Seemic officially launches AROSS-S100, an optical critical dimension metrology equipment based on angle-resolved scattering. It targets non-contact optical measurement of films, gratings, nanowires and periodic microstructures, and is the first product of the OCD metrology line.
Measurement principle
The instrument collects reflection and scattering signals across wavelengths, incidence angles and polarization states, relates the optical response to structural parameters, and — combined with RCWA electromagnetic modeling and numerical fitting — inverts the critical dimensions and optical properties of the sample.
Using model-inversion based non-imaging measurement, the system does not rely on directly imaging the microstructure and can characterize structural parameters below the resolution limit of conventional optical imaging. For films it analyzes film and multi-layer film thickness; for gratings and periodic structures it inverts pitch, linewidth and structural height online.
Key specifications
- Selectable monochromatic light from 400 to 700 nm
- Angular resolution within 0.17°, incidence from -64° to +64°
- Probe spot 1 to 3 μm, X / Y / Z adjustable
- Any polarization angle, customizable automatic scan stage
The instrument measures fast, non-contact and without damage, and ships with self-developed fitting algorithms that keep memory footprint low and real-time computation modest, reducing the processing resources needed for complex inversions.