SMT(Surface Mounting Technology)용 Cu 패드의 유기솔더보전제 처리공정 및 CTQ(Critical-to-Quality)분석 = Fabrication Process and CTQ Analysis of Organic Solderability Preservatives(OSP) Finish on Cu Pad for SMT

국문 초록 (Abstract)

OSP(Organic Solderability Preservatives)표면처리는 저비용, 고신뢰성, 친환경 특성으로 기존의 금속계 표면처리인 Ni/Au 표면처리를 대체할 수 있는 공정으로 관심 받고 있다. 그러나, OSP는 저분자로 구성된 유기물이므로 여러 온도공정으로 구성된 전자패키지공정에서 제품의 변색이 필연적으로 발생하여 전체 양산수율에 미치는 영향은 매우 크다. 본 연구에서 OSP 처리된 제품을 전자패키지 공정별로 발생하는 변색수준에 따라서 시편을 분류 및 채취하여 변색원인분석 및 솔더조인트 특성평가를 수행하였으며, 기존의 표면처리공정인 Ni/Au 처리된 제품과 통계 적으로 비교 분석하였다. 따라서 변색원인에 대한 분석을 통하여 OSP 처리된 전자패키지 제품에 적용 시 발생하는 공정문제점에 대한 해결책을 제시하였다.

다국어 초록 (Multilingual Abstract)

OSP(organic solderability preservatives) finish has been considered as a very effective process for substituting the metal surface treatment of Ni/Au finish because of lower cost, interface property and environmental issue of OSP finish. However, the discoloration of OSP layer is formed during assembly process consisting of various steps of temperature. The causes of discoloration and the characterization of solder joint were investigated with a degree of discoloration and the assembly process of OSP finished products, which was also compared statistically with that of conventional Ni/Au finished products. As the results, the solution of process trouble for OSP finished products is able to be offered.

참고문헌 (Reference)

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