Patent ID: 8871559

Claim:
A method for fabricating a phase change memory device, comprising: forming a plurality of bottom electrodes on a substrate, wherein the bottom electrodes are formed of a refractory metal, wherein the forming of the bottom electrodes comprises: patterning a conductive layer on a plurality of contact plugs connected to a plurality of diodes to form a spacer electrode having an L-shape or a step shape which contacts a portion of the contact plugs; and performing a trim pattern process on the spacer electrode to form the plurality of bottom electrodes having a linear plane defined on the diodes and an L-shape or a stepped shaped section connected to about half a top surface of the contact plugs; forming a first mold layer on the substrate to extend in a first direction where the bottom electrodes are exposed; forming a second mold layer on the substrate, the second mold layer extending in a second direction orthogonal to the first direction to expose parts of the bottom electrodes; forming a phase change material layer on the first and second mold layers to be connected to the parts of the bottom electrodes; dividing the phase change material layer into a plurality of phase change layers respectively connected to the parts of the bottom electrodes; and forming a plurality of top electrodes on the phase change layers.