Physics of Semiconductor Devices

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Silicon 100 surface

Silicon has the diamond crystal structure. The Bravais lattice is fcc and there are two atoms in the basis, one at 0,0,0 and one at 0.25, 0.25, 0.25. MOSFETs are usually made on 100 wafers. This is because the oxide that forms on 100 wafers is superior to the oxide that forms on other orientations. Draw the positions of the silicon atoms on the 100 surface. Draw the atoms at the surface as filled circles and the first layer of atoms beneath the surface as open circles. Label the 010 and 001 directions.