Resin-Molded Circuit Package Capable of Preventing Resin Cracking During Soldering
Original Publication Date: 1988-May-01
Included in the Prior Art Database: 2005-Feb-15
In resin-molded flat packages in which a silicon chip is mounted on a lead frame island and encapsulated by resin, such as epoxy, moisture trapped between the back side of the island and the resin vaporizes during soldering, particularly vapor phase soldering, to generate a high vapor pressure, thereby causing the resin to crack. The present package prevents such resin cracking by improving the bonding between the island and the resin. Fig. 1 shows the present plastic flat package structure. Silicon chip 10 is attached on lead frame island 12 by die bonding paste 14, such as Ag epoxy or Ag polyimide. Many small holes 16 are formed in the island 12, as shown in Fig. 2.