Korean Institute of Surface Engineering

pISSN : 1225-8024 | eISSN : 3399-8403

공학

한국표면공학회지 (48권4호 131-135)

Characterization of the SnAg Electrodeposits according to the Current Density and Cross-sectional Microstructure Analysis in the Cu Pillar Solder Bump

전류밀도에 따른 SnAg 도금층의 특성 및 Cu 필라 솔더 범프의 단면 미세구조 측정

김상혁;홍성기;임현호;이효종;
Kim, Sang-Hyuk;Hong, Seong-Ki;Yim, Hyunho;Lee, Hyo-Jong;

동아대학교 공과대학 신소재공학과;
Department of Material Science and Engineering, Dong-A University;

DOI : 10.5695/JKISE.2015.48.4.131

Abstract

We investigated the surface morphology and the change of Ag concentration for SnAg electrodeposits according to the current density using labmade and commercial plating solutions. The concentration of Ag in the SnAg electrodeposits decreased with increasing the current density. The Ag concentrations at the conditions of over $50mA/cm^2$ were below 3 wt% and the surface was relatively smooth. Cu pillar bump was fabricated by using SnAg electroplating, and it was reflowed at $240^{circ}C$ for 90 sec. The cross-sectional microstructure was investigated by using EBSD measurement and it was found that the grain size of SnAg became smaller by increasing the number of reflow treatments.

Keywords

SnAg;Electroplating;Current density;EBSD;Microstructure;