  The fundamental electrical and thermal properties of the devices consisting
of SnxTe1-x/Sb2Te3 superlattice (SnTeSL) materials have been investigated and
compared with those of the conventional Ge2Sb2Te5 (GST225) and GeTe/Sb2Te3
superlattice (GeTeSL) in terms of their resistance switching characteristics. A
significant reduction in the switching power of SnTeSL is demonstrated by
conducting a proper initialization procedure, varying x in SnxTe1-x/Sb2Te3, and
applying short electric pulses. It is found that the observed drastic power
reduction occurs due to the exponential decrease in the electric current under
the pulse incidence. On the other hand, the thermal properties of the studied
SL materials are very similar to those of the conventional phase change
materials. The obtained transmission electron micrographs and results of
multilevel-cell recording in GeTeSL and SnTeSL via multi-pulse incidence are
totally different from the properties of the phase change materials along the
GeTe-Sb2Te3 pseudo-binary tie line. Two different models (the partial switching
and electric field-induced one) are proposed to elucidate the mechanism of the
resistance switching in the SL materials.
