Biocompatible/Degradable Silk Fibroin:Poly(Vinyl Alcohol)-Blended Dielectric Layer Towards High-Performance Organic Field-Effect Transistor.

Xinming Zhuang,Xin Yang,Shijiao Han,Wei Huang,Junsheng Yu,Lu Li

doi:10.1186/s11671-016-1660-x

Abstract

Biocompatible silk fibroin (SF):poly(vinyl alcohol) (PVA) blends were prepared as the dielectric layers of organic field-effect transistors (OFETs). Compared with those with pure SF dielectric layer, an optimal threshold voltage of ~0 V, high on/off ratio of ~104, and enhanced field-effect mobility of 0.22 cm2/Vs of OFETs were obtained by carefully controlling the weight ratio of SF:PVA blends to 7:5. Through the morphology characterization of dielectrics and organic semiconductors by utilizing atom force microscopy and electrical characterization of the devices, the performance improvement of OFETs with SF:PVA hybrid gate dielectric layers were attributed to the smooth and homogeneous morphology of blend dielectrics. Furthermore, due to lower charge carrier trap density, the OFETs based on SF:PVA-blended dielectric exhibited a higher bias stability than those based on pure SF dielectric.Electronic supplementary materialThe online version of this article (doi:10.1186/s11671-016-1660-x) contains supplementary material, which is available to authorized users.

Highlights

Organic field-effect transistors (OFETs) have shown enormous development in the past few decades due to their potential use in large area sensor arrays, flat panel displays, and radio frequency identification [1,2,3]
It is well known that threshold voltage of OFET is strongly determined by the trap density (N) at the interface of dielectric and organic semiconductor of the device [31]
The trap density (N) at the interface of dielectric and organic semiconductor is proportional to sub-threshold slope (SS) and can be extracted by the Eq (1): SS 1⁄4 ðkT=qÞ ln10ð1 þ qN=CÞ

Summary

Introduction

Organic field-effect transistors (OFETs) have shown enormous development in the past few decades due to their potential use in large area sensor arrays, flat panel displays, and radio frequency identification [1,2,3]. While OFETs with high field-effect mobility (μ), low operating voltage, and good stability are essential for practical use, many researches were conducted to improve these parameters [4, 5]. Biological materials, such as silk fibroin (SF), chicken albumen, and gelatin, are emerging as potential solution-processed dielectric materials since they are biodegradable, biocompatible, environmentally friendly, natural abundant, and do not require complicated chemical synthesis [18,19,20]. SF is usually a thin film in an aqueous solution process; it offers a biologically derived and biocompatible analog to the synthetic polymer dielectrics

Methods

Results

Conclusion