Piezoelectric Thin Films and their Applications

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Piezoelectric Thin Films and their Applications

M. Rizwan, A. Ayub, I. Ilyas, F. Seeart, T. Noor

Lead free piezoelectric thin films are very pivotal in technological applications. There has been a tremendous amount of research in the lead free piezoelectric thin films. KNN and ZnO piezoelectric thin films are very crucial in the miniaturization of piezoelectric devices. Characterization methods for piezoelectric thin films such as resonant spectrum method and pneumatic loading method are briefly deliberated here. Piezoelectric thin films provide several advantages in various applications such as highly sensitive sensors, large displacements and low voltage actuators. All applications of piezoelectric materials exhibit a high piezoelectric coefficient, insight into future outlook and integration for real-world applications is deliberated here.

Keywords
Thin Films, ZnO, Actuators, Sensors, Piezoelectric Properties, BAW Sensors

Published online 2022/09/01, 36 pages

Citation: M. Rizwan, A. Ayub, I. Ilyas, F. Seeart, T. Noor, Piezoelectric Thin Films and their Applications, Materials Research Foundations, Vol. 131, pp 186-221, 2022

DOI: https://doi.org/10.21741/9781644902097-7

Part of the book on Advanced Functional Piezoelectric Materials and Applications

References
[1] A.M. Abyzov, Aluminium oxide and alumina ceramics (review). Part 2. Foreign manufacturers. Technologies and research in the field of alumina ceramics,Refract. Ind. Ceram. 2 (2019) 13-22. https://doi.org/10.17073/1683-4518-2019-2-13-22
[2] M.A. Ahmad, R. Planas, Piezoelectric coefficients of thin film aluminum nitride characterizations using capacitance measurements. IEEE Microw. Wirel. Compon. Lett. 19(3). (2009) 140-142. https://doi.org/10.1109/LMWC.2009.2013682
[3] A.S. Bhalla, R. Guo, The perovskite structure-a review of its role in ceramic science and technology. Materials research innovations, Mater. Res. Innov. 4(1) (2000) 3-26. https://doi.org/10.1007/s100190000062
[4] P.K. Bhujbal , H.M. Pathan, Temperature dependent studies on radio frequency sputtered al doped zno thin film, Eng. 10( 2020) 58-67. https://doi.org/10.30919/es8d1003
[5] J.Böhlmark, Fundamentals of high power impulse magnetron sputtering, kemi och biologi,Institutionen för fysik, (2006)
[6] M.A. Caro, S. Zhang, T. Riekkinen, M. Ylilammi, M.A. , Lopez-Acevedo, O., Molarius,J. T. Laurila, Piezoelectric coefficients and spontaneous polarization of scaln, J. Condens. Matter Phys. 27(24) (2015) p. 245901. https://doi.org/10.1088/0953-8984/27/24/245901
[7] Chelliah, C.R. John, R. Swaminathan, Pulsed laser deposited hexagonal wurzite zno thin-film nanostructures/nanotextures for nanophotonics applications, J. 12(1) (2018) p. 016013. https://doi.org/10.1117/1.JNP.12.016013
[8] Z. Chen, Y. Wu, Y. Yang, J. Li, , B. Xie, , X. Li, S. Lei, J. Ou-Yang, X. Yang, Q. Zhou, Multilayered carbon nanotube yarn based optoacoustic transducer with high energy conversion efficiency for ultrasound application, Nano Energy. 46 (2018) p. 314-321. https://doi.org/10.1016/j.nanoen.2018.02.006
[9] N. Chidambaram, A. Mazzalai,P. Muralt, Measurement of effective piezoelectric coefficients of pzt thin films for energy harvesting application with interdigitated electrodes, IEEE Trans. Ultrason. Ferroelectr. Freq. Controll. 59(8) (2012) p. 1624-1631. https://doi.org/10.1109/TUFFC.2012.2368
[10] C.R. Cho, C-axis oriented (na, k) nbo3 thin films on si substrates using metalorganic chemical vapor deposition, Mater. Lett. 57(4) (2002) p. 781-786. https://doi.org/10.1016/S0167-577X(02)00872-8
[11] D. D’Agostino, C. Di Giorgio,A. Di Trolio, A. Guarino,A.M. Cucolo, A. Vecchione,F. Bobba, Piezoelectricity and charge trapping in zno and co-doped zno thin films, AIP. Adv. 7(5) (2017) p. 055010. https://doi.org/10.1063/1.4983474
[12] Directive, 96/ec of the european parliament and of the council of 27 january 2003 on waste electrical and electronic equipment (weee), Official Journal of the European Union , 37 (2002) p. 24-38.
[13] R.E. Eitel, C.A. Randall, T.R. Shrout, P.W. Rehrig, W. Hackenberger,S.E. Park, New high temperature morphotropic phase boundary piezoelectrics based on bi (me) o3-pbtio3 ceramics, J. Appl. Phys.40(10R) (2001) p. 5999. https://doi.org/10.1143/JJAP.40.5999
[14] R. Elfrink, T.M.Kamel,M. Goedbloed, S. Matova, D. Hohlfeld, Y. Van Andel,R. Van Schaijk, Vibration energy harvesting with aluminum nitride-based piezoelectric devices, J. Micromech. Microeng. 19(9) (2009)p. 094005. https://doi.org/10.1088/0960-1317/19/9/094005
[15] R. Elfrink, M. Renaud, T.M. Kamel, C. de Nooijer, M. Jambunathan, M. Goedbloed, D. Hohlfeld, S. Matova, V. Pop, L. Caballero, R. van Schaijk , Vacuum-packaged piezoelectric vibration energy harvesters: Damping contributions and autonomy for a wireless sensor system, J. Micromech. Microeng. 20(10) (2010) p. 104001. https://doi.org/10.1088/0960-1317/20/10/104001
[16] L. Fan, S.Y. Zhang, H. Ge, HH. Zhang, Theoretical investigation of acoustic wave devices based on different piezoelectric films deposited on silicon carbide, J. App.PhyS. 114(2) (2013) p. 024504. https://doi.org/10.1063/1.4813491
[17] C. Fei, X. Liu, B. Zhu, D. Li, X. Yang, Y. Yang, Q. Zhou, Aln piezoelectric thin films for energy harvesting and acoustic devices, Nano Energy, 51 (2018)p. 146-161. https://doi.org/10.1016/j.nanoen.2018.06.062
[18] M.H. Frey, D.A. Payne, Nanocrystalline barium titanate: Evidence for the absence of ferroelectricity in sol-gel derived thin layer capacitors, App. Phys Lett. 63(20) (1993)p. 2753-2755. https://doi.org/10.1063/1.110324
[19] S. Fujii, T. Odawara, T. Omori, K.Y. Hashimoto, H. Torii, H. Umezawa,S. Shikata. Low propagation loss in a one-port resonator fabricated on single-crystal diamond. in 2011 IEEE International Ultrasonics Symposium, IEEE. (2011) https://doi.org/10.1109/ULTSYM.2011.0134
[20] H. Gullapalli, V.S. Vemuru, A. Kumar, A. Botello Mendez, R. Vajtai, M. Terrones, S. Nagarajaiah, P.M. Ajayan, Flexible piezoelectric zno-paper nanocomposite strain sensor, Small. 6(15) (2010)p. 1641-1646. https://doi.org/10.1002/smll.201000254
[21] Y. Guo, K.I. Kakimoto, H. Ohsato,. Phase transitional behavior and piezoelectric properties of (Na0.5K0.5)NbO3-LiNbO3 ceramics, App. Phys. Lett. 85(18) (2004) pp.4121-4123. https://doi.org/10.1063/1.1813636
[22] M.A.M. Hatta, M.W.A. Rashid, U.A.A.H. Azlan, N.A. Azmi, M.A. Azam, T. Moriga, Influence of yttrium dopant on the structure and electrical conductivity of potassium sodium niobate thin films, Mater. Res. 19 (2016) p. 1417-1422. https://doi.org/10.1590/1980-5373-mr-2016-0076
[23] S. Hirsch, J. Guo, R. Reiter, S. Papazoglou, T. Kroencke, J. Braun, I. Sack, Mr elastography of the liver and the spleen using a piezoelectric driver, single shot wave field acquisition, and multifrequency dual parameter reconstruction, Magn. Reson. Med. 71(1 (2014) p. 267-277. https://doi.org/10.1002/mrm.24674
[24] E. Hollenstein, M. Davis, M. Damjanovic, N. Setter, Piezoelectric properties of li-and ta-modified (k0.5Na0.5)NbO3 ceramics, App. Phys. Lett. 87(18) (2005)p. 182905. https://doi.org/10.1063/1.2123387
[25] Y. Hou, M. Zhang, G. Han, C. Si, Y. Zhao, J. Ning, A review: Aluminum nitride mems contour-mode resonator, J. Semicond. 37(10) (2016)p. 101001. https://doi.org/10.1088/1674-4926/37/10/101001
[26] H.W. Huang, W.C. Chang, S.J. Lin, Y.L. Chueh, Growth of controllable zno film by atomic layer deposition technique via inductively coupled plasma treatment, J. App. Phys. 112(12) (2012 )p. 124102. https://doi.org/10.1063/1.4768839
[27] S. Humad,R. Abdolvand, G.K. Ho, G. Piazza, F. Ayazi, High frequency micromechanical piezo-on-silicon block resonators. in IEEE International Electron Devices Meeting 2003, IEEE (2003) pp.39-3
[28] A. Illiberi, F. Roozeboom, P. Poodt, Spatial atomic layer deposition of zinc oxide thin films, AACS Appl. Mater. Interfaces, 4(1) (2012) p. 268-272. https://doi.org/10.1021/am2013097
[29] Y. Isogai, M. Miyayama,H. Yanagida, Mechanical response to reducing gases in pzt/zno actuator, J. Ceram. Soc. JAPAN, 103(1193) (1995) p. 96-98. https://doi.org/10.2109/jcersj.103.96
[30] Y. Isogai, M. Miyayama, H. Yanagida, Pzt/zno actuator responding to reducing gases, Sensors and Actuators B: Chemical, 30(1) (1996) p. 47-53. https://doi.org/10.1016/0925-4005(95)01749-L
[31] R.E. Jaeger , L. Egerton, Hot pressing of potassium sodium niobates, J. Am. Ceram. Soc. 45(5) (1962) p. 209-213. https://doi.org/10.1111/j.1151-2916.1962.tb11127.x
[32] R.L. Johnson, Characterization of piesoelectric zno thin films and the fabrication of piezoelectric micro-cantilevers, Ames Lab., Ames, IA (United States) (2005) https://doi.org/10.2172/850081
[33] I. Kanno, Piezoelectric pzt thin films: Deposition, evaluation and their applications. in 2019 20th International Conference on Solid-State Sensors, Actuators and Microsystems & Eurosensors XXXIII (TRANSDUCERS & EUROSENSORS XXXIII), IEEE. (2019) https://doi.org/10.1109/TRANSDUCERS.2019.8808525
[34] A. Khan, Z. Abas,H.S. Kim, I.K. Oh, Piezoelectric thin films: An integrated review of transducers and energy harvesting, Smart Mater. Struct. 25(5) (2016) p. 053002. https://doi.org/10.1088/0964-1726/25/5/053002
[35] D.G. Kim, H.G. Kim, A new characterization of piezoelectric thin films. in ISAF 1998. Proceedings of the Eleventh IEEE International Symposium on Applications of Ferroelectrics (Cat. No. 98CH36245), IEEE. (1998)
[36] Kubo, Kawabata,Kobayashi, Electronic properties of small particles. Annual Review of Materials Science, 1984. 14(1) p. 49-66. https://doi.org/10.1146/annurev.ms.14.080184.000405
[37] H. Kueppers, T. Leuerer, U. Schnakenberg, W. Mokwa,M. Hoffmann, T. Schneller, U. Boettger,R. Waser, PZT thin films for piezoelectric microactuator applications, Sens. Actuator A Phys. 97 (2002) p. 680-684. https://doi.org/10.1016/S0924-4247(01)00850-0
[38] A. Kuoni, R. Holzherr, M. Boillat, N.F. de Rooij, Polyimide membrane with zno piezoelectric thin film pressure transducers as a differential pressure liquid flow sensor, J. Micromech. Microeng. 13(4) (2003) p. S103. https://doi.org/10.1088/0960-1317/13/4/317
[39] F. Kurokawa, R. Yokokawa, H.Kotera, F. Horikiri, K. Shibata, T. Mishima, M. Sato,I. Kanno, Micro fabrication of lead-free (K,Na) NbO3 piezoelectric thin films by dry etching, Micro Nano Lett. 7(12) (2012)p. 1223-1225. https://doi.org/10.1049/mnl.2012.0570
[40] K.W. Kwok, H.L.W.Chan, C.L. Choy, Evaluation of the material parameters of piezoelectric materials by various methods, IEEE Trans. Ultrason. Ferroelectr. Freq. Control. 44(4) (1997) p. 733-742. https://doi.org/10.1109/58.655188
[41] M. Laurenti, S. Stassi, M. Lorenzoni, M. Fontana, G. Canavese, V. Cauda, C.F.Pirri, Evaluation of the piezoelectric properties and voltage generation of flexible zinc oxide thin film,. Nanotechnology. 26(21) (2015) p. 215704. https://doi.org/10.1088/0957-4484/26/21/215704
[42] H.J. Lee, I.W. Kim, J.S. Kim, C.W. Ahn, B.H. Park, Ferroelectric and piezoelectric properties of Na0.52K0.48NbO3 thin films prepared by radio frequency magnetron sputtering, App.Phys. Lett. 94(9) (2009) p. 092902. https://doi.org/10.1063/1.3095500
[43] S. H. Lee, S.S. Lee, J.J. Choi, J.U. Jeon, K. Ro, Fabrication of a high-aspect-ratio nano tip integrated micro cantilever with a zno piezoelectric actuator. in Key Engineering Materials, Trans Tech Publ.270 (2004) pp. 1095-1100 https://doi.org/10.4028/www.scientific.net/KEM.270-273.1095
[44] K. Lefki, G.J.M. Dormans, Measurement of piezoelectric coefficients of ferroelectric thin films, J.App.Phys. 76(3) (1994) p. 1764-1767. https://doi.org/10.1063/1.357693
[45] C. Lei, Z.G. Ye, Lead-free piezoelectric ceramics derived from the K0.5Na0.5NbO3-AgNbO3 solid solution system, App. Phys. Lett. 93(4) (2008) p. 042901. https://doi.org/10.1063/1.2956410
[46] F. Levassort, J.M. Grégoire, M. Lethiecq, K. Astafiev, L. Nielsen, R. Lou-Moeller, W.W. Wolny, High frequency single element transducer based on pad-printed lead-free piezoelectric thick films. in 2011 IEEE International Ultrasonics Symposium, IEEE. (2011) pp. 848-851 https://doi.org/10.1109/ULTSYM.2011.0207
[47] W. Li, Z. Xu, R. Chu, P. Fu, G. Zang, Large piezoelectric coefficient in (Ba1−xCax)(Ti0.96Sn0.04)O3 lead free ceramics, J. Amer.Ceram.Soc. 94(12) (2011) p. 4131-4133. https://doi.org/10.1111/j.1551-2916.2011.04888.x
[48] Y. Lu, N.W. Emanetoglu, Y. Chen, Zno piezoelectric devices, in Zinc oxide bulk, thin films and nanostructures, Elsevier (2006)p. 443-489. https://doi.org/10.1016/B978-008044722-3/50013-0
[49] M. Lukacs, M. Sayer,S. Foster, Single element high frequency (< 50 mhz) pzt sol gel composite ultrasound transducers, IEEE Trans. Ultrason. Ferroelectr. Freq. Control. 47(1)(2000)p. 148-159. https://doi.org/10.1109/58.818757 [50] N. Marandian Hagh, B. Jadidian, A. Safari, Property-processing relationship in lead-free (k, na, li) nbo3-solid solution system, J. Electroceramics. 18(3) (2007) p. 339-346. https://doi.org/10.1007/s10832-007-9171-x [51] K. Matsubara, P. Fons, K. Iwata, A. Yamada, K. Sakurai, H. Tampo, S. Niki, Zno transparent conducting films deposited by pulsed laser deposition for solar cell application,Thin Solid Films. 431 (2003) p. 369-372. https://doi.org/10.1016/S0040-6090(03)00243-8 [52] P. Muralt, Pzt thin films for microsensors and actuators: Where do we stand? , I IEEE Trans. Ultrason. Ferroelectr. Freq. Control. 47(4) (2000) p. 903-915. https://doi.org/10.1109/58.852073 [53] P. Muralt, Piezoelectric thin films for mems, Integr. Ferroelectr. 17(1-4) (1997) p. 297-307. https://doi.org/10.1080/10584589708013004 [54] P. Muralt, Ferroelectric thin films for micro-sensors and actuators: A review, J. Micromech. Microeng. 10(2) (2000) p. 136. https://doi.org/10.1088/0960-1317/10/2/307 [55] P. Muralt, R.G. Polcawich,S. Trolier-McKinstry, Piezoelectric thin films for sensors, actuators, and energy harvesting, MRS Bull. 34(9) (2009)p. 658-664. https://doi.org/10.1557/mrs2009.177 [56] Y. Nakashima, W. Sakamoto, T. Shimura, T. Yogo, Chemical processing and characterization of ferroelectric (K, Na)NbO3 thin films, Jpn. J. Appl. Phys. 46(10S) (2007) p. 6971. https://doi.org/10.1143/JJAP.46.6971 [57] M. Nemoz, R. Dagher, S. Matta,A. Michon, P. Vennéguès, J. Brault, Dislocation densities reduction in mbe-grown aln thin films by high-temperature annealing, J. Cryst. Growth. 461 (2017)p. 10-15. https://doi.org/10.1016/j.jcrysgro.2016.12.089 [58] P.K. Panda, Environmental friendly lead-free piezoelectric materials, J. Mater.Sci. 44(19) (2009) p. 5049-5062. https://doi.org/10.1007/s10853-009-3643-0 [59] S.Y. Pao, M.C. Chao, Z. Wang, C.H. Chiu, K.C. Lan, Z.N. Huang, L.R. Shih, C.L. Wang, Analysis and experiment of hbar frequency spectra and applications to characterize the piezoelectric thin film and to hbar design. in Proceedings of the 2002 IEEE International Frequency Control Symposium and PDA Exhibition (Cat. No. 02CH37234), IEEE. (2002) pp. 27-35 [60] K. Park, D.K. Lee, B.S. , H. Jeon, N.E.Lee, D.Whang, H.J. Lee, Y.J.Kim, J.H. Ahn, Stretchable, transparent zinc oxide thin film transistors. Adv.Func.Mater. 20(20) (2010) p. 3577-3582. https://doi.org/10.1002/adfm.201001107 [61] B. Piekarski, D. DeVoe, M. Dubey, R. Kaul, J. Conrad, Surface micromachined piezoelectric resonant beam filters, Sens. Actuator A Phys. 91(3) (2001)p. 313-320. https://doi.org/10.1016/S0924-4247(01)00601-X [62] A. Qi, L.Y. Yeo, J.R. Friend, Interfacial destabilization and atomization driven by surface acoustic waves, Phys. Fluids. 20(7) (2008) p. 074103. https://doi.org/10.1063/1.2953537 [63] W. Qin, T. Li, Y. Li, J. Qiu, X. Ma, X. Chen, X. Hu, W. Zhang, A high power zno thin film piezoelectric generator, Appl. Surf. Sci. 364 (2016) p. 670-675. https://doi.org/10.1016/j.apsusc.2015.12.178 [64] N.N. Rogacheva, The theory of piezoelectric shells and plates, CRC press. (2020) https://doi.org/10.1201/9781003068129 [65] R. Ruby. 11e-2 review and comparison of bulk acoustic wave fbar, smr technology. in 2007 IEEE Ultrasonics Symposium Proceedings. IEEE. (2007) pp. 1029-1040 https://doi.org/10.1109/ULTSYM.2007.262 [66] R.C. Ruby, P. Bradley, Y. Oshmyansky, A. Chien, J.D. Larson, Thin film bulk wave acoustic resonators (fbar) for wireless applications. in 2001 IEEE Ultrasonics Symposium. Proceedings. An International Symposium (Cat. No. 01CH37263). IEEE.1 (2001) pp. 813-821 [67] N. Setter, D. Damjanovic, L. Eng, G. Fox, S. Gevorgian, S.Hong, A. Kingon, H. Kohlstedt, N.Y. Park, G.B. Stephenson, Ferroelectric thin films: Review of materials, properties, and applications, J. of App. Phys. 100(5) (2006) p. 051606. https://doi.org/10.1063/1.2336999 [68] T.R. Shrout , S.J. Zhang, Lead-free piezoelectric ceramics: Alternatives for pzt? ,J. Electroceram. 19(1) (2007) p. 113-126. https://doi.org/10.1007/s10832-007-9047-0 [69] L. Shu, B. Peng, C. Li, D. Gong, Z. Yang, X.Liu, W. Zhang, The characterization of surface acoustic wave devices based on aln-metal structures, Sensors. 16(4) (2016) p. 526. https://doi.org/10.3390/s16040526 [70] M.T. Todaro, F. Guido, L. Algieri, V.M. Mastronardi, D. Desmaële, G. Epifani, M. De Vittorio, Biocompatible, flexible, and compliant energy harvesters based on piezoelectric thin films, IIEEE Trans Nanotechnol , 17(2) (2018) p. 220-230. https://doi.org/10.1109/TNANO.2017.2789300 [71] S. Vicknesh, S. Tripathy, V.K. Lin, S.J. Chua, B. Kumar, H. Gong, Surface micromachined freestanding zno microbridge and cantilever structures on Si (111) substrates, App. Phys. Lett., 90(9) (2007) p. 091913. https://doi.org/10.1063/1.2642619 [72] N.V. Viet, X.D. Xie, K.M. Liew, N. Banthia, Q. Wang, Energy harvesting from ocean waves by a floating energy harvester, Energy. 112 (2016)p. 1219-1226. https://doi.org/10.1016/j.energy.2016.07.019 [73] Y.Y. Villanueva, D.R. Liu, P.T. Cheng, Pulsed laser deposition of zinc oxide, Thin Solid Films. 501(1-2) (2006) p. 366-369. https://doi.org/10.1016/j.tsf.2005.07.152 [74] J. Voldman, Electrical forces for microscale cell manipulation, Annu. Rev. Biomed. Eng. 8 (2006)p. 425-454. https://doi.org/10.1146/annurev.bioeng.8.061505.095739 [75] Wadell, transmission line design handbook, artech house inc. (1991) p. 291-293. [76] Z. Wang, J.D.N. Cheeke, Characterizing unpoled piezoelectric ceramic film by lamb-waves, IEEE Trans. Ultrason. Ferroelectr. Freq. Control. 46(5) (1999) p. 1094-1100. https://doi.org/10.1109/58.796115 [77] Y. Wang, D. Damjanovic, N. Klein, E. Hollenstein,N. Setter, Compositional inhomogeneity in Li and Ta modified (K, Na)NbO3 ceramics, J. Amer. Ceram. Soc. 90(11) (2007) p. 3485-3489. https://doi.org/10.1111/j.1551-2916.2007.01962.x [78] W.B. Wang, Y.Q. Fu, J.J. Chen, W.P. Xuan, J.K.Chen, X.Z. Wang, P. Mayrhofer, P.F. Duan, A. Bittner, U. Schmid, Alscn thin film based surface acoustic wave devices with enhanced microfluidic performance, J. Micromech. Microeng. 26(7) (2016) p. 075006. https://doi.org/10.1088/0960-1317/26/7/075006 [79] JZ. Wang, X. Li, J.D.N. Cheeke, A modified modal frequency spacing method for coating characterization, J. Acoust. Soc. Am. 104(5) (1998) p. 3119-3122. https://doi.org/10.1121/1.423904 [80] Z. L. Wang, J. Song, Piezoelectric nanogenerators based on zinc oxide nanowire arrays, Science. 312(5771) (2006) p. 242-246. https://doi.org/10.1126/science.1124005 [81] Z. Wang, Y. Zhang, J.D.N. Cheeke, control, Characterization of electromechanical coupling coefficients of piezoelectric films using composite resonators, IEEE Trans. Ultrason. Ferroelectr. Freq. Control. 46(5) (1999) p. 1327-1330. https://doi.org/10.1109/58.796138 [82] S.S. Won, H. Seo, M. Kawahara, S. Glinsek, J. Lee, Y. Kim, C.K. Jeong, A.I. Kingon, S.H. Kim, Flexible vibrational energy harvesting devices using strain-engineered perovskite piezoelectric thin films, Nano Energy. 55(2019) p. 182-192. https://doi.org/10.1016/j.nanoen.2018.10.068 [83] J. Wu, J. Wang, Phase transitions and electrical behavior of lead-free (K0.50Na0.50)NbO3 thin film, AIP. (2009) [84] X. Yan, W. Ren, X. Wu, P. Shi, X. Yao, Lead-free (K, Na)NbO3 ferroelectric thin films: Preparation, structure and electrical properties, J. Alloys Compd. 508(1) (2010) p. 129-132. https://doi.org/10.1016/j.jallcom.2010.08.025 [85]Y. Yoshino, Piezoelectric thin films and their applications for electronics, J. App. Phys. 105(6) (2009) p. 061623. https://doi.org/10.1063/1.3072691 [86]Y. Zhang, Z. Wang, J.D.N. Cheeke, Simulation of electromechanical coupling coefficient by modified modal frequency spectrum method including the electrode effect, Ultrasonic, 38(1-8) (2000) p. 114-117. https://doi.org/10.1016/S0041-624X(99)00172-9 [87] Y.Zhang, Z. Wang, J.D.N.Cheeke, F.S. Hickernell, Direct characterization of zno films in composite resonators by the resonance spectrum method. in 1999 IEEE Ultrasonics Symposium. Proceedings. International Symposium (Cat. No. 99CH37027), IEEE.Vol. 2 (1999) pp. 991-994 [88] S. Zhang, R. Xia,T.R. Shrout, G. Zang, J. Wang, Piezoelectric properties in perovskite 0.948(K0.5Na0.5)NbO3-0.052LiSbO3 lead-free ceramics. J. App. Phys. 100(10) (2006)p. 104108. https://doi.org/10.1063/1.2382348 [89] J. Zhou, M. DeMiguel-Ramos, L. Garcia-Gancedo, E. Iborra, J. Olivares, H. Jin, J.K. Luo, A.S. Elhady, S.R. Dong, D.M. Wang, Characterization of aluminum nitride films and surface acoustic wave devices for microfluidic applications, Sens. Actuators B Chem. 202 (2014) p. 984-992. https://doi.org/10.1016/j.snb.2014.05.066 [90] B. Zhu, J. Xu, Y. Li, T. Wang, K. Xiong, C. Lee, X. Yang,M. Shiiba, S. Takeuchi, Q. Zhou, Micro-particle manipulation by single beam acoustic tweezers based on hydrothermal pzt thick film, AIP Adv. 6(3) (2016) p. 035102. https://doi.org/10.1063/1.4943492