Abstract
We report a comparative study of the microstructure of compositionally graded (Ba1-xSrx)TiO3 (BST) films with two compositionally graded directions, up and down, with respect to the substrate, which were deposited epitaxially on (La,Sr)CoO3 (LSCO)-covered MgO(100) single-crystal substrates by pulsed laser deposition. Cross-sectional transmission electron microscopy (TEM) images and electron diffraction show that the graded films grow epitaxially with their (100) plane parallel to the (100) surface of the MgO single-crystal substrate, and with an in-plane orientation relationship of 〈001〉BST//〈001〉LSCO//〈001〉MgO. The crystalline quality and surface morphology of the graded films are closely related to the direction of the compositional gradient built into the graded films. Down-graded films (starting with a BaTiO3 layer at the film/substrate interface) have a much better crystalline quality and a smoother surface than the up-graded films (starting with a (Ba0.75Sr0.25)TiO3 layer at the film/substrate interface). Obviously, the BaTiO3 bottom layer in the down-graded film acts not only as a part of the graded film but also as an excellent seeding layer to enhance the crystallization of the subsequent film layers, resulting in a high crystalline quality of the down-graded film and an enhanced dielectric behavior. Planar (high-resolution) TEM images also demonstrate that down-graded films have a larger, and more uniform, grain size than up-graded films, and that the latter contain voids.
Similar content being viewed by others
References
M. Koizumi, in Proceedings of the First International Symposium on Functionally Graded Materials (FGM), 1990, ed. by M. Yamanouchi, M. Koizumi, T. Hirai, I. Shiota, p. 3
Uemura S (2003) Mater. Sci. Forum 423–424:1
Müller E, Drasar C, Schilz J, Kaysstr WA (2003) Mater. Sci. Eng. A 362:17
Pompe W, Worch H, Epple M, Friess W, Gelinsky M, Greil P, Hempel U, Scharnweber D, Schulte K (2003) Mater. Sci. Eng. A 362:40
Hirai T, Chen L (2003) Mater. Sci. Forum 308–311:509
Suresh S (2001) Science 292:2447
Suresh S, Olsson M, Giannakopoulos A, Padture NP, Jitcharoen J (1999) Acta Mater. 47:3915
Mohammed MS, Auner GW, Naik R, Mantese JV, Schubring NW, Micheli AL, Catalan AB (1998) J. Appl. Phys. 84:3322
Schubring NW, Mantese JV, Micheli AL, Catalan AB, Mohammed MS, Naik R, Auner G (1999) Integr. Ferroelectr. 24:155
Jin F, Auner GW, Naik R, Schubring NW, Mantese JV, Catalan AB, Micheli AL (1998) Appl. Phys. Lett. 73:2838
Schubring NW, Mantese JV, Micheli AL, Catalan AB, Lopez RJ (1992) Phys. Rev. Lett. 68:1778
Brazier M, McElfresh M, Mansour S (1998) Appl. Phys. Lett. 72:1121
Bao DH, Mizutani N, Zhang LY, Yao X (2001) Appl. Phys. Lett. 89:801
Schubring NW, Mantese JV, Micheli AL, Catalan AB (1995) Appl. Phys. Lett. 67:721
Mantese JV, Schubring NW, Micheli AL, Catalan AB, Mohammed MS, Naik R, Auner GW (1997) Appl. Phys. Lett. 71:2047
Slowak R, Hoffmann S, Liedtke R, Waser R (1999) Integr. Ferroelectr. 24:169
Hasenkox U, Hoffmann S, Waser R (1998) J. Sol-Gel Sci. Techn. 12:67
Zhu XH, Chong N, Chan HLW, Choy CL, Wong KH, Liu ZG, Ming NB (2002) Appl. Phys. Lett. 80:3376
Zhu XH, Chan HLW, Choy CL, Wong KH (2002) J. Vac. Sci. Technol. A 20:1796
Zhu XH, Lu SG, Chan HLW, Choy CL, Wong KH (2003) Appl. Phys. A 76:225
Zhu XH, Chan HLW, Choy CL, Wong KH, Xu JJ, Shi SQ (2003) Appl. Phys. A 77:499
Lu SG, Zhu XH, Mak CL, Wong KH, Chan HLW, Choy CL (2003) Appl. Phys. Lett. 82:2877
Brazier M, McElfresh M, Mansour S (1999) Appl. Phys. Lett. 74:299
Chen Z, Arita K, Lim M, Paz de Araujo C (1999) Integr. Ferroelectr. 24:181
Bao DH, Zhang LY, Yao X (2000) Appl. Phys. Lett. 76:1063
Bao DH, Yao X, Zhang LY (2000) Appl. Phys. Lett. 76:2779
Bao DH, Wakiya N, Shinozaki K, Mizutani N, Yao X (2001) Appl. Phys. Lett. 78:3286
Bao DH, Mizutani N, Yao X, Zhang LY (2000) Appl. Phys. Lett. 77:1041
Bao DH, Mizutani N, Yao X, Zhang LY (2000) Appl. Phys. Lett. 77:1203
Boesaru I, Pintilie L (2000) Appl. Phys. Lett. 77:2231
McNeal MP, Jang SJ, Newnham RE (1998) J. Appl. Phys. 83:3288
Shaw TM, Suo Z, Huang M, Liniger E, Laibowwitz RB, Baniecki JD (1999) Appl. Phys. Lett. 75:3044
Lee SBT, Huang CS (2000) Appl. Phys. Lett. 77:124
Zai JW, Chen HD (2004) Appl. Phys. Lett. 84:1162
Author information
Authors and Affiliations
Corresponding author
Additional information
PACS
81.15.-z; 77.55.+f; 68.37.Lp; 61.14.-x
Rights and permissions
About this article
Cite this article
Zhu, X., Chan, H., Choy, CL. et al. A comparative microstructural study of compositionally up- and down-graded (Ba,Sr)TiO3 thin films epitaxially grown on (La,Sr)CoO3-covered MgO(100) substrates by pulsed laser deposition. Appl. Phys. A 82, 709–713 (2006). https://doi.org/10.1007/s00339-005-3419-6
Received:
Accepted:
Published:
Issue Date:
DOI: https://doi.org/10.1007/s00339-005-3419-6