Here is the abstract you requested from the IMAPS_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.
|Temporary Wafer Bonding Materials with Mechanical/Laser Debonding Technologies for Semiconductor Device Processing|
|Keywords: temporary wafer bonding, mechanical debond, laser debond|
|Wafer-level packaging (WLP) has been adopted at a large scale, predominately driven by mobile markets targeting high flexibility, performance, and small form-factor size. Various WLP technologies have undergone tremendous innovation and evolution, such as package-on-package (PoP), fan-out integration, and through-silicon-via (TSV). As a technology enabler, temporary wafer bonding and debonding technologies have been widely studied and developed in recent years in order to handle thinned substrates (<100 µm), which are not self-supporting in post-processing applications. In addition, for some applications, temporary bonding materials must be able to withstand temperatures of up to 250ºC in high-vacuum conditions; some applications in power devices even require the temporary bonding materials to survive temperatures at or above 350ºC. Therefore, a simple and efficient bonding/debonding process with ease-of-material handling and survivability in high temperature conditions is in high demand, particularly with regard to reduction of cost-of-ownership and throughput improvement. In this study, a series of formulations based on polar thermoplastics were developed for temporary wafer bonding applications in 3D-IC, which target high temperature survivability and improved adhesion to prevent the premature delamination during downstream wafer processing. All of the materials outlined in this study provide high thermal stability of up to 250ºC or higher, and are bonded utilizing fully treated carrier wafers, which can be selectively debonded by either mechanical peel or laser after high-temperature heat treatment. Any bonding material residue that may remain on the device wafer after debonding can be easily cleaned using common industrial solvents. Wafers bonded with these materials demonstrate lower overall stack total thickness variation (TTV) after grinding and have successfully survived 200°C plasma-enhanced chemical vapor deposition (PECVD) processing. The results demonstrated good adhesion without any premature delamination during grinding and PECVD processing.|
|Xiao Liu, Scientist
Brewer Science Inc.