Comparative analysis on DRIE and LIGA fabrications for millimeter-wave backward-wave oscillators

For the generation of millimeter wave from vacuum electron devices, the microfabrication of an interaction circuit is one of the key factors. Two different technologies, a deep etch x-ray lithography (x-ray LIGA) and a deep reactive ion etching (DRIE), were employed for the comparative study and the realization of a backward-wave oscillator. Both methods showed accurate and reliable results, which enabled the integration of the interaction circuit for millimeter-wave backward-wave oscillators.