Raman Spectroscopy and Nanoindentation: Combined Analysis and Applications

Combining Raman spectroscopy and nanoindentation enables correlated chemical and mechanical analysis of materials at the micro- and nanoscale. This approach allows researchers to understand not only the material composition but also how structure influences mechanical behaviour, such as hardness, modulus, and wear.

This page explains how Raman spectroscopy and nanoindentation can be combined, typical applications, and example use cases in materials research.

What is correlative Raman and nanoindentation analysis?

Correlative analysis combines multiple techniques to provide complementary information about a material. Raman spectroscopy provides chemical and structural insights, while nanoindentation measures mechanical properties such as hardness and modulus.

By combining these techniques, researchers can directly link chemical composition to mechanical performance.

Raman Spectroscopy and Nanoindentation Overview

Raman spectroscopy is a powerful analytical technique for studying materials, providing information about composition, uniformity, stress, strain and disorder. However, Raman cannot directly characterise physical, mechanical, or tribological properties.

By combining Raman spectroscopy with nanoindentation, you can correlate mechanical and tribological properties with chemical information, including crystallinity, polymorphism, phase, stress and strain:

• Nanoscale indentation, scratch and wear
• Mechanical and tribological properties
• Surface topography imaging with in-situ SPM
• Chemical and structural properties

How Raman Spectroscopy and Nanoindentation Are Combined

The Renishaw inVia™ confocal Raman microscope can be combined with the Hysitron TI 950 TriboIndenter, enabling you to correlate mechanical properties with full chemical analysis in situ.

The two systems are coupled using fibre-optic technology to form a perfectly combined system and are firmly mounted on a granite bridge.

This means you can measure the same location on your sample with indentation and Raman spectroscopy without having to transfer the sample between instruments and relocate your region of interest. You can acquire:

• Optical white light images
• SPM images
• Raman point spectra
• Raman images
• Nano- and micro-indentation data

Both the inVia™ and the nanoindenter can be used independently or simultaneously as needed, without compromising the performance of either system.

Using both analytical techniques, the correlated data provide greater insight into your material’s mechanical properties and deformation behaviour at the nanoscale and microscale.

Diamond-Like Carbon (DLC) Analysis

Diamond-like carbon (DLC) is a metastable amorphous material. The wear resistance, very low coefficient of friction, hardness, and elastic modulus of DLC films can be comparable to those of diamond. Its mechanical, chemical, tribological, optical and electrical properties depend on the abundance of sp³ and sp² bonds in the structure.

Complementary mechanical and chemical data from indentation and Raman can provide a better understanding of the material.

In this example, three DLC films were deposited on silicon wafers using different deposition techniques. Raman point spectra were taken, and indentation curves were then measured to determine the hardness and modulus. The indentation curves of the three coatings correlate with the variations in their Raman spectra.

Sample C (black) is the thinnest film at 40 nm. It is also the softest, so the indentation is affected by both the softer silicon substrate and the harder DLC film. This causes the ‘elbow’ in the unloading section of the curve. The thinness is also indicated by the silicon signal in the Raman spectrum from the substrate, showing that light can penetrate the thin coating.

Correlative Wear Testing

Sample C was then further tested using a wear measurement with a Berkovich indenter. It was moved across the sample five times at 1 Hz with a 500 μN normal force to create a wear pit. The optical, SPM (Scanning Probe Microscopy), and Raman images are shown below. Raman spectra were also acquired from inside the pit, the edge, and the unaffected surface.

The lighter section in the middle of the optical image, and the height change revealed by SPM, indicate that the film has been worn away at the bottom of the pit, exposing the silicon substrate. The Raman spectrum confirms this by showing the presence of silicon instead of carbon.

You can see debris at the edges of the pit and an increase in height in the SPM image. The Raman spectra from the edge of the pit and the plain surface show an additional peak attributed to debris and disordered carbon. This indicates that the process moved coating material to the edge of the wear pit, and the deformation transformed the structure from predominantly sp³ to defective graphitic sp².

Further information about these tests is available in a Renishaw application note.

Applications of Combined Raman and Nanoindentation Analysis

This combined approach is used across a range of applications, including:

• Thin films and coatings
• Tribology and wear analysis
• Semiconductor and microelectronics materials
• Polymers and composites
• Advanced materials research

Products

Systems such as the Renishaw inVia™ Raman microscope and the Bruker Hysitron TI 950 TriboIndenter enable fully integrated correlative analysis workflows.

Blue Scientific is the official Nordic distributor for Renishaw Raman and Bruker Nano Surface Analysis systems in Sweden, Norway, Denmark, Finland and Iceland. For more information or quotes, please get in touch.

Last updated: March 2026