Journal
REPORTS ON PROGRESS IN PHYSICS
Volume 82, Issue 9, Pages -Publisher
IOP PUBLISHING LTD
DOI: 10.1088/1361-6633/ab37d4
Keywords
ferroelectric; lead-free; room-temperature; tin titanate
Categories
Funding
- Engineering and Physical Sciences Research Council (EPSRC) [EP/P024637/1]
- EPSRC [EP/P024637/1] Funding Source: UKRI
Ask authors/readers for more resources
We review all the published literature and show that there is no experimental evidence for homogeneous tin titanate SnTiO3 in bulk or thin-film form. Instead a combination of unrelated artefacts are easily misinterpreted. The x-ray Bragg data are contaminated by double scattering from the Si substrate, giving a strong line at the 2 theta angle exactly where perovskite SnTiO3 should appear. The strong dielectric divergence near 560K is irreversible and arises from oxygen site detrapping, accompanied by Warburg/Randles interfacial anomalies. The small (4 mu C cm(-2)) apparent ferroelectric hysteresis remains in samples shown to be pure (Sn,Ti)O-2 rutile/cassiterite, in which ferroelectricity is forbidden. Only very recent work reveals real bulk SnTiO3, but it possesses an ilmenite-like structure with an elaborate array of stacking faults, not suitable for ferroelectric devices. Unpublished TEM data reveal an inhomogeneous SnO layered structured thin films, related to shell-core structures. The harsh conclusion is that there is a combination of unrelated artefacts masquerading as ferroelectricity in powders and ALD films; and only a trace of a second phase in PLD film data suggests any perovskite content at all. The fact that x-ray, dielectric, and hysteresis data all lead to the wrong conclusion is instructive and reminds us of earlier work on copper calcium titanate (a well-known boundary-layer capacitor).
Authors
I am an author on this paper
Click your name to claim this paper and add it to your profile.
Reviews
Recommended
No Data Available