Technical Library | 2021-01-13 21:34:29.0
Package-on-Package (PoP) is a popular technology for fabricating chipsets of accelerated processing units. However, the coefficient of thermal expansion mismatch between Si chips and polymer substrates induces thermal warpage during the reflow process. As such, the reflow temperature and reliability of solder joints are critical aspects of PoP. Although Sne58Bi is a good candidate for low-temperature processes, its brittleness causes other reliability issues. In this study, an in-situ observation was performed on composite solders (CSs) made of ...
Technical Library | 2019-06-06 00:19:02.0
More and more people and things are using electronic devices to communicate. Subsequently, many electronic products, in particular mobile base stations and core network nodes, need to handle enormous amounts of data per second. One important link in this communication chain is high speed pressfit connectors that are often used to connect mother boards and back planes in core network nodes. These new high speed pressfit connectors have several hundreds of thin, short and weak pins that are prone to damage. Small variations in via hole dimensions or hole plating thickness affect the connections; if the holes are too small, the pins may be bentor permanently deformed and if the holes are too large they will not form gas tight connections.The goal of this project was to understand how rework of these new high speed pressfit connectors affects connection strengths, hole wall deformations and plating cracks.
Technical Library | 2011-08-04 19:29:53.0
This work covers two major projects aimed at increasing quality and efficiency on a high mix, low volume surface mount electronics production line. Specifically the installation of a ten zone reflow oven and an enhanced changeover method for SMT pick and
Technical Library | 2013-09-05 17:44:14.0
Surface plasmon polaritons (SPPs) are localized surface electromagnetic waves that propagate along the interface between a metal and a dielectric. Owing to their inherent subwavelength confinement, SPPs have a strong potential to become building blocks of a type of photonic circuitry built up on 2D metal surfaces; however, SPPs are difficult to control on curved surfaces conformably and flexibly to produce advanced functional devices. Here we propose the concept of conformal surface plasmons (CSPs), surface plasmon waves that can propagate on ultrathin and flexible films to long distances in a wide broadband range from microwave to mid-infrared frequencies.