General Trends MX

The construction of diagrams over a range of concentrations and equilibrium constants allows a number of general conclusions to be drawn. 

1 Ke Ks In the undoped material a plateau is found over the middle part of the diagram where the dominant defects, [e ] and [h ], have equal concentrations. The point at which the solid is electronically neutral, when [e ] = [h ], occurs at the same partial pressure as when the solid is stoichiometric, [V J = [Vj J. 

In acceptor-doped material, the diagram is virtually unchanged for dopant levels below that of the intrinsic defects, that is, less than 1020 defects m-3 in the examples given above. When the concentration of acceptors passes this quantity, the [e ] = [h ] plateau lengthens and divides with [h ] greater than [e ]. The separation of these 

2 Ks Ke In the undoped material a plateau is found over the middle part of the diagram where the dominant defects, [V2/] and [V ], have equal 

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