Abstract
The present work is focused towards the lowering of the k value of deposited SiO2 thin films by varying solvent concentration i.e. ethanol in the range 4-10 ml. Porous low-k thin films were synthesized by using the sol-gel spinon technique. A non-ionic surfactant polysorbate 80 (Tween 80) was used as a porogen to generate the porosity in the film matrix. The lower values of refractive index and film density were measured to be 1.19 and 0.94 gm/cm3 respectively for 10 ml solvent concentration. Further, the lowest k value of 2.2 and highest porosity percentage of 58.5 % were obtained for the same film due to the dilution of coating solution at higher solvent concentration. The water contact angle of the film was observed to be increased to 106.3° which indicates the transformation of the deposited film surface from hydrophilic to hydrophobic. The change in chemical structure as an effect of solvent concentration is studied by using FTIR. From FTIR spectra the disappearance of Si-OH groups at higher solvent concentration reveals the increase in condensation rate. Overall in this study, the result shows the significant change in structural, chemical and optical properties of the deposited films at 10 ml solvent concentration. Such deposited porous thin films with lower k value and enhanced hydrophobicity can be used as an interlayer dielectric (ILD) for back end of line (BEOL) in CMOS technology.
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References
International Technology Roadmap for Semiconductor, (2012) (www.itrs.net)
Joshi BN, Mhaisagar YS, Mahajan AM (2011) Microelectron Reliab 51:953–958
Schubert U, Husing N (2012) Synthesis of inorganic materials. Wiley Publications
Mhaisagar YS, Joshi BN, Mahajan AM (2014) Microelectron Eng 114:112
Grill A, Gates SM, Ryan TE, Nguyen SV, Priyadarshini D (2014) Appl. Phys. Rev. 1:11306
Joshi BJ, Mahajan AM (2013) Electron Mater Lett 9(6):723–728
Volksen W, Miller RD, Dubois G (2010) Chem Rev 110:57
Lehmann D, Seidel F, Zahn DRT (2014) Springer Plus 3:82
Nostell P, Roos A, Karlsson B (1999) Thin Solid Films 351:170–175
Alam MJ, Cameron DC (2001). Surf Coat Technol 776:142–144
Brinker CJ, Scherer GW (1990) Sol-gel science, the physics and chemistry of sol-gel processing. Academic Press, Inc., CA
6th International Advanced Technologies Symposium (IATS’11), 16-18 May 2011, Elazığ, Turke
Sciortino M, Alonzo G, Ciriminna R, Pagliaro M (2011) Silicon 3(2):77–83
Huang CH, Wang NF, Tsai YZ, Hung CI, Houng MP (2010) Microelectron Eng 87:1735–1740
Kim J-J, Park H-H, Hyun S-H (2001) Thin Solid Films 384:236–242
Zarzycki J (1997) J Sol-Gel Sci Technol 8:17–22
Shokuhfar A, Eghdam E, Alzamani M (2012) Nanosci Nanotechnol 2(1):22–25
Ting C-Y, Sheu H-S, Wu W-F, Wan B-Z (2007) J Electrochem Soc 154(1):G1–G5
Falcaro P, Malfatti L, Kidchob T, Giannini G, Falqui A, Casula MF, Amenitsch H, Marmiroli B, Grenci G, Innocenzi P (2009) Chem. Mater. 21:2055–2061
Lu H-Y, Teng C-L, Yu C-W, Liu Y-C, Wan B-Z (2010) Ind Eng Chem Res 49:6279–6286
Ee WC, Cheong KY (2008) Physica B 403:1763–1769
Hong J-K, Yang H-S, Jo M-H, Park H-H, Choi S-Y (1997) Thin Solid Films 495:308–309
Ting C-Y, Sheu H-S, Wu W-F, Wan B-Z (2007) J Electrochem Soc 154(1):G1–G5
Eckstorff F, Zhu Y, Maurer R, Müller TE, Scholzand S, Lercher JA (2011) Polymer 52:2492
Rao AP, Rao AV, Gurav JL (2008) J Porous Mater 15:507– 512
Mhaisagar YS, Mahajan AM (2013) J Mater Sci Mater Electron 24:4964–4969
Mhaisagar YS, Joshi BN, Mahajan AM (2012) Bull Mater Sci 35:151
Li TY, Yu CH, Lu HY, Wan BZ (2013) ECS J Solid State Sci Technol 2(3):N61–N68
Li X, Dhanabalan A, Meng X, Gu L, Sun X, Wang C (2012) Micro Porous Mesoporous Mater 151:488
Alam AU, Howlader MMR, Deen MJ (2014) J Micromech Microeng 24(035010):1–14
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Pawar, N.B., Mhaisagar, Y.S., Gaikwad, A.S. et al. Synthesis and Characterization of Porogen Based Porous Low-k Thin Films. Silicon 9, 439–446 (2017). https://doi.org/10.1007/s12633-016-9475-z
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DOI: https://doi.org/10.1007/s12633-016-9475-z