• KSBB Journal
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• 제20권1호
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• pp.50-54
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• 2005

셀룰로오스의 탄화과정에서는 셀룰로오스의 pyrolysis에 의 해 생산된 타르에 의해 탄화 후, 셀룰로오스 탄화물의 섬유구조를 저해시키는 문제점이 존재한다. 이와 같은 결과는 $800^{\circ}C$이상의 탄화온도와 건조 셀룰로오스를 toluene에 침지하고 초음파 처리 후 탄화한 탄화물에서 감소되지만, 섬유구조만의 탄화물을 얻을 수 없었다. 그러나 셀룰로오스의 탄화에서 타르의 생산을 감소시키는 HCI vapor flow 조건에서의 열처리 과정의 적용과 탄화과정 중 생성된 타르의 제거를 통해서 탄화 후, 대부분의 영역에서 섬유 구조를 갖는 탄화물을 얻을 수 있었다.

• 한국재료학회지
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• 제26권8호
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• pp.427-429
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• 2016

A multi-step deposition process for the gap-filling of submicrometer trenches using dimethyldimethoxysilane (DMDMOS), $(CH_3)_2Si(OCH_3)_2$, and $C_xH_yO_z$ by plasma enhanced chemical vapor deposition (PECVD) is presented. The multi-step process consisted of pre-treatment, deposition, and post-treatment in each deposition step. We obtained low-k films with superior gap-filling properties on the trench patterns without voids or delamination. The newly developed technique for the gap-filling of submicrometer features will have a great impact on inter metal dielectric (IMD) and shallow trench isolation (STI) processes for the next generation of microelectronic devices. Moreover, this bottom up gap-fill mode is expected to be universally for other chemical vapor deposition systems.

• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2005년도 International Meeting on Information Displayvol.II
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• pp.1096-1099
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• 2005

Multi-walled carbon nanotubes (CNTs) grown on catalyst dots by thermal chemical vapor deposition were vertically aligned with a high population density. Such densely populated CNTs showed poor field emission characteristics due to the electrical screening effect. We reduced the number density of CNTs using an adhesive tape treatment. For dotpatterned CNTs, the tape treatment decreased the CNT density by three orders of magnitude, drastically improved the turn-on electric field from 4.8 to $1.8V/{\mu}m$, and changed the emission image from spotty to uniform luminescence. We also report long-term emission stability of dot-patterned CNTs by measuring the emission currents with time at different duty ratios.

• 열처리공학회지
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• 제3권1호
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• pp.1-7
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• 1990

To investigate the influence of r.f. power and electrode distance on the TiN deposition, TiN films were deposited onto STC3, STD11 steel and Si-wafer from gas mixtures of $TiC_4/N_2/H_2$ using the radio frequency plasma assisted chemical vapor deposition. The crystallinity of TiN film could be improved by the increase of r.f. power and the decrease of electrode distance. The TiN coated layer contains chlorine, its content were decreased with increasing r.f. power as well as decreasing electrode distance. And the thickness of deposited TiN was largely affected by r.f. power and electrode distance. The hardness of deposited TiN reached a maximum value of about Hv 2,000.

• Applied Science and Convergence Technology
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• 제24권6호
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• pp.268-272
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• 2015

We report the systematic study to reduce extrinsic doping in graphene grown by chemical vapor deposition (CVD). To investigate the effect of crystallinity of graphene on the extent of the extrinsic doping, graphene samples with different levels of crystal quality: poly-crystalline and single-crystalline graphene (PCG and SCG), are employed. The graphene suspended in air is almost undoped regardless of its crystallinity, whereas graphene placed on an $SiO_2/Si$ substrate is spontaneously p-doped. The extent of p-doping from the $SiO_2$ substrate in SCG is slightly lower than that in PCG, implying that the defects in graphene play roles in charge transfer. However, after annealing treatment, both PCG and SCG are heavily p-doped due to increased interaction with the underlying substrate. Extrinsic doping dramatically decreases after annealing treatment when PCG and SCG are placed on the top of hexagonal boron nitride (h-BN) substrate, confirming that h-BN is the ideal substrate for reducing extrinsic doping in CVD graphene.

• Journal of Applied Biological Chemistry
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• 제43권2호
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• pp.79-85
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• 2000

Biodegradable films were prepared from roasted sesame meal and rice bran. Acetic anhydride, succinic anhydride, and formaldehyde were added to the film-forming solutions, and their effects on tensile strength, percent elongation, water vapor permeability, and water solubility of the films were studied. Roasted sesame meal did not form film without acylation or addition of formaldehyde. Acylated roasted sesame films had higher tensile strength and water-solubility, and lower % elongation than rice bran films. Acylation with acetic and succinic anhydrides increased tensile strength, percent elongation, and water solubility of rice bran films, but decreased water vapor permeability. Treatment with formaldehyde increased tensile strength of roasted sesame and rice bran films and % elongation of rice bran films, while reducing water-solubility of roasted sesame and rice bran films and water vapor permeability of rice bran films.

• Bulletin of the Korean Chemical Society
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• 제27권2호
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• pp.169-184
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• 2006

A review is made on the chemical vapor deposition polymerization (CVDP) of insoluble and infusible poly(arylenevinylene)s and its applications to nanoscience. Poly(p-phenylenevinylene) (PPV), poly(naphthylenevinylene)s, poly(2,5-thinenylenevinylene) (PTV), and other homologous polymers containing oligothiophenes could be prepared by the CVDP method in the form of films, tubes, and fibers of nano dimensions. They would be readily converted to graphitic carbons of different structures by thermal treatment. Field emission FE) of carbonized PPV nanotubes, photoconductivity of carbonized PPV/PPV bilayer nanotubes and nanofilms also were studied.

• 한국전기전자재료학회논문지
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• 제11권5호
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• pp.340-346
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• 1998

In this study, we intended to investigate aging effect of polyimide prepared by VDPD(vapor deposition polymerized method). The prepared polymide was treated by the oxygen and argon gas plasma. And we evaluated the polyimide treated by plasma from contact angle, surface leakage current, FT-IR and SEM. We know that the structure of polyimide at surface are changed to amide structure by plasma treating. It seems that strong energy of plasma causes breaking the molecular chin of the polyimide. And surface roughness increases with plasma treating time increased and sequentially the wettability and leakage current increases.

• 한국표면공학회지
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• 제56권6호
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• pp.341-352
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• 2023

This paper reviews the potentials of a rotary chemical vapor deposition (RCVD) process for nanomaterial synthesis and coating on powder-based materials. The rotary reactor offers a significant improvement over traditional CVD methods having horizontal and fixed reaction chambers. The RCVD system yields enhanced productivity and surface coating uniformity of nanoparticles applied in various purposes, such as efficient heat dissipation, surface hardness enhancement, and enhanced energy storage performances. The effectiveness of the RCVD system would open up new possibilities in various applications because uniform coating on powder-based materials with massive productivity is inevitable to develop multi-functional materials with high reliability.

• 한국진공학회:학술대회논문집
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• 한국진공학회 2001년도 창립10주년 제20회 학술발표회
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• pp.107-107
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• 2001