Patent ID: 7785923

Claim:
A method for manufacturing a phase change memory device having a substrate with a phase change cell region, the method comprising the steps of: forming a plurality of switching elements in the phase change cell region of a substrate; forming a first contact plug on the substrate in a region outside the phase change cell region of the substrate; forming a plurality of stack patterns each comprising a phase change layer and a top electrode formed on any one of the switching elements; forming a plurality of first top electrode contacts each being formed on any one of the top electrodes; forming a second contact plug on the first contact plug; forming a plurality of second top electrode contacts each being formed on any one of the first top electrode contacts such that stack patterns of the first top electrode contacts and the second top electrode contacts are formed; forming a third contact plug on the second contact plug; forming a plurality of bit lines each being formed on any one of the second top electrode contacts and each being electrically connected to any one of the top electrodes by any one of the stack patterns of the first top electrode contacts and the second top electrode contacts; forming a fourth contact plug on the third contact plug; and forming a word line to be electrically connected to the fourth contact plug.