A phase changeable random access memory (PRAM) and methods for
manufacturing the same. An example unit cell of a non-volatile memory,
such as a PRAM, includes a MOS transistor, connected to an address line
and a data line, where the MOS transistor receives a voltage from the
data line. The unit cell further includes a phase change material for
changing phase depending on heat generated by the voltage and a top
electrode, connected to a substantially ground voltage.