Microfabrication of millimeter wave vacuum electron devices by two-step deep-etch x-ray lithography

Abstract

The circuits for millimeter wave vacuum electron devices with all circuit elements including an electron beam tunnel are microfabricated by two-step deep-etch x-ray lithography (x-ray LIGA). The discrepancies of eigenfrequency between experiment and simulation are within 1.1% in a coupled-cavity structure and 1.4% in a folded waveguide structure when the operating frequency is about 100GHz. Furthermore, a measured tolerance of below 2μm, and a measured surface roughness of 20–70nm, of LIGA-fabricated circuits implies the two-step LIGA microfabrication has potential applications up to the submillimeter wave region.

MM-wave to THz vacuum electron beam devices

“…In this context, we focus on UCD MEMS fabrication and RF testing (cold test) on 0.22 THz ultra wideband SBTWTA in the next section. Shin et al [11] at SNU were able to fabricate a circuit for a device that would operate at 100 GHz using two-step X-Ray LIGA process. Northrop Grumman fabricated a 220 GHz folded waveguide structure employing SU-8 LIGA process [12].…”

THz vacuum microelectronic devices

“…Broad wall dimension 1.80mm is achieved by joining two halves (top and bottom) each of height (h) 0.90mm. Each half of the circuit with half beam hole is fabricated using two-step LIGA process [8] that has been developed to construct three-dimensional microstructure with the beam tunnel. The beam tunnel is patterned in the middle of the slow wave structure during the second step.…”

Theory and simulation of a two-stage W-band multiple cavity klystron oscillator

“…In particular, a W-band two-stage klystron oscillator have been proposed [2,3]. Schematic of the oscillator is presented in Fig.…”