http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.
변환된 중국어를 복사하여 사용하시면 됩니다.
$ZnSe_{1-x}:Te_x$ 박막의 제작과 광학적 특성에 관한 연구
이홍찬,Lee Hong-Chan 한국마린엔지니어링학회 2006 한국마린엔지니어링학회지 Vol.30 No.1
In this study, systematical investigations were carried out on crystal qualifies and optical properties of $ZnSe_{1-x}:Te_x$ (x=0.002-0.04) thin films frown by molecular beam epitaxy (MBE). The crystal qualifies and optical properties have been investigated by X-ray diffraction (XRD) and Photoluminescence (PL) measurements, respectively. From the XRD measurements, the crystallographic characteristics showed mediocre crystal quality with increasing the Te composition. From the PL measurements, emission in the visible spectrum region from blue to green was obtained by varying the Te content of the ZnSe:Te epilayers. The efficient blue and green emission were attributed to the recombination of excitons trapped at isoelectronic isolated a single Te atom and $Te_n(n{\geq}2)$ clusters. respectively. The blue emission become dominant in Te tightly doped $ZnSe_{1-x}:Te_x$ $(Te=0.2\%)$ epilayers with increasing temperature. For the Te heavily doping condition $(Te=4.0\%)$, the dominant green emission could be observed at around 160K.
Preparation of Non-flammable Wiper Paper by Simple H<sub>3</sub>PO<sub>3</sub> Treatment
이홍찬,이시춘,Lee, Hong Chan,Lee, Shichoon Convergence Society for SMB 2020 융합정보논문지 Vol.10 No.6
매우 얇고 다공성 비인화성 와이퍼 용지를 아인산 수용액 처리에 의해 준비되었다. H<sub>3</sub>PO<sub>3</sub> 처리는 와이퍼 용지의 난연성을 불연성 수준으로 개선시켰다. 열중량 분석 결과 700℃에서 잔량이 50%까지 증가했다. 이것은 본 실험과 같은 아인산 처리가 셀룰로오스 사슬의 탈수를 돕고, 연소중에 차르(char)와 유사한 구조의 형성을 촉진한다는 것을 의미한다. FT-IR과 X선 광전자 분광학에서는 H<sub>3</sub>PO<sub>3</sub>의 일부분은 셀룰로오스 사슬의 작용기와 반응하는 것으로 보였다. 반응한 아인산은 셀룰로오스의 체인의 탈수를 촉진하고, 차르와 같은 구조의 형성을 도와 와이퍼 용지의 난연성을 향상시킨다. A thin and porous non-flammable wiper was prepared by phosphorus acid solution treatment and subsequent oven annealing. The H<sub>3</sub>PO<sub>3</sub> treatment improved flame retardancy of wiper paper to nonflammable level. Thermogravimetric analyses showed that residues increased to 50% at 700℃, which means this treatment helps dehydration of the cellulose chain and promotes the formation of char-like structures during the burning. FT-IR and X-ray photoelectron spectroscopy showed that some of the added H<sub>3</sub>PO<sub>3</sub> could react with the functional groups of the cellulose chain. The reacted H<sub>3</sub>PO<sub>3</sub> components promote dehydration of the cellulose components and the formation of a char-like structure and improve the flame retardancy of the wiper paper.
이온성 액체 첨가를 통한 폴리카보네이트의 난연성 향상 연구
이홍찬,이시춘,Lee, Hong Chan,Lee, Shichoon 한국섬유공학회 2016 한국섬유공학회지 Vol.53 No.6
Flame-retardant polycarbonates have been produced by addition of metal sulfonate compounds. However, the process is to be validated for thin-walled products. In this study, to improve flame retardancy of polycarbonate, an ionic liquid was additionally added. With a decrease in the second combustion time, a small quantity of the ionic liquid as less as 0.05 phr was enough to effectively meet the UL94 V0 protocol. Thermogravimetric experiments showed that the maximum weight loss rate increased with addition of the ionic liquid, indicating the sudden decomposition of polycarbonate. This sudden decomposition increased the rate of formation of char components during flaming, resulting in improvement of flame retardancy of polycarbonate.
Te Cluster 제어에 의한 청~녹색 발광다이오드의 개발
이홍찬(Hong-Chan Lee),이상태(Sang-Tae Lee),김윤식(Yoon-Sik Kim) 한국마린엔지니어링학회 2005 한국마린엔지니어링학회 학술대회 논문집 Vol.2005 No.-
Optical characteristics of excitonic blue and green emission of Te-doped ZnSSe:Te epitaxial layers, grown by molecular beam epitaxy, were investigated by photoluminescence (PL) measurements. The Te-doped ternary specimen shows strong blue or green emission (at 300K) which is assigned to Te₁ or Te<SUB>n</SUB> (n≥ 2) cluster cluster bound exciton, respectively. Bright green and blue light emitting diodes (LEDs) have been developed using ZnSSe:Te system as an active layer. The green LEDs exhibit a fairly long device lifetime (>2000 h) when operated at 3 A/㎠ under CW condition at room temperature.
MBE성장에 의한 Ⅱ-Ⅵ/Ⅲ-Ⅴ 헤테로접합 태양전지에 관한 연구
이홍찬(Hong-Chan Lee),이상태(Sang-Tae Lee),안병원(Byong-Won Ahn),박영산(Young-San PArk) 한국마린엔지니어링학회 2003 한국마린엔지니어링학회 학술대회 논문집 Vol.2003 No.-
We report a study of ZnSSe/GaAs heterojunction solar cells grown by molecular beam epitaxy (MBE). ZnSSe/GaAs heterostructures prepared under different conditions were characterized in-situ by reflection high-energy electron diffraction (RHEED). Deep level transient spectroscopy (DL TS) measurements were carried out in the 200-350K temperature range. The point defect density of solar cell (CS#3), which was grown by atomic layer epitaxy (ALE), was very small compared to that of CS#l. Dark and illuminated I-V measurements were performed in order to compare any changes in solar cells. The solar cells (CS#3 and CS#4), which were grown by ALE, showed the improvement of open-circuit voltage (Voc) and conversion efficiency.
MBE법으로 제작한 ZnSe/GaAs 이종접합 태양전지에 관한 연구
이홍찬(Hong-Chan Lee),이상태(Sang-Tae Lee),오진석(Jin-Suck Oh),김윤식(Yoon-Sik Kim),장지호(Jiho Chang) 한국마린엔지니어링학회 2006 한국마린엔지니어링학회 학술대회 논문집 Vol.2006 No.-
We report a study of Zn(S)Se/GaAs heterojunction solar cells grown by molecular beam epitaxy (MBE). Zn(S)Se/GaAs heterostructures prepared under different conditions were characterized in-situ by reflection high-energy electron diffraction (RHEED). Structural and electrical properties were investigated with double crystal X-ray diffraction and current-voltage characteristics, respectively. The fabricated n-ZnS<SUB>0.07</SUB>Se<SUB>0.93</SUB>/p-GaAs solar cell (SC #2) exhibited open circuit voltage(V<SUB>∝</SUB>) of 0.37 V, short circuit current(I<SUB>sc</SUB> of 1.7×10?² ㎃, fill factor of 0.62 and conversion efficiency of 7.8 % under 38.5 ㎽/㎠ illumination.