Composite microstructures for optical data storage

We design and fabricate polarization-dependent components (PDCs) based on all-dielectric, fully planarized, multilayer microstructures of 150 nm period by using low-loss materials. Quarter-wave and half-wave phase plates at 405 nm are presented. Wafer-level retardation within +/-7deg of the targets and wavefront distortion at 10mm-aperture <20mλ rms are achieved. We also discussed the reliability of various composite microstructures. Stress-test up to 2000 hours at 85°C and 85% relative humidity confirmed that even air-channeled microstructures surpass very stringent reliability requirements. Multifunction integrated diffractive PDCs are discussed.