• Journal of the Korean institute of surface engineering
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• v.32 no.3
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• pp.385-388
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• 1999

Electron field emission properties from various CVD diamond films were studied. Diamond films were synthesized by microwave plasma CVD at 1173K and at 673K substrates temperature and pulse microwave plasma CVD at 1173K. B-doped diamond film was synthesized by microwave plasma CVD at 1173K also. Estimation by SEM, both the non-doped diamond film and B-doped diamond film which were synthesized at 1173K substrate temperature were $2~3\mu\textrm{m}$ in diameter and nucleation densities were $10^{8}{\;}numbers/\textrm{cm}^2$ order. The diamond film synthesized at 673K was $0.2\mu\textrm{m}$ in diameter and nucleation densities was 109 numbers/cm2 order. The diamond film synthesized by pulse microwave plasma CVD at 1173K was $0.2\mu\textrm{m}$ in diameter and nucleation density was $10^{9}{\;}numbers/\textrm{cm}^2$ order either. From the result of electron field emission measurement, electron field emission at $20V/\mu\textrm{m}$ from CVD diamond film synthesized by pulse microwave plasma CVD was $37.3\mu\textrm{A}/\textrm{cm}^2$ and the diamond film showed the best field emission property comparison with other CVD diamond.

• The Korean Journal of Ceramics
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• v.2 no.4
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• pp.212-215
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• 1996

This paper focuses the strength and wear resistance of CVD diamond films. The strength of free-standing CVD diamond films synthesized by microwave plasm CVD, DC plasma CVD, RF plasma CVD and arc discharge plasma jet CVD has been measured by three-point bending test. The wear resistance of CVD diamod films has been evaluated by the pin-on-disk type testing. diamond films coated on the base of sintered tungsten carbide pin by hot filament CVD have been rubbed with a sintered diamond disk in muddy water. Volume removed wear of CVD diamond has been compared with stellite, WC alloy and bearing steel.

• Proceedings of the KIPE Conference
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• 2014.07a
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• pp.95-96
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• 2014

450mm 반도체 CVD 장비 개발 및 300mm F-CVD (Flowable CVD) 공정 개발에 있어서 공정 마진 확보 및 막질 품질 개선을 위해 주파수 가변형 RF Generator가 필수적으로 요구되고 있다. 20nm이하 STI (Shallow Trench Isolation), PMD (Pre-metal Dielectric) & IMD (Inter-Metal Dielectric) 미세공정 gap fill에 많은 문제점이 도출되고 있으며, 이유로는 Generator 고정 주파수에서 Matching Time delay 또는 Shooting에 의한 산포의 한계로 파악되었으며, 주파수 가변에 의한 고속 Tune 기능이 요구되어진다. 따라서 400kHz 주파수 가변형 RF-Generator 개발을 진행하였으며 본 논문을 통해 개발되어진 장비의 성능과 시험 평가한 결과를 소개하고자 한다.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.16 no.5
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• pp.40-46
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• 2017

A plasma gas control apparatus for semiconductor plasma etching processes securely holds a cathode for forming a plasma, confines the plasma during the plasma etching process, and discharges gas after etching. It is a key part of the etching process. With the advancement of semiconductor technology, there is increasing interest in parts for semiconductor manufacturing that directly affect wafers. Accordingly, in order to replace the plasma gas control device with a CVD-SiC material superior in mechanical properties to existing SiCs (Sintered-SiC, RB-SiC), a study on the grinding characteristics of CVD-SiC was carried out. It is confirmed that the optimal grinding condition was obtained when the result table feed rate was 2 m/min and the infeed depth was $5{\mu}m$.

• Vacuum Magazine
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• v.2 no.4
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• pp.16-26
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• 2015

Carbon nanomaterials including nanocrystalline diamond and graphene films are expected to play a core role in $21^{st}$ century industries due to their amazing physicochemical properties. To achieve their practical utilization and industrialization, the development of their mass production technologies is strongly required. Recently, a surface wave excited plasma (SWP) which is produced using microwaves has been attracting special attentions as a candidate for the mass production technology of carbon nanomaterials. SWP can allow a low-temperature large-area plasma chemical vapor deposition (CVD) system. Here, this article introduces the promising SWP-CVD technology. Plasma characteristics in a SWP will be introduced in detail to help understanding how to use and control a SWP as a plasma source for CVD applications.

• Proceedings of the KIEE Conference
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• 1997.07d
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• pp.1270-1273
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• 1997

We have investigated the latchup characteristics of BL/BILLI retrograde twin well CMOS that has the high energy ion implanted buried layer to intend for more improvement of latchup compare to conventional retrograde well and BILLI structures. We explored the dependence of various latchup characteristics such as n+ trigger latchup and p+ trigger latchup on the buried layer implant doses. We show various DC latchup characteristics that allow us to evaluate each technology and suggest guidelines for the reduction of latchup susceptibility.

• Proceedings of the KIEE Conference
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• 1997.07d
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• pp.1292-1297
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• 1997

본 연구에서는 latch-up 개선책의 일환으로 개발중인 매립층을 갖는 retrograde well의 형성기술과 더불어 공정 단순화를 목적으로 개발된 BILLI (Buried Implanted Layer for Lateral Isolation) well 구조[1]에 대한 공정 유기 결함을 분석하고 그에 의한 소자 열화 특성을 분석 하였으며 그 개선책을 제시 하고자 하였다. 매립층 형성에 의한 유기결함은 접합 누설전류와 Gate oxide 신뢰성을 열화 시켰으나 이온주입 후 $1000^{\circ}C$ 이상의 온도에서 10sec 정도의 RTP anneal에 의해 그 소자 특성이 개선되며 표면 결함이 감소함을 알 수 있었다.

• Korean Journal of Community Nutrition
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• v.3 no.5
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• pp.685-694
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• 1998

This cross-sectional study was conducted to describe the changes of plasma cardiovascular disease(CVD) risk factors in Korea. Overnight fasting plasma levels of total cholesterol, high density lipoprotein(HDL)-cholesterol, triacylglycerol and glucose were analyzed. Blood pressure and anthropometric data were also measured. Health practice factors such as smoking status, alcohol consumption and frequency fo exercise were evaluated by a self-administered questionnaire. Questions regarding dietary habits and food preferences were also asked. Seventy eight percent of the subjects had more than one CVD risk factor. Plasma total cholesterol, triacylglycerol, and fasting blood glucose were significantly increased according to the subjects body mass index$(kg/m^2$, BMI), whereas HDL-cholesterol, low density lipoprotein(LDL)-cholesterol and blood pressure showed no significant differences with BMI. Current smokers had significantly high plasma total cholesterol, LDL-cholesterol and triacylglycerol levels. Alcohol consumption significantly increased plasma total cholesterol and fasting blood sugar, but regular exercise had no effects on the plasma CVD risk factors. Overeating and frequency of fast food consumption were positively correlated with the CVD risk score, whereas intake of grains, meats and vegetables were negatively correlated with that score. A stepwise multiple regression analysis was performed to examine the effects of specific dietary factors on plasma lipid levels. For plasma total cholesterol level, the frequency of fast food intake explained 8% of the variance, followed by habitual overeating, frequency of grain intake and high cholesterol food intake(Model $R^2$=22.4%). For plasma triacylglycerol level, preference of oily foods accounted for 7.5% of the variance, followed by eating breakfast, preference of fruit and frequency of grain intake(Model $R^2$=22.0%). The findings suggest that intervention programs to reduce the risk of CVD should focus on health practice through reducing BMI, smoking cessation and moderate or no alcohol drinking. Moreover, desirable dietary habits such as eating breakfast, not overeating and reduced intake of fast food may improve CVD risk.

• Proceedings of the Korean Society of Tribologists and Lubrication Engineers Conference
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• 1997.04a
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• pp.69-73
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• 1997

Microwave Plasma assisted CVD (Chemical Vapor Deposition) and DC Plasma CVD were used to prepare thin and thick diamond film, respectively. Diamond coated silicon nitride and fiee standing diamond thick film were eroded by silicon carbide particles. The velocity of the solid particle was about 220m/sec. Phase transformation and the other crack formation were investigated by using Raman spectroscopy and microscopy.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2006.05a
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• pp.130-132
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• 2006

In this paper, the author describes a-C films grown in pure methane plasma without any diluent gas by using RF plasma-enhanced CVD, and the variations in their structural features and surface morphologies are examined as a function of substrate temperature. Raman spectroscopy and scanning electron microscopy were performed to characterize the properties of the film.