High-temperature stable piezoelectric transducers using epitaxially grown electrodes

<p>Piezoelectric resonators are of great importance for application in high-precision transducers. However, at elevated temperatures, the degradation of commonly used metal electrodes may affect the performance of oxide electrodes of piezoelectric transducers; with sufficiently high electrical...

Full description

Bibliographic Details
Main Authors: H. Wulfmeier, R. Feder, L. Zhao, H. Fritze
Format: Article
Language:English
Published: Copernicus Publications 2020-01-01
Series:Journal of Sensors and Sensor Systems
Online Access:https://www.j-sens-sens-syst.net/9/15/2020/jsss-9-15-2020.pdf
_version_ 1819177167448178688
author H. Wulfmeier
R. Feder
L. Zhao
H. Fritze
author_facet H. Wulfmeier
R. Feder
L. Zhao
H. Fritze
author_sort H. Wulfmeier
collection DOAJ
description <p>Piezoelectric resonators are of great importance for application in high-precision transducers. However, at elevated temperatures, the degradation of commonly used metal electrodes may affect the performance of oxide electrodes of piezoelectric transducers; with sufficiently high electrical conductivity they are expected to overcome this deficit. In the latter case, the stable operation of piezoelectric transducers could be further enhanced if the resonator and electrodes would consist of identical or at least very similar materials; thus, nearly monolithic resonators are created.</p> <p>The present work focuses on two major aspects: the growth of high-quality langasite (<span class="inline-formula">La<sub>3</sub>Ga<sub>5</sub>SiO<sub>14</sub></span>; LGS) and doped LGS thin-film electrode layers by pulsed laser ablation and the characterization of the developed resonator devices. To obtain epitaxial films of the correct stoichiometry, the deposition on heated substrates is performed in oxygen atmosphere in the range from 10<span class="inline-formula"><sup>−3</sup></span> to 10&thinsp;Pa. Another requirement for adjusting the stoichiometry is an increased Ga content in the sputter targets with respect to LGS to account for Ga evaporation during film deposition. Additional doping with Sr increases the electrode film conductivity; thus combined with the use of low-conductivity single-crystalline catangasite (<span class="inline-formula">Ca<sub>3</sub>TaGa<sub>3</sub>Si<sub>2</sub>O<sub>14</sub></span>; CTGS) substrates the ratio between the electrical conductivities of the substrate and the film is increased, enabling the preparation of nearly monolithic resonators. The properties of these nearly monolithic resonators are characterized in the temperature range of 600 to 1000&thinsp;<span class="inline-formula"><sup>∘</sup></span>C and compared to those of CTGS resonator blanks without electrodes. Particular attention is paid to the reproducibility of resonator properties, the electrode orientation and the quality factor. The created nearly monolithic resonator demonstrates stable operation in the temperature range from 600 to 1000&thinsp;<span class="inline-formula"><sup>∘</sup></span>C.</p>
first_indexed 2024-12-22T21:22:21Z
format Article
id doaj.art-c4768ce84ad745038883ae98649ce4c3
institution Directory Open Access Journal
issn 2194-8771
2194-878X
language English
last_indexed 2024-12-22T21:22:21Z
publishDate 2020-01-01
publisher Copernicus Publications
record_format Article
series Journal of Sensors and Sensor Systems
spelling doaj.art-c4768ce84ad745038883ae98649ce4c32022-12-21T18:12:10ZengCopernicus PublicationsJournal of Sensors and Sensor Systems2194-87712194-878X2020-01-019152610.5194/jsss-9-15-2020High-temperature stable piezoelectric transducers using epitaxially grown electrodesH. WulfmeierR. FederL. ZhaoH. Fritze<p>Piezoelectric resonators are of great importance for application in high-precision transducers. However, at elevated temperatures, the degradation of commonly used metal electrodes may affect the performance of oxide electrodes of piezoelectric transducers; with sufficiently high electrical conductivity they are expected to overcome this deficit. In the latter case, the stable operation of piezoelectric transducers could be further enhanced if the resonator and electrodes would consist of identical or at least very similar materials; thus, nearly monolithic resonators are created.</p> <p>The present work focuses on two major aspects: the growth of high-quality langasite (<span class="inline-formula">La<sub>3</sub>Ga<sub>5</sub>SiO<sub>14</sub></span>; LGS) and doped LGS thin-film electrode layers by pulsed laser ablation and the characterization of the developed resonator devices. To obtain epitaxial films of the correct stoichiometry, the deposition on heated substrates is performed in oxygen atmosphere in the range from 10<span class="inline-formula"><sup>−3</sup></span> to 10&thinsp;Pa. Another requirement for adjusting the stoichiometry is an increased Ga content in the sputter targets with respect to LGS to account for Ga evaporation during film deposition. Additional doping with Sr increases the electrode film conductivity; thus combined with the use of low-conductivity single-crystalline catangasite (<span class="inline-formula">Ca<sub>3</sub>TaGa<sub>3</sub>Si<sub>2</sub>O<sub>14</sub></span>; CTGS) substrates the ratio between the electrical conductivities of the substrate and the film is increased, enabling the preparation of nearly monolithic resonators. The properties of these nearly monolithic resonators are characterized in the temperature range of 600 to 1000&thinsp;<span class="inline-formula"><sup>∘</sup></span>C and compared to those of CTGS resonator blanks without electrodes. Particular attention is paid to the reproducibility of resonator properties, the electrode orientation and the quality factor. The created nearly monolithic resonator demonstrates stable operation in the temperature range from 600 to 1000&thinsp;<span class="inline-formula"><sup>∘</sup></span>C.</p>https://www.j-sens-sens-syst.net/9/15/2020/jsss-9-15-2020.pdf
spellingShingle H. Wulfmeier
R. Feder
L. Zhao
H. Fritze
High-temperature stable piezoelectric transducers using epitaxially grown electrodes
Journal of Sensors and Sensor Systems
title High-temperature stable piezoelectric transducers using epitaxially grown electrodes
title_full High-temperature stable piezoelectric transducers using epitaxially grown electrodes
title_fullStr High-temperature stable piezoelectric transducers using epitaxially grown electrodes
title_full_unstemmed High-temperature stable piezoelectric transducers using epitaxially grown electrodes
title_short High-temperature stable piezoelectric transducers using epitaxially grown electrodes
title_sort high temperature stable piezoelectric transducers using epitaxially grown electrodes
url https://www.j-sens-sens-syst.net/9/15/2020/jsss-9-15-2020.pdf
work_keys_str_mv AT hwulfmeier hightemperaturestablepiezoelectrictransducersusingepitaxiallygrownelectrodes
AT rfeder hightemperaturestablepiezoelectrictransducersusingepitaxiallygrownelectrodes
AT lzhao hightemperaturestablepiezoelectrictransducersusingepitaxiallygrownelectrodes
AT hfritze hightemperaturestablepiezoelectrictransducersusingepitaxiallygrownelectrodes