Micro Strip Line-Based On-Chip Terahertz Integrated Devices for High Sensitivity Biosensors

Abstract

We have achieved label free DNA hybridization detection at the level of a few femto-moles using on-chip terahertz (THz) integrated devices. The devices consist of two photoconductive switches for the generation and detection of THz pulses. A DNA specimen placed in a reservoir on the micro strip line (MSL) connecting the switches delays the propagating THz pulses. Different delay times were observed depending on the DNA conformation. The high sensitivity achieved is due to MSL design adjustment and the use of a specimen reservoir. Both simulations and experimental results indicate that devices with a narrower MSL have higher sensitivity.