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

150528 Suppose a ' \(n\) ' - type wafer is created by doping Si crystal having \(5 \times 10^{28}\) atoms \(/ \mathrm{m}^3\) with \(1 \mathrm{ppm}\) concentration of As. On the surface \(200 \mathrm{ppm}\) Boron is added to create ' \(P\) ' region in this wafer. Considering \(n_i=1.5 \times 10^{16} \mathrm{~m}^{-3}\) calculate the density of the minority charge carriers in the \(p\) regions.

1 \(2.25 \times 10^7 / \mathrm{m}^3\)
2 \(1.12 \times 10^3 / \mathrm{m}^3\)
3 \(3.11 \times 10^6 / \mathrm{m}^3\)
4 \(2.11 \times 10^5 / \mathrm{m}^3\)
Semiconductor Electronics Material Devices and Simple Circuits

150530 Mobility of electrons and holes in a sample of intrinsic \(\mathrm{Ge}\) at room temperature are \(0.35 \mathrm{~m}^2 / \mathrm{V}\)-s and \(0.18 \mathrm{~m}^2 / \mathrm{V}\)-s respectively. If the electron and hole densities are each equal to \(\mathbf{2 . 5} \times \mathbf{1 0} / \mathrm{m}^3\), the Ge conductivity will be

1 \(3.12 \mathrm{~S} / \mathrm{m}\)
2 \(2.12 \mathrm{~S} / \mathrm{m}\)
3 \(1.12 \mathrm{~S} / \mathrm{m}\)
4 \(4.12 \mathrm{~S} / \mathrm{m}\)
Semiconductor Electronics Material Devices and Simple Circuits

150532 A Ge specimen is doped with Al. The concentration of acceptor atoms is \(10^{21}\) atoms \(/ \mathrm{m}^3\). Given that the intrinsic concentration of electron-hole pairs is \(\sim 10^{19} / \mathrm{m}^3\), the concentration of electrons in the specimen is

1 \(10^{17} / \mathrm{m}^3\)
2 \(10^{15} / \mathrm{m}^3\)
3 \(10^4 / \mathrm{m}^3\)
4 \(10^2 / \mathrm{m}^3\)
Semiconductor Electronics Material Devices and Simple Circuits

150525 Assertion: The number of electrons in a p-type silicon semiconductor is less than the number of electrons in a pure silicon semiconductor at room temperature.
Reason: It is due to law of mass action.

1 If both Assertion and Reason are correct and the Reason is a correct explanation of the Assertion.
2 If both Assertion and Reason are correct but Reason in not a correct explanation of the Assertion.
3 If the Assertion is correct but Reason is incorrect.
4 If both the Assertion and Reason are incorrect.
5 If the Assertion is incorrect but the Reason is correct.
Semiconductor Electronics Material Devices and Simple Circuits

150528 Suppose a ' \(n\) ' - type wafer is created by doping Si crystal having \(5 \times 10^{28}\) atoms \(/ \mathrm{m}^3\) with \(1 \mathrm{ppm}\) concentration of As. On the surface \(200 \mathrm{ppm}\) Boron is added to create ' \(P\) ' region in this wafer. Considering \(n_i=1.5 \times 10^{16} \mathrm{~m}^{-3}\) calculate the density of the minority charge carriers in the \(p\) regions.

1 \(2.25 \times 10^7 / \mathrm{m}^3\)
2 \(1.12 \times 10^3 / \mathrm{m}^3\)
3 \(3.11 \times 10^6 / \mathrm{m}^3\)
4 \(2.11 \times 10^5 / \mathrm{m}^3\)
Semiconductor Electronics Material Devices and Simple Circuits

150530 Mobility of electrons and holes in a sample of intrinsic \(\mathrm{Ge}\) at room temperature are \(0.35 \mathrm{~m}^2 / \mathrm{V}\)-s and \(0.18 \mathrm{~m}^2 / \mathrm{V}\)-s respectively. If the electron and hole densities are each equal to \(\mathbf{2 . 5} \times \mathbf{1 0} / \mathrm{m}^3\), the Ge conductivity will be

1 \(3.12 \mathrm{~S} / \mathrm{m}\)
2 \(2.12 \mathrm{~S} / \mathrm{m}\)
3 \(1.12 \mathrm{~S} / \mathrm{m}\)
4 \(4.12 \mathrm{~S} / \mathrm{m}\)
Semiconductor Electronics Material Devices and Simple Circuits

150532 A Ge specimen is doped with Al. The concentration of acceptor atoms is \(10^{21}\) atoms \(/ \mathrm{m}^3\). Given that the intrinsic concentration of electron-hole pairs is \(\sim 10^{19} / \mathrm{m}^3\), the concentration of electrons in the specimen is

1 \(10^{17} / \mathrm{m}^3\)
2 \(10^{15} / \mathrm{m}^3\)
3 \(10^4 / \mathrm{m}^3\)
4 \(10^2 / \mathrm{m}^3\)
Semiconductor Electronics Material Devices and Simple Circuits

150525 Assertion: The number of electrons in a p-type silicon semiconductor is less than the number of electrons in a pure silicon semiconductor at room temperature.
Reason: It is due to law of mass action.

1 If both Assertion and Reason are correct and the Reason is a correct explanation of the Assertion.
2 If both Assertion and Reason are correct but Reason in not a correct explanation of the Assertion.
3 If the Assertion is correct but Reason is incorrect.
4 If both the Assertion and Reason are incorrect.
5 If the Assertion is incorrect but the Reason is correct.
Semiconductor Electronics Material Devices and Simple Circuits

150528 Suppose a ' \(n\) ' - type wafer is created by doping Si crystal having \(5 \times 10^{28}\) atoms \(/ \mathrm{m}^3\) with \(1 \mathrm{ppm}\) concentration of As. On the surface \(200 \mathrm{ppm}\) Boron is added to create ' \(P\) ' region in this wafer. Considering \(n_i=1.5 \times 10^{16} \mathrm{~m}^{-3}\) calculate the density of the minority charge carriers in the \(p\) regions.

1 \(2.25 \times 10^7 / \mathrm{m}^3\)
2 \(1.12 \times 10^3 / \mathrm{m}^3\)
3 \(3.11 \times 10^6 / \mathrm{m}^3\)
4 \(2.11 \times 10^5 / \mathrm{m}^3\)
Semiconductor Electronics Material Devices and Simple Circuits

150530 Mobility of electrons and holes in a sample of intrinsic \(\mathrm{Ge}\) at room temperature are \(0.35 \mathrm{~m}^2 / \mathrm{V}\)-s and \(0.18 \mathrm{~m}^2 / \mathrm{V}\)-s respectively. If the electron and hole densities are each equal to \(\mathbf{2 . 5} \times \mathbf{1 0} / \mathrm{m}^3\), the Ge conductivity will be

1 \(3.12 \mathrm{~S} / \mathrm{m}\)
2 \(2.12 \mathrm{~S} / \mathrm{m}\)
3 \(1.12 \mathrm{~S} / \mathrm{m}\)
4 \(4.12 \mathrm{~S} / \mathrm{m}\)
Semiconductor Electronics Material Devices and Simple Circuits

150532 A Ge specimen is doped with Al. The concentration of acceptor atoms is \(10^{21}\) atoms \(/ \mathrm{m}^3\). Given that the intrinsic concentration of electron-hole pairs is \(\sim 10^{19} / \mathrm{m}^3\), the concentration of electrons in the specimen is

1 \(10^{17} / \mathrm{m}^3\)
2 \(10^{15} / \mathrm{m}^3\)
3 \(10^4 / \mathrm{m}^3\)
4 \(10^2 / \mathrm{m}^3\)
Semiconductor Electronics Material Devices and Simple Circuits

150525 Assertion: The number of electrons in a p-type silicon semiconductor is less than the number of electrons in a pure silicon semiconductor at room temperature.
Reason: It is due to law of mass action.

1 If both Assertion and Reason are correct and the Reason is a correct explanation of the Assertion.
2 If both Assertion and Reason are correct but Reason in not a correct explanation of the Assertion.
3 If the Assertion is correct but Reason is incorrect.
4 If both the Assertion and Reason are incorrect.
5 If the Assertion is incorrect but the Reason is correct.
NEET Test Series from KOTA - 10 Papers In MS WORD WhatsApp Here
Semiconductor Electronics Material Devices and Simple Circuits

150528 Suppose a ' \(n\) ' - type wafer is created by doping Si crystal having \(5 \times 10^{28}\) atoms \(/ \mathrm{m}^3\) with \(1 \mathrm{ppm}\) concentration of As. On the surface \(200 \mathrm{ppm}\) Boron is added to create ' \(P\) ' region in this wafer. Considering \(n_i=1.5 \times 10^{16} \mathrm{~m}^{-3}\) calculate the density of the minority charge carriers in the \(p\) regions.

1 \(2.25 \times 10^7 / \mathrm{m}^3\)
2 \(1.12 \times 10^3 / \mathrm{m}^3\)
3 \(3.11 \times 10^6 / \mathrm{m}^3\)
4 \(2.11 \times 10^5 / \mathrm{m}^3\)
Semiconductor Electronics Material Devices and Simple Circuits

150530 Mobility of electrons and holes in a sample of intrinsic \(\mathrm{Ge}\) at room temperature are \(0.35 \mathrm{~m}^2 / \mathrm{V}\)-s and \(0.18 \mathrm{~m}^2 / \mathrm{V}\)-s respectively. If the electron and hole densities are each equal to \(\mathbf{2 . 5} \times \mathbf{1 0} / \mathrm{m}^3\), the Ge conductivity will be

1 \(3.12 \mathrm{~S} / \mathrm{m}\)
2 \(2.12 \mathrm{~S} / \mathrm{m}\)
3 \(1.12 \mathrm{~S} / \mathrm{m}\)
4 \(4.12 \mathrm{~S} / \mathrm{m}\)
Semiconductor Electronics Material Devices and Simple Circuits

150532 A Ge specimen is doped with Al. The concentration of acceptor atoms is \(10^{21}\) atoms \(/ \mathrm{m}^3\). Given that the intrinsic concentration of electron-hole pairs is \(\sim 10^{19} / \mathrm{m}^3\), the concentration of electrons in the specimen is

1 \(10^{17} / \mathrm{m}^3\)
2 \(10^{15} / \mathrm{m}^3\)
3 \(10^4 / \mathrm{m}^3\)
4 \(10^2 / \mathrm{m}^3\)
Semiconductor Electronics Material Devices and Simple Circuits

150525 Assertion: The number of electrons in a p-type silicon semiconductor is less than the number of electrons in a pure silicon semiconductor at room temperature.
Reason: It is due to law of mass action.

1 If both Assertion and Reason are correct and the Reason is a correct explanation of the Assertion.
2 If both Assertion and Reason are correct but Reason in not a correct explanation of the Assertion.
3 If the Assertion is correct but Reason is incorrect.
4 If both the Assertion and Reason are incorrect.
5 If the Assertion is incorrect but the Reason is correct.