Patent ID: 8753983

Claim:
A method for forming a semiconductor device using a silicon-containing die having a first surface and a heat sink having a substrate having a first surface, comprising: forming a barrier layer comprising cobalt and nickel over the first surface of the heat sink; forming a palladium layer on the barrier layer; forming a first gold layer on the palladium layer; forming a second gold layer on the first surface of the silicon-containing die; and bonding the silicon-containing die to the heat sink, wherein the bonding comprises: joining the silicon-containing die and the heat sink such that the first gold layer and the palladium layer are between the first surface of the silicon-containing die and the first surface of the heat sink; and heating the first gold layer and the palladium layer to form a die attach layer between the first surface of the silicon-containing die and the first surface of the heat sink, the die attach layer comprising a gold interface layer having a plurality of intermetallic precipitates, each of the plurality of intermetallic precipitates comprising nickel, cobalt, palladium, gold, and silicon.