Deposition parameters influencing structural and optical properties of SnO2/TiO2 thin films for UV photodetector environmental monitoring applications

Awad, Madeha; Rayan, Abdalrahman M.; Mohamed, Sodky Hamed

doi:10.21608/jsfw.2025.396793.1002

Deposition parameters influencing structural and optical properties of SnO2/TiO2 thin films for UV photodetector environmental monitoring applications

Document Type : Original Article

Authors

¹ Physics deparement, Faculty of science, Sohag University, 82524 Sohag, Egypt

² Physics Department, Faculty of Science, Sohag University

³ Faculty of Graduate Studies and Environmental Research, Sohag University, 82524 Sohag, Egypt

10.21608/jsfw.2025.396793.1002

Abstract

SnO2 thin films were synthesized on pre-sputtered TiO2 thin films using a thermal chemical vapor deposition technique under two deposition parameters: a high Oxygen flow rate (200 sccm; sample 1) and a longer deposition time (180 min ; sample 2). X-ray diffraction revealed high crystalline quality with three intermixing phases - SnO2, TiO2 and TiO26.72O48 for sample 2 in contrast to those synthesized at 200 sccm (sample 1). Morphological analysis supports the structural findings by revealing a uniform and denser microstruture in thin films prepared with moderate oxygen flow (75 sccm) but longer deposition time 180 min. Optical measurements showed moderate transparency under both conditions, with slightly lower transparency (60%), a higher refractive index (3.03) and a wider optical band gap (3.64 eV) in thin films of sample 2. The static dielectric constant obtained showed close proximity. these findings suggest the promise of using SnO2/TiO2 thin films in UV photodetectors applications.

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