Hostname: page-component-586b7cd67f-tf8b9 Total loading time: 0 Render date: 2024-11-24T19:59:54.287Z Has data issue: false hasContentIssue false

Volatilization of alkali ions and effects of molecular weight of polyvinylpyrrolidone introduced in solution-derived ferroelectric K0.5Na0.5NbO3 films

Published online by Cambridge University Press:  31 January 2011

Lingyan Wang
Affiliation:
Electronic Materials Research Laboratory, Key Laboratory of the Ministry of Education, Xi'an Jiaotong University, Xi'an 710049, People's Republic of China; and Institute of Materials Research and Engineering, A*STAR (Agency for Science, Technology and Research), Singapore 117602
Kui Yao*
Affiliation:
Electronic Materials Research Laboratory, Key Laboratory of the Ministry of Education, Xi'an Jiaotong University, Xi'an 710049, People's Republic of China; and Institute of Materials Research and Engineering, A*STAR (Agency for Science, Technology and Research), Singapore 117602
Phoi Chin Goh
Affiliation:
Institute of Materials Research and Engineering, A*STAR (Agency for Science, Technology and Research), Singapore 117602
Wei Ren
Affiliation:
Electronic Materials Research Laboratory, Key Laboratory of the Ministry of Education, Xi'an Jiaotong University, Xi'an 710049, People's Republic of China
*
a) Address all correspondence to this author. e-mail: [email protected]
Get access

Abstract

Ferroelectric K0.5Na0.5NbO3 (KNN) thin films were prepared by a chemical solution deposition approach with polyvinylpyrrolidone (PVP) of different molecular weights introduced in the precursor solutions. The volatilization of the alkali ions and the effects of the molecular weight of PVP were examined with x-ray diffraction (XRD), thermal analysis, mass spectrometry, and x-ray photoelectron spectroscopy (XPS). The results clearly showed that the volatilization of the alkali ions mainly happened at moderate temperatures before the crystallization of the KNN perovskite phase. Loss of Na was more significant than K ions during the heating process of KNN. The introduction of PVP with the appropriate molecular weight could effectively promote the crystallization of the KNN perovskite phase at reduced temperature and substantially suppress the loss of the alkali ions before crystallization. Therefore, a high dielectric constant, piezoelectric coefficient, and well saturated ferroelectric hysteresis loops were obtained in the KNN films in which PVP of the right molecular weight were introduced.

Type
Articles
Copyright
Copyright © Materials Research Society 2009

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

REFERENCES

1.Li, J.F., Wang, K., Zhang, B.P., and Zhang, L.M.: Ferroelectric and piezoelectric properties of fine-grained Na0.5K0.5NbO3 lead-free piezoelectric ceramics prepared by spark plasma sintering. J. Am. Ceram. Soc. 89, 706 (2006).CrossRefGoogle Scholar
2.Matsubara, M., Kikuta, K., and Hirano, S.: Piezoelectric properties of (K0.5Na0.5)(Nb1-xTax) O3-K5.4CuTa10O29 ceramics. J. Appl. Phys. 97, 114105 (2005).CrossRefGoogle Scholar
3.Saito, Y., Takao, H., Tani, T., Nonoyama, T., Takatori, K., Homma, T., Nagaya, T., and Nakamura, M.: Lead-free piezoceramics. Nature 432, 84 (2004).CrossRefGoogle ScholarPubMed
4.Zaldo, C., Gill, D.S., Eason, R.W., Mendiola, J., and Chandler, P.J.: Growth of KNbO3 thin films on MgO by pulsed laser deposition. Appl. Phys. Lett. 65, 502 (1994).CrossRefGoogle Scholar
5.Yin, Z., Zhang, P., and Zhang, M.S.: Lattice matching, phase matching, and constituent consistency of optical waveguide Ba2NaNb5O15 films on KTiOPO4. Appl. Phys. Lett. 68, 2303 (1996).CrossRefGoogle Scholar
6.Nakashima, Y., Sakamoto, W., Maiwai, H., Shimura, T., and Yogo, T.: Lead-free piezoelectric (K,Na)NbO3 thin films derived from metal alkoxide precursors. Jpn. J. Appl. Phys. 46, L311 (2007).CrossRefGoogle Scholar
7.Nakashima, Y., Sakamoto, W., Shimura, T., and Yogo, T.: Chemical processing and characterization of ferroelectric (K,Na)NbO3 thin films. Jpn. J. Appl. Phys. 46, 6971 (2007).CrossRefGoogle Scholar
8.Lai, F.P. and Li, J.F.: Sol-gel processing of lead-free (Na,K)NbO3 ferroelectric films. J. Sol-Gel Sci. Technol. 42, 287 (2007).CrossRefGoogle Scholar
9.Tanaka, K., Hayashi, H., Kakimoto, K.I., Ohsato, H., and Iijima, T.: Effect of (Na,K)-excess precursor solutions on alkoxy-derived (Na,K)NbO3 powders and thin films. Jpn. J. Appl. Phys. 46, 6964(2007).CrossRefGoogle Scholar
10.Cho, C.R. and Grishi, A.: Background oxygen effects on pulsed laser deposited Na0.5K0.5NbO3 films: From superparaelectric state to ferroelectricity. J. Appl. Phys. 87, 4439 (2000).CrossRefGoogle Scholar
11.Romanov, M.V., Korsakov, I.E., Kaul, A.R., Stefanvich, S.Y., Bolshakov, I.A., and Wahl, G.: MOCVD of KNbO3 ferroelectric films and their characterization. Chem. Vap. Deposition 10, 318 (2004).CrossRefGoogle Scholar
12.Lu, T., Chen, X.M., Jin, D.Z., and Hu, X.: Dielectric and ferroelectric properties of (1–x) (Na0.5K0.5)NbO3-xBaTiO3 ceramics. Mater. Res. Bull. 40, 1847 (2005).CrossRefGoogle Scholar
13.Wang, L.Y., Yao, K., and Ren, W.: Piezoelectric K0.5Na0.5 NbO3 thick films derived from polyvinylpyrrolidone-modified chemical solution deposition. Appl. Phys. Lett. 93, 092903 (2008).CrossRefGoogle Scholar
14.Yao, K. and Tay, F.E.H.: Measurement of longitudinal piezoelectric coefficient of thin films by a laser-scanning vibrometer. IEEE Trans. Ultrason. Ferroelectr. Freq. Control 50, 113 (2003).Google ScholarPubMed
15.Narendar, Y. and Messing, G.L.: Kinetic analysis of combustion synthesis of lead magnesium niobate from metal carboxylate gels. J. Am. Ceram. Soc. 80, 915 (1997).CrossRefGoogle Scholar
16.Yu, S.H., Yao, K., and Tay, F.E.H.: Structure and properties of (1–x)PZN -xPT thin films with perovskite phase promoted by polyethylene glycol. Chem. Mater. 18, 5343 (2006).CrossRefGoogle Scholar
17.Yu, S.H., Yao, K., Shannigrahi, S., and Tay, F.E.H.: Effects of polyethylene glycol) additive molecular weight on the micro-structure and properties of sol-gel-derived lead zirconate titanate thin films. J. Mater. Res. 18, 737 (2003).CrossRefGoogle Scholar
18.Lee, Y.H., Cho, J.H., Kim, B.I., and Choi, D.K.: Piezoelectric properties and densification based on control of volatile mass of potassium and sodium in (K0.5Na0.5)NbO3 ceramics. Jpn. J. Appl. Phys. 47, 4620 (2008).CrossRefGoogle Scholar
19.Kaufherr, N., Eichorst, D.J., and Payne, D.A.: X-ray photoelectron spectroscopy studies of alkoxide-derived lithium niobate. J. Vac. Sci. Technol., A 14, 299 (1996).CrossRefGoogle Scholar