Technical Library | 2023-01-17 17:27:13.0
Reflow profile has significant impact on solder joint performance because it influences wetting and microstructure of the solder joint. The degree of wetting, the microstructure (in particular the intermetallic layer), and the inherent strength of the solder all factor into the reliability of the solder joint. This paper presents experimental results on the effect of reflow profile on both 63%Sn 37%Pb (SnPb) and 96.5%Sn 3.0%Ag 0.5%Cu (SAC 305) solder joint shear force. Specifically, the effect of the reflow peak temperature and time above solder liquidus temperature are studied. Nine reflow profiles for SAC 305 and nine reflow profiles for SnPb have been developed with three levels of peak temperature (230 o C, 240 o C, and 250 o C for SAC 305; and 195 o C, 205 o C, and 215 o C for SnPb) and three levels of time above solder liquidus temperature (30 sec., 60 sec., and 90 sec.). The shear force data of four different sizes of chip resistors (1206, 0805, 0603, and 0402) are compared across the different profiles. The shear force of the resistors is measured at time 0 (right after assembly). The fracture surfaces have been studied using a scanning electron microscopy (SEM) with energy dispersive spectroscopy (EDS)
Technical Library | 2023-01-17 17:22:28.0
The impact of voiding on the solder joint integrity of ball grid arrays (BGAs)/chip scale packages (CSPs) can be a topic of lengthy and energetic discussion. Detailed industry investigations have shown that voids have little effect on solder joint integrity unless they fall into specific location/geometry configurations. These investigations have focused on thermal cycle testing at 0°C-100°C, which is typically used to evaluate commercial electronic products. This paper documents an investigation to determine the impact of voids in BGA and CSP components using thermal cycle testing (-55°C to +125°C) in accordance with the IPC- 9701 specification for tin/lead solder alloys. This temperature range is more typical of military and other high performance product use environments. A proposed BGA void requirement revision for the IPC-JSTD-001 specification will be extracted from the results analysis.
Technical Library | 2023-01-17 17:25:14.0
BTC Void Reduction For Yield and Performance Enhancement
Technical Library | 2023-01-17 17:54:56.0
This paper describes the new flux management systems that Heller Industries introduced in 1999.
Technical Library | 2023-01-17 17:29:40.0
A Practical Investigation into the Use of No Lead Solders for SMT Reflow
Technical Library | 2023-01-17 17:49:30.0
Repeatability of the Temperature Profile under Load Variation
Technical Library | 2023-01-17 18:00:39.0
EQUIPMENT SUPPLIERS HAVE BECOME A RESOURCE FOR PROCESS CONTROL EXPERTISE, EVEN IN THE REFLOW OPERATION.
Technical Library | 2020-01-28 00:23:58.0
This paper explores new advances in the reflow soldering process including vacuum technology and warpage mitigation systems. The first topic for discussion will be the implementation of a vacuum process directly in a conventional inline soldering system. The second topic presented is the mitigation of warpage on substrates or wafers.
Technical Library | 2023-01-17 17:35:07.0
After years of concentration on resolving productivity- related concerns such as increasing speed, consistency and throughput while reducing costs, many of the world's leading electronics manufacturers have added a new mandate to their agendas. They are seeking to minimize the environmental impacts of their assembly processes and final products without sacrificing the high levels of productivity and quality that have been achieved through decades of effort.
