• Ceramist
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• v.23 no.2
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• pp.178-183
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• 2020

Solar energy conversion is now actively researching because of pollution. Especially silicon photocatalyst has big potential, because of wide absorption range. But low quantum yield of silicon photocatalyst can't be used for commercialization. This paper summarize mechanism of silicon photocatalyst. In addition, properties and current states of photo catalyst using nanomaterials of silicon are also introduced.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2001.11a
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• pp.255-257
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• 2001

In this paper, the silicon rubber insulator for transmission line was experimented for 1,000 hours aging test in salt-fog condition. To evaluate and examine the aging properties of silicon rubber insulator for test, the leakage current of surface was measured. Also hydrophobicity and scanning electron microscopy were compared with initial and aged sample respectively Above results, we can confirm that the surface properties of silicon rubber insulator easily aged by salt-fog condition.

• 한국신재생에너지학회:학술대회논문집
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• 2010.06a
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• pp.90.2-90.2
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• 2010

The crystalline silicon solar cells have been optical losses. but it can be reduced using light trapping by texture structure and anti-reflection coating. The high reflective index of crystalline silicon at solar wavelengths(400nm~1000nm) creates large reflection losses that must be compensated for by applying anti-reflection coating. In this study, the use of porous silicon(PSi) as an active material in a solar cell to take advantage of light trapping and blue-harvesting photoluminescence effect. Porous silicon is form by anodization and can be obtained in an electrolyte with hydrofluoric. We expect our research can results approaching to lower than 10% of several reflectance by porous silicon solar cells.

• Journal of the Korean Ceramic Society
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• v.22 no.1
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• pp.53-59
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• 1985

Experiments related to nitriding silicon with addition of $Si_3N_4$ have provided information on the effects of such inclusion on the phase relationships of Reaction Bonded Silicon Nitride. In the current work specimens containing 0-25wt% Si3N4 which have 55.5wt% $\alpha$ 4.5wt% $eta$, 40wt% amorphous phase were nitrided for 7-20 hours at 1300-135$0^{\circ}C$ The evaluation of nitridation was per-formed by means of $\alpha$-and $\beta$-phase contents determination in nitrided specimens, In order to observe nitrided region between silicon and silicon nitride scanning electron microscopy was used to study reacted region between silicon and silicon nitride particle. For this purpose semiconductor-grade silicon wafer single crystal was used as a silicon source. The incorporation of small amount of $Si_3N_4$ powder is contributed to enhancing the rate of formation of $\alpha$-phase.

• Journal of the Korean Society of Manufacturing Technology Engineers
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• v.6 no.4
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• pp.34-38
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• 1997

This paper presents a joining method by using the silicon wafer in order to apply to joint to the 3-dimensional structures of semiconductor device, high-speed , high integration, micro machine, silicon integrated sensor, and actuator. In this study, the high atomic beam, stabilized by oxidation film and organic materials at the material surface, is investigated, and the purified is obtained by removing the oxidation film and pollution layer at the materials. And the unstable surface is obtained, which can be easily joined. In order to use the low temperatures for the joint method, the main subjects are obtained as follows: 1) In the case of the silicon wafer and the silicon wafer and the silicon wafer of alumina sputter film, the specimens can be jointed at 2$0^{\circ}C$, and the joining strength is 5Mpa. 2) The specimens can not always be joined at the room temperatures in the case of the silicon wafer and the silicon wafer of alumina sputter film.

• 연구논문집
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• s.34
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• pp.131-138
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• 2004

Porous silicon nitride ceramics were prepared by Self-propagating High Temperature Synthesis from silicon powder, silicon nitride powder and the pore-forming precursor. The microstructure, porosity and the flexural strength of the porous silicon nitride ceramics were varied according to the Si/$Si_3N_4$ ratio, size and amount of the pore-forming precursors. Some samples exhibited as high flexural strength as $162\pm24$ MPa. The high strength is considered to result from the fine pore size and the strong bonding among the silicon nitrid particles.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2001.07a
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• pp.874-877
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• 2001

SOI(Silicon-On-Insulator) technology is proposed as an alternative to bulk silicon for MEMS(Micro Electro Mechanical System) manufacturing. In this paper, we fabricated the SOI wafer with uniform active layer thickness by silicon direct bonding and mechanical polishing processes. Specially-designed electrostatic bonding system is introduced which is available for vacuum packaging and silicon-glass wafer bonding for SOG(Silicon On Glass) wafer. We demonstrated thermopile sensor and RF resonator using the SOI wafer, which has the merits of simple process and uniform membrane fabrication.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.19 no.4
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• pp.334-338
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• 2006

Poly silicon TFT requires high quality dielectric film; conventional method of growing silicon dioxide needs highly hazardous chemicals such as silane. We have grown high quality dielectric film of silicon dioxide using non-hazardous chemical such as TFOS and ozone as reaction gases by APCVD. The films grown were characterized through C-V curves of MOS structures. Conventional APCVD requires high temperature processing where as in the process of current study, we developed a low temperature process. Interface trap density was substantially decreased in the silicon surface coated with the silicon dioxide film after annealing in nitrogen ambient. The interface with such low trap density could be used for poly silicon TFT fabrication with cheaper cost and potentially less hazards.

• Journal of the Microelectronics and Packaging Society
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• v.10 no.3
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• pp.67-71
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• 2003

Sawing silicon ingot with abrasive slurry generates sludge that includes abrasive powders, cutting oil, and silicon powders. The abrasive powders and cutting oil are being separated and reused. Mixing the remained stodged silicon powders with carbon powders and subsequent heat-treatment are conducted to produce silicon carbide. The size of SiC whiskers and powders was smaller than the conventionally grown silicon carbide whiskers that were synthesized by adding micron-size metal impurities. Impurity related mechanism is attributed to the formation of the silicon carbide whiskers, as metal impurities are contained in the stodged silicon powders.

• Proceedings of the Korean Powder Metallurgy Institute Conference
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• 2006.09b
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• pp.1091-1092
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• 2006

Silicon nitride - silicon carbide composite was developed by using an abrasive SiC powders as a raw material. The composites were prepared by mixing abrasive SiC powder with silicon, pressing and sintering at $1400^{\circ}C$ under nitrogen atmosphere in atmosphere controlled vacuum furnace. The proportion of silicon in the initial mixtures varied from 20 to 50 wt%. After sintering, crystalline phases and microstructure were characterized. All composites consisted of ${\alpha}-Si_3N_4$ and ${\beta}-Si_3N_4$ as the bonding phases in SiC matrix. Their physical and mechanical properties were also determined. It was found that the density of the obtained composites increased with an increase in the $Si_3N_4$ content formed in the reaction.