• JSTS:Journal of Semiconductor Technology and Science
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• 제14권1호
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• pp.92-95
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• 2014

In this work we have synthesized ZnS:Mn nanocrystals (NCs) using a simple one step thermochemical method. $Zn(NO_3)_2$ and $Na_2S_2O_3$ were used as the precursors and $Mn(NO_3)_2$ was the source of impurity. Thioglycolic acid (TGA) was used as the capping agent and the catalyst of the reaction. The structure and optical property of the NCs were characterized by means of X- ray diffraction (XRD), HRTEM, UV-visible optical spectroscopy and photoluminescence (PL). X-ray diffraction (XRD) and transmission electron microscopy (TEM) analyses demonstrated cubic phase ZnS:Mn NCs with an average size around 3 nm. Synthesized NCs exhibited band gap of about 4 eV. Photoluminescence spectra showed a yellow-orange emission with a peak located at 585 nm, demonstrating the Mn incorporation inside the ZnS particles.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2009년도 추계학술대회 논문집
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• pp.25-25
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• 2009

Zinc Oxide (ZnO) nanorod were grown on Si wafer by a thermal evaporation method at various temperatures. And their structure and optical properties were measured using Photoluminescence(PL), Scanning electron microscopy(SEM), and X-ray diffraction(XRD) analysis.

• 한국진공학회지
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• 제19권3호
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• pp.236-241
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• 2010

수열합성법을 이용하여 전구체 용액 농도에 따라 성장된 ZnO 나노막대의 특성에 대한 연구를 수행하였다. ZnO 씨앗층은 sol-gel법으로 코팅하였고, 그 위에 ZnO 나노막대는 전구체 용액 농도를 0.01 M에서 0.3 M로 변화하여 성장시켰다. FE-SEM (field-emission scanning electron microscopy), XRD (X-ray diffraction), PL (photoluminescence)을 사용하여 ZnO 나노막대의 특성 변화를 분석하였다. 전구체 용액의 농도가 증가함에 따라 ZnO 나노막대의 직경과 길이가 증가하였으며 광학적 특성이 향상되었다.

• 한국진공학회:학술대회논문집
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• 한국진공학회 2011년도 제40회 동계학술대회 초록집
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• pp.102-102
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• 2011

ZnO는 우수한 전기적, 광학적 특성으로 LED, solar cell 등과 같은 광전자소자의 응용을 목적으로 많은 연구가 진행되고 있다. 최근에는 ZnO 동종접합을 만들고자 많은 연구가 진행되고 있으나 p형 ZnO의 낮은 용해성과 높은 불순물에 따른 제조의 어려움으로 현재까지는 n형 ZnO만이 전도성 기판 위에 성장되어 응용되고 있다. 전도성 기판으로서 Si의 경우 낮은 가격, 공정의 용이함 등으로 GaN, SiC 등의 기판에 비하여 많은 응용이 가능하다. 따라서 본 연구에서는 전기화학증착법을 이용하여 p-n 접합을 형성하기 위하여 p형 Si 기판 위에 n형 ZnO 나노구조를 성장하고 그 특성을 분석하였다. 전기화학증착법은 낮은 온도 및 간단한 공정과정으로 빠른 성장 속도를 가지고 나노구조를 효과적으로 성장할 수 있는 방식이다. Seed 층 및 열처리에 따른 n형 ZnO 나노구조의 성장 특성 분석을 위하여 radio frequency (RF) magnetron 스퍼터를 사용하여 ZnO 및 Al doped ZnO (AZO) seed 층을 p형 Si 기판 위에 증착 후 다양한 온도로 열처리를 수행하였다. 질산아연(zinc nitrate)과 HMT가 희석된 용액에 KCl 촉매를 일정량 첨가한 후 다양한 공정 온도, 공정시간 및 질산아연의 몰농도를 변화시켜 n형 ZnO 나노구조를 성장하였다. 성장된 나노구조의 특성은 field emission scanning microscopy (FE-SEM), energy dispersive X-ray (EDX), photoluminescence (PL) 등의 장비를 사용하여 구조적, 광학적 특성을 분석하였다.

• 한국표면공학회:학술대회논문집
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• 한국표면공학회 2012년도 추계총회 및 학술대회 논문집
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• pp.127-128
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• 2012

ZnO nanostructures were grown by the hydrothermal method on ZnO seed layers post-heated in the range $350-500^{\circ}C$. The effects of the post-heated ZnO seed layers on the structural and optical properties of the ZnO nanostructures were investigated by scanning electron microscopy (SEM), X-ray diffraction (XRD) spectroscopy, and photoluminescence (PL) spectroscopy. The average grain sizes in the ZnO seed layers increased with increasing post-heating temperature, and nano-fibrous structures were observed on the surface of the ZnO seed layers post-heated at $450^{\circ}C$. The ZnO seed layers post-heated in the range $350-500^{\circ}C$ affected the residual stress, lattice distortion in the ZnO nanostructures and the intensity, positions, and full widths at half maximum of the 2-theta and PL peaks in the XRD and PL spectra for the ZnO nanostructures.

• 한국표면공학회지
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• 제41권4호
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• pp.169-173
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• 2008

The objective of this study is to coat the $SiO_2$ layer uniformly on the ZnS:Cu phosphors by using Sol-Gel method. From results of SEM micrographs observation, XRD and XPS analysis, it could be confirmed that $SiO_2$ layer was relatively well coated on ZnS:Cu particles. $Ag_2S$ was used as a decoding chemical to analyze the dense and uniform coating performance of $SiO_2$ layer on phosphor particles. It could be concluded that phosphors synthesized from our two step replacement method showed strong blue peak comparing to other method and rather weak green peak also. Obtained particle size of phosphors were about 20m diameter. Luminescence properties of the phosphors were examined by photoluminescence spectra at the excitation wavelength of 270 nm.

• 센서학회지
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• 제11권1호
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• pp.60-65
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• 2002

$ZnGa_2O_4$박막 형광체는 기판 온도 $550^{\circ}C$, 산소 분압 100mTorr에서 Si(100) 기판 위에 펄스레이저 증착법을 이용하여 증착시켰고, 이렇게 증착되어진 박막을 $600^{\circ}C$와 $700^{\circ}C$에서 후 열처리하여 발광 특성을 조사하였다. X-선 회절 실험 결과, 후열처리 온도를 증가시킴에 따라서 $Ga_2O_3$ 상이 나타남을 확인할 수 있었다. 발광 스펙트럼은 460nm에서 최고 피크값을 나타내었으며. 350에서 600nm까지 갖는 넓은 밴드의 발광 특성을 나타내었다. 후열처리에 따른 $ZnGa_2O_4$ 박막은 다른 형태의 발광 강도와 grain 크기를 나타내었다.

• 한국전기전자재료학회논문지
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• 제17권3호
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• pp.319-322
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• 2004

ZnO nanostructures were formed on a Si substrate by off-axis pulsed laser deposition(PLD) system in which a substrate plane was tilted toward a plume propagation direction. Atomic force microscopy (AFM) showed islands of 20∼40 nm width. From the x-ray diffraction (XRD) pattern exhibiting only (002) ZnO peak, the islands observed in AFM image were found to well crystallized. Optical bandgap enlargement from 3.26 eV to 3.35 and 3.47 eV due to the quantum size effect of ZnO nanostructures were observed by Photoluminescence (PL) at room temperature.

• 한국전기전자재료학회논문지
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• 제17권3호
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• pp.329-332
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• 2004

ZnO thin films were grown with different plume-substrate angles by pulsed laser deposition (PLD) to control the amount of ablated species arriving on a substrate per laser shot. The angles between plume propagation direction and substrate plane (P-S angle) were 0$^{\circ}$, 45$^{\circ}$ and 90$^{\circ}$. The growth time was changed in order to adjust film thickness. From the XRD pattern exhibiting a dominant (002) and a minor (101) XRD peak of ZnO, all films were found to be well oriented along c-axis. From the AFM image, it was found that the grain size of ZnO thin film was increased, as P-S angle decreased. UV intensity investigated by PL (Photoluminescence) increased as P-S angle decreased.

• 한국전기전자재료학회논문지
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• 제19권1호
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• pp.13-17
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• 2006

The one-dimensional ZnO nanostructures prepared through thermal evaporation under various cooling down procedures by changing the flow rates of the carrier gas and the reactive gas were investigated. The nanorod structures were changed into the nanonail types with a broad head through the reduction of the flow rate of the carrier gas. The decrease of the reactive gas reduced the length of the nail heads due to the limited mass transport of reactive gas. The intensity ratio of the ultraviolet emission/green emission of photoluminescence was proportional to the length of the broad head showing a larger surface area. The vertically aligned nanostructures were grown along the [0001] direction of ZnO regardless of the aligned directions. The crystal direction of the nanostructures was determined by that of the initial ZnO crystal.