Hi,

We are contemplating a device which will utilize wire bonding in a COB
arrangement. Could anyone suggest an appropriate thickness of the bond pad
for .001 dia Au wire? (Thermosonic or ultrasonic bonding, ball/wedge)

The device architecture is bulk Si, native SiOx, 1-2 micron spun dielectric
polymer, Cr adhesion layer (100 -300 angstroms), followed by an Au bond pad
layer. I have seen references to Au wire bond pad thickness in the 10k-15k
Angstrom range.

I have also seen references to a Cu layer as a diffusion barrier between the
Cr and Au. Does anyone have an opinion as to the need for a diffusion
barrier for Au wire bond pads?

Thank you in advance for your assistance.


Jeff Hawkins
Project Engineer
General Eastern Instruments