• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.22 no.1
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• pp.52-59
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• 2012

Objectives: The purpose of this study was to evaluate the exposure possibility of by-products during the semiconductor manufacturing processes. Methods: The authors investigated types of chemicals generated during semiconductor manufacturing processes by the qualitative experiment on generation of by-products at the laboratory and a literature survey. Results: By-products due to decomposition of photoresist by UV-light during the photo-lithography process, ionization of arsine during the ion implant process, and inter-reactions of chemicals used at diffusion and deposition processes can be generated in wafer fabrication line. Volatile organic compounds (VOCs) such as benzene and formaldehyde can be generated during the mold process due to decomposition of epoxy molding compound and mold cleaner in semiconductor chip assembly line. Conclusions: Various types of by-products can be generated during the semiconductor manufacturing processes. Therefore, by-products carcinogen such as benzene, formaldehyde, and arsenic as well as chemical substances used during the semiconductor manufacturing processes should be controlled carefully.

• 한국정보디스플레이학회:학술대회논문집
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• 2007.08b
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• pp.1348-1351
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• 2007

We demonstrated that the threshold voltage shift owing to a gate-bias stress is originated from the trapped charges at the interface between semiconductor layer and dielectric layer, and such drawback can be settled by applying long-term delay time to the gate electrode.

• Journal of the Korean Institute of Telematics and Electronics
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• v.25 no.10
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• pp.1209-1215
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• 1988

A space charge effect at the doped silicon semiconductor/organic solvent ($C_6H_6$, $CH_3OH$, $C_2H_5OH$) interfaces and a mechanism for two reversals of zeta potentials at the undoped polycrystalline gallium arsenide semiconductor/electrolyte (NaCl, KCl, KI solution) interfaces has been qualitatively analyzed using microelectrophoresis measurements. It has been found that the space charge effect in the organic solvents can be neglected and the two reversals of zeta potentials depend on surface states, specific adsorption, electronegativity and size of specifically adsorbed ions at the undoped polycrystalline gallium arsenide/electrolyte interfaces. The position of shear plane of colloidal semiconductors is a fixed distance from the surface and is almost or exactly coincides with the outer Helmholtz plane (OHP).

• 한국정보디스플레이학회:학술대회논문집
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• 2007.08a
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• pp.62-65
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• 2007

Conventional semiconductor processes have been utilized to fabricate 3.5-inch OTFT-driven OLEDs with a resolution of $176\;{\times}\;144$ pixels on plastic substrates. By using a PC-OVD method to deposit a pentacene layer and optimizing patterning and the following processes, we could complete a uniform and reliable integration procedure for an active matrix organic light emitting devices on a plastic substrate. The technical importance of ours is the applicability of conventional semiconductor process to organic materials on plastic substrates. Although there are many hurdles to overcome, our approach and technical improvements are proved to be applicable to plastic electronics.

• Journal of the Semiconductor & Display Technology
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• v.23 no.2
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• pp.82-86
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• 2024

With the growing field and growing interest in transparent organic light-emitting diodes (TOLED) in the industry, various attempts are being made to improve the transmittance and performance of TOLED. TOLEDs are expected to be used in next-generation displays such as mixture reality (MR) displays, displayable windows, televisions, etc. This study presents a mesh TOLED with better transmittance and luminescence characteristics than existing TOLEDs through an in-situ vacuum deposition method that does not require additional processes such as photolithography and etching. In this study the mesh TOLED's cathode consists of Mg: Ag 1:9 electrode. Mesh patterns are interconnected with a 6 nm layer of interlayer. We approached transmittance improvement up to 30% at 555 nm at the cathode electrode with similar current injection character, also we improved lumination characteristics up to 23% at 7 V driving condition.

• Journal of the Semiconductor & Display Technology
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• v.4 no.2 s.11
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• pp.1-5
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• 2005

Electon spin resonance measurements have been performed on the Mg-doped wurtzite GaN thin films grown on sapphire substrates by low-pressure metal-organic chemical vapor deposition. The sample set included films as-grown with the regular Mg doped and Mg delta doped samples and the corresponding annealed ones. The resonance signal has been observed from the annealed Mg delta-doped sample with the Lande g value of 2.029. This indicates that the singlet resonance signal originates from the neutral Mg acceptor located at 0.24 eV above the valence band edge and 0.13 eV above the Fermi level because of the nuclear hyperfine spin 1=0 of Mg and the larger value than the free electron g=2.0023.

• Journal of the Semiconductor & Display Technology
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• v.16 no.2
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• pp.19-26
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• 2017

The cure properties of ethoxysilyl bisphenol A type epoxy resin (Ethoxysilyl-DGEBA) systems with different hardeners were investigated, comparing with DGEBA and Diallyl-DGEBA epoxy resin systems. The cure kinetics of these systems were analyzed by differential scanning calorimetry with an isothermal approach, and the kinetic parameters of all systems were reported in generalized kinetic equations with diffusion effects. The Ethoxysilyl-DGEBA epoxy resin system showed lower cure conversion rates than DGEBA and Diallyl-DGEBA epoxy resin systems. The conversion rates of these epoxy resin systems with DDM hardener are lower than those with HF-1M hardener. It can be considered that the optimum hardener for Ethoxysilyl-DGEBA epoxy resin system is Phenol Novolac type. These lower cure conversion rates in the Ethoxysilyl-DGEBA epoxy resin systems could be explained by the retardation of reaction molecule movements according to the formation of organic-inorganic hybrid network structure by epoxy and ethoxysilyl group in Ethoxysilyl- DGEBA epoxy resin system.

• Proceedings of the Korean Society Of Semiconductor Equipment Technology
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• 2007.06a
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• pp.164-168
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• 2007

Deformation of a shadow mask is one of the problems encountered during the deposition of organic materials for manufacturing large size OLED. The larger the glass substrate, the larger the shadow mask becomes. But as the size of the shadow mask increases, its deformation becomes more severe, thereby making it difficult to deposit organic materials in a precise pattern on a substrate. In this paper, a new type mask-frame structure is proposed. The proposed mask-frame structure making a curved mask has the ability of reducing drooping of mask. The test frame is fabricated and evaluation experiments are performed.

• Journal of Information Display
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• v.9 no.2
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• pp.1-4
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• 2008

In this study, we investigate the capacitance-voltage (C-V) characteristics of metal-insulator-semiconductor (MIS) capacitors consisting of pentacene, as an organic semiconductor, and polymeric insulators such as poly(4-vinylphenol) (PVP) orpolystyrene (PS) prepared by spin-coating process, to analyze the interfacial characteristics between pentacene and polymeric insulators. Compared with the device with PS, the MIS capacitor with PVP exhibited a pronounced shift in the flat-band voltage according to the bias sweep direction. This hysteric feature in the C-V characteristics is thought to be attributed to the trapped charges at the interface between pentacene and PVP owing to the hydrophilicity of PVP. From the experimental results, we can conclude that surface polarity of polymeric insulator has a critical effect on the interfacial properties, thereby affecting the bias stability of organic thin-film transistors.

• 한국정보디스플레이학회:학술대회논문집
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• 2005.07b
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• pp.1413-1415
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• 2005

The OTFT performance depends strongly on the interfacial properties between an organic semiconductor and ${\alpha}$ metal electrode. The contact resistance is critical to the current flow in the device. The contact resistance arises mainly from the Schottky barrier formation due to the work function difference between the semiconductor and electrodes. We doped pentacene/source-drain interfaces with $F_4TCNQ$ (2,3,5,6-Tetrafluoro-7,7,8,8-tetracyanoquinodimethane), resulting in p-doped region at the SD contacts, in order to solve this problem. We found that the mobility increased and the threshold voltage decreased.