Nanoplasmonic antennas are the one of the major elements in the recognition of upcoming nanoscale wireless communication systems. In this paper, the design and analysis of two multiband antennas operating at optical bands O and L bands, using metal-insulator-metal (MIM) slot waveguide based step impedance resonators (SIRs) and coplanar waveguide (CPW) fed line has been investigated. The simulation results of the two antennas (A) and (B) are obtained by using full wave simulation software (CST Microwave Studio Suite) with the return loss −20 dB and −30.79 dB at desired optical bands. The antenna (A) has a gain of 8 dBi and 7.48 dBi at 1275 nm and 1616 nm wavelengths, similarly antenna (B) has a gain of 8.46 dBi and 6.23 dBi at 1294 nm and 1613 nm wavelengths. The radiation pattern of the simulated results shows the omnidirectional pattern at desired wavelengths, which is very useful for nanoscale wireless communication systems.

A wide bandgap, an enhanced piezoelectric coefficient, and low dielectric permittivity are some of the outstanding properties that have made ScxAl1−xN a promising material in numerous MEMS and optoelectronics applications. One of the substantial challenges of fabricating ScxAl1−xN devices is its difficulty in etching, specifically with higher scandium concentration. In this work, we have developed an experimental approach with high temperature annealing followed by a wet etching process using tetramethyl ammonium hydroxide (TMAH), which maintains etching uniformity across various Sc compositions. The experimental results of etching approximately 730 nm of ScxAl1−xN (x = 0.125, 0.20, 0.40) thin films show that the etch rate decreases with increasing scandium content. Nevertheless, sidewall verticality of 85°~90° (±0.2°) was maintained for all Sc compositions. Based on these experimental outcomes, it is anticipated that this etching procedure will be advantageous in the fabrication of acoustic, photonic, and piezoelectric devices.

In this work, Lamb Wave Resonators (LWRs) based on 2 μm thin Y-cut LiNbO3 films have been fabricated using integrated fabrication process that defines IDTs (Inter Digital Transducers) on top surface and a partial Si cavity for a sacrificial layer on the bottom surface. We discuss the etch quality and its effects on the device's performance. For the first time, we present an optimized high-quality etched MEMS (Micro-electromechanical Systems) Resonator with smooth and vertical sidewalls on this material system, reporting the maximum Q-factor of 2500 at 846 MHz frequency. We observed that the resonator system has a Q-factor of 480 over the same frequency range when the etched surface has significant roughness and non-verticality. Q values of the device are greatly diminished by the presence of surface roughness and non-verticality of the etched edges. This truly highlights how important it is to have a high-quality etch profile for a piezoelectric material system like this so that the designed resonators can perform at their best.

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