This online PDF paper reviews the technology of release and issues
relating to surface tension and beams adhering to the substrate.

http://www.appliedmst.com/pdf/references/ssr_Maboudian.pdf

Besides the methods of dilution with alcohols, another method is to
freeze the immersed solution and then do a sublimination in a vacuum.

HOWEVER, the real problem is that your CPD equipment is broken and it
needs to be fixed. Someone at your institution needs to do his or her
job and fix it. Other people need to stop accepting excuses from your
maintenance people for not getting it fixed.

You should start investigating the machine and read the manual and
making inquiries. You should call the vendor, send the vendor write ups
of what you observed, etc. Read blueprints, drawings, etc. Take
measurements.

This will get maintenance somewhat concerned that you might actually fix
it before they do, and you really might fix it before they do. Even if
you are bewildered by the cause, persist and act as if you might find
the cause shortly. The motivating threat is that you will find the cause
and have a fix before the people who are paid to fix the equipment do
and they will be revealed to be ineffectual.

You will first get from maintenance a lot of reasons why it is hopeless
from the maintenance person to get you to give up. Ignore their sob
stories. When you are not dissuaded, and persist, it will often get the
person motivated to get moving and earn his or her wage and get it fixed
before you do. The basic thing is to persist. A lot of problems are not
one quarter as difficult as they seem to be.

If they do fix it, you will have to listen to a story about how it was a
great obstacle and they overcame it. Be polite and pretend you accept
the story no matter how obvious it was that it was a simple thing to
fix.

A lot of maintenance people are good, but learning to prod lazy
maintenance people to do their job is worth any three graduate level
courses at the university.

Basically it comes down to this, either maintenance can fix it, or they
can't. If they can't fix equipment, they are a needless cost.

Ed





-----Original Message-----
From: mems-talk-bounces@memsnet.org
[mailto:mems-talk-bounces@memsnet.org] On Behalf Of lin yu
Sent: Friday, November 06, 2009 1:01 PM
To: mems-talk@memsnet.org
Subject: [mems-talk] Replacement of critical point drying


Hi all,

I'm trying to suspend a beam structure with 150nm wide and 10um long
with critical point drying process. However, our CPD equipment is very
violent while introducing liquid CO2. After this process, all the
suspended beams are gone. So I was wondering if there's a possible
replacement of CPD process to suspend beam structures. I heard that
people use some kind of low surface tension liquid and air dry the
samples. Does anyone have experience on this? Any suggestion is
appreciated.

Thanks,
Lin