Structural Investigation of ZnO Thin Films Obtained by Annealing after Thermal Evaporation

Year 2019, Volume: 23 Issue: 4, 650 - 656, 01.08.2019

Gökhan Utlu

https://doi.org/10.16984/saufenbilder.450190

Cited By: 2

Abstract

In this
study, ZnO thin films, with thicknesses of 80-240 nm are prepared by thermal
evaporation of ZnO pellets on glass substrates. Then, these films are annealed
in air atmosphere at 300°C for 2
hours. ZnO formation has been investigated as a function of the film thickness.
As deposited films appear to be brown since they are rich in Zn, whereas Zn
phases are replaced by ZnO phases after annealing and the films show a
transparent appearance. In thinner films (80-100 nm) the ZnO phases are not
observed but Zn phase intensities decrease. Especially when the thickness is
increased in 132-240 nm thick films, ZnO phases are observed after annealing, and
their intensity is increased and polycrystalline structures are formed. XRD
measurements show that Zn (002), Zn (100) and Zn (101) phases are present in
our films before annealing. After annealing, the intensity of these zinc peaks
decreases firstly due to the film thickness, and then at ZnO (100), ZnO (002)
and ZnO (101) phases are formed. SEM, AFM analyzes show that ZnOs are formed in
the form of nanorods on the surface and after these anneal the columnar growths
occur and the particle diameters increase.

 

Keywords

ZnO thin film, thermal evaporation, annealing, XRD, SEM

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