In recent years strain engineering is proposed in chalcogenide superlattices (SLs) to shape in particular the switching functionality for phase change memory applications. This is possible in Sb2Te3/GeTe heterostructures leveraging on the peculiar behavior of Sb2Te3, in between covalently bonded and weakly bonded materials. In the present study, the structural and thermoelectric (TE) properties of epitaxial Sb2+xTe3 films are shown, as they represent an intriguing option to expand the horizon of strain engineering in such SLs. Samples with composition between Sb2Te3 and Sb4Te3 are prepared by molecular beam epitaxy. A combination of X-ray diffraction and Raman spectroscopy, together with dedicated simulations, allows unveiling the structural characteristics of the alloys. A consistent evaluation of the structural disorder characterizing the material is drawn as well as the presence of both Sb2 and Sb4 slabs is detected. A strong link exists among structural and TE properties, the latter having implications also in phase change SLs. A further improvement of the TE performances may be achieved by accurately engineering the intrinsic disorder. The possibility to tune the strain in designed Sb2+xTe3/GeTe SLs by controlling at the nanoscale the 2D character of the Sb2+xTe3 alloys is envisioned

Cecchi, S., Dragoni, D., Kriegner, D., Tisbi, E., Zallo, E., Arciprete, F., et al. (2019). Interplay between Structural and Thermoelectric Properties in Epitaxial Sb2+xTe3 Alloys. ADVANCED FUNCTIONAL MATERIALS, 29(2) [10.1002/adfm.201805184].

Interplay between Structural and Thermoelectric Properties in Epitaxial Sb2+xTe3 Alloys

Cecchi, Stefano
;
Dragoni, Daniele;Bernasconi, Marco;
2019

Abstract

In recent years strain engineering is proposed in chalcogenide superlattices (SLs) to shape in particular the switching functionality for phase change memory applications. This is possible in Sb2Te3/GeTe heterostructures leveraging on the peculiar behavior of Sb2Te3, in between covalently bonded and weakly bonded materials. In the present study, the structural and thermoelectric (TE) properties of epitaxial Sb2+xTe3 films are shown, as they represent an intriguing option to expand the horizon of strain engineering in such SLs. Samples with composition between Sb2Te3 and Sb4Te3 are prepared by molecular beam epitaxy. A combination of X-ray diffraction and Raman spectroscopy, together with dedicated simulations, allows unveiling the structural characteristics of the alloys. A consistent evaluation of the structural disorder characterizing the material is drawn as well as the presence of both Sb2 and Sb4 slabs is detected. A strong link exists among structural and TE properties, the latter having implications also in phase change SLs. A further improvement of the TE performances may be achieved by accurately engineering the intrinsic disorder. The possibility to tune the strain in designed Sb2+xTe3/GeTe SLs by controlling at the nanoscale the 2D character of the Sb2+xTe3 alloys is envisioned
Articolo in rivista - Articolo scientifico
molecular beam epitaxy; phase change materials; strain engineering; thermoelectric materials; Raman spectra
English
2019
29
2
1805184
partially_open
Cecchi, S., Dragoni, D., Kriegner, D., Tisbi, E., Zallo, E., Arciprete, F., et al. (2019). Interplay between Structural and Thermoelectric Properties in Epitaxial Sb2+xTe3 Alloys. ADVANCED FUNCTIONAL MATERIALS, 29(2) [10.1002/adfm.201805184].
File in questo prodotto:
File Dimensione Formato  
Cecchi-2019-Adv Funct Mater-VoR.pdf

Solo gestori archivio

Descrizione: Full paper
Tipologia di allegato: Publisher’s Version (Version of Record, VoR)
Dimensione 3 MB
Formato Adobe PDF
3 MB Adobe PDF   Visualizza/Apri   Richiedi una copia
Cecchi-2019-Adv Funct Mater-AAM.pdf

accesso aperto

Descrizione: Full paper
Tipologia di allegato: Author’s Accepted Manuscript, AAM (Post-print)
Dimensione 2.23 MB
Formato Adobe PDF
2.23 MB Adobe PDF Visualizza/Apri

I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.

Utilizza questo identificativo per citare o creare un link a questo documento: https://hdl.handle.net/10281/216646
Citazioni
  • Scopus 29
  • ???jsp.display-item.citation.isi??? 27
Social impact