A well-ordered, uniform amino (NH(2))-terminated organosilane self-assembled monolayer (SAM) was prepared on a polyimide (PI) substrate, the surface of which had silica-like reactivity. First, through chemical vapor deposition of 1,3,5,7-tetramethylcyclotetrasiloxane and subsequent photooxidation using 172 nm vacuum ultraviolet light, an extremely thin silicon dioxide (SiO(2)) layer about 1 nm thick, which we call an "oxide nanoskin" (ONS), was prepared on a PI substrate. Due to the presence of this ONS layer, the PI surface's properties became almost identical with those of Si covered with native oxide (SiO(2)/Si) without any marked change in surface morphology, as evidenced by zeta-potential measurements, X-ray photoelectron spectroscopy (XPS), and atomic force microscopy (AFM). Next, this ONS-covered PI (ONS/PI) surface was exposed to vapor of a 12.5 vol % solution of N-(6-aminohexyl)(3-aminopropyl)trimethoxysilane (AHAPS) molecules diluted with absolute toluene. On the basis of contact angle analysis, the surface energy of this AHAPS/ONS/PI sample was mostly consistent with that of a SiO(2)/Si substrate covered with an AHAPS-SAM (AHAPS/SiO(2)/Si). On the other hand, the surface energy of an AHAPS-treated PI (AHAPS/PI) substrate was much smaller than that of the AHAPS/ONS/PI substrate due to insufficient surface coverage by the AHAPS molecules. This was also confirmed by lateral force microscopy using photolithographically micropatterned samples. Fabricated micropatterns composed of AHAPS- and SiO(2)-covered regions were clearly imaged on the AHAPS/ONS/PI substrate through their difference in friction, while the friction contrast of the micropatterned AHAPS/PI substrate was unclear. This marked difference in packing density of the AHAPS molecules had a direct influence on the adsorption behavior of palladium colloids and subsequent electroless plating of copper (Cu). As confirmed by AFM and XPS, metallization proceeded only on the AHAPS-covered regions, while the SiO(2)-covered regions remained free of deposits, resulting in the formation of 10-mum-wide Cu microlines on both samples. However, the plating rate achieved on the AHAPS/ONS/PI substrate was about 4.5 times faster than that on the AHAPS/PI substrate and the pattern resolution was considerably fine.

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IntroductionCyclamen (Cyclamen persicum Miller) is a popular plant for horticulture, and for many years, sales of seeds and saplings have benefited the economy of the Ena-Nakatsugawa district, Gifu Prefecture, Japan. This success can be attributed, in part, to the close attention that gardeners pay to diseases affecting the production of seeds and saplings. Several diseases of cyclamen are caused by fungi and bacteria, such as anthracnose (Colletotrichum gloeosporioides), bacterial bud blight (Pseudomonas marginalis pv. marginalis), fusarium wilt (Fusarium oxysporum Schlechtendahl f. sp. cyclaminis), gray mold (Botrytis cinerea), bacterial soft rot (Erwinia carotovora subsp. carotovora), and bacterial leaf blight (Pantoea agglomerans) (Database of Plant Diseases in Japan, NIAS GenBank, https://www.gene.affrc.go.jp/databases-micro_pl_dis-eases_en.php). In particular, anthracnose and bacterial leaf blight frequently occur in Gifu.Among several bacterial species with fungicidal activity, Bacillus subtilis is well characterized (Weller, 1988). Most fungicidal B. subtilis secrete iturin group compounds, which consist of linear alkyl fatty acids and circular depsipeptides, including D-amino acids, as a highly active fungicidal component (Maget-Dana