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Acceleration and deceleration of dopant diffusion in a semiconductor by space and time modulation of diffusion coefficient

✍ Scribed by Evgeny L. Pankratov

Publisher
Elsevier Science
Year
2004
Tongue
English
Weight
156 KB
Volume
114
Category
Article
ISSN
0167-7322

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✦ Synopsis

The integral relaxation time of dopant diffusion in a semiconductor has been analytically derived for the case of weakly space and time varying diffusion coefficient. It has been shown that the well-known integral criterion for the relaxation time is an optimal estimate of the relaxation time. The choosing of parameters of the diffusion coefficient for minimization and maximization of the relaxation time has been done. It has been demonstrated that in the case of heterostructure the most optimal structure, which accelerates the diffusion process, consists of three layers with some specific relation between diffusion coefficients of the layers. Is interesting to note, that the maximal deceleration of the diffusion process also occurs for the three layer structure, but with the opposite order of layers and different layer thickness, besides, maximal deceleration may be significantly larger than the maximal acceleration.

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