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4.08 0.02 nm1.95 0.68 nmAlkanethiolate Bilayer Manipulation Using an Atomic force Microscope Chad I. Drexler, Jevon K. Morris, Kevin B. Moore III, Corey P. Causey, Thomas J. Mullen Department of Chemistry, University of North Florida, Jacksonville, FL 32224, tj.mullen@unf.edu Fabrication of Alkanethiolate Mono- and Multilayer Films

Step 1 is completed by immersing the prepared substrate in a solution of the alkanethiol molecules. The alkanethiolate monolayer generates spontaneously through interatomic interactions between the sulfur and the metal surface. Further use of various iterations of step 2 & 3 allow for the production of multilayers ranging in thickness from a bilayer to multilayers. The Mullen Group , Fall 2013Acknowledgments

15 nN allowed for the selective removal of the top layer of a bilayer. 80 nN allowed for the selective to removal both layers. Nanoshaving Multilayer Films of Varying Thicknesses Nanoshaving was utilized to remove all the layers comprising multilayer films. This allowed the film thickness to be corroborated.Adjacent, chemically patterned, regions shaved at 15 nN and 80 nN allowed for step size comparison of bilayer thickness.

We are grateful for support from UNF Academic Affairs Faculty Development Scholarship Grant and UNF startup support. Selective layer removal of a 16-mercaptohexadecanoic acid bilayer

Total displacement of 16-mercaptohexadecanoic acid multilayer films

Schematic depicting our chemical film assembly process

Principles of Atomic Force Microscopy

Gladys, The Mullen Lab Atomic Force Microscope (AFM)Atomic Force Microscopy (AFM) enables imaging of chemical surfaces with nanoscale resolution. Additionally, the AFM may be employed to generate complex multifunctional nanostructures using Scanning Probe lithographic techniques such as nanoshaving. Au SubstrateSchematic of Atomic Force MicroscopeImaging of Preexistent Chemical Films

Topography of 16-Mercaptohexadecanoic Acid chemical films with specific thicknesses 1-2 nN of force allowed for topographical images of chemical films. Introduction and Motivation The manipulation of molecular structures is of interest in the design and manufacture of chemical films. Alkanethiol molecules are often used in these films, due to their diverse chemistries and ease of assembly upon metal surfaces. Most alkanethiol patterning techniques are limited in their capabilities to produce multilayer chemical films because of the inability of controlling the films thickness. One approach to control chemical film thickness is utilizing the deposition of carboxylic acid terminated alkanethiol molecules and copper ions. Employing this strategy, multilayer films were then characterized using Atomic Force Microscopy (AFM) and by tailoring the force applied to the surface via the AFM tip, we were able to remove the top layers and selectively form complex multifunctional patterns.Schematic of differentshaving options for multilayer patterning based on applied forces.Determining Film Thickness Through NanoshavingConclusions & Future Directions

In this work, the capability to generate complex multilayer chemical films has been demonstrated, along with the implementation of nanoshaving to pattern these structures. In the future, nanoshaving will be utilized to replicate the surface features of alkanethiolate structures and to explore the capability of various polymeric molds. Thereby granting allowance for the replication of complex multifunctional surface features with nanoscale precision.

Step 1Step 3Step 2Nanoshaving involves the application of highforce to a small area on a surface. The applied force disrupts the intermolecular interactions between sulfur and metal ions. Selective Layer Removal and Chemical Patterning

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