In an embodiment, a phase change non-volatile memory includes a number of
memory cells. The memory cells include a phase change material which may
transition between two memory states. The phase change material has
different electrical properties in different states. The memory cells may
be electrically addressable and include a transistor in each cell to
electrically read and write data to the cell. An energy beam may be used
to pre-program the device by heating selected memory cells, and
consequently changing the state of the phase change material.