Atomic Force Microscopy(AFM)

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VT
Posts: 314
Joined: Fri Nov 09, 2007 12:30 pm

Atomic Force Microscopy(AFM)

Postby VT » Fri Apr 25, 2008 11:51 am

How many of you guys have experience working with AFM? I am trying to 'play around' with this machine and I was wondering if any of your guys have some experience using this machine that you could share. Apparently, my Prof has not used this machine before so I am all on my own. I read the manuals and I am following all the instructions, but I am still not sure how we load a probe on the tipholder.
Also, how can we adjust the laser beam to fall right on top of the tip(probe)?

Any help will be appreciated. Thanks.

vroomfondel
Posts: 43
Joined: Thu Dec 07, 2006 9:47 pm

Re: Atomic Force Microscopy(AFM)

Postby vroomfondel » Fri Apr 25, 2008 10:16 pm

there are usually 3 or 4 laser diodes that detect the signal. your manual should have something about A+B and A-B values, there is a threshold for these values. You can keep tweaking the x-y positioning of the laser spot until you hit this threshold. you are then aligned.

are you planning on running in contact mode?

VT
Posts: 314
Joined: Fri Nov 09, 2007 12:30 pm

Re: Atomic Force Microscopy(AFM)

Postby VT » Sat Apr 26, 2008 1:48 am

Thanks vroomfondel.
Yes, I am planning on running it on contact mode.
Do you have any idea on loading a tip on to the tip holder? There are plenty of cantilevers lying on those tiny plastic boxes, but I could not figure which one to use/ how to use :oops:

Also, is there any way to get an image of the prob on the monitor( not the comp.)?
I will appreciate any help. Thanks.

vroomfondel
Posts: 43
Joined: Thu Dec 07, 2006 9:47 pm

Re: Atomic Force Microscopy(AFM)

Postby vroomfondel » Wed Apr 30, 2008 3:35 am

tips depend on how much force you want to apply (setpoint for feedback, and the spring constant of the tip), your desired resolution, substrated, and scan speed.

do you have a manual for this afm? tip loading should be described.if you don't, search online with the model number (I assume it's a commercial af). i can't tell you how because there are many different types.




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