Cross-point magnetoresistive memory array containing carbon-based layer and method of making the same

A device structure, comprising:

• first electrically conductive lines that are laterally spaced apart from each other;
• second electrically conductive lines that are vertically spaced apart from the first electrically conductive lines and are laterally spaced apart from each other;
• a two-dimensional array of magnetoresistive random access memory (MRAM) pillars located between the first electrically conductive lines and the second electrically conductive lines, wherein each of the MRAM pillars comprises a respective reference layer, a respective nonmagnetic tunnel barrier layer, and a respective free layer;
• a two-dimensional array of carbon-based layers contacting surfaces of the first electrically conductive lines and surfaces of the two-dimensional array of MRAM pillars;
• and
• a two-dimensional array of metal oxide spacers laterally surrounding the two-dimensional array of MRAM pillars,
• wherein at least one carbon-based layer within the two-dimensional array of carbon-based layers has a respective sidewall that is laterally recessed inward from a bottom periphery of an outer sidewall of a respective overlying metal oxide spacer within the two-dimensional array of metal oxide spacers.

A device structure, comprising:

• first electrically conductive lines that are laterally spaced apart from each other;
• second electrically conductive lines that are vertically spaced apart from the first electrically conductive lines and are laterally spaced apart from each other;
• a two-dimensional array of magnetoresistive random access memory (MRAM) pillars located between the first electrically conductive lines and the second electrically conductive lines, wherein each of the MRAM pillars comprises a respective reference layer, a respective nonmagnetic tunnel barrier layer, and a respective free layer;
• a two-dimensional array of carbon-based layers contacting surfaces of the first electrically conductive lines and surfaces of the two-dimensional array of MRAM pillars;
• and
• a two-dimensional array of metal oxide spacers laterally surrounding the two-dimensional array of MRAM pillars, wherein the two-dimensional array of metal oxide spacers comprises oxide of metallic elements within metallic materials of the two-dimensional array of MRAM pillars, and has an inhomogeneous compositional profile along a vertical direction.

A device structure, comprising:

• first electrically conductive lines that are laterally spaced apart from each other;
• second electrically conductive lines that are vertically spaced apart from the first electrically conductive lines and are laterally spaced apart from each other;
• a two-dimensional array of magnetoresistive random access memory (MRAM) pillars located between the first electrically conductive lines and the second electrically conductive lines, wherein each of the MRAM pillars comprises a respective reference layer, a respective nonmagnetic tunnel barrier layer, and a respective free layer;
• a two-dimensional array of carbon-based layers contacting surfaces of the first electrically conductive lines and surfaces of the two-dimensional array of MRAM pillars;
• and
• a two-dimensional array of metal oxide spacers laterally surrounding the two-dimensional array of MRAM pillars, wherein the two-dimensional array of metal oxide spacers does not contact the two-dimensional array of carbon-based layers.