Improving the Stability of R2R Printed 1‐Bit Code Generator through Spin‐Coated Multilayer‐Encapsulation Method

Abstract

Roll‐to‐roll (R2R) printed electronic devices have great advantages for developing large scale flexible and disposable devices when compared to current Si‐based technology. For practical realization of these advantages, however, R2R printed devices need to surmount device functionality limitations, most urgently high‐power dissipation and poor device stability. To resolve both imperative challenges at once, herein, an all R2R printed complementary metal‐oxide‐semiconductor (CMOS) 1‐bit code generator with spin‐coated multilayer encapsulation method is developed. In order to print CMOS devices by an all‐R2R gravure printing method, electrical amphoteric property of the single walled carbon nanotube (SWCNT) is utilized to fabricate both p‐type and n‐type SWCNT based thin film transistors (TFTs). In addition, printable encapsulating polymeric materials (CYTOP and FG‐3650) are developed to effectively prevent H2O permeation. The resulting CMOS 1‐bit code generator is able to continuously operate for 2 h under ambient conditions without any variation in output voltage and frequency.

Roll‐to‐Roll Gravure‐Printed Carbon Nanotube‐based Transistor Arrays for a Digital Column Chromatograph

“…The coated CYTOP is critical to maintaining the consistent electrical characteristics of the printed SWCNT-TFTs without any variation due to the trapped charge generated by contacting the coating layers on printed SWCNT. [14] The thicknesses of the gate electrode, dielectric layer, and drain-source electrodes were 0.51, 1.8, and 0.5 µm, respectively; almost same as previously reported. [26] Moreover, the operation frequency of the printed SWCNT-TFT was 60 Hz based on a register type inverter at an operational power of 10 V DC.…”

“…The coated CYTOP is critical to maintaining the consistent electrical characteristics of the printed SWCNT‐TFTs without any variation due to the trapped charge generated by contacting the coating layers on printed SWCNT. [ 14 ]…”

“…In this work, the R2R gravure-printed SWCNT-TFT array was implemented as a flexible chemical sensor array by coating fluoropolymer, CYTOP, [13,14] as an electret [15,16] on the top of the SWCNT-TFT. [17,18] The electret is a dielectric material with a quasi-permanent and macroscopic field on its surface.…”

Rapid Uniformity Analysis of Fully Printed SWCNT-Based Thin Film Transistor Arrays via Roll-to-Roll Gravure Process

“…The gate, dielectric, active, and drain-source layers were respectively printed through the R2R gravure printing process. The web tension and pressure of the impression rollers were maintained with accuracies of ±0.3 kgf and ±0.38 psi, respectively [ 15 ]. The control system for web tension and roll impression pressure from our previously reported setup was used without modification [ 15 , 16 ].…”

A Printed Wireless Triangle‐Wave Generator via a Smartphone

“…The detailed printing process and basic performance of the R2R‐printed CMOS ring oscillator were reported in a previous paper. [ 39 ] In addition, the optical image and circuit diagram of the printed CMOS ring oscillator, which consists of five p‐type transistors and five n‐type transistors, are shown in Figure S9, Supporting Information. With the all‐printed Ag−PEDOT/IGZO/carbon‐based rectenna, we were able to wirelessly operate the R2R‐printed CMOS ring oscillator to generate a triangle wave (±4 V) with 2 Hz through a smartphone's NFC carrier signal (Figure 5c).…”