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Abstract Organic doping is widely used for defining the majority charge carriers of organic thin films, tuning the Fermi level, and improving and stabilizing the performance of organic light‐emitting diodes and organic solar cells. However, in contrast to inorganic semiconductors, the doping concentrations commonly used are quite high (in the wt% range). Such high concentrations not only limit the scope of doping in organic field‐effect transistors (OFETs), but also limit the doping process itself resulting in a low doping efficiency. Here, the mechanism of doping at ultralow doping concentrations is studied. Doped C60metal‐oxide‐semiconductor (MOS) junctions are used to study doping at the 100 ppm level. With the help of a small‐signal drift‐diffusion model, it is possible to disentangle effects of traps at the gate dielectric/organic semiconductor interface from effects of doping and to determine the doping efficiency and activation energy of the doping process. Doped C60OFETs with an ultralow operation voltage of 800 mV and an excellent on/off ratio of up to 107are realized. The devices have low subthreshold swing in the range of 80 mV dec−1and a large transconductance of up to 8 mS mm−1.
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This content will become publicly available on February 2, 2026
Micro‐Engraving UV‐Sensitive Thin‐Film Transistor from Metal–Metal Oxide Nanoparticles with Band‐Gap Engineering
Abstract As known, n‐type inorganic semiconductor nanoparticles such as zinc oxide nanoparticles have been explored in various sensing applications, which demand high‐density electronic elements placement for rapid operation. Herein, high‐resolution designs of conductive channels of noble metal‐doped zinc oxide nanoparticles is demonstrated using an engraving transfer printing process and silver metal doping approach. Such thin‐film transistors with reduced feature size to 2 µm fabricated exhibited significantly enhanced electron mobility up 3.46 × 10−2cm2V−1s−1and light sensitivity. Furthermore, the integration of this micropatterning technology and metal doping in thin‐film transistors is utilized for control of current–voltage characteristics under the ultraviolet radiation with high sensitivity. It is suggested that this approach to design of doped inorganic nanoparticle channels paves the way for high‐density thin‐film transistors suitable for optoelectronic circuit, UV photodetectors and neuromorphic computing systems.
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- Award ID(s):
- 2203806
- PAR ID:
- 10598422
- Publisher / Repository:
- Adv. Electronic Materials
- Date Published:
- Journal Name:
- Advanced Electronic Materials
- ISSN:
- 2199-160X
- Subject(s) / Keyword(s):
- TFT UV-sensitive
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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