• Journal of the Korean Vacuum Society
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• v.7 no.s1
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• pp.7-14
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• 1998

Details are given of an study of the characteristics of field-induced electron emission from hydrogen-free high $sp^3$ content(>90%) amorphous diamond (a-D) film deposited on heavily doped ($\rho$<0.01 $\Omega\cdot\textrm{cm}$) n-type monocrystalline Si(111) substrate. It is demonstrated that a-D film has excellent electron field emission properties. Emission current can reach 0.9 $\mu$A at applied field as low as 1 V/$\mu\textrm{m}$, and emission current density can be obtained about several mA/$\textrm{cm}^2$. The emission current is stable when the beginning current is at 50 $\mu$A within 72 hours. Uniform fluorescence display of electron emission from whole face of the a-D film under the electric field of 10~20 V/$\mu\textrm{m}$ was also observed. It can be considered that the contribution of excellent electron emission property results from its smooth, uniform, amorphous surface and high $sp^3$ content of the a-D films.

• The Transactions of the Korean Institute of Electrical Engineers P
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• v.57 no.1
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• pp.22-29
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• 2008

In this paper, we propose an adaptive color enhancement algorithm. It is used for the flat panel displays (FPDs) such as LCD, PDP, and so on. The proposed algorithm consists of an adaptive linear approximation CDF(Cumulative Density Function) algorithm and an adaptive saturation enhancement algorithm. The one is for contrast enhancement which prevents an image from the distortion by luminance transient of an input image. The other is the algorithm which improves the saturation without the contour artifact and over-saturation, whose problems are generated during the enhancing saturation. In addition, it allows to achieve the high quality image using the saturation enhancement method for a preferred color of original image. Visual test and standard deviation of their histograms have been applied to evaluate the resultant output images of the proposed algorithm.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.21 no.9
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• pp.789-794
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• 2008

Zinc oxide (ZnO) has been widely studied for its practical applications such as transparent conduction electrodes for flat panel displays and solar cells. Especially, ZnO films show good chemical stability against hydrogen plasma, absence of toxicity, abundance in nature, and then suitable for photovoltaic applications. However, the fabrication process of thin film solar cells require a high substrate temperature and/or post heat treatment. Therefore, the layers have to withstand high temperatures, requiring an excellent stability without degrading their electronic and optical properties. In this paper, we investigated the stability of zinc oxide (ZnO) films doped with aluminum and hydrogen. Doped ZnO films were prepared by r.f. magnetron sputter and followed by heat treatment at different temperatures and for various times.

• Journal of the Semiconductor & Display Technology
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• v.21 no.1
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• pp.17-21
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• 2022

In the case of the manufacturing industry that produces high-tech components such as semiconductors and large flat panel displays, the manufacturing space is made into a cleanroom to increase product yield and reliability, and various environmental factors have been managed to maintain the environment. Among them, airborne particle is a representative management item enough to be the standard for actual cleanroom grade, and a sequential particle monitoring system is usually used as one parts of the FMS (Fab or Facility monitoring system). However, this method has a problem in that the measurement efficiency decreases as the length of the sampling tube increases. In this study, in order to solve this problem, a multiple regression model was created. This model can correct the measurement error due to the decrease in efficiency by sampling tube length.

• Transactions of the KSME C: Technology and Education
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• v.1 no.1
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• pp.7-12
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• 2013

Tin oxide thin-films have been widely applied in various fields of high-technology industries due to their excellent physical and electric properties. Those applications are found in various sensors, heating elements of windshield windows, solar cells, flat panel displays as tranparent electrodes. In this study, we conducted an experiment for the deposition of $SnO_2$ on glass of 2nd Gen. size for the effective development of large-scale backplanes. As deposition temperatures or flow rates of the $SnCl_4$ as a precursor changed, the thickness of tin oxide thin-films, their sheet resistances, transmittances, and hazes varied considerably.

• Korean Journal of Materials Research
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• v.24 no.8
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• pp.429-433
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• 2014

As the fabrication technology used in FPDs(flat-panel displays) advances, the size of these panels is increasing and the pattern size is decreasing to the um range. Accordingly, a cleaning process during the FPD fabrication process is becoming more important to prevent yield reductions. The purpose of this study is to develop a FPD cleaning system and a cleaning process using a two-phase flow. The FPD cleaning system consists of two parts, one being a cleaning part which includes a two-phase flow nozzle, and the other being a drying part which includes an air-knife and a halogen lamp. To evaluate the particle removal efficiency by means of two-phase flow cleaning, silica particles $1.5{\mu}m$ in size were contaminated onto a six-inch silicon wafer and a four-inch glass wafer. We conducted cleaning processes under various conditions, i.e., DI water and nitrogen gas at different pressures, using a two-phase-flow nozzle with a gap distance between the nozzle and the substrate. The drying efficiency was also tested using the air-knife with a change in the gap distance between the air-knife and the substrate to remove the DI water which remained on the substrate after the two-phase-flow cleaning process. We obtained high efficiency in terms of particle removal as well as good drying efficiency through the optimized conditions of the two-phase-flow cleaning and air-knife processes.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.30 no.3
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• pp.162-169
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• 2017

Indium tin oxide (ITO) thin films show a low sheet resistance and high transmittance in the visible range of the spectrum. Therefore, they play an important role as transparent electrodes for flat panel displays. However, their resistivity is rather high for use as a transparent electrode in large displays. One way to improve electrical and optical properties in large displays is to use ITO/Ag/ITO multilayer films. ITO/Ag/ITO multilayer films have lower sheet resistance than single layer ITO films with the same thickness. Prior to the ITO/Ag/ITO multilayer experiments, optimal condition for thickness change are necessary. Their thicknesses were deposited differently in order to analyze electrical and optical properties. However, when optimal single film characteristics are applied to ITO/Ag/ITO multilayer films, other phenomena appeared. After analyzing the electrical and optical properties by changing ITO and Ag film thickness, ITO/Ag/ITO multilayer films were optimized. By combining ITO film at $586\;{\AA}$ and Ag film at 10 nm, the ITO/Ag/ITO multilayer films showed optimized high optical transmittance of 87.65%, and the low sheet resistance of $5.5{\Omega}/sq$.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.30 no.7 s.250
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• pp.741-749
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• 2006

For last couple of decades, uses of TFI-LCDs have been expanded to many FPD(Flat Panel Display) applications including mobile displays, desktop monitors and TVs. Furthermore, there has been growing demand for increasingly larger LCD TVs. In order to meet this demand as well as to improve productivity, LCD manufactures have continued to install larger-generation display fabrication facilities which are capable of producing more panels and larger displays per mother glass(substrate). As the size of mother glass becomes larger, a robot required to handle the glass becomes bigger accordingly, and its end effectors(arms) are extended to match the glass size. With this configuration, a considerable static deflection occurs at the end of the robot arms. In order to stack maximum number of mother glasses on a given footprint, the static deflection should be compensated. This paper presents a novel static deflection compensation algorithm. This algorithm requires neither measurement instrument nor additional vertical axis on the robot. It is realized by robot controller software. The forward and inverse kinematics considering compensation always guarantees a unique solution, so the proposed algorithm can be applied to an arbitrary robot position. The algorithm reduced static deflection by 40% in stationary robot state experiment. It also improved vertical path accuracy up to 60% when the arm was running at its maximum speed. This algorithm has been commercialized and successfully applied to a seventh-generation LCD glass-handling robot.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.24 no.2
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• pp.106-112
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• 2010

In order to compete with other flat display devices such as Liquid Crystal Displays (LCDs) and organic light emitting diodes (OLEDs), Plasma Display Panels (PDPs) require to have high performances like high image quality, low power consumption and high speed driving. In this paper, Fe doped MgO protective layer was introduced for higher performance. Both the surface characteristics of the deposited thin films and the electro-optical properties of 4 inch test panels were investigated. It has been demonstrated experimentally that ac PDP with Fe doped MgO protective layer has lower discharge voltage than that of undoped MgO film, which corresponds to measured secondary electron emission coefficients. The crystallinity and surface roughness of thin films were determined by XRD patterns and AFM images. In addition, ac PDP with Fe doped MgO protective layer has improved address discharge time lag for high speed driving.

• 한국정보디스플레이학회:학술대회논문집
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• 2006.08a
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• pp.529-529
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• 2006

Several laboratories worldwide have demonstrated the feasibility of producing amorphous silicon thin film transistor (TFT) arrays at temperatures that are sufficiently low to be compatible with flexible foils such as stainless steel or high temperature polyester. These arrays can be used to fabricate flexible high information content display prototypes using a variety of different display technologies. However, several questions must be addressed before this technology can be used for the economic commercial production of displays. These include process optimization and scale-up to address intrinsic electrical instabilities exhibited by these kinds of transistor device, and the development of appropriate techniques for the handling of flexible substrate materials with large coefficients of thermal expansion. The Flexible Display Center at Arizona State University was established in 2004 as a collaboration among industry, a number of Universities, and US Government research laboratories to focus on these issues. The goal of the FDC is to investigate the manufacturing of flexible TFT technology in order to accelerate the commercialization of flexible displays. This presentation will give a brief outline of the FDC's organization and capabilities, and review the status of efforts to fabricate amorphous silicon TFT arrays on flexible foils using a low temperature process. Together with industrial partners, these arrays are being integrated with cholesteric liquid crystal panels, electrophoretic inks, or organic electroluminescent devices to make flexible display prototypes. In addition to an overview of device stability issues, the presentation will include a discussion of challenges peculiar to the use of flexible substrates. A technique has been developed for temporarily bonding flexible substrates to rigid carrier plates so that they may be processed using conventional flat panel display manufacturing equipment. In addition, custom photolithographic equipment has been developed which permits the dynamic compensation of substrate distortions which accumulate at various process steps.