Study on strength of soldered micro-joints of QFP devices

Tensile strength of the quad flat pack(QFP) devices were determined by STR-1000 Joint Strength Tester and compared with the joints soldered with different pitches and different solder compositions QFP and SOP(small outline package).The results indicate that for the same solder compositions,the wider the pitch is,the larger the pulling force is,i.e.the higher the tensile strength is.The tensile strength of soldered joints of QFP with pure lead is higher than that of eutectic solder and as well and as higher than that of eutectic solder itself.