  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 uC/cm2) apparent ferroelectric hysteresis remains in samples shown
in pure (Sn,Ti)O2 rutile/cassiterite, in which ferroelectricity is forbidden.
Only very recent German work reveals real bulk SnTiO3, but this is completely
inhomogeneous, consisting of 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 Unpublished TEM data reveal an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 Cambridge PLD 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).
