MICROSTRUCTURE AND INTERFACIAL INTERMETALLIC OF Sn-3.0Ag-0.5Cu/Sn-58Bi SOLDER JOINT FOR PACKAGE-ON-PACKAGE TECHNOLOGY

Abstract

In this study, the effect of growth microstructure on diffusion and intermetallic compound of Sn-58Bi/SAC305 solder joint with different of SAC305 size and reflow temperature had been studied. For effect of different size, it used 180°C reflow temperature and 5minute reflow time with the size of SAC305 solder ball was 800μm, 900μm and 1000μm. For the reflow temperature would reflow at 160°C,170°C, 180°C, and 190°C for 5minute reflow time. After the reflow process, a sample would go through a several processes such as molding, grinding and polishing before undergoing material characterization. The diffusion area had shown an inversely relationship with SAC305 size and linearly relationship with temperature and time reflow. Besides, the IMC thickness was thinner with increasing of SAC305 size. In this finding, the area of Sn-58Bi/SAC305 solder joint could be predicted to enhance the package on package technology.