AFM: Question about building one

[Son of Ole]

Hey all. I'm not sure of the best forum to post this in, so I am putting it here.

I was wondering if anyone knows anything about or any resources for building a "homemade" AFM?

It wouldn't need to be state-of-the-art or even all that good. Just good enough to show undergrads how they work and do some basic surface scans.

What kind of time and resources would it take? Anybody done this on this forum?

Thanks

 

[Danger]

Believe it or not, I think that I remember seeing something about this somewhere. Can't for the life of me remember where or when. If it comes to mind, I'll let you know. (Maybe snoop through back-issues of Scientific American.)

 

[Claude Bile]

The simplest way would probably be using a cantilever sensor (normal-force sensor), as shear-force sensors require complex electronics.

Typically you measure the flexure of a cantilever using a laser bounced off the cantilever arm. You would also need a micropositioner of some sort to position the cantilever correctly (nothing too fancy though). On top of this you will need a computer and the appropriate software, such as Labview to record the data. You may also want something with a precisely known morphology (topology) to test and calibrate the device such as a phase mask or a diffraction grating.

How long will it take time wise? Well that depends on the degree of assembly of the cantilever sensor system. You can buy 'plug and play' type systems for Academic purposes, but they are expensive. If you need to mount everything yourself, it may take a little longer. It will also depend on whether Labview software is readily available and to what degree you will need to modify existing VIs (and how competent you are with Labview too I guess).

I would guess maybe a couple of weeks to a month of solid playing around to get the device working, maybe a bit less if the instrument is particularly robust (I have never built one of these myself, so I'm not sure how sensitive the engineering requirements are, how affected it will be from vibrations for example).

If I come across any resources for this type of instrument, I'll be sure to post them.

Claude.

 

[Son of Ole]

Further info?

Thanks for your replies Claude and Danger.

Anyone else know of any specific resources?

I am considering doing it for my senior thesis, but would like to know the full range of problems I would run into. I would have three months of about 20-30 hours a week to devote to it, give or take.

Thanks

 

[Claude Bile]

Here are a few companies that sell AFMs, most have websites that have a bit of info about AFM and usually a few links.

Veeco - http://www.veeco.com/
NT-MDT - http://www.ntmdt.ru/
Nanonics - http://www.nanonics.co.il/index.php?goto=bep

Google-ing AFM yielded the following as well

http://stm2.nrl.navy.mil/how-afm/how-afm.html
http://www.chembio.uoguelph.ca/educmat/chm729/afm/firstpag.htm
http://en.wikipedia.org/wiki/Atomic_force_microscope
http://spm.phy.bris.ac.uk/techniques/AFM/

Hopefully that should get you started. There is also a ton of papers on AFM in various research journals - Ultramicroscopy and Review of Scientific Instruments tend to be the best when it comes to technical stuff.

Claude.