Comment on - Direct experimental evidence for diffusion of dopants via pairs with intrinsic point defects.

In this response to a comment of K. Maser, the basic assumptions of pair diffusion theory and Maser's non- Fickian diffusion theory are reviewed in detail. It is concluded that both theories can be justified on the same basic mechanism with different assumptions on longranging interaction between vacancy and dopant. Experimental evidence was found to speak in favor of the pair diffusion theory