Experimental Study on 100GHz Two-Step LIGA-based Vacuum Electron Devices

Summary form only given. Recent advances in MEMS technologies have enabled the miniaturization of conventional vacuum electron devices (VEDs) to the unprecedented level which conventional machining couldn´t reach. Sub micron precision provided by MEMS technologies together with VED´s superior characteristics to solid state devices such as the lack of ohmic loss and high breakdown strength is envisioning the realization of sub-THz and THz vacuum electronic devices with high efficiency and power-density. Our laboratory has adopted X-ray LIGA to achieve the required microstructures for high frequency VEDs such as folded-waveguide, coupled cavities, etc. Moreover, with two-step LIGA process, making fully LIGA-fabricated interaction circuits is now possible. We expect this approach to high frequency coherent radiation sources adopting modern micro-fabrication technologies might open a new era for vacuum electronic devices.