• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2007년도 7th International Meeting on Information Display 제7권1호
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• pp.348-351
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• 2007

A pure polyimide substrate and polyimide substrate with nano-silica additive have been formed on glass by coating. The a-Si:H TFT arrays have been formed on such polyimide substrate for driving TNLCD.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2003년도 춘계학술대회 논문집 디스플레이 광소자분야
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• pp.81-83
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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 LNC is obtained with rubbing alignment method on polyimide surfaces using thin plastic substrates. The generated NLC pretilt angles are about $3^{\circ}$ by the rubbing alignment method on thin plastic substrates, However, the pretilt angle measured at about $1.7^{\circ}$ lower on the glass substrate than by thin plastic substrate. 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 pretilt angle in the polyimide surface is attributable to the increasing of imide rato.

• 한국신재생에너지학회:학술대회논문집
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• 한국신재생에너지학회 2009년도 춘계학술대회 논문집
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• pp.153-155
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• 2009

In this study, we fabricated the $Cu(In,Ga)Se_2$ (CIGS) thin-film solar cells by using a polyimide substrate. The CIGS thin-film was deposited on Mo coated polyimide substrate by a 3-stage co-evaporation technique. Because the polyimide shows thermal transformation at about $400^{\circ}C$, the substrate temperature of co-evaporation process was set to below $400^{\circ}C$. Corresponding solar cell showed a conversion efficiency of 7.08 % with $V_{OC}$ of 0.58 V, $J_{SC}$ of 24.99 $mA/cm^2$ and FF of 0.49.

• 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.

• 한국기계가공학회지
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• 제12권2호
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• pp.62-67
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• 2013

The influence of internal stress and joint strength(shear, tensile) according to the deposition conditions was investigated by the Polyimide substrate and ZnO thin film. Deposition thickness and temperature affect the internal stress and the internal stress was minimum at the 60nm and $200^{\circ}C$ of the deposition conditions. Tensile strength is large at the deposition condition that shear strength is large and the shear strength was about 50% of the tensile strength. The shear strength and tensile strength were large at deposition condition that internal stress was small. Crack occurred near the joint interface of Polyimide substrate and progressed along the interface until the final fracture.

• 마이크로전자및패키징학회지
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• 제12권3호
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• pp.207-212
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• 2005

Al, Ti, Ta 및 Cr 박막을 DC 마그네트론 스퍼터링방법으로 0 - 800 W의 RF 바이어스로 폴리이미드 기판에 가하면서 증착한 후 금속박막의 접착성을 연구하였다. 접착력은 $90^{\circ}$ 필 테스트로 평가하였다. 필 테스트 결과 모든 시편에서 기판에 RF 바이어스를 가하면 접착력이 향상되었다. RF바이어스를 가한 시편은 필링 도중 계면근처의 폴리이미드 내에서 파괴가 일어나면서 소성변형이 심하게 발생하였다. 단면 투과전자현미경 관찰에 의하면 금속/폴리이미드 계면은 분명하지 않고 복잡한 형상을 띄고 있었다. 이런 복잡한 계면은 RF 바이어스의 영향으로 생겼으며 접착력 향상의 주요 요인이었다.

• Macromolecular Research
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• 제17권8호
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• pp.568-574
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• 2009

We investigated the sintering and consolidation phenomena of silver nanoparticles under various thermal treatment conditions when they were patterned by a contact printing technique on polyimide substrate films. The sintering of metastable silver nanoparticles commenced at 180 $^{\circ}C$, where the point necks were formed at the contact points of the nanoparticles to reduce the overall surface area and the overall surface energy. As the temperature was increased up to 250 $^{\circ}C$, silver atoms diffused from the grain boundaries at the intersections and continued to deposit on the interior surface of the pores, thereby filling up the remaining space. When the consolidation temperature exceeded 270 $^{\circ}C$, the capillary force between the spherical silver particles and polyimide flat surface induced the permanent deformation of the polyimide films, leaving crater-shaped indentation marks. The bonding force between the patterned silver metal and polyimide substrate was greatly increased by the heat treatment temperature and the mechanical interlocking by the metal particle indentation.

• Elastomers and Composites
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• 제59권3호
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• pp.91-96
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• 2024

A novel aromatic polyimide containing the 4-tert-butyl group was prepared from 4-tert-butyl-1,2-phenylene bis(4-aminobenzoate) and 4,4'-(hexafluoroisopropylidene)diphthalic anhydride (6FDA). 4-tert-Butyl-1,2-phenylene bis(4-aminobenzoate) was synthesized from 4-tert-butyl catechol and 4-nitrobenzoyl chloride. The poly(amic acid) was transformed into a polyimide via chemical imidization. The polyimide was soluble in N-methyl-2-pyrrolidone (NMP) and could be cast into a flexible and transparent film. The thermal stability of the polyimide was decreased slightly due to the pendant tertbutyl group.

• Applied Microscopy
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• 제25권1호
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• pp.130-138
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• 1995

TEM specimen preparation methods have been examined to characterize Cu oxide particles in the polyimide film. Polyimide films were prepared by coating polyamic acid onto Cu films which had been deposited on TEM-mask and glass substrates and Cu foil, followed by thermal curing. In case of TEM-mask, direct observation was possible without further preparation. In other cases, TEM specimen were made by separating polyimide film from the substrate. Polyimide films were removed from glass and Cu foil by dissolving glass in HF solution and Cu foil in $H_{2}SO_{4}$ solution. TEM-mask observation confirms that fine $Cu_{2}O$ particles precipitate in the polyimide as a result of reaction of polyamic acid with Cu. However $Cu_{2}O$ particle reacts with HF and $H_{2}SO_{4}$ solution during dissolving the substrate and interpretation could be misled. It is concluded characterization of $Cu_{2}O$ particle in polyimide using TEM-mask is better than other methods.

• 한국전기전자재료학회논문지
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• 제23권5호
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• pp.374-378
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• 2010

The effects of $O_2$ plasma pretreatment on the properties of Ga-doped ZnO films on polyimide substrate were studied. GZO films were fabricated by RF magnetron sputtering process. To improve surface energy and adhesion between the polyimide substrate and the GZO film, $O_2$ plasma pretreatment process was used prior to GZO sputtering. As the RF power and the treatment time increased, the crystallinity increased and the contact angle decreased significantly. When the RF power was 100 W and the treatment time was 120 sec, the resistivity of GZO films on the polyimide substrate was $1.90{\times}10^{-3}{\Omega}-cm$.