The Knowledge Base: The Era of Advanced Packaging
Standard of Excellence: Finding and Developing Future Leaders in Manufacturing
Global Sourcing Spotlight: Navigating the Variables of Holiday Schedules in Global Sourcing
Enhancing Board Level Reliability for Harsh Environments of Large WLP’s Reworkable Edgebond and Edgefill Adhesives at SMTAI 2019
August 19, 2019 | ZymetEstimated reading time: 1 minute
At the SMTA International 2019 technical conference, Portland State University and Zymet will present their investigations on enhancing the board level reliability of large WLP’s, for harsh environment applications. WLP’s, which include WLCSP’s and FO-WLP’s, offer a path to lower weight, smaller formfactor, and higher performance.
Figure 1. 12-mm WLCSP’s without adhesive (a), dot-edgebonded with reworkable edgebond adhesive (b), full-edgebonded with reworkable edgebond adhesive (c), and edgefilled with reworkable edgefill adhesive (d).
However, their low coefficient of thermal expansions is not well matched to that of commonly used organic substrates. This mis-match result in early solder joint fatigue and early failures in thermal cycle tests, tests that are more and more difficult to pass as the package gets larger and the conditions become more severe. This limitation constricts the user to using either smaller package sizes or to limiting the use of such packages to less severe environments. The investigation shows that reworkable adhesives can enhance the board level reliability of large WLP’s, even for harsh environment applications.
Thermal cycle testing from -40°C to +125°C was performed on a 12-mm WLCSP that was assembled with SAC solder on a rigid PCB. Non-bonded assemblies (Figure 1a) are compared with those bonded with a reworkable edgebond adhesive, applied in both dot-edgebond and full-edgebond configurations (Figure 1b & 1c), and with a reworkable edgefill adhesive (Figures 1d). The expected poor performance of the non-bonded package is confirmed. All three bonded configurations significantly improved performance, raising characteristic life by 300% to 1000%, depending on the configuration.
The paper, “Multi-axis Loading Effect on Edgebond and Edgefilled WLCSP Thermal Cycling Performance”, will be presented at Session APT4: Wafer Level Packaging, on Wednesday, September 25th, 2019. For more information about reworkable edgebond adhesives and edgefill adhesives, visit Zymet at Booth #941, SMTAi 2019, Rosemont Convention Center, Rosemont, IL, September 22 - 26, 2019. Or, email the company at info@zymet.com. Zymet is a global supplier of adhesives and encapsulants, focused on the development and manufacture of enabling materials for the electronics industry.
Share on:
Suggested Items
Book Excerpt: The Printed Circuit Assembler’s Guide to... Low-Temperature Soldering, Vol. 2, Chapter 5
12/23/2024 | I-Connect007 Editorial TeamChapter 5 introduces the advantages of using low-temperature soldering for through-hole components, including cost efficiency, reliability improvement, and reduced warpage. Also covered: the evaluation of different fluxes and the performance of HRL3 in wave soldering and selective soldering processes.
Overview of Soldering Systems With Vacuum
12/18/2024 | Dr. Paul Wild, Rehm Thermal Systems GmbHWhen soldering electronic assemblies, the focus of the vacuum application is on the removal of volatile substances from the solder joints and the associated reduction of pore formation. Particularly in the thermal management of power electronics components, pores can cause so-called hotspots with higher temperatures due to their poor heat conduction. These hotspots can lead to overheating of the components on the one hand and to thermally induced destruction of the solder structure on the other.
I-Connect007 Editor’s Choice: Five Must-Reads for the Week
12/13/2024 | Andy Shaughnessy, I-Connect007This week, Peter Tranitz discusses the upcoming Pan-European Electronics Design Conference, set for Jan. 29-30 in Vienna, Austria. Pete Starkey brings us a review of the most recent EIPC Technical Snapshot webinar, which featured a global PCB maker update by Dr. Hayao Nakahara. Don't miss our interview with Manfred Huschka, who explains how companies can begin their own China Plus One plan. Stan Farnsworth breaks down photonic soldering and discusses its use in soldering materials that are not typically compatible. I also enjoyed Dan Beaulieu’s discussion on the value of consistency, and why just showing up for work is half the battle, especially in an inconsistent, evolving industry like ours.
Advancing Photonic Soldering
12/11/2024 | Nolan Johnson, SMT007 MagazineStan Farnsworth, director of customer satisfaction at PulseForge, discusses the advancements in photonic soldering that highlight its energy efficiency and versatility. Over the past two years, the company has refined its applications for flexible substrates and energy reduction, finding that photonic soldering allows the processing of materials that typically aren’t thermally compatible and offers significant energy savings compared to traditional methods.
Indium Introduces New ROL0 and Halogen-free Flux-cored Wire
12/11/2024 | Indium CorporationIndium Corporation announced the global availability of CW-807RS, a new high-reliability, halide- and halogen-free flux-cored wire that improves wetting speeds and cycle times for electronics assembly and robot soldering applications.