Dear Rj Kumar

usually you can find maney parameters with AFM:

average roughness (Ra), skewness (Rsk), and kurtosis (Rku). The average roughness is the arithmetic average of the height of the surface asperities, above a hypothetical, smooth plane . The skewness shows the degree of symmetry of

the rough surface profile and can be used as a measure of the balance between the peaks and valleys of the asperities . The kurtosis shows the degree of pointedness or bluntness of the asperities on the surface. 

If you have a software like Gwyddion you can open the AFM image and determine surface roughness using built in menu of the software.  Gwyddion is free to download and use (can be found here: http://gwyddion.net/  The site also has a decent tutorial and discusses various aspects (including statistical parameters) of surface roughness estimation.  Accuracy of roughness parameter however depends on your sampling area; remember the surface roughness estimated from AFM image is always "local" roughness.  There are other free to download software as well.  Here you will find a discussion on an array of free software: http://goo.gl/dClvMr

However, most standard software would yield only RMS roughness which may or may not be enough depending on what and how accurate data you want from your image.  It would also depend on the pixel resolution and quality of your image.  Here you will find a plethora of information on surface roughness: http://goo.gl/Wf9EgM and http://goo.gl/1DnJ53  I suggest you download and go through the literature provided in the second link -- it has been very valuable resource to us.  There are various ways to extract pixel / line scan data from AFM images that can be used to further analyze the statistical quantities.  Over last two years I have seen this topic come up for discussion in RG time and again, feel free to search RG archive as well.  

Hope this helps.

Hi, typically AFM software presents several types of Roughness in selected area: Ra, Rq, Rmax (Check the Help).   You can find an example in our recent work, where we estimated roughness of glass and polymer coatings: Journal of Micromechanics and Microengineering 09/2013; 23:105003, ·" Bonding of SU-8 to glass for gastight picoliter reactors allowing in situ optical observation "

Dear Prof., Thanks for your discuss.

I didn't have any instrument (Like Spin coating) So We are using our nano-particles samples using syringe then towards thin glass plate. I wants to know about importance of Roughness of surface on taking AFM images and  Please  tell me about evaluating journals on this concept.

Dear Prof,

I believe all of your doubts could be already answered. I just want to share a link that may help you as well to understand what the other roughness parameters existed. 

This link may not showing the details explanation but it is suffice for us to understand each kind of parameter for roughness. 

Typically, AFM itself has been built up with their own built in analysis software that you may be able to measure basic parameters like Rq, Ra, Rmax etc but then, it is up to researchers on what kind of parameter may be suited with their needs.

Some researchers are even going to analyze the PSD(Power Spectral Density) of the surface measurement profile (which in my case i am still learning about this analysis method) in order to increase their confidence level on the captured data.

p/s: please correct me if there are any uncertainties in my opinion.

Thank you.  

http://www.olympus-ims.com/en/knowledge/metrology/roughness/2d_parameter/

Dear Kanniah

Refer to the following attachment on " Measuring Surface Roughness of an Optical Thin Film With Scanning Tunneling Microscopes "

You could plot the height-height correlation function and calculate the roughness exponent from the slope of the graph.

Higher the roughness exponent, smoother the surface is.

Dear Mr.Das,

will you please elaborate more about the height height correlation function??

Miss Banerjee

I would recommend you to study the book " Evolution of Thin Films Morphology - Modelling and Simulation " by M. Pelliccione. It will help you to understand the Height-Height Correlation function.

Crudly, it explains the correlation between surface heights in the lateral i.e., x and y direction.

Ok. Thank you.