Forums
Bruker Media
Community Media
Bruker AFM Probes
SPM Digest
Application Notes
NanoTheater
Website
中文
Brochures & Datasheets
Publications
Probes Catalog
Events
Manuals & Documentation
Presentations
Guide to AFM Modes
News
Journal Club
Webinars & Video
Nanovations
Other
Hi everyone.
I have been previously using a SPM for a while but I have just working with a Nanoscope 3. I am using a MSNL-10 probe from Bruker. The focus of the laser on the cantilever is fine checked by paper method, but I do not manage to get a good signal on the photodiode, hence I cannot engage in contact.
I have no problem getting a good laser signal in tapping mode. Is there a trick for contact mode?
And is there a menu on the program where you can see the position of the laser spot on the photodiode (apart from the two LCDs which are on the equipment). I have spent 3 day trying to figure out the problem and to be honest I feel really bad that I cannot manage to measure in contact mode which is the simplest mode of all.
Please let me know if you have any suggestions.
Regards,
Mahkalin
Hi Mahkalin,
You probably picked a soft cantilever that is bending slightly downwards. This can be easily compensated for by moving the beam using the mirror. The adjustment of the mirror is performed using the lever on the back of the MM head. Move the lever slightly to optimize your sum signal.
Good luck,
Stefan
Thanks for your reply Stefan. However, I don't think this will solve the problem. I tried with the same tip on another Nanoscope which is the twin of our instrument and it worked. This might unfortunately mean that there is something wrong with our equipment.
Best,
Did you actually try if you can properly center the beam on the detector using the mirror?
The mirror on your other system might be adjusted slightly different and that is why you get a proper SUM signal. The mirror position is adjusted with the small lever on the back of the AFM head. It is there for that specific reason. If your system aligns a tapping cantilever fine but fails so with a much softer lever that might be slightly bend your system is most probably not broken.
Please let us know how the mirror adjustment worked out.