The method of nanoindentation is widely used to determine mechanical material properties such as hardness and Young’s modulus of materials.
It can be used for thin films of less than 1 µm thickness to determine these values without the influence of the substrate material. During the measurement, a diamond tip of known shape is pressed into the sample with increasing force, with the tip displacement being continuously measured in parallel. From the resulting load-displacement-curve hardness and Young’s modulus can be calculated.
The Keysight G200 commercial nanoindenter located at KAI includes:
- A heating option for temperature dependent measurements up to 500 °C in inert/active gas atmosphere.
- A continuous stiffness measurement option for depth dependent material property measurement.
- Express test parameter mapping for fast acquisition of material property maps.
- Keysight NanoVision nanomechanical microscopy for specimen surface and indentation imprint imaging.
Besides standard nanoindentation measurements, methods to quantitatively measure coating adhesion, which have been developed in cooperation with academic partners, are in use at KAI.
The KAI wafer curvature measurement system is a custom designed apparatus to investigate thermo-mechanical behavior of thin films on a substrate by measuring the wafer curvature as a function of temperature. It consists of an optical module, measuring curvature via an array of laser beams, a high resolution scanning stage, a rapid thermal processing chamber and several additional gas control modules.
The real-time development of biaxial stress involved in thin films can be fully captured during any thermal treatments such as temperature cycles or annealing processes. Other advanced features such as the in-situ active cooling (down to -55 °C) and active heating (up to 600 °C) with controllable heating rates extend the experimental conditions to provide new insights into thin film properties and behaviors.
From the measured stress-temperature data, material models for finite-element-modeling can be obtained and insights into the effect of temperature treatments on thin films can be gained.