• 한국진공학회:학술대회논문집
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• 한국진공학회 2009년도 제38회 동계학술대회 초록집
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• pp.74-74
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• 2010

One-dimensional nanosturctures such as nanowires and nanotube have been mainly proposed as important components of nano-electronic devices and are expected to play an integral part in design and construction of these devices. Silicon carbide(SiC) is one of a promising wide bandgap semiconductor that exhibits extraordinary properties, such as higher thermal conductivity, mechanical and chemical stability than silicon. Therefore, the synthesis of SiC-based nanowires(NWs) open a possibility for developing a potential application in nano-electronic devices which have to work under harsh environment. In this study, one-dimensional nanowires(NWs) of cubic phase silicon carbide($\beta$-SiC) were efficiently produced by thermal chemical vapor deposition(T-CVD) synthesis of mixtures containing Si powders and hydrocarbon in a alumina boat about $T\;=\;1400^{\circ}C$ SEM images are shown that the temperature below $1300^{\circ}C$ is not enough to synthesis the SiC NWs due to insufficient thermal energy for melting of Si Powder and decomposition of methane gas. However, the SiC NWs are produced over $1300^{\circ}C$ and the most efficient temperature for growth of SiC NWs is about $1400^{\circ}C$ with an average diameter range between 50 ~ 150 nm. Raman spectra revealed the crystal form of the synthesized SiC NWs is a cubic phase. Two distinct peaks at 795 and $970\;cm^{-1}$ over $1400^{\circ}C$ represent the TO and LO mode of the bulk $\beta$-SiC, respectively. In XRD spectra, this result was also verified with the strongest (111) peaks at $2{\theta}=35.7^{\circ}$, which is very close to (111) plane peak position of 3C-SiC over $1400 ^{\circ}C$ TEM images are represented to two typical $\beta$-SiC NWs structures. One is shown the defect-free $\beta$-SiC nanowire with a (111) interplane distance with 0.25 nm, and the other is the stacking-faulted $\beta$-SiC nanowire. Two SiC nanowires are covered with $SiO_2$ layer with a thickness of less 2 nm. Moreover, by changing the flow rate of methane gas, the 300 sccm is the optimal condition for synthesis of a large amount of $\beta$-SiC NWs.

• 전기화학회지
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• 제13권1호
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• pp.70-74
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• 2010

전기화학 반응을 이용한 실리콘 표면상으로의 단백질 고정을 연구하였다. 이를 위해 Nitrobenzendiazonium(NiBD) 양이온을 화학적 환원반응을 통해 수식하고 수식된 실리콘 표면을 전기화학적으로 다시 환원시켜 나이트로 기능기를 일차아민 기능기로 활성화하여 단백질 고정에 이용하였다. 활성화 된 표면에 금 나노입자를 고정하여 일차 아민 생성을 확인하였다. 또한 이 방법을 응용하여 실리콘 나노선 어레이 중 선택된 나노선 만을 활성화하고 단백질을 선택적으로 고정하는 연구를 수행하였다. 이 연구를 통하여 NiBD 양이온의 화학 및 전기화학 반응이 실리콘 나노선 표면으로 단백질의 선택적 고정화에 유용하게 사용될 수 있음을 보였다.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2005년도 하계학술대회 논문집 Vol.6
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• pp.7-8
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• 2005

Silicon(Si) nanowires have been grown by thermal chemical vapor deposition using the 20h ball-milled SiO powders under controlled conditions without the catalyst. For the synthesis of Si nanowires, $Al_2O_3$ substrates were used. Current-Voltage(I-V) and photoresponses were measured for the single Si nanowire in vacuum at room temperature. The light sources for these measurements were the 325 nm wavelength line from a He-Cd laser and the 633 nm wavelength line from a He-Ne laser. The intensity of the photoresponse is independent of the illumination time. And rise and decay times of the photoresponses are shorter than 1 sec.

• Current Photovoltaic Research
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• 제2권3호
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• pp.130-134
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• 2014

We have fabricated the selective emitter solar cell using double textured nanowires structure. The $40{\times}40mm2$-sized silicon substrates were textured to form the pyramid-shaped surface and the nanowires were fabricated by metal assisted chemical etching process using Ag nanoparticles, subsequently. The heavily doped and shallow emitters for selectiv eemitter solar cells were prepared through the thermal $POCl_3$ diffusion and chemical etch-back process, respectively. The front and rear electrodes were prepared following conventional screen printing method and the widths of fingers have been optimized. The selective emitter solar cell using double textured nanowires structure achieved a conversion efficiency of 17.9% with improved absorption and short circuit current density.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2005년도 추계학술대회 논문집 Vol.18
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• pp.115-116
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• 2005

Si nanowires (NWs) were fabricated in vacuum furnace by using a Nd:YAG pulsed laser with the wavelength of 325 nm. Commercial p-type Si wafer is used for target, and any catalytic materials are not used. Scanning electron microscopy (SEM) images indicate that the diameters of Si NWs ranged from 10 to 150 nm. Si NWs have various size and shape with a substrate position inside a furnace, and their morphologic construction is reproducible. The formation mechanism of the NWs is discussed.

• 전기화학회지
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• 제12권1호
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• pp.40-46
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• 2009

실리콘 표면을 전기화학적으로 활성화하여 활성화된 표면에만 선택적으로 단백질이나 나노입자 등의 기능성 물질을 고정화하는 방법을 개발하였다. 이를 위해 Carboxymethylbenzendiazonium (CMBD) 양이온을 전기화학적 환원반응을 통해 고정하여 실리콘 표면을 활성화하는 방식을 선택하였다. 그리고 활성화 된 표면에서만 기능성 물질이 고정된 것을 확인함을 통하여 CMBD 양이온의 사용이 선택적 고정화에 매우 효과적임을 보였다. 나아가 이 방법을 응용하여 실리콘 나노소자에 탑재된 실리콘 나노선 어레이 중 선택된 나노선의 표면만을 활성화하고 금 나노입자를 선택적으로 고정하는 연구를 수행하였다.

• 대한기계학회논문집B
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• 제39권10호
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• pp.825-829
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• 2015

나노선에서 코어-셸 헤테로 구조를 도입함으로써 열 전도율을 낮출 수 있으며, 이로 인해 열전 효율(ZT)을 향상시킬 수 있다는 것이 이론 연구를 통해 제안되었다. 본 논문에서는 코어-셸 나노선의 열전도율 감소를 실험적인 방법을 통해 확인하였다. 화학증기 증착법을 통해 만든 게르마늄-규소 $_x$ 게르마늄 $_{1-x}(Ge-Si_xGe_{1-x})$ 코어-셸 나노선의 열전도율을 마이크로 크기의 뜬 디바이스를 이용하여 측정하였다. 셸에서 측정된 실리콘의 함유율(x)는 0.65 로 확인하였으며, 게르마늄은 코어와 셸 사이에서, 격자 불일치(lattice mismatch)에서 비롯된 결점(defect)와 같은 역할을 한다. 또한, 4-point I-V 측정실험에, 휘트스톤 브릿지 실험을 추가 진행함으로써 측정 민감도를 강화하였다. 측정된 열전도율은 상온에서 9~13 W/mK 으로써, 비슷한 지름을 가지는 게르마늄 나노선과 비교하였을 때, 열전도율이 약 30 % 낮아졌음을 확인하였다.

• 한국재료학회:학술대회논문집
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• 한국재료학회 2007년도 춘계학술발표대회 및 제12회 신소재 심포지엄
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• pp.28.2-28.2
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• 2007

• 한국진공학회:학술대회논문집
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• 한국진공학회 2013년도 제45회 하계 정기학술대회 초록집
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• pp.266.2-266.2
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• 2013

According to advanced nanotechnology, the nanostructured materials with various kinds and shape are synthesized easily or produced by process. Recently, researches about interaction between the nanostructured materials and biological system have been progressed actively. The surface topography may influence cellular responses, for example cell adhesion, cell morphology. In this work, we synthesized vertically aligned silicon nanowires (SiNWs) on the Au-covered Si(111) wafer by chemical vapor deposition (CVD) method. We accomplished to control of the SiNWs diameter by regulating thickness of Au film such as 1 nm and 10 nm. These substrates did not isolate cells and just provided surface topography for cell culture. Human Embryonic Kidney 293T cells (HEK 293T cells) were cultured on these substrates for 2 days. We studied the nanotopographical effects on cell morphology, adhesion, and growth which are evaluated on each SiNWs substrate comparing bare glass as control.

• Advances in nano research
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• 제7권2호
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• pp.99-108
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• 2019

Higher-order theories are very important to investigate the mechanical properties and behaviors of nanoscale structures. In this study, a free vibration behavior of SiNW resting on elastic foundation is investigated via Eringen's nonlocal elasticity theory. Silicon Nanowire (SiNW) is modeled as simply supported both ends and clamped-free Euler-Bernoulli beam. Pasternak two-parameter elastic foundation model is used as foundation. Finite element formulation is obtained nonlocal Euler-Bernoulli beam theory. First, shape function of the Euler-Bernoulli beam is gained and then Galerkin weighted residual method is applied to the governing equations to obtain the stiffness and mass matrices including the foundation parameters and small scale parameter. Frequency values of SiNW is examined according to foundation and small scale parameters and the results are given by tables and graphs. The effects of small scale parameter, boundary conditions, foundation parameters on frequencies are investigated.