• Bulletin of the Korean Chemical Society
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• 제32권12호
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• pp.4371-4376
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• 2011

In this work, we investigate the growth behavior of silicon oxide nanowires via a solid-liquid-solid process. Silicon oxide nanowires were synthesized at $1000^{\circ}C$ in an Ar and $H_2$ mixed gas. A pre-oxidized silicon wafer and a nickel film are used as the substrate and catalyst, respectively. We propose two distinctive growth modes for the silicon oxide nanowires that both act as a unique solid-liquid-solid growth process. We named the two growth mechanisms "grounded-growth" and "branched-growth" modes to characterize their unique solid-liquid-solid growth behavior. The two growth modes were classified by the generation site of the nanowires. The grounded-growth mode in which the grown nanowires are generated from the substrate and the branchedgrowth mode where the nanowires are grown from the side of the previously grown nanowires or at the metal catalyst drop attached at the tip of the nanowire stem.

• 대한기계학회논문집A
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• 제33권8호
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• pp.733-738
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• 2009

Mechanical properties of <001> silicon nanowires are presented. In particular, predictions from the calculations based on different length scales, first principles calculations, atomistic calculations, and continuum nanomechanical theory, are compared for <001> silicon nanowires. There are several elements that determine the mechanics of silicon nanowires, and the complicated balance between these elements is studied. Specifically, the role of the increasing surface effects and reduced dimensionality predicted from theories of different length scales are compared. As a prototype, a Tersoff-based empirical potential has been used to study the mechanical properties of silicon nanowires including the Young's modulus. The results significantly deviates from the first principles predictions as the size of wire is decreased.

• 통합자연과학논문집
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• 제10권2호
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• pp.65-73
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• 2017

In this review paper, we will discuss about the methods of synthesizing Si nanowires by Top-down and Bottom-up. Silicon nanowires have a lot of application on various fields such as Li ion batteries, solar cells, chemical and biological sensors. We will address some of the applications of silicon Nanowires.

• 한국세라믹학회지
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• 제45권3호
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• pp.142-145
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• 2008

The growth of amorphous silica nanowires by on-site feeding of silicon and oxygen is reported. The nanowires were grown on a nickel-coated oxidized silicon substrate without external silicon or oxygen sources. Transmission electron microscopy observation revealed that the nanowires, which have diameters of less than 50 nm and a length of several micrometers, were grown using a traditional vapor-liquid-solid mechanism. Blue photoluminescence was observed from these nanowires at room temperature. An approach to grow nanowires without external precursors may be useful when integrating nanowires into devices structures. This can benefit the fabrication of nanowire-based nanodevices.

• 새물리
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• 제68권11호
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• pp.1203-1207
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• 2018

본 연구에서는 산소 함유량이 다른 산화 실리콘 막을 사용하여 실리카 나노 와이어를 형성하고, 실리카 나노 와이어의 미세구조 및 물리적 특성을 Si 웨이퍼를 사용하여 형성된 실리카 나노 와이어와 비교 분석하였다. 산화 실리콘 막은 플라즈마 화학 기상 증착 방법을 사용하여 제조하였으며, 실리카 나노 와이어는 산화 실리콘 막 표면에 촉매 물질로 니켈 막을 진공 증착한 후 열처리를 통해 형성하였다. 산소 함유량이 약 50 at.% 이하의 산화 실리콘 막의 경우 나노 와이어 형성 메커니즘, 미세구조 및 물리적 특성 등에서 실리콘 웨이퍼의 경우와 거의 차이점이 없었으며, 특히 나노 와이어의 굵기의 균일성은 산화 실리콘 막에서 더 우수한 거동을 나타내었다. 이러한 결과는 저가로 양질의 실리카 나노 와이어를 제조하는 대체재로서 산화 실리콘 막의 유용성을 제시한다.

• 한국전기전자재료학회논문지
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• 제20권2호
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• pp.101-105
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• 2007

We have synthesized silicon nanowires by using RFCVD(Radio Frequency Chemical Vapor Deposition) system on Au deposited p-type Si(100) wafers, and investigated their physical and electrical properties. The silicon nanowires had been grown in the atmospheres of $H_{2},\;N_{2}\;and\;SiH_{4}$ at 10 Torr at the substrate temperatures of $700{\pm}5^{\circ}C\;and\;810{\pm}5^{\circ}C$ respectively. FE-SEM analysis revealed that diameters of the silicon nanowires are $50{\sim}60nm$ with the length of several ${\mu}m$. XRD analysis showed that the growth direction of the nanowires is Si[111]. Field emission characteristics showed that the turn-of voltages at the current of $0.01\;mA/cm^{2}$ are $10\;V/{\mu}m\;and\;8.5\;V/{\mu}m$ for the wires grown at $700{\pm}5^{\circ}C\;and\;810{\pm}5^{\circ}C$, respectively.

• 통합자연과학논문집
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• 제6권3호
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• pp.170-175
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• 2013

Silicon nanowires were detached and obtained from silicon nanowire arrays on silicon substrate using a ultrasono-method. Silicon nanowire arrays on silicon substrate were prepared with an electroless metal assisted etching of p-type silicon. The etching solution was an aqueous HF solution containing silver nitrate. SEM observation shows that well-aligned nanowire arrays perpendicular to the surface of the silicon substrate were produced. After sonication of silicon nanowire array, an individual silicon nanowire was confirmed by FESEM. Optical characteristics of SiNWs were measured by FT-IR spectroscopy. The surface of SiNWs are terminated with hydrogen.

• 한국재료학회:학술대회논문집
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• 한국재료학회 2009년도 추계학술발표대회
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• pp.27.1-27.1
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• 2009

In recent years, ZnO nanostructures have drawn considerable attentions for the development of futuristic electronic devices due to their superior structural and optical properties. As the growth of ZnO nanowires by MOCVD is a bottom-up technique, the nature of substrates has a vital role for the dimension and alignment of the nanowires. However, in the pursuit of next generation ZnO based nanodevices, it would be highly preferred if well-ordered ZnO nanowires could be obtained on various substrates like sapphire, silicon, glass etc. Vertically aligned nanowires were grown on A and C-plane sapphire substrates, where as nanopencils were obtained on R-plane sapphire substrates. In addition, C-axis oriented vertical nanowires were also found using an interfacial layer(aluminum nitride film) on silicon substrates. On the other hand, long nanowires were found on Ga-doped ZnO film on glass substrates. Structural and optical properties of the ZnO nanowires on various substrates were also investigated.

• 한국재료학회:학술대회논문집
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• 한국재료학회 2009년도 춘계학술발표대회
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• pp.34.1-34.1
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• 2009

A great deal of attention has been focused on ZnO nanowires for various electronics and optoelectronics applications. in the pursuit of next generation nanodevices, it would be highly preferred if well-ordered ZnO nanowires of lower dimension could be fabricated on silicon. Before the growth of nanowires, silicon substrates were selectively etched using silicon nitride as masking layer. Vertical aligned ZnO nanowires were grown by metal organic chemical vapor deposition on patterned silicon substrate. The shape of nanostructures was greatly influenced by the micropatterned surface of the substrate. The aspect ratio, packing fraction and the number density of nanowires on top surface are around 10, 0.8 and $10^7\;per\;mm^2$, respectively, whereas the values are 20, 0.3 and $5\times10^7\;per\;mm^2$, respectively, towards the bottom of the cavity. XRD patterns suggest that the nanostructures have good crystallinity. High-resolution transmission electron microscopy confirmed the single crystalline growth of the ZnO nanowires along [0001] direction.

• ETRI Journal
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• 제31권4호
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• pp.351-356
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• 2009

We present a simple semiconductor process to fabricate nanogap arrays for application in molecular electronics and nano-bio electronics using a combination of freestanding silicon nanowires and angle evaporation. The gap distance is modulated using the height of the silicon dioxide, the width of the Si nanowires, and the evaporation angle. In addition, we fabricate and apply the nanogap arrays in single-electron transistors using DNA-linked Au nanoparticles for the detection of DNA hybridization.