• 한국컴퓨터정보학회논문지
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• 제27권11호
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• pp.115-121
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• 2022

표면실장기술(SMT)에서 솔더 크림을 바르는 장비인 스크린 프린터는 패드가 작아지면서 도포 불량이 많이 발생한다. 이를 해결하기 위해 최근에는 젯 프린터를 사용하고 있다. 그런데 젯 프린터 헤드에 적용하는 밸브의 끝단 노즐을 깨끗하게 청소하지 않으면 과납이나 오도포가 발생한다. 이를 방지하기 위해서는 노즐을 주기적으로 청소해줘야 한다. 본 논문에서는 젯 프린터의 안정적인 솔더 크림 도포를 위하여 기존 기술보다 더욱 안정적으로 청소하는 방법을 제시하였다. 이 방법은 35mm 폭의 무진천을 재단하여 롤 형태로 감아 놓고, 반대쪽에 DC 기어드 모터로 회전시켜 닦는다. 그 결과 약 2,000회 도팅 주기로 청소를 했을 때 노즐 표면에 솔더 페이스트가 남지 않고 잘 닦이는 것을 확인하였다.

• 대한기계학회논문집A
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• 제31권1호
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• pp.11-17
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• 2007

In this paper, we present a design, analysis, fabrication and performance test of the novel DoD metal-jet system for application to the high-density and high-temperature-melting materials. The theoretical analysis of the metal-jet nozzle system is derived by using electro-mechanical analogy. Based on the theoretical analysis results, we design the metal-jet print head system and fabricate the metal-jet system, which can eject the droplet of lead-free metal solder in high-temperature. In the experimental test, we set up the test apparatus for visualization of the droplet ejection and measure the ejected droplet volume and velocity. As a result, the diameter, volume and the velocity of the ejected droplet are about 65 $\mu$m $\sim$ 70 $\mu$m, 145p1 $\sim$ 180 pl and 4m/s, which shows quite good agreement with the theoretical analysis results of the 75 $\mu$m-diameter and 220 pl-volume of droplet. In comparison with the experimental result, the errors of diameter and volume are 7% $\sim$ 13% and 18 $\sim$ 34%, respectively.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2008년도 제39회 하계학술대회
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• pp.1450-1451
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• 2008

To investigate the reliability of the conductive lines patterned by ink-jet printing, we evaluated the reliability of the ink-jet printed silver (Ag) patterns according to the guide lines built up as assessments methods in the production of conventional rigid printed circuit boards. The assessment methods include the uniformity of line width and space, adhesive strength, dielectric withstand, solder float, thermal shock test and pressure cooker test (PCT). To prepare assesment vehicles, different regular test patterns were created by Ag ink-jet printing on the same polyimide substrate for each of assessment methods.

• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2004년도 Asia Display / IMID 04
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• pp.188-190
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• 2004

As an effort to reduce cost and lead-time and to increase flexibility and responsiveness, manufacturers are using digital printing in numerous process steps. Typically, these processes require the precise dispensing of various fluids. Piezo ink jet printheads are proving to be reliable tools for depositing active materials such as light emitting polymers (LEP) for mobile phone displays and color filter inks for liquid crystal displays. Ink jets are also being used to provide uniform coatings of polyimide alignment layers and spacers for LCDs. Success with legend printing on PCBs using ink jets has encouraged the design of equipment for directly printing both etch resist and solder mask for PCBs. Development of printers for passive components such as capacitors and resistors is underway. This paper will present the attributes of an ink jet printhead designed to a precision deposition tool and discuss how it is being used to digitally print electronic and flat panel display components. Status of commercialization of digital printing will be discussed along with issues to be resolved before wide adoption takes place.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2006년도 춘계학술대회 논문집
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• pp.585-586
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• 2006

In this paper, we present a design, analysis, fabrication and performance test of the novel DoD metal-jet system for application to the high-density and high-temperature-melting materials. Based on the theoretical analysis, we design the metal-jet print head system and fabricate the metal-jet system, which can eject the droplet of lead-free metal solder in the high-temperature. In the experimental test, we set up the test apparatus for visualization of the droplet ejection and measure the Ejected droplet volume and velocity. As a result, the diameter, volume and the velocity of the ejected droplet are about $65-70{\mu}m$, 145-180 pl and 4m/sec. We also fabricate vertical and inclined 3D micro column structures using the present molten metal inkjet system. The measured geometries of the micro column structures are about height of $2,100{\mu}m$, diameter of $200{\mu}m$ and aspect ratio of 10.5 for vertical micro column and $1,400{\mu}m$ of height and $150{\mu}m$ of diameter for $65^{\circ}$-inclined micro column, respectively.