Technical Library | 2009-12-23 16:55:08.0
Leading up to the development of lead-free soldering alloys, Horizontal Convection* was developed for the reflow process. Getting the correct temperature profile, with the narrow process window in lead-free applications, is now more important than ever. In each chamber or zone, air is circulated toward one side of the oven above the PCB and toward the opposite side of the oven below the PCB, forming a cyclone around the board. The forced air circulation results in a uniform temperature profile along the entire circuit board assembly. This technology is ideal for the precise profiles needed for lead free soldering.
Technical Library | 2015-08-20 15:51:08.0
Temperature and Humidity on Selective Conformal Coating It is well known that selective conformal coating on printed circuit board (PCB) assemblies provides unparallel protection for PCB’s. Nevertheless, concentrated conditions of humidity, water, and high temperatures can have negative effects on the conformal coating itself causing it to fail and become inapt for its intended purpose. Taking this into consideration, it is prudent to choose the right type of conformal coating that best suits the application and environmental conditions under which an assembly is likely to undergo in use. The proper conformal coating will significantly reduce the likelihood of failure/rejection, saving both valuable time and money for any manufacturing process.
Technical Library | 2018-09-10 08:44:08.0
Issue: Moisture and bubbles in your dispensing material with larger quantities Solution: Scheugenpflug’s 55-gal Barrel Agitator Station Barrel agitators for casting resins take their technology from the paint sector. They fall short of meeting the special demands of the auto, medical, aeronautics and electronics industries. They can’t guarantee a solid seal on the barrels – often containing expensive, moisture sensitive resins – allowing the humidity of the surrounding environment to damage the material. Also, conventional barrel agitators, as opposed to smaller units, cannot work in a vacuum to process materials directly.
Technical Library | 2021-03-18 20:07:08.0
X-ray tomography is a promising technique that can provide micron level, internal structure, and three dimensional (3D) information of an integrated circuit (IC) component without the need for serial sectioning or decapsulation. This is especially useful for counterfeit IC detection as demonstrated by recent work. Although the components remain physically intact during tomography, the effect of radiation on the electrical functionality is not yet fully investigated. In this paper we analyze the impact of X-ray tomography on the reliability of ICs with different fabrication technologies.
Technical Library | 2021-04-01 14:40:08.0
We demonstrate the viability of using ultra-thin sheets of microbially grown nanocellulose to build functional medical sensors. Microbially grown nanocellulose is an interesting alternative to plastics, as it is hydrophilic, biocompatible, porous, and hydrogen bonding, thereby allowing the potential development of new application routes. Exploiting
Technical Library | 2008-04-15 14:43:08.0
The increasing demands for miniaturization and better functionality of electronic components and devices have a significant effect on the requirements facing the printed circuit board (PCB) industry. PCB manufactures are driving for producing high density interconnect (HDI) boards at significantly reduced cost and reduced implementation time. The interconnection complexity of the PCB is still growing and today calls for 50/50 μm or 25/25 μm technology are real. Existing technologies are unable to offer acceptable solution. Recently the Laser Direct Imaging (LDI) technology is considered as an answer for these challenges.
Unipress - Institute of High Pressure Physics of the Polish Academy of Sciences
Technical Library | 2013-01-29 15:48:08.0
Choosing a new wire Cutting and Stripping (C&S) machine can be like shopping for a new car. With so many choices, where does one start? A nice, little sports car might be fun to have, but how often will it just sit there because it can’t carry a car load of kids or some odd-sized goods from the local home improvement store? You just might be better off with a midsize SUV that does a pretty good job at doing everything you need it to do.
Technical Library | 2017-03-22 20:58:08.0
Water soluble lead-free solder paste is widely used in today’s SMT processes, but the industry is slowly moving away from water soluble solder pastes in favor of no-clean solder pastes. This shift in usage of solder paste is driven by an effort to eliminate the water wash process. Some components cannot tolerate water wash and elimination of water washing streamlines the SMT process. Despite this shift, certain applications lend themselves to the use of water soluble solder paste.This paper details the research and development of a new water soluble lead-free solder paste which improves on the performance characteristics of existing technologies.
Technical Library | 2017-06-01 17:12:08.0
The corrosion of Nickel-Palladium-Gold (Ni-Pd-Au) finish terminals in humid environments is known to be reduced with the application of a conformal coating such as acrylic. Corrosion has a higher rate of occurrence around the terminal ‘knee’ of a surface mount component, which may be reduced with the application of conformal coatings. Although radio frequency (RF) plasma processing is generally known to enhance conformity of conformal coating to surfaces through ionic bombardment, the effect on the functionality of assembled printed circuit boards (PCB) is not as well known. The purpose of this study is to assess whether RF plasma processing can enhance the adhesive and coverage qualities of an acrylic conformal coating on PCBs, specifically on Ni-Pd-Au terminals with a knee, and if plasma processing has an effect on the electrical functionality of components and fully assembled PCB.
Technical Library | 2019-02-06 22:02:08.0
The High Density Packaging (HDP) user group has completed a project to evaluate the majority of viable Dk (Dielectric Constant)/Df (Dissipation Factor) and delay/loss electrical test methods, with a focus on the methods used for speeds above 2 GHz. A comparison of test methods from 1 to 2 GHz through to higher test frequencies was desired, testing a variety of laminate materials (standard volume production with UL approval, low loss, and "halogen-free" laminate materials). Variations in the test board material resin content/construction and copper foil surface roughness/type were minimized. Problems with Dk/Df and loss test methods and discrepancies in results are identified, as well as possible correlations or relationships among these higher speed test methods.
