Effects of annealing on the structure and electrical conductivity of CVD alumina films


Alumina films, 160 nm thick, were deposited on (100) -oriented silicon single-crystal substrates by pyrohydrolysis of aluminum chloride. Such films are candidate gate materials for an improved pH ion-sensitive field-effect transistor (pH-ISFET) for industrial and medical pH measurements. The current-voltage (I–V) characteristics of films annealed for 30 min at temperatures of 850, 1000, and 1175 °C were determined, Annealing at 850 °C produced the optimum I–V behavior for the aluminum oxide pH-sensitive films as evidenced by minimum leakage current and maximum breakdown voltage. The structures of the annealed films were examined using transmission electron microscopy. The anneals at 1000 and 1175 °C caused partial and complete transformation, respectively, of the as-deposited α-alumina to the α-alumina phase. Associated with a-alumina formation was the creation of voids along the grain boundaries and in the grain interiors that provided paths of increased electrical conduction through the alumina films and degraded their dielectric behavior.

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  1. 1

    P. Bergverd, IEEE Trans. Biomed. Eng. BME-15, 70 (1970).

    Article  Google Scholar 

  2. 2

    I. Lundstrom, S. Shivaraman, C. Svensson, and L. Lundkvist, Appl. Phys. Lett. 26, 55 (1975).

    CAS  Article  Google Scholar 

  3. 3

    S. D. Moss, J. B. Smith, P. A. Comte, and C. C. Johnson, in Theory, Design and Biomedical Applications of Solid State Chemical Sensors, edited by P. W. Cheung, D. G. Fleming, W. H. Ko, and M. R. Neuman (CRC Press, West Palm Beach, FL, 1978), pp. 119–134.

  4. 4

    P. W. Cheung, W. H. Ko, D. J. Fung, and A. S. Wong, in Ref. 3, pp. 91–117.

  5. 5

    H. Abe, M. Esashi, and T. Matsuo, IEEE Trans. Electron Devices ED-26, 1939 (1979).

    CAS  Article  Google Scholar 

  6. 6

    D. E. Yates, S. Levine, and T. W. Healy, J. Chem. Soc, Faraday Trans. 70, 1807 (1974).

    CAS  Article  Google Scholar 

  7. 7

    T. W. Healy and L. R. White, Advan. Colloid Interface Sci. 9, 303 (1978).

    CAS  Article  Google Scholar 

  8. 8

    C. D. Fung, P. W. Chung, and W. H. Ko, IEEE Trans. Electron. Devices ED-33, 8 (1986).

    CAS  Article  Google Scholar 

  9. 9

    J. A. Davis and J. O. Leckie, J. Colloid Interface Sci. 74, 32 (March 1980).

    CAS  Article  Google Scholar 

  10. 10

    M. Robinson, J. A. Pask, and D. W. Fuerstenau, J. Am. Ceram. Soc. 47, 516 (1964).

    CAS  Article  Google Scholar 

  11. 11

    J. F. Schenck, IEEE Trans. Electron. Devices ED-23, 1251 (1976).

    Article  Google Scholar 

  12. 12

    E. A. Nechaev and V. A. Volgina, Elektrokhimiya 13(2), 177 (1977).

    CAS  Google Scholar 

  13. 13

    R. Friche and H. Keeger, Z. Naturforsch. 40, 76 (1949).

    Article  Google Scholar 

  14. 14

    A. S. Wong and P. W. Chung, in IEEE Ninth Annual Conference of the Engineering in Medicine and Biology Society (IEEE, New York, 1987), Vol. 2, p. 804.

    Google Scholar 

  15. 15

    F. A. Kroger, in Structure and Properties of MgO and Al2O3 Ceramics, edited by W. D. Kingery (The American Ceramic Society, Columbus, OH, 1984), p. 1.

  16. 16

    T. Sata, J. Appl. Chem. 12, 9 (1962).

    Article  Google Scholar 

  17. 17

    A. S. Barker, Phys. Rev. 132, 1474 (1963).

    CAS  Article  Google Scholar 

  18. 18

    S. C. Carniglia, J. Am. Ceram. Soc. 66(7), 495 (1983).

    CAS  Article  Google Scholar 

  19. 19

    S. K. Tung and R. E. Caffrey, Tran. Metall. Soc. AIME 233, 572 (March 1965).

    CAS  Google Scholar 

  20. 20

    K. Iida and T. Tsujide, Jpn. J. Appl. Phys. 11(6), 840 (1972).

    CAS  Article  Google Scholar 

  21. 21

    W. A. Pliskin and E. E. Conrad, IBM J. 8, 43 (January 1964).

    Article  Google Scholar 

  22. 22

    A. S. Wong and P. W. Cheung, in 1986 IEEE Solid-State Sensors Workshop, Hilton Head Island, South Carolina, 2–5 June 1986 (IEEE, New York, 1986).

  23. 23

    Handbook of Chemistry and Physics (CRC, Cleveland, OH, 1977), p. B-86.

  24. 24

    W. E. Lee and K. P. D. Lagerlof, J. Elec. Microsc. Tech. 2, 247 (1985).

    CAS  Article  Google Scholar 

  25. 25

    S. J. Wilson, Proc. Brit. Ceram. Soc. 28, 281 (June 1979).

    Google Scholar 

  26. 26

    F. W. Dynys and J. W. Halloran, J. Am. Ceram. Soc. 65(9), 442 (September 1982).

    CAS  Article  Google Scholar 

  27. 27

    C. W. White, P. S. Sklad, L. A. Boatner, G. C. Farlow, C. J. McHargue, B. C. Sales, and M. J. Aziz, in Defect Properties and Processing of High-Technology Nonmetallic Materials, edited by Y. Chen, W. D. Kingery, and R. J. Stokes (Materials Research Society, Pittsburgh, PA, 1985), pp. 337–344.

  28. 28

    H. P. Rooksby, in X-ray Identification and Crystal Stucture of Clay Minerals, edited by G. Brown (Mineralogical Society, London, 1961), pp. 354–392.

  29. 29

    National Bureau Standards (U.S.) Circ. 539, 9 (1959).

  30. 30

    G. C. Farlow, P. S. Sklad, C. W. White, C. J. McHargue, and B. R. Appleton, in Ref. 27, pp. 387–394.

  31. 31

    J. K. Doychak, T. E. Mitchell, and J. L. Smialek, in High Temperature Ordered Intermetallic Alloys, edited by C. C. Koch, C. T. Liu, and N. S. Stoloff (Materials Research Society, Pittsburgh, PA, 1985), pp. 475–483.

  32. 32

    S. Wolf, Silicon Processing for the VLSI Era (Lattice, Sunset Beach, CA, 1986), Vol. 1, p. 649.

    Google Scholar 

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Wong, A.S., Michal, G.M., Locci, I.E. et al. Effects of annealing on the structure and electrical conductivity of CVD alumina films. Journal of Materials Research 3, 1002–1009 (1988). https://doi.org/10.1557/JMR.1988.1002

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