• Transactions on Electrical and Electronic Materials
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• v.9 no.4
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• pp.156-162
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• 2008

We report results on a study of inductively coupled plasma (ICP) etching of Parylene-C (poly-monochloro-para-xylylene) films using an $O_2$ gas. Effects of process parameters on etch rates were investigated and are discussed in this article from the standpoint of plasma parameter measurements, performed using a Langmuir probe and modeling calculation. Process parameters of interest include ICP source power and pressure. It was shown that major etching agent of polymer films was oxygen atoms O($^3P$). At the same time it was proposed that positive ions were not effective etchant, but ions played an important role as effective channel of energy transfer from plasma towards the polymer.

• Journal of the Korean institute of surface engineering
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• v.55 no.6
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• pp.390-397
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• 2022

Parylene-C which was mainly used for industries such as electronics, machinery and semiconductors has recently been in the spotlight in the medical field due to its properties such as corrosion resistance and biocompatibility. In this study we intend to derive a plan to improve the bonding strength of Parylene-C coating with the SUS304 base material for medical use which can be applied to various medical fields such as needles, micro needles and in vitro diagnostic device sensors. Through plasma pretreatment the bonding strength between Parylene-C and metal materials was improved. It was confirmed that the coated surface was hydrophobic by measuring the contact angle and the improvement of the surface roughness of the sample manufactured through CNC machining was confirmed by measuring the surface roughness with SEM. Through the above results, it is thought that it will be effective in increasing usability and reducing pain in patients by minimizing friction when inserting medical devices and in contact with skin. In addition it can be applied to various application fields such as human implantable stents and catheters, and is expected to improve the performance and lifespan of medical parts.

• Applied Chemistry for Engineering
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• v.34 no.4
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• pp.383-387
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• 2023

The quartz crystal microbalance (QCM), commonly used in high vacuum deposition, becomes difficult to use when a thick film is deposited on the quartz, affecting the crystal's inherent vibration. In this study, a non-destructive optical measurement method was developed to measure the film's deposition rate during the in-situ film deposition process. By measuring the scattered laser intensity caused by the dimer in the parylene gas passing through the gas flow path, it was successfully confirmed that the ratio of the dimer in the parylene gas increases as the pyrolysis temperature decreases. Additionally, it was noted that the film's thickness and haze increase as the pyrolysis temperature decreases by confirming the characteristics of the visible parylene films. Through the research results, we aim to utilize the stable in-situ film deposition rate measurement system to control the precise film deposition rate of parylene films.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.19 no.1
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• pp.71-74
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• 2006

In this paper, we investigated the characterization of silicon oxide(SiOx) thin film on Ethylene Terephthalate(PET) substrates by e-beam deposition for transparent barrier application. The temperature of chamber increases from $30^{\circ}C$ to $110^{\circ}C$, the roughness increase while the Water vapor transmission rate (WVTR) decreases. Under these conditions, the WVTR for PET can be reduced from a level of $0.57 g/m^2/day$ (bare subtrate) to $0.05 g/m^2/day$ after application of a 200-nm-thick $SiO_2$ coating at 110 C. A more efficient way to improve permeation of PET was carried out by using a double side coating of a 5-${\mu}m$-thick parylene film. It was found that the WVTR can be reduced to a level of $-0.2 g/m^2/day$. The double side parylene coating on PET could contribute to the lower stress of oxide film, which greatly improves the WVTR data. These results indicates that the $SiO_2$ /Parylene/PET barrier coatings have high potential for flexible organic light-emitting diode(OLED) applications.

• Proceedings of the Korean Vacuum Society Conference
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• 2011.02a
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• pp.357-358
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• 2011

Dichloro-(2,2)-paracyclophane을 출발 물질로 하여 화학기상증착법(CVD)을 이용해 우수한 투명성과 수분 투과성을 갖는 poly(p-xylylene) 코팅 막을 얻었다. 상기 코팅 막을 얻기 위한 최적의 공정 조건은 Deposition Pressure 0.02~0.04Torr, Vaporization temperature $110{\sim}150^{\circ}C$으로 확인 되었다. 이러한 공정 조건으로 500 mm*500 mm size의 PET bare film을 코팅 기재로 사용하여 $10{\mu}m$, $20{\mu}m$의 parylene 코팅 막을 얻었고 이를 특성 분석해 보았다. 상기 코팅 막은 전체적으로 ${\pm}1{\mu}m$의 thickness uniformity가 관찰 되었고 투과율은 90% 이상을 보였으며 수분 투과율은 기재 대비 상대적으로 40%의 향상이 기대 되었다. 또한 우수한 내식성, 내염기성, 내용제성을 갖고 있었으며 PET 기재에 대해 우수한 부착력을 가지고 있었다. surface morphology는 AFM을 통해 분석하였으며 Ra가 15.123, Rq가 22.859로 측정 되었다.

• Journal of Korean Vacuum Science & Technology
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• v.3 no.1
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• pp.16-23
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• 1999

Deposition of parylene (PA) films has been explored at substrate temperatures below 2$0^{\circ}C$ and pressures below 4 torr. The film thickness was measured using AFM and the film thickness measured was 3,500-12,000$\AA$ and the growth rate was 20-70$\AA$/min. T도 dielectric constant of the deposited PA films was found to be 2.66 and the dielectric strength was in excess of 2$\times$105V/cm. The growth rate became a maximum at a precursor decomposition temperature of $600^{\circ}C$. It was found that the growth rate decreased with increasing substrate temperature, whereas it increased with increasing pressure. At a precursor decomposition temperature of 75$0^{\circ}C$ or at a deposition pressure above 1 Torr the film surface became rough due to particle formation in the gas phase. The condensation of a p-xylylene monomer on the substrate surface turned out to be a rate-limiting step in the growth of the PA films.

• Proceedings of the Korean Vacuum Society Conference
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• 2012.08a
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• pp.327-328
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• 2012

의료분야의 진단 방사선 장비는 초기의 필름방식 및 카세트에서 진보되어 현재는 디지털방식의 DR (Digital Radiography)이 널리 사용되며 이에 관한 연구개발이 활발히 진행 되고 있다. DR은 일반적으로 직접방식과 간접방식으로 나눌 수 있다. 직접방식의 원리는 X선을 흡수하면 전기적 신호를 발생 시키는 광도전체(Photoconductor)를 사용하여 광도전체 양단 전극에 전압을 인가하여 전기장을 유도한 가운데, X선을 조사하면 광도전체 내부에서 전자-전공쌍(Electron-hole pair)이 생성된다. 이것은 양단에 유도된 전기장의 영향으로 전자는 +극으로, 전공은 -극으로 이동하여 아래에 위치한 하부기판을 통하여 이미지로 변조된다. 간접방식은 X선을 흡수하면 가시광선으로 전환하는 형광체(Scintillator)를 사용하여 조사된 X선을 형광체에서 가시광선으로 전환하고, 이를 Photodiode와 같은 광변환소자로 전기적 신호로 변환하여 방사선을 검출하는 방식을 말한다. 본 연구에서는 직접방식에서 이용되는 광도전체 중 흡수효율이 높고 Mobility가 뛰어난 CdTe를 선정하여 PVD (Physical vapor deposition)방식으로 300 m의 두께를 목표로 하여 증착을 진행하였다. Chamber의 진공도가 $2.5{\times}10^{-2}$ Torr로 도달 시점부터, Substrate와 Boat에 열을 가하였다. Substrate온도는 $350^{\circ}C$, Boat온도는 $300^{\circ}C$도로 설정하여 11시간 동안 진행하였다. Substrate온도는 $303^{\circ}C$, Boat온도는 $297^{\circ}C$도부터 증착이 시작되어 선형적인 증가세 추이를 나타내어 Substrate 및 Boat온도가 설정 값에 도달 하였을 때, $25{\sim}34.4{\AA}/s$ 증착율을 나타내었다. 하부전극의 물질에 따른 CdTe증착 효율성 평가를 진행한 후, 그에 따른 전기적 특성을 알아보았다. 하부전극의 물질로는 ITO (Indium Tin Oxide), Parylene이 코팅 된 ITO, Au, Ag를 사용하였다. 하부전극의 물질 상단에 Thermal Evaporation System을 사용하여 CdTe를 증착한 후, Cdte 상단에 Au를 증착 시켜 민감도(Sensitivity)와 암전류(Dark current)를 측정하였다. 증착 결과 ITO와 Ag상단에 증착시킨 CdTe박막은 박리가 되었고, Au와 Parylene이 코팅 된 ITO에는 CdTe박막이 안정적이게 형성이 되었다. 이 두 샘플에 대하여 동일한 조건으로 민감도와 암전류를 측정 시, Parylene이 코팅된 ITO를 하부전극으로 사용한 CdTe박막은 0.1021 pA/$cm^2$의 암전류와 1.027 pC/$cm^2$의 민감도를 나타낸 반면, Au를 하부전극으로 사용한 CdTe박막은 0.0381 pA/$cm^2$의 암전류와 1.214 pC/$cm^2$의 민감도를 나타내어 Parylene이 코팅된 ITO보다 우수한 전기적 특성을 나타내었다. 따라서 Au는 CdTe박막 증착 시, 하부전극 기판으로서 뛰어난 특성을 나타내는 것을 알 수 있었다.

• The Transactions of the Korean Institute of Electrical Engineers C
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• v.49 no.12
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• pp.698-704
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• 2000

Mechanical performances of beam shaped and bridge-shaped conductive polymer actuator have been measured and analyzed varying polymerization conditions and operating conditions such as applied current, polymerizing time, frequency of the current and kinds of electrolytes. For the application of conductive polymer actuator to micropump, the diaphragm structure has been fabricated, which is composed of polypyrrole, solid polymer electrolyte and parylene. Measured results how the possibility of the practical application of conductive polymer actuator.

• Proceedings of the Korean Ceranic Society Conference
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• 2003.10a
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• pp.38.1-38
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• 2003

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2002.11a
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• pp.136-139
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• 2002

Previous valves have initial gap problem, high voltage or high pressure problem. In this paper, various micro valves with free floating structure have been fabricated and tested to solve the initial gap and high pressure problems. The paper presents how to etch Parylene-C which is a valve cap material without A1 mask layer. The maximum flow-rate of fabricated micro valve is$118{\mu\ell}$/min with $370{\mu}m$ orifice size and the leakage at the initial and reverse pressure is not observed.