A dedicated micromachining technology for high-aspect-ratio millimetre-wave circuits
Résumé
This paper presents a new technological process to implement efficient millimetre-wave passive circuits on a silicon substrate. This process associates a thick positive photoresist acting as a mould for the realization of thick conductors (several microns) with an ultra-thin dielectric membrane using only two layers (SiO2/Si2N3.8) in order to reduce both dielectric and ohmic losses in the coplanar millimetre-wave circuits. Coplanar transmission lines and a band-pass filter in the 30 GHz range, featuring respectively transmission losses lower than 0.2 and 1 dB, illustrate some potentialities of this process.