Stoichiometric Bi(2)Se(3)topological insulator ultra-thin films obtained through a new fabrication process for optoelectronic applications
Artikel i vetenskaplig tidskrift, 2020

A new fabrication process is developed for growing Bi(2)Se(3)topological insulators in the form of nanowires/nanobelts and ultra-thin films. It consists of two consecutive procedures: first Bi(2)Se(3)nanowires/nanobelts are deposited by standard catalyst free vapour-solid deposition on different substrates positioned inside a quartz tube. Then, the Bi2Se3, stuck on the inner surface of the quartz tube, is re-evaporated and deposited in the form of ultra-thin films on new substrates at a temperature below 100 degrees C, which is of relevance for flexible electronic applications. The method is new, quick, very inexpensive, easy to control and allows obtaining films with different thickness down to one quintuple layer (QL) during the same procedure. The composition and the crystal structure of both the nanowires/nanobelts and the thin films are analysed by different optical, electronic and structural techniques. For the films, scanning tunnelling spectroscopy shows that the Fermi level is positioned in the middle of the energy bandgap as a consequence of the achieved correct stoichiometry. Ultra-thin films, with thickness in the range 1-10 QLs deposited on n-doped Si substrates, show good rectifying properties suitable for their use as photodetectors in the ultra violet-visible-near infrared wavelength range.

Författare

Matteo Salvato

Universita degli Studi di Roma Tor Vergata

Istituto Nazionale di Fisica Nucleare

Mattia Scagliotti

Universita degli Studi di Roma Tor Vergata

Istituto Nazionale di Fisica Nucleare

Maurizio De Crescenzi

Universita degli Studi di Roma Tor Vergata

Istituto Nazionale di Fisica Nucleare

Paola Castrucci

Universita degli Studi di Roma Tor Vergata

Istituto Nazionale di Fisica Nucleare

Fabio De Matteis

Universita degli Studi di Roma Tor Vergata

Michele Crivellari

Fondazione Bruno Kessler (FBK)

Stefano Pelli Cresi

Consiglio Nazionale delle Ricerche (CNR)

Daniele Catone

Consiglio Nazionale delle Ricerche (CNR)

Thilo Bauch

Chalmers, Mikroteknologi och nanovetenskap (MC2), Kvantkomponentfysik

Floriana Lombardi

Chalmers, Mikroteknologi och nanovetenskap (MC2), Kvantkomponentfysik

Nanoscale

2040-3364 (ISSN)

Vol. 12 23 12405-12415

High Frequency Topological Insulator devices for Metrology (HiTIMe)

Europeiska kommissionen (EU), 2018-02-01 -- 2022-01-31.

Ämneskategorier

Oorganisk kemi

Materialkemi

Den kondenserade materiens fysik

DOI

10.1039/d0nr02725a

PubMed

32490504

Mer information

Senast uppdaterat

2020-09-18