A phase-change memory device has a phase-change layer, a heater electrode
having an end held in contact with the phase-change layer, a contact plug
of different kinds of material having a first electrically conductive
material plug made of a first electrically conductive material and held
in contact with the other end of the heater electrode, and a second
electrically conductive material plug made of a second electrically
conductive material having a specific resistance smaller than the first
electrically conductive material, the first electrically conductive
material plug and the second electrically conductive material plug being
held in contact with each other through at least respective side surfaces
thereof, the heater electrode and the second electrically conductive
material plug being not in overlapping relation to each other, and an
electrically conductive layer electrically connected to the second
electrically conductive material plug.