A new nonepoxy liquid die attach adhesive

A novel imide adhesive system is presented. The new adhesive technology is solventless and thermosetting. This one-part, liquid adhesive offers excellent properties that make it suitable for microelectronics applications. Curing studies show the formation of a soft-baked polymer in as short a period as 60 seconds at 120°C. The soft-baked adhesive provides good adhesion and strength at room temperature. A post-curing step at 170°C for 60 minutes is necessary in order to obtained the ultimate adhesion strength. For dies that end up in plastic packages, the post-bake can be accomplished during the curing of the epoxy molding compound. One distinctive feature of this imide adhesive system is the excellent stability of the unreacted monomer mixture at room temperature, leading to unusually long pot life and the possibility of room temperature storage