Pattern creation on Preformed SAMs by Smart Contact Lithograhy
Xue-Mei Li, Jurriaan Huskens, David N. Reinhoudt
Laboratory of Supramolecular Chemistry and Technology, MESA+ Research Institute
University of Twente, P.O. Box 217, 7500 AE Enschede, The Netherlands
Email: x.m.li@ct.utwente.nl; homepage: http://smct.ct.utwente.nl
Self-assembled monolayers (SAMs) on gold are attractive for the development of
sensors,1,2 interfaces,3 and nanofabrication.4-6 Here we report the use of reactive contact
lithography to create patterns on a preformed -functionalized self-assembled monolayer
on gold.
5-Mercapto-2-benzimidazole sulfonic acid sodium salt (MBS-Na+) was used as a
ligand for gold nanoparticles. These monolayer-protected gold colloids (MPCs) were
transformed into the catalytically active H+-form by ion exchange. This colloid-bound
catalyst hydrolyzed the TMS adsorbate (TMS-OC11H22S)2 both in solution and when selfassembled on gold surfaces. The colloidal particles were deposited on the same SAM
surfaces by microcontact printing. Thus, local hydrolysis of the TMS adsorbate created
patterns on the SAM surfaces.
Furthermore, MBS-Na+ was used to form a self-assembled monolayer on a
metallized PDMS stamp. After transformation from Na+ to H+ form, this stamp was
brought into contact with the TMS adsorbate monolayer. The surface was imaged by
contact mode AFM (Figure 1) showing a patterned surface has been created, which
confirmed the reactivity of reactive stamp.
Figure 1. Contact mode AFM images (acquired in air) of TMS adsorbate SAM
after contact with a functionalized PDMS stamp for 15 min. (left, height profile; middle
and right, friction)
References
1. Huisman, B.-H.; Kooyman, R. P. H.; van Veggel, F. C. J. M.; Reinhoudt, D. N. Adv.
Mater. 1996, 8, 561-564.
2. Schierbaum, K. D.; Weiss, T.; van Velzen, E. U. T.; Engbersen, J. F. J.; Reinhoudt,
D. N.; Gopel, W. Science 1994, 265, 1413-1415.
3. Shon, Y. S.; Lee, S.; Perry, S. S.; Lee, T. R. J. Am.Chem. Soc. 2000, 122, 1278-1281.
4. Díaz, D. J.; Hudson, J. E.; Storrier, G. D.; Abruña, H. D.; Saudararajan, N.; Ober, C.
K. Langmuir 2001, 17, 5932-5938.
5. Xu, S.; Miller, S.; Laibinis, P. E.; Liu, G. Y. Langmuir 1999, 15, 7244-7251.
6. Liu, G. Y.; Xu, S.; Qian, Y. Acc. Chem. Res. 2000, 33, 457-466.