• 대한전기학회:학술대회논문집
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• 대한전기학회 2006년도 심포지엄 논문집 정보 및 제어부문
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• pp.135-137
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• 2006

To improve device yield and throughput, faults in plasma processing equipment should be quickly and accurately diagnosed. Despite many useful information of ex-situ sensor measurements, their applications to recognize plasma faultshave not been investigated. In this study, a new technique to identify fault causes by recognizing X-ray photoelectron spectroscopy (XPS) using neural network and continuous wavelet transformation (CWT). The presented technique was evaluated with the plasma etch data. A totalof 17 experiments were conducted for model construction. Model performance was investigated from the perspectives of training error, testing error, and recognition accuracy with respect to various thresholds. CWT-based BPNN models demonstrated a higher prediction accuracy of about 26%. Their advantages over pure XPS-based models were conspicuous in all three measures at small networks.

• 진공이야기
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• 제3권4호
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• pp.8-13
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• 2016

The need of space-resolved x-ray photoelectron spectroscopy (XPS) has developed scanning photoelectron microscopy (SPEM). SPEM provides space-resolved XPS data from a spot of a sample as well as images of specific element, chemical state, valency distribution on the surface of a sample. Based on technical advancement of tight x-ray focusing, sample positioning accuracy, and electron analyzer efficiency, SPEM is now capable of providing ~100 nm space resolution for typical XPS functionality, and SPEM has become actively applied for the investigation of chemical state, valency, and electronic structure on the surface of newly discovered materials, such as graphene layers, dichalcogenide 2D-materials, and heterogenous new functional materials.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2005년도 심포지엄 논문집 정보 및 제어부문
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• pp.281-283
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• 2005

Processing Plasmas are very sensitive to a variation in process parameters, To maintain process quality and device field, plasma malfunction should be tightly monitored with high sensitivity. A new monitoring method is presented and this was accomplished by applying discrete wavelet transformation to X-ray photoelectron spectroscopy. XPS data were collected during a plasma etching of silicon carbide. Various effects of DWT factor on fault sensitivity were optimized experimentally. Compared to raw data, total percent sensitivity for DWT data demonstrated a significantly improved sensitivity to plasma faults induced by bias power.

• 한국표면공학회지
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• 제23권3호
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• pp.183-193
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• 1990

• 한국진공학회:학술대회논문집
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• 한국진공학회 2011년도 제40회 동계학술대회 초록집
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• pp.348-348
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• 2011

We present the interfacial electronic structures of electrodeposited Cu and Fe on bare and 1,4-phenylene diisocyanide (PDI)-functionalized Au nanoisland templates (NITs), and Au and Ag nanoparticles on transition metal oxide supports. Our discussion is based on the depth-profiling X-ray photoelectron spectroscopy (XPS) and scanning electron microscopy (SEM).

• 한국표면공학회지
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• 제29권6호
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• pp.728-734
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• 1996

To obtain the relation in the electrochemical reduction of $CO_2$ in aqueous $KHCO_3$ colution between an activity for the product and the nature of Cu electrode, the electrode surface was characterized by using two methods: X-ray photoelectron spectroscopy (XPS) and photoelectron emission (PE) measurement. Electrolyses were performed with Cu electrodes pretreated in several ways. The distribution of the products changed drastically with electrolysis time and the pretreatment method. The features in XPS spectra were closely connected with the product distribution. The oxide film at the electrode surface was gradually reduced to bare Cu metal with electrolysis time, resulting in a variation of the product distribution. PE was measured by verying the wavelength of incident light at several temperatures. The dependence of PE on the measurement temperature changed greatly before and after electrolysis.

• 진공이야기
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• 제1권1호
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• pp.17-20
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• 2014

This article introduces the basic concepts of various soft X-ray spectroscopies in the study of surface and interface electronic structures. Especially, recent results of X-ray photoelectron spectroscopy experiments on organic/inorganic thin films and a lead-free solder alloys will be discussed. Soft X-ray spectroscopies to understand the chemical and electrical properties would be of broad interest in the vacuum science communities.

• 분석과학
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• 제7권1호
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• pp.115-124
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• 1994

탈지과정을 거친 냉연 강판을 순수로 세정하는 과정에서 발생하는 rust와 이러한 rust 발생을 방지하기 위하여 0.05%(wt) $Na_5P_3O_{10}$ 용액으로 표면처리한 냉연 강판의 표면은 X-ray Photoelectron Spectroscopy(XPS) 방법으로 비교 분석하였다. Rust가 발생한 냉연 강판의 표면은 $Fe_2O_3$ 및 FeO, 그리고 $Fe(OH)_3$등으로 구성되는 산화층이 $1500{\AA}$정도의 두께로 존재함을 알 수 있었고, 한편 $Na_5P_3O_{10}$ 용액으로 표면처리한 냉연 강판의 표면은 $60{\AA}$정도의 인산염 피막이 얇은 Fe 산화층 위에 존재함으로써 보호 피막의 역할을 한다는 것을 알 수 있었다.

• 한국추진공학회:학술대회논문집
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• 한국추진공학회 2017년도 제48회 춘계학술대회논문집
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• pp.168-171
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• 2017

X-ray photoelectron spectroscopy(XPS) 분석법을 이용하여 FKM O-ring의 대기중에서의 노화 메카니즘을 관찰하였다. FKM O-ring은 선경 3.53mm, 내경 91.67mm인 오링을 시편으로 사용하였다. 노화 후 FKM O-ring의 oxygen 원소의 농도가 20.39%로 증가하였으며, fluorine 원소는 각각 8.29%로 감소하는 경향을 나타내었다. 이를 통하여 산소에 의한 산화 반응이 FKM O-ring의 주요 노화 반응으로 나타났다. C1s와 F1s 피크 분석 결과, FKM O-ring의 주쇄중 C-F 결합에서 산화 반응이 주로 진행되는 것으로 나타났다. 또한 O1s 피크 분석 결과, 산화 반응을 통하여 C-OH, C=O, 그리고 O=C-O 구조를 형성하며, 주로 카르복실기가 생성되는 것으로 나타났다.

• 한국전기전자재료학회논문지
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• 제15권6호
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• pp.551-557
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• 2002

Carbon nitride films have been deposited on Si(100) substrate by a high voltage discharge plasma combined with laser ablation in a nitrogen atmosphere. The films were grown both with the without the presence of an assisting focused Nd:YAG laser ablation. The laser ablation of the graphite target leads to vapor plume plasma expending into th ambient nitrogen arc discharge area. X-ray photoelectron spectroscopy and Auger electron spectroscopy were used to identify the binding structure and the content of the nitrogen species in the deposited films. The nitrogen content of the films was found to increase drastically with an increase of nitrogen pressure. The surface morphology of the films was studied using a scanning electron microscopy. Data of infrared spectroscopy and x-ray photoelectron spectroscopy indicate the existence of carbon-nitrogen bonds in the films. The x-ray diffraction measurements have also been taken to characterize the crystal properties of the obtained films.