Low-Power Flexible Organic Field-Effect Transistors with Solution-Processable Polymer-Ceramic Nanoparticle Composite Dielectrics.

Xiong Chen,Hao Zhang,Yu Zhang,Xiangfeng Guan,Dagui Chen,Zitong Zhang

doi:10.3390/nano10030518

Xiong Chen, Hao Zhang + Show 4 more

Open Access

https://doi.org/10.3390/nano10030518

Copy DOI

Abstract

Polymer-ceramic dielectric composites have been of great interest because they combine the processability of polymers with the desired dielectric properties of the ceramics. We fabricated a low voltage-operated flexible organic field-effect transistor (OFET) based on crosslinked poly (4-vinyl phenol) (PVP) polymer blended with novel ceramic calcium titanate nanoparticles (CaTiO3 NPs) as gate dielectric. To reduce interface roughness caused by nanoparticles, it was further coated with a very thin PVP film. The resulting OFET exhibited much lower operated voltage (reducing from –10.5 V to –2.9 V), a relatively steeper threshold slope (~0.8 V/dec) than those containing a pure PVP dielectric. This is ascribed to the high capacitance of the CaTiO3 NP-filled PVP insulator, and its smoother and hydrophobic dielectric surface proved by atomic force microscopy (AFM) and a water contact angle test. We also evaluated the transistor properties in a compressed state. The corresponding device had no significant degradation in performance when bending at various diameters. In particular, it operated well continuously for 120 hours during a constant bending stress. We believe that this technology will be instrumental in the development of future flexible and printed electronic applications.

Highlights

Given the emergence of electronics on skin/organs, rollable displays, printed radio-frequency identification (RFID) tags, electronic papers and wearable sensor, as well as the printability and potential in realizing low-cost and large-area electronic devices, devices with flexible and stretchable organic field-effect transistors (OFETs) have attracted significant attention in the development of next-generation thin-film electronics [1,2].one of the major challenges for OFETs has been the rather high voltages needed for their operation when the conventional SiO2 is used as the gate dielectrics, which is considered to suffer from its low dielectric constant (k~3.2) [3]
One of the major challenges for OFETs has been the rather high voltages needed for their operation when the conventional SiO2 is used as the gate dielectrics, which is considered to suffer from its low dielectric constant (k~3.2) [3]
When the SiO2 thickness is reduced to a nanoscale, the gate leakage current derived for the tunneling effect increases exponentially [6]

Summary

Introduction

Given the emergence of electronics on skin/organs, rollable displays, printed radio-frequency identification (RFID) tags, electronic papers and wearable sensor, as well as the printability and potential in realizing low-cost and large-area electronic devices, devices with flexible and stretchable organic field-effect transistors (OFETs) have attracted significant attention in the development of next-generation thin-film electronics [1,2]. One of the major challenges for OFETs has been the rather high voltages needed for their operation when the conventional SiO2 is used as the gate dielectrics, which is considered to suffer from its low dielectric constant (k~3.2) [3]. In order to reduce the operating voltage of OFETs, it is necessary to use a high k material and/or to reduce the thickness of the gate dielectric layer [4,5]. The combination of a solution-processable high dielectric constant BaTiO3 or BaSrTiO3 nanoparticle layer and other polymers for low-operated organic electronics were reported [13,14,15]. We fabricate low-voltage operated flexible OFETs with good performance and stability

Materials Synthetic

Device Fabrication

Conclusions