Fabrication of Cu<SUB>2</SUB>ZnSnS<SUB>4</SUB> Films by Rapid Thermal Annealing of Cu/ZnSn/Cu Precursor Layer and Their Application to Solar Cells

R.B.V. Chalapathy,Gwang Sun Jung,Young Min Ko,Byung Tae Ahn,HyukSang Kwon 한국태양광발전학회 2013 Current Photovoltaic Research Vol.1 No.2

Cu2ZnSnS4 thin film have been fabricated by rapid thermal annealing of dc-sputtered metal precursor with Cu/ZnSn/Cu stack in sulfur ambient. A CZTS film with a good uniformity was formed at 560℃ in 6 min. Cu2SnS3 and Cu3SnS4 secondary phases were present at 540°C and a trace amount of Cu2SnS3 secondary phase was present at 560℃. Single-phase large-grained CZTS film with rough surface was formed at 560ºC. Solar cell with best efficiency of 4.7% (Voc = 632 mV, jsc = 15.8 mA/cm<SUP>2</SUP>, FF = 47.13%) for an area of 0.44cm<SUP>2</SUP> was obtained for the CZTS absorber grown at 560℃ for 6 min. The existence of second phase at lower-temperature annealing and rough surface at higher-temperature annealing caused the degradation of cell performance. Also poor back contact by void formation deteriorated cell performance. The fill factor was below 0.5; it should be increased by minimizing voids at the CZTS/Mo interface. Our results suggest that CZTS absorbers can be grown by rapid thermal annealing of metallic precursors in sulfur ambient for short process times ranging in minutes.

Fabrication of Cu₂ZnSnS₄ Films by Rapid Thermal Annealing of Cu/ZnSn/Cu Precursor Layer and Their Application to Solar Cells

Chalapathy, R.B.V.,Jung, Gwang Sun,Ko, Young Min,Ahn, Byung Tae,Kwon, HyukSang Korea Photovoltaic Society 2013 Current Photovoltaic Research Vol.1 No.2

$Cu_2ZnSnS_4$ thin film have been fabricated by rapid thermal annealing of dc-sputtered metal precursor with Cu/ZnSn/Cu stack in sulfur ambient. A CZTS film with a good uniformity was formed at $560^{\circ}C$ in 6 min. $Cu_2SnS_3$ and $Cu_3SnS_4$ secondary phases were present at $540^{\circ}C$ and a trace amount of $Cu_2SnS_3$ secondary phase was present at $560^{\circ}C$. Single-phase large-grained CZTS film with rough surface was formed at $560^{\circ}C$. Solar cell with best efficiency of 4.7% ($V_{oc}=632mV$, $j_{sc}=15.8mA/cm^2$, FF = 47.13%) for an area of $0.44cm^2$ was obtained for the CZTS absorber grown at $560^{\circ}C$ for 6 min. The existence of second phase at lower-temperature annealing and rough surface at higher-temperature annealing caused the degradation of cell performance. Also poor back contact by void formation deteriorated cell performance. The fill factor was below 0.5; it should be increased by minimizing voids at the CZTS/Mo interface. Our results suggest that CZTS absorbers can be grown by rapid thermal annealing of metallic precursors in sulfur ambient for short process times ranging in minutes.

신장 ; 신기능에 따른 폐외결핵의 임상적 특징과 예후

최보경 ( Bo Kyung Choi ),이희선 ( Hee Sun Lee ),황인혜 ( In Hye Hwang ),신경화 ( Kyung Hwa Shin ),최문기 ( Mun Ki Choi ),최보광 ( Bo Gwang Choi ),안강희 ( Kang Hee Ahn ),남형석 ( Hyung Seok Nam ),황종민 ( Jong Min Hwang ),성은영 ( 대한내과학회 2010 대한내과학회지 Vol.79 No.4

목적: 만성 신질환 환자에서 세포성 면역기능이 감소되어 결핵에 이환될 위험성이 높으며, 특히 폐외결핵의 발생 빈도가 높은 것으로 알려져 있다. 이에 신기능에 따른 폐외결핵의 임상양상, 치료 반응, 질환과 연관된 사망률의 차이점을 비교하였다. 방법: 2003년 1월부터 2007년 12월까지 폐외결핵으로 진단된 18세 이상의 환자를 대상으로 하였고, 진단 당시의 크레아티닌 값을 이용하여 MDRD 공식으로 계산한 추정 사구체 여과율(eGFR)이 60 mL/min/1.73 m2을 기준으로 신기능 장애군(Group I)과 정상 신기능군(Group II)으로 분류하여 폐외결핵의 임상상, 치료성공률, 사망률 및 치료기간의 차이를 후향적 비교 분석하였다. 결과: 총 342명의 환자 중 Group I은 30명으로 이중 투석을 시행하고 있는 환자는 6명이었고, Group II는 312명으로, 각각의 평균 사구체 여과율은 34±19 mL/min/1.73 m2, 102±26 mL/min/1.73 m2이었다. Group I에서 고연령, 빈혈, 저알부민증이 많았으며, 고혈압, 당뇨병 및 심혈관계 질환을 동반한 경우가 많았다. 폐외결핵의 발생 부위는 두 환자군 모두 (Group I vs. Group II)에서 흉막(30.0% vs. 28.2%)이 가장 빈도가 높았고, 신경계통(23.3% vs. 16.3%)과 림프절(16.7% vs. 17.6%)의 감염이 흔하였으나, 통계학적 유의성은 없었다 (p=0.379). 모든 환자들은 표준 결핵화학요법인 HERZ, HER 및 HRZ 등을 용량 조절하여 치료하였으며, 두 환자군 모두에서 치료 실패 및 재발은 없었다. 결핵과 연관된 사망률은 Group I에서 높았으며(Group I, 22.2% vs. Group II, 2.8%, p<0.001), 연령, 혈색소 및 알부민, 당뇨병, 고혈압 및 심혈관계 질환의 유무를 보정하였을 경우에도 Group I이 사망의 위험률이 높았다(HR=11.51, 95%CI 2.512~52.741; p=0.002). 치료 중 이탈된 환자 및 사망환자를 제외하였을 경우, Group I이 치료 기간이 짧았다(278±110일 vs. 367±170일, p=0.009). 결론: 신기능 장애 환자에서 폐외결핵에 대한 치료기간이 연장되지 않았고 사망을 제외한 치료실패와 재발이 없었으나 폐외결핵으로 인한 사망률은 높았고, 신기능 저하 자체가 사망의 독립적인 위험 요소였다. 그러므로 신기능 장애 환자에서 폐외결핵에 대한 적극적인 진단 및 치료가 더 요구된다고 판단한다. Background/Aims: There is an increased risk of tuberculosis (TB) with impaired cellular immunity and extrapulmonary TB is more common in patients with chronic kidney disease. We explored the clinical features and treatment outcomes of extrapulmonary TB according to renal function. Methods: This retrospective study reviewed the medical records of patients diagnosed with extrapulmonary TB between January 2003 and December 2007. We classified the patients into two groups using the glomerular filtration rate (eGFR), estimated using the Modification of Diet in Renal Disease (MDRD) formula cut-off of 60 mL/min/1.73 m2 and evaluated their clinical features, treatment outcome and mortality (Group I vs. Group II, ≥ 60 mL/min/1.73 m2). Results: The mean eGFR of Groups I (n=30) and II (n=312) was 34±19 and 102±26 mL/min/1.73 m2, respectively. The pleura was the most frequent site of TB in both groups (Group I, 30.0% vs. Group II, 28.2%; p=0.379). There was no treatment failure or recurrence in either group. The mortality was higher in Group I (22.2% vs. 2.8%; p<0.01). In a multivariate analysis, eGFR<60 mL/min/1.73 m2 was an independent risk factor for mortality (HR=11.51, CI 2.512-52.741; p=0.002). Conclusions: Mortality related to extrapulmonary TB was higher in patients with impaired kidney function and kidney function was an independent predictor. However, there was no difference in treatment failure and recurrence according to renal function. (Korean J Med 79:387-393, 2010)

Introduction of Precise Nuclear Measurements and Geostandards

Gwang-Min Sun,Young Rang Uhm,Jaegi Lee 한국자기학회 2021 한국자기학회 학술연구발표회 논문개요집 Vol.31 No.1

Recently, as the use of analytical instruments increases, researches are actively conducted to improve the accuracy and precision of the analysis results. In particular, geostandards are used in many aspects such as deducting calibration curves in geochemical analysis and determining deviations by comparison with true values. In Korea, studies on the development and production of geostandards have been attempted with increasing demand for Korean geostandard materials, but subsequent work has not been carried out. Currently, research institutes that support the quantitative analysis are using geostandards from foreign research institute like USGS, NIST and GSJ etc. However, due to the disadvantage that it is expensive and difficult to obtain, it is necessary to develop a geostandards using Korean rocks. In this study, we selected three representative granite and obsidian samples and checked the feasibility of developments as a Korean geostandards. Moreover, in order to make a glass geostandard, natural glass rock is used for X-ray fluorescence analysis, Neutron Activation Analysis, and Mössbauer spectroscopy then we will examine the feasibility as a glass geostandards. Glass geostandards are essentially used to precision geochemical analyzers. Further, in order to overcome the limitation in the composition range of the geostandards, it is required to prepare a glass geostandards having a higher composition. In order to minimize the inhomogeneity from the microlites contained in the glassy rocks and the incomplete melting, we conducted the XRF and the Prompt gamma - ray Activation Analysis using the obsidians from Mt. Beakdu, Korea and the Kyushu, Japan, which are the main provinces of the obsidian artifacts excavated from the Korean Peninsula. And then we performed comparison with two analytical data from two different methods. The correlations of the major oxide contents show relative good coincidence between the PGAA and XRF bulk analytical data. Also, in mineralogical and geochemical studies on the Mt. Beakdu, Korea and the Kyushu, Japan, obsidians, the origination of the magma compositions and the crystallization as shown in analyses of Mössbauer spectra.

An investigation of excretion of calcium from female mice ingested with boron by using neutron activation analysis

Sun, Gwang Min,Lee, Jaegi,Uhm, Young Rang,Baek, Hani Korean Nuclear Society 2020 Nuclear Engineering and Technology Vol.52 No.11

Boron has been considered to play a nutritionally important role in humans and animals, but its biochemical functions are not clearly understood. Though there are signs that boron affects the mineral and hormone metabolisms, there is no comprehensive epidemiological evidence establishing a relationship between a boron intake and osteoporosis due to the excretion of calcium in the bones. In this study, we investigated the influence of boron intake on the calcium excretion of old female mice in the menopause. The concentrations of calcium in backbone, thigh bone, blood, kidney, liver, and spleen were investigated by using instrumental neutron activation analysis.

Solar Neutrino Detection Technology As a Probe to the Inner Structure of Heavenly Body

Gwang-Min Sun,Bo Young Han 한국자기학회 2015 한국자기학회 학술연구발표회 논문개요집 Vol.2015 No.11

Modelling and Diagnosis of Wooden Cultural Heritages for the Radiation Processing

Gwang Min Sun 한국자기학회 2018 한국자기학회 학술연구발표회 논문개요집 Vol.2018 No.3

Quantification of Nb and Zr in the irradiated pressure tubes from Wolsong CANDU Unit 1 by neutron activation analysis

Sun, Gwang Min,Cho, Dong Keun Springer-Verlag 2013 Journal of radioanalytical and nuclear chemistry Vol.296 No.2

Performance of a Compton Suppression Spectrometer of the SNU-KAERI PGAA Facility

Sun Gwang Min,Park Chang Su,Choi H.D. Korean Nuclear Society 2003 Nuclear Engineering and Technology Vol.35 No.4

The \gamma-ray spectrometer of the PGAA (Prompt Gamma Activation Analysis) facility constructed at HANARO of the Korea Atomic Energy Research Institute was upgraded to the multi-mode spectrometer including the single mode, the Compton suppression mode and the pair mode. The performance of the spectrometer was tested and summarized. The background count rate and the uncertainty of the detection efficiency were reduced greatly in comparison with those before the new installation.

해수산 무지개송어(Oncorhynchus mykiss) 프레임 육포의 위생적 및 영양적 특성

김민우 ( Min Woo Kim ),김용중 ( Yong Jung Kim ),김민주 ( Min Joo Kim ),이수광 ( Su Gwang Lee ),박선영 ( Sun Young Park ),최병대 ( Byeong Dae Choi ),허민수 ( Min Soo Heu ),김진수 ( Jin Soo Kim ) 한국수산과학회(구 한국수산학회) 2016 한국수산과학회지 Vol.49 No.3

Large quantities of by-products-such as fish frame, head, skin and viscera-are generated during seafood processing, and these by-products are not utilized extensively. Therefore, sea rainbow trout Oncorhynchus mykiss (SRT) frame muscle (FM) jerky was prepared by grinding SRT-FM, followed by mixing with seasoning, forming and drying. The nutritional and microbiological characteristics of the SRT-FM jerky were then investigated. The proximate composition of the SRT-FM jerky was 19.1% moisture, 38.7% crude protein, 7.9% crude lipid and 4.4% ash. The viable bacterium count of the SRT-FM jerky was 3.9 log CFU/g, and Escherichia coli and Staphylococcus aureus were not detected. The total amino acid content of SRT-FM jerky was 37.3 g/100 g, and the major amino acids were aspartic acid, glutamic acid, leucine and lysine. Based on the recommended daily intake of fish jerky (100 g), the most abundant mineral was potassium. The fatty acid composition of the SRT-FM jerky was 26.2% saturated acid, 34.5% monoenoic acid and 39.3% polyenoic acid, and the major fatty acids were 16:0, 18:1n-9, 18:2n-6, 20:5n-3 and 22:6n-3. These results suggest that SRT-FM jerky has high nutritional value.