Here is the abstract you requested from the IMAPS_2007 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.
|An Examination of Solder Electromigration Under Arbitrary Current Waveforms|
|Keywords: Electromigration, Solder, Current Density|
|Electromigration has been identified as a critical roadblock in the scaling of electronic device packaging. Constant power scaling has forced the various layers of device interconnects to carry current at an increased density resulting in increase in instances of electromigration. This increased current density occurs in both the thin metallization layers found in very large scale integration (VLSI) devices and at the solder interconnects found at the packaging level. Classically, electromigration research has focused on VLSI thin film interconnects. Only more recently, electromigration studies have been expanded to include conditions of solder interconnect failure. However, under both situations, research has concentrated primarily on the worst-case direct current condition, while effectively ignoring the effects of time varying current. This paper reviews and summarizes previous research of symmetrical alternating current and pulsed current electromigration in device interconnects; serving as a historical précis providing a foundation and motivation into the topic of electromigration under time varying current conditions. Specifically, alternative mean time to failure models for interconnects under both unidirectional and bidirectional pulsed currents are highlighted and will be discussed providing immediate applicable knowledge. Additionally, previously published empirical results will be summarized and discussed. Original research will also be presented. Early modeling and calculations which highlight the different operating modes of a solder interconnect and the corresponding current density profiles will be discussed. Finite element modeling will focus on primary operating frequency, interconnect size, and interconnect shape and how these parameters dictate the current density profile. Additionally empirical results will be coupled and compared with the calculated results.|
|Kevin E. Enser, Student
University at Buffalo