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Title: Electronic Transport and Ferroelectric Switching in Ion‐Bombarded, Defect‐Engineered BiFeO 3 Thin Films
Abstract Despite continued interest in the multiferroic BiFeO3for a diverse range of applications, use of this material is limited by its poor electrical leakage. This work demonstrates some of the most resistive BiFeO3thin films reported to date via defect engineering achieved via high‐energy ion bombardment. High leakage in as‐grown BiFeO3thin films is shown to be due to the presence of moderately shallow isolated trap states, which form during growth. Ion bombardment is shown to be an effective way to reduce this free carrier transport (by up to ≈4 orders of magnitude) by trapping the charge carriers in bombardment‐induced, deep‐lying defect complexes and clusters. The ion bombardment is also found to give rise to an increased resistance to switching as a result of an increase in defect concentration. This study demonstrates a systematic ion‐dose‐dependent increase in the coercivity, extension of the defect‐related creep regime, increase in the pinning activation energy, decrease in the switching speed, and broadening of the field distribution of switching. Ultimately, the use of such defect‐engineering routes to control materials will require identification of an optimum range of ion dosage to achieve maximum enhancement in resistivity with minimum impact on ferroelectric switching.  more » « less
Award ID(s):
1708615
PAR ID:
10047433
Author(s) / Creator(s):
 ;  ;  ;  ;  ;  ;  
Publisher / Repository:
Wiley Blackwell (John Wiley & Sons)
Date Published:
Journal Name:
Advanced Materials Interfaces
Volume:
5
Issue:
3
ISSN:
2196-7350
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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