Bill,

Thanks for the response. The pH values can range up to 12.
I've heard of turning surface hydrophobic by microstructuring using laser, but
so far I could find some works only with plastic materials, not with Si. Any
idea?

Natsuki

-----Ursprüngliche Nachricht-----
Von: mems-talk-bounces@memsnet.org [mailto:mems-talk-bounces@memsnet.org] Im
Auftrag von Bill Moffat
Gesendet: Dienstag, 17. November 2009 19:45
An: General MEMS discussion
Betreff: Re: [mems-talk] Turning Si surface hydrophobic

Natsuki,

        YES to 1 contact angles much greater than 70 simple chemical work gives
up to 130.  Yes to 2 at room temperature dependent upon chemistry I have 5 year
old microscope slides that have a contact angle of 103.  The same as when we
produced them 5 years ago, they have been sitting on my desk for the last 5
years.  Do not know about the thermally stable at 800-900 C we have never been
tested that high.  This could be the reason some of our customers are asking for
high temperature chemical delivery systems.  Chemically stable within reason in
alkaline solutions what PH?.  Bill Moffat