A Novel Reconfigurable CMOS Compatible Ka Band Bandstop Structure Using Split-Ring Resonators and Vanadium Dioxide (VO2) Phase Change Switches

The article presents the design, fabrication and characterization of a novel complementary metal-oxide-semiconductor (CMOS) compatible reconfigurable Ka band bandstop structure using split ring resonators (SRR) while employing the Vanadium Dioxide (VO
₂
) phase change (PC) thermally triggered transition. The work focuses on the VO
₂
thin film conductivity levels challenges on silicon dioxide (SiO
₂
)/ silicon (Si) substrates caused by the limited conductivity in the metallic state of the VO
₂
films versus their non-zero conductivity in the insulating state. We characterize first various samples of VO
₂
thin films deposited on SiO
₂
/Si substrates and present different fabricated filters responses with several VO
₂
switches dimensions. The filters show higher bandstop rejection levels than previously reported VO
₂
based CMOS compatible bandstop filters for the Ka band and displays a higher reconfigurable range from: 29.7 GHz-38.7 GHz. The filters while introducing a new compact tuning mechanism present the first VO
₂
reconfigurable SRR bandstop structures for the Ka band.