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Two-dimensional (2D) metal oxide semiconductors offer a superlative combination of high electron mobility and visible-range transparency uniquely suitable for flexible transparent electronics. Synthesis of these ultrathin (<3 nm) semiconductors by Cabrera-Mott oxidation of liquid metals could enable emerging device applications but requires the precise design of their electrostatics at the nanoscale. This study demonstrates sub-nanometer-level control over the thickness of semiconducting 2D antimony-doped indium oxide (AIO) by manipulating the kinetics of Cabrera-Mott oxidation through variable-speed liquid metal printing at plastic-compatible temperatures (175°C). By modulating both the growth kinetics and doping, we engineer the conductivity and crystallinity of AIO for integration in ultrathin channel transistors exhibiting exceptional steep turn-on, on-off ratios > 106 and an outstanding average mobility of 34.7 ± 12.9 cm2/Vs. This result shows the potential for kinetically controlling 2D oxide synthesis for various high-performance optoelectronic device applications.
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Decoding disorder: Machine learning unlocks multi-wavelength and intensity sensing in a single indium oxysulfide phototransistor
Not AvailableFlexible optoelectronic systems face fundamental challenges, including scalable synthesis of uniform, high-performance semiconductors and sensitivity to defects from large-area fabrication. Low-temperature deposition of perovskites, organics, and compound semiconductors promises tunable absorption but introduces structural disorder and sub-gap states that degrade device metrics. Here, we harness electronic disorder in printed sensors via machine learning to decode the photoresponse of three-terminal indium oxysulfide phototransistors fabricated by vacuum-free liquid metal interfacial synthesis. These devices combine wafer-scale uniformity with broadband visible absorption, achieving responsivities >100 A/W and detectivities approaching 7 × 1013 Jones. A cascaded classifier-regressor trained on gate-dependent photocurrent decodes illumination wavelengths (>95% accuracy) and intensities (10 μW/cm2–10 mW/cm2) from a single voltage sweep—without filters or device arrays. To our knowledge, this is the first phototransistor to extract both color and brightness simultaneously. Exploiting disorder to reveal latent information enables low-cost, single-device sensing and multi-parameter detection in flexible electronics.
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- PAR ID:
- 10664311
- Publisher / Repository:
- Cell Press
- Date Published:
- Journal Name:
- Device
- ISSN:
- 2666-9986
- Page Range / eLocation ID:
- 101023
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript
- Journal Article:
- https://doi.org/10.1016/j.device.2025.101023
