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Title: Wavelength-selective ultraviolet (Mg,Zn)O photodiodes: Tuning of parallel composition gradients with oxygen pressure

Abstract

We report on ultraviolet photodiodes with integrated optical filter based on the wurtzite (Mg,Zn)O thin films. Tuning of the bandgap of filter and active layers was realized by employing a continuous composition spread approach relying on the ablation of a single segmented target in pulsed-laser deposition. Filter and active layers of the device were deposited on opposite sides of a sapphire substrate with nearly parallel compositional gradients. Ensure that for each sample position the bandgap of the filter layer blocking the high energy radiation is higher than that of the active layer. Different oxygen pressures during the two depositions runs. The absorption edge is tuned over 360 meV and the spectral bandwidth of photodiodes is typically 100 meV and as low as 50 meV.

Authors:
; ; ;  [1]
  1. Institut für Experimentelle Physik II, Fakultät für Physik und Geowissenschaften, Universität Leipzig, Linnéstraße 5, 04103 Leipzig (Germany)
Publication Date:
OSTI Identifier:
22590805
Resource Type:
Journal Article
Resource Relation:
Journal Name: Applied Physics Letters; Journal Volume: 108; Journal Issue: 24; Other Information: (c) 2016 Author(s); Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; ABLATION; ABSORPTION; ENERGY BEAM DEPOSITION; LASER RADIATION; LASERS; LAYERS; MILLI EV RANGE; OPTICAL FILTERS; PHOTODIODES; PULSED IRRADIATION; PULSES; SAPPHIRE; THIN FILMS; TUNING; ULTRAVIOLET RADIATION; WAVELENGTHS

Citation Formats

Zhang, Zhipeng, Wenckstern, Holger von, Lenzner, Jörg, and Grundmann, Marius. Wavelength-selective ultraviolet (Mg,Zn)O photodiodes: Tuning of parallel composition gradients with oxygen pressure. United States: N. p., 2016. Web. doi:10.1063/1.4954375.
Zhang, Zhipeng, Wenckstern, Holger von, Lenzner, Jörg, & Grundmann, Marius. Wavelength-selective ultraviolet (Mg,Zn)O photodiodes: Tuning of parallel composition gradients with oxygen pressure. United States. doi:10.1063/1.4954375.
Zhang, Zhipeng, Wenckstern, Holger von, Lenzner, Jörg, and Grundmann, Marius. 2016. "Wavelength-selective ultraviolet (Mg,Zn)O photodiodes: Tuning of parallel composition gradients with oxygen pressure". United States. doi:10.1063/1.4954375.
@article{osti_22590805,
title = {Wavelength-selective ultraviolet (Mg,Zn)O photodiodes: Tuning of parallel composition gradients with oxygen pressure},
author = {Zhang, Zhipeng and Wenckstern, Holger von and Lenzner, Jörg and Grundmann, Marius},
abstractNote = {We report on ultraviolet photodiodes with integrated optical filter based on the wurtzite (Mg,Zn)O thin films. Tuning of the bandgap of filter and active layers was realized by employing a continuous composition spread approach relying on the ablation of a single segmented target in pulsed-laser deposition. Filter and active layers of the device were deposited on opposite sides of a sapphire substrate with nearly parallel compositional gradients. Ensure that for each sample position the bandgap of the filter layer blocking the high energy radiation is higher than that of the active layer. Different oxygen pressures during the two depositions runs. The absorption edge is tuned over 360 meV and the spectral bandwidth of photodiodes is typically 100 meV and as low as 50 meV.},
doi = {10.1063/1.4954375},
journal = {Applied Physics Letters},
number = 24,
volume = 108,
place = {United States},
year = 2016,
month = 6
}
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