Nano CNC milling technology for terahertz vacuum electronic devices

To satisfy the growing interest in high power (∼1–200 W) THz sources, our research group has been working on various technologies to miniaturize vacuum electronic devices while keeping the power levels high and offering wide instantaneous bandwidth operation. We are exploring several methods for manufacturing 0.22 THz circuits including LIGA, silicon DRIE, and nano machining. Manufacturing circuits using micro-processing techniques allows multiple circuits to be made at a time, but the process is complex and requires perfection. On the other hand, nano machining allows for rapid prototyping of any circuit or coupler design. We were able to directly machine and test 0.22 THz circuits in various materials with transmission losses around 5–15 dB and with wide bandwidth.