• 공업화학
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• 제17권3호
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• pp.327-330
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• 2006

Si nanodot 배열을 형성하기 위하여 $NbO_{x}$ nanopillar를 건식식각 공정의 식각마스크로써 이용하기 위한 가능성이 조사되었다. $NbO_{x}$ nanopillar는 Al과 Nb의 양극산화 공정을 이용하여 준비되었다. $NbO_{x}$ nanopillar의 식각속도와 식각프로파일은 고밀도 플라즈마를 이용한 반응성 이온 식각법에 의해서 식각가스의 농도와 coil rf power, 그리고 dc bias voltage를 각각 변화시키면서 조사 되었다. $Cl_{2}$ 가스의 농도가 증가할수록 $NbO_{x}$ nanopillar의 식각속도는 감소하였고 coil rf power와 dc bias voltage의 증가는 식각속도의 상승을 초래했다. 선택된 식각조건에서 식각시간을 변화하여 $NbO_{x}$ nanopillar의 식각특성 및 식각메커니즘이 조사되었다.

• Journal of Magnetics
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• 제14권2호
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• pp.90-92
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• 2009

This study examined the current-induced spin wave excitation in asymmetric nanopillar junctions with a stack sequence of 20 nm Pt/10 nm Cu/7 nm NiFe/300 nm Cu, and a circular lateral dimension of 240 nm. An analysis of the magnetic and magnetotransport characteristics of the junction showed a possible spin transfer effect at this sample dimension when the magnetization was switched from a vortex state to another state. This finding is expected to help improve the understanding of the spin transfer torque phenomenon in nanopillar junctions.

• 센서학회지
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• 제25권6호
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• pp.447-452
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• 2016

In this study, we fabricated and evaluated the performance of film speaker using PVDF/ZnO NP composite structure. PVDF piezoelectric films were fabricated and characterized by XRD and SEM. ZnO nanopillars were prepared by hydrothermal synthesis on prepared PVDF piezoelectric films. We analyzed and tested the acoustic signal characteristics of the piezoelectric film. In order to fabricate an acoustic structure with a wide frequency range from low to high frequency, we have fabricated various types of film speakers and investigated the frequency characteristics. As a result, the fundamental piezoelectric properties of PVDF show that the piezoelectric constant due to ZnO NP increases. And the overall acoustic signal level is also increased by 10% or more. We investigated frequency generation from 500 Hz to 10 KHz using different sizes with PVDF/ZnO NP composite film speaker.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2009년도 춘계학술대회 논문집
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• pp.933-934
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• 2009

• 한국광학회:학술대회논문집
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• 한국광학회 2008년도 동계학술발표회 논문집
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• pp.161-162
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• 2008

• 한국전기전자재료학회논문지
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• 제28권11호
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• pp.711-714
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• 2015

In this paper, high quality AlN layers were regrown on AlN nanopillar structure with $SiO_2$-dots by HVPE. Surface morphology of AlN layer regrown exhibited flatter than a conventional AlN template. The laterally overgrown AlN regions would consist of a continuous well coalesced layer with lower dislocation density than in the template because of the dislocation blocking and dislocation bending effects. Moreover, result of Raman spectroscopy suggest that the AlN nanopillar structure with $SiO_2$-dots relieves the strain in the AlN layer regrown by HVPE.

• 한국소성가공학회:학술대회논문집
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• 한국소성가공학회 2008년도 춘계학술대회 논문집
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• pp.513-516
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• 2008

We have replicated nanopillar arrays using injection molding process of active heating and cooling method by several peltier devices. The injection melding has a high accuracy ed good reproducibility that are essential for mass production at low cost. Conventional molding processes widely use the water-based mold heating and air cooling methods. However, in case of replication for nano-patterned structures, it caused several defects such as air-flow mark, non-fill, sticking and tearing. In this study, periodic nano-scale patterns are replicated by using injection molding with Peltier devices. Porous nano-scale patterns, which have pore diameter range from 120nm to 150nm, were fabricated by using anodizing process. Periodic nano-pore structures ( $20mm\;{\times}\;20mm$) were used as a mold stamp of injection molding. Finally, PMMA with nanopillar arrays was obtained by injection molding process. By using the Peltier devices, the temperature of locally adiabatic molds can be dramatically controlled and the quality of the molded patterns can be slightly improved.

• 한국표면공학회지
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• 제55권6호
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• pp.342-352
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• 2022

Purine catabolite screening enables reliable diagnosis of certain diseases. In this regard, the development of a facile detection strategy with high sensitivity and selectivity is demanded for point-of-care applications. In this work, the simultaneous detection of uric acid (UA), xanthine (XA), and hypoxanthine (HX) was carried out as model purine catabolites by surface-enhanced Raman Spectroscopy (SERS). The detection assay was conducted by employing high-aspect ratio Au nanopillar substrates coupled with in-situ Au electrodeposition on the substrates. The additional modification of the Au nanopillar substrates via electrodeposition was found to be an effective method to encapsulate molecules in solution into nanogaps of growing Au films that increase metal-molecule contact and improve substrate's sensitivity and selectivity. In complex solutions, the approach facilitated ternary identification of UA, XA, and HX down to concentration limits of 4.33 𝜇M, 0.71 𝜇M, and 0.22 𝜇M, respectively, which are comparable to their existing levels in normal human physiology. These results demonstrate that the proposed platform is reliable for practical point-of-care analysis of biofluids where solution matrix effects greatly reduce selectivity and sensitivity for rapid on-site disease diagnosis.

• 정보저장시스템학회논문집
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• 제3권3호
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• pp.149-153
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• 2007

Perpendicular patterned magnetic media have been regarded as a prime candidate to achieve an ultra-high magnetic recording density of over 1 Tera-bits/$inch^2$. Patterned magnetic media with nanoscale patterns have been fabricated using various nanopatterning technologies. We focused on the two technical issues of nanoinjection molding technology. Firstly, we have investigated a cost-effective method to fabricate metallic stamps. Secondly, we focused on the analysis of nanoinjection molding with passive heating, where the replication of 50 nm nanopillar arrays was successful. The effect of the thermal insulation layer on the replication quality was examined by analytical and experimental methods. Finally, we deposited a magnetic layer on a injection molded nanopillars and measured. Our methodology can provide cost-effective mass-production for patterned magnetic media.

• 정보저장시스템학회논문집
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• 제3권3호
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• pp.144-148
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• 2007

In this paper, we analyzed the effect of the pattern height on the readback signal characteristics of the magnetic nanopillar tops and trench bottoms. In addition, we discuss the applicability of the present method to the production of patterned magnetic media, which can be obtained by depositing magnetic thin films on the molded nanopillars with passive heating. We found that the individual magnetic island deposited on each molded nanopillars with passive heating is a single magnetic domain and confirmed that its magnetization can be successfully reversed by applying an external magnetic field.