Journal of the Microelectronics and Packaging Society (마이크로전자및패키징학회지)

The Korean Microelectronics and Packaging Society (한국마이크로전자및패키징학회)
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Reflection Characteristics of Electroplated Deposits on LED Lead frame with Plating Condition

도금인자에 따른 LED 리드프레임 상의 도금층의 반사특성

  • Kee, SeHo (Department of Materials Science and Engineering, University of Seoul) ;
  • Kim, Wonjoong (Department of Materials Science and Engineering, University of Seoul) ;
  • Jung, JaePil (Department of Materials Science and Engineering, University of Seoul)
  • 기세호 (서울시립대학교 신소재공학과) ;
  • 김원중 (서울시립대학교 신소재공학과) ;
  • 정재필 (서울시립대학교 신소재공학과)
  • Received : 2013.06.03
  • Accepted : 2013.06.27
  • Published : 2013.06.30
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Abstract

The surface roughness and reflectivity of electroless-plated Sn-3.5 wt%Ag on a LED (light emitting diode) lead frame were investigated. Cu electroplating was carried out prior to electroless plating of Sn-3.5Ag to improve the reflectivity of the Sn-3.5Ag deposit. In order to investigate the effect of stirring speed and temperature of the plating solution, surface roughness and reflectivity was measured. The experimental results revealed that the thickness of the deposit layer increased with stirring speed and temperature of the plating solution. Stirring speed is increased from 100 to 300 rpm, the surface roughness was reduced from 0.513 to 0.266 ${\mu}m$, and the reflectivity increased from 1.67 to 1.84 GAM. As temperature of the plating solution increased from 25 to $45^{\circ}C$, the surface roughness reduced from 0.507 to 0.350 ${\mu}m$, and the reflectivity increased from 1.68 to 1.84 GAM.

본 연구에서는 LED 리드프레임 상에 Sn-3.5wt%Ag를 무전해도금하여 표면 거칠기와 반사율을 측정하였다. Sn-3.5wt%Ag를 도금하기에 앞서 Sn-3.5wt%Ag 도금층의 반사율을 향상시키기 위하여 Cu 전해도금을 실시하였다. 도금 후 도금액의 교반속도와 온도가 도금층의 표면 거칠기와 반사율에 어떠한 영향을 미치는지 알아보기 위하여 각각의 도금인자에 대해서 표면 거칠기와 반사율을 측정하고자 하였다. 교반속도가 100~300 rpm으로 증가함에 따라 표면 거칠기는 0.513 ${\mu}m$에서 0.266 ${\mu}m$으로 감소하였으며, 반사율은 1.67 GAM에서 1.86 GAM으로 증가하였다. 또한 온도가 $25{\sim}45^{\circ}C$로 증가함에 따라 표면 거칠기는 0.507 ${\mu}m$에서 0.350 ${\mu}m$으로 감소하였으며, 반사율은 1.68 GAM에서 1.84 GAM으로 증가하였다.

Keywords

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