New Equipment | Solder Paste Stencils
Simplify and Speed Up QFN and LGA device rework. StencilMate™ leadless device rework stencils make the process of reworking leadless devices such as QFNs and LGAs simple and fast. These adhesive-backed poyimide stencils are placed on to the bottom o
Electronics Forum | Wed Mar 21 16:32:03 EST 2001 | mparker
The root cause is dependant on the type of solder "splash", ball, whatever, that you are seeing post reflow. If it is smears, then cleaning the stencil underside is probably the answer. Are you using automatic wipers? How many print cycles between w
Electronics Forum | Wed Feb 14 08:15:08 EST 2007 | CK the Flip
I agree with Rob that voids are often times paste-dependent, and it's all about the type of flux that's used. The cause of the voids, as you all know, is outgassing of flux which has nowhere to go with BGA's. Some paste mfgrs. will recommend going
Industry News | 2016-09-15 18:08:04.0
Industry-leading associations IPC and SMTA jointly announce the High-Reliability Cleaning and Conformal Coating Conference, scheduled to take place October 25-27, 2016 at Hyatt Rosemont, Rosemont, Illinois. The conference is focused on best practices for designing, cleaning and coating highly dense electronic assemblies to assure reliability in today’s mobile society.
Industry News | 2011-08-18 21:23:09.0
For an industry that is constantly advancing, the technical conference at IPC Midwest Conference & Exhibition on September 21–22, in Schaumburg, Ill., will feature five sessions offering the latest research, methodologies and insights from industry experts to address critical challenges of manufacturing defect-free, quality electronics.
Technical Library | 2017-08-17 12:28:30.0
At SMT assembly, flux outgassing/drying is difficult for devices with poor venting channel, and resulted in insufficiently dried/burnt-off flux residue for no-clean process. Examples including: Large low stand-off components such as QFN, LGA Components covered under electromagnetic shield which has either no or few venting holes Components assembled within cavity of board Any other devices with small open space around solder joints
Technical Library | 2020-11-24 23:01:04.0
The miniaturization trend is driving industry to adopting low standoff components or components in cavity. The cost reduction pressure is pushing telecommunication industry to combine assembly of components and electromagnetic shield in one single reflow process. As a result, the flux outgassing/drying is getting very difficult for devices due to poor venting channel. This resulted in insufficiently dried/burnt-off flux residue. For a properly formulated flux, the remaining flux activity posed no issue in a dried flux residue for no-clean process. However, when venting channel is blocked, not only solvents remain, but also activators could not be burnt off. The presence of solvents allows mobility of active ingredients and the associated corrosion, thus poses a major threat to the reliability. In this work, a new halogen-free no-clean SnAgCu solder paste, 33-76-1, has been developed. This solder paste exhibited SIR value above the IPC spec 100 MΩ without any dendrite formation, even with a wet flux residue on the comb pattern. The wet flux residue was caused by covering the comb pattern with 10 mm × 10 mm glass slide during reflow and SIR testing in order to mimic the poorly vented low standoff components. The paste 33-76-1 also showed very good SMT assembly performance, including voiding of QFN and HIP resistance. The wetting ability of paste 33-76-1 was very good under nitrogen. For air reflow, 33-76-1 still matched paste C which is widely accepted by industry for air reflow process. The above good performance on both non-corrosivity with wet flux residue and robust SMT process can only be accomplished through a breakthrough in flux technology.
Events Calendar | Wed Apr 21 00:00:00 EDT 2021 - Wed Apr 21 00:00:00 EDT 2021 | ,
Oregon Chapter Tutorial: How Clean is Clean and How Do You Know for Sure?
SMTnet Express, July 20, 2017, Subscribers: 30,612, Companies: 10,637, Users: 23,528 Reactivity Of No-Clean Flux Residues Trapped Under Bottom Terminated Components Bruno Tolla, Ph.D., Jennifer Allen, Kyle Loomis - Kester Corporation , Mike
ASYMTEK Products | Nordson Electronics Solutions | https://www.nordson.com/en/divisions/efd/products/thermal-compounds/thermal-compound
Lubrication Systems Mixers Pest Control Systems Reservoirs and Pumps Solder Paste and Flux Syringe Barrels and Cartridges Thermal Compounds (TIM) Two-Component (2k
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