Policy on nanotubes, nanowires, etc.

Mary Tang mtang at stanford.edu
Thu Oct 23 08:31:51 PDT 2008

Hi John --

Our policy on nanotubes has been that:

1.  Conducting and semiconducting nanoparticles and nanowires cannot be 
spun in from solution inside the lab.  This is to prevent 
cross-contamination of other people's work, since spin coating 
aerosolizes the solution.  Ordinary latex nanoparticles are OK on the 
headway, because they are non-conductive and can be dissolved like most 
resists.  We have a rather crude spin coater outside the lab which is 
available for spin coating of conductive materials.  There are some 
nicer ones in CPIMA, MatSci and ME labs.

2.  Wafers with nanoparticles and nanowires adhered to them can 
generally be processed as "gold-contaminated" substrates.  As you say, 
van der Waals holds them down through most processing, including spin 
coating with photoresist.  So, the processing you propose should be fine 
for the most part.  The only question I have is with the ASML.  As you 
know, the ASML system belongs to ASML, and they have the final word as 
to what kind of materials are OK to process in their tool.  Ed -- have 
nanotubes been OK'ed on the ASML?


John Ross Jameson wrote:
> Dear SpecMat,
> I'd like to do some processing of carbon nanotubes and nanofibers
> in SNF, and I've gotten different answers about what is allowed
> and what isn't.  What I'd like to do is bring wafers into the fab
> that have carbon nanotubes or nanofibers sitting horizontally on
> the surface.  The nanotubes/fibers would only be held on by van der
> Waal forces.  That is enough to keep them from blowing off, but
> not enough to keep them from being rubbed off.  I'd like to do a
> lift-off process to pattern metal on top of the nanotubes/fibers,
> using either the ASML or EV aligner.  For the metal dep, I'd use
> the innotec or metalica.  The lift-off could be done at SNF, or
> elsewhere if necessary.
> Would this process be OK to do in SNF?  Do I need to check back with
> you if I decide to try another type of nanotube/wire?
> Thank you,
> John

More information about the specmat mailing list