Band-gap and strain engineering in GeSn alloys using post-growth pulsed laser melting.
J Phys Condens Matter
; 35(5)2022 Dec 14.
Article
de En
| MEDLINE
| ID: mdl-36395508
ABSTRACT
The pseudomorphic growth of Ge1-xSnxon Ge causes in-plane compressive strain, which degrades the superior properties of the Ge1-xSnxalloys. Therefore, efficient strain engineering is required. In this article, we present strain and band-gap engineering in Ge1-xSnxalloys grown on Ge a virtual substrate using post-growth nanosecond pulsed laser melting (PLM). Micro-Raman and x-ray diffraction (XRD) show that the initial in-plane compressive strain is removed. Moreover, for PLM energy densities higher than 0.5 J cm-2, the Ge0.89Sn0.11layer becomes tensile strained. Simultaneously, as revealed by Rutherford Backscattering spectrometry, cross-sectional transmission electron microscopy investigations and XRD the crystalline quality and Sn-distribution in PLM-treated Ge0.89Sn0.11layers are only slightly affected. Additionally, the change of the band structure after PLM is confirmed by low-temperature photoreflectance measurements. The presented results prove that post-growth ns-range PLM is an effective way for band-gap and strain engineering in highly-mismatched alloys.
Texte intégral:
1
Collection:
01-internacional
Base de données:
MEDLINE
Langue:
En
Journal:
J Phys Condens Matter
Sujet du journal:
BIOFISICA
Année:
2022
Type de document:
Article
Pays d'affiliation:
Allemagne