Improved Ball Limiting Metallurgy Pad Structure for Device Solder Bond
Original Publication Date: 1980-Oct-01
Included in the Prior Art Database: 2005-Feb-13
The ball limiting metallurgy pad 10, illustrated on device 12 having a passivating dielectric layer 14 on the surface, has a lower layer 16 of chromium with a thickness in the range of 0.8 to 2k angstroms, and an overlying layer 18 of platinum having a thickness in the range of 3 to 5k angstroms. The adhesion of layer 16 to oxide layer 14 is excellent. The adhesion of platinum layer 18 to the chromium layer 16 is also strong and does not require a phasing operation.