• Electronic Materials Letters
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• 제14권6호
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• pp.749-754
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• 2018

Previous studies have reported on the mechanical robustness and chemical stability of flexible amorphous indium gallium zinc oxide (a-IGZO) thin-film transistors (TFTs) on plastic substrates both in flat and curved states. In this study, we investigate how the polyimide (PI) substrate affects hydrogen concentration in the a-IGZO layer, which subsequently influences the device performance and stability under bias-temperature-stress. Hydrogen increases the carrier concentration in the active layer, but it also electrically deactivates intrinsic defects depending on its concentration. The influence of hydrogen varies between the TFTs fabricated on a glass substrate to those on a PI substrate. Hydrogen concentration is 5% lower in devices on a PI substrate after annealing, which increases the hysteresis characteristics from 0.22 to 0.55 V and also the threshold voltage shift under positive bias temperature stress by 2 ${\times}$ compared to the devices on a glass substrate. Hence, the analysis and control of hydrogen flux is crucial to maintaining good device performance and stability of a-IGZO TFTs.

• Transactions on Electrical and Electronic Materials
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• 제13권1호
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• pp.23-26
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• 2012

A zero-shrinkage sintering process in which the shrinkage of x-y axis is controlled to be zero is in great demand due to the trend of high integration in the ceramic modules. Among the zero-shrinkage sintering processes that are available, the proposed glass infiltration method where the viscous but fluidic glass infiltrates of the $Al_2O_3$ particles in the structure of $Al_2O_3$/glass/$Al_2O_3$ during firing is one of the applicable methods. However, the above proposed glass infiltration method has the problem of the warpage-like delamination. This occurred at the outermost surface of the multiple-bundle substrate. It is thought that the decomposed gas rapidly expands in low viscous glass to create vacant space. To solve this problem, the vacant space was tamped with $Al_2O_3$ particles to lead to the actual improvement of the sintered properties. With 15 wt% of tamping $Al_2O_3$ particles in glass, most of the vacant space disappeared. Fully densified zero-shrinkage substrate without delamination can be obtained.

• 대한용접접합학회:학술대회논문집
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• 대한용접접합학회 2000년도 특별강연 및 추계학술발표대회 개요집
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• pp.284-286
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• 2000

• 한국레이저가공학회지
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• 제13권1호
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• pp.6-10
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• 2010

Crystallization of 100 nm thick amorphous silicon (a-Si) films on glass substrates was carried out by using a double laser irradiation method. Depending on a-Si deposition method or glass types, the quality of crystallized silicon film varies significantly. For a-Si films deposited with high concentration of impurities, large grains or high crystallinity can not be achieved. Crystallization with different a-Si deposition methods confirmed that for the polycrystallization of a-Si films on glass substrates, controlling the impurity density during substrate preparation is critical.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2008년도 하계학술대회 논문집 Vol.9
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• pp.66-66
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• 2008

Most of the properties of ITO films depend on their substrate nature, deposition techniques and ITO film composition. For the display panel application, it is normally deposited on the glass substrate which has high strain point (>575 degree) and must be deposited at a temperature higher than $250^{\circ}C$ and then annealed at a temperature higher than $300^{\circ}C$ in order to high optical transmittance in the visible region, low reactivity and chemical duration. But the high strain point glass (HSPG) used as FPDs is blocking popularization of large sizes FPDs because it is more expensive than a soda lime glass (SLG). If the SLG could be used as substrate for FPDs, then diffusion of Na ion from the substrate occurs into the ITO films during annealing or heat treatment on manufacturing process and it affects the properties. Therefore proper care should be followed to minimize Na ion diffusion. In this study, we investigate the electrical, optical and structural properties of ITO films deposited on the SLG and the Asahi glass(PD200) substrate by rf magnetron sputtering using a ceramic target ($In_2O_3:SnO_2$, 90:10wt.%). These films were annealed in $N_2$ and air atmosphere at $400^{\circ}C$ for 20min, 1hr, and 2hrs. ITO films deposited on the SLG show a high electrical resistivity and structural defect as compared with those deposited on the PD200 due to the Na ion from the SLG on diffuse to the ITO film by annealing. However these properties can be improved by introducing a barrier layer of $SiO_2$ or $Al_2O_3$ between ITO film and the SLG substrate. The characteristics of films were examined by the 4-point probe, FE-SEM, UV-VIS spectrometer, and X-ray diffraction. SIMS analysis confirmed that barrier layer inhibited Na ion diffusion from the SLG.

• 한국세라믹학회지
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• 제37권5호
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• pp.425-431
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• 2000

Cobalt ferrite thin films on Corming glass substrate were fabricated by a sol-gel method. Cobalt ferrite thin films with the grain size of 20-35 nm and thickness of 50nm were obtained. Rapid thermal annealing (RTA) and Annealing processes were adopted for comparison of characteristics of the films. Coercivity values were changed with thermal condition and magnetization values were increased as a function of soaking time. With prolonged soaking time, however, it was decreased because of the diffusion of cations from the glass substrate. The RTA process in preparation of cobalt ferrite thin film was the effective way to prevent and to form a single spinel phase in reduced soaking time. The film heated at 600$^{\circ}C$ for 30 minutes by RTA had coercivity of 2,600 Oe, saturation magnetization 460 emu/㎤, and Mr$.$$\delta$ of 1.43 memu/$\textrm{cm}^2$.

• 한국마이크로전자및패키징학회:학술대회논문집
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• 한국마이크로전자및패키징학회 1999년도 추계 기술심포지움 논문집
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• pp.111-115
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• 1999

The $Li_2O-MgO-MgF_2-SiO_2$glasses with addition of $B_2O_3$ were investigated in order to make glass-ceramics for low temperature firing substrate. Glasses were made by melting at $1450^{\circ}C$ in the electronic furnace and crystallized at $750^{\circ}C$. After the crystallization, crystal phases and microstructure were observed. The crystal phases were polycrystalline of lithium boron fluorphlogopite and lithium fluorhectorite. The crystal shape was changed to grande type from needle type with the increase in $B_2O_3$ contents. Average particle size of the glass-ceramics aftar water swelling was $3.77{\mu}{\textrm}{m}$. The optimum sintering temperature and sintering shrinkage of the substrate were $900^{\circ}C$ and 13.4vol%, respectively.

• 마이크로전자및패키징학회지
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• 제9권3호
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• pp.25-29
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• 2002

단일이온교환 공정을 도입하여 평판디스플레이에 사용되는 기판유리를 대상으로 이온교환 거동 및 기계적 특성에 대하여 조사하였다. 효과분석으로는 온도와 시간 변화에 따른 $K^+$ 이온의 침투깊이, 이온교환량, 밀도, 열팽창계수를 관찰하였다. 기판유리의 기계적 특성으로는 3점 곡강도와 만곡변화를 관찰하였으며, 광학현미경을 사용하여 곡강도 측정 후 파괴된 시편의 형태를 조사하였다.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2004년도 제6회 학술대회 논문집 일렉트렛트 및 응용기술연구회
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• pp.18-22
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• 2004

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. Also, EO characteristics of the TN-LCD with a rubbed PI surface based on polymer are almost the same as that of the TN-LCD with a rubbed PI surface based on glass. However, the transmittances of the TN-LCD with a rubbed PI surface based on polymer is less than that with a rubbed PI surface based on glass.

• 한국진공학회지
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• 제9권4호
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• pp.367-372
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• 2000

$SiO_2$/Si 기판과 비정질 slide glass 기판 위에 대향타겟식스퍼터법(FTS법)을 이용하여 sputtering current 0.1~0.8 A, 방전 가스압 0.5~3mTorr, 기판온도 R.T~$400^{\circ}C$에서 ZnO 박막을 증착하였다. sputtering current 0.4 A, 가스압력 0.5 mTorr, 기판온도 30$0^{\circ}C$에서 증착된 ZnO/glass 박막과 ZnO/$SiO_2$/Si 박막의 $\Delta\theta_{50}$은 $3.8^{\circ}$와 $2.98^{\circ}$를 각각 나타내었다. 이러한 조건에서 FTS법은 비정질 slide glass 기판 위에서도 우수한 c-축 배향성을 갖는 ZnO 박막을 제작할 수 있다는 것을 알 수 있었다.