I'm a little contrarian on this.  I've produced highly hydrophobic
(easily greater than 110 deg contact angle) FOTS films on silica
surfaces using a highly dilute FOTS-alcohol-water-acid solution, 10s
dip, 5 min 90C cure (RT cure works too).  There may be polymerized FOTS
left but this is never bound and is easily removed in an ultrasonic
bath, with very gentle mechanical cleaning or with a blow off approach.
It's possible to completely avoid FOTS precipitation but the dip process
is more complicated.

One problem with this (dip) approach on a highly complex surface, say
micro channels, is that the surface may not completely wet out leaving
some regions uncoated.

This process is patented and the patent shouldn't be too hard find.

-----Original Message-----
From: [email protected]
[mailto:[email protected]] On Behalf Of Marco Doms

As FDTS reacts vigorously with water, a dry atmosphere is quite useful.
I
have always used a normal laminar flow hood in a dry environment and
tried
to act as quickly as possible.
Why do you want to do a dipping process? A vapor phase deposition is
faster, not more complicated and gives better results!