• Korea-Australia Rheology Journal
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• v.14 no.2
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• pp.71-76
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• 2002

Metal thin films, which are indispensable constituents of ULSI (Ultra Large Scale Integration) circuits, have been fabricated by physical or chemical methods. However, these methods have a drawback of using expensive high vacuum instruments. In this work, the fabrication of tungsten metal film by spin coating was investigated. First of all, inorganic peroxopolytungstic acid (W-IPA) powder, which is soluble in water, was prepared by dissolving metal tungsten in hydrogen peroxide and by evaporating residual solvent. Then, the solution of W-IPA was mixed with organic solvent, which was spin-coated on wafers. And then, tungsten metal films, were obtained after reduction procedure. By selecting an appropriate organic solvent and irradiating UV, the sheet resistance of the tungsten metal film could be remarkably reduced.

• Proceedings of the International Microelectronics And Packaging Society Conference
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• 2001.07a
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• pp.142-145
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• 2001

• 전기의세계
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• v.25 no.1
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• pp.104-107
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• 1976

The switching characteristics of Non-crystalline As-Te-Si-Ge thin film device using Ag, In and Al metal for electrode, has been investigated. Threshold voltage and holding current of each sandwich type device varied due the to formation of the potential barrier in between non crystalline solid and electrode interface.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.22 no.5
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• pp.443-447
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• 2009

Bismuth-antimony-telluride based thermoelectric thin film materials were prepared by metal organic vapor phase deposition using trimethylbismuth, triethylantimony and diisopropyltelluride as metal organic sources. A planar type thermoelectric device has been fabricated using p-type $Bi_{0.4}Sb_{1.6}Te_3$ and n-type $Bi_{2}Te_{3}$ thin films. Firstly, the p-type thermoelectric element was patterned after growth of $5{\mu}m$ thickness of $Bi_{0.4}Sb_{1.6}Te_3$ layer. Again n-type $Bi_{2}Te_{3}$ film was grown onto the patterned p-type thermoelectric film and n-type strips are formed by using selective chemical etchant for $Bi_{2}Te_{3}$. The top electrical connector was formed by thermally deposited metal film. The generator consists of 20 pairs of p- and n-type legs. We demonstrate complex structures of different conduction types of thermoelectric element on same substrate by two separate runs of MOCVD with etch-stop layer and selective etchant for n-type thermoelectric material. Device performance was evaluated on a number of thermoelectric devices. To demonstrate power generation, one side of the device was heated by heating block and the voltage output was measured. The highest estimated power of 1.3 ${\mu}m$ is obtained at the temperature difference of 45 K.

• Advances in nano research
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• v.2 no.3
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• pp.173-177
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• 2014

This study is aimed to the numerical modeling of the surface plasmon-polariton excitation by a layer of active (electrically pumped) quantum dots embedded in a semiconductor, covered with a metal. It is shown that this excitation becomes much more efficient if the metal has a form of a thin (with thickness of several nanometers) film. The cause of this enhancement in comparison with a thick covering metal film is the partial surface plasmon-polariton localized at the metal-semiconductor interface penetration into air. In result the real part of the metal+air half-space effective dielectric function becomes closer (in absolute value) to the real part of the semiconductor dielectric function than in the case of a thick covering metal film. This leads to approaching the point of the surface plasmon-polariton resonance (where absolute values of these parts coincide) and, therefore, the enhancement of the surface plasmon-polariton excitation. The calculations were made for a particular example of InAs quantum dot layer embedded in GaAs matrix covered with an Au film. Its results indicate that for the 10 nm Au film the rate of this excitation becomes by 2.5 times, and for the 5 nm Au film - by 6-7 times larger than in the case of a thick (40 nm or more) Au film.

• Journal of the Microelectronics and Packaging Society
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• v.11 no.4 s.33
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• pp.55-59
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• 2004

We fabricates the $TiO_2$ thin film from anatase phase $TiO_2$ powder having good photocatalytic property using aerosol deposition method at room temperature. Aerosol deposition method, which sprays an aerosol powder with ultrasonic velocity and deposits a thin film on substrate at low temperature, has the advantages of low thermal stress and low cost. To fabricate the $TiO_2$ thin film, the aerosol bath pressure and chamber pressure were 500 torr and 0.4 torr, respectively. The difference of aerosol bath pressure and chamber pressure accelerated the $TiO_2$ nano powder to ultrasonic velocity through the nozzle of $0.4 mm{\times}10 mm$ and $TiO_2$ thin film was finally formed. SS mesh with diameter of 50 mm was used as a substrate to apply the $TiO_2$ thin film to water quality purification. The raw powder was dehydrated for the good dispersion of $TiO_2$ powder. To suppress the formation of second particle, the powder was dispersed for 90 min in alcohol bath by ultrasonic treatment and desiccated. The grain size of $1 {\mu}m$ was observed in $TiO_2$ thin film deposited on SUS mesh by scanning electron microscopy (SEM). The anatase phase of $TiO_2$ thin film was also observed by X-ray diffraction (XRD) and the anatase phase of raw powder was nicely maintained after aerosol deposition. The results are applicable to water treatment filter having photocatalytic reaction.

• 한국생물공학회:학술대회논문집
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• 2001.11a
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• pp.823-826
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• 2001

In the initial process of photosynthesis, a biological electron transfer system, photoelectric conversion occurs and then long-range electron transfer takes place very efficiently in one direction through the biomolecules. The metal/insulator/metal structured device consisting of GFP, viologen, cytochrome c hetero-thin film was presented based on the biomimesis. GFP, viologen, and cytochrome c was used as an electron sensitizer, a mediator, and an electron acceptor. Cytochrome c molecules and viologen molecules were deposited by Langmuir-Blodgett (LB) technique, and GFP molecules were adsorbed by self-assembly method (SAM). Surface morphology of hetero-thin film was analyzed by scanning tunneling microscopy (STM). Local photoswitching effects of a proposed photodiode were verified by current-voltage measurements using hybrid STM/I-V measurement system.

• Journal of the Korean institute of surface engineering
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• v.30 no.4
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• pp.231-238
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• 1997

Tantalum oxide thin filme has an amorphous structure and a high resistivity. Its stoichiometric structure was $Ta_2O_{5.3}$ and the transmission ratio was 80%. The high resistivity of $Ta_2O_{5.3}$ thin film electrolyte made an EC windows without electrical shottness, but the bleached/colored cur rent was very low because of the low ion conductivith. Upon adding moisture into the system, the $\Delta$T increased upto 25 %. proton concentration increase was the main cases to improve optical property. The influence of adding precious or transition metal film(~100 $\AA$ thickness) in $Ta_2O_5$layer on the color change performance was observed. The metal insertion layers had formed hydroxide and they behaved as a stable proton source. The transmission diffrnece and cycle life were greatly enhanced in the case of Ti inssertion.The $\Delta$T was 50% and the cycle life was 18, 000.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2000.11a
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• pp.587-590
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• 2000

This paper presents the characteristics of metal thin-film pressure sensors. The micro pressure sensors consists of a chrom thin-film, patterned on a Wheatstone bridge configuration, sputter-deposited onto thermally oxidized Si wafer an aluminium interconnection layer. The fabricated micro pressure sensors shows a low temperature coefficient of resistance, high-sensitivity, low non-linearity and excellent temperature stability. The sensitivity is 1.16~1.21 mV/V.kgf/$\textrm{cm}^2$ in the temperature range of 25~l0$0^{\circ}C$ and the maximum non-linearity is 0.21 %FS.

• Macromolecular Research
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• v.15 no.3
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• pp.211-215
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• 2007

Hybrid thin film nanostructures composed of metal nanoparticles (NPs) and self-assembled polymer films with different spatial distributions of NPs were analyzed by optical waveguide spectroscopy (OWS). Specifically, the dielectric constants were calculated using effective medium theory for the incorporation of 1 vol% Au NP into the block copolymer (BCP) films having a cylindrical nanodomain morphology. Three cases were considered: uniform distribution of NPs in the film; selective distribution of NPs only in the cylindrical domains; and segregation of NPs to the center of the cylindrical domains. The optical waveguide spectra derived from the calculated dielectric constants demonstrate the feasibility of experimentally distinguishing the composite nanostructures with different inner morphologies in the hybrid metal NP-BCP nanostructures, by the measurement of the dielectric constants using OWS.