Interface Engineering in Organic Field-Effect Transistors: Principles, Applications, and Perspectives

Abstract

Heterogeneous interfaces that are ubiquitous in optoelectronic devices play a key role in the device performance and have led to the prosperity of today’s microelectronics. Interface engineering provides an effective and promising approach to enhancing the device performance of organic field-effect transistors (OFETs) and even developing new functions. In fact, researchers from different disciplines have devoted considerable attention to this concept, which has started to evolve from simple improvement of the device performance to sophisticated construction of novel functionalities, indicating great potential for further applications in broad areas ranging from integrated circuits and energy conversion to catalysis and chemical/biological sensors. In this review article, we provide a timely and comprehensive overview of current efficient approaches developed for building various delicate functional interfaces in OFETs, including interfaces within the semiconductor layers, semiconductor/electrode interfaces, semiconductor/dielectric interfaces, and semiconductor/environment interfaces. We also highlight the major contributions and new concepts of integrating molecular functionalities into electrical circuits, which have been neglected in most previous reviews. This review will provide a fundamental understanding of the interplay between the molecular structure, assembly, and emergent functions at the molecular level and consequently offer novel insights into designing a new generation of multifunctional integrated circuits and sensors toward practical applications.

Mechanical single-molecule potentiometers with large switching factors from ortho-pentaphenylene foldamers

“…A dvances of miniaturization in electronic devices unveil the possibility of adopting molecular electronics as primary elements in electronic circuity 1 . Plenty of molecules are extensively studied and employed as molecular wires, molecular switches, and molecular transistors 2,3 . Certain special electronic components like potentiometers that can reveal the displacementconductance relationship, and ultimately predict and control molecular conductance by external mechanical force, are of high importance but rarely developed.…”

Reconfigurable Multifunctional Ambipolar Polymer Transistors with Improved Switching-off Capability Upon Non-Uniformly Distributed Compensation Potential

“…The transistors based on pure PDPP-4FTVT and pure P2F films show similar tendency of on/off ratio increase after non-uniform charge injection ( Supplementary Fig. 10), which might be resulted from the trapped charges at the semiconductor/dielectric interface under biases 63 .…”

“…To demonstrate the universal applicability of this method for ambipolar transistors, p-type and n-type semiconductors stacked bi-layer ambipolar transistors were studied ( Supplementary Fig. 11), in which holes and electrons accumulate/transport in different layers 20,63 . Whether the transport channel is adjacent to or isolated from the electret layer, the non-uniformly injected charges can significantly reduce the off-state current and improve the on/off ratio.…”

Structured and functionalized organic semiconductors for chemical and biological sensors based on organic field effect transistors

“…6a) with a 2 nm-thick layer of calix [8]arene (C [8]A as shown in Fig. 6b) or C-methylcalix[4]-resorcinarene (CM [4]RA as shown in Fig. 6b) resulted in an increase in sensitivity toward ethyl acetate or isopropanol, respectively.…”

“…The velocity of charge carriers (holes or electrons for p-or n-type organic semiconductors, respectively) in OFETs is quantified by the field effect mobility, which is the most important parameter to characterize the performance of OFETs. OFETs are promising platforms for various types of sensors [1][2][3][4] with a unique combination of advantages. First, the electronic input and output characteristics of OFETs can be modulated by a variety of physical and chemical stimuli through different mechanisms.…”