Electronic Structure, Bonding, and Lithium Migration Effects of the Mixed Conductor β - LiAl

장건익(Gun-Eik Jang), I.M. Curelaru) 한국진공학회(ASCT) 1996 Applied Science and Convergence Technology Vol.5 No.3

전자구조(valence 와 conduction band) 해석을 통하여 이론상으로 현저한 금속 특성을 갖는다고 알려진 혼합 전도체 β-LiAl은 실제 이론과는 달리 Fermi level 에서 하나의 quasi-gap 이 존재하고 conduction 상태가 상당히 localized 되어 있음이 본 연구의 세부적 실험을 통하여 밝혀졌다. 또한 기계적 표면처리나 입자 bombardment(전자나 이온)을 통하여 야기되는, Li 이온의 복잡한 이동 거동에 관하여도 고찰하였다. Detailed experimental studies of the electronic structure of the valence and conduction bands of the mixed conductor β-LiAl indicate that a quasi-gap opens at the Fermi level, and the conduction states are highly localized, as opposed to the theoretical band structure calculations that predict predominant metallic behavior. Evidence for complex lithium migration effects involving the surface of LiAl, induced by particle (electron or ion) bombardment and mechanical treatment, has been obtained as a byproduct of these experiments.

SnO₂/Ag/SnO₂/SiO₂/Nb₂O₅ 다층막의 투명전극 특성

김진균 ( Jin-gyun Kim ), 장건익 ( Gun-eik Jang ) 충북대학교 산업과학기술연구소 2020 산업과학기술연구 논문집 Vol.34 No.2

SnO₂/Ag/SnO₂/SiO₂/Nb₂O₅ multi-layered thin films were deposited on glass substrate by RF/DC magnetron sputtering system. In order to estimate and compare with the experimental results, the simulation program, EMP (Essential Macleod Program) was adopted. EMP results suggested that the multi-layered thin film of SnO₂(40nm)/Ag(10nm)/SnO₂(30nm)/SiO₂(10nm)/Nb₂O₅(10nm) exhibited high transmittance of 90.1 % at 550 nm, whereas the experimentally measured transmittance showed 85.1 %, somewhat lower than simulation data, It was shown that the ΦTC value of SnO₂/Ag/SnO₂/SiO₂/Nb₂O₅ multi-layer film were in the range of 46.4- 62.1×10^-3Ω^-1.

MgF₂/Cr/MgF₂, MgF₂/Cu/MgF₂, MgF₂/Al/MgF₂ 다층박막의 광학적 특성

장강재(Kang-Jae Jang), 장건익(Gun-Eik Jang) 한국표면공학회 2007 한국표면공학회지 Vol.40 No.5

MgF₂/Cr/MgF₂, MgF₂/Cu/MgF₂ and MgF₂/Al/MgF₂ multi-layered thin films were fabricated by evaporation system. MgF₂ and Cr(Cu, And Al) was selected as a low refractive index material and mid reflector layer, respectively. Optical properties including color effect were systematically studied in terms of different film layer by using spectrophotometer. Experimental results were compared to the simulation result. The films consistings of MgF₂/Cr/MgF₂, MgF₂/Cu/MgF₂, MgF₂/Al/MgF₂ multi-layered thin films showed wavelength range of 430~780 ㎚, typically color range between greenish yellow and orange at view angle of 45˚. It was confirmed that this experimental result was well matched with simulation result.

제로에너지하우스 구현을 위한 부문별 요소기술 조합에 따른 에너지소비량 및 비용분석

신현철(Shin, Hyun-Cheol), 장건익(Jang, Gun-Eik) 한국건축친환경설비학회 2015 한국건축친환경설비학회 논문집 Vol.9 No.2

초음파를 조사한 유기화합물 수용액 속에서의 과산화수소 생성량의 측정

모세영(Se Young Mo), 장홍기(Hong Ki Chang), 이경재(Kyung Jae Lee), 장건익(Gun Eik Jang), 손종렬(Jong Ryeul Sohn) 大韓環境工學會 2000 대한환경공학회지 Vol.22 No.1

Thermal Evaporation법으로 제작한 ZnO 나노선의 온도와 산소유량에 따른 성장 특성

오원석,장건익,Oh,,Won-Seok,Jang,,Gun-Eik 한국전기전자재료학회 2008 전기전자재료학회논문지 Vol.21 No.8

Zinc oxide (ZnO) nanowires were prepared on Si substrates by a thermal evaporation method at different temperatures and $O_2$ pressure. Microstructural analysis of the obtained ZnO nanowires was performed by using transmission electron microscopy(TEM) and scanning electron microscopy(SEM). Phase analysis was done using X-ray diffraction(XRD). As the deposition temperature and oxygen pressure were increased, the diameter and length of ZnO nanowires had a tendency to increase. Based on TEM and XRD analyses, the nanowires are single crystalline in nature and consist of a single phase. According to the measurements, the ZnO nanowires grown at 1100$^{\circ}C$, Ar 50 sccm, $O_2$ 10 sccm have good properties.

Si₃N₄/SnZnO/AZO/Ag/Ti/ITO 다층 박막의 적층 횟수에 따른 광학적 특성

이상윤,장건익,Lee,,Sang-Yun,Jang,,Gun-Eik 한국전기전자재료학회 2015 전기전자재료학회논문지 Vol.28 No.1

In this study, $Si_3N_4$/SnZnO/AZO/Ag/Ti/ITO multi-layer film were prepared on glass substrate by DC/RF magnetron sputtering method. To prevent interfacial reaction between Ag and ITO layer, Ti buffer layer was inserted. Optical properties and sheet resistance were studied depending on laminating times of each multi-layered film especially in visible ray. The simulation program, EMP (essential macleod program), was adopted and compared with experimental data to expect the experimental result. It was found out that the transmittance of the first stacked $Si_3N_4$/SnZnO/AZO/Ag/Ti/ITO multi-layer film was more than 90%. However, with increasing stacking times, the optical properties of $Si_3N_4$/SnZnO/AZO/Ag/Ti/ITO multi-layer film get worse. Consequently, Ti layer is good for oxidation barrier, but too many uses of this layer may have an adverse effect to optical properties of TCO film.

Ga 첨가물이 ZnO의 전기적, 광학적 특성에 미치는 영향

김준식,장건익,Kim,,Jun-Sik,Jang,,Gun-Eik 한국전기전자재료학회 2010 전기전자재료학회논문지 Vol.23 No.9

ZnO with the wide band gap near 3.37 eV is typically an n-type semiconductor in which deviation from stoichiometry is electrically active. It was known that the films with a resistivity of the order of $10^{-4}{\Omega}cm$ is not easy to obtain. In order to improve electrical characteristic of ZnO, we added 1, 3, 5 wt% Ga element in ZnO. The Ga-doped ZnO (GZO) was grown on a glass substrate by radio frequency (RF) magnetron sputtering at the temperature range from 100 to $500^{\circ}C$. X-ray diffraction (XRD) patterns of GZO films showed preferable crystal orientation of (002) plane. The lowest resistivity of the GZO films was $8.9{\times}10^{-4}{\Omega}cm$. GZO films significantly influenced by the working temperature. The average transmittance of the films was over 80% in the visible ranges.

TiO₂/Si₃N₄/Ag/Si₃N₄/TiO₂ 다층구조에서 Si₃N₄ 버퍼층이 투과율에 미치는 영향

이서희,장건익,Lee,,Seo-Hee,Jang,,Gun-Eik 한국전기전자재료학회 2012 전기전자재료학회논문지 Vol.25 No.1

The $TiO_2/Si_3N_4/Ag/Si_3N_4/TiO_2$ multi layered structure was designed for the possible application of transparent electrodes in PDP (Plasma Display Panel). Multi layered film was deposited on a glass substrate at room temperature by DC/RF magnetron sputtering system and EMP (Essential Macleod Program) was adopted to optimize the optical characteristics of film. During the deposition process, the Ag layer in $TiO_2/Ag/TiO_2$ became heavily oxidized and the filter characteristic was degraded easily. In thus study, Si3N4 layer was used as a diffusion buffer layer between $TiO_2$ and Ag. in order to prevent the oxidation of Ag layer in $TiO_2/Si_3N_4/Ag/Si_3N_4/TiO_2$ structure. It was confirmed that $Si_3N_4$ layer is one of candidate materials acting as diffusin barrier between $TiO_2/Ag/TiO_2$.

PDMS 굴절 조정층이 Mn-Doped SnO₂ (MTO)/Ag/MTO/PDMS/MTO 투명전극의 특성에 미치는 영향

조영수,장건익,Jo,,Young-Su,Jang,,Gun-Eik 한국전기전자재료학회 2018 전기전자재료학회논문지 Vol.31 No.6

We fabricated highly flexible Mn-doped $SnO_2$ (MTO)/Ag/MTO/polydimethylsiloxane (PDMS)/MTO multilayer transparent conducting films. To reduce refractive-index mismatching of the MTO/Ag/MTO/polyethylene terephthalate (PET), index-matching layers were inserted between the oxide-metal-oxide-structured films and the PET substrate. The PDMS layer was deposited by spin-coating after adjusting the mixing ratio of PDMS and hexane. We investigated the effects of the index-matching layer on the color and reflectance differences with different PDMS dilution ratios. As the dilution ratio increased from 1:100 to 1:130, the color difference increased slightly, while the reflectance difference decreased from 0.62 to 0.32. The MTO/Ag/MTO/PDMS/MTO film showed a transmittance of 87.18~87.68% at 550 nm. The highest value of the Haacke figure of merit was $47.54{\times}10^{-3}{\Omega}^{-1}$ for the dilution ratio of 1:130.