A Study of Energy Band Gap Temperature Relationships for Cu2ZnSnS4 Thin Films

TL;DR

This study investigates how the energy band gap of Cu2ZnSnS4 thin films varies with temperature, comparing empirical models to experimental data across a broad temperature range.

Contribution

It evaluates and compares empirical and semi-empirical models for temperature dependence of the band gap in Cu2ZnSnS4 thin films, identifying the most accurate models.

Findings

Varshni and P"assler models best fit mid-range temperatures.

Bose-Einstein model fits the entire temperature range well.

Calculated parameters align with Debye temperature estimates.

Abstract

The temperature dependent band gap energy of Cu2ZnSnS4 thin film was studied in the temperature range of 77 to 410 K. Various relevant parameters which explain the temperature variation of the fundamental band gap have been calculated using empirical and semi-empirical models. Amongst the models evaluated, the Varshni and P\"assler models show the best agreement with experimental data in the middle temperature range. However, the Bose-Einstein model fits reasonably well over the entire temperature range evaluated. The calculated fitting parameters are in good agreement with the estimated value of the Debye temperature calculated using the Madelung-Einstein approximation and the Hailing method.