Issue link: https://iconnect007.uberflip.com/i/550232
44 SMT Magazine • August 2015 the BGA. On the other hand the JEDEC speci- fication allows up to 0.23 mm (9 mil) warpage for large BGAs and 0.17 mm (6.7 mil) warpage for small BGAs. The authors submit that these warpage specifications are too generous and will allow substantial opportunity for conditions of poor contact between ball and paste during reflow; resulting in HoP defects. Case Studies Six different case studies collected from par- ticipating companies will be discussed in this paper. Each of these cases is a real life prod- uct example of HoP defects found either in production or as a result of field returns. This paper will review the corresponding warpage analysis of the BGAs and compare these to the specification. figure 7: Warpage table from JeiTa eD-7306 [5] . Figure 8: Warpage table from JEDEC Publication 95, SPP-024 issue A [6] . WARPAGE ACCEPTANCE PROPOSAL continues FeAture