Crystallization of Amorphous and Superhardness Effect in Nano-multilayer Films

doi:10.3724/SP.J.1077.2006.01292

Abstract

Abstract: Template-induced epitaxial crystallization of SiC, TiB₂ and SiO₂ in TiN/SiC, TiN/TiB₂ and TiN/SiO₂ nano-multilayer films and its influence on mechanical properties of the corresponding films were investigated. Results reveal that amorphous SiC, TiB₂ and SiO₂, which are more favorable under sputtering conditions, crystallize at smaller layer thicknesses due to the template effect of c-TiN layers. In particular, SiC crystallizes out in the face-centered cubic structure when its thickness is less than 0.6nm, which improves the crystal quality and structural integrity of the films; While TiB2, with thickness less than 2.9nm, forms hcp structure. The epitaxial orientation relationship between TiN and TiB2 is {111} TiN//{0001} _TiB2, <100> _TiN//<11-20> _TiB2; SiO₂, different from the above two, forms fcc pseudo-crystalline structure under a thickness of 0.9nm. With the crystallization of SiC, TiB₂ and SiO₂, hardness anomalous enhancement, i.e. superhardness effect, appears in those films. This phenomeon of hardness enhancement disappears rapidly when further increase the thickness of SiC, TiB₂and SiO₂ layers, and at the same time, crystallines of SiC, TiB₂ and SiO₂ transform into their amorphous forms, respectively. The formation of these relatively soft amorphous layers, which blocks the coherent growth of the multilayer films, is the main reason of hardness decline at large SiC, TiB₂and SiO₂ layer thicknesses.

Key words: nano-multilayer films, epitaxial growth, crystallization of amorphous, superhardness effect

CLC Number:

O484

KONG Ming,YUE Jian-Ling,LI Ge-Yang. Crystallization of Amorphous and Superhardness Effect in Nano-multilayer Films[J]. Journal of Inorganic Materials, DOI: 10.3724/SP.J.1077.2006.01292.

References

[1] Helmersson U, Todorora S, Barnett S A, et al. J. Appl. Phys., 1987, 62 (2): 481--484.
[2] Chu X, Barnett S A, Wong M S, et al. Surf. Coat. Technol., 1993, 57: 13--18. [3] Setoyama M, Nakayama A, Tanaka M, et al. Surf. Coat. Technol., 1996, 86--87(1--3): 225--230.
[4] Nordin M, Larsson M, Hogmark S. Surf. Coat. Technol., 1998, 106(2--3): 234--241.
[5] Madan M, Kim I W, Cheng S C, et al. Phys. Rev. Lett., 1997, 78(9): 1743--1746.
[6] Yashar P, Chu X, Barnett S A, et al. Appl. Phys. Lett., 1998, 72(8): 987--989. [7] Veno M, Onodera A, Shimomura O, et al. Phys. Rev. B., 1992, 45: 10123--10126.
[8] Ravindra P, Amin S, Max S, et al. J. Mater. Res., 1993, 8: 1922--1927.
[9] Wang Y Y, Wong M S, Chia W J, et al. J. Vac. Sci. Technol. A, 1998, 16(6): 3341--3347.
[10] 胡晓萍, 李戈扬, 顾明元. 材料研究学报, 2003, 17(3): 326--331.
[11] Li G Y, Lao J J, Tian J W, et al. J. Appl. Phys., 2004, 95(1): 92--96.
[12] Kim I W, Li Q, Marks L D, et al. Appl. Phys. Lett., 2001, 78(7): 892--894.
[13] 吴大维, 付德君, 毛先唯, 等. 物理学报, 1999, 48(5): 904--912.
[14] Li D, Chu X, Cheng S C, et al. Appl. Phys. Lett., 1995, 67(2): 203--205.
[15] Li D, Lin X W, Cheng S C, et al. Appl. Phys. Lett., 1996, 68(9): 1211--1213.
[16] Kim C, Qadri S B, Scanlon M R, et al. Thin Solid Films, 1994, 240: 52--55.
[17] 田家万, 韩增虎, 赖倩茜, 等. 机械工程学报, 2003, 39(6): 71--74.
[18] Sproul W D. Science, 1996, 273(16): 889--892.
[19] Yashar P, Barnett S A, Hultman L, et al. J. Mater. Res., 1999, 14(9): 3614--3622.
[20] Sproul W D. Vacuum, 1998, 51(4): 641--646.
[21] 冯端, 师昌绪, 刘治国. 材料科学导论, 第一版, 北京: 化学工业出版社, 2002. 588--589.
[22] Koehler J S. Phys. Rev. B, 1970, 2(2): 547--551.
[23] Kato M, Mori T, Schwartz L H. Acta. Metall., 1980, 28(3): 285--290.
[24] Andson P M, Li C. Nanostructure Mate., 1995, 5(3): 349--362.