Technical Library | 2010-06-10 21:01:48.0
This paper researches the effectiveness of the R.O.S.E. cleanliness testing process for dissolving and measuring ionic contaminants from boards soldered with no-clean and lead-free flux technologies.
Technical Library | 2011-03-10 18:59:02.0
History shows that the electronics assembly industry is always up for a good challenge. This was proven with the successful move from through-hole to SMT assembly, the elimination of CFCs from the cleaning process and implementation of lead
Technical Library | 2009-03-19 20:23:54.0
Over the past several years, post-reflow defluxing of circuit assemblies has gained in popularity. Microminiaturization of components and boards, combined with higher expected reliability and increased product liability, have contributed to the prominence of defluxing. Lead-free solder paste - with its higher reflow temperatures and negative effects on flux - increase the likelihood of post-reflow defluxing to increase a product's reliability and aesthetic appearance.
Technical Library | 1999-05-07 11:24:21.0
Many manufacturers have now completed the conversion to no clean solder paste. Many factors governed this initial conversion, among those being cosmetics, solder ability, and process ability. In circuit testing or probing through no clean solder paste residues has topically not been a major factor in the conversion decision for several reasons. Due to board design, solder paste was only used on one side of the board and not subjected to testing...
Technical Library | 2007-07-19 15:15:11.0
ROSA is a surface restoration technique that removes hard to reduce species like metal oxides or sulfides. At the time of its development, the focus was on solderability and compliance to environmental regulations. Industry trends and regulatory changes as a result of the Montreal Protocol were the driver for much of the concern over environmental compliance. The result was an increase in the development of no-clean and water soluble fluxes and the removal of halogenated cleaning chemistries.
Technical Library | 2019-06-03 21:07:34.0
The objective of this White Paper is to provide users of the above products in the electronics industry a clear understanding of the different types of stencil cleaning paper/fabrics that are currently available. Fine pitch applications are more the norm now and so the performance of stencil cleaning rolls is more critical than ever before. This White Paper will give solder paste stencil printing engineers and purchasing professionals an insight into the main products on the market, thereby enabling them to make informed decisions.
Technical Library | 2023-05-22 16:49:42.0
Our customers' issues • Apertures are getting smaller • Paste does not release as well • Contaminates the bottom of the stencil • Increases defects / reduces yield Insufficient solder Bridging Solder balls on surface of PCB Flux residue • Requires more frequent cleaning • Reduced efficiency (wasted time) • Increased use of consumables (cost) USC fabric (use "cheap" fabric to reduce cost) Lint creates more defects Cleaning chemistries (use IPA to reduce cost) IPA breaks down flux and can create more defects
Technical Library | 2019-05-24 07:26:39.0
Soldering system vendor SEHO runs a Technology Center in its headquarters in Germany, in which all available machines are exhibited and demonstrated. Additionally, the SEHO Academy provides knowledge as a perfect balance of theory and practical application. In both facilities soldering fume occurs, which has damaging effects on human health, manufacturing equipment and products. That's why the company had installed several air cleaning solutions in terms of fume extraction technology. How and why they take care of clean air is the subject of this article.
Technical Library | 2017-07-27 16:51:57.0
Reliability Expectations of Highly Dense Electronic Assemblies is commonly validated using Ion Chromatography and Surface Insulation Resistance. Surface Insulation Resistance tests resistance drops on both cleaned and non-cleaned circuit assemblies. It is well documented in the literature that SIR detects ionic residue and the potential of this residue to cause leakage currents in the presence of humidity and bias. Residues under leadless components are hard to inspect for and to ensure flux residue is totally removed. The question many assemblers consider is the risk of residues that may still be present under the body of components.
Technical Library | 2020-11-04 17:57:41.0
Residues present on circuit boards can cause leakage currents if not controlled and monitored. How "Clean is Clean" is neither easy nor cheap to determine. Most OEMs use analytical methods to assess the risk of harmful residues. The levels that can be associated with clean or dirty are typically determined based on the exposed environment where the part will be deployed. What is acceptably clean for one segment of the industry may be unacceptable for more demanding segments. As circuit assemblies increase in density, understanding cleanliness data becomes more challenging. The risk of premature failure or improper function is typically site specific. The problem is that most do not know how to measure or define cleanliness nor can they recognize process problems related to residues. A new site specific method has been designed to run performance qualifications on boards built with specific soldering materials, reflow settings and cleaning methods. High impedance measurements are performed on break off coupons designed with components geometries used to build the assembly. The test method provides a gauge of potential contamination sources coming from the assembly process that can contribute to electrochemical migration.
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