• 제목/요약/키워드: Single Cell

검색결과 3,845건 처리시간 0.034초

Optimization of the firing process condition for high efficiency solar cells on single-crystalline silicon (고효율 Solar Cell 제조를 위한 Firing 공정 조건의 최적화)

  • Jeong, Se-Won;Lee, Seong-Jun;Hong, Sang-Jin;Han, Seung-Su
    • Proceedings of the Korean Institute of Surface Engineering Conference
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    • 한국표면공학회 2006년도 추계학술발표회 초록집
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    • pp.4-5
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    • 2006
  • This paper represents modeling and optimization techniques for solar cell process on single-crystalline float zone (FZ) wafers with high efficiency; There were the four significant processes : i)emitter formation by diffusion, anti-reflection-coating (ARC) with silicon nitride using plasma-enhanced chemical vapor deposition (PECVD); iii)screen-printing for front and back metallization; and iv)contact formation by firing. In order to increase the performance of solar cells, the contact formation process is modeled and optimized. This paper utilizes the design of experiments (DOE) in contact formation to reduce process time, fabrication costs. The experiments were designed by using central composite design which is composed of $2^4$ factorial design augmented by 8 axial points with three center points. After contact formation process, the efficiency of the solar cell is modeled using neural networks. This model is used to analyse the characteristics of the process, and to optimize the process condition using genetic algorithms (GA). Finally, find optimal recipe for solar cell efficiency.

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A study on characteristics of the scaled SONOSFET NVSM for Flash memory (플래시메모리를 위한 scaled SONOSFET NVSM 의 프로그래밍 조건과 특성에 관한 연구)

  • 박희정;박승진;홍순혁;남동우;서광열
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 한국전기전자재료학회 2000년도 하계학술대회 논문집
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    • pp.751-754
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    • 2000
  • When charge-trap SONOS cells are used flash memory, the tunneling program/erase condition to minimize the generation of interface traps was investigated. SONOSFET NVSM cells were fabricated using 0.35$\mu\textrm{m}$ standard memory cell embedded logic process including the ONO cell process. based on retrograde twin-well, single-poly, single metal CMOS process. The thickness of ONO triple-dielectric for memory cell is tunnel oxide of 24${\AA}$, nitride of 74 ${\AA}$, blocking oxide of 25 ${\AA}$, respectively. The program mode(Vg: 7,8,9 V, Vs/Vd: -3 V, Vb: floating) and the erase mode(Vg: -4,-5,-6 V, Vs/Vd: floating, Vb: 3V) by modified Fowler-Nordheim(MFN) tunneling were used. The proposed programming condition for the flash memory of SONOSFET NVSM cells showed less degradation($\Delta$Vth, S, Gm) characteristics than channel MFN tunneling operation. Also the program inhibit conditions of unselected cell for separated source lines NOR-tyupe flash memory application were investigated. we demonstrated that the program disturb phenomenon did not occur at source/drain voltage of 1 V∼4 V and gate voltage of 0 V∼4.

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A Single-phase PWM Voltage Source Inverter for Photovoltaic Generation System (태양광 발전시스템을 위한 단상 PWM 전압형 인버터)

  • Yoo, Taek-Bin;Sung, Nark-Kuy;Kang, Seung-Wook;Lee, Seung-Hwan;Lee, Hoon-Goo;Han, Kyung-Hee
    • Proceedings of the KIEE Conference
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    • 대한전기학회 1995년도 하계학술대회 논문집 A
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    • pp.443-445
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    • 1995
  • Since the residential load is an AC load, while the output of solar cell is a DC power, the photovoltaic system needs the DC/AC converter to utilize solar cell and must provide the sinusoidal wave current and voltage with unity power factor in the case of driving to Interact with utility line. It is always necessary for the output of solar cell to operate in the vicinity of maximum power point, since it is greatly fluctuated by insolation. This paper treats that we will constitute a single phase PWM voltage source inverter and trace the modulation index which always maximize the output of solar cell in propotion to insolation variation and prove it by simulation that we can provide current wave, which is nearly sinusoidal wave with unity power factor, for load and utility line.

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Analysis of Radiation Dose on Single Cells Using Therapeutic Radioisotopes Using the Monte Carlo Method (몬테카를로 방법을 이용한 치료용 방사성동위원소 사용 시 단일 세포에 대한 선량 분석)

  • Kim, Jung-Hoon;Kim, Yu-Soo
    • Journal of radiological science and technology
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    • 제45권5호
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    • pp.433-438
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    • 2022
  • Targeted radionuclides treatment (TRT) requires the establishment of treatment plans that consider various factors, such as the type of radionuclides, target organs, and administration methods. For this reason, in this study, the absorption dose of a single cell was analyzed according to the type of radioisotope used to treat target radionuclides. In this study, a simulation was performed on beta rays used in the treatment of target radionuclides at the cell level using MCNPX (ver. 2.5.0). First, according to the calculation formula, the beam path according to the type of radioisotope for treatment was calculated. Second, the amount of self-radiation by beta rays emitted from cell diameters of 5 ㎛ and 10 ㎛ cell nuclei was evaluated. As a result, it showed a high range proportional to the maximum energy of the beta-ray, and the highest self-dose distribution from 177 Lu radiation sources among therapeutic radioisotopes. This was analyzed as a result that is inversely proportional to the maximum energy of the beta-ray, and it suggests that the selection of a nuclide considering the range of the beta-ray is necessary in the treatment of target radionuclides in the future.

Transcriptional Heterogeneity of Cellular Senescence in Cancer

  • Junaid, Muhammad;Lee, Aejin;Kim, Jaehyung;Park, Tae Jun;Lim, Su Bin
    • Molecules and Cells
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    • 제45권9호
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    • pp.610-619
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    • 2022
  • Cellular senescence plays a paradoxical role in tumorigenesis through the expression of diverse senescence-associated (SA) secretory phenotypes (SASPs). The heterogeneity of SA gene expression in cancer cells not only promotes cancer stemness but also protects these cells from chemotherapy. Despite the potential correlation between cancer and SA biomarkers, many transcriptional changes across distinct cell populations remain largely unknown. During the past decade, single-cell RNA sequencing (scRNA-seq) technologies have emerged as powerful experimental and analytical tools to dissect such diverse senescence-derived transcriptional changes. Here, we review the recent sequencing efforts that successfully characterized scRNA-seq data obtained from diverse cancer cells and elucidated the role of senescent cells in tumor malignancy. We further highlight the functional implications of SA genes expressed specifically in cancer and stromal cell populations in the tumor microenvironment. Translational research leveraging scRNA-seq profiling of SA genes will facilitate the identification of novel expression patterns underlying cancer susceptibility, providing new therapeutic opportunities in the era of precision medicine.

Comparative Study on the Organic Solvent of IrO2-Ionomer Inks used for Spray Coating of Anode for Proton Exchange Membrane Water Electrolysis

  • Hye Young Jung;Yongseok Jun;Kwan-Young Lee;Hyun S. Park;Sung Ki Cho;Jong Hyun Jang
    • Journal of Electrochemical Science and Technology
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    • 제14권3호
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    • pp.283-292
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    • 2023
  • Currently, spray coating has attracted interest in the mass production of anode catalyst layers for proton exchange membrane water electrolysis (PEMWE). The solvent in the spray ink is a critical factor for the catalyst dispersion in ink, the microstructure of the catalyst layer, and the PEMWE performance. Herein, various pure organic solvents were examined as a substitute for conventional isopropanol-deionized water (IPA-DIW) mixture for ink solvent. Among the polar solvents that exhibited better IrO2 dispersion over nonpolar solvents, 2-butanol (2-BuOH) was selected as a suitable candidate. The PEMWE single cells were fabricated using 2-BuOH at various ionomer contents, spray nozzle types, and drying temperatures, and their performance was compared to the cells fabricated using a conventional IPA-DIW mixture. The PEMWE single cells with 2-BuOH solvent showed good performances comparable to the conventional IPA-DIW mixture case and highly durable performances under accelerated degradation tests.