Issue 4, 2019

Thermoelectric terahertz photodetectors based on selenium-doped black phosphorus flakes

Abstract

Chemical doping of bulk black phosphorus is a well-recognized way to reduce surface oxidation and degradation. Here, we report on the fabrication of terahertz frequency detectors consisting of an antenna-coupled field-effect transistor (FET) with an active channel of Se-doped black phosphorus. Our devices show a maximum room-temperature hole mobility of 1780 cm2 V−1 s−1 in a SiO2-encapsulated FET. A room-temperature responsivity of 3 V W−1 was observed, with a noise-equivalent power of 7 nW Hz−1/2 at 3.4 THz, comparable with the state-of-the-art room-temperature photodetectors operating in the same frequency range. The inclusion of Se dopants in the growth process of black phosphorus crystals enables the optimization of the transport and optical performances of FETs in the far-infrared with a high potential for the development of BP-based electro-optical devices. We also demonstrate that the flake thickness can be tuned according to the target application. Specifically, thicker flakes (>80 nm) are suitable for applications in which high mobility and high speed are essential, thinner flakes (<10 nm) are more appropriate for applications requiring high on/off current ratios, while THz photodetection is optimal with flakes 30–40 nm thick, due to the larger carrier density tunability.

Graphical abstract: Thermoelectric terahertz photodetectors based on selenium-doped black phosphorus flakes

Supplementary files

Article information

Article type
Paper
Submitted
09 nov 2018
Accepted
26 dez 2018
First published
15 jan 2019

Nanoscale, 2019,11, 1995-2002

Thermoelectric terahertz photodetectors based on selenium-doped black phosphorus flakes

L. Viti, A. Politano, K. Zhang and M. S. Vitiello, Nanoscale, 2019, 11, 1995 DOI: 10.1039/C8NR09060B

To request permission to reproduce material from this article, please go to the Copyright Clearance Center request page.

If you are an author contributing to an RSC publication, you do not need to request permission provided correct acknowledgement is given.

If you are the author of this article, you do not need to request permission to reproduce figures and diagrams provided correct acknowledgement is given. If you want to reproduce the whole article in a third-party publication (excluding your thesis/dissertation for which permission is not required) please go to the Copyright Clearance Center request page.

Read more about how to correctly acknowledge RSC content.

Social activity

Spotlight

Advertisements