Open Access

ARTICLE

Investigation of Sputtered TiO₂ Thin Films and Modeling of TiO₂-Based Heterojunctions with p-Si and p-GaAs

Sana Handor^1,*, Mohamed Manoua², Mohamed Sahlaoui¹, Laura Hrostea³, Mustapha Adar⁴, Mohammed Sajieddine¹, Liviu Leontie³, Abdelati Razouk^1,*

1 Energy and Materials Engineering Laboratory (LGEM), Faculty of Science and Technology, Sultan Moulay Slimane University, Beni-Mellal, Morocco
2 Material Sciences Unit (USM), DERS, National Center for Energy, Sciences and Nuclear Techniques (CNESTEN), Rabat, Morocco
3 Research Center on Advanced Materials and Technologies (RAMTECH), Department of Exact and Natural Sciences, Institute of Interdisciplinary Research, Alexandru Ioan Cuza University of Iasi, 11 bd. Carol I, Iasi, Romania
4 Laboratory of Industrial Engineering and Surface Engineering, Faculty of Science and Technology, University Sultan Moulay Slimane, Beni Mellal, Morocco

* Corresponding Authors: Sana Handor. Email: ; Abdelati Razouk. Email:

(This article belongs to the Special Issue: Advances and Emerging Trends in Photovoltaic Technologies, Energy Storage, and Green Hydrogen)

Energy Engineering 2026, 123(9), 11 https://doi.org/10.32604/ee.2026.082739

Received 21 March 2026; Accepted 07 May 2026; Issue published 06 August 2026

Abstract

In this study, thin films of titanium dioxide (TiO₂) were deposited onto glass and indium tin oxide (ITO) substrates at room temperature, using plasma-assisted pulsed DC sputtering with a 99.9% pure stoichiometric TiO₂ target. Our research aims to investigate the influence of film thickness on the optical, structural, and morphological properties of TiO₂ nanostructured thin films, as well as its impact on the photovoltaic performance of heterojunctions where TiO₂ serves as the emitter. Using advanced PRISA software, parameters such as refractive index, film thickness, and band gap energy were determined. Spectrophotometry analysis shows that TiO₂ thin film samples exhibited up to 90% optical transparency in the UV-Vis spectral region. Using X-ray diffraction (XRD) analysis revealed an amorphous phase, particularly at lower scan angles, while atomic force microscopy (AFM) images show an homogeneous surface of deposited films with low roughness. A notable reduction in the optical band gap was observed with increasing film thickness. Finally, numerical simulations of TiO₂/p-Si and TiO₂/p-GaAs heterojunction Solar cells, performed using Atlas SILVACO software, predict promising photovoltaic performance based on the optical data of the elaborated TiO₂ thin films.

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