RECESSED IC SUBSTRATE FOR TUNING PAD CONTAINMENT
Original Publication Date: 1991-Jul-01
Included in the Prior Art Database: 2001-Dec-12
This paper and the following sketches describe a unique means for containment of IC tuning pads with- out reflow interference. The outputs of various IC's are drifting during the current packaging process. To increase yields, the IC's may be tuned subsequent to the packaging process. In order to tune these It's, additional pads (figure 3) on the substrate surface are required. These pads must not contact PC board run- ners or have the opportunity to short to the printed wiring board during reflow. The present method of insulating these pads requires a 2-4 mil thick material such as polyimide pressure sensitive tape (figure 1) on the underside of the IC substrate. This means of electri- cal insulation could inhibit proper reflow characteristics.