Electrical and Structural Properties of Semi-Polar-ZnO/<i>a</i>-Al<sub>2</sub>O<sub>3</sub> and Polar-ZnO/<i>c</i>-Al<sub>2</sub>O<sub>3</sub> Films: A Comparative Study

In this work, the properties of ZnO films of 100 nm thickness, grown using atomic layer deposition (ALD) on <i>a</i>–(100) and <i>c</i>–(001) oriented Al<sub>2</sub>O<sub>3</sub> substrate are reported. The films were grown in the same growth condition...

Full description

Bibliographic Details
Main Authors: Sushma Mishra, Wojciech Paszkowicz, Adrian Sulich, Rafal Jakiela, Monika Ożga, Elżbieta Guziewicz
Format: Article
Language:English
Published: MDPI AG 2022-12-01
Series:Materials
Subjects:
Online Access:https://www.mdpi.com/1996-1944/16/1/151
_version_ 1797625404626829312
author Sushma Mishra
Wojciech Paszkowicz
Adrian Sulich
Rafal Jakiela
Monika Ożga
Elżbieta Guziewicz
author_facet Sushma Mishra
Wojciech Paszkowicz
Adrian Sulich
Rafal Jakiela
Monika Ożga
Elżbieta Guziewicz
author_sort Sushma Mishra
collection DOAJ
description In this work, the properties of ZnO films of 100 nm thickness, grown using atomic layer deposition (ALD) on <i>a</i>–(100) and <i>c</i>–(001) oriented Al<sub>2</sub>O<sub>3</sub> substrate are reported. The films were grown in the same growth conditions and parameters at six different growth temperatures (T<sub>g</sub>) ranging from 100 °C to 300 °C. All as-grown and annealed films were found to be polycrystalline, highly (001) oriented for the <i>c</i>–Al<sub>2</sub>O<sub>3</sub> and highly (101) oriented for the <i>a</i>–Al<sub>2</sub>O<sub>3</sub> substrate. The manifestation of semi-polar-(101) and polar (001)–oriented ZnO films on the same substrate provided the opportunity for a comparative study in terms of the influence of polarization on the electrical and structural properties of ZnO films. It was found that the concentration of hydrogen, carbon, and nitrogen impurities in polar (001)–oriented films was considerably higher than in semi-polar (101)–oriented ZnO films. The study showed that when transparent conductive oxide applications were considered, the ZnO layers could be deposited at a temperature of about 160 °C, because, at this growth temperature, the high electrical conductivity was accompanied by surface smoothness in the nanometer scale. On the contrary, semi-polar (101)–oriented films might offer a perspective for obtaining p-type ZnO films, because the concentration of carbon and hydrogen impurities is considerably lower than in polar films.
first_indexed 2024-03-11T09:56:05Z
format Article
id doaj.art-85858cd090914e0281b683cb0c803beb
institution Directory Open Access Journal
issn 1996-1944
language English
last_indexed 2024-03-11T09:56:05Z
publishDate 2022-12-01
publisher MDPI AG
record_format Article
series Materials
spelling doaj.art-85858cd090914e0281b683cb0c803beb2023-11-16T15:47:43ZengMDPI AGMaterials1996-19442022-12-0116115110.3390/ma16010151Electrical and Structural Properties of Semi-Polar-ZnO/<i>a</i>-Al<sub>2</sub>O<sub>3</sub> and Polar-ZnO/<i>c</i>-Al<sub>2</sub>O<sub>3</sub> Films: A Comparative StudySushma Mishra0Wojciech Paszkowicz1Adrian Sulich2Rafal Jakiela3Monika Ożga4Elżbieta Guziewicz5Institute of Physics, Polish Academy of Sciences, Al. Lotników 32/46, 02-668 Warsaw, PolandInstitute of Physics, Polish Academy of Sciences, Al. Lotników 32/46, 02-668 Warsaw, PolandInstitute of Physics, Polish Academy of Sciences, Al. Lotników 32/46, 02-668 Warsaw, PolandInstitute of Physics, Polish Academy of Sciences, Al. Lotników 32/46, 02-668 Warsaw, PolandInstitute of Physics, Polish Academy of Sciences, Al. Lotników 32/46, 02-668 Warsaw, PolandInstitute of Physics, Polish Academy of Sciences, Al. Lotników 32/46, 02-668 Warsaw, PolandIn this work, the properties of ZnO films of 100 nm thickness, grown using atomic layer deposition (ALD) on <i>a</i>–(100) and <i>c</i>–(001) oriented Al<sub>2</sub>O<sub>3</sub> substrate are reported. The films were grown in the same growth conditions and parameters at six different growth temperatures (T<sub>g</sub>) ranging from 100 °C to 300 °C. All as-grown and annealed films were found to be polycrystalline, highly (001) oriented for the <i>c</i>–Al<sub>2</sub>O<sub>3</sub> and highly (101) oriented for the <i>a</i>–Al<sub>2</sub>O<sub>3</sub> substrate. The manifestation of semi-polar-(101) and polar (001)–oriented ZnO films on the same substrate provided the opportunity for a comparative study in terms of the influence of polarization on the electrical and structural properties of ZnO films. It was found that the concentration of hydrogen, carbon, and nitrogen impurities in polar (001)–oriented films was considerably higher than in semi-polar (101)–oriented ZnO films. The study showed that when transparent conductive oxide applications were considered, the ZnO layers could be deposited at a temperature of about 160 °C, because, at this growth temperature, the high electrical conductivity was accompanied by surface smoothness in the nanometer scale. On the contrary, semi-polar (101)–oriented films might offer a perspective for obtaining p-type ZnO films, because the concentration of carbon and hydrogen impurities is considerably lower than in polar films.https://www.mdpi.com/1996-1944/16/1/151ZnOstrainmicrostraindislocation densitymorphologySIMS
spellingShingle Sushma Mishra
Wojciech Paszkowicz
Adrian Sulich
Rafal Jakiela
Monika Ożga
Elżbieta Guziewicz
Electrical and Structural Properties of Semi-Polar-ZnO/<i>a</i>-Al<sub>2</sub>O<sub>3</sub> and Polar-ZnO/<i>c</i>-Al<sub>2</sub>O<sub>3</sub> Films: A Comparative Study
Materials
ZnO
strain
microstrain
dislocation density
morphology
SIMS
title Electrical and Structural Properties of Semi-Polar-ZnO/<i>a</i>-Al<sub>2</sub>O<sub>3</sub> and Polar-ZnO/<i>c</i>-Al<sub>2</sub>O<sub>3</sub> Films: A Comparative Study
title_full Electrical and Structural Properties of Semi-Polar-ZnO/<i>a</i>-Al<sub>2</sub>O<sub>3</sub> and Polar-ZnO/<i>c</i>-Al<sub>2</sub>O<sub>3</sub> Films: A Comparative Study
title_fullStr Electrical and Structural Properties of Semi-Polar-ZnO/<i>a</i>-Al<sub>2</sub>O<sub>3</sub> and Polar-ZnO/<i>c</i>-Al<sub>2</sub>O<sub>3</sub> Films: A Comparative Study
title_full_unstemmed Electrical and Structural Properties of Semi-Polar-ZnO/<i>a</i>-Al<sub>2</sub>O<sub>3</sub> and Polar-ZnO/<i>c</i>-Al<sub>2</sub>O<sub>3</sub> Films: A Comparative Study
title_short Electrical and Structural Properties of Semi-Polar-ZnO/<i>a</i>-Al<sub>2</sub>O<sub>3</sub> and Polar-ZnO/<i>c</i>-Al<sub>2</sub>O<sub>3</sub> Films: A Comparative Study
title_sort electrical and structural properties of semi polar zno i a i al sub 2 sub o sub 3 sub and polar zno i c i al sub 2 sub o sub 3 sub films a comparative study
topic ZnO
strain
microstrain
dislocation density
morphology
SIMS
url https://www.mdpi.com/1996-1944/16/1/151
work_keys_str_mv AT sushmamishra electricalandstructuralpropertiesofsemipolarznoiaialsub2subosub3subandpolarznoicialsub2subosub3subfilmsacomparativestudy
AT wojciechpaszkowicz electricalandstructuralpropertiesofsemipolarznoiaialsub2subosub3subandpolarznoicialsub2subosub3subfilmsacomparativestudy
AT adriansulich electricalandstructuralpropertiesofsemipolarznoiaialsub2subosub3subandpolarznoicialsub2subosub3subfilmsacomparativestudy
AT rafaljakiela electricalandstructuralpropertiesofsemipolarznoiaialsub2subosub3subandpolarznoicialsub2subosub3subfilmsacomparativestudy
AT monikaozga electricalandstructuralpropertiesofsemipolarznoiaialsub2subosub3subandpolarznoicialsub2subosub3subfilmsacomparativestudy
AT elzbietaguziewicz electricalandstructuralpropertiesofsemipolarznoiaialsub2subosub3subandpolarznoicialsub2subosub3subfilmsacomparativestudy