Benjamin S. Cook

An Origami Reconfigurable Axial-Mode Bifilar Helical Antenna

This communication presents a new reconfigurable origami bifilar helical antenna. This antenna can change its operating frequencies by changing its height. Also, analytical equations for the design of such antennas are derived based on an equivalent model of a standard helical antenna. An origami bifilar helical antenna is designed and its performance is verified using simulations and measurements.

Inkjet-printed 3D interconnects for millimeter-wave system-on-package solutions

This work outlines the development, fabrication, and measurement of fully inkjet-printed 3D interconnects for wireless mm-wave packaging solutions. Conductive silver nanoparticle and dielectric polymer-based inks are utilized to fabricate die attach, dielectric ramp, and CPW transmission line interconnect structures in order to interface a silicon die with a packaging substrate. Insertion and return loss are measured and compared with simulations over the range of 0-40 GHz. An inkjet-printed mm-wave bow-tie slot antenna is integrated with the IC die in order to highlight the highly versatile nature of this 3D interconnect technology for integration with emerging SoP technology.

Inkjet Printed High-Q RF Inductors on Paper Substrate With Ferromagnetic Nanomaterial

For the first time, high quality factor (Q), meander inductors are demonstrated utilizing inkjet-printing on organic paper substrates. Quality factors of up to 25, which is an order of magnitude greater than previous works, and inductance values of up to 8 nH are achieved. The high self-resonance frequency (SRF) of 8 GHz makes it possible for the inductors to be used in the 900 MHz and 2.4 GHz RFID bands, and in 5 GHz Wifi band. Furthermore, a study into the performance and miniaturization effects of inkjet-printing ferromagnetic nanomaterial onto the inductors shows increases in inductance of up to 5%. Applications for inkjet printed inductors include all-printed flexible and wearable filters, resonators, and microwave matching networks.

All-inkjet-printed microfluidics-based encodable flexible chipless RFID sensors

This paper proposes the first-of-its-kind microfluidics-based encodable and flexible chipless RFID sensors. The prototype, including the microfluidic channels and passive RFID resonators, is manufactured cost-efficiently with sole reliance on multilayer inkjet-printing for the first time. Three microfluidics-based reconfigurable spiral resonators are used to obtain tunable “code” frequencies and encode the RFID with less than 0.5 μL of water per bit. The embedded microfluidics also facilitate sensing of various fluids (e.g. identifying different water-glycerol mixtures). The proposed chipless RFID module maintains a stable performance during bending and can be bent for radii down to at least 12 mm. The proposed encodable chipless RFID module can be used in various application spaces including healthcare monitoring, food quality sensing and liquid leakage detection.

E-band characterization of 3D-printed dielectrics for fully-printed millimeter-wave wireless system packaging

This work explores the integration of 3D and inkjet printing manufacturing processes with millimeter-wave (mm-wave) wireless packaging technology. Stereolithography-based (SLA) 3D printing methods are discussed for two classes of materials: polymeric and ceramic-loaded dielectrics. 3D-printed materials are characterized for performance within the E-band wireless regime (55–95 GHz), extracting relative permittivity and loss tangent. Thermal cycling tests are performed in order to evaluate the thermal stress characteristics of the printed dielectrics structures. Die encapsulation with SLA printing technology is presented as an alternative to the standard molding and stamping technology. Inkjet printing is used to demonstrate the fabrication of metallic structures directly onto 3D-printed packages, highlighting potential applications of on-package antenna arrays, lenses, and metamaterial surfaces. Finally, inkjet-printed mm-wave transmission lines are realized on 3D-printed ramp structures, demonstrating efficient 3D interconnects with ramp slopes up to 65° for through-mold-via (TMV) solutions.