• Journal of the Semiconductor & Display Technology
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• v.16 no.2
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• pp.66-69
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• 2017

In this paper, solution based Indium Zinc Oxide thin film transistors (IZO TFTs) were fabricated with PVP gate dielectric. To enhance the electrical properties, UV-O3 treatment is proposed on solution based IZO TFTs. The gate leakage current and interface trap density is compatible with conventional ZnO-based TFT with inorganic gate insulator. Especially, the UV-treated device shows improved electrical characteristics compared to the untreated device. These results can be explained by X-ray photoelectron spectroscopy (XPS) analysis, which shows that the oxygen vacancy of UV-O3 treatment is higher than that of no treatment.

• Journal of the Korean Vacuum Society
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• v.8 no.1
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• pp.20-25
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• 1999

The effect of different plasma surface preparation and oxidation processes for the formation of $SiO_2-Si$(100) interfaces was studied using angle resolved uv-photoelectron spectroscopy. The surface preparation processes included ex situ preclean as well as in situ hydrogen plasma, which were compared to the processes of UHV annealing at high temperature. The spectral position of the oxide valence band features, with respect to the Fermi level. Were found to shift according to the different processes of surface preparation and oxidation. The shifts were analyzed in terms of band bending in the Si. Origins of the spectral shifts were considered to include defects at the $SiO_2Si$ interfaces and surface morphology(roughness) dependent on the surface preparation processes. From comparison of the ARUPS results of the various processes, it was concluded that the interface bonding of the silicon oxide-showed the lowest band bending.

• Journal of the Microelectronics and Packaging Society
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• v.27 no.4
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• pp.77-81
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• 2020

Resistive RAM (ReRAM) is a strong candidate for the next-generation nonvolatile memories which use the resistive switching characteristic of transition metal oxides. The resistive switching behaviors originate from the redistribution of oxygen vacancies inside of the oxide film by applied programming voltage. Therefore, controlling the oxygen vacancy inside transition metal oxide film is most important to obtain and control the resistive switching characteristic. In this study, we introduced an applying electric field into photochemical metal-organic deposition (PMOD) process to control the oxidation state of metal oxide thin film during the photochemical reaction by UV exposure. As a result, the surface oxidation state of FeOx film could be successfully controlled by the electric field-assisted PMOD (EFAPMOD), and the controlled oxidation states were confirmed by x-ray photoelectron spectroscopy (XPS) I-V characteristic. And the resistive switching characteristics with the oxidation-state of the surface region could be controlled effectively by adjusting an electric field during EFAPMOD process.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2009.06a
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• pp.49-49
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• 2009

Nanocomposites of gold nanoparticles and multi-walled carbon nanotubes (MWNTs) were prepared by electrostatic interaction. Gold nanopartic1es were stabilized by polyvinylpyrrolidone (PVP), sodium dodecyl sulfate (SDS) and poly(sodium-4-styrenesulfonate) (PSS) in aqueous medium, and MWNTs were modified by poly(diallyldimethylammonium)chloride (PDDA) in water. The as-perpared Au-MWNT nanocomposites were structurally and electrically characterized by transmission electron microscopy (TEM), field emission scanning electron microscopy (FE-SEM), X-ray diffraction (XRD), UV/Vis spectroscopy, X-ray photoelectron spectroscopy (XPS) and cyclo voltammetry (CV). UV/Vis spectra of Au-MWNT nanocomposites showed the characteristic surface plasmon bands in the range of ~515nm, depending on the stabilizers. There is only slight change on the band shape with variation of stabilizing agents for gold nanoparticles. Through FE-SEM and TEM images, the distribution of gold, nanoparticles on the sidewalls of MWNTs was deliberately investigated on Au-MWNT nanocomposites treated with different stabilizers. XPS and CV showed redistribution of electron densities and changes in the binding energy states of nanopartic1es in nanocomposite respectively.

• Proceedings of the Korean Vacuum Society Conference
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• 2010.02a
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• pp.345-345
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• 2010

Thin film of $TiO_2$ deposited on carbon paper was fabricated by atomic layer deposition (ALD) using titanium isopropoxide (TTIP) and $H_2O$ as precursors. In this work, the photocatalytic activities of $TiO_2$ films with and without e-beam treatment were compared. The samples were treated by e-beam using e-beam energy of 1MeV and exposure range between 5 and 15kGy. The photocatalytic activity was evaluated by the photocatalytic degradation of methyleneblue (MB) under UV irradiation (365nm) at room temperature using an UV-vis spectroscopy. The surface properties were characterized by scanning electron microscope (SEM) and X-ray photoelectron spectroscopy (XPS). The sample treated by the low radiation dose has more catalytic activity than other ones. SEM images show that the high radiation dose caused the $TiO_2$ to aggregation on carbon paper. Due to the aggregation of $TiO_2$, the partially exposed carbon paper was oxidized.

• KIEE International Transactions on Electrophysics and Applications
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• v.12C no.4
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• pp.214-219
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• 2002

The influence of ultraviolet (UV) irradiation and corona on the surface degradation of high temperature vulcanized (HTV) silicone rubber used for outdoor insulation through measuring surface voltage decay after corona charging, surface resistivity, contact angle and X-ray photoelectron spectroscopy (XPS) analysis was studied. The surface resistivity calculated by the surface voltage decay was compared with a value directly obtained from the three electrode method having the guard ring electrode. A good agreement between the two methods for surface resistivity was obtained. UV treated specimens showed the slower decrease of surface voltage decay, while the corona exposed specimens showed a dramatically faster decrease. Although both artificial treatments cause the same oxidative products, which was confirmed with XPS, we could distinguish the difference between the reactions of the two treatments by monitoring the surface voltage decay on corona-charged specimen. In addition, we could derive the specific surface states of the silicone rubber treated by accelerated artificial aging factors and the degradation process.

• Proceedings of the Korean Vacuum Society Conference
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• 2014.02a
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• pp.352.2-352.2
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• 2014

In this present work, we report a Cu-Mn alloy as a materials for the self-forming barrier process. And we investigated diffusion barrier properties of self-formed layer on low-k dielectrics with or without UV curing treatment. Cu alloy films were directly deposited onto low-k dielectrics by co-sputtering, followed by annealing at various temperatures. X-ray diffraction revealed Cu (111), Cu (200) and Cu (220) peaks for both of Cu alloys. The self-formed layers were investigated by transmission electron microscopy. In order to compare barrier properties between Mn-based interlayer interlayer, thermal stability was measured with various low-k dielectrics. X-ray photoelectron spectroscopy analysis showed that chemical compositions of self-formed layer. The compositions of the Mn based self-formed barriers after annealing were determined by the C concentration in the dielectric layers.

• Journal of the Korean Vacuum Society
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• v.7 no.s1
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• pp.190-196
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• 1998

Amorphous ternary $Si_xC_yN-z$ thin films were obtained by plasma enhanced chemical vapor deposition(PECVD) using $N_2, SiH_4 \;and \;C_2H_4$ as the reaction sources. The chemical state were characterized by x-ray photoelectron spectroscopy (XPS) and Fourier transform infrared spectroscopy(FTIR). The optical properties of the thin films were investigated by UV-visible spectrophotometer and ellipsometer, and the optical band gaps of thin films were determined from corresponding transmittance spectra following Tauc equation.

• Proceedings of the Korean Vacuum Society Conference
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• 2013.02a
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• pp.282-282
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• 2013

The antimony sulfide ($Sb_2S_3$) thin films were deposited using the gas phase method which known as atomic layer deposition (ALD) on mesoporous micro-films. Tris (dimethylamido) antimony (III[$(Me_2N)_3Sb$] and hydrogensulfide ($H_2S$) were used as precursors to deposit $Sb_2S_3$. Self-terminating nature of $(Me_2N)_3Sb$ and $H_2S$ reaction were demonstrated by growth rate saturation versus precursors dosing time. Absorption spectra and extinction coefficient were investigated by UV-VIS spectroscopy. Scanning electron microscopic analysis and X-ray photoelectron spectroscopy (XPS) depth profile were employed to determine the conformal deposition.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2008.11a
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• pp.61-61
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• 2008

Nanocomposites of metal (gold and silver) nanoparticles and multi-walled carbon nanotubes (MWNTs) were prepared with the assistance of various stabilizers for metals and MWNTs. Especially common surfactants such as poly(4-vinylpyridine) (PVP), sodium dodecyl sulfate (SDS), poly(sodium 4-styrene sulfonate) (PSS), and poly(diallyldimethylammonium) chloride (PDDA) were used for the sample preparation. Metal/MWNT nanocomposites were structurally characterized in by transmission electron microscopy (TEM), x-ray photoelectron spectroscopy (XPS), x-ray diffraction (XRD), UV/Vis spectroscopy. In addition, the electrical properties of the nanocomposites were studied by cyclic voltammetry (CV).