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A novel photodetecting device architecture that combines the optoelectronic property advantages of a perovskite and the amplification properties of a Si metal–oxide–semiconductor field‐effect transistor (MOSFET) to innovate a photodetecting system with ultrahigh sensitivity, especially in low‐light intensity, is demonstrated. This perovskite‐based MOSFET photodetector (PM‐PD) can respond as low as 116 nW cm−2with extremely high responsivity 4200 A W−1. The perovskite is part of the gate dielectric to modulate the MOSFET drain current when the light intensity is changed. A direct bandgap, organic–inorganic hybrid halide perovskite with a large optical absorption coefficient, can enhance photodetector performance. However, perovskite materials are not good conductors for transporting photogenerated electrons and holes compared with single‐crystal silicon. Therefore, the perovskite was utilized as a dielectric where the capacitance is used instead. In the proposed PM‐PD architecture, changing the width‐to‐length (W/L) ratio of perovskite capacitor electrodes, can modulate the dark current from picoamperes to microamperes providing a tunable parameter for optimizing photodetecting performance. Furthermore, the capacitance of the perovskite can be modulated by frequency, which facilitates matching the capacitance of perovskite and MOSFET gate oxide—another important requirement for optimal photodetecting performance. Finally, our novel PM‐PD is commensurate with potential 3D monolithic integration.
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Ultrasensitive UV Photodetector Based on Interfacial Charge-Controlled Inorganic Perovskite–Polymer Hybrid Structure
In this work, we demonstrate an ultrasensitive, visible-blind ultraviolet (UV) photodetector based on perovskite–polymer hybrid structure. A novel wide-band-gap vacancy-ordered lead-free inorganic perovskite Cs2SnCl6 with Nd3+ doping is employed in the active layer of this hybrid photodetector. Remarkably, with interfacial charge-controlled hole-injection operating mechanism, our device achieves a maximum detectivity of 6.3 × 1015 Jones at 372 nm, fast photoresponse speed with rise time and fall time in the order of milliseconds, and a large linear dynamic range of 118 dB. The performance is significantly better than most of the existing organic and inorganic semiconductor UV photodetectors reported so far, and its detectivity is close to 1 order of magnitude higher than that of the photomultiplication tube (PMT) in the UV region. In addition, the photodetector demonstrated excellent environmental stability, which is critical for commercial deployment of perovskite-based optoelectronic devices. The results presented in this work open a new route toward development of high-performance optoelectronic devices using perovskite-based hybrid nanomaterial systems.
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- Award ID(s):
- 1760404
- PAR ID:
- 10192115
- Date Published:
- Journal Name:
- ACS Applied Materials & Interfaces
- ISSN:
- 1944-8244
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1021/acsami.0c09890
