Enhanced performance of field-effect transistors based on C60 single crystals with conjugated polyelectrolyte

Abstract

Contact resistance at the interface between metal electrodes and semiconductors can significantly limit the performance of organic field-effect transistors, leading to a distinct voltage drop at the interface. Here, we demonstrate enhanced performance of n-channel field-effect transistors based on solution-grown C60 single-crystalline ribbons by introducing an interlayer of a conjugated polyelectrolyte (CPE) composed of poly [(9,9-bis(3′-((N,N-dimethyl)-N-ethylammonium)-propyl)-2,7-fluorene)-alt-2,7-(9,9-dioctylfluorene)] dibromide (PFN + Br − ). The PFN + Br − interlayer greatly improves the charge injection. Consequently, the electron mobility is promoted up to 5.60 cm 2 V −1 s −1 and the threshold voltage decreased dramatically with the minimum of 4.90 V.contact resistance, C60 single crystal, organic field-effect transistor, solution process Citation:

Crystallization from a Droplet: Single-Crystalline Arrays and Heterojunctions for Organic Electronics

“…Interfacial engineering to better align the energy level and new methods to process thinner single crystals can potentially improve the nonlinear behavior. 18,45 (5) With sophisticated device design and interfacial engineering, OFETs based on OSC single crystals have a good chance of leading the high-frequency study to above 100 MHz. 46,47 (6) Fine patterning techniques such as photolithography and e-beam lithography with OSC single crystals are combined to miniaturize the devices for potential integration.…”

“…(4) The charge injection in single-crystal-based OFETs is generally not efficient, which is part of the reason for the observed nonlinear transfer curves. Interfacial engineering to better align the energy level and new methods to process thinner single crystals can potentially improve the nonlinear behavior. , (5) With sophisticated device design and interfacial engineering, OFETs based on OSC single crystals have a good chance of leading the high-frequency study to above 100 MHz. , (6) Fine patterning techniques such as photolithography and e-beam lithography with OSC single crystals are combined to miniaturize the devices for potential integration. (7) With homogeneity from the molecular level to the millimeter or centimeter scale, large single crystals will exhibit excellent uniformity, allowing the construction of compact circuits based on a single crystal.…”

High electron mobility and tuneable glass transition temperature in fullerene-functionalized polynorbornenes

“…[18][19][20][21] The benefit of these modifications is apparent, considering that for most applications functionalized compounds are preferred over unfunctionalized C 60 , even though substitution of the fullerene using alkyl or solubilising groups can be considered to be a dilution of the electronically active structural unit. The significance of this trade-off is noticeable, if reported maximum OFET electron mobilities of unsubstituted C 60 (m e-max = 5-11 cm 2 V À1 s À1 ) [22][23][24] and a common substituted derivative, PCBM (m e-max = 0.05-0.21 cm 2 V À1 s À1 ) 4,25 are compared. The increased solubility of derivatives in organic solvents facilitates solution processing and eases incorporation in blend systems.…”

Monolayer organic field-effect transistors

“…OFET is one of the fundamental elements for organic circuits, and a powerful tool to characterize molecular semiconductor materials [5][6][7]. The performance of OFETs has witnessed great progress in the past 40 years, and the mobility has been improved to 10-40 cm 2 V −1 s −1 from 10 −6 -10 −5 cm 2 V −1 s −1 through the design of new materials and optimization of device fabrication processes [8][9][10][11][12][13][14][15]. However, some basic scientific issues are still unclear.…”