An Electroactive Binder in the Formulation of IGZO Ink to Print an IGZO‐Based Rectifier for Harvesting Direct Current (DC) Power from the Near Field Communication (NFC) Signal of a Smartphone

Abstract

are fabricated by incorporating the vacuum deposition and printing methods utilizing pentacene at 869 MHz, C60 and pentacene at 300 MHz, C60 and tungsten oxide at 800 MHz and indium gallium zinc oxide (IGZO) at 16.7 GHz, respectively. [5][6][7][8] However, due to the weak nature of the signal generated from the smartphone (<1.5 Vpp), none of the aforementioned rectifiers were able to successfully interlock with the smartphone NFC signal. Furthermore, although all roll-to-roll (R2R) printed inorganic ZnO-PAN (polyaniline)-based diodes were reported to wirelessly transmit the operation power to the passive NFC sensor tag using 13.56 MHz, the rectifying efficiency was held to under 50%. [2][3][4] For the ultra high frequency region, in recent years, the printed silicon microparticles-based diodes have demonstrated the ability to interlock with smartphones using a 1.6 GHz signal. [9,10] However, in spite of the aforementioned achievements in rectifier fabrication, DC power harvesting from the coupled NFC signal of smartphones has not been demonstrated yet due to the high turn-on voltage and low rectifying efficiency of the printed diodes. [3,9,10] As such is the case, in order to harvest DC power with greater than 50% efficiency from the weak NFC signal (<1.5 Vpp) of smartphones, printed flexible rectifiers using high-performing semiconducting ink is still imperative in order to develop cost-effective and flexible NFC-sensor devices capable of interlocking with smartphones.The gravure, among well-known scalable printing methods, has been relatively well explored in terms of practicality in printing the rectifying diodes and thin film transistor (TFT)based devices. The method enables the resolution and reliability of overlay printing registration accuracy to be able to be maintained on printed patterns up to ±20 µm. [11] Therefore, in this work, the gravure method has been extensively explored in order to print a Schottky diode for the fabrication of a rectifier able to harvest DC power from the NFC signal of the smartphone. In order to employ the gravure method in printing the Schottky diode, the formulation of semiconducting ink is the most crucial step. The semiconducting layers should be able to render the Ohmic contacts solely with printed silver electrodes, as only silver nanoparticle-based gravure ink is commercially available. Furthermore, the semiconducting ink needs to have an appropriate viscosity and wetting property in order to print a homogeneous Formulating a high-performing semiconducting ink is crucial toward printing a diode for constructing a direct current (DC) power harvesting device, consisting of an antenna, a diode, and a capacitor, that can rectify the coupled weak near field communication (NFC) (13.56 MHz) signal (<1.5 Vpp) generated from smartphones. To achieve such performance, indium gallium zinc oxide (IGZO)-based semiconducting ink is formulated by developing an electroactive binder, poly(4-styrene sulfonic acid). By reducing the turn-on voltage and providing a good rheological character...

Bridging R2R Printed Wireless 1 Bit‐Code Generator with an Electrophoretic QR Code Acting as WORM for NFC Carrier Enabled Authentication Label

“…To couple the maximum AC voltage, the lowest resistance on the printed antenna should be attained. [34,35] However, Si-based diode is small and power enough for rectifying NFC carrier signal. This extra curing process at a higher temperature can be replaced by attaching a photocuring unit into the R2R gravure system in order to achieve a continuous R2R gravure printing system able to be utilized in a practical manufacturing line.…”

Printed Four Key‐Device Units for Unified Platform of Wireless Anti‐Counterfeiting Label to Bridge in Blockchain

“…All rectenna was printed by developing an IGZO ink which made a Schottky junction to the printed PEDOT:PSS electrode to harvest DC power from the NFC carrier signal. [ 29 ] The rectified DC 10 V was charged in the printed supercapacitors to provide DC power for 2–3 s while the NFC signal from the smartphone was inactive for 2 s. The 1‐bit chip was R2R printed by integrating a CMOS‐like oscillator and two inverter buffers to generate a 1‐bit signal, “1” (+10 V) and “0” (−10 V) operated by the wirelessly transmitted DC power. The 1‐bit code generator can be expandable to 4‐bit [ 30 ] or more through the R2R printing method.…”

“…The basic synthetic process and ink formulation for preparing an IGZO semiconducting ink are similar to the previously reported procedure. [ 29 ] First, the IGZO solution was attained based on the same procedures to the reported procedure [ 29 ] and formulated into gravure inks by adding the mixture into solution with 1 wt% of Tween‐80 (Sigma‐Aldrich and used without further purification process) and 1.2 g of dimethyl sulfoxide (Sigma‐Aldrich) with 5 wt% of PVA (polyvinyl alchol, Mw 66,000, Daejung chemical company (Korea)). Carbon paste (Dozen TECH Korea DC‐15) for printing resistors was reformulated by adding polyethylene resin (Daejung Chemical Reagent Corp., Korea) based binder with diethylene glycol monoethyl ether acetate (Daejung Chemical Reagent Corp., Korea) as the solvent.…”

Smartphone-Enabled Personalized Diagnostics: Current Status and Future Prospects

“…A rectenna, or rectifying antenna, is an antenna coupled to a rectifying element [39], the simplest of which may be a diode. While printed diodes may be used [40], they are typically slower and present higher forward voltages than conventional diodes, which, due to the timescales of the (bio)chemical processes involved, may not be too problematic.…”