Issue link: https://iconnect007.uberflip.com/i/1398328
AUGUST 2021 I SMT007 MAGAZINE 79 N/mm. A cold joint is one where the solder does not melt completely. It is oen characterized by a drastic reduction in peel strength value. Cold joints are unreliable. e solder bond will be poor and, oen, power degradation could be seen over a period of time. is defect occurs due to either soldering temperature is too low or soldering time is too short. Less heat trans- fer and inadequate capillary action leads to the cold soldering. In this case, there is no alloy- ing (joint) between silver pad and wire [20] . Dry joint is a result of inadequate flux or flux burn- out at high temperature. It mostly underlines the flux's inability to remove oxide from the pad and wire surface. Factors contributing to these defects are given in Table 2. From the table, it is clear that various factors may have adverse effects on the quality of sol- der joints. It is, therefore, important to con- sider the optimized parameters and try to min- imize external factors. Reliability Test Results ermal cycle and damp heat test were per- formed as per IEC standard 61215. IV curve data (of before and aer test) was measured using Sinton Instruments IV curve tester. e results are tabulated in Figure 9. Figure 9: Accelerated aging test results of 100 thermal cycling test and 1000 h damp heat test as per IEC61215.