• Macromolecular Research
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• v.13 no.5
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• pp.435-440
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• 2005

This study describes a method where the match of two different length scales, i.e., the patterns from self-assembled block copolymer (<50 nm) and electron beam writing (>50 nm), allow the nanometer scale pattern mask. The method is based on using block copolymers containing a poly(methyl methacrylate) (PMMA) block, which is subject to be decomposed under an electron beam, as a pattern resist for electron beam lithography. Electron beam on self assembled block copolymer thin film selectively etches PMMA microdomains, giving rise to a polymeric nano-pattern mask on which subsequent evaporation of chromium produces the arrays of Cr nanoparticles followed by lifting off the mask. Furthermore, electron beam lithography was performed on the micropatterned block copolymer film fabricated by micro-imprinting, leading to a hierarchical self assembled pattern where a broad range of length scales was effectively assembled, ranging from several tens of nanometers, through submicrons, to a few microns.

• Proceedings of the Korean Society of Tribologists and Lubrication Engineers Conference
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• 2002.10b
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• pp.59-60
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• 2002

In this digest, we briefly review our current molecular dynamics (MD) simulations that utilize both the reactive empirical bond order potential (REBO) and the adaptive intermolecular REBO (AIREBO) potential energy functions. The AIREBO potential includes intermolecular interactions, so that self·assembled monolayers, and liquids, can be modeled. We have examined the mechanical and tribological properties of model self assembled monolayers and amorphous carbon films. Self-assembled monolayers are modeled by covalently bonding hydrocarbon chains to diamond substrates. Because the REBO potentials can model chemical reactions, specific compression and sliding induced chemical reactions were identified.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2002.05a
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• pp.512-515
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• 2002

The lubrication characteristics of SAM(self-assembled monolayer) have been investigated according to the change of surface group and surface temperature treatment with FDTS(1H, 1H, 2H, 2H-Perflurodecyltrichlorosilane) SAM and OTS(octadecyltrichlorosilane) SAM in micro scale. From the experimental results, it was found that OTS SAM gets destroyed at $200^{\circ}C$ and stiction and fiction coefficient increased, but FDTS SAM was stable up to $400^{\circ}C$. Also, it was found that the friction coefficient of normal OTS SAM is lower than that of FDTS SAM, but stiction is vice versa. This work shows the importance of surface group of self-assembled monolayer to control the lubrication characteristics and thermal stability.

• Bulletin of the Korean Chemical Society
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• v.29 no.9
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• pp.1843-1846
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• 2008

• Bulletin of the Korean Chemical Society
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• v.34 no.8
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• pp.2245-2246
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• 2013

• The Transactions of the Korean Institute of Electrical Engineers C
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• v.54 no.2
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• pp.51-54
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• 2005

In this work, the attempt has been made to investigate the morphology of self-assembled dipyridinium dithioacetate on Au(111) substrate by Scanning Tunneling Microscopy(STM). Also, we measured electrical properties(I-V) using Scanning Tunneling Spectroscopy(STS). Sample used in this experiment is dipyridinium dithioacetate, which contains thiol functional group, this structure that can be self-assembled easily to Au(111) substrate. The self-assembly procedure was used for two different concentrations, 0.5 mM/ml and 1 mM/ml. Dilute density of sample by 0.5 mM/ml, 1 mM/ml and observed dipyridinium dithioacetate's image by STM after self-assembled on Au(111) substrate. The structure of STM tip-SAMs-Au(111) substrate has been used measurement for electrical properties(I-V) using STS. The current-voltage(I-V) measurement result, observed negative differential resistance(NDR) properties.

• Proceedings of the KIEE Conference
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• 2004.07c
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• pp.1715-1717
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• 2004

We attempt to investigate morphology of self-assembled dipyridinium dithioacetate on Au(111) substrate by Scanning Tunneling Microscopy(STM). Also, we measured electrical properties using Scanning Tunneling Spectroscopy(STS). Sample that use this experiment acquires thiol function beside quantity by dipyridinium dithioacetate, is structure that can be self-assembled easily to Au(111) substrate. The same self-assembly procedure was used for two different concentrations, 0.5mmol/ml and 1mmol/ml. Dilute density of sample by 0.5mmol/ml, 1mmol/ml and observed dipyridinium dithioacetate's image by STM after self-assembled on Au(111) substrate. The structure of Tip/SAMs/Au(111) has been used measurement for electrical properties(i-v) using STM. The current-voltage measurement result, observed negative differential resistance(NDR) properties.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.19 no.3
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• pp.246-249
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• 2006

We fabricated self-assembled monolayers(SAMs) onto quartz crystal microbalance(QCM) using viologen, which has been widely used as electron acceptor and electron transfer mediator. We determined the time dependence on resonant frequency shift during self-assembly process and observed the morphology of self-assembled monolayers by STM and investigated the electrochemical behavior of SAMs by cyclic voltammetry. Electrochemical deposition of viologen was investigated using electrochemical quartz crystal microbalance(EQCM). The redox reactions of viologen were highly reversible and the EQCM has been employed to monitor the electrochemically induced adsorption of SAMs during the redok reactions. The total frequency change was about 9.5 Hz, and 7.1 Hz. From the data, we could know the mass change was about 10.16 ng and 7.60 ng, respectively. Finally, the EQCM has been employed to monitor the electrochemically induced adsorption of self-assembled monolayers on Au surfaces.

• Proceedings of the Polymer Society of Korea Conference
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• 2006.10a
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• pp.309-309
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• 2006

Latest developments on hybrid nanostructured materials fabricated by applying self-assembly strategies on organic/inorganic nanotemplates are discussed. Within this frame, numerous functional nanomaterials including arrays of composite metal/semiconductor nanoparticles, planar waveguides and functional multilayer thin films are generated using self-assembled polymers as templates or building blocks. In particular, surface plasmon resonance based optical sensing is employed to investigate nanofabrication processes occurring in nanoscale dimention. We also suggest unprecedented pathways to hybrid supramolecular multilayer nanoarchitectures in 1D or 2D geometry via layer-by-layer self-assembly.

• Proceedings of the Polymer Society of Korea Conference
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• 2006.10a
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• pp.293-293
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• 2006

Self-assembled nanostructures of block copolymer thin films have gathered significant attention due to their potential applications as templates for nanofabrication. However the lack of a robust strategy to control the structure formation in thin film geometries has been considered a major obstacle for the practical application. In this presentation 'epitaxial self-assembly' will be introduced as a successful strategy to control the self-assembled nanostructure of block copolymer. Chemically patterned surfaces prepared by advanced lithographic techniques successfully registered nanodomains in block copolymer thin film without any single defect over an arbitrarily large area.