UV-LIGA and DRIE grating microfabrication and testing for sheet beam amplifiers at 220 GHz

Slow-wave sheet beam amplifiers are under development at NRL to demonstrate 50 watts CW at 220 GHz. We report on the microfabrication of amplifier gratings based on Ultraviolet Lithography (UV-LIGA) techniques using the SU-8 Photoresist for thick films. Deep Reactive Ion etching (DRIE) has also been investigated for grating circuits. An improved cold test fixture is being developed for the cold test process.