Technical Library | 2013-11-21 12:01:11.0
Previous experimentation on a highly miniaturized and densely populated SMT assembly revealed the optimum stencil alloy and flux-repellent coating for its stencil printing process. Production implementation of the materials that were identified in the study resulted in approximately 5% print yield improvement across all assemblies throughout the operation, validating the results of the initial tests. A new set of studies was launched to focus on the materials themselves, with the purpose of optimizing their performance on the assembly line (...) Results of the prior tests are reviewed, and the new test vehicle, experimental setup and results are presented and discussed.
Technical Library | 2014-05-12 09:24:11.0
With the advancement of the electronic industry, Package on package (POP) has become increasingly popular IC package for electronic devices, particularly in mobile devices due to its benefits of miniaturization, design flexibility and cost efficiency. However, there are some issues that have been reported such as SIR drop due to small gap between top and bottom components, difficulty underfilling and rework due to stacked IC components and process yield issues. Some suppliers have reported using some methods such as dipping epoxy paste or epoxy flux to address these issues, but so far, no customer has reported using these methods or materials in their mass production. In order to address these issues for POP assembly, YINCAE has successfully developed a first individual solder joint encapsulant adhesive.
Technical Library | 2018-07-25 21:37:11.0
This paper will discuss the expanded use of boundary-scan testing beyond the typical manufacturing test to capture structural defects on a component/devices in a printed circuit board assembly (PCBA). The following topics will be discussed to demonstrate the capability of boundary-scan test system on how we can extend beyond typical manufacturing test: Boundary-scan as a complete manufacturing test system, Boundary-scan implementation during PCBA design stage, Implementation of boundary-scan beyond typical structural testing
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 | 2023-11-14 19:52:11.0
The continuous drive in the Electronics industry to build new and innovative products has caused competitive design companies to develop assemblies with consolidated PCB designs, decreased physical sizes, and increased performance characteristics. As a result of these new designs, manufacturers of electronics are forced to contend with many challenges. One of the most significant challenges being the processing of thru-hole components on high thermal mass PCBs having the potential to exceed 20 layers in thicknesses and have copper mass contents of over 40oz. High thermal mass PCBs, coupled with the use of mixed technologies, decreased component spacing, and the change from Tin Lead Solder to Lead Free Alloys has lead many manufacturing facilities to purchase advanced soldering equipment to process challenging assemblies with a high degree of repeatability.
Technical Library | 2023-11-20 17:30:11.0
Summary for today 1. Electronic component inspection and failure analysis. 2. Component counting and material management. 3. Reverse engineering. 4. Counterfeit detection. 5. Real-time defect verification. 6. Computed tomography (CT) techniques and how to differentiate between 2D, 2.5D, and 3D x-ray inspection. 7. Design for manufacturing (DFM) and design for x-ray inspection (DFXI). 8. Voids, bridging, and head-in-pillow failures in bottom terminated components (BTC). 9. Artificial Intelligence and x-ray inspection
Technical Library | 2016-09-01 16:21:11.0
Sn3.0Ag0.5Cu (SAC305) is currently the most popular near eutectic lead-free alloy used in the manufacturing processes. Over the last several years, the price of silver has dramatically increased driving a desire for lower silver alloy alternatives. As a result, there is a significant increase in the number of alternative low/no silver lead-free solder alloys available in the industry recently. Our previous study showed that many alternative low silver solder paste materials had good printing and wetting performance as compared to SAC305 solder pastes. However, there is lack of information on the reliability of alternative alloy solder joints assembled using alternative low silver alloy solder pastes.In this paper, we will present the reliability study of lead-free solder joints reflowed using various lead-free alloy solder pastes after thermal cycling test (3000 cycles, 0°C to 100°C). Six different lead-free pastes were investigated. SAC305 solder joints were used as the control. Low and no silver solder pastes and a low temperature SnBiAg solder pastes were also included.
Technical Library | 2017-01-05 16:55:11.0
The July 2006 implementation of ROHS exempted automotive applications from converting to lead free technology. Nine years later, all major OEM and Tier 1 automotive manufacturers have converted or are in the process of converting to lead free circuit assembly processing. Starting with SAC (SnAgCu) alloys as a baseline for lead free soldering, in the last years several specific alloys were developed in order to improve resistance to high temperature creep, vibration survival and the ability to withstand thermal cycling and thermal shock.The paper compares three different solder alloys and two flux chemistries in terms of void formation and mechanical / thermal fatigue properties. Void content and reliability data of the alloys will be presented and discussed in relation to the acceptance criteria of a Tier 1 /OEM automotive supplier. As a result, a ranking list will be presented considering the combined performance of the alloys. In order to analyze the void formation and mechanical behavior of different solder alloys and flux chemistry combinations, statistical methods are used.
Technical Library | 2019-02-13 13:45:11.0
Development of information and telecommunications network is outstanding in recent years, and it is required for the related equipment such as communication base stations, servers and routers, to process huge amount of data in no time. As an electrical signal becomes faster and faster, how to prevent signal delay by transmission loss is a big issue for Printed Circuit Boards (PCB) loaded on such equipments. There are two main factors as the cause of transmission loss; dielectric loss and conductor loss. To decrease the dielectric loss, materials having low dielectric constant and low loss tangent have been developed. On the other hand, reducing the surface roughness of the copper foil itself to be used or minimizing the surface roughness by modifying surface treatment process of the conductor patterns before lamination is considered to be effective in order to decrease the conductor loss. However, there is a possibility that reduction in the surface roughness of the conductor patterns will lead to the decrease in adhesion of conductor patterns to dielectric resin and result in the deterioration of reliability of PCB itself. In this paper, we will show the evaluation results of adhesion performance and electrical properties using certain type of dielectric material for high frequency PCB, several types of copper foil and several surface treatment processes of the conductor patterns. Moreover, we will indicate a technique from the aspect of surface treatment process in order to ensure reliability and, at the same time, to prevent signal delay at the signal frequency over 20 GHz.
Technical Library | 2023-11-20 18:49:11.0
Non-destructive testing during the manufacture of printed wiring boards (PWBs) has become ever more important for checking product quality without compromising productivity. Using x-ray inspection, not only provides a non-destructive test but also allows investigation within optically hidden areas, such as the quality of post solder reflow of area array devices (e.g. BGAs, CSPs and flip chips). As the size of components continues to diminish, today's x-ray inspection systems must provide increased magnification, as well as better quality x-ray images to provide the necessary analytical information. This has led to a number of x-ray manufacturers offering digital x-ray inspection systems, either as standard or as an option, to satisfy these needs. This paper will review the capabilities that these digital x-ray systems offer compared to their analogue counterparts. There is also a discussion of the various types of digital x-ray systems that are available and how the use of different digital detectors influences the operational capabilities that such systems provide.
