Novel High Speed PCM Switch Based on Vanadium Dioxide With Less Than 500 ns Switching Time

This letter presents a new dc–67 GHz phase change material (PCM) based switch, with a maximum measured insertion loss (IL) of 0.6 dB and a switching speed of 483 ns. The topology inverts the typical layout of the four-terminal PCM switch. The alternative topology allows for the integration of high quality vanadium dioxide (VO<sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub>) thin films into a coplanar waveguide structure on a 430 <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$\mu $</tex-math> </inline-formula>m sapphire substrate. This inverted topology also utilizes a novel heat spreading oxynitride dielectric layer. The composition and deposition technique for the dielectric material prevent the VO<sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> from degrading during the fabrication of the integrated microheater structure. Subsequently, the fabricated single pole single throw (SPST) switch has 0.4dB of IL and 25 dB of isolation, at 60 GHz. The device has a P1dB of 29 dBm. The switch performance is compared with the state-of-the-art technologies, and it is shown to be well suited for millimeter wave (mmWave) applications.