Super-low-k SiOCH film (k = 1.9) with extremely high water resistance and thermal stability formed by neutral-beam-enhanced CVD

• Published in: Journal of physics. D, Applied physics Vol. 43; no. 6; p. 065203
• Main Authors: Yasuhara, Shigeo, Sasaki, Toru, Shimayama, Tsutomu, Tajima, Kunitoshi, Yano, Hisashi, Kadomura, Shingo, Yoshimaru, Masaki, Matsunaga, Noriaki, Samukawa, Seiji
• Format: Journal Article
• Language: English
• Published: Bristol IOP Publishing 17.02.2010; Institute of Physics
• Subjects: Chemical vapor deposition; Chemical vapor deposition (including plasma-enhanced cvd, mocvd, etc.); Condensed matter: electronic structure, electrical, magnetic, and optical properties; Cross-disciplinary physics: materials science; rheology; Deposition; Dielectric constant; Dielectric properties of solids and liquids; Dielectric thin films; Dielectrics, piezoelectrics, and ferroelectrics and their properties; Exact sciences and technology; Interlayers; Materials science; Methods of deposition of films and coatings; film growth and epitaxy; Permittivity (dielectric function); Physics; Precursors; Silicon dioxide; Thermal stability; Water resistance; Interfacial layer; TDS; Neutral beam; Hydrocarbons; Experimental device; Deposition rate; Absorption coefficients; Thermal stability; Deposition process; CVD; Silicon oxides; PECVD; Permittivity; Low k dielectric
• ISSN: 0022-3727; 1361-6463
• DOI: 10.1088/0022-3727/43/6/065203

We developed a neutral-beam-enhanced method of chemical vapour deposition (NBECVD) to obtain a lower dielectric constant for the SiOCH interlayer dielectric film while maintaining a reasonable modulus. We achieved a higher deposition rate than that with the precursor of dimethyl-dimethoxy-silane (DMDMOS) we previously reported on by using Ar NBECVD with a precursor of dimethoxy-tetramethyl-disiloxine (DMOTMDS). This is because of the high absorption coefficient of DMOTMDS. Ar NBECVD with DMOTMDS also achieved a much lower dielectric constant than the conventional PECVD film, because this method avoids the precursor dissociation that causes low dielectric film with many linear Si–O structures. We obtained a k value of 1.9 for the super-low- k SiOCH film with an extremely water resistant, and very thermally stable and integration-possible modulus (>4 GPa) by controlling the bias power.