Nanoindentation

Nanoindentation

Nanoindentation – or “instrumented indentation” testing – is a quasi-static mode of nanomechanical analysis used to measure force response properties of very small, solid samples. Predominantly, this technique is used to measure the hardness and scratch resistance of sub-micron-scale regions of materials.

To make a nano-indent measurement, an indenter tip (made of a material necessarily much harder than the sample; commonly: diamond) is pressed into the sample surface with unknown mechanical response. A force is applied to the tip and is increased until it penetrates the surface to a user-defined stopping point, after which the force is stopped or sustained for a preset duration of time. The area and depth of the indentation in the sample are measured, typically using high-performance optical microscopy. These provide a metric for hardness, and can be used to interpolate Poisson’s Ratio, the Young’s Modulus, and Strain properties of the sample.

Nanoindentation is distinct from nano-scratch testing, in that it involves no lateral displacement.

Application Areas for Nanoindentation

Nanoindentation is a quick, straightforward way to access many mechanical properties of a material. It is widely used in thin-film industries, including semiconductors, electronics, packaging, coatings, depositions, thermal and electrical insulation, polymer chemistry, and metallurgy.

Measurements from Nanoindentation

  • Stiffness
  • Hardness
  • Modulus
  • Deformation under Strain

USES & LIMITATIONS FOR Nanoindentation

  • What it is great for:
    • Mechanical analysis of thin-films and other nano-scale solids
    • Hardness test for films > 50 nm
    • Efficient data collection
    • Minimal sample preparation
  • Limitations:
    • Destructive
    • Works best for linear, isotropic samples
    • Soft materials and adhesives introduce measurement error

EXAMPLE OUTPUTS

Force v. Displacement Curve for fused quartz sample, demonstrating the standard response of an elastic/plastic material. Below, the corresponding image of the nano-indent impression in the quartz.
From Bruker.

INSTRUMENTS we use for Nanoindentation

Bruker Hysitron TI Premier High- and Low-Force

These best-in-class nanomechanical testing tools provide customizable, high-accuracy, efficient measurements of a variety of nanoscale mechanical and tribological properties. A suite of customized modules facilitates analysis using quasi-static, dynamic, high-temperature and spatial mapping detection modes. With an ultra-precise, built in optical microscopy system and unique capacitative transducer technology, the TI Premier is the industry leader in nanomechanical testing technologies.