Here is the abstract you requested from the IMAPS_2013 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.
|Polymer Based Interposer Providing ESD and Thermal Robustness|
|Keywords: interposer, polymer, ESD protection|
|A concept of polymer based interposer has been introduced which combines thermal stress relief and high intrinsic ESD protection capability at low cost (Shrier2013). Thermal expansion of a polymer-metal interposer system can be adjusted over a wide range to comply with thermal expansion of silicon dies or any other stacked component. The presented polymer also provides intrinsic system ESD protection beyond 8 kV IEC by a matrix of embedded metal nanoparticles. The interposer can be deployed in package-on-interposer or die-on-interposer stacks. Examples for application of polymer interposer as protection both for ICs and LEDs are presented. These examples show how interposers allow to implement very compact, ESD robust units. To realize Silicon matched CTE values for interposers, several base materials have been investigated and optimized. While previously used Kapton shows CTE values in the regime of 20 to 22 ppm/°C, polyimid derivates can deliver low single digit values of CTE. A comparison of integrated layered interposers consisting of two layers of various base material and a layer of nanoparticles embedded into a specific polymer matrix are discussed. The effectiveness of the interposer for ESD protection provided by the nanoparticle layer does not only depend on the standalone ESD robustness, but the transient voltage waveform during the pulse needs to be assessed as well. While a significant initial voltage overshoot can be detected in the first nanoseconds of a stress pulses by transmission line pulsing, it is shown that this will not harm the protected device if the fast transient is blocked e.g. by protecting inductors like bond wires or shunted by parallel diodes. Up to 15 kV IEC robustness values have been realized for integrated IC interposer solutions.|
|Karen Shrier, CEO
Electronic Polymers Newco Inc.