Extended-SWIR Photodetection in All-Group IV Core/Shell Nanowires
Abstract
Group IV Ge1-xSnx semiconductors hold the premise of enabling broadband silicon-integrated infrared optoelectronics due to their tunable bandgap energy and directness. Herein, we exploit these attributes along with the enhanced lattice strain relaxation in Ge/Ge0.92Sn0.08 core-shell nanowire heterostructures to implement highly responsive, room-temperature short-wave infrared nanoscale photodetectors. Atomic-level studies confirm the uniform shell composition and its higher crystallinity with respect to thin films counterparts. The demonstrated Ge/Ge0.92Sn0.08 p-type field-effect nanowire transistors exhibit superior optoelectronic properties achieving simultaneously a relatively high mobility, a high ON/OFF ratio, and a high responsivity, in addition to a broadband absorption in the short-wave infrared range. Indeed, the reduced bandgap of the Ge0.92Sn0.08 shell yields an extended cutoff wavelength of 2.1 um, with a room-temperature responsivity reaching 2.7 A/W at 1550 nm. These results highlight the potential of Ge/Ge1-xSnx core/shell nanowires as silicon-compatible building blocks for nanoscale integrated infrared photonics.
Keywords
Cite
@article{arxiv.2111.05994,
title = {Extended-SWIR Photodetection in All-Group IV Core/Shell Nanowires},
author = {Lu Luo and Simone Assali and Mahmoud R. M. Atalla and Sebastian Koelling and Anis Attiaoui and Gérard Daligou and Sara Martí and J. Arbiol and Oussama Moutanabbir},
journal= {arXiv preprint arXiv:2111.05994},
year = {2022}
}
Comments
22 pages, 4 figures, 1 Tables, 5 Supplementary information Figures