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June 2003

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Subject:
From:
Brian Ellis <[log in to unmask]>
Reply To:
TechNet E-Mail Forum.
Date:
Mon, 2 Jun 2003 14:34:54 +0300
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Not an alternative one, Rudy, but complementary info:
a) The EDCF has some organics co-deposited with the foil, reducing the
density
b) the crystal growth is epitaxial, on the stainless steel drum,
starting where the oxide layer has minimal electrical resistance. As
this growth pattern ensures that the z-axis has a much more rapid
deposit than the sides of the crystals. This means that there are
hundred of micropores per mm2, at the crystal interfaces. These often
traverse the foil, even with thick foil. These also reduce the density.

Brian

Rudy Sedlak wrote:
> Does anyone except me and Joe Feldstadt remember why we use weight
> instead of thickness in measuring Copper??
>
> Copper foil used in making printed circuit boards is created by
> electroplating directly on to a roll, and peeled off as it is formed,
> thus it never sees a roller.  This plating process produces the surface
> we are all used to seeing on the roll side, but on the plating solution
> side, the surface is very rough and uneven.  This roughness makes it
> nearly impossible to measure the thickness, as it is different where
> ever you measure it.    So, we use weight, which gives us an average
> thickness....1 ounce/square foot = 1.3 mils = 1300 microinches.
>
> Seems a good way to get around the roughness issue...
>
> Anybody got an alternate?
>
> Rudy Sedlak
> RD Chemical Company---------------------------------------------------
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