Silicone die bond adhesive and clean in-line cure for copper lead frame

Stress analysis by the finite-element method and a die bonding experiment were performed indicating that a die bond adhesive having a very low Young´s modulus is effective in reducing thermal stress. A silicone elastomer adhesive and an in-line cure process named the clean cure process were developed. In this process, the adhesive is cured quickly on a heat column, thus volatile organic species which affect the yield and reliability of devices are reduced significantly during cure. The bonding of large silicon dice to copper lead frames was successfully performed using this technology