Si-rich 산화 실리콘 박막 및 SiO₂/Si/SiO₂ 다층구조박막의 발광 특성

홍종성 三陟大學校 2000 論文集 Vol.33 No.3

SiO₂ target과 Si 웨이퍼 조각을 이용하여 Si-rich 산화규소 (silicon rich silicon oxide, SRSO) 박막 및 SiO₂/Si/SiO₂ 다층구조 박막을 RF 마그네트론 스퍼터링 (RF magnetron sputtring) 방법으로 형성하여 박막에 대한 발광특성을 조사하였다. 시료는 질소가스 분위기에서 900℃부터 100℃까지 급속 열처리 한 후 포토루미네슨스(photoluminesecnce, PL) 측정 결과 450 nm의 강한 PL 스펙트럼을 관찰할 수 있으며 실리콘 양의 증가에 따라 피크의 세기가 증가하였다. 발광의 근원을 연구하기 위하여 FTIR (Fourier transform infrared) 분관법을 이용하여 박막의 광학적 특성을 조사하였으며, 발광의 열적 재현성을 열처리 동안 조사하였다. Silicon rich silcon-oxide (SRSO) films and SiO₂/Si/SiO₂ multilayer sructures were deposited by rf magnetron sputtering system of compoung SiO₂ target and Si slces and the visibel blue photoluminescence (PL) of the silicon-oxide films has been characterized. After the deposition, thermal annealing was performed by rapid thermal annealer at tempeature from 900℃ to 110℃ for 10 min in N₂ atmosphere. In annealed films, the 450 nm peak in PL spectra appears strongly and the intensity of the main peak increase as the increase of silicon composition. In order to study the origin of the luminescence, optical properties of the SRSO films were evaluatel using the Fourier transform infrared (FTIR) spectroscopy and thermal reliabilities of the film luminescence were investigated during thermal anneals.

XPS분석을 통한 질화 텅스텐 박막의 급속 열처리 전후의 특성비교

홍종성 三陟大學校 1996 論文集 Vol.29 No.3

Tungsten nitride thin films have been deposited at 350℃ with the WF?-NH?-H? gas system by plasma enhanced chemical vapor deposition method, and the thermal properties of WN?/Si structure was investigated by X-ray photoemission spectroscopy(XPS) analyses. XPS depth profile show that the nitrogen composition in WN? films deposited with NH?/WF?=2/4 seem ratio is about 7 atomic %. And, the nitrogen composition are decreased under the 900℃ rapid thermal annealing to about 6 atomic %. The reduction of nitrogen composition in WN? film is believed to be the out-diffusion of the nitrogen atoms during RTA process. However, the severe silicidation are effectively suppressed by the deposition of WN? thin film instead of tungsten films. Therefore, it is thought that the thermal stability in WN?/Si structure are excellent.

플라즈마 화학 증착한 텅스텐 및 질화 텅스텐 박막의 미세구조 연구

홍종성 삼척대학교 1997 論文集 Vol.30 No.3

The fine structures for the tungsten and tungsten nitride thin films deposited bt plasma enhanced chemical vapor deposition technique were investigated with x-ray diffraction patterns. x-ray photoemission spectroscopy. and transmission electron microscopy techniques. Tungsten films have been deposited at 350℃ with the WF?-H₂gas systems and tungsten nitride films have been deposited at 350℃ with the WF?-NH₃-H₂gas systems. The resistivity of tungsten films were about 10?-㎝. and crystal structure was α-W (bcc structure). In the annealed films at 900℃. however, the metastable β-W and W silicide (WSi₂, W?Si?) peaks were observed. The resistivity of tungsten nitride films were about 70?-㎝, and crystal structure was W₂N(200), (α-W)+(β-W) and amorphous structures. In other words, the crystals of as-deposited WNx films are metastable in sturctures, but the thermal stability for the W/WNx/Si structure during high temperature annealing are excellent. Thermal stability of PECVD-WNx as a diffusion barrier reveals that the interdiffusions between Al or W and Si substrate can be prevented by N interstitial atoms in fcc-W₂N grains and grain boundaries.

실리콘 및 실리콘 산화막 위에 플라즈마 화학증착한 텅스텐 박막의 특성

홍치유,홍종성 동국대학교 자연과학연구소 1990 자연과학연구 논문집 Vol.10 No.-

플라즈마 화학증착법(Plasma-Enhanced Chemical Vapor Deposition ; PECVD) 으로 Si-웨이퍼 및 실리콘 산화막(SiO?) 위에 텅스텐 박막을 증착시켰다. WF?-H? 반응계에 비하여 WF?-SiH?-H? 반응계로 증착한 경우 비교적 낮은온도(200-300℃)에서 증착속도가 더 빠르고 비저항값이 더작은 텅스텐 박막을 얻을 수 있었다. 한편 산화막 위에도 PECVD 방법으로 텅스텐 박막을 증착할 수 있었으며 이 때의 박막 특성도 실리콘 웨이퍼를 기판으로 하여 증착한 텅스텐 박막의 특성과 비슷하였다. 텅스텐 박막의 결정 구조는 250℃(WF?-SiH?-H? 반응계) 및 300℃(WF?-H?)에서 증착하였을 때 안정상인 bcc 구조의 α-phase의 텅스텐이었다. Tungsten films were deposited on the silicon and the silicon dioxide by plasma-enhanced chemical vapor deposition method. Higher deposition rate and lower resistive PECVD-W films were obtained in WF?-SiH?-H? gas system in comparison with WF?-H? system on surface reaction temperatures of 200-300℃. Tungsten films can be deposited on silicon dioxide by PECVD method and the chracteristics of this films were much the same as the tungsten films on silicon. Structure of these films was body-centered cubic (α-phase tungsten).

RF 마그네트론 스퍼터링 방법으로 제작한 Ge-rich 실리콘 산화 박막(GRSO)의 2단계 급속열처리(RTA)후의 광학적 특성 연구

홍종성 三陟大學校 産業科學技術硏究所 2002 産業科學技術硏究論文集 Vol.7 No.3

Visible photoluminescence (PL) properties of the germanium-rich silicon oxide (GRSO) films were investigated. The GRSO films were prepared by rf magnetron co-sputtering with SiO_2 target and Ge slices. And these samples were one-step and two-step annealed at high temperatures. An intense photoluminescence (PL) in the blue-violet region around 540nm (2.3eV) was observed from these samples consisting of Ge nanocrystals (nc-Ge), GeO, GeO_2 embedded in a silicon oxide (SiO_2) matrix. The PL properties of GRSO films were compared with those of silicon rich silicon oxide (SRSO) films. XRD and XPS measurements strongly suggests the existence of Ge nanocrystal, GeO and GeO_2 in the SiO_2 matrices. And, it was found that the blue-violet PL intensity from GRSO layers reaches a maximum value after rapid thermal annealing (RTA) at 1100℃ for 10 min, and is more intense than the PL emission from SRSO films. PL intensity increases as the increases of annealing temperatures up to 1100℃, and it is believed that the RTA processes leads to the formation of Ge nanocrystals, GeO and GeO_2. FTIR spectra of GRSO films annealed at 1100℃ shows Ge-O-Ge bond. The possible mechanism of visible PL of GRSO films are discussed with these results.

RF 마그네트론 스퍼터링으로 성장한 Ge-rich 실리콘 산화박막(GRSO)의 광학적 특성

홍종성 三陟大學校 2001 論文集 Vol.34 No.3

The photoluminescence (PL) properties of germanium-rich silicon oxide (GRSO) films prepared by rf magnetron sputtering method on a silicon substrate were investigated and compared to those silicon-rich silicon oxide (SRSO) films. An visible photoluminescence was observed from GRSO films which were annealed at high temperatures. The samples grown under 50 W rf power shows a PL peak in blue-voilet region, and under 100 W rf power shows yellow region. In FTIR spectra of GRSO samples appear GE-O-Ge bond (TO mode) out of high temperature annealing. Rutherford backscattering spectrum was measured to study the extent of Ge concentrations. These results show the evidence that the neutral oxygen vacancy is believed to be responsible for the observed luminescence, and nanocrystalline Ge may contain new microstructure responsible for visible PL. It is therefore suggested that the mechanism of the visible PL can be discussed by a quantum confinement effect.

수소화된 n형 GaN에서 깊은준위 결함상태와 광전류 특성

홍종성 三陟大學校 2005 論文集 Vol.38 No.-

The n-type GaN layer has been grown on sapphire substrate by metalorganic chemical vapor deposition (MOCVD). To investigate the behaviors of deep levels for n-type GaN layer, persistent photoconductivity(PPC), photoconductivity(PC) and deep level transient spectroscopy (DLTS), and hydrogenation were performed at 100℃ and 200℃ for 2 hours. In order to prevent the oxidation of GaN layer, DLTS was measured at N₂ atmosphere. From DLTS measurements at high temperatures, three distinct deep levels, labeled N₃, N₄ and N5, werem measured in non-hydrogenated and hydrogenated n-type GaN. Their activation energies from different emission rates are calculated at 0.59eV, 0.67eV and 1.63eV below the conduction band, respectively. Their deep levels in the hydrogenated sample decrease in intensities than that in the non-hydrogenated GaN, and it was confirmed through PC, PPC, and DLTS measurements.

케이블 감속을 이용한 소형 로봇의 개발과 실시간 제어에 관한 연구

홍종성,이정완 江原大學校 産業技術硏究所 2002 産業技術硏究 Vol.22 No.B

In this thesis, a three degrees of freedom robot, which is able to provide sufficient precision for various robot researches, has been developed. The cable mechanism is used as a basic transmission of robot joints. Based on an optimal design strategy, link and joint parameters are determined and then overall geometry of the robot is designed. As an architecture of robot control, real time control system using real time linux and RtiC-Lab(Real Time Controls Laboratory) is developed. This system, written in C and based on Linux O/S, includes text editor, compiler, downloader, and real time plotter running in host computer for developing control purpose. Using these hardware and software, simple PD position control is implemented, the results shows the effectiveness of the system.

메탄올차량 배기가스 제거용 촉매의 저온활성에 관한 연구

洪鍾盛,丁碩鎭 경희대학교 환경연구소 1993 環境硏究 論文集 Vol.4 No.-

As the major methanol fueled vehicle exhaust components, formaldehyde & methanol conversion over the existing commercial 3-way catalyst was examined in a labolatory flow reactor system. The tested catalyst system were modified silver catalysts which contains different Ag loadings on commercial 3-way catalyst, and german commercial catalysts for methanol engine exhaust manufactured by Engelhard co. Ltd. Silver catalysts were prepared by the wet impregnation of silver nitrate solution on commercial 3-way catalyst. These catalysts were characterized with BET and PSD. In general, the formaldehyde(HCHO) conversion of the tested catalysts was similar to that of methanol(CH3OH). At 100,which is equivalent to the cold start condition, 5 wt% Ag cat. showed the most excellent HCHO and CH3OH conversion. The order of activity for conversion of HCHO & CH30H to carbon dioxide and water vapor was as follows; 5 wt% Ag/3-way cat. > 2 wt% Ag/3-way cat.>german cat. l(front)>german cat. 2(rear)>l0 wt% Ag/3-way cat.>3-wat catalyst. However there was no significant activity difference between those tested catalysts in the hot run condition of 400. Therfore, it could be concluded that the Ag-modified 3-way catalyst was the most effective and practical catalyst system which could be capable of removal the HCHO and methanol at the special condition of low temperature such as cold start condition.

Contour Method and Collapsibility Criteria for 2*3*K Contingency Tables

홍종성,손병욱,박지용 한국데이터정보과학회 2004 한국데이터정보과학회지 Vol.15 No.4

The contour method which was originally designed for contingency table is studied for and tables. Whereas a contour plot for a table is represented on unit squared two dimensional plane, a contour plot of a table can be expressed with a regular hexahedron on three dimensional space. Based on contour plots for categorical data fitted to all possible three dimensional log-linear models, one might identify whether or tables are collapsible over the third variable.