> Is it true that Ag exhibits poor adhesion to Si, say for example, in
> comparison to Al?  Will a thin layer of Cr help to improve this adhesion?
> Finally, are there other straightforward methods to promote adhesion of
> these materials?

Standard IC packaging stacks for Silver usually follow the "adhesion
layer" - "intermetallic barrier" - "bond metal" scheme, e.g.
Ti - Ni - Ag or Cr - NiV - Ag.
The two most straightforward methods to promote adhesion without
any underlayers are:
a1) bring the substrate in "as clean as possible"
a2) if possible, roughen up the surface a bit (sputter etch)
b) keep substrate temperature as low as possible

regards
klaus
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