Wafer‐Scale Fabrication of High‐Performance n‐Type Polymer Monolayer Transistors Using a Multi‐Level Self‐Assembly Strategy

Abstract

Wafer‐scale fabrication of high‐performance uniform organic electronic materials is of great challenge and has rarely been realized before. Previous large‐scale fabrication methods always lead to different layer thickness and thereby poor film and device uniformity. Herein, the first demonstration of 4 in. wafer‐scale, uniform, and high‐performance n‐type polymer monolayer films is reported, enabled by controlling the multi‐level self‐assembly process of conjugated polymers in solution. Since the self‐assembly process happened in solution, the uniform 2D polymer monolayers can be facilely deposited on various substrates, and theoretically without size limitations. Polymer monolayer transistors exhibit high electron mobilities of up to 1.88 cm2 V−1 s−1, which is among the highest in n‐type monolayer organic transistors. This method allows to easily fabricate n‐type conjugated polymers with wafer‐scale, high uniformity, low contact resistance, and excellent transistor performance (better than the traditional spin‐coating method). This work provides an effective strategy to prepare large‐scale and uniform 2D polymer monolayers, which could enable the application of conjugated polymers for wafer‐scale sophisticated electronics.

Correlation between the static and dynamic responses of organic single-crystal field-effect transistors

“…Following various recent developments in printing technologies and in materials science, the mass production of highly integrated OSC devices is expected to lead to challenges in terms of the internet of things (IoT) challenges [13][14][15] . Recently, various groups have demonstrated the wafer-scale fabrication of ultra-thin single-crystal OSCs via a one-shot solution process [16][17][18][19][20][21][22][23][24][25][26][27] . The resulting excellent electronic properties, including a field-effect mobility up to 10 cm 2 V −1 s −1 originating from coherent band-like transport 20,27,28 , in conjunction with the miniaturization of organic field-effect transistor (OFET) devices, allows high-speed switching operations at a few tens of a MHz 20,29,30 .…”

Bottom-up supramolecular assembly in two dimensions

“…5C). 134,135 Other molecular designs have shown similar properties, 88,136 supporting the correlation between precise monomer packing parameters and the specific charge transport capabilities of the material. However, it is still unclear whether proton transport could benefit from a similar lattice effect in 2D systems.…”

Evolutionary 2D organic crystals for optoelectronic transistors and neuromorphic computing

“…Because of their wide spectral range of optoelectronic responsiveness, flexibility, and vast area processability, OSCs are interesting options for manufacturing high-performance optoelectronic devices and circuits [33,[40][41][42][43]. Reducing the thickness of organic crystals to a few layers or even a single monolayer improves performance in a variety of ways: (i) reduce contact resistance and Schottky barrier so that an ohmic contact can be achieved, as depicted in figures 2(c) and (d) [44][45][46][47], (ii) increase carrier mobility, as shown in figures 2(a) and (b) [45,[48][49][50][51][52][53][54][55][56], and (iii) achieve controllable growth [57]. Apart from the electrical advancements of transistors, obvious enhancement of internal photo-response in the application of 2D OCs-based optoelectronic transistor compared with that of the same bulk crystals, as shown in figures 2(e) and (f) [48].…”