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<p>Dear Network,</p>
<p>I have a big copper sputter target holder on which a WO3
(tungsten tri-oxide) target on it. I'd like to etch away the WO3
and keep the copper. Anyone can recommend some appropriate wet
chemistry?</p>
<p>Best <br>
</p>
<p>Mario<br>
</p>
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<img src="cid:part1.TThQai7o.Jsse2Q1l@physics.ubc.ca" border="0"></div>
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