Electronics Forum | Thu Jul 20 03:00:53 EDT 2006 | reypal
If you are using SMT machine for component placement you may check your nozzle where in some cases solder paste stuck to it and during placement will easily get into gold pad area. otherwise you have use kapton tape in order not to expose those pads.
Electronics Forum | Wed Apr 05 20:52:51 EDT 2006 | davef
If you let the silver content of your solder connections get much above 3 percent, it could cause reliabilitility problems, similar to the problems caused when the gold content gets too high.
Industry News | 2021-02-25 13:41:10.0
MacDermid Alpha Electronics Solutions, leaders in innovative electronic interconnect technologies, will feature their recent product releases and latest innovations, at the IPC APEX Virtual Conference and Expo, March 8-12, 2021.
Industry News | 2024-02-26 14:00:02.0
High-performance memory supplier chooses Saki's 3Si solder-paste inspection and 3Di inline AOI systems to handle miniaturization challenges and prepare for smart manufacturing.
Technical Library | 2018-09-26 20:33:26.0
Bottom terminated components, or BTCs, have been rapidly incorporated into PCB designs because of their low cost, small footprint and overall reliability. The combination of leadless terminations with underside ground/thermal pads have presented a multitude of challenges to PCB assemblers, including tilting, poor solder fillet formation, difficult inspection and – most notably – center pad voiding. Voids in large SMT solder joints can be difficult to predict and control due to the variety of input variables that can influence their formation. Solder paste chemistries, PCB final finishes, and reflow profiles and atmospheres have all been scrutinized, and their effects well documented. Additionally, many of the published center pad voiding studies have focused on optimizing center pad footprint and stencil aperture designs. This study focuses on I/O pad stencil modifications rather than center pad modifications. It shows a no-cost, easily implemented I/O design guideline that can be deployed to consistently and repeatedly reduce void formation on BTC-style packages.
Technical Library | 2023-08-04 15:27:30.0
A designed experiment evaluated the influence of several variables on appearance and strength of Pb-free solder joints. Components, with leads finished with nickel-palladium-gold (NiPdAu), were used from Texas Instruments (TI) and two other integrated circuit suppliers. Pb-free solder paste used was tin-silver-copper (SnAgCu) alloy. Variables were printed wiring board (PWB) pad size/stencil aperture (the pad finish was consistent; electrolysis Ni/immersion Au), reflow atmosphere, reflow temperature, Pd thickness in the NiPdAu finish, and thermal aging. Height of solder wetting to component lead sides was measured for both ceramic plate and PWB soldering. A third response was solder joint strength; a "lead pull" test determined the maximum force needed to pull the component lead from the PWB. This paper presents a statistical analysis of the designed experiment. Reflow atmosphere and pad size/stencil aperture have the greatest contribution to the height of lead side wetting. Reflow temperature, palladium thickness, and preconditioning had very little impact on side-wetting height. For lead pull, variance in the data was relatively small and the factors tested had little impact.
Manufacturability & Reliability Challenges with Leadless Near Chip Scale (LNCSP) Packages in Pb-Free Processes Manufacturability & Reliability Challenges with Leadless Near Chip Scale (LNCSP) Packages in Pb-Free Processes by: Cheryl Tulkoff, Greg
Manufacturability & Reliability Challenges with Leadless Near Chip Scale (LNCSP) Packages in Pb-Free Processes Manufacturability & Reliability Challenges with Leadless Near Chip Scale (LNCSP) Packages in Pb-Free Processes Leadless, near chip scale
Heller Industries Inc. | https://hellerindustries.com/intermetallics-growth/
. During reflow, with the addition of tin-lead solders, the intermetallic grows. With other board metal finishes, other metallics form, such as AuSn when soldering components to boards with gold-flash finish (and tin-lead solder
| http://etasmt.com/cc?ID=te_news_bulletin,23575&url=_print
. During reflow, with the addition of tin-lead solders, the intermetallic grows. With other board metal finishes, other metallics form, such as AuSn when soldering components to boards with gold-flash finish (and tin-lead solder
COT specializes in high quality SMT nozzles and consumables for pick and place machines. We provide special engineering design service of custom nozzles for those unique and odd components.
2481 Hilton Drive
Gainesville, GA USA
Phone: (770) 538-0411
.gif)
