Combination of Polymer Gate Dielectric and Two-Dimensional Semiconductor for Emerging Field-Effect Transistors

Abstract

Two-dimensional (2D) materials are considered attractive semiconducting layers for emerging field-effect transistors owing to their unique electronic and optoelectronic properties. Polymers have been utilized in combination with 2D semiconductors as gate dielectric layers in field-effect transistors (FETs). Despite their distinctive advantages, the applicability of polymer gate dielectric materials for 2D semiconductor FETs has rarely been discussed in a comprehensive manner. Therefore, this paper reviews recent progress relating to 2D semiconductor FETs based on a wide range of polymeric gate dielectric materials, including (1) solution-based polymer dielectrics, (2) vacuum-deposited polymer dielectrics, (3) ferroelectric polymers, and (4) ion gels. Exploiting appropriate materials and corresponding processes, polymer gate dielectrics have enhanced the performance of 2D semiconductor FETs and enabled the development of versatile device structures in energy-efficient ways. Furthermore, FET-based functional electronic devices, such as flash memory devices, photodetectors, ferroelectric memory devices, and flexible electronics, are highlighted in this review. This paper also outlines challenges and opportunities in order to help develop high-performance FETs based on 2D semiconductors and polymer gate dielectrics and realize their practical applications.

Vertical Halide Segregation and Stability of Two-Dimensional Layered Perovskite Nanostructures: Implications for Optoelectronic Devices

“…For instance, BA 2 PbI 4 ( n = 1) exhibits a band gap of 2.38 eV, while BA 2 MA 3 Pb 4 I 13 ( n = 4) has a decreased band gap of 1.6 eV . The layer number ( n ) determines the band gap, exciton binding energy, absorption/emission characteristics, and carrier lifetime of 2D perovskites. − These properties facilitate the broad application of 2D lead halide perovskites in optoelectronic devices, including solar cells, photodetectors, , light-emitting diodes, and field effect transistors . Furthermore, introducing halide ion substitutions or mixtures offers an additional route to adjust the band gap of both 2D and 3D halide perovskite materials. − However, due to the partial replacement of iodine (I) ions by bromine (Br) ions, the migration of ions in halide perovskites poses challenges to stabilizing the performance of perovskite-based optical devices. − …”

“…16−21 These properties facilitate the broad application of 2D lead halide perovskites in optoelectronic devices, including solar cells, 22 photodetectors, 23,24 light-emitting diodes, 25 and field effect transistors. 26 Furthermore, introducing halide ion substitutions or mixtures offers an additional route to adjust the band gap of both 2D and 3D halide perovskite materials. 27−31 However, due to the partial replacement of iodine (I) ions by bromine (Br) ions, the migration of ions in halide perovskites poses challenges to stabilizing the performance of perovskite-based optical devices.…”

Dielectric constant enhancement of poly 4-vinylphenol (PVPh) via graphene flakes incorporation through electrospray atomization for energy storage

“…The poly(4-vinylphenol) (PVPh)/graphene composite film combines the properties of both PVPh and graphene as a material with enhanced characteristics. 36 When graphene flakes incorporated into a PVPh matrix, the synergic effect of both makes PVPh/graphene composite a potential candidate for applications such as conductivity enhancement, mechanical reinforcement, thermal stability, barrier properties (hydrophilic nature), against moisture and gas permeation and for energy storage devices, typically supercapacitors (SCs) and lithium ion batteries (LIBs). 37 D. Roy 33 has applied PVPh/GO nanocomposite as dielectric thin film and studied the dielectric and leakage current properties at frequencies ranging from 1 kHz to 1 MHz.…”