Method for manufacturing nonvolatile storage device

A method for manufacturing a nonvolatile storage device including:

• a plurality of first electrodes aligning in a first direction;
• a plurality of second electrodes aligning in a second direction nonparallel to the first direction and provided above the first electrodes;
• and a first storage unit provided between the first electrode and the second electrode and including a first storage layer, a resistance of the first storage layer changing by at least one of an applied electric field and an applied current, the method comprising:
• stacking a first electrode film forming a first electrode and a first storage unit film forming a first storage unit on a major surface of a substrate;
• processing the first electrode film and the first storage unit film into a strip shape aligning in the first direction;
• burying a layer of a prescribed density between the processed first electrode films and between the processed first storage unit films;
• forming a second electrode film forming a second electrode on the first storage unit film and the layer of a prescribed density;
• forming a mask layer having a higher density than the layer of a prescribed density on the second electrode film;
• processing the second electrode film into a strip shape aligning in the second direction nonparallel to the first direction by using the mask layer as a mask;
• removing a portion of the first storage unit film exposed from the layer of a prescribed density by using the mask layer as a mask to process the first storage unit film into a columnar shape including a side wall along the first direction and a side wall along the second direction;
• removing the layer of a prescribed density to expose the first storage unit film having been covered with the layer of a prescribed density;
• and
• removing the exposed first storage unit film.

A method for manufacturing a nonvolatile storage device including:

• at least one first electrode aligning in a first direction;
• at least one second electrode aligning in a second direction nonparallel to the first direction;
• and
• a storage cell including a storage element and disposed between the first electrode and the second electrode where the first electrode and the second electrode intersect,
• the method comprising:
• forming a storage cell layer on a first electrode film disposed on a substrate;
• separating the storage cell layer in the second direction nonparallel to the first direction and forming a first trench running in the first direction in order to form a first electrode aligning in the first direction on the substrate;
• burying a interlayer insulating film in the first trench;
• forming a second electrode film on the storage cell layer and the interlayer insulating film;
• processing the second electrode film to form the second electrode aligning in the second direction;
• etching the interlayer insulating film and lowering an upper surface of the interlayer insulating film to a prescribed position;
• and
• forming a second trench running in the second direction in order to separate the storage cell layer in the first direction.