Plastic/Metal Lead Frame for Dual Inline Edge-Connected Package
Original Publication Date: 1986-Nov-01
Included in the Prior Art Database: 2005-Mar-09
This article describes a method for encapsulating a ceramic substrate with chips mounted on both faces using dual inline edge-connected module (ECM) techniques. Fig. 1 shows a typical lead frame 10 with a plastic base and copper pins 11 encapsulated in the base. A hole in the plastic base 12 receives the formed end of pin 11 to make up spring clip 13. The other end of the pin 11 is straight. The lead frame is affixed to a ceramic substrate 14 by soldering the spring clip 13 to the edge connections 15 fabricated on the substrate. By using this method to affix the lead frame to the substrate, both the spring clip contact (mechanical) and the surface solder bond connection (metallurgical) reinforce each other to insure a high degree of contact reliability. Fig.