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Bob:<br>
<br>
This is a good point that reminds me of minor etch modifications
that our etch guru Jim McVittie made me aware of:<br>
<br>
<blockquote type="cite">
<pre wrap="">John,
The STS process engineer from the factory who trained me on STS2 said that they gone to adding some O2 to the etch steps on there old tools to solve the vacuum line deposition problem. We never went that way because it meant that we would have to recharacterize our processes on the STS1 and no one wantd to do it. The Berkeley folks published a paper on adding O2. Jim
</pre>
</blockquote>
I'm hopeful that someone from Berkeley can provide a better
reference and comment on this approach, but I believe that folks
have found that adding modest oxygen flow (~10%, as I recall) during
the etch step helps to reduce polymer buildup without significantly
affecting etch rates and other process parameters.<br>
<br>
Thanks,<br>
<br>
John<br>
<br>
<br>
On 11/5/2013 2:16 PM, Bob Henderson wrote:
<blockquote
cite="mid:000c01ceda74$a21b6950$e6523bf0$@henderson@etchedintimeinc.com"
type="cite"><span style="font-size: 11pt; font-family:
"Calibri","sans-serif"; color: rgb(31, 73,
125);">Has anyone considered using an oxygen/fluorine plasma for
removal of the polymer. Since most DRIE systems have an ICP
source a fair amount of O/F will be generated that can be used
to etch away the carbon rich polymer maybe as far as the gate
valve and turbopump. The reactive species probably won’t have a
lifetime that will extend very far down the foreline but I have
seen downstream plasmas that will go a few feet into the
foreline before extinguishing. Bob Henderson</span></blockquote>
<br>
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