Wafer-scale 2.5D optics in the visible and near infrared for advanced light management

The coming of age of AR, VR and MR applications and usage scenarios relies on the development of ever-improved advanced light management systems, both for sensing (camera) and actuation (display), e.g., solid-state dToF or FMCW scanning or flash LiDAR, polarimetric imaging or resettable structured light illumination for 3D mapping, directional imager for light field registration, plasmonic or dielectric color filters and directors for efficient spectroscopic information acquisition. Indeed, optics remains the dominant user interface modality while large portions of required information can be retrieved in optical domain. These systems rely on the emergence of mature mass-manufacturing integrated photonics platforms in near infrared and visible wavelength ranges. This presentation introduces developments at imec of diffractive components for reflective, transmissive and guided applications on opaque (Si/CMOS) and transparent (quartz) substrates, relying on sub-wavelength nano-patterning techniques (from DUV dry and wet (immersion) lithography through 200mm wafer-scale e-beam, nano-imprint lithography, block-co-polymer to EUV), novel CMOS-compatible material toolbox beyond Si and SiN (passive, active, resettable and tunable) and high-aspect ratio re-filling to enable stacking of optical features to define complex functional system. In particular, we will report on pixel-integrated Fresnel phase plates for local eQE optimization, on process complexity trade-off enabled by optical meta-materials, aspherical and non-cylindrical optical components for directed light, tunable structured light scanners, plasmonic and dielectric-based color filters and directors, optical beamformer in near infrared, sub-wavelength spatial light modulator in the visible and finally novel developments for 2D optical waveguides.