Ways to solve wetability soldering issues with solder paste solutions
In the microelectronics assembly and repair industries, wetability can be a major issue. As the size of components decrease, parts become more and more susceptible to the surface tension of solder paste. 01005-sized components are the most problematic pieces to work with, but this affects parts that are 0201, 0402 and 0603 as well. Kimco Distributing carries a full line of Kester solder paste, which helps solve the problem of wetability, but changing the solder paste is not the only solution.
In an ideal world, parts and pad sizes always match up perfectly. Anyone who has repaired laptops or other electronics, though, knows this is not always true. Wettability can be an issue with any microelectronic work, but it especially comes into play when the component and pad size are not perfect matches. This scenario often results in excess solder paste on the pads, which in turn leads to uneven thermal mass distribution. Ultimately, this causes tombstoning.
Selecting a different solder paste from Kimco Distributors can overcome wettability issues. In addition to changing solder paste, using a different type of wire is another way to alter the wettability. Often this is a less practical solution, since components have their own wires. The wire solder, however, can be altered. Kimco Distirbutors has a Kester wire solder for virtually every type of wire. Finally, since reflow also contributes to tombstoning, using a different flux is another possible solution. Changing to a Kester flux does not directly solve the wettability issue, but it may be enough to prevent tombstoning, which is often the real issue at hand.