LAUSR

Terahertz radiation is in spectral region of 0.1THz to 10THz between microwave and infrared part of the electromagnetic spectrum. Terahertz radiation can propagate through wide range of dielectric materials [1]. This sparked many researchers’ interest to further explore the potentiality of characterization, detection and sensing studies at terahertz range. Recently, Terahertz Time-Domain Spectroscopy has emerged as an attractive technique that enables the label-free detection on chemical and biological compounds [2]. It is because, the most of non-conductive materials such as chemical and biological compounds have unique molecular resonance that able to translate as transmission or absorption peak at terahertz range. Past studies show that, terahertz spectroscopy is more suitable in sensing, detection and characterization of various forms of material state, such as illicit drugs and explosive substances, alcohol and antibiotics contents, fructose Abstract: This paper discusses on the analysis of band pass Frequency Selective Surfaces (FSS) for performance enhancement in material sensing application. Terahertz Spectroscopy has proved to be versatile tool for detection and sensing in measuring non-conductive materials. It is because most of the non-conductive materials have unique molecular resonance that may translate as transmission and absorption of signals within terahertz range. However, the most critical issue in detection and sensing is to improve its sensitivity therefore an extremely low concentration material still can be able to be detected in THz band. Hence, in this paper, a circular slot is modeled on a planar structure of Rogers Duroid 5880LZ substrate with thickness of 508μm using Computer Simulation Technology (CST). The simulation generates a band pass response with transmission magnitude of 0.95 at 0.66THz. Furthermore, photoplotter and wet etching fabrication process is used for the realization of terahertz FSS. Simulated and measured transmission shows a good agreement between 0.5THz to 0.7THz as only 1% shifts in frequency between simulated and measured results. Besides that, the fabrication of circular FSS shows narrower measured bandwidth as compared to its simulated counterpart. Hence, with the limitation of the wet etching to produce micron size structure both simulation and measured result shows good agreement for all the critical issues in this study.