On-machine separation and compensation of target mirror's surface shape errors in multidimensional interferometric...

Area of Science:

• Metrology
• Nanotechnology
• Optical Engineering

Background:

• Interference measurement is crucial for multi-dimensional nanopositioning and nanomeasuring devices.
• Target mirrors are used as spatial reference planes, but their surface errors limit measurement accuracy.
• Existing methods struggle to isolate target mirror errors from workpiece dimensions.

Purpose of the Study:

• To develop a method for on-machine separation and compensation of target mirror surface shape errors.
• To enhance the overall measurement accuracy of multi-dimensional interference systems.
• To provide a reliable compensation model for practical applications.

Main Methods:

• Utilizing a micro-nano-coordinate measuring machine (MNCMM) with interference measurement.
• Employing a home-made resonant probe and a reference flat crystal for error separation.
• Implementing an interpolation algorithm for spatial error compensation based on a derived model.

Main Results:

• Successfully separated and compensated for target mirror surface shape errors.
• Reduced the flatness measurement error of a standard flat crystal from 175 nm to 77 nm.
• Demonstrated the reliability and effectiveness of the proposed on-machine compensation method.

Conclusions:

• The developed method effectively compensates for target mirror surface errors in interference measurement systems.
• This approach significantly enhances the precision of multi-dimensional metrology.
• The technique is broadly applicable to various on-machine compensation scenarios in nanomeasuring devices.