Influence of Post-Annealing on Some Properties of Confocal Radio Frequency Sputtered ZnO Thin Film
Source abstract
Abstract
ZnO thin films were deposited on borosilicate glass substrates by confocal radio frequency (RF) magnetron sputtering and subsequently annealed in air at 300 °C and 500 °C for 60 min. The influence of thermal treatment on the structural, morphological, optical, and electrical properties was systematically investigated. X-ray diffraction (XRD) confirmed the formation of a hexagonal wurtzite phase with a pronounced (002) preferential orientation. Rietveld refinement analysis revealed that annealing led to a decrease in the lattice parameter c from 5.344 Å to 5.220 Å, an increase in crystallite size from 9.3 nm to 34.1 nm, and a reduction in microstrain from 0.0265 to 0.0027. Raman spectroscopy exhibited a sharper E 2 high mode at 438 cm -1 and a suppressed defect-related A₁(LO) mode (583 cm -1 ), evidencing enhanced crystallinity and defect passivation. Scanning electron microscopy (SEM) observations revealed grain coalescence and densification with increasing annealing temperature. The average optical transmittance improved from 70.8% to 82.2%, accompanied by a slight widening of the optical band gap from 3.22 eV to 3.27 eV. Hall measurements indicated a marked decrease in resistivity from 2.7 × 10 -2 Ω·cm to 5 × 10 -3 Ω·cm, yielding a maximum figure of merit of 1.68 × 10 -3 Ω -1 at 500 °C. Overall, post-deposition annealing is shown to significantly enhance crystallinity, reduce structural defects, and improve the optoelectronic performance of ZnO thin films, confirming their suitability for transparent electronics and photovoltaic applications.
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Research context
OpenAlex topics: ZnO doping and properties · Thin-Film Transistor Technologies · Chalcogenide Semiconductor Thin Films
SciVX discovery tags are terminology-based. OpenAlex topics are source-provided classifications.
Affiliations
Telecommunications Laboratory, Higher School of Signal, Kolea 42400
Badji Mokhtar-Annaba University
References (47)
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