Hi, customer did dip & look solderability testing due to observations on oxidation between lead and IC package.
Here is illustration of the oxidation picture, parts with fairly new DC 2122. This does not seem to the roughened lead frame: https://e2e.ti.com/support/logic-group/logic/f/logic-forum/718449/faq-why-do-the-leadframes-look-strongly-oxidized-or-corroded and please correct me if I am wrong.
Here is the picture for after dip & look. The red circled areas showed poor solder paste coverage; which was also the areas identified for solderability.
The concerns are how seriously this lack of solder coverage in the areas between leads and IC package; will affect the performance on the boards.
Is it necessary to strip the tin coating of the leads and re-tin the lead surfaces in order to remove the oxidation and fully cover the leads?
Please kindly advise.