Here is the abstract you requested from the DPC_2009_FlipChip technical program page. This is the original abstract submitted by the author. Any changes to the technical content of the final manuscript published by IMAPS or the presentation that is given during the event is done by the author, not IMAPS.
|Impact of Underfill Fillet Design on Package Reliability|
|Keywords: Underfill, Reliability, Fillet|
|Selecting which underfill material to use in the manufacturing of flip chip ball grid array packages is critical for ensuring proper reliability performance. In addition to choosing the optimal material properties for an underfill, it is also important to select the best method of dispense. It is common to vary dispense properties such as temperature, weight, and pattern. This presentation will focus on underfill fillet design, and how the fillet size can affect package reliability. Underfill dispense variables will be discussed in detail and how they influence the final fillet shape. Modeling data and empirical reliability data will be presented to explain exactly what type of impact fillet design can have on package reliability. Specifically, for the underfill material used in this evaluation, the key dispense parameters to influence fillet design is dispense temperature and weight. The critical failure mode observed during reliability stressing due to excessive fillet size is bulk silicon edge cracks.|
|Brett Wilkerson, Flip Chip Package Integration Engineer