problem with cantlilever tune - Multimode AFM

Eike-Chr. Spitzner posted on Wed, Jan 9 2013 10:02 AM

rated by 0 users

Hello,

we have some problems with our Multimode AFMs.
To me, it looks like a minor issue, maybe someone of you knows what to do.

Both AFMs (1x MM AFM + Nanoscope IIIa; 1x MM AFM + Nanoscope IV) work flawlessly in contact mode. Tapping mode itself also works, but cantilever auto tune fails.
In the tuning window, the amplitude always shows a "baseline" of about 10.5 V (see screenshot below). The "real" amplitude only shows up if it reaches values larger than 10.5 V. The phase signal looks just fine and the RMS amplitude is always displayed correctly in the AFM head LCD. As a skilled AFM user you can tune the cantilever "manually", but that's neither convenient nor reliable :-)

Both AFMs worked flawlessly for years and this error appeared within 2 weeks on both instruments. So i don't really think it's a hardware issue (????)...

Somebody familiar with this????

Thanks a lot for your help

Eike-Chr. Spitzner