• Macromolecular Research
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• 제14권3호
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• pp.300-305
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• 2006

The chemical structure of a semi-aromatic polyimide-I, which was prepared by the chemical imidization of cyclopentanetetracarboxylic dianhydride and 2,2-bis(4-aminophenyl)hexafluoropropane, was characterized by $^{13}C-NMR$ spectroscopy. The chemically imidized polyimide-I was used for the preparation of a photosensitive polyimide (PSPI) through the addition of benzophenone and benzophenone oxime hexamethylene diurethane (BOHD), a photobase generator containing oxime-urethane groups. The polyimide-I film containing benzophenone and BOHD was not soluble in 2.38 wt% tetrabutylammonium hydroxide solution in $H_2O$. However, it became soluble following irradiation with 310 nm UV light. A positive tone image with a resolution of $5{\mu}m$ was obtained with this PSPI, having sensitivity($D_c$) of $1.2J/cm^2$ and contrast(${\gamma}_p$) of 1.08. Thus, a polyimide, which is not intrinsically photosensitive, can become photosensitive through the addition of a photobase generator containing oxime-urethane groups as a photosensitive compound.

• 폴리머
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• 제30권4호
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• pp.362-366
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• 2006

Pentacene을 폴리이미드(PI) 배향막 위에 증착하면 기판 위에 수직으로 배열하는 것을 편광 FTIR 실험을 이용하여 확인하였다. Pentacene 이 PI 필름 위에 수직으로 증착할 때, 러빙하지 않은 즉, 등방성인 PI 필름 위에서는 특정한 방향성이 없이 배열하는 반면 러빙한 PI 필름 위에서는 러빙 방향과 평행하게 pentacene의 ring 평면이 배열하였다. Pentacene 특성 피크 중 ring 평면에 평행한 transition dipole moment 를 가지는 $1296cm^{-1}$ 밴드는 러빙 방향과 평행일 때 그리고 ring 평면에 수직한 진동운동의 $908cm^{-1}$ 밴드는 러빙 방향에 수직인 편광 IR 스펙트럼 에서 피크가 크게 나타나는 것이 관찰되었다. 이와 같은 평광 FTIR 실험 결과는 기판에 수직으로 증착하는 pentacene 분자들이 PI 필름의 러빙 방향과 평행하게 ring 평면이 배열을 할 때 나타날 수 있는 것으로, PI 사슬들의 배향이 pentacene 분자들의 배향에 영향을 미치는 것을 보여주는 것이다.

• 한국전기전자재료학회논문지
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• 제16권2호
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• pp.138-143
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• 2003

A double spiral thin-film inductor with a NiFe magnetic core is integrated with DC-DC converter IC. The NiFe core is deposited on a polyimide film as the thinckness of NiFe is 2.5~3.5 ${\mu}$m. Then, copper conductor line is deposited on the NiFe core with double spiral structure. Process integration is performed by sequential processes of etching the polyimide film deposited both top and bottom of the NiFe core and electroplation copper conductor line from exposed metal pad of the DC-DC converter IC. Process integration is simplified by elimination planarization process for top core because the proposed thin-film inductor has a bottom NiFe core only. Inductor of the fabricated monolithic DC-DC converter IC is 0.53 ${\mu}$H when the area of converter IC and thin-film inductor are 5X5$\textrm{mm}^2$ and 3.5X2.5$\textrm{mm}^2$, respectively. The efficiency is 72% when input voltage and output voltage are 3.5 V and 6 V, respectively at the operation frequency of 8 MHz.

• 마이크로전자및패키징학회지
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• 제29권2호
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• pp.59-64
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• 2022

연성인쇄회로기판에 사용되는 스크린 프린팅(screen-printing, SP) Ag/폴리이미드(polyimide, PI) 구조의 필 테스트 시 필링 속도 및 박막 적층 구조가 필 강도에 미치는 영향을 분석하기 위해, PI/SP-Ag, PI/SP-Ag/전해도금 Cu, 전해도금 Cu/SP-Ag/PI의 3가지 적층 구조에 대해 필링 속도에 따른 90° 필 테스트를 수행하였다. PI 박막을 필링하는 2가지 구조에서는 필링 속도에 상관없이 필 강도가 거의 일정하게 유지된 반면, Cu/Ag 금속 박막 필링 구조에서는 필링 속도가 증가할수록 필 강도가 크게 증가하는 경향을 보였다. 이는 필링 속도에 따른 90° 굽힘 소재의 소성변형에너지 차이에 기인한 것으로 판단된다. 인장속도에 따른 인장 시험 결과, 변형 속도 증가에 따른 Cu/Ag 금속 박막의 유동응력 및 인성 증가가 Cu/Ag/PI 구조에서의 필링 속도에 따른 금속 박막의 90° 굽힘 소성변형에너지 및 필 강도 증가의 주 원인으로 판단된다. 반면, 점탄성 소재인 PI의 경우 변형 속도에 따른 기계적물성 차이가 금속에 비해 상대적으로 작아서, PI/Ag 및 PI/Ag/Cu 구조에서는 필링 속도에 따른 PI의 90° 굽힘 소성변형에너지 및 필 강도 변화가 상대적으로 적은 것으로 판단된다.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1997년도 추계학술대회 논문집 학회본부
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• pp.296-298
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• 1997

The performance of thin film pressure sensors with polyimide and silicon oxide as a insulating layer between the stainless steel diaphragm and the Cu-Ni strain gauges is presented. The polyimide was spun on the stainless steel diaphragm and cured in an oven. The silicon oxide was deposited by rf sputtering. The thin film pressure sensor with silicon oxide as a insulating layer showed a better nonlinearity and a lower hysteresis.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1997년도 하계학술대회 논문집 C
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• pp.1531-1533
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• 1997

We prepared polyimide film by electrophoretic deposition onto glass film as a sensing materials of humidity, and treated with plasma discharging as a function of discharging power to improve performance of the sensor. Then evaluated the characteristics of polyimide on humidity.

• 한국표면공학회지
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• 제27권5호
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• pp.273-284
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• 1994

Thermal behavior of Cu-Cr thin alloy films has been investigated by SEM, AES, and TEM. Cu-Cr alloy films containing 3wt% Cr, 8wt% Cr have been sputter-deposited onto polyimide substrates and heat treated at $400^{\circ}C$ for 2hrs in the various atmosphere. Before heat treatment, Cu and Cr content in the film are uniform through the thickness and oxygen content in the film is negligible. Redistribution of Cr, Cu, and O in the film due to heat treatment depends on the Cr content and heat treatment atmoshpere. There kinds of thermal behavior are ascribed to the formation of surface and interface oxides as well as internal oxidation. Hillocks are observed on the surface of Cu-Cr alloy films which have been heat treated in N2. The hillocks are composed of large grainss of Cu.

• 한국재료학회지
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• 제18권9호
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• pp.486-491
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• 2008

The effect of annealing treatment conditions on the interfacial adhesion energy between electrolessplated Ni film and polyimide substrate was evaluated using a $180^{\circ}$ peel test. Measured peel strength values are $26.9{\pm}0.8,\;22.4{\pm}0.8,\;21.9{\pm}1.5,\;23.1{\pm}1.3,\;16.1{\pm}2.0\;and\;14.3{\pm}1.3g/mm$ for annealing treatment times during 0, 1, 3, 5, 10, and 20 hours, respectively, at $200^{\circ}C$ in ambient environment. XPS and AES analysis results on peeled surfaces clearly reveal that the peeling occurs cohesively inside polyimide. This implies a degradation of polyimide structure due to oxygen diffusion through interface between Ni and polyimide, which is also closely related to the decrease in the interfacial adhesion energy due to thermal treatment in ambient conditions.

• 한국전기전자재료학회논문지
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• 제16권12호
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• pp.1110-1114
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• 2003

We have investigated the generation of pretilt angle for a nematic liquid crystal (NLC) alignment with rubbing alignment method on polyimide surfaces using thin plastic substrates. It was found that monodomain alignment of NLC is obtained with rubbing alignment method on polyimide surfaces using thin plastic substrates. The NLC pretilt angles generated are about 3$^{\circ}$ by the rubbing alignment method on thin plastic substrates, However, the pretilt angle are at about 1.7$^{\circ}$ lower on the glass substrate than on thin plastic substrate. We obtain that AFM (atomic force microscope) image of rubbed PI surface with polymer film has formed the micro-groove structure at the low curring temperature (120$^{\circ}C$). However, no grooves are obtained on the glass substrate at the same temperature. It is considered that this alignment may be attributed to roughness of micro-groove substrate. The tilt angle increases with increasing baking temperature for making polyimide layer using glass substrate. It was concluded that the pretilt angle in the polyimide surface is attributable to the increasing of imidization rato.

• 한국전기전자재료학회논문지
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• 제18권2호
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• pp.148-152
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• 2005

Atmospheric low-temperature plasma was produced using dielectric barrier discharge (DBD) plate-type plasma reactor and high frequency of 13.56 Hz. The surfaces of polyimide films for insulating and packaging materials were treated by the atmospheric low-temperature plasma. The contact angle of 67$^{\circ}$ was observed before the plasma treatment. The contact angle was decreased with deceasing the velocity of plasma treatment. In case of oxygen content of 0.2 %, electrode gap of 2 mm, the velocity of plasma treatment of 20 mm/sec, and input power of 400 W, the minimum contact angle of 13$^{\circ}$ was observed. The chemical characteristics of polyimide film after the plama treatment were investigated using X-ray photoelectron spectroscopy (XPS), and new carboxyl group bond was observed. The surfaces of polyimide films were changed into hydrophilic by the atmospheric low-temperature plasma. The polyimide films having hydrophilic surface will be very useful as a packaging and insulating materials in electronic devices.