Real-time phase shift interference microscopy

Area of Science:

• Optical microscopy
• Metrology
• Surface science

Background:

• Accurate and high-speed 3D surface characterization is crucial for advanced manufacturing and scientific research.
• Existing microscopy techniques often face limitations in speed, accuracy, or both, hindering real-time analysis of dynamic processes.

Purpose of the Study:

• To develop and demonstrate a real-time phase shift interference microscopy system.
• To achieve high-speed (50 volumes/sec) and high-accuracy (2 nm repeatability) 3D measurements.
• To showcase the system's applicability in dynamic focusing, tilt measurement, roughness analysis, and 3D profiling.

Main Methods:

• Implementation of a polarization-based Linnik interferometer.
• Utilization of three synchronized, phase-masked, parallel detectors for real-time data acquisition.
• Development of algorithms for phase retrieval and 3D reconstruction.

Main Results:

• Demonstration of a real-time phase shift interference microscopy system operating at 50 volumes per second.
• Achieved 2 nm height repeatability, indicating high measurement accuracy.
• Successfully applied the system to dynamic focusing control, tilt measurement, submicrometer roughness measurement, and 3D profiling of fine structures.

Conclusions:

• The presented system offers a significant advancement in real-time, high-accuracy 3D metrology.
• The demonstrated capabilities open new avenues for in-situ monitoring and analysis in various scientific and industrial fields.
• This technology provides a robust platform for precise surface characterization at high speeds.