Sintering silver paste material and method for bonding semiconductor chip
An object of the present invention is to provide a composition of a sintering Ag paste which can metallically bond to a nonprecious metal member with high strength as well as to a precious metal member, in a sintering Ag paste which metallically bonds to a metal at a low temperature, and to provide a bonding method to obtain a joint part having high strength. The sintering Ag paste is a material containing a solution of an organic silver complex that is easily decomposed by heat regardless of an atmosphere. Furthermore, the bonding method includes: metallizing a face of a nonprecious metal with Ag in a non-oxidizing atmosphere in a step prior to sintering Ag particles; and then sintering the Ag particles in an oxidizing atmosphere.
1. A sintering silver paste material comprising silver particles having an average particle size of 0.1 to 2.0 μm and an organic silver complex solution kneaded together into a slurry state, wherein the organic silver complex solution is a solution containing a liquid fatty acid silver salt compound or a solid fatty acid silver salt dissolved in an organic solvent having a boiling point of 150 ° C. or higher and comprising C, H and O, and a silver content in the organic silver complex solution is 30 wt % or more.
2. The sintering silver paste material according to claim 1 , wherein the paste material comprises 80 to 90 wt % of the silver particles; 5 to 20 wt % of the organic silver complex solution.
3. The sintering silver paste material according to claim 2 , wherein the paste material further comprises at least one kind of metallic particles selected from the group consisting of Ag, Cu, Al, Mg, Ni, Mo and W, having an average particle size of 5 to 500 μm.
4. The sintering silver paste material according to claim 2 , wherein the paste material further comprises particles having resin as a core, the surface of which is coated with a metal including at least one metal selected from the group consisting of Ag, Cu, Al, Mg, Ni, Mo and W.