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Hello,
I would really appreciate it if someone could help me out with this.
I am trying to measure the hardness of thin oxide films (~1 um) deposited on metal substrates and I am having a few issues:
1. I was initially using the PDNISP-HS probe to do this, since literature shows that samples similar to ours have hardness of ~5-20 GPa and young’s modulus of ~100 GPa. I was able to get good indents, but the force curves had a loop (slide1). I am not sure why this happened. On using the 5 N/m probe (Tap150), I was able to get ‘normal’ force curves (slide2). But in order to calculate hardness, I need to measure the area of the indent made, which in this case I am not able to – the tip radius is too small, it does not leave a significant imprint on the sample. So I am still not sure what kind of probe I need to use to perform nanoindentation for hardness calculations.
2. All the plot in the Help menu of the nanoscope analysis software are Force vs. Separation curves, whereas the plot I get is TM Deflection (V) vs. Z (nm) or Z position (nm). What is the difference between Z and Z position? Also, under channel data: in the display mode the TM deflection vs. Sep is greyed out. I know that separation = Z piezo ext – cantilever deflection – const. that sets the zero deformation point. How do I calculate the cantilever deflection?
3. Either way, I am not even able to calculate the Young’s modulus using the nanoscope software. When I click on ‘indentation’ it gives me an error saying ‘Error: Indentation analysis is only available for deflections channels that have deflection sensitivity and spring constant.’ (slide3). I cannot do a calibration using thermal tune since the frequency is >50 kHz. I can however only calibrate the deflection sensitivity by executing a force curve on a hard surface (I used a Si wafer). Even after modifying force parameters I am not able to do the calculations – it still gives me the same error (slide 4).
Here is the file with the pictures: Nanoindentation.pptx
So....how do I go about hardness calculations?
-Aarthi
Hello Aarthi,
I am not 100% sure it will work with the Tm deflection, but I am pritty sure you have to fill in the tip-diameter, can not be zero. If you did not calibrate it, you can use an average value from the probe side, 40 nm. Your springconstant is around 300 N/m instead of 5 N/m. Your Poissoint ratio ... fill in 0.1 instead of 0. Your Half angle ? ~40 degrees.
Try it with this values.
Joop
Hi Joop,
Even after I put in the values for tip dia, spring constant etc, it still does not allow me to calculate the youngs modulus using the 'Nanoindentation' function. It gives me the same error: Error: Indentation analysis is only available for deflections channels that have deflection sensitivity and spring constant.
I am not even able to get the force-separation curve. After calibrating to obtain the sensitivity and the spring constant, I still get tm deflection vs. z or z positions.
Hi,
I think first of all you need to update your deflection sensitivity; After calibration you should have obtained a deflection sensitivity and also deformation sensitivity then use these values before you export your force curves from the hsdc file after this then you can use the indentation to calculate your modulus.
For Indentation calculation you need to have four parameters otherwise your calculation will be accurate:
1)Deformation sensitivity
2)Deflection sensitivity
3) Tip radius
4)Spring constant
All the best...
Mariam
Hello to everyone!
I am trying to measure the mechanical properties of a polymeric thin film and I am not able to calculate the Young's modulus with nanoscope softwere. I am doing a contact mode AFM analysis, but when I click on "indentation" analysis with nanoscope I obtain the force VS separation curve but the results of the indentation are all zero.
Could someone, kindly, help me?
Thanks for your attention,
-Marica