A 670 GHz Solid-State Multiplied Source with > 5mW Output Power Based on the Four-Port Prototype and 3D-Stacked Power-Combined Concept

We reported on the design, fabrication, and measurement of a solid-state frequency multiplied source providing over 5mW (@670.5 GHz) and 49mW (@342.8 GHz) output power at room temperature. This high power source benefits from the ultra-compact 3D-stacked power combined topology and novel four-port balanced prototype. The proposed four-port topology, featuring inherent suppressions on the odd- and 2N-order (where N is even) harmonics without any filter, can provide improved power-handling capability compared to the conventional three-port ones, while even increasing the conversion efficiency. On this basis, balanced doublers at 170 GHz and 340 GHz have been designed and optimized for high power operation. Moreover, a compact 3D-stacked configuration has been introduced to perform further power combining at 170 GHz, featuring doubled power handling capability and low decrease in efficiency. At room temperature, the achieved peak output power levels are 484mW at 166 GHz, 49.9mW at 342.8 GHz, and 5.52mW at 670.5 GHz. And the measured maximum conversion efficiencies are 35% at 173 GHz, 10% at 335 GHz, and 12% at 667 GHz, respectively.