From Electric Doping Control to Thermal Defect Nucleation in Perovskites. Issue 34 (11th October 2022)

• Record Type: Journal Article
• Authors: Marinković, Stefan; Fernández‐Rodríguez, Alejandro; Fourneau, Emile; Cabero, Mariona; Wang, Hailin; Nguyen, Ngoc Duy; Gazquez, Jaume; Mestres, Narcís; Palau, Anna; Silhanek, Alejandro V.
• Is Part Of: Advanced materials interfaces. Volume 9:Issue 34(2022)
• Page Start: n/a
• Page End: n/a
• Publication Date: 2022-10-11
• Subjects: electromigration -- epitaxial perovskites -- oxygen diffusion -- plastic deformation; Materials science -- Periodicals; 620.11
• DOI: 10.1002/admi.202200953
• Languages: English
• ISSNs: 2196-7350

Abstract

Abstract: Simultaneous optical microscopy and electric transport measurements on La0.7 Sr0.3 MnO3 nanobridges, grown on SrTiO3 (STO), show direct evidence of directional oxygen vacancy migration under large voltage bias. Comparative study on discontinuous structures, with voltages applied across a micron‐scale gap, demonstrates that high electric fields induce electrolytic modifications confined to the anode. Extensive electromigration is shown to induce the formation of linear surface scars on the STO substrate, following well defined crystallographic directions. The reproducible triggering of these surface dislocations is demonstrated, unveiling their thermal rather than electrical origin and it is shown that they do not represent electroformed conduction channels. High‐resolution scanning transmission electron microscopy imaging reveals that the scars correspond to nanometer scale steps caused by (101) gliding planes in the STO caused by the proliferation of edge dislocations and local lattice expansion. These findings shed light on selective electrically‐controlled atom migration and its role in structural modification of functional oxides, opening a unique avenue for ionotronic device design. Abstract : The authors modulate the oxygen doping levels in La0.7 Sr0.3 MnO3 nanobridges grown on SrTiO3 (STO) substrates by means of electric current. The effects of the treatment extend beyond resistive switching to induce highly localized crystallographic defects in the STO substrate via heating.