• Proceedings of the Korean Institute of Surface Engineering Conference
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• 2014.11a
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• pp.104-105
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• 2014

마이크로 패턴된 Au 전극사이에 얼라인된 Tellurium (Te) 나노리본들이 의도한 모양과 배열방식을 가지고 리쏘그래피 패턴 전해증착 (Lithographically patterned nanowier electrodepositon, LPNE) 방법에 의해 4인치 Si wafer 배치로 합성되었다. 합성된 Te 나노리본은 수 센티미터의 길이를 가지고, 그 두께와 폭 역시 작업 전극으로 사용되는 Si wafer위에 증착된 Ni의 두께와 전해증착 시간에 의해 쉽게 제어될 수 있다. $3{\mu}m$의 간격을 갖는 Au 전극 사이에 얼라인된 두께 ~100nm의 Te 나노리본들은 전해증착에 의해 그 폭이 제어되었고, 각각의 다른 폭을 갖는 증착된 하나의 Te 나노리본들의 IV 및 FET 측정을 통하여 나노리본 폭의 변화에 따른 전기적 특성 (비저항, FET 이동도 및 FET 캐리어 농도)이 평가되었다.

• Journal of the Microelectronics and Packaging Society
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• v.15 no.4
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• pp.41-49
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• 2008

Thermoelectric properties of the n-type Bi-Te and the p-type Bi-Sb-Te films were measured and the growth behaviors of the electrodeposited Bi-Te and Bi-Sb-Te nanowires were characterized. Filling ratios of 81% and 77% were obtained for electrodeposition of the Bi-Te and the Bi-Sb-Te nanowires, respectively, into the nano pores of 200 nm-diameter of an alumina template. A thermoelectric module, composed of the Bi-Te nanowires and the Bi-Sb-Te nanowires was processed by electrodeposition, and a resistance value of $15{\Omega}$ was measured between the Ni electrodes formed on the Bi-Te nanowires and the Bi-Sb-Te nanowires of the module.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.27 no.1
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• pp.1-8
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• 2017

Catalytic synthesis and properties of ${\beta}-Ga_2O_3$ nanowires grown by metal organic chemical vapor deposition are reported. Au, Ni and Cu catalysts were suitable for the growth of $Ga_2O_3$ nanowires under our experimental conditions. The $Ga_2O_3$ nanowires grown by using Au, Ni and Cu catalysts showed different growth rates and morphologies in each case. We found the $Ga_2O_3$ nanowires were grown by the Vapor-Solid (VS) process when Ni was used as a catalyst while the Vapor-Liquid-Solid (VLS) was a dominant process in case of Au and Cu catalysts. Also, we found nanowires showed different optical properties depend on catalytic metals. On the other hand, for the cases of Ti, Sn and Ag catalysts, nanowires could not be obtained under the same condition of Au, Cu and Ni catalytic synthesis. We found that these results are related to the different characteristics of each catalyst, such as, melting points and phase diagrams with gallium metal.

• Bulletin of the Korean Chemical Society
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• v.32 no.12
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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.

• Proceedings of the Materials Research Society of Korea Conference
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• 2012.05a
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• pp.87.1-87.1
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• 2012

넓은 밴드갭 (3.37eV)과 높은 엑시톤 결합에너지 (60meV)를 가지는 ZnO 물질은 ultra violet light 센서 및 light emitting diode (LED)의 재료로써 많은 연구가 진행되고 있다. 특히 나노와이어 구조를 이용하여 소자를 만들 경우 양자효과와 1차원적 캐리어 수송경로 효과로 인하여 그 특성을 보다 향상 시킬 수 있다. 나노와이어를 이용한 이종접합 p-n 다이오드를 제작하기 위하여 ZnO와 격자상수가 비슷한 GaN, NiO, CoO와 같은 물질들이 나노구조 접합에 많이 쓰이고 있지만, 격자상수 차이로 인해서 접합부분 캐리어 수송효율이 떨어지는 단점을 가지고 있다. n-type과 p-type ZnO를 만들어 동종 접합을 만들 경우 이러한 문제점을 극복할 수 있지만, 도핑되지 않은 ZnO가 n-type을 특성을 나타내기 때문에 안정적인 p-type ZnO 합성에 대한 연구가 필수적이다. 본 연구에서는 안정적인 p-type ZnO 합성을 위해서 수열합성법을 이용하여 phosphorus (P) 도핑을 하였고, 나노와이어 diode 구조를 만들었다. P 도핑으로 인한 격자상수 변화는 x-ray diffraction (XRD)를 사용하여 확인하였고, x-ray photoelectron spectroscopy (XPS)를 통해 도핑 원소를 분석하였으며, 이때의 recification ratio, turn-on voltage 등의 전기적 특성을 평가하였다.

• Journal of the Korean Vacuum Society
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• v.19 no.4
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• pp.307-313
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• 2010

One-dimensional cubic phase silicon carbide nanowires (${\beta}$-SiC NWs) were efficiently synthesized by thermal chemical vapor deposition (TCVD) with mixtures containing Si powders and nickel chloride hexahydrate $(NiCl_2{\cdot}6H_2O)$ in an alumina boat with a carbon source of methane $(CH_4)$ gas. SEM images are shown that the growth temperature (T) of $1,300^{\circ}C$ is not enough to synthesize the SiC NWs owing to insufficient thermal energy for melting down a Si powder and decomposing the methane gas. However, the SiC NWs could be synthesized at T>$1,300^{\circ}C$ and the most efficient temperature for growth of SiC NWs is T=$1,400^{\circ}C$. The synthesized SiC NWs have the diameter with an average range between 50~150 nm. Raman spectra clearly revealed that the synthesized SiC NWs are forming of a cubic phase (${\beta}$-SiC). Two distinct peaks at 795 and $970 cm^{-1}$ in Raman spectra of the synthesized SiC NWs at T=$1,400^{\circ}C$ represent the TO and LO mode of the bulk ${\beta}$-SiC, respectively. XRD spectra are also supported to the Raman spectra resulting in the strongest (111) peaks at $2{\Theta}=35.7^{\circ}$, which is the (111) plane peak position of 3C-SiC. Moreover, the gas flow rate of 300 sccm for methane is the optimal condition for synthesis of a large amount of ${\beta}$-SiC NW without producing the amorphous carbon structure shown at a high methane flow rate of 800 sccm. TEM images are shown two kinds of the synthesized ${\beta}$-SiC NWs structures. One is shown the defect-free ${\beta}$-SiC NWs with a (111) interplane distance of 0.25 nm, and the other is the stacking-faulted ${\beta}$-SiC NWs. Also, TEM images exhibited that two distinct SiC NWs are uniformly covered with $SiO_2$ layer with a thickness of less 2 nm.

• Membrane Journal
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• v.33 no.4
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• pp.211-221
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• 2023

This study presents a comprehensive study on the synthesis and characterization of PVI-PGMA/LiTFSI polymeric membrane electrolytes and CxNy-C flexible electrodes for energy storage applications. The dual-functional PVI-PGMA copolymer exhibited excellent ionic conductivity, with the PVI-PGMA73/LiTFSI200 membrane electrolyte achieving the highest conductivity of 1.0 × 10^-3 S cm^-1. The electrochemical performance of the CxNy-C electrodes was systematically investigated, with C3N2-C demonstrating superior performance, achieving the highest specific capacitance of 958 F g^-1 and lowest charge transfer resistance (R_ct) due to its highly interconnected hybrid structure comprising nanowires and polyhedrons, along with binary Co/Ni oxides, which provided abundant redox-active sites and facilitated ion diffusion. The presence of a graphitic carbon shell further contributed to the enhanced electrochemical stability during charge-discharge cycles. These results highlight the potential of PVI-PGMA/LiTFSI polymeric membrane electrolytes and CxNy-C electrodes for advanced energy storage devices, such as supercapacitors and lithium-ion batteries, paving the way for further advancements in sustainable and high-performance energy storage technologies.