Multifunctional Organic‐Semiconductor Interfacial Layers for Solution‐Processed Oxide‐Semiconductor Thin‐Film Transistor

Abstract

The stabilization and control of the electrical properties in solution-processed amorphous-oxide semiconductors (AOSs) is crucial for the realization of cost-effective, high-performance, large-area electronics. In particular, impurity diffusion, electrical instability, and the lack of a general substitutional doping strategy for the active layer hinder the industrial implementation of copper electrodes and the fine tuning of the electrical parameters of AOS-based thin-film transistors (TFTs). In this study, the authors employ a multifunctional organic-semiconductor (OSC) interlayer as a solution-processed thin-film passivation layer and a charge-transfer dopant. As an electrically active impurity blocking layer, the OSC interlayer enhances the electrical stability of AOS TFTs by suppressing the adsorption of environmental gas species and copper-ion diffusion. Moreover, charge transfer between the organic interlayer and the AOS allows the fine tuning of the electrical properties and the passivation of the electrical defects in the AOS TFTs. The development of a multifunctional solution-processed organic interlayer enables the production of low-cost, high-performance oxide semiconductor-based circuits.

Solution‐Processed Rad‐Hard Amorphous Metal‐Oxide Thin‐Film Transistors

“…In general, the high‐energy‐particle irradiation of oxide films degrades the film surface more significantly than the bulk owing to the facile generation of vacancies with unfilled coordination . A recent demonstration of the back‐channel defect passivation of solution‐processed TFTs, based on an oxide semiconductor with an organic semiconductor overlayer, successfully attained significant device stabilization relative to electrical defects and ambient species contamination . As shown in Figure a, the organic semiconductor passivation layer over the oxide semiconductor thin‐film could further stabilize the device performance when subjected to proton irradiation.…”

A Phosphonic Acid Self‐assembled Monolayer on UV‐Cured Metal Oxides as Gate Dielectrics for Low‐Voltage Organic Field‐Effect Transistors

“…Recently, organic field‐effect transistors (OFETs) have attracted great attention for their potential applications in future low‐cost electronics, including radio‐frequency identification (RFID) sensors and flexible displays . Despite advances in the past few decades, the large operating voltages of OFETs, reflecting the typically low mobilities of organic semiconductors, remain a critical issue that needs to be figured out .…”

Precise Patterning of Large‐Scale TFT Arrays Based on Solution‐Processed Oxide Semiconductors: A Comparative Study of Additive and Subtractive Approaches

“…To realize cost‐effective, large‐scale, and high throughput fabrication, solution‐based techniques (usually based on sol–gels) have also attracted significant interests, including spin‐coating, spray pyrolysis, bar‐coating, etc. The main problems for solution‐based techniques include the relatively high annealing temperature (>400 °C), the instability under various bias‐stressing, and effective patterning . Recently, the processing temperatures have been lowered in wide range of research, including photoassisted annealing, the water‐mediated photochemical treatment, and the high pressure assisted annealing .…”

“…Recently, the processing temperatures have been lowered in wide range of research, including photoassisted annealing, the water‐mediated photochemical treatment, and the high pressure assisted annealing . Moreover, stability of solution‐based devices has also been improved recently by using the organic interfacial layers . Despite substantive progress in printed oxide TFTS, there is relatively less research on patterning solution‐process oxide thin‐film transistor arrays.…”