Memory cells having a plurality of resistance variable materials

A method comprising:

• applying a first signal to an access line of an array to program a group of memory cells to respective targets data states of a plurality of data states, wherein each memory cell of the group respectively comprises:
• a plurality of storage materials each including a respective active region formed between a plug material and an electrode material, wherein at least two of the plurality of storage materials have different thicknesses, and the first signal transitions a first active region of the plurality of storage materials;
• a conductive material that contacts the electrode material and each of the plurality of storage materials;
• and
• a heater material that contacts the plug material and each of the plurality of storage materials.

A method comprising:

• programming a group of memory cells of an array to respective data states, wherein each cell of the group includes a resistance variable storage element comprising a plurality of resistance variable materials,
• wherein the plurality of resistance variable materials are formed between a plug material and an electrode material,
• wherein each cell of the group includes a conductive material that contacts the electrode material and each of the plurality of resistance variable materials, and
• wherein each cell of the group includes a heater material that contacts the plug material and each of the plurality of resistance variable materials. Amendment dated August 25, 2016

A method comprising:

• turning on a group of select devices corresponding to a respective group of memory cells of an array of memory cells, wherein each cell comprises a resistance variable storage element comprising a plurality of resistance variable materials,
• wherein the plurality of resistance variable materials are formed between a plug material and an electrode material,
• wherein each cell of the group includes a conductive material that contacts the electrode material and each of the plurality of resistance variable materials, and
• wherein each cell of the group includes a heater material that contacts the plug material and each of the plurality of resistance variable materials;
• and
• sensing a current through the respective resistance variable storage elements of the group of memory cells to determine a respective resistance level of the cells.