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Ionization energy Extrinsic semiconductors

Ionization energy Extrinsic semiconductors. Ionization energy – Bohr model. +. -. Ionization energy – Bohr model. Happy Hearts Day!. Happy Hearts Day!. Donor energy. Ionization energy – Bohr model. Ionization energy << bandgap energy. Fermi-Dirac distribution. Fermi energy.

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Ionization energy Extrinsic semiconductors

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  1. Ionization energy Extrinsic semiconductors

  2. Ionization energy – Bohr model + -

  3. Ionization energy – Bohr model

  4. Happy Hearts Day! Happy Hearts Day! Donor energy Ionization energy – Bohr model Ionization energy << bandgap energy

  5. Fermi-Dirac distribution

  6. Fermi energy Distribution of states & electronsFermi function T = 0° T > 0° . .

  7. Figure 3-1 a

  8. Figure 3-1 a

  9. Problem 3.5 The magnitude of the product g(E) & Fermi(E) in the conduction band is a function of energy as shown in Figure 3.1. Assume the Boltzmann approximation is valid. Determine the energy with respect to Ec at which the maximum occurs.

  10. Problem 3.5

  11. Problem 3.5

  12. Typical numbers Normalized electron effective mass Normalized hole effective mass Silicon 1.08 0.56 Gallium arsenide 0.067 0.48 Germanium 0.55 0.37 Normalized mass equals effective mass/rest mass of the electron

  13. n type extrinsic semiconductor Thermal correction

  14. p type extrinsic semiconductor Thermal correction

  15. Ionization energies in silicon and germanium in electron volts Impurity Si Ge Donors Phosphorus 0.045 0.012 Arsenic 0.05 0.0127 Acceptors Boron 0.045 0.0104 Aluminum 0.06 0.0102

  16. Electron motion in the conduction band Currents

  17. A current can exist If there are Free electrons In the conduction band! Conduction band Valence band

  18. E Current density – charges in motion - +

  19. E collisions +

  20. E collisions +

  21. E collisions +

  22. Lattice structure will also vibrate due to T > 0“lattice scattering”

  23. Conductivity and resistivity Conductivity Resistivity

  24. V L A Conductivity and resistivity I

  25. You enter the laboratory and see an experiment. How will you know which class is it? If it's green and wiggles, it's biology. If it stinks, it's chemistry. If it doesn't work, it's physics.

  26. Teachers' remarks that changed the history of physics Copernicus, when will you understand that you are not the center of the world?Galileo, if you will drop stones from the top of the tower one more time, you will be dismissed forever.Kepler, till when will you stare at the sky?Newton, will you please stop idling away under the apple tree?Ohm, must you resist Ampere's opinions on current events?Nikola Tesla, I see that everyone is attracted to your magnetic personality.Einstein, a crocodile is greener or is it wider? Schrödinger, stop abusing cats!Heisenberg, when will you be sure of yourself?

  27. Simple three-dimensional unit cell

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