Terahertz antenna arrays with silicon micromachined-based microlens antenna and corrugated horns

We report on two silicon based antennas for future large-format THz focal plane imaging arrays. The silicon-based corrugated horn antenna shows return loss below 15 dB and antenna gain over 20 dB in the 320–360 GHz frequency band. The 1.9 THz silicon microlens antenna has been designed and microfabricated. The simulated 1.9 THz antenna shows good 2-D beam radiation pattern and aperture efficiencies around 85%. It is clear that the silicon-based corrugated horn antenna will work well below 1 THz. However, it would be difficult to fabricate such antennas at frequencies beyond 1 THz due to the requirement of thin silicon wafers which is difficult to handle during the microfabrication. On the other hand, silicon microlens antennas can work in the frequency range of 300 GHz–2 THz or even higher because of the excellent tolerances achievable with microfabrication techniques. One major advantage of these batch processing techniques is that one can get hundreds of antennas on a single microfabrication run, thus reducing fabrication cost and time.