Enhancing optoelectronic performance: Structural and optical properties of

Abstract

This work reports on the feasibility of using molybdenum-doped zinc oxide (MZO) thin films as transparent conductive electrode (TCE) material in optoelectronic applications, especially in solar cells. MZO films were deposited by RF magnetron sputtering in the thickness range of 100-500 nm and their electrical, optical, and structural properties were systematically studied. The results indicated that the electrical conductivity increased with the increase in film thickness, while the sheet resistance decreased; the 500 nm MZO film had the least resistance, which was about 362.4 Ω/sq. The optical measurements presented an average transmittance of about 77–84% in the visible range, with minor variations attributed to graphene integration in hybrid MZO+Graphene structures. The bandgap energy of MZO films decreased from 3.29 eV to 3.21 eV with increasing thickness, indicating the transition from quantum confinement toward bulk-like properties. SEM and EDXS analyses confirmed successful doping with molybdenum and gave insight into the surface morphology and chemical composition of the films. While MZO films with improved electrical and optical performances were reported when compared to undoped zinc oxide (ZnO), the hybrid structures showed a high sheet resistance due to inherent characteristics of graphene. The presented work demonstrates the MZO films as potential alternatives for more conventional TCE materials like indium tin oxide (ITO), considering their cost and availability issues, as well as their structure-related shortcomings.

Keywords

• MZO
• Magnetron sputtering
• Pressure
• Graphene

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