Hybrid La₂O₃-cPVP Dielectric for Organic Thin Film Transistor Applications

Abstract

In this work, we have studied the electrical performance of cross-linked polyvinyl phenol (cPVP) modified lanthanum oxide (La2O3) bilayer dielectric film in pentacene thin film transistors (TFT). A simple spin-coating and room temperature operated cross-linking reaction of the hydroxyl moieties of PVP and the nitrogen groups of PMF were carried out to form the cross-linked PVP. The deposition of a thin 30 nm cPVP layer over the La2O3 layer provided a low leakage current (<10−7A/cm2), causing a reduction in the interface trap density. Besides, the modified surface properties of the La2O3 layer were favorable for the growth of pentacene organic semiconductors. As a result, the current on-off ratio and the sub-threshold slope was improved from 104 and 1.0 V/decade to 105 and 0.67 V/decade. The La2O3∕cPVP pentacene TFT operated at −10 V also exhibited improvement in the field-effect mobility to 0.71 cm2/Vs from 0.48 cm2/Vs for the single-layer La2O3 (130 nm) device. Thus, our work demonstrates that the rare earth oxide La2O3 with cPVP is an excellent dielectric system in the context of emerging transistors with hybrid polymer gate dielectrics.

Review—Advancements and Perspectives of Organic LED: In Depth Analysis of Architectural Design, Characteristics Parameters, Fabrication Techniques, and Applications

“…141 The utilization of organic TFTs promises lowcost fabrication for large area applications. [142][143][144][145] This section will discuss the structural analysis of OTFTs. Table VII is illustrating the various structures of OTFT such as planer, dual gate, vertical and cylindrical OTFTs.…”

A Sub‐20 nm Organic/Inorganic Hybrid Dielectric for Ultralow‐Power Organic Thin‐Film Transistor (OTFT) With Enhanced Operational Stability

“…As an alternative, organic/inorganic hybrid dielectric layers where polymer films were utilized as organic layers have also been suggested (Table S1, Supporting Information). [27][28][29][30][31][32][33][34][35][36][37][38] Polymeric layers with reliable insulating properties can provide a favorable interface with organic semiconductors, and thus, high-performance OTFTs have been demonstrated therewith. [41] Moreover, one of the most important advantages obtained from the polymer/inorganic hybrid layers is the improved operational stability of OTFTs.…”

“…[ 16,17 ] Along this line, various types of organic and inorganic hybrid dielectric materials have been investigated extensively to exploit the advantages from both organic and inorganic dielectric materials. [ 6,18–38 ] For example, inorganic dielectric materials such as aluminum oxide (AlO x ) and hafnium oxide (HfO x ) generally exhibited high dielectric constant as well as outstanding dielectric strength. [ 39 ] However, the abundant amount of hydroxyl groups on the surface of the oxide layer often generates unwanted trap sites, which thus impair the OTFT performance.…”

Design of Organic Thin Film Transistor Using Tri-Layer dielectric polymers to enhance the electrical performance

“…[4] Single crystals with few structural aws have often shown the best mobility among small molecule semiconductors. [5] Although single-crystalline organic semiconductors have outstanding electrical performance, large-scale device circuitry design using single crystals faces greater computational challenges due to the problems of increasing uniform crystals and placing them in a consistent manner along with the massive number of devices [6]. As a result, existing organic electronics fabrication solutions rely on solution processing, including inkjet printing, to produce thin semiconductor materials with good crystallinity and precise crystal size and orientation.…”

“…To overcome these issues, a tri-layered dielectric polymer is introduced in the designed model [7]. Tri-layer polymers are used in the OTFT for strong, stiff, low friction, chemically resistant, enhanced thermal/humidity and frequency stability [5]. The tri-layered dielectric polymer used in the designed model is silicon dioxide (SiO2), Polyetherimide -Epoxy polymer (PEI-EP)/ polyoxymethylene homopolymer (POM-H).…”