A phase change memory cell includes first and second electrodes
electrically coupled by a phase change element. At least a section of the
phase change element comprises a higher reset transition temperature
portion and a lower reset transition temperature portion. The lower reset
transition temperature portion comprises a phase change region which can
be transitioned, by the passage of electrical current therethrough, from
generally crystalline to generally amorphous states at a lower
temperature than the higher reset transition temperature portion. The
phase change element may comprise an outer, generally tubular, higher
reset transition temperature portion surrounding an inner, lower reset
transition temperature portion.