Is soldermask required for fine pitch IC soldering?

Intrigued about a discussion on the forum about whether soldermask is needed between fine pitch pads, Brian decided to test it. In the video of the test he placed solder paste on both the FR4 board material, and the soldermask, as well as some on a tined pad. Once done reflowing his results were in. Both the FR4 and the soldermask acted the […]