• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 1997.04a
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• pp.150-153
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• 1997

Langmuir-Blodgett(LB) technique is one of the ways of fabricating organic ultra-thin films. It is well known that It has the advantage to control the alignment and orientation of the molecules in the films. Metallo-phthalocyanines(MPcs) are sensitive to electron affinitive toxic gaseous molecules, such as NO$_2$, NO, SO$_2$. MPcs are thermal, optical, mechanical, chemical stable. Therefore, it is interesting to prepare phthalocyanine LB films containing copper as a chemical sensor for NO$_2$ and SO$_2$ gas and test their sensitivity to these toxic gases. In this study, thin films of Octa-dodecylosy copper-phthalocyanine were prepared by LB technique. $\pi$-A isotherm, transfer ratio, UV-VIS. spectroscopy of these films were investigated. Also current-voltage(I-V) characteristics of these was auto investigated.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 1997.04a
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• pp.146-149
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• 1997

It is well known that the metallo-phthalocyanines(MPcs) are sensitive to toxic gaseous molecules, such as NO$_2$, NO, SO$_2$. MPcs are thermally, optica1ly, mechanically and chemically stable. Therefore, it is interesting to prepare phthalocyanine LB films containing tin as a chemical sensor for NO$_2$ and SO$_2$ gas and test their sensitivity to these toxic gases. Frist, in this study, ultra thin films of Octa-dodecyloxy tin-phthalocyanine were prepared on various substrates by LB technique. Langmuir-Blodgett(LB) technique is one of the ways of fabricating organic thin films. It has the advantage to control the alignment and orientation of the molecules in the films. $\pi$-A isotherm and transfer ratio of tin-phthalocyanine derivative. UV-VIS. spectroscopy were investigated. Also intrinsic current-voltage(1-V) characteristics of these films was investigated.

• Proceedings of the KIEE Conference
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• 1998.07d
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• pp.1398-1400
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• 1998

The physical properties of the LB films with merocyanine dyes have been published and attract attention due to the possibility of molecular structure control. The evaluation of the thin films was focused for the purpose of molecular structure control. The molecular structure in the case of the thin films with dyes can be examine by optical absorption spectra measurements. In the case of optical absorption spectra of the LB films by the heat treatment at $70^{\circ}C$ in the air, both of the shifted absorption bands decay and a monomer absorption peak of about 530 nm appears instead. And, the formation and dissociation of J-aggregates, anisotropic behavior was no longer observed in the heat treated merocyanine dyes LB films. In the results, study of the merocyanine dyes LB films using optical absorption spectra would an interesting problem of absorption peak shifts and mixed components.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 1996.05a
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• pp.35-42
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• 1996

In this Paper, optical absorption were performed on LB films of binary mixtures of three kinds of merocranine dyes DO, DS, and 6Me-BS, where DS and 6Me-DS form J-like aggregates but not DO in single component films. The observed optical absorption spectra of mixed films were markedly defendent on the combination of dyes. [6Me-DS]$\sub$1-x/[DOl]$\sub$x/ LB films show a sharp red shifted J-like band peak in the whole concentration range. We found the formation of f aggregates in a mixed merocyanine dyes containing a non J-aggregate forming dye DO, in a single component case. Farther investigations on the present and other mixed-dye films will be needed to clarify these points.

• Journal of the Korean Applied Science and Technology
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• v.14 no.2
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• pp.71-79
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• 1997

Ultra-thin films of poly[2-[4-(9-(10-phenyl)anthracenyl)phenoxy)hexyloxy]]-1,4-phenylenevinyleylene(PAHPV) were prepare-d on the hydrophilic ITO substrate by Langmuir-Blodgett(LB) technique. ${\lambda}_{max}$ in the photoluminescence spectrum of these films was 458nm at the excitation wavelength of 365nm before thermal treatment, which comes from diphenylanthracene side chain of PAHPV. It was also confirmed with UV-Vis spectrometer that ultra-thin LB films of PAHPV precursor polymer were prepared well. After thermal treatment for conjugation of PAHPV precursor polymer, ${\lambda}_{max}$ in the photoluminescence spectrum of these films changed to 365nm, which means that the conjugation of these PAHPV films was completed.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 1996.11a
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• pp.401-404
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• 1996

Optical absorption were performed on LB films of binary mixtures of three kinds of merocyanine dyes [DO], [DS], and [6Me-DS], where [DS] and [6Me-DS] from J-like aggregates but not [DO] in single component films. The observed optical absorption spectra of mixed films were markedly dependent on the combination of dyes. [DS]$_{1-x}$ [DO]$_{x}$ LB films show a sharp red shift J-like band peak in the while concentration range. We found the formation of J-aggregates in a mixed merocyanine dyes containing a non J-aggregate forming dye [DO], in a single component case. Further investigations on the present and other mixed dye films will be needed to clarify these points.ts.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.11 no.8
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• pp.581-586
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• 1998

This paper describes athermally stimulated displacement current (TSDC) of arachidic acid(AA) and polyamic acid alkylamine salts(PAAS) Langmuir-Blodgett(LB) films, which is a precursor of polyimide(PI). The TSDC measurements of AA LB film were performed from temperature to about 11$0^{\circ}C$ at a rate of 0.2$^{\circ}C$/ｓ inside a vacuum chamber for a reference. And the TSDC measurements PAAS LB film were performed from room temperature to about 25$0^{\circ}C$ and temperature was increased at the same rate as that of AA LB film. They show that there are TSDC peaks at about 7$0^{\circ}C$ in the arachidic acid LB films, and at about 7$0^{\circ}C$ and 16$0^{\circ}C$ in the PAAs LB films. Results of these measurements indicate the one small peak at 7$0^{\circ}C$ is resulted from a softening of the alkyl group and the large peak at 16$0^{\circ}C$ is possibly due to dipole of C-O group in the PASS molecule. We have calculated the vertical component of the AA and PAAs L film out of the TSDC curves. It shows that the dipole moment of the AA LB film is about 70-mD at 7$0^{\circ}C$. And the dipole moment of PAAS LB film is about 040mD at 7$0^{\circ}C$ and about 200mD at 16$0^{\circ}C$ in the first measurement of TSDC. In the second measurement of TSDC of PASS LB film after cooling down to room temperature, the TSDC peaks are almost disappeared.

• Journal of the Korean Applied Science and Technology
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• v.31 no.3
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• pp.352-358
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• 2014

We were investigated the stability through the electrochemical characteristics of saturated fatty acid(C12, C14, C16, C18) monolayer LB films by cyclic voltammetry. Saturated fatty acid monolayer LB films was deposited on the indium tin oxide(ITO) glass by the LB method. The electrochemical properties were measured by cyclic voltammetry with a three-electrode system in 0.1 N $NaClO_4$ solution. The measuring range was continuously oxidized to 1650 mV, with an initial potential of -1350 mV was reduced. Scanning rates of 50, 100, 150, 200, and 250 mV/s were set. As a result, LB monolayer films of saturated fatty acid were appeared on irreversible processes by the oxidation current from the cyclic voltammogram. Diffusion coefficient(D) of saturated fatty acid(C12, C14, C16, and C18) was calculated 22.231, 2.461, 7.114 and 2.371 ($cm^2s^{-1}{\times}10^{-4}$) in 0.1 N $NaClO_4$ solution, respectively.

• Proceedings of the KIEE Conference
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• 1999.07d
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• pp.1677-1679
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• 1999

Crosslinked LB films of p-HP (p-hexadecoxyphenol) were produced to insulation layers of electronic devices. The fabrication and the electrical properties of LB films according to crosslinking have investigated respectively to Brewster angle microscopy (BAM), Scanning Maxwell-stress microscopy (SMM), current-voltage (I-V) properties and frequency-capacitance (C-F) characteristics. According to crosslinking, conductivity of p-HP LB films have improved and relative dielectric constant have reduced.

• Proceedings of the KIEE Conference
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• 1995.07c
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• pp.1184-1186
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• 1995

The absorption spectra of synthesis of azobenzene containing long chain fatty acids were investigated by UV spectrophotometer in chloroform solution. Also, the pressure-area isotherms of the molecules on the water-air interface were obtained and the LB films were fabricated onto a quartz slides and quartz crystals by the conventional Langmuir-Blodggett(LB) method. The UV absorption spectra of Langmuir-Blodggett(LB) films on quartz slides have been measured. From these measurements, following conclusions were obtained. Azobenzene containing long chain fatty acids show a photoisomerization by irradiation of UV light and visible light alternatively. At the pressure-area isotherms, the value of surface pressure increment were decreased when the number of $C_n$ increased. Also the LB films show a photoisomerization characteristics. So the LB film of azobenzene containing long chain fatty acid has possibility to being applied to functional molecular device such as photomemory and light switching.