Technical Library | 2009-04-09 20:43:09.0
Evidence has come to light that increased solder process temperatures, specifically for lead free solder, are dramatically shortening life expectancy of components; failures do not show up during initial test, but much later on in the products life,
Technical Library | 2016-05-12 16:29:40.0
Advances in miniaturized electronic devices have led to the evolution of microvias in high density interconnect (HDI) circuit boards from single-level to stacked structures that intersect multiple HDI layers. Stacked microvias are usually filled with electroplated copper. Challenges for fabricating reliable microvias include creating strong interface between the base of the microvia and the target pad, and generating no voids in the electrodeposited copper structures. Interface delamination is the most common microvia failure due to inferior quality of electroless copper, while microvia fatigue life can be reduced by over 90% as a result of large voids, according to the authors’ finite element analysis and fatigue life prediction. This paper addresses the influence of voids on reliability of microvias, as well as the interface delamination issue.
Technical Library | 1999-05-06 13:41:18.0
Invented in 1971, the microprocessor evolved from the inventions of the transistor (1947) and the integrated circuit (1958). Essentially a computer on a chip, it is the most advanced application of the transistor. The influence of the microprocessor today is well known, but in 1971 the effect the microprocessor would have on everyday life was a vision beyond even those who created it. This paper presents the history of the microprocessor in the context of the technology and applications that drove its continued advancements.
Technical Library | 2022-09-12 14:07:47.0
Unique component handling issues can arise when an assembly factory uses highly-moisture sensitive surface mount devices (SMDs). This work describes how the distribution of moisture within the molded plastic body of a SMD is an important variable for survivability. JEDEC/IPC [1] moisture level rated packages classified as Levels 4-5a are shown to require additional handling constraints beyond the typical out-of-bag exposure time tracking. Nitrogen or desiccated cabinet containment is shown as a safe and effective means for long-term storage provided the effects of prior out-of-bag exposure conditions are taken into account. Moisture diffusion analyses coupled with experimental verification studies show that time in storage is as important a variable as floor-life exposure for highly-moisture sensitive devices. Improvements in floor-life survivability can be obtained by a handling procedure that includes cyclic storage in low humidity containment. SMDs that have exceeded their floor-life limits are analyzed for proper baking schedules. Optimized baking schedules can be adopted depending on a knowledge of the exposure conditions and the moisture sensitivity level of the device.
Technical Library | 2018-06-18 13:43:56.0
Thermal influences can significantly compromise the service life, capacity and especially the operational safety of HV batteries. In order to prevent damage due to excessive temperatures, large quantities of heat-conducting potting media are used here. Scheugenpflug has developed a new system solution for fast and reliable application of these materials.
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 | 2003-04-18 12:05:57.0
The popular tin (Sn) rich lead free solders are causing severe corrosion to many of the materials used in today's Wave Solder systems. Users are experiencing higher maintenance frequency and reduced life of wave solder machine components. This paper describes the effects of Sn rich solders in contact with various materials and discusses alternate methods to alleviate this problem.
Technical Library | 2009-10-22 02:38:13.0
An electronic product's reliability has the potential to make or break its manufacturer and can be life-threatening in many safety critical applications. Conformal coatings have long been used to protect electronic assemblies from their operating environment but can vary hugely in their protective performance. It is the objective of this article to explain in detail why it is important to qualify coating products to the relevant standards and how different coating types affect performance.
Technical Library | 2016-09-15 17:10:40.0
This paper describes the purpose, methodology, and results to date of thermal endurance testing performed at the company. The intent of this thermal aging testing is to establish long term reliability data for printed wiring board (PWB) materials for use in applications that require 20+ years (100,000+ hours) of operational life under different thermal conditions. Underwriters Laboratory (UL) testing only addresses unclad laminate (resin and glass) and not a fabricated PWB that undergoes many processing steps, includes copper and plated through holes, and has a complex mechanical structure. UL testing is based on a 5000 hour expected operation life of the electronic product. Therefore, there is a need to determine the dielectric breakdown / degradation of the composite printed circuit board material and mechanical structure over time and temperature for mission critical applications.
Technical Library | 2022-03-02 21:52:34.0
In today's consumer-driven electronic marketplace many products have a limited useful life and component suppliers are moving to shorter product lifecycles. However, there are several industries that require semiconductor components to have a much longer lifecycle. In many cases application lifecycles within the Industrial, Automotive, Medical, Aerospace and Defense sectors may extend up to 30 years or more. As a result, an ongoing component supply becomes critical to sustaining these applications throughout their useful lifecycle. For this reason, it is often a requirement that semiconductor components be stored for extended periods of time after production ends.
