• Korean Journal of Materials Research
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• v.5 no.6
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• pp.732-742
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• 1995

Effects of the substrate pretreatment on uncleation density of the diamond thin films have been investigated. The film was prepared using the hot-filament CVD reactor with the mixture of methane and hydrogen. The substrate pretreatment was done in three different ways: predeposition of carbon on the substrate, soot on the substrate, and graphite on the substrate. All three cases enhanced the nucleation density of diamond. And the effect was more marked in the first and the second cases than in the third one. In the first case where the substrate was predeposited by the carbon phase, a very smooth and uniform film of diamond could be obtained. Since the bound strength between the substrate and the predeposited carbon phase is relatively weak, separation of the diamond film layer from the substrate was found to be easy.

• Proceedings of the Korean Vacuum Society Conference
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• 2013.08a
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• pp.237.2-237.2
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• 2013

ReRAM cell, also known as conductive bridging RAM (CBRAM), is a resistive switching memory based on non-volatile formation and dissolution of conductive filament in a solid electrolyte [1,2]. Especially, Chalcogenide-based ReRAM have become a promising candidate due to the simple structure, high density and low power operation than other types of ReRAM but the uniformity of switching parameter is undesirable. It is because diffusion of ions from anode to cathode in solid electrolyte layer is random [3]. That is to say, the formation of conductive filament is not go through the same paths in each switching cycle which is one of the major obstacles for performance improvement of ReRAM devices. Therefore, to control of nonuniform conductive filament formation is a key point to achieve a high performance ReRAM. In this paper, we demonstrated the enhanced repeatable bipolar resistive switching memory characteristics by spreading the Ag nanocrystals (Ag NCs) on amorphous GeSe layer compared to the conventional Ag/GeSe/Pt structure without Ag NCs. The Ag NCs and Ag top electrode act as a metal supply source of our devices. Excellent resistive switching memory characteristics were obtained and improvement of voltage distribution was achieved from the Al/Ag NCs/GeSe/Pt structure. At the same time, a stable DC endurance (>100 cycles) and an excellent data retention (>104 sec) properties was found from the Al/Ag NCs/GeSe/ Pt structured ReRAMs.

• Aerospace Engineering and Technology
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• v.2 no.2
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• pp.124-132
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• 2003

This paper described the structural design and the fabrication procedure of KSR-III composite pressure tank. The type of the composite pressure tank was COPV(Composite Overwrapped Pressure Vessel). A non-load sharing liner was made of aluminum 6061-0 and the liner provided a helium gas seal. The composite pressure tank was winded using T700 carbon/epoxy on the liner. Because the aluminum liner was thin, multiple cure cycles were applied to the filament winding technique. The multiple cure cycles prevented the liner-cylinder from losing a circular shape. A fitting force at the metallic boss was spread to the carbon fiber by a boss ring. The boss ring also prevented a local deformation at the boss part.

• Korean Journal of Materials Research
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• v.13 no.1
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• pp.31-35
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• 2003

The intensity is measured as functions of both distance from filament to substrate and $CH_3$OH/($CH_3$OH＋$H_2$O) ratio by OES(Optical Emission Spectroscopy) to investigate the effects of activation species such as $H_{\alpha}$, $H_{\beta}$, H$\Upsilon\;C_3$, CH on diamond film growth.$ H_{\alpha}$ increases as $CH_3$OH composition decreases, while CH increases as $CH_3$OH composition increases. The intensity of $H_{\alpha}$ decreases as the distance increases and that of CH increases as the distance increases. The intensities of other activation species of $H_{\beta}$, H$\Upsilon\;C_3$, do not vary as a function of measured position distance. It varies randomly. It means that various parameters for depositing diamond thin film can be explained by the intensity(density) change of activation species, as a function of the distance of the filament.

• ALGAE
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• v.21 no.2
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• pp.209-216
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• 2006

The characteristics of Peyssonnelia capensis Montagne (Peyssonneliaceae, Rhodophyta) from Jeju Island were investigated in order to clarify the species entity and re-evaluate taxonomic position. The morphological variations of the Peyssonnelia capensis from Jeju Island were divided into two types, the thin thallus type and the thick thallus type. The thin thallus type is characterized by thin, soft, orbicular, slightly lobed thallus with entire to undulate margin, and compact rhizoids. The thick thallus type has thick and stiff thallus with sinuate margin and scattered rhizoids, and has more branches than the thin thallus type. The basal layer and the epithallium of thin thallus type are similar to those of thick thallus types in their structure. However, the hypothallial cells of the thick thallus type are longer than those of the thin thallus type. The erect filament of thick thallus type has more cells than those of the thin thallus type. Tetrasporangial nemathecia are distinctly protruded. Mature tetrasporangia of this species are divided cruciately into four spores as those of other Peyssonneliaceae. In addition to their morphological and anatomical distinctness between two types, the nucleotide sequence analyses of SSU and ITS2 region make no differences among populations from Jeju and other localities in Korea. Therefore these two morphological variation may not base on genetic variation.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.29 no.7
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• pp.400-403
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• 2016

The resistive memory switching characteristics of resistive random access memory (ReRAM) using the amorphous GeSe thin film have been demonstrated at Al/Ti/GeSe/$n^+$ poly Si structure. This ReRAM indicated bipolar resistive memory switching characteristics. The generation and the recombination of chalcogen cations and anions were suitable to explain the bipolar switching operation. Space charge limited current (SCLC) model and Poole-Frenkel emission is applied to explain the formation of conductive filament in the amorphous GeSe thin film. The results showed characteristics of stable switching and excellent reliability. Through the annealing condition of $400^{\circ}C$, the possibility of low temperature process was established. Very low operation current level (set current: ~ ${\mu}A$, reset current: ~ nA) was showed the possibility of low power consumption. Particularly, $n^+$ poly Si based GeSe ReRAM could be applied directly to thin film transistor (TFT).

• Proceedings of the Korean Vacuum Society Conference
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• 2012.08a
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• pp.343-344
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• 2012

It has been known since the mid 1960s that Ag can be photodissolved in chalcogenide glasses to form materials with interesting technological properties. In the 40 years since, this effect has been used in diverse applications such as the fabrication of relief images in optical elements, micro photolithographic schemes, and for direct imaging by photoinduced Ag surface deposition. ReRAM, also known as conductive bridging RAM (CBRAM), is a resistive switching memory based on non-volatile formation and dissolution of a conductive filament in a solid electrolyte. Especially, Ag-doped chalcogenide glasses and thin films have become attractive materials for fundamental research of their structure, properties, and preparation. Ag-doped chalcogenide glasses have been used in the formation of solid electrolyte which is the active medium in ReRAM devices. In this paper, we investigated the nature of thin films formed by the photo-dissolution of Ag into Ge-Se glasses for use in ReRAM devices. These devices rely on ion transport in the film so produced to create electrically programmable resistance states. [1-3] We have demonstrated functionalities of Ag doped chalcogenide glasses based on their capabilities as solid electrolytes. Formation of such amorphous systems by the introduction of Ag+ ions photo-induced diffusion in thin chalcogenide films is considered. The influence of Ag+ ions is regarded in terms of diffusion kinetics and Ag saturation is related to the composition of the hosting material. Saturated Ag+ ions have been used in the formation of conductive filaments at the solid electrolyte which is the active medium in ReRAM devices. Following fabrication, the cell displays a metal-insulator-metal structure. We measured the I-V characteristics of a cell, similar results were obtained with different via sizes, due to the filamentary nature of resistance switching in ReRAM cell. As the voltage is swept from 0 V to a positive top electrode voltage, the device switches from a high resistive to a low resistive, or set. The low conducting, or reset, state can be restored by means of a negative voltage sweep where the switch-off of the device usually occurs.

• Proceedings of the Korean Vacuum Society Conference
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• 2014.02a
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• pp.326-326
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• 2014

It has been known since the mid 1960s that Ag can be photodissolved in chalcogenide glasses to form materials with interesting technological properties. In the 40 years since, this effect has been used in diverse applications such as the fabrication of relief images in optical elements, micro photolithographic schemes, and for direct imaging by photoinduced Ag surface deposition. ReRAM, also known as conductive bridging RAM (CBRAM), is a resistive switching memory based on non-volatile formation and dissolution of a conductive filament in a solid electrolyte. Especially, Ag-doped chalcogenide glasses and thin films have become attractive materials for fundamental research of their structure, properties, and preparation. Ag-doped chalcogenide glasses have been used in the formation of solid electrolyte which is the active medium in ReRAM devices. In this paper, we investigated the nature of thin films formed by the photo-dissolution of Ag into Ge-Se glasses for use in ReRAM devices. These devices rely on ion transport in the film so produced to create electrically programmable resistance states [1-3]. We have demonstrated functionalities of Ag doped chalcogenide glasses based on their capabilities as solid electrolytes. Formation of such amorphous systems by the introduction of Ag+ ions photo-induced diffusion in thin chalcogenide films is considered. The influence of Ag+ ions is regarded in terms of diffusion kinetics and Ag saturation is related to the composition of the hosting material. Saturated Ag+ ions have been used in the formation of conductive filaments at the solid electrolyte which is the active medium in ReRAM devices. Following fabrication, the cell displays a metal-insulator-metal structure. We measured the I-V characteristics of a cell, similar results were obtained with different via sizes, due to the filamentary nature of resistance switching in ReRAM cell. As the voltage is swept from 0 V to a positive top electrode voltage, the device switches from a high resistive to a low resistive, or set. The low conducting, or reset, state can be restored by means of a negative voltage sweep where the switch-off of the device usually occurs.

• Applied Microscopy
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• v.17 no.2
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• pp.31-40
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• 1987

The tentacular retractor muscle has many arrays of muscle fiber bundles under the epithelial layer. Most of muscle fiber bundles are arranged in parallel to the longitudinal axes of muscle fibers and a small number of them perpendiculary to them. These smooth muscle cells are filled with compactly arranged myosins and actins. These microfilaments, when the tentacle is protracted, keep abreast with straight for-ward-lined shapes while these microfilaments, when it is retracted, with curved shapes. The foldings in the sarcolemma of the muscle cell, when the tentacle is retracted, lead to the formation of normal subsurface tubules along with which a few mitochondria are included. It is thought that the formation of the sarcolemmal differentiation like the subsurface tubules has a close relation with the protraction and retraction of the tentacle. Mitochondria are found throughout the muscle cell, and sarcoplasmic reticulum (SR) developed greatly in the exoplasm close to the sarcolemma and associated with the cell membrane. Dense bodies are distributed irregularly and thin filaments are scattered around the thick filament in cross-sections, but the thin filaments may be arranged in complete or partial orbits around thick filaments. Complete orbits are infrequent.

• Biomedical Science Letters
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• v.7 no.2
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• pp.59-64
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• 2001

Nebulin is an unusually large actin-binding protein specific to the skeletal muscle of vertebrates. The correlation of nebulin size with thin filament length have led to the suggestion that nebulin acts as a molecular ruler for the length of thin filaments. An SH3 domain occupies the C terminus of nebulin, in the sarcomeric Z-disk and is preceded by a 120-residue stretch containing multiple putative phosphorylation sites. SH3 domain mediates protein-protein interaction involved in the subcellular localization of proteins, cytoskeletal organization and signal transduction. However the binding partner and physiological role of nebulin SH3 domains remains unknown. Using the yeast two-hybrid system, we identified supervillin, an actin-binding protein, as a nebulin SH3 domain-interacting protein. The SH3 domain of nebulin binds to the sequence encoding amino acids 977 to 1335 of supervillin. But the sequence encoding amino acids 977 to 1335 displays weaker binding than the sequence encoding amino acids 977 to 1788.