Combining conventional lithography with molecular self-assembly for chemical patterning

COLL 84

Mary E. Anderson, meabeth@bu.edu1, Charan Srinivasan, charan@psu.edu2, J. Nathan Hohman3, Mitchell J. Shuster, mjs648@psu.edu4, Erin M. Carter3, Mark W. Horn, mhorn@engr.psu.edu2, and Paul S. Weiss, stm@psu.edu5. (1) Department of Chemistry, Boston University, 590 Commonwealth Ave, Boston, MA 02215, (2) Department of Engineering Science and Mechanics, Pennsylvania State University, 104 Whitmore Lab, University Park, PA 16802, (3) Department of Chemistry, Pennsylvania State University, (4) Department of Physics, Pennsylvania State University, 104 Davey Laboratory, University Park, PA 16802, (5) Departments of Chemistry and Physics, The Pennsylvania State University, 104 Davey Laboratory, University Park, PA 16802
High-quality chemical patterns have been generated with tailored functionality and directed alignment by employing lithographic processing compatible with molecular self-assembly. We have optimized a lithographic method incorporating a resist that permits novel chemical patterning schemes for fabricating multi-component films. The lithographic resist is patterned atop a self-assembled monolayer (SAM), the pattern is transferred by photooxidation, and a different SAM is deposited into the exposed regions. Then the resist is removed while maintaining the functionality that has been patterned onto the substrate. This robust lithographic resist can withstand the photooxidative and chemical conditions utilized for pattern transfer; and it also acts as an important shield protecting against cross-contamination. Uncommon to competing patterning techniques, this method has the advantage of preventing molecular exchange and intercalation, as well as having the ability to align multiple levels of registered patterning, transfer reproducible one-to-one feature sizes, and perform parallel processing. The functionality of these films has been demonstrated using directed colloidal assembly and by surface-bound antibody recognition observed with fluorescence microscopy.