The Nanoscale World

Search

  • Re: Colloidal probe calibration

    Correct. Yes, I understand that it might be difficult to get a good force curve in air due to the high adhesion. But you should be able to use a ramp size of up to nearly 20um, if that's what it takes to overcome the adhesion. -Ben
    Posted to SPM Digest (Forum) by Ben Ohler on Wed, Nov 28 2012
  • Re: Colloidal probe calibration

    OK, that's a definite improvement. But I will caution again that the deflection sensitivity in air varies from the deflection sensitivity in fluid. Since this enters into the spring constant calibration as squared term, any error in deflection sensitivity becomes a bigger error in spring constant. -Ben
    Posted to SPM Digest (Forum) by Ben Ohler on Wed, Nov 28 2012
  • Re: Colloidal probe calibration

    You should definitely calibrate both the deflection sensitivity and the thermal tune in the same conditions (air or liquid). The deflection sensitivity does vary somewhat from one to the other. I'm guessing that you see a huge adhesion in air and you are trying to avoid that by calibrating the deflection sensitivity in liquid. But then in liquid
    Posted to SPM Digest (Forum) by Ben Ohler on Wed, Nov 28 2012
  • Re: Signal Access Module-RS232

    Sorry, the dsub-9 connector on the signal access module does not provide digital access to the data and control signals. On our older controller architecture there was a provision for basic serial communication through the main 37-pin connector interface. These lines (just TXD, RXD and ground) were broken out and connected to a dsub-9 connector on the
    Posted to SPM Digest (Forum) by Ben Ohler on Wed, Oct 24 2012
  • Re: Tipless probes calibration

    Sure, this is possible. The only real issue is that the high adhesion between a tipless cantilever and a clean, hard surface can make it difficult to measure a good force curve for deflection sensitivity calibration. I addressed this issue in air for some work I published several years back (B. Ohler, Rev. Sci. Instrum. 78, 063701, 2007). I used the
    Posted to SPM Digest (Forum) by Ben Ohler on Wed, Oct 10 2012
  • Re: Calibration Standards: electrical

    Thanks Andres Here's a link to the specific page with more information: http://www2.imec.be/be_en/collaboration/services/cams/calibration-and-resolution-qualifi.html -Ben
    Posted to SPM Digest (Forum) by Ben Ohler on Thu, Aug 16 2012
  • Re: Crop results in different height scale

    Thanks for reporting this bug. We've investigated it and found the problem. We'll be releasing a new version with the fix soon. Until then, there's a simple workaround. After you flatten the image, be sure to save it before using crop and split. You can either save over the original file or save under a new filename. Then reload the saved
    Posted to SPM Digest (Forum) by Ben Ohler on Tue, Aug 14 2012
  • Re: Regarding Thermal tune to determine Spring k of cantilever and other questions

    Current measurements are not generally done under liquids with AFM. Normally the leakage current through the liquid is too large (i.e. larger than the current you're trying to measure). There are groups in the world working to develop insulated AFM probes where only the very apex is exposed that might enable these kinds of measurements. You can
    Posted to SPM Digest (Forum) by Ben Ohler on Mon, Jul 30 2012
  • Re: what is cut-off frequency for 500khz HSDC?

    Fei, The general IO outputs (via the front panel) are bandwidth limited because the signals get sampled and then written back out. This is a different signal path from HSDC. If you sample deflection directly from HSDC (selecting it as a data type) then it has the bandwidth that Bede describes. -Ben
    Posted to SPM Digest (Forum) by Ben Ohler on Wed, Jul 25 2012
  • Re: thermal tune for cantilever stiffness disagree /questions on 'practical advice on the determination of cantilever spring constants'

    Fei, The first thing to check is that the data scaling is correct. I would recommend collecting a normal force curve with HSDC and compute the deflection sensitivity yourself using the same data path and file import method that you're using for the thermal tune data. Any errors there will have a big effect. The other thing to check is your calculation
    Posted to SPM Digest (Forum) by Ben Ohler on Wed, Jul 25 2012
Page 2 of 7 (69 items) < Previous 1 2 3 4 5 Next > ... Last » | More Search Options
Copyright (c) 2011 Bruker Instruments