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CAFM current through signal access module

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Deepak posted on Thu, Aug 20 2015 4:43 AM

I am carrying out CAFM measurements of thin film samples using nanoscope IIIa equipped with a signal access module. We are carrying out both current mapping imaging and local I-V measurements at one position.

We want to access the current signal (during local I-V measurements) out from the signal access module. This is required for the noise measurements.

 

Is it possible to obtain CAFM current through one of the ports of the signal access module?  Kindly advice how to proceed 

 

 

Thanks in advance

 

Deepak 

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Bruker Employee
Verified by Peter De Wolf

Hi Deepak,

Thanks again for providing more detial on this application, in our direct communication. I am glad to hear things work fine now.

Also thanks for pointing out that the correct BNC is the Aux-B one, and not the AUX-D one.

Peter

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Top 25 Contributor
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Points 298
Bruker Employee

Hi Deepak,

The exact BNC on whcih you can access the 'current' output depends on the type of signal access module (SAM) you have.

1) The small SAM-AM, which provides access to all the signals which go in & out the application modules like CAFM (the app module is ocnencted to this SAM by its 15pin micro-Dsub cable). Teh OUT-DC1 BNC is the one you look for.

2) The SAM (which is larger & rectangular and can have BNCs on both the top and side surface, or only the top surface): I think you can get the 'current' signal on the AUX-D BNC connector.

Peter

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Deepak replied on Thu, Oct 15 2015 4:28 AM
Hi Peter
We carried out  CAFM based I-V measurements as suggested by you. The signal access module seems to be of the kind mentioned in point 2 of your post above

We used the AUX D channel on the SAM while the I-V spectrum of HOPG  was being acquired  and connected the AUX D channel  to the 6517 electrometer. From the I-V spectra being displayed on the computer screen we can see that the max current is around 500 nA at around 1V.
But when the AUX D channel is connected to the electrometer there is always an output current of 16 mA even when no voltage is applied. In the presence of this current even on application of voltage we do not get any change from this background value.
Deepak

 

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Top 25 Contributor
26 Posts
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Bruker Employee

Hi Deepak,

Can you please email me (peter.dewolf <at> bruker.com) tyour contact info & the details of the configuraiton you are using (controller / extender type / conductive-AFM module type / SAM type)?

When trying to display the AuxD signal on an external oscilloscope, make sure to connect to the AUXD-OUTPUT BNC, and not the INPUT one.

Peter

  • | Post Points: 10
Top 25 Contributor
26 Posts
Points 298
Bruker Employee
Verified by Peter De Wolf

Hi Deepak,

Thanks again for providing more detial on this application, in our direct communication. I am glad to hear things work fine now.

Also thanks for pointing out that the correct BNC is the Aux-B one, and not the AUX-D one.

Peter

  • | Post Points: 11
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