• 한국정밀공학회지
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• 제20권8호
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• pp.76-85
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• 2003

In this paper, a technical method for removing the solder from PCBs has been proposed to simplify the pulverizing process and to get higher quality of materials for recycling of the electronic parts in the Printed Circuit Boards (PCBs). There are several techniques to remove the solder from PCB, such as physical and chemical method, vibration, suction and blowing and so on. Among them, the suction technique turned out the best method by investigation. In the suction method, there are three variables for removing the solder. They are a temperature of the thermal wire, a velocity of moving PCB and a gap between PCB and thermal wire. To find the optimal variables for the system, an experiment has been conducted by a trial and error method. The optimal variables were found $220^{\circ}C$ of temperature, 11.58mm/s of velocity, 10mm of gap (A gap between suction hole and bottom of PCBs is 5mm). The result of the experiment shows that 50% of the solder were removed.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2009년도 춘계학술대회 논문집
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• pp.327-328
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• 2009

• 한국산학기술학회논문지
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• 제13권1호
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• pp.322-328
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• 2012

본 논문은 무연 솔더를 제거하기 위한 디지털 디솔더링 시스템에 관하여 다룬다. 땜납의 모재가 유연납에서 무연납으로 변화된 작업환경에 대처하고, 설정온도에 빠르게 수렴하며 연속작업이 가능한 디솔더링 시스템을 제안한다. 제안 시스템은 디솔더링 스테이션과 디솔더링건으로 구성되며, PID 온도제어를 위한 주변회로는 8bit MCU를 중심으로 설계하였다. 제안 시스템의 성능을 확인하기 위하여 동종의 수입품과 성능을 비교한 결과, 제안시스템은 기존 시스템에 비해 작업온도 도달시간은 11초 빠르며, 리플온도의 변화량은 $1.5^{\circ}C$ 적고, 열 회복율은 약 $0.14^{\circ}C$/초 빠르게 나타남을 확인 하였다.

• 한국표면공학회지
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• 제50권3호
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• pp.155-163
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• 2017

In this study, the effects of the concentration of metal ions and the applied current density in the Sn-Ag plating solutions were examined in regards to the resulting composition and morphology of the solder bumps' surface. Furthermore the effect of any impurities present in the methanesulfonic acid used as a base acid in the Sn-Ag solder plating solution on the stability of plating solution as well as the characteristics of the Sn-Ag alloys films was also explored. As expected, the uniform bump was obtained by means of removing impurities in the plating solution. Consequently the resultant solder bump was obtained in an optimal current density of the range of $1A/dm^2$ to $15A/dm^2$, which has acceptable bump shape and surface roughness with 12inch wafer trial results.

• 한국마이크로전자및패키징학회:학술대회논문집
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• 한국마이크로전자및패키징학회 2001년도 추계 기술심포지움
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• pp.138-140
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• 2001

Fluxless flip chip bonding using plasma & ultrasonic wave was investigated in order to evaluate the effect of plasma & ultrasonic treatment on the bondability of the Sn-3.5wt%Ag solder bumped die to TSM-coated glass substrate. The $Ar+10%H_2plasma$ was effective in removing tin oxide on solder surface. The die shear strength of the plasma-treated Si-chip is higher than that of non-treated specimen but lower than that of specimen bonded with flux. The die shear strength with the bonding load at 25W ultrasonic power increased to 0.8N/bump for all bonding temperature but decreased above 1.0N/bump.