1 ppm concentration of pentavalent As. Calculate the number of electron and holes. Given that \(\mathbf{n}_{\mathrm{i}}=1.5 \times 10^{16}\) \(\mathbf{m}^{-3}\)

1 \(6.5 \times 10^9 \mathrm{~m}^{-3}\)
2 \(4.5 \times 10^9 \mathrm{~m}^{-3}\)
3 \(5.5 \times 10^9 \mathrm{~m}^{-3}\)
4 \(5.5 \times 10^9 \mathrm{~m}^{-3}\)