Conductive Polymer-Assisted Metal Oxide Hybrid Semiconductors for High-Performance Thin-Film Transistors

Abstract

Metal oxide semiconductors doped with additional inorganic cations have insufficient electron mobility for nextgeneration electronic devices so strategies to realize the semiconductors exhibiting stability and high performance are required. To overcome the limitations of conventional inorganic cation doping to improve the electrical characteristics and stability of metal oxide semiconductors, we propose solution-processed high-performance metal oxide thin-film transistors (TFTs) by incorporating polyaniline (PANI), a conductive polymer, in a metal oxide matrix. The chemical interaction between the metal oxide and PANI demonstrated that the defect sites and crystallinity of the semiconductor layer are controllable. In addition, the change in oxygen-related chemical bonding of PANI-doped indium oxide (InO x ) TFTs induces superior electrical characteristics compared to pristine InO x TFTs, even though trace amounts of PANI are doped in the semiconductor. In particular, the average field-effect mobility remarkably enhanced from 15.02 to 26.58 cm 2 V −1 s −1 , the on/off current ratio improved from 10 8 to 10 9 , and the threshold voltage became close to 0 V actually from −7.9 to −1.4 V.

Analysis of the Annealing Budget of Metal Oxide Thin‐Film Transistors Prepared by an Aqueous Blade‐Coating Process

“…), [20][21][22][23] by organic bulk doping to intentionally frustrate the crystallization. [24][25][26] Nevertheless, most of the previous reports on solution-processed MO films utilize toxic solvents, which result as a potential threat to the environment. Liu et al reported the MO-TFTs by using an aqueous precursor solution and studied the annealing time and low temperature effect.…”

“…), [ 20–23 ] by organic bulk doping to intentionally frustrate the crystallization. [ 24–26 ] Nevertheless, most of the previous reports on solution‐processed MO films utilize toxic solvents, which result as a potential threat to the environment. Liu et al.…”

Multimode Operation of Organic–Inorganic Hybrid Thin-Film Transistors Based on Solution-Processed Indium Oxide Films

“…25 Boratto et al reported that the lowest unoccupied molecular orbital (LUMO) of the organic molecules can also act as trap states for electrons from the MO CBM. 26 In particular, by adding polyaniline (PANI) into the InO x precursor, Kim and coworkers 27 enhanced the overall electrical characteristic of MOTFTs, proving that conductive polymers could decrease the trap density in the InO x semiconductor by orbital overlapping.…”

“…Because of this, TIPS-pentacene increases the percolation for electrons, providing an electron pathway where the InO x films have structural defects or have voids. 27 In the hybrid films, TIPS-pentacene was deposited with controlled thicknesses by physical vapor deposition. We find that the addition of vacuum-deposited TIPS-pentacene to singly coated InO x films creates devices with mobilities that are otherwise only measured after three InO x coating steps.…”

“…TIPS-pentacene can act as an electron transfer material for the InO x films due to the near resonance between the InO x CBM and the TIPS-pentacene electron affinity (EA). Because of this, TIPS-pentacene increases the percolation for electrons, providing an electron pathway where the InO x films have structural defects or have voids . In the hybrid films, TIPS-pentacene was deposited with controlled thicknesses by physical vapor deposition.…”