Non-destructive Chemical Decapsulation Techniques for TBGA Package Devices

Abstract

Failure analysis on TBGA (Tape Ball Grid Array) package devices is a rather difficult task, due to the material used for assembly. This paper will introduce two novel techniques for non-destructive deprocessing procedures used in performing analysis on TBGA devices. These new techniques do not introduce additional failures to the devices during the deprocessing procedure. The workable TBGA devices can then be powered up and analyzed using different techniques and equipment. In the first technique, molding compound (potting resin) is removed around the tab tape area or the chip is fully exposed. The first technique will allow the analyst to inspect any bonding problems. These devices can then be analyzed using probe stations and visually inspected using microscopes. In the second technique, molding compound is partially (tab tapes and protective diode areas are not exposed) removed. These partially decapped TBGA devices, can be analyzed using testers, emission microscopes, liquid crystal, multi-curve tracer, and FIB. The advantage of this technique is to be able to analyze devices without worrying about any additional failures (such as contact, functional, and leakage failures) introduced in to the devices during deprocessing.