It’s something like chip on board electronics which have that black blob of epoxy sealing them after the connections are made. This image shows those connections which use magnet wire on a DIP ...

Instead of convenient pins, BGA parts have tiny metallic balls on which solder is applied, a board is thrown through a reflow oven, and hopefully at the end, everything works. Sometimes these ...

Description: LOCTITE® 3513 is a single component, epoxy adhesive designed for use as a reworkable underfill resin for CSP (FBGA) or BGA. Product Benefits Cures rapidly on exposure to heat Low ...