[Fwd: New Chemical Request: Perfluorooctyl-trichloro-silane]
mtang at stanford.edu
Tue Feb 14 12:00:39 PST 2006
Oops. I don't think we did answer it. I think it's OK from a safety
perspective, especially in the small amounts described here. But I
still do prefer the -ethoxy and -methoxy versions of these chemicals
over the -chloro versions. The only possible problems I see are that
the dessicator will be coated with this anti-sticking stuff (is that a
problem? I'm not sure what else the dessicator is used for. It will
mean that if there is cross-contamination, the problem will be stuff not
sticking to substrates) and that the -chloro versions of these compounds
tend to react quickly with any moisture in the air to polymerize into
My suggestion is that if we are concerned with cross-contamination that
we have a dedicated dessicator for anti-sticking processes (as I also
think that nanoimprint might need something like this anyway.) It's a
couple hundred dollars
(http://www.jenconsusa.com/products_specs_1.cfm?id=26). It might be a
good idea to have one dessicator for hydrophobic processing and another
for hydrophillic processes.
Mahnaz Mansourpour wrote:
> I am forwarding this to specmatt , not knowing if we have answered it
> or not?
> -------- Original Message --------
> Subject: New Chemical Request: Perfluorooctyl-trichloro-silane
> Date: Fri, 27 Jan 2006 17:04:01 -0800
> From: Neville Mehenti <nmehenti at stanford.edu>
> To: specmat at snf.stanford.edu
> CC: nmehenti at stanford.edu
>I would like to make a request to bring a new chemical into the cleanroom
>for use in a process.
>Below this email is the requested information for this new chemical
>request, as outlined on the SNF website.
>Please let me know if there is a problem or if you would like any more
>Thanks very much and hope to hear from you soon.
>1. Name: Neville Mehenti; Coral: mehenti; Tel: (650)723-1669; Email:
>nmehenti at stanford.edu, PI: Prof. Stacey F. Bent
>2. Full Name: 1H,1H,2H,2H-Perfluorooctyl-trichloro-silane (CAS 78560-45-9)
>The MSDS is attached with this email as a pdf file.
>3. Manufacturer: Sigma-Aldrich
>3050 Spruce Street, St. Louis, MO 63103; Tel: 314.771.5765; Website:
>4. The reason I am requesting to bring this material into the lab is
>because I am looking to spin thin (10-20 microns) silicone membranes on a
>silicon-photoresist mold, and then peel them off to serve as components for
>microfluidic devices. I have been using polydimethylsiloxane (PDMS) as the
>membrane material, but the membranes are not strong enough to resist
>tearing or stretching upon removal from the mold. I have found that
>treatment of these molds by exposing them to this requested chemical under
>vacuum allows for easier release of the membrane from the mold with minimal
>stretching. By silanizing the silicon-photoresist mold with this chemical,
>the surface of the mold is effectively "teflonized," thus preventing any
>strong interaction between the PDMS and the mold. I would prefer to do
>this process at the fab so that my molds remain in a clean environment
>(since I have had particulate problems when silanizing in my normal lab and
>this creates several problems with the resulting membranes).
>5. I plan on using this chemical only in the desiccator above the
>Headway. I will place my silicon photoresist molds along with a small
>volume (~100 microliters) of the chemical in the desiccator and pull house
>vacuum on it for one hour, thus forming silane vapor which will
>subsequently react to the native oxide on the mold. I will then spin PDMS
>on these molds using the Headway, and they will then require no further
>processing within SNF.
>6. For each time I silanize my molds, I will be using ~100 microliters of
>this chemical, which is in liquid form. Only a small fraction of this
>volume will be vaporized to properly silanize the surface of my molds.
>7. I will carefully bring in the appropriate volume (~100 microliters) of
>the chemical into SNF each time I need to use it. The chemical will be
>stored in a labelled 1-ml glass vial, and will be brought in within a
>larger vial as a secondary container. When placed in the desiccator, I
>will remove the cap from the vial and place the vial in one of my beakers
>(in order to stabilize the vial from falling due to a bump or rapid
>8. After the silanization process, I will put the cap back on the vial,
>and place this vial back in the secondary container. These vials will be
>removed from the fab and I will dispose of it properly within my regular
>lab as hazardous waste.
Mary X. Tang, Ph.D.
Stanford Nanofabrication Facility
CIS Room 136, Mail Code 4070
Stanford, CA 94305
mtang at stanford.edu
More information about the specmat