Enhancement of Photosensitivity in a Low-Operating-Voltage Organic-Inorganic Bilayer Thin-Film Transistor by Using an Asymmetric Source-Drain Electrode
Journal article, 2024

A solution-processed inorganic-organic bilayer semiconductor channel-based red-light-sensitive thin-film transistor (TFT) has been fabricated by using an ion-conducting Li-Al2O3 gate dielectric that limits the operating voltage of this TFT within 2 V. In this device, a high-electron-mobility inorganic metal-oxide semiconductor (SnO2) was used as the primary charge transport layer, whereas the polymer (PIDT-2TPD) was used as the photoactive layer. To improve its red photosensitivity, an asymmetric work function source-drain (S-D) electrode was fabricated, which allows a selective carrier (electron or hole) injection and collection from the channel. Besides, the work function difference of this asymmetric S-D electrode generates a potential difference between electrodes that allows faster charge collection from the channel. As a consequence, the photosensitivity of this asymmetric S-D electrode TFT enhanced by ∼103 times under red illumination with respect to the symmetric S-D electrode TFT and the detectivity of this device increased ∼20 times. In addition, the on/off ratio of asymmetric TFT is 4 times greater than that of the symmetric TFT, whereas the subthreshold swing (SS) of this TFT is reduced from 200 to 144 mV/decade.

phototransistor

ion-conducting dielectric

asymmetric electrode

organic/inorganic bilayer channel

low operating voltage

Author

Pijush Kanti Aich

Banaras Hindu University

Zewdneh Genene Wolkeba

Chalmers, Chemistry and Chemical Engineering, Applied Chemistry

Utkarsh Pandey

Banaras Hindu University

Akhilesh Kumar Yadav

Banaras Hindu University

Ergang Wang

Chalmers, Chemistry and Chemical Engineering, Applied Chemistry

Bhola Nath Pal

Banaras Hindu University

ACS Photonics

2330-4022 (eISSN)

Vol. 11 9 3704-3712

Subject Categories

Chemical Engineering

DOI

10.1021/acsphotonics.4c00876

More information

Latest update

10/5/2024