Dielectric properties of silicon in terahertz wave region

Abstract By using backward‐wave oscillator system, the terahertz dielectric properties of p‐type silicon were tested in the frequency range extending from 0.68 to 0.85 THz. The refractive indices, the power absorption coefficient, and the dielectric functions of various resistivity p‐type silicons were measured and compared. The variation of the refractive index of the ultra‐resistivity silicon was less than 3%, ranging from 3.037 to 3.125, but the absorption coefficient of the ultra‐resistivity silicon showed very different frequency‐dependent behaviors, ranging from 3.25 × 10 −3 cm −1 to 2.90 × 10 −5 cm −1 , within the investigated frequency range. The ultra‐resistivity silicon will be a good candidate material for terahertz transmission waveguide with ultra‐low loss. © 2008 Wiley Periodicals, Inc. Microwave Opt Technol Lett 50: 1143–1146, 2008; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.23313