Conductive Bridging-Based Memristive RF Switches on a Silicon Substrate

Three RF switches and a phase shifter are proposed using the conductive bridging random access memory (CBRAM) technique. The fabrication process is developed with the Nafion membrane on a high-resistivity silicon substrate. The equivalent circuit model is established for each memristive RF switch. The proposed switches and the phase shifter have been validated by the good agreement achieved among the simulated, measured, and modeled results. The experimental results show that the series planar switch has the ON-state insertion loss (IL) below 1.69 dB and the OFF-state isolation over 25 dB up to 10 GHz, with the actuation voltages of 6.1~7.8/−1.5~−2 V. The parallel metal–insulator–metal (MIM) switch has the small ON-state IL below 0.45 dB and the OFF-state isolation over 18.4 dB when biased with 0.8~3.7/−0.5~−0.9 V. The series MIM switch has the ON-state IL below 0.61 dB and the OFF-state isolation over 21.9 dB with 0.7~2.3/−0.5~−0.9 V. The series MIM switch shows a good comprehensive performance of low actuation voltage, good uniformity, low IL, moderate isolation, and independent control. The phase shifter is realized with four series MIM switches, which provides a phase shift of 45° ± 5° from 3.8 to 4.3 GHz with the in-band IL of 2.25 dB. Compared with the conventional RF switchable devices, the proposed devices have the advantages of nonvolatility and low power consumption. Without depending on the electron beam lithography process and high-temperature phase change, the proposed technique is promising for reconfigurable RF circuits with mass production and feasibility to various substrates.