• 한국소성가공학회:학술대회논문집
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• 한국소성가공학회 2003년도 추계학술대회논문집
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• pp.101-106
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• 2003

Recent electronic equipment becomes smaller, more functional, and more complex. According to these trends, LTCC(low temperature co-fired ceramic) has been emerged as a promising technology in packaging industry. It consists of multi-layer ceramic sheet, and the circuit has 3D structure. In this technology via hole formation plays an important role because it provides an electric path for the packaging interconnection network. Therefore via hole quality is very important for ensuring performance of LTCC product. Via holes are formed on the green sheet that consists of ceramic(before sintering) layer and PET(polyethylene Terephthalate) one. In this paper we found the correlation between hole quality and process condition such as ceramic thickness, and tool size. The shear behavior of double layer sheet by micro hole punching which is different from that of single layer one was also discussed.

• 소성∙가공
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• 제13권1호
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• pp.65-71
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• 2004

Recent electronic equipment becomes smaller, more functional, and more complex. According to these trends, LTCC(low temperature co-fired ceramic) has been emerged as a promising technology in packaging industry. It consists of multi-layer ceramic sheet, and the circuit has 3D structure. In this technology via hole formation plays an important role because it provides an electric path for the packaging interconnection network. Therefore via hole qualify is very important for ensuring performance of LTCC product. Via holes are formed on the green sheet that consists of ceramic(before sintering) layer and PET(polyethylene terephthalate) one. In this paper we found the correlation between hole quality and process condition such as PET thickness and ceramic thickness. The shear behavior of double layer sheet by micro hole punching which is different from that of single layer one was also discussed.

• Asian-Australasian Journal of Animal Sciences
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• 제16권11호
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• pp.1695-1700
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• 2003

A total of 30 pork loin sections were utilized to evaluate the effects of FIR ceramic sheet in PE and vacuum package on preserving the quality of chilled pork stored at 4 and $0^{\circ}C$. Based on meat color, results indicated that pork loin packaged in ceramic sheet and control treatment showed that the samples of the control treatment tended to darken gradually in comparison with the samples at 0 day, but FIR treatment had few changes. Among the total plate counts of sliced loin in PE and loin in vacuum package under different storage times at 4 and $0^{\circ}C$, results showed that FIR ceramic sheet package treatment had lower total plate counts and significant differences (p<0.05). In VBN value, both treatments tended to rise high with the increasing of storage time, but the FIR treatment was significantly lower (p<0.05) than the control treatment. Its results had a corresponding relationship with the total plate counts. Regarding the drip loss of sliced loin in PE and loin in vacuum package, it showed that FIR ceramic sheet package treatment had lower drip loss and significant differences (p<0.01). These results showed that the use of FIR ceramic sheet package, including PE and vacuum package, is an effective method of maintaining the quality of meat.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2007년도 춘계학술대회A
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• pp.1798-1802
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• 2007

Adhesion strength of single layer ceramic capacitor sheet was measured using a peel testing system developed in this study. The peel test specimens with various dimensions were prepared from the ceramic sheet cast on the PET film. In peel test, the sheet specimen was adhered on the glass jig floating on the liquid media, which was designed to minimize the friction, and the specimen was then pulled up by micro-actuator. During the separation of the sheet from the PET film, peel force was measured. To normalize the testing condition, 3 different widths of the specimen were selected: 5, 10 and 20 mm. was used Furthermore, testing speed effect was investigated in this study. From the resullts using various testing conditions, the standard method for the peel strength testing may be suggested. Based on the testing condition, effect of peel angle on the strength was experimentally examined. It was found that the adhesive strength for the ceramic sheet is nearly identical, irrespective of the specimen width ranged from 5 to 20 mm, while the adhesive strength was increased with increasing testing speed. Furthermore, the strength was shown to be dependent on the peel angle.

• 한국전기전자재료학회논문지
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• 제18권8호
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• pp.685-689
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• 2005

In the fabrication and design of MLCCs (Multilayer Ceramic Capacitors) with Ni inner electrode for medium and high voltage, reliability and dielectric breakdown mode have been investigated. For thickness of green sheet, the relationship between the rated voltage versus the thickness of green sheet. Increasing the thickness of green sheet increases the dielectric breakdown voltage. However, a practical limit to this linear relationship occurs at 30 urn and above. As the thickness of green sheet increased, dielectric breakdown voltage and weibull coefficient is increased, but abruptly decrease at 30 urn and 36 urn. When 24 urn of green sheet thickness, weibull coefficient and dielectric breakdown voltage were 13.58 and 70 V/um respectively. The results enabling the MLCCs to demonstrate high levels of reliability at medium and high voltage.

• 한국세라믹학회지
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• 제38권9호
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• pp.860-865
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• 2001

본 논문은 출발물로서 2mol% CdO가 치환된 $0.05Pb(Mn_{1/3}Sb_{2/3})O_3-0.95Pb(Zr_{0.52}Ti_{0.48})O_3$ 분말을 제조 후, 닥터 블레이드 방법으로 green sheet를 제조하기 위한 slurry의 최적 공정첨가제 조성에 관한 연구를 수행하였다. 또한, 제조된 green sheet에 대하여 소결 특성과 두께 변환에 따른 유전 및 압전 특성을 관찰하였다. 공정첨가제의 첨가에 따른 점도거동을 통하여 slurry를 최적화하였고, TGA 분석으로 소결조건을 정하였으며, sheet의 특성에 미세구조와 XRD 등으로 측정하였다. 최적의 slurry는 고형분량 30vol%에 대해 분산제 3.0wt%에서 가장 안정화되었고, 이후 바인더/가소제(0.75/0.25) 3.0wt% 첨가시 점도는 7.55Pa${\cdot}$s이었다. Green sheet의 유전 및 압전 특성들은 각각 900$^{\circ}$C, 950$^{\circ}$C, 1000$^{\circ}$C로 소결온도를 증가함에 따라 다소 증가하였지만, 두께에 따른 특성들은 큰 변화가 관찰되지 않음을 확인하였다.

• 한국세라믹학회지
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• 제47권4호
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• pp.319-324
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• 2010

Screen printable $MoSi_2$ paste and its ceramic sheet heater were investigated. $MoSi_2$ powder without $Mo_5Si_3$ second phase, which causes so-called pest phenomena, was synthesized by SHS technique. Over glaze was also developed for preventing pest phenomenon. The maximum temperature of $MoSi_2$ ceramic heater was over $500^{\circ}C$. After several heat up and cooling cycle, the $MoSi_2$ heater reveals pest phenomenon. Conductive $MoSi_2$ paste could be used in electronic ceramics, i.e., MLCC, LTCC, HTCC, and etc.

• 소성∙가공
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• 제14권3호
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• pp.277-281
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• 2005

LTCC(Low temperature co-fired ceramic) is being recognized as a significant packaging material of electrical devices for the advantages such as relatively low temperature being needed for process, low conductor resistance and high printing resolution. In the process of LTCC electrical devices, the punched via-hole quality is one of the most important factors on the performance of the device. However, its mechanism is very complicated and optimization of the process seems difficult. In this paper, to clarify the process, via-hole punching experiments were carried out and the punched holes were examined in terms of their burr formation. The effects of thickness of PET sheet, ceramic sheet and punch-to- die clearance on via-hole quality were also discussed. Optimum process conditions are proposed and a factor $\kappa$ is introduced to express effect of the process variables.

• 한국세라믹학회:학술대회논문집
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• 한국세라믹학회 2000년도 추계총회,초청강연,특별강연,연구발표회
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• pp.68.2-68
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• 2000

• Journal of Welding and Joining
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• 제13권3호
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• pp.55-64
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• 1995

Metallizing method on ceramic surface is one of the compositing technology of ceramics and metal. The purpose of this study is to make HIC (Hybrid Intergrated Circuit) with copper metallizing method of which copper layer is formed on ceramic substrate by firing in atmosphere in lieu of conventional hybrid microcircuit systems based on noble metal. Metallizing pastes were made from various copper compounds such as Cu$_{2}$O, CuO, Cu, CuS and kaolin. And the screen printing method was used. The characteristics of metallized copper layers were analyzed through the measurement of sheet resistance, SEM, and EDZX. The results obtainted are summarized as follows; 1. The copper metallizing layers on ceramic surface can be formed by firing in air. 2. The metallized layer using Cu$_{2}$O paste showed the smallest sheet resistance among a group of copper chemical compounds. And optimum metallizing conditions are 15 minutes of firing time, 1000.deg.C of firig temperature, and 3 minutes of deoxidation time. 3. The results of EDAX analysis showed mutual diffusion of Cu and Al. 4. The kaolin plays a important role of deepening the penetration of Cu to $Al_{2}$O$_{3}$ ceramics. But if the kaolin content is too much, sheet resistance increases and copper metallizing layer becomes brittle.