Phase change memory device having heat sinks formed under heaters and method for manufacturing the same

A method for manufacturing a phase change memory device, comprising the steps of:

• forming a first insulation layer on a silicon substrate having a cell region and a peripheral region;
• forming a plurality of first holes in the first insulation layer formed in the cell region of the silicon substrate;
• forming cell switching elements in the first holes;
• removing the first insulation layer that is formed in the peripheral region of the silicon substrate;
• sequentially forming a gate insulation layer and a first conductive layer in the peripheral region of the silicon substrate such that the gate insulation layer and the first conductive layer have the same cross-sectional height as the first insulation layer of the cell region;
• sequentially forming a second conductive layer and a hard mask layer on the first insulation layer and the cell switching elements in the cell region, and on the first conductive layer in the peripheral region;
• forming a gate in the peripheral region of the silicon substrate by etching the hard mask layer, the second conductive layer, the first conductive layer, and the gate insulation layer formed in the peripheral region;
• forming heat sinks comprising the second conductive layer, on the cell switching elements by etching the hard mask layer and the second conductive layer remaining in the cell region after forming the gate;
• forming a second insulation layer on the first insulation layer in the cell region and on the silicon substrate in the peripheral region such that the hard mask layer in the cell region and in the peripheral region is exposed;
• removing the hard mask layer exposed in the cell region to define second holes and to expose the heat sinks;
• forming spacers on sidewalls of the second holes and leaving a center portion of the second holes unfilled;
• forming heaters to fill the center portion of the second holes having the spacers formed therein;
• and
• forming stack patterns of a phase change layer and a top electrode on the second insulation layer including the heaters.