http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.
변환된 중국어를 복사하여 사용하시면 됩니다.
Chaehwan Jeong,Seongjae Boo,Ho-Sung Kim,Duck-Rye Chang,Minsung Jeon,Koichi Kamisako 한국물리학회 2008 THE JOURNAL OF THE KOREAN PHYSICAL SOCIETY Vol.53 No.1
The effect of the etching gas ratio (Cl2/Ar) and the RF chuck power for dry etching of deposited aluminum-doped zinc oxide (AZO) films was investigated. The initially smooth films showed optical transparencies (T ≥ 80 %) and electrical properties (ρ = 1.14 × 10-3 Ωcm). The etch rate increased gradually with higher RF chuck power and Cl2 gas ratio, reaching a value of ~1450 Å/min. The surface morphology, electrical properties and diffuse reflectance were examined in the etched samples. Heterojunction solar cells with a AZO/p-a-SiC:H/c-Si/Al structure simulated on a textured AZO film show the higher short-circuit current (15.8 mA/㎠) and a higher quantum efficiency (75 %) in the wavelength range of 400 ~ 1100 nm, demonstrating effective light trapping. These results show the potential of a textured layer etched by using ICP etching for solar cell applications. The effect of the etching gas ratio (Cl2/Ar) and the RF chuck power for dry etching of deposited aluminum-doped zinc oxide (AZO) films was investigated. The initially smooth films showed optical transparencies (T ≥ 80 %) and electrical properties (ρ = 1.14 × 10-3 Ωcm). The etch rate increased gradually with higher RF chuck power and Cl2 gas ratio, reaching a value of ~1450 Å/min. The surface morphology, electrical properties and diffuse reflectance were examined in the etched samples. Heterojunction solar cells with a AZO/p-a-SiC:H/c-Si/Al structure simulated on a textured AZO film show the higher short-circuit current (15.8 mA/㎠) and a higher quantum efficiency (75 %) in the wavelength range of 400 ~ 1100 nm, demonstrating effective light trapping. These results show the potential of a textured layer etched by using ICP etching for solar cell applications.
Watekar, Pramod R.,Ju, Seongmin,Boo, Seongjae,Han, Won-Taek Elsevier 2005 Journal of non-crystalline solids Vol.351 No.30
<P><B>Abstract</B></P><P>We report the investigations of the Yb/Tm co-doped alumino-silicate glass prepared with the sol–gel method for the linear and non-linear optical characteristics. The tetraethoxysilane (TEOS) along with other dopants in appropriate proportion were used to obtain the transparent glass with 0.65mm thickness. The measured absorbance was used to calculate the Judd–Ofelt parameters. The emission and absorption cross-sections were calculated from the experimental measurements. The glass showed the emission around 1060nm and 1470nm after pumping with 980nm, confirming the energy transfer from Yb ions to Tm ions in the silica glass. We are the first to report the Yb/Tm co-doping in the bulk silicate glass.</P>
Ju, Seongmin,Linganna, Kadathala,Kim, Bok Hyeon,Boo, Seongjae,An, Yong Ho,Han, Won-Taek American Scientific Publishers 2018 Journal of Nanoscience and Nanotechnology Vol.18 No.3
<P>Alumino-germano-silicate glass optical fiber incorporated with Gd2O3 nano-particles (NPs) was developed by using the modified chemical vapor deposition and the drawing process. The formation of spherical Gd2O3 NPs in the fiber core with average diameter of 10.8 nm was confirmed by the TEM. The distinct absorption peaks in the fiber preform appearing in the UV region at 205, 247, 253, 274, and 312 nm were due to the incorporated Gd2O3 NPs via reorganization of the seven 4f electrons into various multiplets of Gd ions. In the case of the optical fiber obtained by drawing of the preform at high temperature about 2150 degrees C, absorption peaks due to Gd2O3 NPs were found to appear at 383 and 455 nm, which were red-shifted from 274 and 312 nm of the preform, respectively, and it may be due to increase in the size of Gd2O3 NPs after the drawing process. To investigate the photoluminescence (PL) property for UV sensor applications, the PL of the fiber was obtained by illumination of the Xenon-lamp. A PL band appeared in the wavelength band from 370 nm to 450 nm, centering at about 400 nm, which can be attributed to the presence of Gd2O3 NPs embedded in the fiber core. It was also found that the PL intensity at 400 nm showed linear dependence with the excitation power from 0 to 400 W.</P>
Kim, Bok Hyeon,Son, Dong Hoon,Ju, Seongmin,Jeong, Chaehwan,Boo, Seongjae,Kim, Cheol Jin,Han, Won-Taek American Scientific Publishers 2006 Journal of Nanoscience and Nanotechnology Vol.6 No.11
<P>The effect of aluminum incorporation on silver metal quantum dots formation in the alumino-silicate glass film processed by sol-gel process was investigated. The sol-gel derived glass was coated onto the silica glass plate by spin coating with the mixture solution of tetraethyl orthosilicate (TEOS), C2H5OH, H2O, AgNO3, Al(NO3)3·9H2O, and HNO3 with the molar ratios of Ag/Si = 0.12 and Al/Si varying from 0 to 0.12. The formation of the silver metal quantum dots was confirmed by the measurements of the UV/VISoptical spectra, the X-ray diffraction patterns, and the transmission electron microscope images. While the radius of silver metal quantum dots increased with the increase of aluminum concentration, the concentration of the silver metal quantum dots decreased. The formation of the silver metal quantum dots was found strongly suppressed by incorporation of aluminum ions in the glass. The change in the glass structure due to the aluminum incorporation was investigated by the analysis of the Raman spectra. The silver ions in the glass contributed to form stable (Al:Ag)O4 tetrahedra by pairing with aluminum ions and thus clustering of silver metal quantum dots was hindered.</P>
정혜정(Jeong, Hyejeong),오광환(Oh, Kwang H.),이종호(Lee, Jong Ho),부성재(Boo, Seongjae) 한국신재생에너지학회 2010 한국신재생에너지학회 학술대회논문집 Vol.2010 No.06
We studied the fabrication of polycrystalline silicon (pc-Si) films as seed layers for application of pc-Si thin film solar cells, in which amorphous silicon (a-Si) films in a structure of glass/Al/Al₂O₃/a-Si are crystallized by the aluminum-induced layer exchange (ALILE) process. The properties of pc-Si films formed by the ALILE process are strongly determined by the oxide layer as well as the various process parameters like annealing temperature, time, etc. In this study, the effects of the oxide film thickness on the crystallization of a-Si in the ALILE process, where the thickness of Al₂O₃ layer was varied from 4 to 50 nm. For preparation of the experimental film structure, aluminum (~300 nm thickness) and a-Si (~300 nm thickness) layers were deposited using DC sputtering and PECVD method, respectively, and Al₂O₃ layer with the various thicknesses by RF sputtering. The crystallization of a-Si was then carried out by the thermal annealing process using a furnace with the in-situ microscope. The characteristics of the produced pc-Si films were analyzed by optical microscope (OM), scanning electron microscope (SEM), Raman spectrometer, and X-ray diffractometer (XRD). As results, the crystallinity was exponentially decayed with the increase of Al₂O₃ thickness and the grain size showed the similar tendency. The maximum pc-Si grain size fabricated by ALILE process was about 45{mu}m at the Al₂O₃ layer thickness of 4 nm. The preferential crystal orientation was <111> and more dominant with the thinner Al₂O₃ layer. In summary, we obtained a pc-Si film not only with {sim}45{mu}m grain size but also with the crystallinity of about 75% at 4 nm Al₂O₃ layer thickness by ALILE process with the structure of a glass/Al/Al₂O₃/a-Si.
다결정 실리콘 태양전지 제조를 위한 비정질 알루미늄 유도 결정 입자 특성
정혜정(Jeong, Hyejeong),김호성(Kim, Ho-Sung),이호재(Lee, Ho-Jae),부성재(Boo, Seongjae) 한국신재생에너지학회 2010 한국신재생에너지학회 학술대회논문집 Vol.2010 No.11
본 연구에서는 증착법에 의해 제조된 다결정 실리콘을 이용한 태양전지 제작과 관련하여 다결정 실리콘 씨앗층 제조를 위한 기판에 대하여 연구를 수행하였다. 다결정 실리콘 씨앗층을 제조할 수 있는 기술중 aluminum-induced layer exchange(ALILE) 공정을 이용하여 다결정 실리콘 씨앗층을 제조하였다. glass/Al/oxide/a-Si 구조로 알루미늄과 비정질 실리콘 계면에 알루미늄 산화막을 다양한 두께로 형성시켜, 알루미늄 유도 결정화에서 산화막의 두께가 결정화 특성에 미치는 영향, 결정결함, 결정크기에 대하여 연구하였다. 형성된 다결정 실리콘 씨앗층 막의 특성은 OM, SEM, FIB, EDS, Raman spectroscopy, XRD, EBSD 을 이용하여 분석하였다. 그 결과 산화막의 두께가 증가할수록 결함도 함께 증가하였다. 16nm 두께의 산화막 구조에서 <111> 방향의 우선배향성을 가진, 10{mu}m의 sub-grain 결정립을 갖는 씨앗층을 제조 하였다.
Jeong, Seongmook,Ju, Seongmin,Kim, Youngwoong,Jeong, Hyejeong,Boo, Seongjae,Han, Won-Taek American Scientific Publishers 2016 Journal of Nanoscience and Nanotechnology Vol.16 No.6
<P>The germano-silicate optical fiber incorporated with Ge nanoparticles with enhanced optical nonlinearity was developed by using modified chemical vapor deposition and drawing processes. A broad photoluminescence band obtained by pumping with the 404 nm superluminescent diode was found to appear from 540 nm to 1,000 nm. The non-resonant nonlinear refractive index, n(2), of the fiber measured by the continuous wave self-phase modulation method was 4.95 x 10(-20) m(2)/W due to the incorporated Ge nanoparticles in the fiber core. The enhancement of the non-resonant optical nonlinearity may be due to the creation of the NBOs and other defects from the incorporated Ge-NPs in the fiber core.</P>
Fabrication and Optical Characteristics of a Novel Optical Fiber Doped with the Au Nanoparticles
Ju, Seongmin,Nguyen, Viet Linh,Watekar, Pramod R.,Kim, Bok Hyeon,Jeong, Chaehwan,Boo, Seongjae,Kim, Cheol Jin,Han, Won-Taek American Scientific Publishers 2006 Journal of Nanoscience and Nanotechnology Vol.6 No.11
<P>Optical fibers containing gold metal nanoparticles were developed by modified chemical vapor deposition, in which Au(OH)3 and tetraethyl-orthosilicate (TEOS) was used via sol-gel process to incorporate gold metals by providing the reduction atmosphere. The absorption peak appeared near 490 nm was found to be due to the surface plasmon resonance of the gold nanoparticles incorporated in the fiber core.</P>
오광환(Oh, Kwang H.),정혜정(Jeong, Hyejeong),지은옥(Chi, Eun-Ok),김지찬(Kim, Ji Chan),부성재(Boo, Seongjae) 한국신재생에너지학회 2010 한국신재생에너지학회 학술대회논문집 Vol.2010 No.06
Aluminum-induced crystallization (AIC) of amorphous silicon (a-Si) is studied with the structure of a glass/Al/SiO₂/a-Si, in which the SiO₂ layer has micron-sized laser holes in the stack. An oxide layer between aluminum and a-Si thin films plays a significant role in the metal-induced crystallization (MIC) process determining the properties such as grain size and preferential orientation. In our case, the crystallization of a-Si is carried out only through the key hole because the SiO₂ layer is substantially thick enough to prevent a-Si from contacting aluminum. The crystal growth is successfully realized toward the only vertical direction, resulting a crystalline silicon grain with a size of 3{sim}4{mu}m under the hole. Lateral growth seems to be not occurred. For the AIC experiment, the glass/Al/SiO₂/a-Si stacks were prepared where an Al layer was deposited on glass substrate by DC sputter, SiO₂ and a-Si films by PECVD method, respectively. Prior to the a-Si deposition, a 30{times}30 micron-sized hole array with a diameter of 1{sim}2{mu}m was fabricated utilizing the femtosecond laser pulses to induce the AIC process through the key holes and the prepared workpieces were annealed in a thermal chamber for 2 hours. After heat treatment, the surface morphology, grain size, and crystal orientation of the polycrystalline silicon (pc-Si) film were evaluated by scanning electron microscope, transmission electron microscope, and energy dispersive spectrometer. In conclusion, we observed that the vertical crystal growth was occurred in the case of the crystallization of a-Si with aluminum by the MIC process in a small area. The pc-Si grain grew under the key hole up to a size of 3{sim}4{mu}m with the workpiece.