Phase change memory device using carbon nanotube

Abstract

Provided are a phase change memory device that can operate at low power and improve the scale of integration by reducing a contact area between a phase change material and a bottom electrode, and a method for fabricating the same. The phase change memory comprises a current source electrode, a phase change material layer, a plurality of carbon nanotube electrodes, and an insulation layer. The current source electrode supplies external current to a target. The phase change material layer is disposed to face the current source electrode in side direction. The carbon nanotube electrodes are disposed between the current source electrode and the phase change material layer. The insulation layer is formed outside the carbon nanotube electrodes and functions to reduce the loss of heat generated at the carbon nanotube electrodes.

1 . A phase change memory device using carbon nanotubes comprising:
 a current source electrode supplying external current to a target;   a phase change material layer disposed to face the current source electrode in side direction;   a plurality of carbon nanotube electrodes disposed between the current source electrode and the phase change material layer; and   an insulation layer formed outside the carbon nanotube electrodes.   
     
     
         2 . The phase change memory device of  claim 1 , wherein each of the carbon nanotube electrodes has a diameter ranging from approximately 1 nm to 100 nm. 
     
     
         3 . The phase change memory device of  claim 1 , wherein the carbon nanotube electrodes are formed in a single wall type. 
     
     
         4 . A phase change memory device using carbon nanotubes comprising:
 a current source electrode supplying external current to a target;   a phase change material layer disposed to face the current source electrode in side direction;   a plurality of carbon nanotube electrodes disposed between the current source electrode and the phase change material layer, one portion of the carbon nanotube electrodes extending to overlap with the phase change material layer; and   an insulation layer formed outside the carbon nanotube electrodes.   
     
     
         5 . The phase change memory device of  claim 4 , wherein each of the carbon nanotube electrodes has a diameter ranging from approximately 1 nm to 100 nm. 
     
     
         6 . The phase change memory device of  claim 4 , wherein the carbon nanotube electrodes have an overlapping length with the phase change material layer in a range of approximately 1/10 to 8/10 of the total length of the carbon nanotube electrodes. 
     
     
         7 . The phase change memory device of  claim 4 , wherein the carbon nanotube electrodes are formed in a single wall type. 
     
     
         8 . A phase change memory device using carbon nanotubes comprising:
 a current source electrode supplying external current to a target;   a phase change material layer disposed to face the current source electrode in side direction;   a plurality of carbon nanotube electrodes disposed between the current source electrode and the phase change material layer;   an insulation layer formed outside the carbon nanotube electrodes; and   a heat generating resistance layer disposed between the carbon nanotube electrodes and the phase change material layer in contact with the carbon nanotube electrodes.   
     
     
         9 . The phase change memory device of  claim 8 , wherein each of the carbon nanotube electrodes has a diameter ranging from approximately 1 nm to 100 nm. 
     
     
         10 . The phase change memory device of  claim 8 , wherein the carbon nanotube electrodes are formed in a single wall type.