Memory Cells, Methods of Forming Memory Cells, and Methods of Programming Memory Cells

A method of forming a memory cell, comprising:

• forming a first region of a programmable material over a first access line;
• forming a second region of the programmable material over the first region;
• the first and second regions being compositionally different from one another;
• forming a second access line over the second region;
• wherein the programmable material has two distinguishable and interchangeable memory states, with one of the states being a “SET” state and the other being a “RESET” state;
• the “SET” state passing greater current between the first and second access lines than the “RESET” state when an electrical field is applied across the programmable material;
• the “SET” and “RESET” states being interchanged with one another by altering one or both of a concentration of ions and a concentration of ion vacancies in at least one of the first and second regions;
• wherein the first and second regions together comprise a pn diode in the programmable material in the “SET” state;
• and
• providing the ions and/or the ion vacancies in said at least one of the first and second regions.

A method of forming and programming a memory cell, comprising:

• forming a first region of a programmable material over and directly against a first access line;
• forming a second region of the programmable material over the first region;
• the first and second regions being compositionally different from one another;
• forming a second access line over and directly against the second region;
• wherein the programmable material has two distinguishable and interchangeable memory states, with one of the states being a “SET” state and the other being a “RESET” state;
• the “SET” state passing greater current than the “RESET” state when an electrical field is applied across the programmable material;
• the “SET” and “RESET” states being interchanged with one another by altering one or both of a concentration of ions and a concentration of ion vacancies in at least one of the first and second regions;
• wherein the first region is of a first conductivity type in the “SET” state and the second region is of a second conductivity type in the “SET” state, with the second conductivity type being opposite of the first conductivity type;
• the first and second regions together comprising a pn diode in the programmable material in the “SET” state;
• and
• altering the ion concentration and/or the ion vacancy concentration in said at least one of the first and second regions to change the programmable material from one memory state to the other.

A method of forming and programming a memory cell, comprising:

• forming a first region of a programmable material over and directly against a first access line;
• forming a second region of the programmable material over the first region;
• forming a second access line over and directly against the second region;
• wherein the programmable material has two distinguishable and interchangeable memory states, with one of the memory states being a “SET” state and the other being a “RESET” state;
• the “SET” state passing greater current than the “RESET” state when an electrical field is applied across the programmable material;
• the “SET” and “RESET” states being interchanged with one another by altering one or both of a concentration of ions and a concentration of ion vacancies in the second region to reversibly form a filament across the second region;
• wherein the first region is of a first conductivity type in the “SET” state and the filament is of a second conductivity type in the “SET” state, with the second conductivity type being opposite of the first conductivity type;
• the first and second regions together comprising a pn diode in the programmable material in the “SET” state;
• and
• altering the ion concentration and/or the ion vacancy concentration in the second region to change the programmable material from one memory state to the other.

A method of forming and programming a memory cell, comprising:

• forming a programmable material over a first access line;
• the programmable material having a first region and a second region;
• forming a second access line over the programmable material;
• wherein the programmable material has two distinguishable and interchangeable memory states, with one of the memory states being a “SET” state and the other being a “RESET” state;
• the “SET” state passing greater current than the “RESET” state when an electrical field is applied across the programmable material;
• the “SET” and “RESET” states being interchanged with one another by modifying one or both of a concentration of ions and a concentration of ion vacancies in the second region to reversibly alter the second region;
• wherein the first region is of a first conductivity type in the “SET” state and at least part of the second region is of a second conductivity type in the “SET” state, with the second conductivity type being opposite of the first conductivity type;
• the first and second regions together comprising a pn diode in the programmable material in the “SET” state;
• and
• modifying the ion concentration and/or the ion vacancy concentration in the second region to change the programmable material from one memory state to the other.