Propagation, Resonance, and Radiation on Terahertz Optoelectronic Integrated Circuits

This paper investigates terahertz (THz) wave propagation, resonance, and radiation on a THz optoelectronic integrated circuit (THz-OEIC). An efficient THz resonant radiation from 0.6 to 0.7 THz can be achieved with a newly designed 2-D open-ended rampart slot array antenna. A monolithically integrated circuit is fabricated on a localized THz resonant cavity, which not only provides a robust base for postdevice processes but also helps collect and reradiate the fleeing surface waves to enhance radiation efficiency. When using a THz time-domain spectroscopy (THz-TDS) technique and a time-frequency analysis, the radiated THz waveform shows a good time-frequency correlation to the circuit design of our THz-OEIC. In addition, an optical-to-THz per-pulse conversion efficiency of 6.41 × 10^-3 can be achieved by a localized THz resonant cavity design. The enhanced optical-to-THz per-pulse conversion efficiency and THz propagation, resonance, and radiation behavior revealed not only help to understand the on-chip THz transmission phenomena but provide a good potentiality for a THz-OEIC design to be applied in low power-consuming microfluidic-channel-based THz biosensing chips as well.