Deposition of ZnS thin films by electron beam evaporation technique, effect of thickness on the crystallographic and optical properties

Abstract

Deposition of Zinc sulfide (ZnS) thin films on Si (100) and glass substrates has been performed using electron beam evaporation (EBE) method without annealing. Film structure has been analyzed by XRD, while SEM and AFM have been used to explore the films morphology. Raman spectroscopy has been used to confirm film composition. The stoichiometry has been verified by EDX and XPS techniques. XRD patterns indicated that the films possess a polycrystalline cubic structure with orientations along (111) and (220) planes. The crystallinity has been better with film thickness in the 350–1700 nm range while the RMS roughness increases. Optical properties of the grown films were characterized by optical transmittance measurements (UV–Vis). The deduced energy band gap of the films shows a clear reduction from 3.45 eV to 3.36 eV with increasing film thickness. The evolution of refractive index, extinction coefficient, and dielectric constants with thickness has been investigated from transmittance spectra in the 500–1000 nm wavelength range.

Study of crystallographic, optical and sensing properties of Na2WO4 films deposited by thermal evaporation with several thickness

“…In the previous work, the gap and the quality revealed the same behavior for ZnO film [35] and for SnO 2 film [36]. These results are in contrast with the work by Rao et al [37] and Abdallah [38] where the energy gap was inversely proportional to the crystallite size.…”

HRTEM, XPS and XRD characterization of ZnS/PbS nanorods prepared by thermal evaporation technique

“…These results were in agreement with work of Benyahia et al [11], where thermal evaporation was also used for ZnS deposition and blende structure was obtained. The blende structure was also obtained in our previous work, where deposition was performed using electron gun techniques [16]. The identified PbS phase, galena, has also a cubic structure.…”

“…Hence, our product is a stoichiometric film. Films with same stoichiometry were also acquired by different techniques, such as ultrasonic spray pyrolysis [15] and electron beam evaporation [16]. For further investigation of the chemical composition of the product, XPS scan of the sample was performed (Fig.…”

“…Several methods have been used to prepare ZnS films by different research groups [11], such as magnetron sputtering [12,13], pulsed laser deposition, chemical bath deposition (CBD) [14], ultrasonic spray pyrolysis [15], electron gun evaporation [16] and thermal evaporation [12]. The latter is particularly interesting, due to its simplicity and cheapness.…”

Surface Morphology and Optical Properties of Cubic-Zinc Sulfide (C-Zns) Thin Films

“…Dislocation density (δ) and micro strain (ε) of the ZnS nano-grains were calculated using the following equations (2) and (3) (Gherouel et al, 2012; Sahay and Nath, 2008; Klug and Alexander, 1974). 1 (…”