Technical Library | 2023-01-17 17:58:36.0
Heterogeneous integration has become an important performance enabler as high-performance computing (HPC) demands continue to rise. The focus to enable heterogeneous integration scaling is to push interconnect density limit with increased bandwidth and improved power efficiency. Many different advanced packaging architectures have been deployed to increase I/O wire / area density for higher data bandwidth requirements, and to enable more effective die disaggregation. Embedded Multi-die Interconnect Bridge (EMIB) technology is an advanced, cost-effective approach to in-package high density interconnect of heterogeneous chips, providing high density I/O, and controlled electrical interconnect paths between multiple dice in a package. In emerging architectures, it is required to scale down the EMIB die bump pitch in order to further increase the die-to-die (D2D) communication bandwidth. Aa a result, bump pitch scaling poses significant challenges in the plated solder bump reflow process, e.g., bump height / coplanarity control, solder wicking control, and bump void control. It's crucial to ensure a high-quality solder bump reflow process to meet the final product reliability requirements. In this paper, a combined formic acid based fluxless and vacuum assisted reflow process is developed for fine pitch plated solder bumping application. A high-volume production (HVM) ready tool has been developed for this process.
Technical Library | 2022-01-12 19:26:19.0
Autonomous vehicles have the potential to revolutionize the automotive industry and are gaining immense attention from academia as well as industry. However, facets of autonomous vehicle systems related to the interconnection of independent components pose vulnerabilities to the system as a whole. These vulnerabilities aren't guaranteed to be solved by traditional security methods. Blockchain technology is a powerful tool that can aid in improving trust and reliability in such systems.
Technical Library | 2023-11-20 17:42:33.0
Zero-defect strategies and increased demands on the production of assemblies are making quality assurance in electronics production increasingly important. Continous miniaturization of components, ever higher packing densities and the associated hard-to-view assembly areas, as well as the increased use of components such as BGAs, QFNs and QFPs, pose a considerable challenge when it comes to high-precision quality control.
Technical Library | 2021-06-15 15:11:43.0
Today's automated dispensing for electronics manufacturing is a complex and precise process in order to meet the challenges posed by ever more demanding assembly and component technology requirements. Dedicated dispenser technology is key to success in meeting challenging applications in a production environment with precision and repeatability. The major components that comprise a dispenser will be described, with a view toward understanding the importance of each; the result will illustrate how these sub-systems combine to create high-volume dispensing platforms. Real world examples with data substantiating the speed and accuracy obtained for some of the most common advanced dispensing applications in the market will be demonstrated such as high speed surface mount adhesive, wafer level Underfill and shield edge interconnects.
Technical Library | 2022-01-05 23:10:11.0
Waste electrical and electronic equipment or e-waste generation has been skyrocketing over the last decades. This poses waste management and value recovery challenges, especially in developing countries. Printed circuit boards (PCBs) are mainly employed in value recovery operations. Despite the high energy costs of generating crushed and milled particles of the order of several microns, those are employed in conventional hydrometallurgical techniques. Coarse PCB pieces (of order a few centimetres) based value recovery operations are not reported at the industrial scale as the complexities of the internal structure of PCBs limit efficient metal and non-metal separation.
Technical Library | 2013-01-03 20:27:54.0
Electronics assemblies with large flip-chip BGA packages can be prone to either pad cratering or brittle intermetallic (IMC) failures under excessive PCB bending. Pad cratering cracks are not detected by electrical testing or non-destructive inspection methods, yet they pose a long term reliability risk since the cracks may propagate under subsequent loads to cause electrical failure. Since the initiation of pad cratering does not result in an instantaneous electrical signature, detecting the onset of this failure has been challenging. An acoustic emission methodology was recently developed by the authors to detect the onset of pad cratering. The instantaneous release of elastic energy associated with the initiation of an internal crack, i.e., Acoustic Emission (AE), can be monitored to accurately determine the onset of both pad cratering and brittle intermetallic (IMC) failures.
Technical Library | 2014-08-28 17:09:23.0
The fastest growing package types in the electronics industry today are Bottom Termination Components (BTCs). While the advantages of BTCs are well documented, they pose significant reliability challenges to users. One of the most common drivers for reliability failures is the inappropriate adoption of new technologies. This is especially true for new component packaging like BTCs. Obtaining relevant information can be difficult since information is often segmented and the focus is on design opportunities not on reliability risks (...)Commonly used conformal coating and potting processes have resulted in shortened fatigue life under thermal cycling conditions. Why do conformal coating and potting reduce fatigue life? This paper details work undertaken to understand the mechanisms underlying this reduction. Verification and determination of mechanical properties of some common materials are performed and highlighted. Recommendations for material selection and housing design are also given.
Technical Library | 2016-02-04 19:11:47.0
In a typical mechatronic manufacturing functional test setup, actual load simulations are usually done by connecting the DUT outputs to power or ground in order to establish either a high or low side driver. Each output is connected with different load and the test will either be sequential or concurrent. At lower power levels, these can usually be managed with general purpose switches. However, when it comes to higher power levels of currents more than 5 amps, such switching and loading might pose a greater challenge. Furthermore, critically in the manufacturing line, the tradeoff between cost and test time would have a great influence on the test strategy.This paper will present some key points to design a cost effective high power switching and load management solution.
Technical Library | 2024-06-23 22:03:59.0
The melting temperatures of most lead-free solder alloys are somewhat higher than that of eutectic Sn/Pb solder, and many of the alloys tend to wet typical contact pads less readily. This tends to narrow down the fluxing and mass reflow process windows for assembly onto typical organic substrates and may enhance requirements on placement accuracy. Flip chip assembly here poses some unique challenges. The small dimensions provide for particular sensitivities to wetting and solder joint collapse, and underfilling does not reduce the demands on the intermetallic bond strength. Rather, the need to underfill lead to additional concerns in terms of underfill process control and reliability. Relatively little can here be learned from work on regular SMT components, BGAs or CSPs.
Technical Library | 2020-11-24 23:01:04.0
The miniaturization trend is driving industry to adopting low standoff components or components in cavity. The cost reduction pressure is pushing telecommunication industry to combine assembly of components and electromagnetic shield in one single reflow process. As a result, the flux outgassing/drying is getting very difficult for devices due to poor venting channel. This resulted in insufficiently dried/burnt-off flux residue. For a properly formulated flux, the remaining flux activity posed no issue in a dried flux residue for no-clean process. However, when venting channel is blocked, not only solvents remain, but also activators could not be burnt off. The presence of solvents allows mobility of active ingredients and the associated corrosion, thus poses a major threat to the reliability. In this work, a new halogen-free no-clean SnAgCu solder paste, 33-76-1, has been developed. This solder paste exhibited SIR value above the IPC spec 100 MΩ without any dendrite formation, even with a wet flux residue on the comb pattern. The wet flux residue was caused by covering the comb pattern with 10 mm × 10 mm glass slide during reflow and SIR testing in order to mimic the poorly vented low standoff components. The paste 33-76-1 also showed very good SMT assembly performance, including voiding of QFN and HIP resistance. The wetting ability of paste 33-76-1 was very good under nitrogen. For air reflow, 33-76-1 still matched paste C which is widely accepted by industry for air reflow process. The above good performance on both non-corrosivity with wet flux residue and robust SMT process can only be accomplished through a breakthrough in flux technology.
