Estimation of electron diffusion length and life-time in nano-porous semi-conductors with a two-scale random walk method

Ebrahimi, Fatemeh; Moghaddas, Mahla; Koochi, Hakimeh

doi:10.22055/jrmbs.2017.12999

Estimation of electron diffusion length and life-time in nano-porous semi-conductors with a two-scale random walk method

Document Type : Full length research Paper

Authors

¹ University of Birjand

² Birjand Universirty

10.22055/jrmbs.2017.12999

Abstract

In this study, we modified the two-scale method proposed by Ebrahimi and Koochi to simulate electron diffusion in a disordered nano-structured semiconductor and study the effect of recombination process in localized traps, on electron transport. In the first scale, we estimate the mean electron residence time for nano particles with an arbitrary coordination number. In the second scale, we estimate the electron lifetime when it travels through a disordered percolating cluster of nano particles. The electron residence time on each particle was evaluated in the first scale. Some of the nano particles have recombination centers. We find that while employing the two-scale method decreases the computational time drastically, it produces the correct dependence of diffusion coefficients on the material’s porosity.

Keywords

References

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