SBIR Phase I:NM/N5: A fast, wide-field nano-precision metrology microscope using a time-multiplexed and multi-frequency synchronous detection

This Small Business Innovation Research Phase I project will establish the feasibility of transforming a wide-field optical microscope into a real-time imaging/metrology system. The system will have a spatial resolution better than 10 nanometers, when used as a wide-field optical microscope, and better than 1 Angstrom when used as a position tracker for nanoscale particles. Recent progress reaching effective resolutions below the Rayleigh diffraction limit of ~200 nm has spurred research in the fields of medical imaging and micro metrology. However, these optical microscopes and interferometers rely on a temporal image formed on an image sensor for the intensity and phase map calculation, which makes it difficult to isolate the measurement from vibration and other noise. In order to mitigate this issue, we will develop a system which integrates (1) an active optoelectronic mixing method to provide fast, synchronous phase-amplitude detection within a single frame acquisition time with high signal-to-noise and dynamic range, (2) a picometer-resolution motion scanner for precise active positioning of the pixel and/or structured illumination pattern with real-time super-resolution image reconstruction and (3) a real-time signal processing engine to solve the complicated inverse filter problem, to allow fast processing and better image resolution. The broader impact/commercial potential of this project is to provide an economical add-on solution to optical microscopes to enhance observation and metrology performance to a level which is comparable to much more expensive electron microscopy or scanning probe systems. The resulting add-on system will allow many researchers and industrial users to significantly enhance their existing optical microscopes' performance at a fraction of the cost of conventional high-resolution imaging systems. The proposed system is expected to increase imaging productivity for manufacturing process evaluation and quality inspection in the fields of biomedical science, semiconductor devices, data storage and optical components. The new imaging capability, integrated with a quantitative phase measurement capability, is not only useful for life science (for example, for understanding system behavior at the molecular level in living cells), but also vital for inspecting and measuring surface parameters and nanoscale particle behavior for semiconductor manufacturers, makers of high precision optical components, and others involved in the fabrication and inspection of nanoscale materials and systems.