Disclosed herein is a system and method for mounting semiconductor packages by forming one or more interconnects, optionally, with a wirebonder, and mounting the interconnects to a mounting pad on a target package. Mounting the interconnect may comprise ultrasonically welding the interconnects to the mounting pads, and the interconnect may be mounted via a mounting node on the end of the interconnect, wherein the mounting node may be formed by an electric flame off process. The interconnects may be trimmed to one or more substantially uniform heights, optionally using a laser or contact-type trimming system, and the tails of the interconnects may be supported during trimming. A top package may be bonded on the trimmed ends of the interconnects. During mounting, a support plate may be used to support the package, and a mask maybe used during interconnect mounting.