Non-volatile semiconductor storage device and method of manufacturing the same

Abstract

A non-volatile semiconductor storage device includes memory cells, each of which is arranged at an intersection between a first wiring and a second wiring intersecting each other. Each of the memory cells includes: a first electrode layer; a plurality of variable resistance layers laminated on the first electrode layer and functioning as variable resistance elements; a second electrode layer formed between the variable resistance layers; and a third electrode layer formed on the top one of the variable resistance layers. Each of the variable resistance layers is composed of a material containing carbon.

1 . A non-volatile semiconductor storage device comprising memory cells, each arranged at an intersection between a first wiring and a second wiring intersecting each other,
 each of the memory cells comprising:
 a first electrode layer; 
 a plurality of variable resistance layers laminated over the first electrode layer and functioning as variable resistance elements; 
 a second electrode layer formed between the variable resistance layers; and 
 a third electrode layer formed over the top one of the variable resistance layers, 
   each of the variable resistance layers being composed of a material containing carbon.   
   
   
       2 . The non-volatile semiconductor storage device according to  claim 1 , wherein
 each of the variable resistance layers has such a low-resistance state in which high voltage need not be applied to form a filament path.   
   
   
       3 . The non-volatile semiconductor storage device according to  claim 1 , wherein
 each of the variable resistance layers has a hydrogen concentration of not more than 20%.   
   
   
       4 . The non-volatile semiconductor storage device according to  claim 1 , wherein
 each of the variable resistance layers is composed of a mixture of a graphite component with a minute crystal structure and carbon with a coarse crystal structure.   
   
   
       5 . The non-volatile semiconductor storage device according to  claim 1 , wherein
 each of the variable resistance layers is composed in part or entirely of a carbon nanomaterial.   
   
   
       6 . The non-volatile semiconductor storage device according to  claim 1 , wherein
 the second electrode layer is composed of a layer containing carbon and nitrogen.   
   
   
       7 . The non-volatile semiconductor storage device according to  claim 1 , wherein
 the first electrode layer and the third electrode layer are composed of any of metal, alloy, or metal nitride.   
   
   
       8 . The non-volatile semiconductor storage device according to  claim 1 , wherein
 each of the memory cells comprises a diode layer functioning as a diode.   
   
   
       9 . The non-volatile semiconductor storage device according to  claim 8 , wherein
 the diode layer is formed under the bottom one of the variable resistance layers.   
   
   
       10 . The non-volatile semiconductor storage device according to  claim 8 , wherein
 the diode layer is formed between the variable resistance layers.   
   
   
       11 . The non-volatile semiconductor storage device according to  claim 8 , wherein
 the diode layer is formed over the top one of the variable resistance layers.   
   
   
       12 . A method of manufacturing a non-volatile semiconductor storage device having memory cells, each memory cell arranged at an intersection between a first wiring and a second wiring intersecting each other, the method comprising:
 depositing a first electrode layer;   laminating, over the first electrode layer, a plurality of variable resistance layers functioning as variable resistance elements, and a second electrode layer so as to be sandwiched between the variable resistance layers above and below;   depositing a third electrode layer over the top one of the variable resistance layers; and   composing each of the variable resistance layers of a material containing carbon.   
   
   
       13 . The method of manufacturing the non-volatile semiconductor storage device according to  claim 12 , wherein
 each of the variable resistance layers is configured to have such a low-resistance state in which high voltage need not be applied to form a filament path.   
   
   
       14 . The method of manufacturing the non-volatile semiconductor storage device according to  claim 12 , wherein
 each of the variable resistance layers is configured to have a hydrogen concentration of not more than 20%.   
   
   
       15 . The method of manufacturing the non-volatile semiconductor storage device according to  claim 12 , wherein
 each of the variable resistance layers is composed of a mixture of a graphite component with a minute crystal structure and carbon with a coarse crystal structure.   
   
   
       16 . The method of manufacturing the non-volatile semiconductor storage device according to  claim 12 , wherein
 each of the variable resistance layers is composed in part or entirely of a carbon nanomaterial.   
   
   
       17 . The method of manufacturing the non-volatile semiconductor storage device according to  claim 12 , wherein
 the second electrode layer is composed of a layer containing carbon and nitrogen.   
   
   
       18 . The method of manufacturing the non-volatile semiconductor storage device according to  claim 12 , wherein
 the first electrode layer and the third electrode layer are composed of any of metal, alloy, or metal nitride.   
   
   
       19 . The method of manufacturing the non-volatile semiconductor storage device according to  claim 12 , wherein
 each of the variable resistance layers is deposited at temperatures around 500 degrees Celsius.   
   
   
       20 . The method of manufacturing the non-volatile semiconductor storage device according to  claim 12 , wherein
 each of the variable resistance layers is subjected to thermal treatment at temperatures around 500 degrees Celsius.