Diffusion critical systems, temperature gradient

Diffusion in Critical Systems with a Temperature Gradient. 150... 

Diffusion systems are operated at near atmospheric or, in the hyper case, above atmospheric pressure. Precisely engineered dopant gradients at critical temperatures drive dopants into the lattice structure. Dopants are provided in much higher quantities in reactive atmospheres. Exhaust ventilation is required on both ends of the system to minimize exposures to the operators. The reactive and toxic constituents of the process gas streams must be removed before they can be safely vented away from the process. This usually involves the use of bum boxes and scmbbers to remove the toxic components and oxidatively consume any reactive species such as hydrogen or metal hydrides. 

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