Journal of Materials Science

, Volume 41, Issue 1, pp 77–86 | Cite as

Voltage tunable epitaxial Pb x Sr(1− x )TiO3 films on sapphire by MOCVD: Nanostructure and microwave properties

  • S. K. DeyEmail author
  • C. G. Wang
  • W. Cao
  • S. Bhaskar
  • J. Li
  • G. Subramanyam


Frequency and phase agile microwave components such as tunable filters and phase shifters will require ferroelectric thin films that exhibit a nonlinear dependence of dielectric permittivity (ɛ r ) with dc electric bias, as well as a high material (Δɛ r /tan δ) and device (or K-factor in phase shift/dB) figure of merits (FOM). Therefore, voltage tunable (Pb0.3Sr0.7)TiO3 (PST) thin films (90–150 nm) on (0001) sapphire were deposited by metal-organic chemical vapor deposition at rates of 10–15 nm/min. The as-deposited epitaxial PST films were characterized by Rutherford backscattering spectroscopy, X-ray methods, field emission scanning electron microscope, high resolution transmission electron microscopy, Raman spectroscopy, and electrical methods (7–17 GHz) using coplanar waveguide test structures. The epitaxial relationships were as follows: out-of-plane alignment of [111] PST//[0001] sapphire, and orthogonal in-plane alignments of [\(1\bar 10\)] PST//[\(10\bar 10\)] sapphire and [\(\bar 1\bar 12\)] PST//[\(1\bar 210\)] sapphire. The material FOM and device FOM (or K-factor) at 12 GHz were determined to be 632 and ∼13 degrees/dB, respectively. The results are discussed in light of the nanostructure and stress in epi-PST films. Finally, a rational basis for the selection of PST composition, substrate, and process parameters is provided for the fabrication of optimized coplanar waveguide (CPW) phase shifters with very high material and device FOMs.


Sapphire Insertion Loss Rutherford Backscattering Spectroscopy Versus Bias Coplanar Waveguide 
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  1. 1.
    M. J. DALBERTH, R. E. STAUBER J. C. PRICE, C. T. ROGERS, and D. GALT, Appl. Phys. Lett. 72 (1998) 507.CrossRefGoogle Scholar
  2. 2.
    H.-D. WU and F. S. BARNES, Integr. Ferroelectr. 22 (1998) 291.Google Scholar
  3. 3.
    D. S. KORN and H.-D. WU, ibid. 24 (1999) 215.Google Scholar
  4. 4.
    G. SUBRAMANYAM, F. W. VAN KEULS, and F. A. MIRANDA, IEEE Microwave Guided Wave Lett. 8 (1998) 78.CrossRefGoogle Scholar
  5. 5.
    F. W. VAN KEULS, R.R. ROMANOFSKY, D. Y. BOHMAN, M. D. WINTERS, F. A. MIRANDA, C. H. MUELLER, R. E. TREECE, T. V. RIVKIN, and D. GALT, Appl. Phys. Lett. 71 (1997) 3075.CrossRefGoogle Scholar
  6. 6.
    S. S. GEVORGIAN, D. I. KAPARKOV and O. G. VENDIK, IEEE Proc. Microwave, Antennas and Propagation 141 (1994) 501.CrossRefGoogle Scholar
  7. 7.
    A. T. FINDIKOGLU, Q. X. JIA, X. D. WU, G. J. CHEN, T. VENKATESAN and D. W. REAGOR, Appl. Phys. Lett. 68 (1996) 1651.CrossRefGoogle Scholar
  8. 8.
    W. WILBUR et al., Integr. Ferroelectr. 19 (1998) 149.Google Scholar
  9. 9.
    Y. SOMIYA, A. S. BHALLA and L. E. CROSS, Int. J. of Inorg. Mater. 3 (2001) 709.CrossRefGoogle Scholar
  10. 10.
    W. J. KIM, W. CHANG, S. B. QADRI, J. M. POND, S. W. KIRCHOEFER, D. B. CHRISEY and J. S. HORWITZ, Appl. Phys. Lett. 76 (2000) 1185.CrossRefGoogle Scholar
  11. 11.
    R. A. YORK, A. S. NAGRA, P. PERIASWAMY, O. AUCIELLO, S. K. STREIFFER and J. IM, Integr. Ferroelectr. 34 (2001) 177.Google Scholar
  12. 12.
    E. CARLSSON and S. GEVORGIAN, IEEE T. Micro. Theory 47 (1999) 1544.CrossRefGoogle Scholar
  13. 13.
    S. GEVORGIAN, T. MARTINSSON, A. DELENIV, E. KOLLBERG and I. VENDIK, IEEE Proc. Microwave, Antennas and Propagation 144 (1997) 145.CrossRefGoogle Scholar
  14. 14.
    S. NOMURA and S. SAVADA, J. Phys. Soc. Jpn. 10 (1955) 108.CrossRefGoogle Scholar
  15. 15.
    W. J. KIM, H. D. WU, W. CHANG, S. B. QADRI, J. M. POND, S. W. KIRCHOEFER, D. B. CHRISEY and J. S. HORWITZ, J. Appl. Phys. 88 (2000) 5448.CrossRefGoogle Scholar
  16. 16.
    K. WASA and S. HAYAKAWA, in “Handbook of Sputter Deposition Technology” (Noyes Publications, Park Ridge, New Jersey, 1992) p. 175.Google Scholar
  17. 17.
    T. ZHELEVA, K. JAGANNADHAM and J. NARAYAN, J. Appl. Phys. 75 (1994) 860.CrossRefGoogle Scholar
  18. 18.
    K. ABE, N. YANASE, K. SANO and T. KAWAKUBO, Integr. Ferroelectr. 21 (1998) 197.Google Scholar
  19. 19.
    J. MENG, G. ZOU, Y. MA, X. WANG and M. ZHAO, J. Phys.-Condens. Mat. 6 (1994) 6549.CrossRefGoogle Scholar
  20. 20.
    O. G. VENDIK and L. T. TER-MARTIROSYAN, Sov. Phys.-Solid State 36 (1994) 1778.Google Scholar
  21. 21.
    K. ABE and S. KOMATSU, Jap. J. Appl. Phys. 32 (1993) L1157.CrossRefGoogle Scholar
  22. 22.
    C. ZHOU and D.M. NEWNS, J. Appl. Phys. 82 (1997) 3081.CrossRefGoogle Scholar
  23. 23.
    C. BASCERI, S.K. STREIFFER, A.I. KINGON and R. WASER, J. Appl. Phys. 82 (1997) 2497.CrossRefGoogle Scholar
  24. 24.
    H.C. LI, W. SI, A.D. WEST and X.X. XI, Appl. Phys. Lett. 73 (1998) 464.CrossRefGoogle Scholar
  25. 25.
    G.W. DIETZ, W. ANTPOHLER, M. KLEE and R. WASER, J. Appl. Phys. 78 (1995) 6113.CrossRefGoogle Scholar
  26. 26.
    G. W. DIETZ and R. WASER, Thin Solid Films 299 (1997) 53.CrossRefGoogle Scholar
  27. 27.
    S. STREIFFER, C. BASCERI, C.B. PARKER, S.E. LASH, and A.I. KINGON, J. Appl. Phys. 86 (1999) 4565.CrossRefGoogle Scholar
  28. 28.
    N. A. PERTSEV, A. G. ZEMBILGOTOV and A. K. TAGANTSEV, Phys. Rev. Lett. 80 (1998) 1988.CrossRefGoogle Scholar
  29. 29.
    N. A. PERTSEV, A. G. ZEMBILGOTOV, S. HOFFMANN, R. WASER and A.K. TAGANTSEV, J. Appl. Phys. 85 (1999) 1698.CrossRefGoogle Scholar
  30. 30.
    N. A. PERTSEV, A. K. TAGANTSEV and N. SETTER, Phys. Rev. B 61 (2000) R825.CrossRefGoogle Scholar
  31. 31.
    B. DESU, V. P. DUDKEVICH, P. V. DUDKEVICH, I. N. ZAKHARCHENKO and G.L. KUSHLYAN, MRS Symp. Proc. 401 (1996) 195.Google Scholar
  32. 32.
    E. HEGENBARTH and C. FRENZEL, Cryogenics 7 (1967) 331.Google Scholar
  33. 33.
    T. M. SHAW, Z. SUO, M. HUANG, E. LINIGER, R. B. LAIBOWITZ and J. D. BANIECKI, Appl. Phys. Lett. 75 (1999) 2129.CrossRefGoogle Scholar
  34. 34.
    V. L. GUREVICH and A. TAGANTSEV, Adv. Phys. 40 (1991) 719.CrossRefGoogle Scholar
  35. 35.
    A. K. TAGANTSEV, in “Ferroelectric Ceramics: Tutorial Reviews, Theory, Processing, and Applications,” edited by N. Setter and E. L. Colla (Springer-Verlag, New York, LLC, 1992) p. 127.Google Scholar
  36. 36.
    O. VENDIK, L. TER-MARTIROSYAN and S. ZUBKO, J. Appl. Phys. 84 (1998) 993.CrossRefGoogle Scholar
  37. 37.
    J. O. GENTNER, P. GERTHSEN, N. A. SCHMIDT and R.E. SEND, ibid. 49 (1978) 4595.CrossRefGoogle Scholar
  38. 38.
    K.H. HäRDTL, Ceram. Int. 8 (1982) 121.CrossRefGoogle Scholar
  39. 39.
    G. ARLT, U. BOTTGER, and S. WITTE, Appl. Phys. Lett. 63 (1993) 602.CrossRefGoogle Scholar
  40. 40.
    S. MAHAJAN, Prog. Mater. Sci. 42 (1997) 341.CrossRefGoogle Scholar
  41. 41.
    Q. X. JIA, A.T. FINDIKOGLU, D. REAGOR and P. Lu, Appl. Phys. Lett. 73 (1998) 897.CrossRefGoogle Scholar
  42. 42.
    C. K. BARLINGAY and S. K. DEY, Thin Solid Films, 272 (1996) 112.CrossRefGoogle Scholar

Copyright information

© Springer Science + Business Media, Inc. 2006

Authors and Affiliations

  • S. K. Dey
    • 1
    Email author
  • C. G. Wang
    • 1
  • W. Cao
    • 1
  • S. Bhaskar
    • 1
  • J. Li
    • 1
  • G. Subramanyam
    • 2
  1. 1.Department of Chemical and Materials Engineering & Electrical Engineering, Ira A. Fulton School of EngineeringArizona State UniversityTempeUSA
  2. 2.Department of Electrical and Computer EngineeringUniversity of DaytonDaytonUSA

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