Patent ID: 8236685

Claim:
A method of manufacturing a phase change memory device comprising: forming a first metal silicide film on a surface of an active area of a silicon substrate; forming a first interlayer dielectric on the first metal silicide film; forming vertical PN diodes in the first interlayer dielectric, the vertical PN diodes in electrical contact with the active area in the first interlayer dielectric, wherein the PN diodes are used as switching elements; forming a second metal silicide film on a surface of the vertical PN diodes; forming a second interlayer dielectric on the first interlayer dielectric and on the second metal silicide film; forming heaters in contact with each of the vertical PN diodes in the second interlayer dielectric; forming stack patterns on the heater, the stack patterns comprising a phase change layer and a top electrode; forming a third interlayer dielectric on the second interlayer dielectric covering the stack patterns; etching selectively the third interlayer dielectric to form first contact holes that expose a surface of the first metal silicide film at each of both sides of the active area; forming first word line contacts by filling the first contact hole with a conductive material; forming a fourth interlayer dielectric on the third interlayer dielectric and on the first word line contacts; forming second word line contacts that electrically contact with the first word line contacts and forming top electrode contacts into the fourth interlayer dielectric to electrically contact the top electrodes; forming bit lines on the top electrode contacts; forming a fifth interlayer dielectric on the fourth interlayer dielectric and on the bit lines; forming third word line contacts in the fifth interlayer dielectric to electrically contact with the second word line contacts; and forming word lines on the fifth interlayer dielectric and on the third word line contacts.