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- Hu, Qitao, et al.
(författare)
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Nanotransistor-based gas sensing with record-high sensitivity enabled by electron trapping effect in nanoparticles
- 2024
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Ingår i: Nature Communications. - : Springer Nature. - 2041-1723. ; 15:1
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Tidskriftsartikel (refereegranskat)abstract
- Highly sensitive, low-power, and chip-scale H2 gas sensors are of great interest to both academia and industry. Field-effect transistors (FETs) functionalized with Pd nanoparticles (PdNPs) have recently emerged as promising candidates for such H2 sensors. However, their sensitivity is limited by weak capacitive coupling between PdNPs and the FET channel. Herein we report a nanoscale FET gas sensor, where electrons can tunnel between the channel and PdNPs and thus equilibrate them. Gas reaction with PdNPs perturbs the equilibrium, and therefore triggers electron transfer between the channel and PdNPs via trapping or de-trapping with the PdNPs to form a new balance. This direct communication between the gas reaction and the channel enables the most efficient signal transduction. Record-high responses to 1–1000 ppm H2 at room temperature with detection limit in the low ppb regime and ultra-low power consumption of ∼300 nW are demonstrated. The same mechanism could potentially be used for ultrasensitive detection of other gases. Our results present a supersensitive FET gas sensor based on electron trapping effect in nanoparticles.
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| 2. |
- Xu, Zheqiang, 1994-, et al.
(författare)
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A Nanoribbon-Based Ion-Gated Lateral Bipolar Amplifier for Ion Sensing
- 2024
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Ingår i: IEEE Transactions on Electron Devices. - 0018-9383 .- 1557-9646. ; , s. 1-6
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Tidskriftsartikel (refereegranskat)abstract
- Nanoscale sensors usually produce feeble signals susceptible to inevitable external interference. Several signal amplification solutions exist for mitigating the interference. However, most nanoscale sensors are fabricated on silicon-on-insulator (SOI) substrate, which is not compatible with the integration process of traditional vertical bipolar amplifiers. This work presents an ion-gated lateral bipolar amplifier that integrates a nanoribbon filed-effect transistor (NRFET) ion sensor with a lateral bipolar junction transistor (LBJT), all on an SOI substrate, thereby greatly simplifying the fabrication process. The direct connection between the LBJT base and the NRFET source enables immediate amplification of the NRFET signal, minimizing exposure to surrounding interference. Characterized by a peak current gain exceeding 20, this amplifier design leads to a 3–7-fold enhancement in the overall signal-to-noise ratio (SNR) compared to a reference NRFET. Furthermore, this gain in SNR is empirically validated during pH sensing applications. The possibility of substrate biasing makes the integrated LBJT-NRFET amplifier unique as it can independently tune the current gain and reduce the noise thereby improving the SNR performance.
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