Issue link: https://iconnect007.uberflip.com/i/634491
32 SMT Magazine • February 2016 a reflow oven where both are soldered to the substrate. This assembly process requires a "two-print stencil" printing procedure and requires two in- line stencil printing machines. Normally, flux is printed first using a thin electroform stencil (40–50 µm thick) to print flux on the FC die pads. This is referred to as the "first print sten- cil." Immediately after the first print, the sub- strate is advanced to the second printer. The "second print stencil" is used to print solder by William Coleman pHoTo STENcil llc Mixed technology packages that have both flip chip (FC) and surface mount devices (SMD) on the same substrate are now being assembled in a normal SMT assembly process. Instead of dipping the FC die in flux, both flux and paste are printed on the substrate. Then the FC and SMD are placed into the paste/ flux with pick-and-place equipment and sent to two-Print stencil solutions for Flip chip/smt assembly Figure 1: Solder paste aperture for 01005 and relief pocket for flux. Feature sHort