The roughness and topology of a surface are so fundamental to materials that you may not realize just how far-reaching their impact is. Surface roughness is actually one of the most common physical characteristics behind product and device performance issues and it can affect a product’s yield and success across many, many applications.

To help you chart the most effective metrology solution for your surface roughness analysis, Covalent’s experts assembled an eBrief that summarizes strategies for Choosing the Right Surface Imaging Technique.

Did you know: surface roughness can impact all the following aspects of a material’s performance?






Reaction Kinetics

Specular / Diffuse Reflectance


Coupling / Resistance


Surface Area Effects

Grain Structure

Surface roughness is far from a straightforward property to measure and analyze. It is quantified using statistics, and the end result of a surface roughness measurement will vary depending on what instrument you use, what area you examine, the density of data points within that area, and the type of statistical analysis you perform. Both direct and indirect methods exist for characterizing roughness, and across the board these can be difficult to intercorrelate as raw data can lead to variable results even on comparable tools.

All of which goes to show: when you set about measuring surface roughness, it’s incredibly important that you’re selecting the appropriate technique for your sample and application. But where should you begin?

In the eBrief, I propose 2 guiding considerations you should keep top-of-mind when selecting a surface imaging / profilometry technique: required length scale and application-specific requirements.

To respond to these considerations, ask yourself these simple questions when getting started:

  • What scale is my surface roughness? (What kind of vertical resolution do I need?)
  • How big an area on the surface do I need to analyze? (What kind of lateral scan range is required?)
  • How soft is the material? How easy is it to damage? Can I damage it?
  • Is it sensitive to air?
  • Is it conductive or insulating?
  • Is it transparent or opaque?
  • Do I need qualitative or quantitative results?

Answering these questions up-front will prepare you to make the best choice when planning your surface roughness analysis. Often it also helps if you can discuss this with someone who does this type of metrology for a living.

With responses in hand, you can use Covalent’s Choosing the Right Surface Imaging Technique eBrief to narrow down your options and compare pricing, features, and strengths across 8 of the most common techniques for surface roughness characterization.

For more information about the techniques covered in the eBrief, check out: