• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.28 no.3
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• pp.57-62
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• 2014

In this work, molybdenum oxide films were fabricated by heat-treatment method. Fundamental surface characteristics of molybdenum oxide films were investigated using XRD and Raman spectroscopy. From the results, the optimum MoOx films could be obtained under the conditions of thermal treatment temperature of $550^{\circ}C$, oxidation time of 30 minutes and oxygen flow rate of 250sccm. The thermal treatment method offers a simple and effective route for the synthesis of uniform $MoO_3$ films.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2002.11a
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• pp.460-463
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• 2002

$MoO_3$ thin films were deposited on electrode and heater screen-printed alumina substrates in $O_2$ atmosphere by RF reactive sputtering using Molybdenum metal target. The deposition was performed at $300^{\circ}C$ with 350W of a forward power in an $Ar-O_2$ atmosphere. The working pressure was maintained at $3{\times}10^{-2}mtorr$ and all deposited films were annealed at $500^{\circ}C$ for 5hours. To investigate gas sensing characteristics of the addition doped $MoO_3$ thin film, Co, Ni and Pt were used as adding dopants. The sensing properties were investigated in tenn of gas concentration under exposure of reducing gases such as $H_2$, $NH_3$ and CO at optimum working temperature. Co-doped $MoO_3$ thin film shows the maximum 46.8% of sensitivity in $NH_3$ and Ni-doped $MoO_3$ thin film exhibits 49.7% of sensitivity in $H_2$.

• Korean Journal of Materials Research
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• v.30 no.2
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• pp.81-86
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• 2020

MoO₃ metal oxide nanostructure was formed by hydrothermal synthesis, and a perovskite solar cell with an MoO₃ hole transfer layer was fabricated and evaluated. The characteristics of the MoO₃ thin film were analyzed according to the change of hydrothermal synthesis temperature in the range of 100 ℃ to 200 ℃ and mass ratio of AMT : nitric acid of 1 : 3 ~ 15 wt%. The influence on the photoelectric conversion efficiency of the solar cell was evaluated. Nanorod-shaped MoO₃ thin films were formed in the temperature range of 150 ℃ to 200 ℃, and the chemical bonding and crystal structure of the thin films were analyzed. As the amount of nitric acid added increased, the thickness of the thin film decreased. As the thickness of the hole transfer layer decreased, the photoelectric conversion efficiency of the perovskite solar cell improved. The maximum photoelectric conversion efficiency of the perovskite solar cell having an MoO₃ thin film was 4.69 % when the conditions of hydrothermal synthesis were 150 ℃ and mass ratio of AMT : nitric acid of 1 : 12 wt%.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.16 no.8
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• pp.705-710
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• 2003

MoO$_3$thin films were deposited on electrode of alumina substrates in $O_2$atmosphere by RF reactive sputtering using molybdenum metal target. The deposition was performed at 30$0^{\circ}C$ with 350 W of a forward power in an Ar-O$_2$atmosphere. The working pressure was maintained at 3$\times$10$^{-2}$ torr and all deposited films were annealed at 50$0^{\circ}C$ for 5 hours. The surface morphology of films was observed by using a SEM and crystalline phases were analyzed by using a XRD. To investigate gas sensing characteristics of the doped MoO$_3$thin film, Co, Ni and Pt were used as dopants. The sensing properties were investigated in term of gas concentration under exposure of reducing gases such as H$_2$, NH$_3$and CO at optimum working temperature. Co-doped MoO3 thin film shows the maximum 46.8 % of sensitivity in NH$_3$ and Ni-doped MoO$_3$thin film exhibits 49.7 % of sensitivity in H$_2$.

• The Transactions of the Korean Institute of Electrical Engineers C
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• v.50 no.12
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• pp.607-613
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• 2001

Molybdenum thin films were deposited on the soda lime glass(SLG) substrates by direct-current planar magnetron sputtering, with a sputtering power density of $4.44W/cm^2$. The working pressure was varied from 0.5 mtorr to 20 mtorr to gain a better understanding of the effect of sputtering pressure on the morphology and microstructure of the Mo film. Thin films of $CU(InGa)Se_2$ (CIGS) were deposited on the Mo-coated glass by three stage co-evaporation process. The highest efficiency device was obtained at the maximum value of the tensive stress. The morphology of Mo-coated films were examined by using scanning electron microscopy The film's microstructure, such as the preferred orientation, the full width at half-maximum(FWHM), and the residual intrinsic stress were examined by X-ray diffraction.

• Journal of the Korean Vacuum Society
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• v.12 no.2
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• pp.130-135
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• 2003

Polycrystalline silicon thin films have been used for low cost thin film device application. However, it was very difficult to fabricate high performance poly-Si at a temperature lower than $600^{\circ}C$ for glass substrate because the crystallization process technologies like conventional solid phase crystallization (SPC) require the number of high temperature (600-$1000^{\circ}C$) process. The objective of this paper is to grow poly-Si on flexible substrate using a rapid thermal crystallization (RTC) of amorphous silicon (a-Si) layer and make the high temperature process possible on molybdenum substrate. For the high temperature poly-Si growth, we deposited the a-Si film on the molybdenum sheet having a thickness of 150 $\mu\textrm{m}$ as flexible and low cost substrate. For crystallization, the heat treatment was performed in a RTA system. The experimental results show the grain size larger than 0.5 $\mu\textrm{m}$ and conductivity of $10^{-5}$ S/cm. The a-Si was crystallized at $1050^{\circ}C$ within 3min and improved crystal volume fraction of 92 % by RTA. We have successfully achieved a field effect mobility over 67 $\textrm{cm}^2$/Vs.

• Journal of Integrative Natural Science
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• v.13 no.3
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• pp.87-91
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• 2020

Molybdenum carbide (MoC_x) thin films (TFs) were deposited by reactive radio frequency (rf) magnetron co-sputtering in high vacuum chamber. We compared the properties of MoC_x thin films as the rf power changed on C target. The result of alpha step measurement showed that the thickness of the MoC_x TFs varied from163.3 to 194.86 nm as C power was increased from 160 to 200 W. The crystallinity of MoC_x such as b-Mo₂C, Mo₂C, and diamond like carbon (DLC) structures were observed by XRD. The oxidation states of Mo and C were determined using high resolution XPS spectra of Mo 3d and C 1s were deconvoluted. Molybdenum was consisted of Mo, Mo⁴⁺, and Mo⁶⁺ species. And C was deconvoluted to C-Mo, C, C-O, and C=O species.

• Journal of Information Display
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• v.2 no.3
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• pp.72-77
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• 2001

Amorphous silicon thin-film transistors (a-Si TFTs) were incorporated into Mo-tip-based triode-type field emitters and diode-type ones of carbon nanotubes for an active-matrix cathode (AMC) plate of field emission displays. Also, we developed a novel surface-treatment process for the Mo-tip fabrication, which gleatly enhanced in the stability of field emission. The field emission currents of AMC plates on glass substrate were well controlled by the gate bias of a-Si TFTs. Active-matrix field emission displays (AMFEDs) with these AMC plates were demonstrated in a vacuum chamber, showing low-voltage matrix addressing, good stability and reliability of field emission, and highly uniform light emissions from the anode plate with phosphors. The optimum design of AMFEDs including a-Si TFTs and a new light shield/focusing grid is discussed.

• Proceedings of the Korean Vacuum Society Conference
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• 2012.02a
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• pp.192-192
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• 2012

The next generation electronics need to not only be smaller but also be more flexible. To meet such demands, electronic devices using two dimensional (2D) atomic crystals like graphene, hexagonal boron nitride (h-BN), molybdenum disulfate ($MoS_2$) and organic thin film have been studied intensely. In this talk, I will demonstrate the $MoS_2$ field effect transistor (FET) toward performance enhancement by insulating h-BN substrate.

• 한국신재생에너지학회:학술대회논문집
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• 2009.11a
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• pp.396-396
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• 2009

Chalcopyrite semiconductor $CuInSe_2$ nanoparticles were prepared using a low temperature colloidal route by reacting the starting materials (CuI, $InI_3$ and $Na_2Se$) in solvents. After synthesised $CuInSe_2$ nanoparticles precursors were mixed with organic binder for the viscosity of the precursor slurry to be suitable for the doctor blade method. The mixture of $CuInSe_2$ and binder was deposited onto molybdenum-coated sodalime glass substrates to form thin film. The precursor thin films were preheated on the hot plate to remove remaining solvents and binder material. After subsequent thermal processing of the thin film under a selenium ambient, $CuInSe_2$ absorber layer with grain size significantly lager than that of the nanoparticles was formed.