Optical waveguides on three material platforms of silicon-on-insulator (SOI), amorphous silicon (a-Si:H) and silicon nitride are analyzed for realization of an optical compact link compatible with CMOS technology. The three material properties are presented. The optical components on the three potential material platforms are put together for a comparison, in which, straight, bent waveguides, and multimode-interference beam splitters for an optical link are designed, fabricated, and measured. The comparison results of simulation and measurement show that a-Si:H has a similar performances with SOI material but lower cost and good feasibility of photonic integration on silicon.

Diffractive optical elements (DOEs) are specialized optical components that manipulate light through diffraction for various applications, including holography, spectroscopy, augmented reality (AR) and virtual reality (VR), and light detection and ranging (LiDAR). The performance of DOEs is highly determined by fabricated materials and fabrication methods, in addition to the numerical simulation design. This paper presents a microfabrication technique optimized for DOEs, enabling precise control of critical parameters, such as refractive index (RI) and thickness. Using photolithography, we fabricated high-precision photoresist patterns on silicon and sapphire substrates, with 3 × 3 and 3 × 5 DOE beam splitter as examples. The results show a strong match between simulation and experimental data, with discrepancies of just 0.53% and 0.57% for DOE on silicon and sapphire substrates, respectively. This approach offers potential for advancing high-performance DOE devices in semiconductor manufacturing, supporting next-generation optical systems.

For the dimensional measurement and characterization of microsized and nanosized components, a three-dimensional microdisplacement sensing system was developed using the piezoresistive effect in silicon. The sensor was fabricated using microelectromechanical system bulk-silicon technology, and it was validated using the finite element method. A precise data acquisition circuit with an accuracy of 20 μV was designed to obtain weak voltage signals. By calibration, the sensing system was shown to have a sensitivity of 17.29 mV/μm and 4.59 mV/μm in the axial and lateral directions, respectively; the nonlinearity in these directions was 0.8% and 1.0% full scale, respectively. A full range of 4.6 μm was achieved in the axial direction. Results of a resolution test indicated that the sensing system had a resolution of 5 nm in the axial direction and 10 nm in the lateral direction.

This paper reports on an improved optical waveguide microcantilever sensor with high sensitivity. To improve the sensitivity, a buffer was introduced into the connection of the input waveguide and optical waveguide cantilever by extending the input waveguide to reduce the coupling loss of the junction. The buffer-associated optical losses were examined for different cantilever thicknesses. The optimum length of the buffer was found to be 0.97 μm for a cantilever thickness of 300 nm. With this configuration, the optical loss was reduced to about 40%, and the maximum sensitivity was more than twice that of the conventional structure.

This paper introduces a planarisation SiO ₂ layer into the configuration of ZnO‐silicon‐on‐insulator for constructing an acoustical resonant cavity to enhance the acoustic density on a silicon‐on‐insulator waveguide. The improved configuration with a planarisation SiO ₂ layer can increase the acousto‐optical interaction by about three times and 20% compared with acousto‐optical configuration of ZnO pads only in an interdigital transducer region and all over a silicon on insulator. Moreover, an introduction of a planarisation SiO ₂ layer can reduce acoustic reflection on optical waveguide and optical waveguide loss for an acousto‐optical device on silicon‐on‐insulator optical waveguides.