Beteiligte:
Oliva, Miriam;
Gao, Guanhui;
Luna, Esperanza;
Geelhaar, Lutz;
Lewis, Ryan B
Erschienen:
IOP Publishing, 2019
Erschienen in:
Nanotechnology, 30 (2019) 42, Seite 425601
Sprache:
Nicht zu entscheiden
DOI:
10.1088/1361-6528/ab3209
ISSN:
0957-4484;
1361-6528
Entstehung:
Anmerkungen:
Beschreibung:
Abstract Bi-containing III-V semiconductors constitute an exciting class of metastable compounds with wide-ranging potential optoelectronic and electronic applications. However, the growth of III-V-Bi alloys requires group-III-rich growth conditions, which pose severe challenges for planar growth. In this work, we exploit the naturally-Ga-rich environment present inside the metallic droplet of a self-catalyzed GaAs nanowire (NW) to synthesize metastable GaAs/GaAs1−x Bi x axial NW heterostructures with high Bi contents. The axial GaAs1−x Bi x segments are realized with molecular beam epitaxy by first enriching only the vapor–liquid–solid (VLS) Ga droplets with Bi, followed by exposing the resulting Ga-Bi droplets to As2 at temperatures ranging from 270 °C to 380 °C to precipitate GaAs1−x Bi x only under the NW droplets. Microstructural and elemental characterization reveals the presence of single crystal zincblende GaAs1−x Bi x axial NW segments with Bi contents up to (10 ± 2)%. This work illustrates how the unique local growth environment present during the VLS NW growth can be exploited to synthesize heterostructures with metastable compounds.