• 한국추진공학회:학술대회논문집
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• 한국추진공학회 2012년도 제38회 춘계학술대회논문집
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• pp.424-428
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• 2012

공기흡입형 추진기관은 운용의 단순함, 저비용, 저장의 용이성 등의 장점으로 각광받고 있는 추진 기관이다. 본 논문에서는 Boron을 이용한 공기흡입형 추진기관의 가스발생기에 사용될 추진제 연구를 수행하였다. 이를 위하여, Amorphous Boron Powder를 적용한 추진제에 다양한 첨가제를 사용하여 연소특성을 파악하였고, Boron bead를 제조하여 추진제에 적용하여 Amorphous Boron Power를 적용한 추진제와의 차이점을 비교 분석 하였다.

• Journal of Magnetics
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• 제3권3호
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• pp.78-81
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• 1998

Large magneto crystalline anisotropy energy and demagnetization energy of rare earth-transition metal (RF-TM) alloys play roles of bottlenecks towards their commercial applications for giant magnetostrictive and blue wavelength magneto optical recording materials, respectively. To solve the above problems, boron is added into amorphous RE-TM alloys to produce its electron transferring. The boron added amorphous RE-TM alloys show novel magnetic and magneto-optical properties as follows; 1) an amorphous $(Sm_{33}Fe_{76})$97B3 alloy obtains the magnetostriction of$ -550{times}10^{-6}$ at 400 Oe compared with saturation magnetostriction of$ -60{\times}10^{-6}$ in conventional Ni based alloys, 2) an amorphous$ (Nd_{33}Fe_{67})_{95}B_5$ alloy increases effective magnetic anisotropy to$ -0.5{\times}10^{-6} ergs/cm^3 from -3.5{\times}10^6 ergs/cm^3$ without boron, which correspond to the polar Kerr rotation angles of 0.52$^{\circ}$and 0.33$^{\circ}$, respectively. These results attribute to selective 2p-3d electron orbits exchange coupling (SEC).

• 한국건축시공학회지
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• 제17권1호
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• pp.9-14
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• 2017

본 연구에서 비정질 붕소강 섬유를 혼입한 콘크리트의 역학적 성능 및 중성자 차폐성능을 평가하였다. 비정질 붕소강 섬유를 콘크리트 체적 대비 0.25%에서 1.0%까지 혼입하여 굳지 않은 콘크리트의 공기량과 슬럼프값, 경화된 콘크리트의 압축강도, 휨강도, 휨인성 및 중성자 차폐성능을 평가하였다. 실험결과, 비정질 붕소강 섬유의 혼입량이 증가할수록 콘크리트의 휨인성 및 중성자 차폐성능이 향상되는 것으로 나타났다. 이를 통해 비정질 붕소강 섬유의 혼입이 중성자 차폐성능 뿐만 아니라 역학적 성능을 효과적으로 개선시켜 줄 것이라고 기대된다.

• 한국건설순환자원학회논문집
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• 제4권3호
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• pp.269-275
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• 2016

본 연구에서는 붕규산 유리와 비정질 붕소강 섬유를 혼입한 콘크리트의 역학적 성능 및 중성자 차폐성능을 평가하였다. 잔골재를 붕규산 유리로 치환한 콘크리트와 비정질 붕소강 섬유를 보강한 콘크리트를 제조하여 압축강도, 정탄성계수, 압축인성, 휨강도, 휨인성, 중성자 차폐성능을 평가하였다. 실험결과, Plain 콘크리트와 대비하여 붕규산 유리를 혼입한 콘크리트의 경우 압축강도 및 휨강도는 저하되었으나, 중성자 차폐성능은 향상되는 것으로 나타났다. 비정질 붕소강 섬유를 혼입한 콘크리트의 경우 Plain 콘크리트와 대비하여 압축인성 및 휨인성이 증진되었으며 중성자 차폐성능도 향상되는 것으로 나타났다.

• 한국재료학회지
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• 제25권12호
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• pp.659-665
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• 2015

The self-propagating high temperature synthesis approach was applied to synthesize amorphous boron nano-powders in argon atmospheres. For this purpose, we investigated the characteristics of a thermally induced combustion wave in the $B_2O_3+{\alpha}Mg$ system(${\alpha}=1.0-8.0$) in an argon atmospheres. In this study, the exothermic nature of the $B_2O_3-Mg$ reaction was investigated using thermodynamic calculations. Experimental study was conducted based on the calculation data and the SHS products consisting of crystalline boron and other compounds were obtained starting with a different initial molar ratio of Mg. It was found that the $B_2O_3$ and Mg reaction system produced a high combustion temperature with a rapid combustion reaction. In order to regulate the combustion reaction, NaCl, $Na_2B_4O_7$ and $H_3BO_3$ additives were investigated as diluents. In an experimental study, it was found that all diluents effectively stabilized the reaction regime. The final product of the $B_2O_3+{\alpha}Mg$ system with 0.5 mole $Na_2B_4O_7$ was identified to be amorphous boron nano-powders(< 100 nm).

• 한국주조공학회지
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• 제31권5호
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• pp.267-273
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• 2011

Erosion and thermal shock resistance of several refractory materials have been investigated, which are expected to be used as nozzles in a planar flow casting equipment for amorphous alloys. The test was conducted on five materials; graphite, boron nitride, fused silica, alumina and zirconia. Test specimens were preheated and dipped into the melt of carbon steel and amorphous alloys. Some test specimens were rotated to develop high erosion and to shorten the test periods. Fused silica and boron nitride specimens showed the excellent erosion and thermal shock resistance irrespective of the kind of melt and melting atmosphere.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2009년도 하계학술대회 논문집
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• pp.456-456
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• 2009

Boron doping on an n-type Si wafer is requisite process for IBC (Interdigitated Back Contact) solar cells. Fiber laser annealing is one of boron doping methods. For the boron doping, uniformly coated or deposited film is highly required. Plasma enhanced chemical vapor deposition (PECVD) method provides a uniform dopant film or layer which can facilitate doping. Because amorphous silicon layer absorption range for the wavelength of fiber laser does not match well for the direct annealing. In this study, to enhance thermal affection on the existing p-a-Si:H layer, a ${\mu}c$-Si:H intrinsic layer was deposited on the p-a-Si:H layer additionally by PECVD. To improve heat transfer rate to the amorphous silicon layer, and as heating both sides and protecting boron eliminating from the amorphous silicon layer. For p-a-Si:H layer with the ratio of $SiH_4$ : $B_2H_6$ : $H_2$ = 30 : 30 : 120, at $200^{\circ}C$, 50 W, 0.2 Torr for 30 minutes, and for ${\mu}c$-Si:H intrinsic layer, $SiH_4$ : $H_2$ = 10 : 300, at $200^{\circ}C$, 30 W, 0.5 Torr for 60 minutes, 2 cm $\times$ 2 cm size wafers were used. In consequence of comparing the results of lifetime measurement and sheet resistance relation, the laser condition set of 20 ~ 27 % of power, 150 ~ 160 kHz, 20 ~ 50 mm/s of marking speed, and $10\;{\sim}\;50 {\mu}m$ spacing with continuous wave mode of scanner lens showed the correlation between lifetime and sheet resistance as $100\;{\Omega}/sq$ and $11.8\;{\mu}s$ vs. $17\;{\Omega}/sq$ and $8.2\;{\mu}s$. Comparing to the singly deposited p-a-Si:H layer case, the additional ${\mu}c$-Si:H layer for doping resulted in no trade-offs, but showed slight improvement of both lifetime and sheet resistance, however sheet resistance might be confined by the additional intrinsic layer. This might come from the ineffective crystallization of amorphous silicon layer. For the additional layer case, lifetime and sheet resistance were measured as $84.8\;{\Omega}/sq$ and $11.09\;{\mu}s$ vs. $79.8\;{\Omega}/sq$ and $11.93\;{\mu}s$. The co-existence of $n^+$layeronthesamesurfaceandeliminating the laser damage should be taken into account for an IBC solar cell structure. Heavily doped uniform boron layer by fiber laser brings not only basic and essential conditions for the beginning step of IBC solar cell fabrication processes, but also the controllable doping concentration and depth that can be established according to the deposition conditions of layers.

• 한국재료학회지
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• 제1권3호
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• pp.125-131
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• 1991

pMOS소자의 $p^{+}$게이트 전극으로 다결정실리콘과 비정질실리콘을 사용하여 고온의 열처리 공정에 따른 붕소이온의 침투현상을 high frequency C-V plot, Constant Current Stress Test(CCST), Secondary Ion Mass Spectroscopy(SIMS) 및 Transmission Electron Microscopy(TEM)를 이용하여 비교하였다. C-V plot분석 결과 비정질실리콘 게이트가 다결정실리콘 게이트에 비해 flatband전압의 변화가 작게 나타났으며, 게이트 산화막의 절연파괴 전하밀도에서는 60~80% 정도 향상된 값을 나타내었다. 비정질실리콘 게이트는 증착시 비정질로 형성되는 구조로 인한 얇은 이온주입 깊이와 열처리 공정시 다결정실리콘에 비교하여 크게 성장하는 입자 크기 때문에 붕소이온의 침투 경로가 되는 grain boundary를 감소시켜 붕소이온 확산을 억제한 것으로 생각된다. Electron trapping rate와 flatband 전압 변화와의 관계에 대하여 고찰하였다.

• 한국표면공학회지
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• 제38권3호
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• pp.106-111
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• 2005

Ternary Ti-B-C coatings were synthesized on WC-Co and Si wafers substrates by a PECVD technique using a gaseous mixture of $TiCl_4,\;BCl_3,\;CH_4,\;Ar,\;and\; H_2$. The effects of deposition variables such as substrate temperature, gas ratio, $R_x=[BCl_3/(CH_4+BCl_3)]$ on the microstructure and mechanical properties of Ti-B-C coatings were investigated. From our instrumental analyses, the synthesized Ti-B-C coatings was confirmed to be composites consisting of nanocrystallites TiC, quasi-amorphous TiB2, and amorphous carbon at low boron content, on the contrary, nanocrystallites $TiB_2$, quasi-amorphous TiC, and amorphous carbon at relatively high boron content. The microhardness of the Ti-B-C coatings increased from $\~23 GPa$ of TiC to $\~38 GPa$ of $Ti_{0.33}B_{0.55}C_{0.11}$ coatings with increasing the boron content. The $Ti_{0.33}B_{0.55}C_{0.11}$ coatings showed lower average friction coefficient of 0.45, in addition, it showed relatively better wear behavior compared to other binary coatings of $TiB_2$ and TiC. The microstruture and microhardness value of Ti-B-C coatings were largely depend on the deposition temperature.

• 분석과학
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• 제13권6호
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• pp.705-711
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• 2000

리튬 이차전지용 부극 재료로 페놀 수지로 부터 유도된 boron을 doping한 polyacene에 구조적 특성, 표면 특성 및 전기적 특성을 연구하였다. Polyacene탄소질에 boron의 함유량을 각각 5%, 10%, 15%, 20% 첨가하여 특성화하였다. X-선 회절 결과에 따르면, 이들 시료들은 대표적인 무정형 탄소의 회절형태를 나타내었다. 표면 상태는 반구형의 표면상태를 가지고 있음을 SEM 결과로부터 알 수 있었다. 전지의 이온과 전자전달효과를 알아보기 위한 전기 화학적 충전/방전 특성과 임피던스 측정의 결과에 의하면, 10%와 15% boron이 첨가된 시료는 다소 우수한 특성을 나타내고 있다.