Electronics Forum | Fri Apr 23 08:20:25 EDT 2004 | babe
Sometimes solder balling is related to oxidized paste or paste that has sat on the pcb too long before reflow. Mostly it is related to process, sorry... Too slow or too fast of a reflow ramp rate. Heating up an assembly too quickly will not allow the
Electronics Forum | Wed Jun 23 11:47:48 EDT 1999 | Dave F
| In a month or so, we will be getting an in-line x-ray inspection machine. It will require that we solder our most comlicated side (normally top) first. This is opposite to our process now where we solder our passive (bottom) side first. We cann
Industry News | 2011-08-30 19:41:37.0
The SMTA announced two sessions on Alternate Lead-Free Alloys featured during their annual conference, SMTA International, taking place October 16-20, 2011 in Ft. Worth, Texas.
Industry News | 2021-06-15 04:44:00.0
The SMTA is pleased to announce that registration for the International Conference for Electronics Hardware Enabling Technologies (ICEHET) is open with on-demand access available until September 1, 2021.
Technical Library | 2023-01-17 17:12:33.0
Reflowed indium metal has for decades been the standard for solder thermal interface materials (solder TIMs or sTIMs) in most high-performance computing (HPC) TIM1 applications. The IEEE Heterogeneous Integration Thermal roadmap states that new thermal interface materials solutions must provide a path to the successful application of increased total-package die areas up to 100cm2. While GPU architectures are relatively isothermal during usage, CPU hotspots in complex heterogeneously-integrated modules will need to be able to handle heat flux hotspots up to 1000W/cm2 within the next two years. Indium and its alloys are used as reflowed solder thermal interface materials in both CPU and GPU "die to lid/heat spreader" (TIM1) applications. Their high bulk thermal conductivity and proven long-term reliability suit them well for extreme thermomechanical stresses. Voiding is the most important failure mode and has been studied by x-ray. The effects of surface pretreatment, pressure during reflow, solder flux type/fluxless processing, and preform design parameters, such as alloy type, are also examined. The paper includes data on both vacuum and pressure (autoclave) reflow of sTIMs, which is becoming necessary to meet upcoming requirements for ultralow voiding in some instances.
Technical Library | 2018-11-20 21:33:57.0
There are several industry-accepted methods for determining the reliability of flux residues after assembly. The recommended methods of test sample preparation do not always closely mimic the thermal cycle experienced by an assembly. Therefore, extraction from actual assemblies has become a popular method of process control to assess consistency of post-reflow cleanliness. Every method of post-reflow flux residue characterization will depend on the reflow process followed to prepare the coupon.This investigation will focus on the effect of thermal conditions on the remainder of active ingredients in flux residues after assembly with no-clean solder pastes.
Professor Ron Lasky, Ph.D., Phil Zarrow, and Jim Hall discuss the SMT Processes Certification offered by SMTA. http://www.smta.org/certification/ Video production courtesy of Indium Corporation.
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