March 13, 2014
Optical and Acoustic Metrology Techniques for 2.5 and 3D Advanced Packaging
Presented at IMAPS Device Packaging, March 2014
The growing need for smaller, faster mobile devices that consume less power at low cost has led to advances in wafer level packaging. Traditional SoC (system on chip) solutions are moving to 2.5D interposer based SiP (system in package) solutions and Outsourced Semiconductor Assembly and Test (OSAT) houses are forming key partnerships and/or developing and offering turnkey products. The increasing complexity of the process at OSATs has generated a need for more advanced and automated measurement techniques. In this paper, we present results from the adoption of Focused Beam Ellipsometry and Picosecond Ultrasonic Sonar metrology techniques during the R&D phase of package development. The intent of this effort was to identify metrology worthy of transfer to in-line monitoring during high volume production. Measurements of various dielectric layers and multi-layer metal stacks were carried out on product wafers. The rapid, non-destructive nature of the technologies enables full wafer measurements and the small measurement spot size allows for direct measurements on product wafers on small sites (16μm).
To download the rest of the white paper