title: Kinetic control of the photochemical reactivity of hydrogen-terminated silicon with bifunctional molecules.
abstract: Carboxy-terminated crystalline silicon surfaces are of fundamental importance for biochip fabrication because of their reactivity toward biological macromolecules. To explore the feasibility of direct attachment of bifunctional molecules (e.g., omega-alkenoic acids) to hydrogen-terminated silicon crystal (H-Si) via Si-C linkages, we have investigated the photoreactivities of the alkene (-CH=CH(2)) and carboxy (-COOH) terminal groups of 1-dodecene, undecanoic acid, and undecylenic acid toward H-Si. The alkene terminus was found to react substantially faster than the carboxy terminus under UV irradiation (at 350 nm). By controlling the reaction time, high-quality carboxy-terminated monolayers, comparable to those formed by ester hydrolysis, can be obtained from a direct, one-step photochemical reaction between H-Si and undecylenic acid.
authors.affiliation: Department of Chemistry, Simon Fraser University, Burnaby, British Columbia V5A 1S6, Canada.
authors.forename: Hidehiko
authors.initials: H
authors.lastname: Asanuma
authors.forename: Gregory P
authors.initials: GP
authors.lastname: Lopinski
authors.forename: Hua-Zhong
authors.initials: HZ
authors.lastname: Yu