• Proceedings of the Korean Society of Machine Tool Engineers Conference
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• 2004.10a
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• pp.257-262
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• 2004

As optical connectors dominate the performance of optical transmitters or receivers, they need an ultra-precise processing and are composed of optical fibers, ferrule and optical glass lenses. Therefore, this study suggests a nondestructive evaluation technique or a system using resonant ultrasound spectroscopy to evaluate flaws in a optical glass lens. It also conducted a nondestructive evaluation for flaws that are commonly found in a optical glass lens and reviewed the results.

• Proceedings of the Korean Vacuum Society Conference
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• 2014.02a
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• pp.262.2-262.2
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• 2014

Plasma processing is an essential process for pattern etching and thin film deposition in nanoscale semiconductor device fabrication. It is necessary to maintain plasma chamber in steady-state in production. In this study, we determined plasma chamber state with residual gas analysis with self-plasma optical emission spectroscopy. Residual gas monitoring of fluorocarbon plasma etching chamber was performed with self-plasma optical emission spectroscopy (SPOES) and various chemical elements was identified with a SPOES system which is composed of small inductive coupled plasma chamber for glow discharge and optical emission spectroscopy monitoring system for measuring optical emission. This work demonstrates that chamber state can be monitored with SPOES and this technique can potentially help maintenance in production lines.

• Proceedings of the Korean Vacuum Society Conference
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• 2012.08a
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• pp.153-153
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• 2012

Endpoint detection with plasma impedance monitoring and self-plasma optical emission spectroscopy is demonstrated for dielectric layers etching processes. For in-situ detecting endpoint, optical-emission spectroscopy (OES) is used for in-situ endpoint detection for plasma etching. However, the sensitivity of OES is decreased if polymer is deposited on viewport or the proportion of exposed area on the wafer is too small. To overcome these problems, the endpoint was determined by impedance signal variation from I-V monitoring (VI probe) and self-plasma optical emission spectroscopy. In addition, modified principal component analysis was applied to enhance sensitivity for small area etching. As a result, the sensitivity of this method is increased about twice better than that of OES. From plasma impedance monitoring and self-plasma optical emission spectroscopy, properties of plasma and chamber are analyzed, and real-time endpoint detection is achieved.

• Proceedings of the Optical Society of Korea Conference
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• 1991.07a
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• pp.15-22
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• 1991

The general aspects of Laser Resonance Ionization Spectroscopy (RIS) and its application are investigated. Combination of laser selective photoionization and mass spectrometer as apromising spectroscopic as well as an analytical tool is mainly considered. The application of RIS includes mercury (Hg) atomic spectroscopy, trace analysis of lead (Pb) and resonance enhanced two photon ionization spectroscopy of Cis-hexatriene.

• Proceedings of the Optical Society of Korea Conference
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• 1999.08a
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• pp.182-183
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• 1999

• Proceedings of the Optical Society of Korea Conference
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• 2009.02a
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• pp.443-444
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• 2009

• Publications of The Korean Astronomical Society
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• v.15 no.spc1
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• pp.39-60
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• 2000

We will discuss two-dimmensional spectrophotometry including long-slit spectroscopy and narrow-band imaging. The basic principles, applications, and techniques of observations and data reduction of spectroscopy and spectrophotometry for extended objects are described. This discussion will focus on practical long-slit spectroscopy using a Cassegrain spectrograph attached with 2 or 4m class telescopes and on imaging spectrophotometry using narrow-band interference filter sets. We will discuss scientific applications.

• Proceedings of the Optical Society of Korea Conference
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• 2004.07a
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• pp.46-47
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• 2004

• Journal of the Optical Society of Korea
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• v.5 no.3
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• pp.110-116
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• 2001

Recently observed dark resonance phenomena is solids are reviewed and discussed for potential applications to high-resolution coherence spectroscopy. in an inhomogeneously broadened system, a new type of high-resolution spectroscopy based on electromagnetically induced transparency is demonstrated.

• Journal of the Semiconductor & Display Technology
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• v.17 no.4
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• pp.97-100
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• 2018

$NF_3$ Plasma etching of silicon was conducted by injecting only $NF_3$ gas into reactive ion etching. $NF_3$ Plasma etching was done in intermediate pressure. Silicon etching by $NF_3$ plasma in reactive ion etching was diagnosed through residual gas analyzer and optical emission spectroscopy. In plasma etching, optical emission spectroscopy is generally used to know what kinds of species in plasma. Also, residual gas analyzer is mainly to know the byproducts of etching process. Through experiments, the results of optical emission spectroscopy during silicon etching by $NF_3$ plasma was analyzed with connecting the results of etch rate of silicon and residual gas analyzer. It was confirmed that $NF_3$ plasma etching of silicon in reactive ion etching accords with the characteristic of reactive ion etching.