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First Brillouin zone of FCC lattice and the band diagram (Do you see any gaps?). Here is one with a gap !. This type of bandgap is called an “indirect bandgap” material. Band diagram of silicon. It is all about exciting electrons from the valence band.
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First Brillouin zone of FCC lattice and the band diagram (Do you see any gaps?)
Here is one with a gap ! This type of bandgap is called an “indirect bandgap” material. Band diagram of silicon
P-type semiconductor: Si doped with a 3 valence element that substitutes Si atoms in the lattice. Carriers are mainly holes N-type semiconductor: Si doped with a 5 valence element that substitutes Si atoms in the lattice. Carriers are electrons.
Facts: • Doping a semiconductor with a second element that has excess or fewer valence electrons than the number of bonds in pure Si changes the carrier amount and their types. • How “semiconduction” is manipulated has nothing to do with only single n-doped pr p-doped crystal. • When a p-doped crystal is brought into contact with an n-doped one, interesting things happen. • These “interesting things” determine how a transistor functions… • Every transistor is, this way or that way, a p-n junction.
Before any potential applied After potential applied