Segregation Ratios of Impurities in Silicon

The values in the table show why B would be better than A1 for intentionally doping bulk Si grown by the Czochralski method. First, one would need 400 times more A1 in the melt than B to achieve the same bulk doping level in the boule. Second, as the melt is used up in forming the solid the number of A1 atoms in liquid is relatively unchanged while the Si is consumed. Thus the A1 concentration in both the liquid and solid rises increasingly rapidly as the crystal grows. By contrast, because B is removed from the liquid at nearly the same rate as Si, the concentration in the melt and hence in the sohd remains nearly constant. 

will be established. A changing concentration of impurity in the liquid with 

Planes and directions in these lattices are indexed with three-integers in cubic systems. 

Each lattice point on the Bravais lattice may have more than one atom associated with it. 

A primitive cell also may be defined containing exactly one formula unit of atoms of the compound. 

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