• 한국진공학회:학술대회논문집
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• 한국진공학회 2013년도 제44회 동계 정기학술대회 초록집
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• pp.407-408
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• 2013

Thin transparent conductive oxides (TCOs) having a thickness lower than 30 nm have been widely usedin touch screen panels. However the resistivity of the TCO films significantly increases as the thickness decreases, due to the poor crystallinity at very thin thickness of TCO films. In this study, we have investigated the effect of electron beam irradiation during the sputtering on the electrical properties and transmittance of 30 nm-thick ITO films, which have a different SnO2 atomic percent, prepared by magnetron sputtering at room temperature. Fig. 1 shows the variation of resistivity of ITO films with a different SnO2 atomic percent for both the normal ITO films and electron beam irradiated ITO films. As shows in Fig. 1, the electron beam irradiation to the ITO (SnO2 weight percent 10%) films during the sputtering resulted in a significantly decreased in resistivity from $7.4{\times}10^{-4}{\Omega}-cm$ to $1.5{\times}10^{-4}{\Omega}-cm$ and it also increased in transmittance from 84% to 88% at a wavelength of 550 nm. These results can be attributed to energy transfer from electron to ad-atoms of ITO films during the electron beam irradiated sputtering, which can enhance the crystallinity of 30 nm-thick ITO films. It is strongly indicate that electron beam irradiation can greatly improve the electrical properties and transmittance of very thin ITO films for touch screen panels, flexible displays and solar cells.

• 한국재료학회지
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• 제17권10호
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• pp.516-520
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• 2007

Indium tin oxide, which is used as transparent conducting layer in flexible device, is deposited on PET film by a magnetron sputtering in 300 mm wide roll-to-roll process (vacuum web coating). Sheet resistance, specific resistance and transmittance is differed by sputtering parameters such as working pressures, oxygen partial pressure, and thickness of ITO layer. ITO layer is deposited about 90 nm at roll speed of 0.24 m/min and its sputtering power is 3 kW. From the XRD spectrum deposited ITO layer is verified as amorphous. Under working pressure varied from $3{\times}10^{-4}\;Torr$ to $2{\times}10^{-3}\;Torr$, sheet resistance is lowest at the working pressure of $1{\times}10^{-3}\;Torr$ and its value is from $110\;{\Omega}/{\square}$ to $260\;{\Omega}/{\square}$ at the thickness of 90 nm. Oxygen partial pressure also varies sheet resistance and is optimized at the regime from 0.2% ($1.8{\times}10^{-6}\;Torr$) to 0.6% ($6{\times}10^{-6}\;Torr$). In this oxygen partial pressure sheet resistance is lower than $150\;{\Omega}/{\square}$. As ITO layer thickness increases, sheet resistance decreases down to $21\;{\Omega}/{\square}$ and specific resistance is about $7.5{\times}10.4{\Omega}cm$ in 340 nm thickness ITO layer. Transmittance is measured at the wavelength of 550 nm and is about 90% for 180 nm thickness ITO/PET.

• 한국세라믹학회지
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• 제39권3호
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• pp.233-239
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• 2002

CRT의 전면에 전자파차폐, 정전기 방지 및 저반사 효과를 위해 코팅되는 $SiO_2$/ITO (Indium Tin Oxide) 이층박막의 반사특성에 관하여 연구하였다. 실리카층 및 ITO층의 두께를 변화시키며 나타나는 반사율의 경향을 고찰하고, 이론적인 2층, 3층 저반사코팅의 디자인에 적용시켜 보았다. 입자 상으로 코팅된 ITO는 두께가 증가할수록 기공에 의해 박막의 불균일성이 증가하면서 이론적인 반사모델과의 차이가 커졌다. 실리카와 ITO의 계면에 존재하는 혼합층의 영향으로 인하여 실제측정반사율은 2층으로 디자인한 이론반사율보다 $SiO_2$/$SiO_2$+ITO/ITO의 3층으로 디자인한 반사모델에 보다 잘 적용되었다. 이론적인 저반사 디자인은 근거로 $SiO_2$/ITO 박막의 두께를 90, 65 nm로 조절한 이층막은 기준파장에서 2.5%의 반사율을 나타내었고, 가시광선 영역에서 이론반사율과 유사한 거동을 보였다.

• 한국전기전자재료학회논문지
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• 제35권1호
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• pp.37-43
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• 2022

In this study, we investigated the optical, electrical and exothermic characteristics of ITO/Ag/ITO multilayer structures prepared with various Ag thicknesses on quartz and PI substrates. The transparent conducting properties of the ITO/Ag/ITO multilayer films depended on the thickness of the mid-layer metal film. The ITO/Ag (14 nm)/ITO showed the highest Haccke's figure of merit (FOM) of approximately 19.3×10^-3 Ω^-1. In addition, the exothermic property depended on the substrate. For an applied voltage of 3.7 V, the ITO/Ag (14 nm)/ITO multilayers on quartz and PI substrates were heated up to 110℃ and 200℃, respectively. The bending tests demonstrated a comparable flexibility of the ITO/Ag/IT multilayer to other transparent electrodes, indicating the potential of ITO/Ag/ITO multilayer as a flexible transparent conducting heater.

• 반도체디스플레이기술학회지
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• 제18권4호
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• pp.100-104
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• 2019

The 'ITO/Ag/ITO' multilayers as a highly conductive and transparent electrode, even with the optimum thickness conditions, the transmittances were much lower than those of a single ITO layer on some ranges of the visible wavelength. In order to improve the transmittance, Ag layer was formed with mesh structure. Where, the thickness of the Ag layer was about 10 nm and the space between the Ag lines was varied from 2.9 ㎛ to 19.6 ㎛ with the fixed Ag width of about 1.2 ㎛ in order to vary an open ratio of the Ag mesh structure. The transmittance and sheet resistance in the ITO/Mesh-Ag/ITO multilayer structure were analyzed depending on the open ratio. As a result, a trade off in the open ratio was necessary in order to obtain the transmittance as high as possible and the sheet resistance as possible low. By the open ratio of about 86%, in the ITO/Mesh-Ag/ITO multilayer structure, the transmittance was nearly same as the single ITO layer and the sheet resistance was about 62.3 Ω/.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2000년도 하계학술대회 논문집
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• pp.427-431
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• 2000

ITO (indium tin oxide) thin films on PET (polyethylene terephthalate) and glass substrates have been deposited by a dc magnetron sputtering without heat treatments such as substrate heater and post heat treatment. Each sputtering parameter during the sputtering deposition is an important factor for the high quality of ITO thin films deposited on polymeric substrate. Particularly, the material, electrical and optical properties of as-deposited ITO oxide films are dominated by sputtering power, oxygen partial pressure and films thickness. As the experimental results, the XRD patters of ITO films are influenced by sputtering power and pressure. As the power and pressure are increased, (411) peak is grown suddenly. the electrical resistivity is also increased, as the sputteing power and pressure are increased. Transmittance of ITO thin films in visible light ranges is lowered with increasing the sputtering power and film thickness. Reflectance of ITO films in infia-red region is decreased, as the power and pressure is increased.

• 제어로봇시스템학회논문지
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• 제14권4호
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• pp.336-341
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• 2008

Recently, research on a flat panel display(FPD) has focused on organic light-emitting display(OLED) which has wide angle of view, high contrast ratio and low power consumption. ITO(Indium-Tin-Oxide) films are the most widely used material as a transparent electrode of OLED and also in many other display devices like LCD or PDP. The performance and efficiency of OLED is related to the surface condition of ITO coated glass substrate. The typical surface defect of glass substrate is measured for electric characteristics and physical condition for transmittance and roughness. Since ITO coated glass substrate can be destroyed for inspection about surface roughness, sheet resistance, film thickness and transmittance, precise fabrication condition should be made based on the estimated relationship. In this paper, ITO films were prepared on the commercial glass substrate by the Ion-Plating method changing the partial pressure of gas(Ar, 02) and the chamber temperature between $200^{\circ}C$ and $300^{\circ}C$. The characteristics of films were examined by the 4-point probe, supersonic thickness measurement, transmittance measurement and AFM. We estimated the relationship between processing parameters(Ar gas, O2 gas, Temperature) and properties of ITO films (Sheet Resistance, Film Thickness, Transmittance, Surface Roughness).

• 한국표면공학회지
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• 제42권1호
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• pp.21-25
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• 2009

Using an evaporation system, $SiO_2$ was deposited as a buffer layer between a PET substrate and a ITO layer and then ITO/$SiO_2$/PET layers were annealed for 1.5 hours at the temperature of $180^{\circ}C$. Adhesion and electro-optical properties of ITO films were studied with thickness variance of a $SiO_2$ buffer layer. As a result of introduction of the $SiO_2$ buffer layer, sheet resistance and resistivity increased and a ITO film with optimum sheet resistance ($529.3{\Omega}/square$) for an upper ITO film of resistive type touch panel could be obtained when $SiO_2$ of $50{\AA}$ was deposited. And it was found that ITO films with $SiO_2$ buffer layer have higher transmittance of $88{\sim}90%$ at 550 nm wavelength than ITO films with no buffer layers and the transmittance was enhanced as $SiO_2$ thickness increased from $50{\AA}$ to $100{\AA}$. Adhesion property of ITO films with $SiO_2$ buffer layers became better than ITO films with no buffer layers and this property was independent of $SiO_2$ thickness variance ($50{\sim}100{\AA}$). By depositing a $SiO_2$ buffer layer of $50{\AA}$ on the PET substrate and sputtering a ITO thin film on the layer, a ITO film with enhanced adhesion, electro-optical properties could be obtained.

• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2005년도 International Meeting on Information Displayvol.II
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• pp.1556-1559
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• 2005

Indium-tin oxide (ITO) films were deposited by a low-frequency (LF, 100 Hz) magnetron sputtering on glass substrates at the room temperature. The effects of the film thickness on the structural, electrical and optical properties of ITO films were investigated. With the film thickness the films reveal better crystallinity, showing both (222) and (400) pla nes in the XRD pattern. The optical transmittance and the sheet resistance of the films decreased with the increasing thickness. In addition, the electrical properties of ITO films were improved after annealing in a vacuum.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1996년도 하계학술대회 논문집 C
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• pp.1421-1423
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• 1996

In this study, the effect of solar cell cover glass on the solar cell performance is evaluated. Silicon solar cell (active area:4*6cm, efficiency:12.6% at AMO condition) is used for this study. ITO(Indium tin Oxide) film thickness of the ITO/AR/substrate glass/solar cell structure samples are $40{\AA}$, $60{\AA}$, $160{\AA}$, $240{\AA}$ respectively. The solar cell maximum output power on the stacking structure variations showed 465mW in the AR/ITO/substrate glass/solar cell, and minimum output power showed 403mW in the AR/substrate glass/solar cell. The maximum output power of the solar cell on the ITO thickness variations of the ITO/AR/substrate glass/solar cell showed 460mW at $40{\AA}$ then decrease output power as ITO thickness increase. For environment tests, all samples are exposed UV light in the vacuum chanber. The output power degradation of AR(UVR)/substrate glass/solar cell stacking structure is small compared with ITO/AR(UVR)/substrate glass/solar cell stacking structure.