Jean Baptiste Perrin Nobel Prize in physics 1926
![](https://slidetodoc.com/presentation_image/86d8067f01eb0230748b1dc6ef0b15e2/image-1.jpg)
![Jean Baptiste Perrin Nobel Prize in physics 1926 He demonstrated that the current in Jean Baptiste Perrin Nobel Prize in physics 1926 He demonstrated that the current in](http://slidetodoc.com/presentation_image/86d8067f01eb0230748b1dc6ef0b15e2/image-2.jpg)
Jean Baptiste Perrin Nobel Prize in physics 1926 He demonstrated that the current in a vacuum tube was due to electron motion.
![Collisions of particles affects the mobility term. - + Effective mass! Collisions of particles affects the mobility term. - + Effective mass!](http://slidetodoc.com/presentation_image/86d8067f01eb0230748b1dc6ef0b15e2/image-3.jpg)
Collisions of particles affects the mobility term. - + Effective mass!
![Lattice structure will also vibrate due to T > 0 “lattice scattering” Lattice structure will also vibrate due to T > 0 “lattice scattering”](http://slidetodoc.com/presentation_image/86d8067f01eb0230748b1dc6ef0b15e2/image-4.jpg)
Lattice structure will also vibrate due to T > 0 “lattice scattering”
![Electron & ion density and conductivity versus temperature -- silicon Electron & ion density and conductivity versus temperature -- silicon](http://slidetodoc.com/presentation_image/86d8067f01eb0230748b1dc6ef0b15e2/image-5.jpg)
Electron & ion density and conductivity versus temperature -- silicon
![Typical mobility values Silicon 1350 480 Gallium arsenide 8500 400 Germanium 3900 1900 Typical mobility values Silicon 1350 480 Gallium arsenide 8500 400 Germanium 3900 1900](http://slidetodoc.com/presentation_image/86d8067f01eb0230748b1dc6ef0b15e2/image-6.jpg)
Typical mobility values Silicon 1350 480 Gallium arsenide 8500 400 Germanium 3900 1900
![Conductivity densities may be different Conductivity densities may be different](http://slidetodoc.com/presentation_image/86d8067f01eb0230748b1dc6ef0b15e2/image-7.jpg)
Conductivity densities may be different
![Restrictions in design Restrictions in design](http://slidetodoc.com/presentation_image/86d8067f01eb0230748b1dc6ef0b15e2/image-8.jpg)
Restrictions in design
![resistivity Exercise 4. 3 For a particular silicon semiconductor device at room temperature, the resistivity Exercise 4. 3 For a particular silicon semiconductor device at room temperature, the](http://slidetodoc.com/presentation_image/86d8067f01eb0230748b1dc6ef0b15e2/image-9.jpg)
resistivity Exercise 4. 3 For a particular silicon semiconductor device at room temperature, the required material is to be n type with a resistivity of = 0. 1 -cm. (a) determine the required impurity doping concentration and (b) the resulting electron mobility. Impurity concentration
![Semiconductors are nonlinear. Velocity depends on electric field. Semiconductors are nonlinear. Velocity depends on electric field.](http://slidetodoc.com/presentation_image/86d8067f01eb0230748b1dc6ef0b15e2/image-10.jpg)
Semiconductors are nonlinear. Velocity depends on electric field.
![](http://slidetodoc.com/presentation_image/86d8067f01eb0230748b1dc6ef0b15e2/image-11.jpg)
![Semiconductors are nonlinear. Ga. As Velocity depends on electric field. Semiconductors are nonlinear. Ga. As Velocity depends on electric field.](http://slidetodoc.com/presentation_image/86d8067f01eb0230748b1dc6ef0b15e2/image-12.jpg)
Semiconductors are nonlinear. Ga. As Velocity depends on electric field.
![Diffusion current is due to density gradient of density Diffusion current is due to density gradient of density](http://slidetodoc.com/presentation_image/86d8067f01eb0230748b1dc6ef0b15e2/image-13.jpg)
Diffusion current is due to density gradient of density
![Diffusion current is due to density gradient of density Diffusion current is due to density gradient of density](http://slidetodoc.com/presentation_image/86d8067f01eb0230748b1dc6ef0b15e2/image-14.jpg)
Diffusion current is due to density gradient of density
![Exercise 4. 5 Assume that, in an n-type Ga. As semiconductor at T = Exercise 4. 5 Assume that, in an n-type Ga. As semiconductor at T =](http://slidetodoc.com/presentation_image/86d8067f01eb0230748b1dc6ef0b15e2/image-15.jpg)
Exercise 4. 5 Assume that, in an n-type Ga. As semiconductor at T = 300°K the electron concentration varies linearly. Calculate the magnitude of the diffusion current density.
![Typical values Silicon 1350 35 480 12. 4 Gallium arsenide 8500 200 400 10. Typical values Silicon 1350 35 480 12. 4 Gallium arsenide 8500 200 400 10.](http://slidetodoc.com/presentation_image/86d8067f01eb0230748b1dc6ef0b15e2/image-16.jpg)
Typical values Silicon 1350 35 480 12. 4 Gallium arsenide 8500 200 400 10. 4 Germanium 3900 101 1900 49. 2
![Diffusion current is due to density gradient of density – nonuniform doping Diffusion current is due to density gradient of density – nonuniform doping](http://slidetodoc.com/presentation_image/86d8067f01eb0230748b1dc6ef0b15e2/image-17.jpg)
Diffusion current is due to density gradient of density – nonuniform doping
![Diffusion of electrons - Diffusion of electrons -](http://slidetodoc.com/presentation_image/86d8067f01eb0230748b1dc6ef0b15e2/image-18.jpg)
Diffusion of electrons -
![Diffusion of electrons Diffusion of electrons](http://slidetodoc.com/presentation_image/86d8067f01eb0230748b1dc6ef0b15e2/image-19.jpg)
Diffusion of electrons
![Diffusion of electrons Diffusion of electrons](http://slidetodoc.com/presentation_image/86d8067f01eb0230748b1dc6ef0b15e2/image-20.jpg)
Diffusion of electrons
![Exercise 4. 6 Assume that the donor impurity concentration In a semiconductor is given Exercise 4. 6 Assume that the donor impurity concentration In a semiconductor is given](http://slidetodoc.com/presentation_image/86d8067f01eb0230748b1dc6ef0b15e2/image-21.jpg)
Exercise 4. 6 Assume that the donor impurity concentration In a semiconductor is given by Determine the electric field induced in the material in this impurity concentration.
![Total current density– 4 components Total current density– 4 components](http://slidetodoc.com/presentation_image/86d8067f01eb0230748b1dc6ef0b15e2/image-22.jpg)
Total current density– 4 components
![The electron density changes differently than the ion density The electron density changes differently than the ion density](http://slidetodoc.com/presentation_image/86d8067f01eb0230748b1dc6ef0b15e2/image-23.jpg)
The electron density changes differently than the ion density
![Einstein relations Einstein relations](http://slidetodoc.com/presentation_image/86d8067f01eb0230748b1dc6ef0b15e2/image-24.jpg)
Einstein relations
![Einstein relations Einstein relations](http://slidetodoc.com/presentation_image/86d8067f01eb0230748b1dc6ef0b15e2/image-25.jpg)
Einstein relations
![Due to T > 0, “lattice scattering” This effects mobility & diffusion! Due to T > 0, “lattice scattering” This effects mobility & diffusion!](http://slidetodoc.com/presentation_image/86d8067f01eb0230748b1dc6ef0b15e2/image-26.jpg)
Due to T > 0, “lattice scattering” This effects mobility & diffusion!
![National Public Radio puzzle combinations of 2 & 7 & j yields 8 National Public Radio puzzle combinations of 2 & 7 & j yields 8](http://slidetodoc.com/presentation_image/86d8067f01eb0230748b1dc6ef0b15e2/image-27.jpg)
National Public Radio puzzle combinations of 2 & 7 & j yields 8
![](http://slidetodoc.com/presentation_image/86d8067f01eb0230748b1dc6ef0b15e2/image-28.jpg)
![Golf course for the elderly Golf course for the elderly](http://slidetodoc.com/presentation_image/86d8067f01eb0230748b1dc6ef0b15e2/image-29.jpg)
Golf course for the elderly
![](http://slidetodoc.com/presentation_image/86d8067f01eb0230748b1dc6ef0b15e2/image-30.jpg)
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