Imec has unveiled a groundbreaking color rendering technology at IEEE IEDM 2023, designed to fundamentally revolutionize camera performance by overcoming the limitations of traditional CMOS imagers. The innovation utilizes an array of vertical Si3N4 multimode waveguides, constructed using standard 300mm back-end-of-line processing, to faithfully split colors with sub-micron resolution. This method collects over 90% of incident photons (within the human color perception range), effectively going "beyond the fundamental Abbe diffraction limit" by spatially separating colors based on the unique "beating" patterns of propagating light modes. The technology promises higher signal-to-noise ratio, enhanced color quality, unprecedented spatial resolution, and cost-efficient production, positioning it as a potential future standard for diffraction-limited color imaging in applications ranging from smartphones and automotive to medical devices.
Imec's Breakthrough in Sub-Micron Color Imaging
N/A – Introduction of Novel Technology: Imec presented a fundamentally new method at IEEE IEDM 2023 for rendering colors with sub-micron pixel sizes, promising to revolutionize camera performance.
N/A – Addressing Current Limitations: Traditional CMOS image sensors, limited by color filters (like Bayer matrix), struggle to balance photon collection, resolution (down to diffraction limit), and accurate color recording. Smaller pixels capture less light and suffer from interpolation artifacts.
N/A – Imec's Waveguide-Based Solution: The new approach uses an array of vertical Si3N4 multimode waveguides in an SiO2 matrix, compatible with standard back-end-of-line processing on 300mm wafers.
N/A – How Color Splitting Works: Each waveguide has a tapered, diffraction-limited input (e.g., 800x800 nm²) to collect light. Incident photons excite symmetric and asymmetric modes that propagate differently, creating a unique "beating" pattern that results in spatial separation of colors at the waveguide's output.
N/A – Superior Light Collection and Quality: This technique is estimated to collect over 90% of total output light within the human color perception range (400-700nm), outperforming traditional color filters which can absorb up to 70% of light. It delivers higher signal-to-noise ratio and enhanced color quality with a Vora value > 95%.
N/A – Manufacturing and Scalability: The technology is compatible with standard 300mm processing, enabling cost-efficient production and further scaling of high-resolution imagers with sub-micron pixel sizes.
N/A – Ambitious Future Vision: Imec aims for this technology to become the future standard for color imaging with diffraction-limited resolution, with the ultimate goal of detecting every incident photon and its properties.
N/A – Broad Market Applications: This innovation is highly relevant for numerous markets including high-end cameras, smartphones, automotive, and medical (e.g., endoscopy).
N/A – Call for Industry Collaboration: Imec is actively seeking industry partners to collaborate on achieving a full camera demonstration of this promising technology.