Micro-Fabricated THz Antenna for Short-Range Wireless Communication

In the rapidly evolving field of terahertz (THz) communications, the design and fabrication of efficient antennas pose significant challenges due to the inherent complexities of operating at such high frequencies. This paper presents a microfabricated THz antenna array featuring triangular-slot patches designed to enhance bandwidth, gain, and efficiency at THz frequencies from 0.70 to 0.95 THz. The design involves utilizing a coplanar waveguide (CPW) feed technique to simplify the microfabrication process, improving antenna integration by enhancing impedance matching and reducing transmission losses. To optimize the antenna geometry, a machine learning (ML)–assisted global optimization method, specifically the surrogate-assisted differential evolution algorithm, is used to improve bandwidth, gain, and tolerance to fabrication variations. The prototype is fabricated on a flexible polyimide substrate using electron beam lithography, with a titanium/gold (Ti/Au) metallization stack of 10/350 nm. The proposed design achieves a simulated impedance bandwidth of 37.5% (from 0.70 to 0.95 THz), a simulated radiation efficiency of 85%, and a simulated gain of 8.71 dBi, making it a potential candidate for short-range wireless communication applications. Owing to the unavailability of in-house measurement facilities at THz frequencies, the experimental validation could not be performed at this stage; however, the design process is supported by full-wave electromagnetic simulation along with an extensive optimization of every parameter using ML-enabled optimization, which are established as reliable and effective methods for antenna design and performance prediction. These results highlight its potential for compact, high data rate short-range THz systems.