• Proceedings of the Korean Aquaculture Society Conference
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• 2006.05a
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• pp.173-173
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• 2006

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2007.06a
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• pp.657-658
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• 2007

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2010.11a
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• pp.95-96
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• 2010

• Proceedings of the Korean Operations and Management Science Society Conference
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• 2003.05a
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• pp.741-743
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• 2003

A surface mount machine operation policy to assemble printed circuit boards is being developed in this research. The policy includes how to assign electronic components to slots on a component rack, and how to determine placement sequences on printed circuit board. The suggested heuristic uses information about component types and closeness relationships in each component on the board to assemble. First, the size of components and closeness ratings are used to divide them into two different size groups. Then rack assignment and placement routes are developed using component type and quantity information for a small size group, and followed by a large size group. Simulation models are developed using Visual C++ for performance evaluation of the heuristic. Necessary statistical analyses are provided to show the effectiveness of the suggested heuristic.

• Journal of Korean Society for Quality Management
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• v.25 no.1
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• pp.135-141
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• 1997

The Copper-Clad Laminate (CCL) is a main electronic component of specialtype printed circuit boards (PCBs) such as Silver Through Hole PCB. This CCL should have high reliability under the aging test, and usually the test is done at a higher temperature (110-$150^{\circ}C$) than the normal. Then, this test condition of high temperature may cause such quality problems as hole eccentricity and reduction of distance between part holes. After measuring the CCL shrinkage affected by temperature, the correction factor of a press mold was a, pp.ied to solve these problems. The results showed that the tolerance of hole pitch(${\pm}$$100{\mu}m$) was satisfactory and the internal and external failure costs were reduced by 55%.

• Journal of Welding and Joining
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• v.18 no.4
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• pp.64-69
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• 2000

Reliability of PBGA(Plastic Ball Grid Array) package is very weak compared with normal plastic packages. The reliability are the lower resistance to popcorn cracking, which is reduced by moisture absorption in PCB(Printed Circuit Board). This paper adapts plasma treatment process and analyzes their effect. The contents of C and Cl decrease after plasma treatment but O, Ca and N relatively increase. The Plasma treatment to improve the adhesion between EMC(Epoxy Molding Compound) and PCB(solder mask). The degree of improvement was over 100% Max., which is depend on the properties of EMC. Ar+H$_2$as plasma gas show good result. There is a little difference in RF power and treatment time.

• The Optical Journal
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• s.139
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• pp.56-57
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• 2012

인쇄회로기판과 표면실장기술, LED, 인쇄전자, 기능성 필름, 광학 및 레이저기기 등 전자 제조산업 전반에 걸친 기술들을 총집결한 국내 최대 산업전문전시회인 'Electronics Manufacturing Korea 2012(이하 EMK2012)'가 지난 4월 11일부터 13일까지 코엑스 Hall C, D에서 펼쳐졌다. EMK2012는 SMT/PCB & NEPCON KOREA, LED Packaging EXPO, Film Technology Show와 함께 올해부터 Printed Electronics & Electronic Materials Show과 Photonics Seoul(포토닉스 서울)이 추가돼 총 5개의 전시회가 동시에 열렸다. 약 25개국 300업체가 1000부스 규모로 참가한 이번 전시회는 기존의 SMT, PCB, 전자부품, FPD 생산기자재와 더불어 LED 생산기자재, 광학기기, 레이저 산업 등 전자산업 관련 각종 생산기자재와 제품 등을 선보이며 최신 기술을 교류하는 기회였다.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.11 no.10
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• pp.773-777
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• 1998

This paper presents the results of measured permittivity of PCB sheet material in the frequency range of 0.1 ~ 2[㎓] and temperature range of 25~ 85[>$^{\circ}C$]. Microstrip lines with different physical length are implemented to measure the attenuation and phase shift of the signals through these lines. The loss factor of glass-epoxy and teflon could by calculated with the measured dielectric constant and the attenuation. From the experiment, the glass-epoxy was more influenced by temperature and frequency than teflon. The average dielectric constants of glass-epoxy and teflon within the measured frequency range are 4.48 and 2.18, respectively.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.13 no.10
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• pp.805-811
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• 2000

Reliability of PBGA(plastic ball grid array) package is weak compared with normal plastic packages. The low reliability is caused by low resistance to the popcorn cracking, which is generated by moisture absorption in PCB(prited circuit board). In this paper, plasma treatment process was used and we analyzed its effects to interface adhesion. The contents of C and Cl decrease after plasma treatment but those of O, Ca, N relatively increase. The plasma treatment improves the adhesion between EMC(epoxy molding compound) and PCB(solder mask). The grade of improvement was over 100% Max, which depends on the properties of EMC. The RMS(root mean square) roughness value of the solder mask surface increases to plasma treatment. There is little difference of adhesion in RF power and treatment time.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.23 no.1
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• pp.34-37
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• 2010

0.25 mm thickness super thin surface mounted device LED Lamp is developed with PCB type lead frame in which BT (Bismaleimide Triazine) resin is used. BT resin is removed by a laser beam in order to reduce the thermal resistance below $1\;^{\circ}C/W$ and transfer molding is used with silicone. Compared to conventional 0.4 mm thickness LED lamp, the developed LED lamp can be derived in high current and the luminance of the LED lamp is increased up to 240 mA.