Fully inkjet-printed three-dimensional(3D)objects with integrated metal provide exciting possibilities for on-demand fabrication of radio frequency electronics such as inductors,capacitors,and filters.To date,there ha...Fully inkjet-printed three-dimensional(3D)objects with integrated metal provide exciting possibilities for on-demand fabrication of radio frequency electronics such as inductors,capacitors,and filters.To date,there have been several reports of printed radio frequency components metallized via the use of plating solutions,sputtering,and low-conductivity pastes.These metallization techniques require rather complex fabrication,and do not provide an easily integrated or versatile process.This work utilizes a novel silver ink cured with a low-cost infrared lamp at only 80℃,and achieves a high conductivity of 1×10^(7) S m^(−1).By inkjet printing the infrared-cured silver together with a commercial 3D inkjet ultraviolet-cured acrylic dielectric,a multilayer process is demonstrated.By using a smoothing technique,both the conductive ink and dielectric provide surface roughness values of <500 nm.A radio frequency inductor and capacitor exhibit state-of-the-art quality factors of 8 and 20,respectively,and match well with electromagnetic simulations.These components are implemented in a lumped element radio frequency filter with an impressive insertion loss of 0.8 dB at 1 GHz,proving the utility of the process for sensitive radio frequency applications.展开更多
Smart materials that can change their properties based on an applied stimulus are in high demand due to their suitability for reconfigurable electronics,such as tunable filters or antennas.In particular,materials that...Smart materials that can change their properties based on an applied stimulus are in high demand due to their suitability for reconfigurable electronics,such as tunable filters or antennas.In particular,materials that undergo a metal–insulator transition(MIT),for example,vanadium dioxide(VO 2)(M),are highly attractive due to their tunable electrical and optical properties at a low transition temperature of 68°C.Although deposition of this material on a limited scale has been demonstrated through vacuum-based fabrication methods,its scalable application for large-area and high-volume processes is still challenging.Screen printing can be a viable option because of its high-throughput fabrication process on flexible substrates.In this work,we synthesize high-purity VO 2(M)microparticles and develop a screen-printable VO 2 ink,enabling the large-area and high-resolution printing of VO 2 switches on various substrates.The electrical properties of screen-printed VO 2 switches at the microscale are thoroughly investigated under both thermal and electrical stimuli,and the switches exhibit a low ON resistance of 1.8 ohms and an ON/OFF ratio of more than 300.The electrical performance of the printed switches does not degrade even after multiple bending cycles and for bending radii as small as 1mm.As a proof of concept,a fully printed and mechanically flexible band-pass filter is demonstrated that utilizes these printed switches as reconfigurable elements.Based on the ON and OFF conditions of the VO 2 switches,the filter can reconfigure its operating frequency from 3.95 to 3.77 GHz without any degradation in performance during bending.展开更多
文摘Fully inkjet-printed three-dimensional(3D)objects with integrated metal provide exciting possibilities for on-demand fabrication of radio frequency electronics such as inductors,capacitors,and filters.To date,there have been several reports of printed radio frequency components metallized via the use of plating solutions,sputtering,and low-conductivity pastes.These metallization techniques require rather complex fabrication,and do not provide an easily integrated or versatile process.This work utilizes a novel silver ink cured with a low-cost infrared lamp at only 80℃,and achieves a high conductivity of 1×10^(7) S m^(−1).By inkjet printing the infrared-cured silver together with a commercial 3D inkjet ultraviolet-cured acrylic dielectric,a multilayer process is demonstrated.By using a smoothing technique,both the conductive ink and dielectric provide surface roughness values of <500 nm.A radio frequency inductor and capacitor exhibit state-of-the-art quality factors of 8 and 20,respectively,and match well with electromagnetic simulations.These components are implemented in a lumped element radio frequency filter with an impressive insertion loss of 0.8 dB at 1 GHz,proving the utility of the process for sensitive radio frequency applications.
文摘Smart materials that can change their properties based on an applied stimulus are in high demand due to their suitability for reconfigurable electronics,such as tunable filters or antennas.In particular,materials that undergo a metal–insulator transition(MIT),for example,vanadium dioxide(VO 2)(M),are highly attractive due to their tunable electrical and optical properties at a low transition temperature of 68°C.Although deposition of this material on a limited scale has been demonstrated through vacuum-based fabrication methods,its scalable application for large-area and high-volume processes is still challenging.Screen printing can be a viable option because of its high-throughput fabrication process on flexible substrates.In this work,we synthesize high-purity VO 2(M)microparticles and develop a screen-printable VO 2 ink,enabling the large-area and high-resolution printing of VO 2 switches on various substrates.The electrical properties of screen-printed VO 2 switches at the microscale are thoroughly investigated under both thermal and electrical stimuli,and the switches exhibit a low ON resistance of 1.8 ohms and an ON/OFF ratio of more than 300.The electrical performance of the printed switches does not degrade even after multiple bending cycles and for bending radii as small as 1mm.As a proof of concept,a fully printed and mechanically flexible band-pass filter is demonstrated that utilizes these printed switches as reconfigurable elements.Based on the ON and OFF conditions of the VO 2 switches,the filter can reconfigure its operating frequency from 3.95 to 3.77 GHz without any degradation in performance during bending.
