The University of Southampton
University of Southampton Institutional Repository

Pulsed laser deposition of KNbO3 thin films

Pulsed laser deposition of KNbO3 thin films
Pulsed laser deposition of KNbO3 thin films
The laser ablation of stationary KNbO3 single crystal targets induces a Nb enrichment of the target surface. In rotated targets this effect is observed only in those areas irradiated with low laser fluence. The composition of the plasma formed close to the target surface is congruent with the target composition; however, at further distances K-deficient films are formed due to the preferential backscattering of K in the plasma. This loss may be compensated for by using K-rich ceramic targets. Best results so far have been obtained with [K]/[Nb] = 2.85 target composition, and crystalline KNbO3 films are formed when heating the substrates to 650 °C. Films formed on (100)MgO single crystals are usually single phase and oriented with the (110) film plane parallel to the (100) substrate surface. (100)NbO may coexist with KNbO3 on (100)MgO. At substrate temperatures higher than 650 °C, niobium diffuses into MgO forming Mg4Nb2O9 and NbO, leading to K evaporation from the film. Films formed on (001) alpha-Al2O3 (sapphire) show the coexistence of (111), (110), and (001) orientations of KNbO3, and the presence of NbO2 is also observed. KNbO3 films deposited on (001)LiNbO3 crystallize with the (111) plane of the film parallel to the substrate surface. For the latter two substrates the Nb diffusion into the substrate is lower than in MgO and consequently the K concentration retained in the film is comparatively larger.
2699-2706
Martin, M.J.
404681a1-831b-4a45-a232-d64690b7df70
Alfonso, J.E.
da7dab92-2998-4776-949c-4e717e8d3235
Mendiola, J.
0c3c5105-7d4c-414c-9857-78bc88310552
Zaldo, C.
fed559d7-64ba-4a7a-91d8-bb2ce13ee8e0
Gill, D.S.
0837886a-5999-478f-8b32-ea1996611c3c
Eason, R.W.
e38684c3-d18c-41b9-a4aa-def67283b020
Chandler, P.J.
df497652-94c6-4987-9fe1-a4b93111dadf
Martin, M.J.
404681a1-831b-4a45-a232-d64690b7df70
Alfonso, J.E.
da7dab92-2998-4776-949c-4e717e8d3235
Mendiola, J.
0c3c5105-7d4c-414c-9857-78bc88310552
Zaldo, C.
fed559d7-64ba-4a7a-91d8-bb2ce13ee8e0
Gill, D.S.
0837886a-5999-478f-8b32-ea1996611c3c
Eason, R.W.
e38684c3-d18c-41b9-a4aa-def67283b020
Chandler, P.J.
df497652-94c6-4987-9fe1-a4b93111dadf

Martin, M.J., Alfonso, J.E., Mendiola, J., Zaldo, C., Gill, D.S., Eason, R.W. and Chandler, P.J. (1997) Pulsed laser deposition of KNbO3 thin films. Journal of Materials Research, 12 (10), 2699-2706. (doi:10.1557/JMR.1997.0359).

Record type: Article

Abstract

The laser ablation of stationary KNbO3 single crystal targets induces a Nb enrichment of the target surface. In rotated targets this effect is observed only in those areas irradiated with low laser fluence. The composition of the plasma formed close to the target surface is congruent with the target composition; however, at further distances K-deficient films are formed due to the preferential backscattering of K in the plasma. This loss may be compensated for by using K-rich ceramic targets. Best results so far have been obtained with [K]/[Nb] = 2.85 target composition, and crystalline KNbO3 films are formed when heating the substrates to 650 °C. Films formed on (100)MgO single crystals are usually single phase and oriented with the (110) film plane parallel to the (100) substrate surface. (100)NbO may coexist with KNbO3 on (100)MgO. At substrate temperatures higher than 650 °C, niobium diffuses into MgO forming Mg4Nb2O9 and NbO, leading to K evaporation from the film. Films formed on (001) alpha-Al2O3 (sapphire) show the coexistence of (111), (110), and (001) orientations of KNbO3, and the presence of NbO2 is also observed. KNbO3 films deposited on (001)LiNbO3 crystallize with the (111) plane of the film parallel to the substrate surface. For the latter two substrates the Nb diffusion into the substrate is lower than in MgO and consequently the K concentration retained in the film is comparatively larger.

Text
1565.pdf - Version of Record
Restricted to Repository staff only
Request a copy

More information

Published date: October 1997

Identifiers

Local EPrints ID: 77920
URI: http://eprints.soton.ac.uk/id/eprint/77920
PURE UUID: c8727c96-582f-46a5-8376-f3b12063387d
ORCID for R.W. Eason: ORCID iD orcid.org/0000-0001-9704-2204

Catalogue record

Date deposited: 11 Mar 2010
Last modified: 14 Mar 2024 02:33

Export record

Altmetrics

Contributors

Author: M.J. Martin
Author: J.E. Alfonso
Author: J. Mendiola
Author: C. Zaldo
Author: D.S. Gill
Author: R.W. Eason ORCID iD
Author: P.J. Chandler

Download statistics

Downloads from ePrints over the past year. Other digital versions may also be available to download e.g. from the publisher's website.

View more statistics

Atom RSS 1.0 RSS 2.0

Contact ePrints Soton: eprints@soton.ac.uk

ePrints Soton supports OAI 2.0 with a base URL of http://eprints.soton.ac.uk/cgi/oai2

This repository has been built using EPrints software, developed at the University of Southampton, but available to everyone to use.

We use cookies to ensure that we give you the best experience on our website. If you continue without changing your settings, we will assume that you are happy to receive cookies on the University of Southampton website.

×