Cleaning gratings
Calibration gratings are often needed to verify Scanning Probe equipment's accuracy and to check tip integrity. But over time, these gratings become contaminated with debris, either organic matter, dust, and even from the equipment itself (who hasn't crashed an AFM tip onto the surface during engagement?).
Below are some cleaning methods for such gratings, with some suggestions given in the SPMNewsgroup (September 2009).
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CO2 Snow Cleaning
"...involves ballistic/hydrodynamical impact and large temperature gradient."
See : Applied Surface Technologies
The manufacturer's web site includes a page related specifically to AFM.
This method has had positive responses from Newsgroup members.
Replicating Tape / PDMS Resin
This method of cleaning involves covering the grating with a "goop" which entraps the debris on the surface and is subsequently peeled off. Results might be good on large, loose particulate.
"I wonder if replicating tape might work for you, available from SEM supply sources
(e.g., SPI). Place on surface and use acetone to soften and allow it to form over
the topography. Once it cures ( a few minutes) peel it off and it can remove lots
of crud."
Greg Clark <GWClark@manchester.edu>
"...Polydimethylsiloxane (PDMS) resin is used for micro-printing..."
Igor Sokolov" <isokolov@clarkson.edu>
The latter is used in nanoimprinting and replica molding (see work of Whitesides )
Plasma Cleaning
"..Plasma cleaning involves the removal of impurities and contaminants from surfaces through the use of an energetic plasma created from gaseous species... Plasma cleaning is a commonly used process in the semiconductor industry which has the advantage of being solvent free, thus producing less waste..."
From http://en.wikipedia.org/wiki/Plasma_cleaning
The mechanism of plasma cleaning might besimilar to CO2 method listed above.
Ultrasonic Cleaning
Use of an ultrasonic bath and solvent should work on loose particulate and some organic matter.