Effect of solder flux system on rheology and jet printing performance of solder paste

The flux system of solder paste play the most important roll in the assembly of surface mount devices in electronic industries. Rheology of solder paste is the most important parameter which affects the paste jet printing process, the solder jet printing performance affects solders joint quality and reliability directly. A clear understanding of the influence of solder flux on solder rheology and jet printing performance will be very beneficial for developing future high performance solder pastes. Compared with two mature solder paste products named ALMIT-Sn62U-SS4M and SENJU-M705-LFAC19 separately, the solder pastes studied in this paper showed a worse jet performance. It is found that homemade solder paste has a long trail and poor droplets consistency after jetting. and discusses the impacts of rehology of solder paste on solder jet printing performance.