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Abstract New deposition techniques for amorphous oxide semiconductors compatible with silicon back end of line manufacturing are needed for 3D monolithic integration of thin‐film electronics. Here, three atomic layer deposition (ALD) processes are compared for the fabrication of amorphous zinc tin oxide (ZTO) channels in bottom‐gate, top‐contact n‐channel transistors. As‐deposited ZTO films, made by ALD at 150–200 °C, exhibit semiconducting, enhancement‐mode behavior with electron mobility as high as 13 cm2V−1s−1, due to a low density of oxygen‐related defects. ZTO deposited at 200 °C using a hybrid thermal‐plasma ALD process with an optimal tin composition of 21%, post‐annealed at 400 °C, shows excellent performance with a record high mobility of 22.1 cm2V–1s–1and a subthreshold slope of 0.29 V dec–1. Increasing the deposition temperature and performing post‐deposition anneals at 300–500 °C lead to an increased density of the X‐ray amorphous ZTO film, improving its electrical properties. By optimizing the ZTO active layer thickness and using a high‐kgate insulator (ALD Al2O3), the transistor switching voltage is lowered, enabling electrical compatibility with silicon integrated circuits. This work opens the possibility of monolithic integration of ALD ZTO‐based thin‐film electronics with silicon integrated circuits or onto large‐area flexible substrates.
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Ionic liquid gated poly(triaryl amine) thin film field effect transistor
Abstract A poly(triaryl amine) thin film field effect transistor was investigated in air with ionic liquid (IL) gating for the first time. The transistor retained a high‐on/off ratio of ~700 and mobility of ~10−2cm2/V‐s. When compared to a transistor based on the conducting polymer polyaniline under similar operating conditions, it was found to exhibit superior performance. Significantly low‐operating voltages (±1 V) enhances the possibility of its use in organic electronics. The device was successfully tested for binary operation, and we demonstrate its suitability for use in low‐power consumption electronic circuits.
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- Award ID(s):
- 1800262
- PAR ID:
- 10453597
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Journal of Applied Polymer Science
- Volume:
- 138
- Issue:
- 18
- ISSN:
- 0021-8995
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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