Energy gap measurements based on enhanced absorption coefficient calculation from transmittance and reflectance raw data

The absorption coefficient plays an important role in studying and characterizing semiconducting materials. It is an important parameter to study the mechanism of photons absorption within the structure of the studied material. Thus, it helps to study the several types of charge carrier transport along with the energy band structure and its defects. In literature, a formula was reported to precisely calculate the absorption coefficient from raw data of transmittance and reflectance of electromagnetic radiation. However, the reported formula has several issues limiting its validity in the literature. In this paper, we provide a more mathematically accurate form of this equation to precisely obtain the absorption coefficient from the raw data, by considering the total internal reflection at the different interfaces. Moreover, the equation is tested by simulated data and is applied to study the optical characteristics of a single-component epoxy resin from its transmittance and reflectance raw data.

Keywords

Absorption coefficients, Charge transition, Enhanced absorption, Gap measurements, Measurement-based, Photons absorption, Semiconducting materials, Tauc plots, Transmittance and reflectances, Urbach energy

Citation

PHYSICA SCRIPTA. 2024, vol. 99, issue 1, p. 1-9.
https://iopscience.iop.org/article/10.1088/1402-4896/ad1cb8

Document type

Peer-reviewed

Document version

Published version

Language of document

en

Document licence

Creative Commons Attribution 4.0 International
http://creativecommons.org/licenses/by/4.0/