The Nanoscale World

The Z-piezo voltage value keeps increasing, difference of SCANASYST-FLUID and SCANASYST-FLUID+ tips and how to get atomic resolution image in QNM?

rated by 0 users
Not Answered This post has 0 verified answers | 4 Replies | 1 Follower

Top 75 Contributor
11 Posts
Points 135
lujie posted on Wed, Jul 13 2011 12:00 PM

I'm using a Multimode 8 with Nanoscope 8.10 software and E scanner.  I got some problems when imaging some polymer deposit on silica or mica substrate in liquid with SCANASYST-FLUID+ tip. When scanning, the Z-piezo voltage value keeps increasing until eventually reaching the limit and I have to withdraw it. However after I withdraw, the vertical offset remains the same.

I check the tip catalogue and found there are two kinds of Scanasyst tip in fluid, one is sharp and the other is not. Is it because I am using the sharp one and scan on the hard surface like silica which cause the tip wear out and Z-piezo voltage increasing? How we choose these two kinds of tips based on our different samples?

The other thing is, normally we increase the scan rate to very high to get the atomic resolution image in contact mode, in QNM the scan rate seems can not over the 0.977 khz? How we get the atomic resolution image by manipulate some parameters?

  • | Post Points: 12

All Replies

replied on Wed, Jul 13 2011 1:18 PM

Hi Lujie,

It could be that your sample is swelling and hence the piezo will reach its end.

It may be a good idea to start with a regular ScanAsyst fluid tip and if you can image your sample properly then try the "+" one. The "+" ones are indeed very sharp and even though I do not think that you wear it out on the mica to explain your effect you may  effect your polymer.

In QNM the scanrate is limited by the host PC which needs time to extract the nanomechanical parameters from the datastream. This mode is not intended for atomic resolution imaging but there are plenty of examples of molecular resolution imaging. If you want to go for "atomic resolution" imaging on a lattice you may want to switch to contact mode.

Stefan

  • | Post Points: 12
Top 75 Contributor
11 Posts
Points 135
lujie replied on Wed, Jul 13 2011 1:36 PM

Hi, Stefan, 

Thanks for your reply. Is this "+" tip  suitable for harder sample like silica? Also is this sharper tip can get the high resolution compare with the normal one? That's the  only difference of these two tips?

Lujie

  • | Post Points: 12
replied on Wed, Jul 13 2011 2:58 PM

Hi Lujie,

The difference between the Fluid and Fluid+ probes is indeed the sharpness. Both are sharp compared to regular contact mode probes but the + is a bit sharper. A sharper probe may indeed provide you with higher lateral resolution and, yes, you can use it on hard samples. 

Stefan

  • | Post Points: 12
Top 75 Contributor
11 Posts
Points 135
lujie replied on Wed, Jul 13 2011 10:11 PM

Thanks, Stefan

  • | Post Points: 10
Page 1 of 1 (5 items) | RSS
Copyright (c) 2011 Bruker Instruments