Resistance change element and resistance change memory

A resistance change memory comprising:

• a first interconnect line extending in a first direction;
• a second interconnect line extending in a second direction that intersects the first direction;
• and
• a cell unit provided between the first interconnect line and the second inter connect line, the cell unit including a memory element in which data to be stored and a variable resistance value are associated,
• the memory element including first and second electrodes, first and second films between the first and second electrodes, a barrier film between the first film and the second film and metal impurities added in the first or second film,
• wherein the metal impurities migrate between the first and second films bi-directionally according to the direction of a first electric field generated between the first and second electrodes,
• when the metal impurities are present in the first film, the memory element exhibits a first resistance state, and
• when the metal impurities are present in the second film, the memory element exhibits a second resistance state different from the first resistance state.