AVS 49th International Symposium
    Surface Science Wednesday Sessions
       Session SS-WeP

Paper SS-WeP2
Functionalization and Patterning of C-H Containing Surfaces Using Oxalyl Chloride

Wednesday, November 6, 2002, 11:00 am, Room Exhibit Hall B2

Session: Surface Science Poster Session
Presenter: G. Husseini, Brigham Young University
Authors: G. Husseini, Brigham Young University
E.T. Sevy, Brigham Young University
M.C. Asplund, Brigham Young University
M.R. Linford, Brigham Young University
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Functionalized and patterned surfaces are of great utility in a variety of areas of science and technology. One particularly useful functional group is the acid chloride, which readily reacts with amines and alcohols. Here we describe a facile gas-phase method of patterning acid chloride groups onto C-H containing surfaces. Basically, a surface that contains C-H groups, e.g., alkylated silicon or polyethylene, is introduced into a flow-through cell that has a quartz window. A mixture of N@sub 2@ carrier gas with a low concentration of oxalyl chloride then flows through the cell at room temperature. The surface is next illuminated with 365 nm light, which is known to cause dissociation of oxalyl chloride. Surface reactions then occur that introduce the -COCl group onto the surface where the surface was illuminated and nowhere else. In particular, clean silicon surfaces are first alkylated with dimethyloctadecylchlorosilane. Acid chloride groups are then introduced onto the surface as mentioned above, followed by characterization using XPS, FTIR, ellipsometry and contact angle goniometry. XPS confirms the presence of chemically shifted carbon. FTIR confirms the presence of carbonyl groups. Optical ellipsometry shows an increase in film thickness. Contact angle goniometry shows a decrease in water contact angles. The main advantage of this work is that silicon surfaces can be easily derivatized with an acid chloride in a one-step-photochemical-gas-phase reaction. We are in the process of extending this work to perform photolithographic patterning of surfaces. The resulting functional groups can be used to attach molecules, including biomolecules such as DNA and peptides.