Sputter Deposited Zinc Oxide Photoconductive Antenna on Silicon Substrate for Sub-Terahertz Time-Domain Spectroscopy

Abstract

In this paper, we report on the design, fabrication and characterization of a zinc oxide (ZnO) photoconductive antenna as a sub-terahertz (THz) pulse emitter or detector for time-domain spectroscopy (TDS). A ZnO thin film is deposited by rf magnetron sputtering on a silicon substrate. The resistivity of the deposited ZnO was 9.6×10⁴Ω·cm. The fabricated ZnO photoconductive antennas are evaluated using a TDS measurement system. Photoconductivity of ZnO is obtained using a Ti:Sapphire femto second laser with a wavelength of 775 nm. The bandwidth of the ZnO photoconductive antenna is evaluated to be 1 THz.