Evaporated Sex Te1- x Thin Films with Tunable Bandgaps for Short-Wave Infrared Photodetectors
© 2020 Wiley-VCH GmbH.
Veröffentlicht in: | Advanced materials (Deerfield Beach, Fla.). - 1998. - 32(2020), 38 vom: 23. Sept., Seite e2001329 |
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1. Verfasser: | |
Weitere Verfasser: | , , , , , , , , , , |
Format: | Online-Aufsatz |
Sprache: | English |
Veröffentlicht: |
2020
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Zugriff auf das übergeordnete Werk: | Advanced materials (Deerfield Beach, Fla.) |
Schlagworte: | Journal Article SexTe1-x thin films focal plane arrays photodetectors short-wave infrared tunable bandgaps |
Zusammenfassung: | © 2020 Wiley-VCH GmbH. Semiconducting absorbers in high-performance short-wave infrared (SWIR) photodetectors and imaging sensor arrays are dominated by single-crystalline germanium and III-V semiconductors. However, these materials require complex growth and device fabrication procedures. Here, thermally evaporated Sex Te1- x alloy thin films with tunable bandgaps for the fabrication of high-performance SWIR photodetectors are reported. From absorption measurements, it is shown that the bandgaps of Sex Te1- x films can be tuned continuously from 0.31 eV (Te) to 1.87 eV (Se). Owing to their tunable bandgaps, the peak responsivity position and photoresponse edge of Sex Te1- x film-based photoconductors can be tuned in the SWIR regime. By using an optical cavity substrate consisting of Au/Al2 O3 to enhance its absorption near the bandgap edge, the Se0.32 Te0.68 film (an optical bandgap of ≈0.8 eV)-based photoconductor exhibits a cut-off wavelength at ≈1.7 μm and gives a responsivity of 1.5 AW-1 and implied detectivity of 6.5 × 1010 cm Hz1/2 W-1 at 1.55 μm at room temperature. Importantly, the nature of the thermal evaporation process enables the fabrication of Se0.32 Te0.68 -based 42 × 42 focal plane arrays with good pixel uniformity, demonstrating the potential of this unique material system used for infrared imaging sensor systems |
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Beschreibung: | Date Revised 22.02.2021 published: Print-Electronic Citation Status PubMed-not-MEDLINE |
ISSN: | 1521-4095 |
DOI: | 10.1002/adma.202001329 |