Ball grid assembly with solder columns

摘要

A method of making a ball grid assembly and the assembly wherein a mask (1) is provided which is not wettable by solder and through which a pattern of parallel holes (3) is provided extending to at least one of a pair of opposing surfaces. A magnet (5), preferably an electromagnet, is disposed at the other one of the opposing surfaces. Solderable magnetic pins (7) are caused to enter the holes by magnetic attraction by positioning the one surface of the mask over the pins with a portion of each of the pins extending out of the hole into which it has entered. A layer of solder (11) is formed on the portion of each of the pins extending out of a hole in the mask and this layer of solder is reflowed over the pins and over a grid of solder adherable elements (13) on the package (15) and then allowed to set. The mask is removed from the pins when the solder is again set.