Talk:Atomic force microscope

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[edit] TAG

I think this article should be tagged for review by an expert , it seems to be a bit incoherent. Akashag27 (talk) 16:58, 7 April 2008 (UTC) 
I agree, it needs lots of editing, the references should be numerical, shouldn't they?--Jpeaton (talk) 15:19, 9 May 2008 (UTC)

[edit] Detection Method

I think most AFM's (I know of, anyway) use the laser reflection detection method. Feel free to put back the interferometry if I'm wrong.

RE: Added some other possible detection methods. Although laser reflection is most common, things like interferometry, piezo-levers etc. are used as well in some (and growing) applications -- PMH, July 7, 2006

The original AFM as built by Binnig &co had an STM on the back to detect lever deflection. I think a few groups now are developing MEMS based levers for more accurate detection of deflection (although I can see this approach creating new problems the optical lever approach doesn't have). DJ

[edit] Tapping Mode

Also, I think tapping mode is a trademark of DI/Veeco, but I'm not sure if it's "tapping mode" in general or "TappingMode" which they've got on their website - if someone is better informed, fill me in. --Bibble 13:58, 27 Jul 2004 (UTC)

RE: Tapping mode is not a registered trademark anymore(search for TappingMode on www.uspto.gov), however the Tapping patent by DI/Veeco is still maintained.

RE: Perhaps adding more information about phase imaging and how it can detect different materials on the surface.

RE: In my opinion, there should be a section on Non-contact AFM(NCAFM), which would include tapping mode as well. -- RK, October 20, 2007.

Re: This is easy enough to get around by renaming the section Intermittent Contact mode. -elypse Nov. 28 2007

[edit] Force

Perhaps this article should include what force is being measured? For an AFM its the van der waals interactions between the tip and the sample, but the article doesn't indictate this. 24.59.193.0 02:19, 26 September 2005 (UTC)

The article claims Casimir forces are also used in AFM. This looks like impossible, Casimir forces are too little to be measured between plates the size of a door. Could somebody double-check this?
Definately literature on this. Don't have a reference to hand though...82.5.50.61 22:39, 6 July 2007 (UTC)
Umar Mohideen at University of California Riverside has done substantial work on measuring the Casimir Force. I attened a talk he gave at Harvey Mudd College in which he discussed his use of an AFM to measure the Casimir Force. The setup is rather novel: an atomicly flat conductive substrate such as gold, a probe with a polystyrene sphere attached to the end, an AFM, and a system for ensuring the respective surfaces are electrically nuetral. I suggest searching the litereture if you are still skeptical. Keep in mind that the AFM can resolve features on the order nanometers. In other words the instrument is capable of very small movements in the z direction. —Preceding unsigned comment added by 67.180.159.152 (talk) 20:53, 26 September 2007 (UTC)

[edit] Re: Force

The AFM isn't necessarily measuring the van der Waals interactions, it simply is measuring the deflection of the cantilever, of which some force is exerted on. What this implies can vary, you can get van der Waals interactions (depending if you control your experiment correctly and apply the applicable modeling theory), among/ other things, such as friction data, capillary forces, hardness of a material, etc.

[edit] Re2: Force

Added other forces besides van-der-Waals. Agree with writer above, AFM is just measuring whatever forces are present, depending on situation. Of course, Van-der-Waals is important, as it is the one force that is always present. Maybe a discussion of different forces & related techniques would be useful or would that be too much ? -- PMH, July 7, 2006

[edit] Nanolithography and nanomanipulation

Perhaps there should be a little more info on the ability for using AFM's for manipulation, for example nanolithography, or for moving around and cutting up large molecules like DNA?

--Kiwifish 04:51, 5 January 2006 (UTC)

RE: Here's a better link, nanolithography

[edit] Force-distance measurements

It also needs discussion of force-distance curves as the second most important application after imaging. I migh get to it one of these days. -- PMH, July 7, 2006

Added a section on force-distance measurements. - Aug 22, 2006

[edit] SEM resolution

Can somebody do something about the 100 nm resolution for SEM? It seems much to low, even in the Wikipedia SEM article it says: "Depending on the instrument, the resolution can fall somewhere between less than 1 nm and 20 nm." While sub-atomic resolution is possible with the AFM (Hembacher et al. Science 305 (2004) 380-383) the normal resolution is not much different from SEM.

I deleted the sentence about SEM resolution. --Grmf 16:06, 27 July 2006 (UTC)

[edit] Veeco Images

[edit] Microscope Images

Note how all the links go directly to a www.veeco.com . The section is misleading, for an image gallery, follow proper procedures with image thumbnails and no external links