Study of the Influence of Annealing Temperature on the Structural and Optical Properties of ZnTe Prepared by Vacuum Thermal Evaporation Technique

Sarmad M Ali,Alia A.A Shehab,Samir A Maki

doi:10.30526/31.1.1851

Sarmad M Ali, Alia A.A Shehab + Show 1 more

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https://doi.org/10.30526/31.1.1851

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Abstract

The ZnTe alloy was prepared as deposited thin films on the glass substrates at a thickness of 400Â±20 nm using vacuum evaporation technique at pressure (1 Ã— 10-5) mbar and room temperature. Then the thin films under vacuum (2 Ã— 10-3 mbar) were annealing at (RT,100 and 300) Â°C for one hour. The structural properties were studied by using X-ray diffraction and AFM, the results show that the thin films had approached the single crystalline in the direction (111) as preferred orientation of the structure zinc-blende for cubic type, with small peaks of tellurium (Te) element for all prepared thin films. The calculated crystallite size (Cs) decreased with the increase in the annealing temperature, from (25) nm before the annealing to (21) nm after the annealing. The images of atomic force microscopy of all thin films appeared a homogenous structure and high smoothness through roughness values â€‹â€‹that increased slightly from (1.4) nm to (3.4) nm. The optical properties of the ZnTe at (RT,100 and 300) Â°C were studied transmittance and absorbance spectrum as a function of the wavelength. The energy gap was found about (2.4) eV for the thin films before the annealing and increased slightly to (2.5) eV after annealing at 300 Â°C

Highlights

Zinc Telluride (ZnTe) is one of the most important semiconductor materials was used in many applications in the electronics device field
Zinc telluride can be classed to the II–VI group of semiconductor compounds and like other family of the group, the material has a direct band gap of 2.26eV at RT [2,3], which corresponds to the pure green region of the electromagnetic spectra, and it is seen as a potential material for the fabrication of green LEDs
ZnTe thin films can be fabricated by using closed space sublimation (CSS) technique [6], sputtering [7], electro-deposition process[8], electron beam evaporation[9] and thermal vacuum evaporation method[10].In the present paper an attempt has been made to study the effect of annealing temperature on the structural and optical properties ZnTe thin films prepared by vacuum

Summary

Introduction

Zinc Telluride (ZnTe) is one of the most important semiconductor materials was used in many applications in the electronics device field. Considering that all of them reflect X-rays in the same direction, so the particle size increases with increasing intensity and decreasing the value of FWHM .The distance between the crystalline planar (dhkl) which corresponds to the results of the standard information card, is calculated using the Bragg equation [11].

Results

Conclusion