300-GHz On-Chip Complementary Source Antenna and Its Application to Silicon-Based Integrated Transmitter for Communication

In this paper, a 300-GHz on-chip complementary source antenna is first proposed for an integrated transmitter. By selectively removing the silicon substrate using the localized backside etching (LBE) process, the enhanced gain and stable performance are simultaneously realized for the proposed antenna. Moreover, differential monopoles and a dielectric resonator contribute to the electric and magnetic sources, respectively, leading to a wide operating bandwidth. Additionally, the introduction of copper package and differential excitations are investigated for surface wave suppression and radiation efficiency improvement, without any additional post-processing steps. The proposed antenna is fabricated in 130 nm SiGe process, and measurement results show a high gain of 9.0 dBi. Moreover, to realize long-distance wireless communication, a dual-channel transmitter with a lens is constructed. Different from the silicon-lens loading technique with low flexibility and bulky size, a solution integrating the on-chip antenna and low-loss Fresnel zone lens is proposed for significantly boosting the antenna gain and lowering the profile. The proposed transmitter is measured, and the results show a high EIRP of 30.8 dBm with a 3-dB bandwidth from 291 to 321 GHz. Furthermore, the wireless link is achieved using 16QAM modulation at a distance as long as 1.5 m, which demonstrates it a good candidate for terahertz point-to-point communication.