Methods of forming a phase change layer and methods of fabricating a phase change memory device including the same

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

• forming a contact region in a substrate;
• forming an insulation layer on the substrate, the insulation layer including an opening exposing the contact region;
• forming a lower electrode in the opening;
• forming an insulation structure on the insulation layer, the insulation structure including a high aspect ratio structure exposing the lower electrode;
• forming at least one phase change material layer on the insulation structure to fill the high aspect ratio structure by depositing at least one phase change material at a temperature greater than about 60% of a melting point temperature of the at least one phase change material;
• forming at least one phase change material layer pattern in the high aspect ratio structure by partially removing the at least one phase change material layer;
• and
• forming an upper electrode on the at least one phase change material layer pattern.