Technical Library | 2021-10-20 18:21:06.0
The solderability of the SAC305 alloy in contact with printed circuit boards (PCB) having different surface finishes was examined using the wetting balance method. The study was performed at a temperature of 260 _C on three types of PCBs covered with (1) hot air solder leveling (HASL LF), (2) electroless nickel immersion gold (ENIG), and (3) organic surface protectant (OSP), organic finish, all on Cu substrates and two types of fluxes (EF2202 and RF800). The results showed that the PCB substrate surface finish has a strong effect on the value of both the wetting time t0 and the contact angle h. The shortest wetting time was noted for the OSP finish (t0 = 0.6 s with EF2202 flux and t0 = 0.98 s with RF800 flux), while the ENIG finish showed the longest wetting time (t0 = 1.36 s with EF2202 flux and t0 = 1.55 s with RF800 flux). The h values calculated from the wetting balance tests were as follows: the lowest h of 45_ was formed on HASL LF (EF2202 flux), the highest h of 63_ was noted on the OSP finish, while on the ENIG finish, it was 58_ (EF2202 flux). After the solderability tests, the interface characterization of cross-sectional samples was performed by means of scanning electron microscopy coupled with energy dispersive spectroscopy.
Technical Library | 2016-05-05 15:19:39.0
For many years, manufacturing has sought to increase competitiveness by moving off-shore to countries with lower labour costs. Electronic manufacturing services (EMS) companies provided an essential element to make off-shore transfer happen more quickly, offering further cost reduction opportunities from load balancing. Fierce arguments were put forward to protect the loss of local jobs, although the result was, in almost all cases, inevitable. Today, however, the whole market of PCBbased electronics products has changed significantly. The "pros" of off-shoring are no longer what they once were, and the "cons" are becoming more significant because off-shore manufacturing can no longer satisfy the needs of the market. In this paper, we expose the real costs of off-shore manufacturing, and put labour cost differentials into perspective. We demonstrate how practically, using existing technologies, re-shored manufacturing can yield better business return, either for an OEM, or through EMS providers.
