Here is the abstract you requested from the polymers_2016 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.
|Ultra-thick photo resist for FO-WLP|
|Keywords: Photo resist, Plating, Fan out|
|The mobile device market is continuing to see tremendous growth as we move toward the Internet of Things (IoT) era. In response, the requirements for the semiconductor packaging industry are getting ever more challenging. Among others, FO-WLP (Fan-Out Wafer Level Packaging) has been widely proposed as one of a highly viable solutions in the 3D packaging area. In the last decades, JSR has developed multiple negative tone resists (ELPAC THB series) for re-distribution layers (RDL), solder bumps, copper pillars, and micro bumps, These resists show good lithographic properties, good chemical resistance for various plating chemicals and good strippability. Based on our depth of knowledge in these technologies, we have recently placed strong focus on developing new resists for high copper pillars (> 100um) to support, to efficiently fabricate the innovative packages being designed by FO-WLP players. Here, we show the results of our latest ultra-thick photo resist. It shows fast photo speed, straight profiles, fine resolution with an aspect ratio of four and beyond. On top of that, the new material shows excellent coating performance to achieve 100um thickness by single coating and over 200um thickness by double coating on 12 inch wafers. Good coating uniformity and TTV (Total Thickness Variation) without bubbles, defects, wrinkles or other errors, is also demonstrated. The resulting high quality copper pillars fabricated after plating with the new THB resist will be proven as well. Details of this unique concept, and material performance, are described in this presentation. We strongly believe that our new ultra-thick photo resist will be the best candidate for FO-WLP.|
JSR Micro N.V.