SAW gas sensor based on extremely thin strain-engineered K0.7Na0.3NbO3 films
| العنوان: | SAW gas sensor based on extremely thin strain-engineered K0.7Na0.3NbO3 films |
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| المؤلفون: | Dennis Finck, Jutta Schwarzkopf, Dirk Mayer, Marc W. Neis, Roger Wördenweber, Sijia Liang |
| المصدر: | Applied Physics Letters. 119:112905 |
| بيانات النشر: | AIP Publishing, 2021. |
| سنة النشر: | 2021 |
| مصطلحات موضوعية: | Materials science, Physics and Astronomy (miscellaneous), business.industry, Harmonics, Electrode, Optoelectronics, Acoustic wave, Substrate (electronics), business, Epitaxy, Signal, Piezoelectricity, Selective surface |
| الوصف: | In this work, we demonstrate that extremely thin strain-engineered K0.7Na0.3NbO3 (KNN) films are ideal candidates for highly sensitive and also potentially selective surface acoustic wave (SAW) sensor applications. The strength of the use of these films in SAW sensors is based on their piezoelectric properties and their thinness. The latter leads to a strong concentration of the SAW energy at the very surface of the sensor's delay line and the generation of higher harmonics with significant amplitudes. Thin epitaxial films of typically 30 nm in thickness are grown via liquid-delivery spin metal-organic vapor phase epitaxy on different (110)-oriented scandate substrates (TbScO3 and GdScO3). The epitaxial strain is induced by the lattice mismatch between a substrate and a film. The SAW signal of thin KNN films and the resulting sensitivity of an SAW thin KNN film sensor are compared with conventional bulk SAW sensors based on LiNbO3 (LN) using identical electrode designs for the generation and detection of the SAW for both systems. Compared to the conventional LN SAW sensor, our KNN-based sensor shows a sensitivity that is approximately 14 times higher. This was achieved using only the third and fifth harmonics. Using even higher harmonics, the improvement could potentially be boosted up to a factor > 40. Moreover, we showed that simultaneous sensor recording of mass loading at different harmonics is possible with the KNN sensor. Similar to other sensor concepts, the resulting multiple signals might provide a fingerprint of the detected material and, thus, lead to a selective detection of the mass load. |
| تدمد: | 1077-3118 0003-6951 |
| DOI: | 10.1063/5.0060796 |
| URL الوصول: | https://explore.openaire.eu/search/publication?articleId=doi_________::6d949bde27314e0f2bcd6593e31ac2e6 https://doi.org/10.1063/5.0060796 |
| رقم الانضمام: | edsair.doi...........6d949bde27314e0f2bcd6593e31ac2e6 |
| قاعدة البيانات: | OpenAIRE |
| تدمد: | 10773118 00036951 |
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| DOI: | 10.1063/5.0060796 |