Noncontact electrical test of a ball grid array substrate that uses the electro-optic probing technique.

A new technique for testing a ball grid array (BGA) package substrate that uses the electro-optic (EO) probing technique is investigated. This technique can detect open circuits in the BGA substrate with a high spatial resolution. An experimental setup that uses an EO probe tip made of LiNbO3 crystal is reported along with the measurement results from a real BGA substrate.