Nanomechanical Characterization of Vertical Nanopillars Using an MEMS-SPM Nano-Bending Testing Platform

Area of Science:

• Materials Science and Engineering
• Nanotechnology
• Mechanical Engineering

Background:

• Nanomechanical characterization of micro- and nanopillars is vital for the quality control of pillar-based sensors and devices.
• Existing methods may lack the precision or capability for high-aspect-ratio nanostructures.

Purpose of the Study:

• To develop a microelectromechanical system based scanning probe microscope (MEMS-SPM) for quantitative measurement of bending stiffness.
• To enable high-resolution, in-plane nanomechanical characterization of micro- and nanopillars with high aspect ratios.

Main Methods:

• Development of a MEMS-SPM with large in-plane displacement, subnanometric resolution, and a probing force exceeding 100 micro-Newtons.
• Implementation of a proof-of-principle experimental setup to measure the in-plane bending stiffness of silicon nanopillars (aspect ratio > 10).
• Comparison of experimental results with analytical and finite element method (FEM) evaluations.

Main Results:

• Successful experimental determination of the in-plane bending stiffness of silicon nanopillars.
• Demonstrated agreement between experimental data and analytical/FEM models.
• Achieved measurement uncertainty better than 5% for pillar bending stiffness when it is close to the MEMS-SPM's suspending stiffness.

Conclusions:

• The developed MEMS-SPM system provides a reliable method for quantitative nanomechanical characterization of pillar-like nano-objects.
• This technique is applicable to various materials and facilitates on-chip characterization.
• The system enhances quality control for micro- and nanodevices relying on pillar structures.