표면처리된 흑연 보트를 이용한 알루미늄의 증발 특성

정재인(J. I. Jeong),양지훈(J.H. Yang) 한국표면공학회 2009 한국표면공학회지 Vol.42 No.1

Resistive heating sources are widely used to prepare thin films by vapor deposition because they are cheap, and easy to install and handle in vacuum system. Graphite is one of materials used to make the resistive heating source, but until now only limited applications have been possible as it reacts easily with evaporating materials at high temperature. In this study, evaporation characteristics of aluminum have been investigated by using graphite boat thermally treated with BN powder. The employed graphite boat has been prepared by spray-coating BN power onto the cavity surface of the boat and thermal treatment with aluminum in vacuum at the temperature of more than 1400℃. The voltage-current characteristics as well as resistivity changes of the graphite boat have been investigated during aluminum evaporation according to the applied voltage and time. The evaporation aspect has been picturized during flash evaporation for 40 seconds based on the characterization results. The evaporation rate of the graphite boat has been compared with that of BN boat. The graphite boat showed some different characteristics compared with BN boat, in that the evaporation occurred at the last stage of flash evaporation. The film appearance according to the applied voltage has been compared, and also the reflectance of the resulting film has been investigated according to the film thickness. It has been found that the graphite boat thermally treated with BN powder can be used for aluminum evaporation without problem.

평면 표시형 구면경분석기의 분광 특성

정재인(J.I. Jeong),A. Kurokawa,S. Ichimura,J. Toth,K. Yoshihara,이영백(Y.P. Lee) 한국진공학회(ASCT) 1996 Applied Science and Convergence Technology Vol.5 No.3

새로운 형태의 2차원 평면 표시형 구변경분석기를 제조하여 그 특성을 평가하였다. 이 분석기는 고체 내에서 여기되어 방출된 전자의 에너지와 각도분포를 측정해서 해석하는데 사용하기 위한 것으로 궁극적으로는 비파괴적으로 단층적인 정보를 얻는 표면전자단층해석법 (Surface Electron Spectroscopic Tomography: SEN)를 개발하는 것을 목표로 하고 있다. 이 실험에 사용된 분석기는 H.Daimon 등이 개발한 것과 유사하나 외부에 미소 전자총을 사용한 점이 다르다. 그러나 미소전자총을 사용할 경우, 전자빔이 분석기에 인가된 전압에 의해 간섭을 받기 때문에 많은 문제점을 초래하게 된다. 본 연구에서는 이와 같은 경우에 발생된 제반 문제점과 이를 해결하기 위한 여러 가지 방안 그리고 조정된 분석기를 이용하여 실리콘 시편에서 얻은 Auger 스팩 트럼의 해석을 주로 기술하였다. A new display-type spherical mirror analyzer has been characterized in terms of the performance and the Auger spectra taken by using it. The final goal with the analyzer is to develop SET (Surface Electron Spectroscopic Tomography) which is capable to provide a 3-dimensional layer-by-Iayer information non destructively. This kind of analyzer was originally designed by H.Daimon. The main feature is to display 2-dimensional electronic structures directly onto a screen. In our case, an external micro-electron beam was employed as an excitation source. However, this invokes various problems because of the interference between the electron beam and the analyzer. The problems have been solved through the optimization of various parameters of the analyzer.

NdFeB 영구자석에의 Al/Al₂O₃ 다층막 코팅 및 부식 특성

정재인(J. I. Jeong),양지훈(J. H. Yang) 한국표면공학회 2009 한국표면공학회지 Vol.42 No.2

Various types of multilayer coatings including Al/Al₂O₃ structure have been prepared on Nd-Fe-B permanent magnet to modify the morphology of the coating and to enhance the corrosion resistance of the magnet. Magnetron sputtering has been employed to make the multilayer coatings. Al₂O₃ sputtering conditions were optimized in reactive sputtering by varying the deposition parameters. The formation of Al₂O₃ film was confirmed from the binding energy shift measured by electron spectroscopy for chemical analysis. 3 types of coating structures were designed and prepared by magnetron sputtering. The coating structures consist of (1) single Al coating, (2) modified coatings having oxide or plasma treated layer in the middle of coating structure, and (3) Al/Al₂O₃ multilayer coatings. Surface and cross-sectional morphologies showed that Al/Al₂O₃ multilayer grew as a layered structure, and that very compact Zone 3 like structure were formed. Xray diffraction peak showed that the crystal orientations of multilayer coatings were similar to that of the bulk powder pattern. Hardness increased drastically when the Al thickness was around 1im in the Al/Al₂O₃ multilayer. From the salt spray test and pressure cooker test, it has been shown that the multilayer coatings showed good corrosion resistance compared to Al single or modified layer coatings.

질화붕소가 스프레이코팅된 흑연과 용융 알미늄간의 진공에서의 반응기구

정재인(J. I. Jeong),임병문(B. M. Lim),문종호(J. H. Moon),홍재화(J. H. Hong),강정수(J. S. Kang),이영백(Y. P. Lee) 한국진공학회(ASCT) 1994 Applied Science and Convergence Technology Vol.3 No.1

질화붕소를 스프레이코팅한 흑연과 용융 알미늄간의 진공에서의 반응기구를 여러 가지 분석장치를 이용하여 조사하였다. 계면에 형성된 화합물층은 잘 정의된 형태를 보였으며, Al₄C₃와 Al_8B₄C_7의 혼합상이 흑연 바로 위에 형성되었고 그 위는 주로 AlN층으로 이루어져 있었다. 이러한 화합물의 생성과정과 반응기구를 자유에너지 관점에서 논의하였다. 이러한 방법으로 흑연 보우트를 제조하여 알미늄 증발에 이용하였을 경우, 매우 안정적인 증발 양상을 보였으며, 0.6 ㎛/min 이상의 매우 높은 증발율을 얻을 수 있음을 확인하였다. 또한 제조원가가 저렴하고 (TiB₂BN 보우트의 약 1/100), 전자빔 증발에 의해 형성된 피막과 비교하여 손색이 없는 피막을 얻을 수 있어 새로운 저항가열 증발원으로서의 이용 가능성을 확인하였다. We have investigated the reaction mechanism between BN-sprayed graphite and molten Al in vacuum using the various analytical tools. The interfacial compound layers were well-defined, and made mainly of AlN with underlying thin mixed layer of Al₄C₃ and Al_8B₄C_7. The analysis results were interpreted in terms of the free energy of formation. We prepared the BN-sprayed and annealed graphite boat, and evaluated the performance characteristics for the evaporation of Al. The evaporation was very stable, and also extended lifetime and enhanced rate up to 0.6 ㎛/min were obtained at a manufacturing cost of about 1% compared with current TiB₂ㆍBN boat.

전자빔 증발원을 이용한 물질의 증발 특성

정재인(J. I. Jeong),양지훈(J.H. Yang),박혜선(H.S. Park),정재훈(J.H. Jung),송민아(M.A. Song) 한국표면공학회 2011 한국표면공학회지 Vol.44 No.4

Electron beam evaporation source is widely used to prepare thin films by physical vapor deposition because it is very effective to vaporize materials and there is virtually no limit to vaporize materials including metals and compounds such as oxide. In this study, evaporation characteristics of various metals and compounds from an electron beam evaporation source have been studied. The 180 degree deflection type electron beam evaporation source which has 6-hearth crucibles and is capable of inputting power up to 10 ㎾ was employed for evaporation experiment. 36 materials including metals, oxides and fluorides have been tested and described in terms of optimum crucible liner, evaporation state, stability, and so on. Various crucible liners have been tried to find out the most effective way to vaporize materials. Two types of crucible liners have been employed in this experiment. One is contact type liner, and the other is non-contact type one. It has been tried to give the objective information and the most effective evaporation method on the evaporation of materials from the electron beam evaporation source. It is concluded that the electron beam evaporation source can be used to prepare good quality films by choosing the appropriate crucible liner.

Valence Band Photoemission Study of Co / Pd Multilayer

강정수(J.-S. Kang),강상국(S.K. Kim),정재인(J.I. Jeong),홍재화(J.H. Hong),이영백(Y.P. Lee),신현준(H.J. Shin),C. G. Olsong(C. G. Olsong) 한국자기학회 1993 韓國磁氣學會誌 Vol.3 No.1

We report the photoemission (PES) studies for the Co /Pd multilayer. The Co 3d PES spectrum of Co /Pd exhibits two interesting features, one near the Fermi energy, E_F, and another at ~2.5 eV below E_F. the Co 3d peak near E_F of Co /Pd is much narrower than that of the bulk Co, consistent with the enhanced Co magnetic moment in Co /Pd compared to that in the bulk Co. The Co 3d feature at ~ -2.5 eV resembles the Pd valence band structures, which suggests a substantial hybridization between the Co and Pd sublayers. The Co 3d PES spectrum of Co /Pd is compared with the existing band structures, obtained using the local spin density functional calculations. A reasonable agreement is found concerning the bandwidth of the occupied part of the Co 3d band, whereas a narrow Co 3d peak near E_F seems not to be described by the band structure calculations.

강판 표면의 Temper Color층 분석

홍재화(J.H. Hong),강정수(J.S. Kang),정재인(J.I. Jeong),전인준(I.J. Jeon),이영백(Y.P. Lee) 한국진공학회(ASCT) 1992 Applied Science and Convergence Technology Vol.1 No.2

냉연강판의 성능은 그 표면 상태에 의해서 많은 영향을 받는다. Temper-color(T/C)층은 tempering 과정 중 형성되는 다양한 색깔의 얇은 산화층으로서, 우수한 표면 품질을 갖기 위해서는 방지 또는 제어되어져야 한다. T/C 현상을 이해하기 위하여 여러 가지 표면 분석방법이 동원되었다. 유백색 T/C층의 표면은 1 ㎛ 크기의 구형의 미세구조로 구성되어 있었다. 소둔과정 중 C, Si, Mn과 Al이 표면으로 농화됨을 알았고, Mn과 C은 정상시료에서 보다 T/C 시료에서 농화가 심하였다. T/C 시료에서의 산화층 두께는 정상시료의 60-100 Å 보다 매우 두꺼웠으나, 발생 정도에 따라 변화하였다. T/C층 내의 각 원소 산화 상태는, Si은 SiO₂의 상태로, Mn은 MnO나 MnO₂의 상태로 Fe는 극표면층의 Fe₂O₃ 상태를 제외하고는 metallic 상태로 분석되었다. The performance of the cold-rolled steel sheet is affected strongly by the surface conditions. Temper-colored (T/C) layer, which is the formation of a thin colored layer on the surface in the tempering process, is one of the phenomena which should be overcome to secure the improved surface quality. The layers were exposed to a variety of surface-analysis techniques for the characterization. The surface of milky-color T/C film consists of droplet-shaped microstructures in the size of around 1 ㎛. C, Si, Mn and Al are segregated to the surface during annealing. Mn and C are found to be more enriched at the surface of T/C sample than the normal one. The thickness of the oxide of T/C sample is much larger than the normal one of 60-100 Å, but varies in a wide range according to the degree of T/C. The oxidation state of Si in T/C film was analyzed to be SiO₂, and that of Mn to be MnO or MnO₂. On the contrary, Fe was metallic with Fe₂O₃ phase only at the extreme surface.

시베리아 산불이 2003년 봄철 동아시아 오존 농도에 끼치는 영향 연구

박록진(Rokjin J. Park),정재인(Jaein I. Jeong),윤대옥(Daeok Youn) 한국기상학회 2009 대기 Vol.19 No.3

Cd / Pd 광자기 다층박막에 있어서의 Co 단층두께 및 계면형상이 수직자기 이방성에 미치는 영향

김상국(S.K.Kim),정재인(J.I.Jeong),홍재화(J.H.Hong),강정수(J.S.Kang),구양모(Y.M.Koo),이영백(Y.P.Lee),윤두섭(D.S.Yoon),장윤기(Y.K.Jang) 한국자기학회 1991 한국자기학회 학술연구발표회 논문개요집 Vol.1 No.1

AES의 원리 및 응용

이영백(Y. P. Lee),홍재화(J. H. Hong),강정수(J. S. Kang),정재인(J. I. Jeong) 한국표면공학회 1990 한국표면공학회지 Vol.23 No.2