[Spm] lateral signal fluctuation

[Vishal Gupta]

We have PicoScan 5.3.3 from Molecular Imaging Inc. Recently, I am seeing some problem
may be with electronics, I am not sure though. I am trying to image
microscope glass slide with Silicon-Nitride cantilever (0.12 N/m or
0.06 N/m) in contact mode in air. The vertical signal appear pretty
stable in laser electronic box during imaging but the later signal
(LFM) keeps fluctuating quite a lot. I am also seeing the fluctuation
in deflection signal monitor screen on the software and the PicoTrec
electronic controller. All these fluctuation is creating noise on the
image and change the z-range. So, when I do the roughness analysis it
show me 200 nm (RMS) which should be 1-2 nm for flat glass surface. I
also image standard silicon grating and there I see stable signal and
good quality with feature size as known. I am confused how to solve
this problem. 
 
Any suggestions or comments are greatly appreciated. 

Vishal Gupta  
216 University Village
Salt Lake City, UT - 84108
  USA  
  Ph. No. (801)585-1538 (O)          
            (801)450-2423 (M)


      
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