Intermetallic compounds formed during diffusion soldering of Au/Cu/Al 2O3 and Cu/Ti/Si with Sn/In interlayer
Journal
Journal of Electronic Materials
Journal Volume
35
Journal Issue
7
Pages
1566-1570
Date Issued
2006
Author(s)
Abstract
A Si wafer was sequentially sputter-coated with Ti (20 nm), Cu (6 μm), Sn (4 μm), and In (4 μm). The specimen was then diffusion-soldered at temperatures between 150 and 300°C with an alumina substrate deposited with Cu (4 μm) and Au (6 μm). Experimental results showed that a multilayer of intermetallic phases with the compositions of (Cu0.99Au 0.01)6(Sn0.52In0.48)5/ (Au0.87Cu0.13)(In0.94Sn0.06) 2/(Au0.98Cu0.02) (In0.95Sn 0.05) formed at the Au/Cu interface. Kinetic analyses revealed that the growth of (Cu0.99Au0.01)6 (Sn 0.52In0.48)5 and (Au0.87Cu 0.13)(In0.94Sn0.06)2/(Au 0.98Cu0.02)(In0.95Sn0.05) intermetallics were diffusion-controlled with activation energies of 21.5 and 31.3 kJ/mol, respectively. Sound tensile strengths of 42 and 48 kg/cm 2 have been obtained under the bonding conditions of 150°C for 40 min. and 200°C for 30 min., respectively.
Type
journal article