Nonvolatile memory element, nonvolatile memory apparatus, and method of manufacture thereof

A nonvolatile memory apparatus, comprising:

• a substrate;
• a plurality of first electrode wires formed in parallel with each other on the substrate;
• a plurality of second electrode wires formed above the plurality of first electrode wires so that the plurality of second electrode wires are in parallel with each other within a plane parallel to a principal surface of the substrate, and cross in three dimensions the plurality of first electrode wires;
• and
• a plurality of nonvolatile memory elements arrayed in a matrix to respectively correspond to three-dimensional cross points of the plurality of first electrode wires and the plurality of second electrode wires,
• wherein each of the plurality of nonvolatile memory elements includes:
• a lower electrode layer;
• an upper electrode layer formed above the lower electrode layer;
• and
• a metal oxide thin film layer formed between the lower electrode layer and the upper electrode layer;
• wherein the metal oxide thin film layer includes a first region whose value of resistance increases or decreases by an electric pulse that is applied between the lower electrode layer and the upper electrode layer and a second region arranged around the first region and having a larger content of oxygen than the first region;
• wherein the lower and upper electrode layers and the first region are arranged so as to overlap as viewed from a direction of a thickness of the first region;
• and
• wherein each of the plurality of first electrode wires and each of the plurality of second electrode wires in a cross region of each of three-dimensional cross points constitute the lower electrode layer and the upper electrode layer, respectively.

A method of manufacturing a nonvolatile memory element, the memory element including a lower electrode layer;

• an upper electrode layer formed above the lower electrode layer;
• and a metal oxide thin film layer formed between the lower electrode layer and the upper electrode layer, the method comprising the steps of:
• forming the metal oxide thin film layer on the lower electrode layer;
• forming the upper electrode layer on the metal oxide thin film layer;
• and
• performing at least either one of a heat treatment and a plasma treatment on the metal oxide thin film layer in an oxygen-containing atmosphere to thereby form, in the metal oxide thin film layer, a first region whose value of resistance increases or decreases by an electric pulse that is applied between the lower electrode layer and the upper electrode layer and a second region arranged around the first region and having a larger content of oxygen than the first region.

A method of manufacturing a nonvolatile memory apparatus, the memory apparatus including a substrate;

• a plurality of first electrode wires formed in parallel with each other on the substrate;
• a plurality of second electrode wires formed above the plurality of first electrode wires so that the plurality of second electrode wires are in parallel with each other within a plane parallel to a principal surface of the substrate, and cross in three dimensions the plurality of first electrode wires;
• and a plurality of nonvolatile memory elements arrayed in a matrix to respectively correspond to three-dimensional cross points of the plurality of first electrode wires and the plurality of second electrode wires, wherein each of the plurality of nonvolatile memory elements includes a lower electrode layer;
• an upper electrode layer formed above the lower electrode layer;
• and a metal oxide thin film layer formed between the lower electrode layer and the upper electrode layer, and wherein each of the plurality of first electrode wires and each of the plurality of second electrode wires in cross region of each of three-dimensional cross points constitute the lower electrode layer and the upper electrode layer, respectively, the method comprising the steps of:
• forming the plurality of first electrode wires on the substrate;
• forming the metal oxide thin film layer on the plurality of first electrode wires;
• and
• carrying out an oxygen treatment to perform at least either one of a heat treatment and a plasma treatment on the metal oxide thin film layer in an oxygen-containing atmosphere to thereby form, in the metal oxide thin film layer, a first region whose value of resistance increases or decreases by an electric pulse that is applied between the lower electrode layer and the upper electrode layer and a second region arranged around the first region and having a larger content of oxygen than the first region.