Technical Library | 2023-01-17 17:50:59.0
Heller's new Condenser Tube Flux Recovery System is designed to provide more efficient flux collection than earlier Heller flux collection systems; while providing minimal down time for inspection and cleaning. The entire system easily fits within the rear of the top shell of an 1800-EXL oven. The system utilizes a different set of top shell caps specially designed to provide the best serviceability of both the flux collection system and maintenance of the heater zone blower motors.
Technical Library | 2008-05-14 15:44:58.0
This paper will review some basic past and present flux chemistries that affect flux collection methodology. It will also review some of the most common flux collection methods, self-cleaning techniques, and maintenance goals. And, finally, data will be presented from high volume production testing of an advanced flux management system.
Technical Library | 2024-09-02 17:01:54.0
A printed circuit board (PCB) is an integral component of any electronic product and is among the most challenging components to recycle. While PCB manufacturing processes undergo generations of innovation and advancement with 21st century technologies, the recycling of PCBs primarily employs 1920's shredding and separation technologies. There is a critical need for alternative PCB recycling routes to satisfy the increasing environmental demands. Previous work has developed an environmentally benign supercritical fluid process that successfully delaminated the PCB substrates and separated the PCB layers. While this work was successful in delamination of the PCB substrates, further understanding is needed to maximize the interactions between the supercritical fluid and PCB for an optimal processing scenario. As such, this research presents an exploratory study to further investigate the supercritical fluid PCB recycling process by using supercritical carbon dioxide and an additional amount of water to delaminate PCB substrates. The focus of this study is to test delamination success at low temperature and pressure supercritical conditions in comparison to the previous studies. Furthermore, material characterization methods, such as differential scanning calorimetry, dynamic mechanical analysis, and Fourier transform infrared spectroscopy, are included to study the delaminating mechanisms. Results from the recycling process testing showed that the PCB substrates delaminated easily and could be further separated into copper foils, glass fibers and polymers. Surprisingly, the material characterization suggested that there were no significant changes in glass transition temperature, crosslink density, and FTIR spectra of the PCBs before and after the supercritical fluid process.
Technical Library | 2021-08-11 01:00:37.0
Conformal coatings and potting materials continue to create issues for the electronics industry. This webinar will dig deeper into the failure modes of these materials, specifically issues with Coefficient of Thermal Expansion (CTE), delamination, cracking, de-wetting, pinholes/bubbles and orange peel issues with conformal coatings and what mitigation techniques are available. Similarly, this webinar will look at the failure modes of potting materials, (e.g Glass Transition Temperature (Tg), PCB warpage, the effects of improper curing and potential methods for correcting these situations.
Technical Library | 2024-09-02 17:31:09.0
The cracking and delamination of printed circuit boards (PCB) during exposure to elevated thermal exposure, such as reflow and rework, have always been a concern for the electronics industry. However, with the increasing spread of Pb-free assembly into industries with lower volume and higher complexity, the occurrence of these events is increasing in frequency. Several telecom and enterprise original equipment manufacturers (OEMs) have reported that the robustness of their PCBs is their number one concern during the transition from SnPb to Pb-free product. Cracking and delamination within PCBs can be cohesive or adhesive in nature and can occur within the weave, along the weave, or at the copper/epoxy interface (see Figure 1). The particular role of moisture absorption and other PCB material properties, such as out of plane expansion on this phenomenon is still being debated.
Technical Library | 2009-04-30 18:06:24.0
This presentation surveys the most significant via and via-related laminate failure mechanisms from past to present using data from current induced thermal cycling (CITC) testing, failure analysis, and other sources. The relative life and failure modes of thru vias, buried vias, and microvias (stacked vs. non-stacked) are compared, along with the affect of structure, materials, and peak temperatures on the above. The origin of via-induced laminate failures such as "eyebrow cracks" and Pb free related internal delamination is also explored.
Technical Library | 2019-05-22 21:24:05.0
voidless treatment Smaller components -> miniaturization (01005 capability) Large board handling -> dynamic preheating for large board repair Repeatable processes -> flux and paste application (Dip and Print), residual solder removal (scavenging), dispensing, multiple component handling, and traceability Operator support -> higher automation, software guidance
Technical Library | 2017-06-22 17:11:53.0
C-mode scanning acoustic microscopy (C-SAM) is a non-destructive inspection technique showing the internal features of a specimen by ultrasound. The C-SAM is the preferred method for finding “air gaps” such as delamination, cracks, voids, and porosity. This paper presents evaluations performed on various advanced packages/assemblies especially flip-chip die version of ball grid array/column grid array (BGA/CGA) using C-SAM equipment. For comparison, representative x-ray images of the assemblies were also gathered to show key defect detection features of the two non-destructive techniques.
Technical Library | 2015-05-21 18:46:31.0
In this work the reliability of an embedded planar capacitor laminate under temperature and voltage stress is investigated. The capacitor laminate consisted of an epoxy-BaTiO3 composite sandwiched between two layers of copper. The test vehicle with the embedded capacitors was subjected to a temperature of 125oC and a voltage bias of 200 V for 1000 hours. Capacitance, dissipation factor, and insulation resistance were monitored in-situ. Failed capacitors exhibited a sharp drop in insulation resistance, indicating avalanche breakdown. The decrease in the capacitance after 1000 hours was no more than 8% for any of the devices monitored. The decrease in the capacitance was attributed to delamination in the embedded capacitor laminate and an increase in the spacing between the copper layers.
Technical Library | 2016-05-30 22:54:52.0
New engineered cleaning and defluxing agents promise great improvement in cleaning and reliability for electronic assemblies. As complexity grows and dimensions shrink in high reliability electronics, the need for materials compatibility and effectiveness in cleaning and rinsing is vital.
