Ge and Si Microcrystal Photodetectors with Enhanced Infrared Responsivity

Falcone, V., Barzaghi, A., Signorelli, F., Bergamaschini, R., Valente, J. , Paul, D. , Tosi, A. and Isella, G. (2023) Ge and Si Microcrystal Photodetectors with Enhanced Infrared Responsivity. In: 2023 IEEE Nanotechnology Materials and Devices Conference (NMDC), Paestum, Italy, 22-25 October 2023, ISBN 9798350335460 (doi: 10.1109/NMDC57951.2023.10343764)

Abstract

Ge and Si micro-crystals, grown on Si patterned substrates, can be used as absorbing elements for photodetection in the near-infrared. In such microstructures, light confinement effects due to crystal facet, enhance light absorption in the near-infrared as compared to conventional epitaxial layers. Devices based on single micro-crystals and on micro-crystals arrays have been fabricated and characterized. The photocurrent of Si photodetectors based on single micro-crystals have been measured in linear and avalanche regime, demonstrating a state-of-the-gain of ≈10 4. Ge-on-Si photodetectors based on micro-crystal arrays, fabricated using graphene as top contact, have also been fabricated, showing a responsivity in the 1500-1800 nm exceeding that of conventional planar devices.

• Item Type: Conference Proceedings
• Status: Published
• Refereed: Yes
• Glasgow Author(s) Enlighten ID: Paul, Professor Douglas and Valente, Dr Joao
• Authors: Falcone, V., Barzaghi, A., Signorelli, F., Bergamaschini, R., Valente, J., Paul, D., Tosi, A., and Isella, G.
• College/School: College of Science and Engineering > School of Engineering; College of Science and Engineering > School of Engineering > Electronics and Nanoscale Engineering
• ISSN: 2473-0718
• ISBN: 9798350335460
• Copyright Holders: Copyright © 2023 IEEE
• First Published: First published in 2023 IEEE Nanotechnology Materials and Devices Conference (NMDC)
• Publisher Policy: Reproduced in accordance with the publisher copyright policy