Effect of the Incorporation of Titanium on the Optical Properties of ZnO Thin Films: From Doping to Mixed Oxide Formation
ZnO films with Ti atoms incorporated (TZO) in a wide range (0–18 at.%) have been grown by reactive co-sputtering on silicon and glass substrates. The influence of the titanium incorporation in the ZnO matrix on the structural and optical characteristics of the samples has been determined b...
Main Authors: | , , , , , , |
---|---|
Format: | Article |
Language: | English |
Published: |
MDPI AG
2019-03-01
|
Series: | Coatings |
Subjects: | |
Online Access: | http://www.mdpi.com/2079-6412/9/3/180 |
id |
doaj-2bd7a5fef17d4e49a76ba7695f531e10 |
---|---|
record_format |
Article |
spelling |
doaj-2bd7a5fef17d4e49a76ba7695f531e102020-11-25T00:13:21ZengMDPI AGCoatings2079-64122019-03-019318010.3390/coatings9030180coatings9030180Effect of the Incorporation of Titanium on the Optical Properties of ZnO Thin Films: From Doping to Mixed Oxide FormationMiriam Yuste0Ramon Escobar-Galindo1Noelia Benito2Carlos Palacio3Oscar Martínez4Jose Maria Albella5Olga Sánchez6Instituto de Ciencia de Materiales de Madrid (CSIC), 28049 Madrid, SpainInstituto de Ciencia de Materiales de Madrid (CSIC), 28049 Madrid, SpainDept. de Física, Universidad de Concepción, Casilla 160-C, Concepción 4030000, ChileDept. de Física Aplicada, Universidad Autónoma de Madrid, 28049 Madrid, SpainUGdS-Optronlab Group, Dpto. Física Materia Condensada, Universidad de Valladolid, Paseo de Belén 11, 47011 Valladolid, SpainInstituto de Ciencia de Materiales de Madrid (CSIC), 28049 Madrid, SpainInstituto de Ciencia de Materiales de Madrid (CSIC), 28049 Madrid, SpainZnO films with Ti atoms incorporated (TZO) in a wide range (0–18 at.%) have been grown by reactive co-sputtering on silicon and glass substrates. The influence of the titanium incorporation in the ZnO matrix on the structural and optical characteristics of the samples has been determined by Rutherford backscattering spectroscopy (RBS), X-ray photoelectron spectroscopy (XPS) and X-ray diffraction (XRD). The results indicate that the samples with low Ti content (<4 at.%) exhibit a wurtzite-like structure, with the Ti4+ ions substitutionally incorporated into the ZnO structure, forming Ti-doped ZnO films. In particular, a very low concentration of Ti (<0.9 at.%) leads to a significant increase of the crystallinity of the TZO samples. Higher Ti contents give rise to a progressive amorphization of the wurtzite-like structure, so samples with high Ti content (≥18 at.%) display an amorphous structure, indicating in the XPS analysis, a predominance of Ti–O–Zn mixed oxides. The energy gap obtained from absorption spectrophotometry increases from 3.2 eV for pure ZnO films to 3.6 eV for those with the highest Ti content. Ti incorporation in the ZnO samples <0.9 at.% raises both the blue (380 nm) and green (approx. 550 nm) bands of the photoluminescence (PL) emission, thereby indicating a significant improvement of the PL efficiency of the samples.http://www.mdpi.com/2079-6412/9/3/180Ti doped ZnOthin filmco-sputteringUV-visible |
collection |
DOAJ |
language |
English |
format |
Article |
sources |
DOAJ |
author |
Miriam Yuste Ramon Escobar-Galindo Noelia Benito Carlos Palacio Oscar Martínez Jose Maria Albella Olga Sánchez |
spellingShingle |
Miriam Yuste Ramon Escobar-Galindo Noelia Benito Carlos Palacio Oscar Martínez Jose Maria Albella Olga Sánchez Effect of the Incorporation of Titanium on the Optical Properties of ZnO Thin Films: From Doping to Mixed Oxide Formation Coatings Ti doped ZnO thin film co-sputtering UV-visible |
author_facet |
Miriam Yuste Ramon Escobar-Galindo Noelia Benito Carlos Palacio Oscar Martínez Jose Maria Albella Olga Sánchez |
author_sort |
Miriam Yuste |
title |
Effect of the Incorporation of Titanium on the Optical Properties of ZnO Thin Films: From Doping to Mixed Oxide Formation |
title_short |
Effect of the Incorporation of Titanium on the Optical Properties of ZnO Thin Films: From Doping to Mixed Oxide Formation |
title_full |
Effect of the Incorporation of Titanium on the Optical Properties of ZnO Thin Films: From Doping to Mixed Oxide Formation |
title_fullStr |
Effect of the Incorporation of Titanium on the Optical Properties of ZnO Thin Films: From Doping to Mixed Oxide Formation |
title_full_unstemmed |
Effect of the Incorporation of Titanium on the Optical Properties of ZnO Thin Films: From Doping to Mixed Oxide Formation |
title_sort |
effect of the incorporation of titanium on the optical properties of zno thin films: from doping to mixed oxide formation |
publisher |
MDPI AG |
series |
Coatings |
issn |
2079-6412 |
publishDate |
2019-03-01 |
description |
ZnO films with Ti atoms incorporated (TZO) in a wide range (0–18 at.%) have been grown by reactive co-sputtering on silicon and glass substrates. The influence of the titanium incorporation in the ZnO matrix on the structural and optical characteristics of the samples has been determined by Rutherford backscattering spectroscopy (RBS), X-ray photoelectron spectroscopy (XPS) and X-ray diffraction (XRD). The results indicate that the samples with low Ti content (<4 at.%) exhibit a wurtzite-like structure, with the Ti4+ ions substitutionally incorporated into the ZnO structure, forming Ti-doped ZnO films. In particular, a very low concentration of Ti (<0.9 at.%) leads to a significant increase of the crystallinity of the TZO samples. Higher Ti contents give rise to a progressive amorphization of the wurtzite-like structure, so samples with high Ti content (≥18 at.%) display an amorphous structure, indicating in the XPS analysis, a predominance of Ti–O–Zn mixed oxides. The energy gap obtained from absorption spectrophotometry increases from 3.2 eV for pure ZnO films to 3.6 eV for those with the highest Ti content. Ti incorporation in the ZnO samples <0.9 at.% raises both the blue (380 nm) and green (approx. 550 nm) bands of the photoluminescence (PL) emission, thereby indicating a significant improvement of the PL efficiency of the samples. |
topic |
Ti doped ZnO thin film co-sputtering UV-visible |
url |
http://www.mdpi.com/2079-6412/9/3/180 |
work_keys_str_mv |
AT miriamyuste effectoftheincorporationoftitaniumontheopticalpropertiesofznothinfilmsfromdopingtomixedoxideformation AT ramonescobargalindo effectoftheincorporationoftitaniumontheopticalpropertiesofznothinfilmsfromdopingtomixedoxideformation AT noeliabenito effectoftheincorporationoftitaniumontheopticalpropertiesofznothinfilmsfromdopingtomixedoxideformation AT carlospalacio effectoftheincorporationoftitaniumontheopticalpropertiesofznothinfilmsfromdopingtomixedoxideformation AT oscarmartinez effectoftheincorporationoftitaniumontheopticalpropertiesofznothinfilmsfromdopingtomixedoxideformation AT josemariaalbella effectoftheincorporationoftitaniumontheopticalpropertiesofznothinfilmsfromdopingtomixedoxideformation AT olgasanchez effectoftheincorporationoftitaniumontheopticalpropertiesofznothinfilmsfromdopingtomixedoxideformation |
_version_ |
1725394827091116032 |