A Study of a-Si:H Absorption Edge Using Dunstan’s Model

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Lana F. Sahal
https://orcid.org/0000-0002-2698-9596
Abdullah Al-Numan

Abstract

The optical absorption data of Hydrogenated Amorphous Silicon was analyzed using a Dunstan model of optical absorption in amorphous semiconductors. This model introduces disorder into the band-band absorption through a linear exponential distribution of local energy gaps, and it accounts for both the Urbach and Tauc regions of the optical absorption edge.Compared to other models of similar bases, such as the O’Leary and Guerra models, it is simpler to understand mathematically and has a physical meaning. The optical absorption data of Jackson et al and Maurer et al were successfully interpreted using Dunstan’s model. Useful physical parameters are extracted especially the band to the band energy gap , which is the energy gap in the absence of disorder, that can be interpreted as the mobility gap of the material.

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A Study of a-Si:H Absorption Edge Using Dunstan’s Model. Baghdad Sci.J [Internet]. 2023 Apr. 1 [cited 2024 Mar. 28];20(2):0466. Available from: https://bsj.uobaghdad.edu.iq/index.php/BSJ/article/view/6822
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How to Cite

1.
A Study of a-Si:H Absorption Edge Using Dunstan’s Model. Baghdad Sci.J [Internet]. 2023 Apr. 1 [cited 2024 Mar. 28];20(2):0466. Available from: https://bsj.uobaghdad.edu.iq/index.php/BSJ/article/view/6822

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