摘要Porous methyl silsesquioxane thin films with low dielectric constant are successfully synthesized by means of the sol-gel spin-coating method. The precursor solutions are prepared by properly mixing the polymer as a matrix with different contents of triacetyl-β-cyclodextrin (TABCD) as a porogen. The chemical structure, dielectric constants, optical constants and void fraction are investigated by the ellipsometric porosimetry, Fourier transform infrared (FTIR) spectroscopy, and other methods. Influences of TABCD and methyl trimethoxysilane (MTMS) on the dielectric properties are discussed. For those samples with higher porogen loading, orientation and electronic polarizations are lower in low and high frequency regions, respectively, because of a considerably smaller number of polar molecules. The FTIR results suggest that high R value (molar ratio of H2O to MTMS) is more advantageous for formation of cage structures and the cage/network structural ratio increases with the increasing R value.
Abstract：Porous methyl silsesquioxane thin films with low dielectric constant are successfully synthesized by means of the sol-gel spin-coating method. The precursor solutions are prepared by properly mixing the polymer as a matrix with different contents of triacetyl-β-cyclodextrin (TABCD) as a porogen. The chemical structure, dielectric constants, optical constants and void fraction are investigated by the ellipsometric porosimetry, Fourier transform infrared (FTIR) spectroscopy, and other methods. Influences of TABCD and methyl trimethoxysilane (MTMS) on the dielectric properties are discussed. For those samples with higher porogen loading, orientation and electronic polarizations are lower in low and high frequency regions, respectively, because of a considerably smaller number of polar molecules. The FTIR results suggest that high R value (molar ratio of H2O to MTMS) is more advantageous for formation of cage structures and the cage/network structural ratio increases with the increasing R value.
[1] Jin C, Luttmer J D, Smith D M and Romas T A 1997 MRS Bull. 22 39 [2] Liu P T, Chang T C, Hsu K C et al 2002 Thin Solid Films 414 1 [3] Furuya A, Yoneda K, Soda E et al 2005 J Vacuum Sci. Technol.B 23 2522 [4] Hijioka K, Ito F, Tagami M et al 2004 Jpn. J. Appl. PhysI 43 1807 [5] Chen W C and Yen C T 2000 J. Vac. Sci. Technol. B 18 201 [6] Xie B and Anthony J and Muscat 2005 Microelectron. Engin. 82 434 [7] Lee L H, Chen W C and Liu W C 2002 J. Polymer Science:A: Polymer Chem. 40 1560 [8] Yim J H, Seon J B, Jeong H D et al 2004 Adv. Funct. Mater. 14 277 [9] Hu Y F, Sun J N and Gidley D W 2005 Chin. Phys. Lett. 22 1488 [10] Han S M and Aydil S S 1998 J. Appl. Phys. 83 2172 [11] Lim S W, Shimogaki Y, Nakano Y, Tada K and Komiyama H 1996 Jpn. J. Appl. Phys. 35 1468 [12] Maex K, Baklanov M R, Shamiryan D et al 2003 J Appl. Phys. 93 8793 [13] Mezza P, Phalippou J and Sempere R 1999 J. NoncrystallineSolids 243 75 [14] Hrubesh L W, Keene L E and Latorre V R 1993 J. Mater.Res. 8 1736 [15] Himcinschi C, Friedrich M, Fuhauf S, Streiter I, Schulz S E et al2002 Anal. Bioanal. Chem. 374 654 [16] Baklanov M R, Mogilnikov K P, G.Polovinkin V and Dultsev F N 2000 J. Vac. Sci. Technol. B 18 1385 [17] Chen W C, Lin A C, Dai B T and Tsai M S 1999 J. Electrochem.Soc. 146 3004 [18]Himcinschi C C, Friedrich M et al 2004 Thin Solid Films 455 433 [19] Sang M H and Eray S A 1998 J. Appl. Phys. 83 2172
2007, Vol. 24 
