Here is the abstract you requested from the DPC_2009_Wafer 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.
|Delivering High Reliability from a Wafer-Scale, Chip-Sized Package Incorporating a Through Silicon Via Solution|
|Keywords: TSV, Reliability, Image Sensor|
|Despite many years of endeavour through silicon vias have failed to achieve widespread commercial acceptance. There are several reasons for this notable amongst which are the high cost of the technology and the poor reliability of many proposed implementations. Points of weaknesses in a traditional through silicon via design include applying dielectric and conductive coatings to the side walls of a high aspect ratio pipe; the 90 degree bends at the top and base of the pipe that the redistribution layer must traverse and maintain connectivity during thermal cycling; and the difficulty of guaranteeing the cleanliness of the back of the bond pad so the redistribution layer can make an Ohmic contact to it, when the bond pad is the bottom of a long narrow pipe. This paper will present structural analysis and set of reliability results of a new through silicon via solution suitable for both wafer-scale chip-sized packages and stacked die wafer-scale packages. So-called ‘via-through-pad’ contacts are a novel form of interconnect that superficially resemble a through silicon via but the differences are important and have profound implications for the product cost and reliability. The process technology which is described is wholly scalable and the tool set is modeled on the printed circuit board manufacturing industry to keep the package cost low. The via-through-pad interconnects are fabricated at the wafer level to leverage the cost and throughput advantage of wafer-scale processing. Data will be presented showing via-through-pad interconnects are able to surpass by a wide margin, the exacting reliability requirements of the automotive industry, both at the package, board and assembled module levels. Examples of application based on image sensors camera modules will be presented.|
|Moshe Kriman, VP Engineering