• 제목/요약/키워드: Emission spectroscopy

검색결과 1,166건 처리시간 0.022초

Revealing ionized gas kinematics at the center of nearby Seyfert galaxies

  • Kim, Eun Chong;Woo, Jong-Hak
    • 천문학회보
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    • 제39권1호
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    • pp.43.2-43.2
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    • 2014
  • We investigate the ionized gas kinematics at the center of 6 nearby Seyfert galaxies, using the integral field spectroscopy data from the Calar Alto Legacy Integral Field spectroscopy Area survey Data Release 1. To understand the kinematic nature of the ionized gas in the narrow-line regions (NLRs), we measured the flux, velocity, and velocity dispersion of the [OIII] $5007{\AA}$ and Ha $6563{\AA}$ emission lines, after subtracting a best-fit stellar population model representing the stellar features. At the same time, we measured stellar velocity as a reference for the systemic velocity, and stellar velocity dispersion. We spatially resolved the velocity structure of the ionized gas using each emission line and compared it to that of stars. In this poster we present the flux, velocity, and velocity dispersion maps of the ionized gas and stars, and discuss the nature of the ionized gas outflows in the central kiloparsec scale.

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플라즈마 공정 감시를 위한 Actinometric 광방사분광기 정보의 신경망 모델링 (Neural Network Modeling of Actinometric Optical Emission Spectroscopy Information for Mo nitoring Plasma Process)

  • 권상희;황보광;이규상;우형수;김병환
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 2007년도 심포지엄 논문집 정보 및 제어부문
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    • pp.177-178
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    • 2007
  • 플라즈마 공정은 집적회로 제작을 위한 미세 박막의 증착과 패턴닝에 핵심적으로 이용되고 있다. 본 연구에서는 플라즈마공정감시와 제어에 응용될 수 있는 모델을 제안한다. 본 모델은 광방사분광기 (Optical emission spectroscopy-OES)정보와 역전파 신경망을 이용해서 개발하였다. 제안된 기법은 Oxide 식각공정에서 수집한 데이터에 적용하였으며, 체계적인 모델링을 위해 공정데이터는 통계적 실험계획법을 적용하여 수집되었다. Raw OES 정보대신, Actinometric OES 정보를 이용하였으며, 신경망의 예측성능은 유전자 알고리즘을 이용해서 증진시켰다. OES의 차수를 줄이기 위해 주인자 분석 (Principal Component Analysis-PCA)을 세 종류의 분산(100, 99, 98%)에 대해서 적용하였다. 최적화한 모델의 예측에러는 323 $\AA/min$이었다. 이전에 PCA를 적용하고 은닉층 뉴런의 함수로 최적화한 모델의 예측에러는 570 $\AA/min$이었으며, 개발된 모델은 이에 비해 43% 증진된 예측 성능을 보이고 있다.

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Fourier Transform 분광기를 이용한 불안정한 분자의 방출분광학 (Emission Spectroscopy of Unstable Molecules using a Fourier Transform Spectrometer)

  • 이상국;김은식
    • 대한화학회지
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    • 제37권4호
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    • pp.371-377
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    • 1993
  • 불안정한 분자의 방출분광학에 상요이 가능하도록 Fourier Transform 분광기를 변형시켰다. 불안정한 분자 라디칼 $CH_3S$는 고전압 직류 방전에 의한 supersonic expansion 속에서 jet 형태의 흐름으로 생성되었다. Supersonic expansion에 의하여 냉각된 라디칼의 형광 스펙트럼은 Fourier Transform UV/VIS 분광기에 의해서 얻어졌다. 스펙트럼의 signal/noise 비율은 증가하였으며, 분자 라디칼 $CH_3S$의 회전구조도 명확하게 볼 수 있었다.

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교류 펄스 전압을 이용한 평판형 대기압 유전격벽방전 플라즈마의 특성 분석 (A Study on the Dielectric Barrier Discharges Plasmas of Flat Atmospheric Pressure Using an AC Pulse Voltage)

  • 이종봉;하창승;김동현;이호준;이해준
    • 전기학회논문지
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    • 제61권5호
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    • pp.717-720
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    • 2012
  • Various types of dielectric-barrier-discharge (DBD) devices have been developed for diverse applications for the last decade. In this study, a flat non-thermal DBD micro plasma source under atmospheric pressure has been developed. The flat-panel type plasma is generated by bipolar pulse voltages, and driving gas is air. In this study, the plasma source was investigated with intensified charge coupled device (ICCD) images and Optical Emission Spectroscopy (OES). The micro discharges are generated on the crossed electrodes. For theoretical analysis, 2-dimensional fluid simulation was performed. The plasma source can be driven in air, and thus the operation cost is low and the range of application is wide.

A Study on Pumping Effect of Oxygen in Polysilicon Gate Etching

  • Kim, Nam-Hoon;Shin, Sung-Wook;Bin, Shin-Seok;Yu chang-Il kim;Chang, Eui-Goo
    • Transactions on Electrical and Electronic Materials
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    • 제1권2호
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    • pp.1-6
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    • 2000
  • This article presents the experiments and considerations possible about gate etching in polysilicon when oxygen gas is added in chamber, We propose the novel study with optical emission spectroscopy in polysilicon etching. It is shown that added oxygen gases play an important role in enhencement of density in chlorine gases as a scavenger of silicon from SiCl$\_$x/. And a small amount of Si-O bonds are deposited and then the deposited thin film protect silicon dioxyde against reaction chlorine with silicon in SiO$_2$. Consequently, we can improve the selectivity of polysilicon the silicon dioxide, which is clearly explained in this model.

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반응성 증착용 펄스 플라즈마 공정의 진단 (A Diagnostic Study of Pulsed Plasma Process for Reactive Deposition)

  • 주정훈
    • 한국표면공학회지
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    • 제45권4호
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    • pp.168-173
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    • 2012
  • A real-time monitoring of an immersed antenna type inductively coupled plasma (ICP) was done with optical emission spectroscopy (OES) to check the reports that sputtered atom density is decreasing as the ICP power is increased. At 10 mTorr pressure of Ar, Mg was sputtered by a bipolar pulsed power supply into 2 MHz ICP which has an insulator covered 2.5 turn antenna. Emitted light was collected in two different positions: above the target and inside the ICP region. With 100 W of Mg sputtering power, the intensities of Mg I (285.06 nm), Mg II (279.48 nm), Ar I (420.1 nm) were increased constantly with ICP power from 100 W to 600 W. At 500 W, the intensity of $Mg^+$ exceeded that of Mg under PID controlled discharge voltage of 180 V. The ratio of Mg II/Mg I was increased from 0.45 to 2.71 approximately 6 times.

The Application of Time-Resolved Laser Induced Fluorescence Spectroscopy in the Complexation Studies of Eu(III) and Cm(III) with Humic Substances

  • Joong Gill Choi;Oum Ka Won;Chang Yeoul Choi;Hichung Moon;Hyun Sang Shin;Park, Seung Min;Paul Joe Chong
    • Bulletin of the Korean Chemical Society
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    • 제14권1호
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    • pp.72-78
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    • 1993
  • The application of time-resolved laser induced fluorescence spectroscopy (TRLIF) to the complexation studies of Eu(III) and Cm(III) with humic substances is described. Using this method, three different spectroscopic characteristics(excitation spectra, emission spectra, and lifetimes) of these aquo ions and their complexes can be directly measured. By observing shifts in the wavelength and changes in the lifetime and intensities of the fluorescence emission, the information on the complexation behavior of humic substances with these trivalent metal cations in an aqueous solution, as well as energy transfer mechanisms, can be obtained. In addition, this method allows precise spectroscopic quantification of the complexation processes at very low concentrations of both components.

준지도학습 기반 반도체 공정 이상 상태 감지 및 분류 (Semi-Supervised Learning for Fault Detection and Classification of Plasma Etch Equipment)

  • 이용호;최정은;홍상진
    • 반도체디스플레이기술학회지
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    • 제19권4호
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    • pp.121-125
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    • 2020
  • With miniaturization of semiconductor, the manufacturing process become more complex, and undetected small changes in the state of the equipment have unexpectedly changed the process results. Fault detection classification (FDC) system that conducts more active data analysis is feasible to achieve more precise manufacturing process control with advanced machine learning method. However, applying machine learning, especially in supervised learning criteria, requires an arduous data labeling process for the construction of machine learning data. In this paper, we propose a semi-supervised learning to minimize the data labeling work for the data preprocessing. We employed equipment status variable identification (SVID) data and optical emission spectroscopy data (OES) in silicon etch with SF6/O2/Ar gas mixture, and the result shows as high as 95.2% of labeling accuracy with the suggested semi-supervised learning algorithm.

플라즈마 정보인자 기반 가상계측을 통한 Si 식각률의 첫 장 효과 분석 (Analysis of First Wafer Effect for Si Etch Rate with Plasma Information Based Virtual Metrology)

  • 유상원;권지원
    • 반도체디스플레이기술학회지
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    • 제20권4호
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    • pp.146-150
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    • 2021
  • Plasma information based virtual metrology (PI-VM) that predicts wafer-to-wafer etch rate variation after wet cleaning of plasma facing parts was developed. As input parameters, plasma information (PI) variables such as electron temperature, fluorine density and hydrogen density were extracted from optical emission spectroscopy (OES) data for etch plasma. The PI-VM model was trained by stepwise variable selection method and multi-linear regression method. The expected etch rate by PI-VM showed high correlation coefficient with measured etch rate from SEM image analysis. The PI-VM model revealed that the root cause of etch rate variation after the wet cleaning was desorption of hydrogen from the cleaned parts as hydrogen combined with fluorine and decreased etchant density and etch rate.

Green Synthesis of Dual Emission Nitrogen-Rich Carbon Dot and Its Use in Ag+ Ion and EDTA Sensing

  • Le Thuy Hoa;Jin Suk Chung;Seung Hyun Hur
    • Korean Chemical Engineering Research
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    • 제61권3호
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    • pp.463-471
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    • 2023
  • Nitrogen-rich carbon dots (NDots) were synthesized by using uric acid as carbon and nitrogen sources. The as-synthesized NDots showed strong dual emissions at 420 nm and 510 nm with excitation at 350 nm and 460 nm, respectively. The physicochemical analyses such as X-ray photoelectron spectroscopy, Transmission electron microscopy and Fourier transform infrared spectroscopy were used to analyze the chemical, physical and morphological structures of NDots. The as-synthesized NDots exhibited wide linear range (0-100 µM) and very low detection limit (124 nM) in Ag+ ion sensing. In addition, Ag+ saturated NDots could be used as an EDTA sensor by the EDTA induced PL recovery.