Kathy,

Back in the olden days, before I was born, they discovered that silver
had a nasty habit of forming dendrite-like fingers that would create
shorts over time. That is part of the reason they stopped pursuing
pressed silver powder circuitry (please someone correct me if I'm
wrong).

The conditions that caused the migration were high humidity (like
Louisiana) and a potential difference (like applied voltage).

There was also a silver solubility issue with the ancient solders of
old.


Hope this is of some help. Someone please advise me if this isn't so.

Jonathan

-----Original Message-----
From: Kathy Palumbo [mailto:[log in to unmask]]
Sent: Wednesday, March 24, 1999 2:10 PM
To: [log in to unmask]
Subject: [TN] Silver Migration


Can anyone help me?

> I have been told by a chip component manufacturer that the reason they
> changed the pin out on a resistor network from a concave to a convex was
> because it allowed them to place the pin terminations farther away from
> one another, which in turn helped to reduce the issue of silver migration.
>
> My questions are:
>
> 1.  What are the conditions that silver migration can occur?
>
> 2.  Could these conditions be present in chip components, particulary
> resistor array networks?
>
> 3.  Has anyone ever heard of this or had issues with this?
>
> 4.  Is there any supporting research to back this claim?
>
> Thanks in advance for you support.
>
> Kathy Palumbo

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