title: Site-selective electroless metallization on porous organosilica films by multisurface modification of alkyl monolayer and vacuum plasma.
abstract: Taking plasma-enhanced chemical vapor deposited porous SiOCH (p-SiOCH) and octadecyltrichlorosilane (OTS) as model cases, this study elucidates the chemical reaction pathways for alkyl-based self-assembled monolayers (SAMs) on porous carbon-doped organosilica films under N(2)-H(2) vacuum plasma illumination. In contrast to previous findings that carboxylic groups are found in alkyl-based SAMs only by exposure to oxygen-based plasma, this study discovers that, upon exposure to reductive nitrogen-based vacuum plasma, surface carboxylic functional groups can be instantly formed on OTS-coated p-SiOCH films. Particular attention is given to developing a multisurface modification process, starting with the modification of p-SiOCH films by N(2)-H(2) plasma and continuing with SAM deposition and plasma patterning; this ultimately leads to site-selective seeding for the spatially controlled fabrication of Cu-wire metallization by electroless deposition. Plasma diagnosis and X-ray near-edge absorption and Fourier transform infrared spectroscopies show that, by adequately controlling the plasma parameters, the bulk of the p-SiOCH films are free from plasma damage (in terms of degradation in bonding structures and electrical properties); the formation of the seed-trapping carboxylic functional groups on the surface, the key factor for the validity of this new seeding process, is due to a water-mediated chemical oxygenation route.
authors.affiliation: Department of Materials Science and Engineering, Feng Chia University, Taichung 407, Taiwan. gschen@fcu.edu.tw
authors.forename: Giin-Shan
authors.initials: GS
authors.lastname: Chen
authors.forename: Sung-Te
authors.initials: ST
authors.lastname: Chen
authors.forename: Yenying W
authors.initials: YW
authors.lastname: Chen
authors.forename: Yen-Che
authors.initials: YC
authors.lastname: Hsu