J Provine jprovine at
Fri Oct 15 17:04:57 PDT 2010

dear specmat,
project to convert savannah line to allow room air introduction for oxygen
source to oxidize substrates in chamber (part of EE412 project).

to perform this i will shut off the NH3 source bottle and regulator...empty
the line connecting source to the savannah manifold by purging the line by
ald valve actuation.  this will pull any residual NH3 through the system to
the pump and out through scrubbed exhaust to same as during deposition
operation.  when no discernable pressure delta vs baseline is observed the
line is empty enough to disconnect.  the line will be disconnected at the
needle valve which supplies a restricted flow orifice prior to the ald
valve.  for there the needle valve and ald valve serve as the intake
restriction for the introducing room air into the chamber.  we'll check the
pressure pulses and adjust the input of room air to an appropriate amount
based on ald valve actuation time and needle valve setting.  an additional
particle filter may be necessary to connect via VCR to the needle valve.

the need for the oxygen source is on a per run basis.  as that run is
finished the NH3 bottle will be reconnected to the needle valve with a fresh
VCR gasket. and the line will be purged into an empty chamber first with the
regulator closed, then open to ensure that we have retrieved the NH3
precursor pulses seen before.

advice or maintenance assistance as described by mary below is welcome.


On Fri, Oct 15, 2010 at 4:53 PM, Mary Tang <mtang at> wrote:

> Hi J --
> Thanks.  John needs to decide -- and this could precipitate it.  As a
> start, could we treat this sort of like a specmat request?  Could you just
> write up a brief statement of what you need to do, for the record?  Spec mat
> emails are archived.
> M
> J Provine wrote:
>> Mary,
>> Please let me know which maintenance person should be involved and
>> I'll coordinate with them.
>> J
>> On Friday, October 15, 2010, Mary Tang <mtang at> wrote:
>>> Hi J --
>>> I meant to ask you earlier but it slipped my mind....   If I understand
>>> correctly, you had mentioned in the EE412 class plans to disconnect the NH3
>>> line from the Savannah to install a line filter to allow room air to serve
>>> as the oxygen source....  Are you working with one of the maintenance staff
>>> on this?  I'd just like to make sure that there are no safety concerns.  We
>>> should generally have two levels of safety for any potentially hazardous
>>> operation, and I'm not sure we've got this on the Savannah right now.
>>>  Presuming this hasn't been done yet, please do work with us to get this
>>> done in a safe a manner as possible.  Let us know.
>>> Thanks,
>>> Mary
>>> --
>>> Mary X. Tang, Ph.D.
>>> Stanford Nanofabrication Facility
>>> CIS Room 136, Mail Code 4070
>>> Stanford, CA  94305
>>> (650)723-9980
>>> mtang at
> --
> Mary X. Tang, Ph.D.
> Stanford Nanofabrication Facility
> CIS Room 136, Mail Code 4070
> Stanford, CA  94305
> (650)723-9980
> mtang at
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