Nonvolatile memory device and method for manufacturing same

1. A nonvolatile memory device comprising:

at least one first interconnection extending in a first direction;

at least one second interconnection disposed above the first interconnection and extending in a second direction nonparallel to the first direction;

a memory cell disposed between the first interconnection and the second interconnection at an intersection of the first interconnection and the second interconnection and including a memory element;

an element isolation layer disposed between the memory cells; and

at least one dielectric film with a higher density than the element isolation layer being disposed on a sidewall surface of the memory cell,

the element isolation layer including a low-k material, a dielectric constant of the element isolation layer being lower than a dielectric constant of the dielectric film, a sidewall surface and a bottom surface of the element isolation layer being covered with the continuous dielectric film.

2. The device according to claim 1 , wherein a concentration of impurities contained in the element isolation layer is higher than a concentration of impurities contained in the dielectric film.

3. The device according to claim 1 , wherein the dielectric film includes a first dielectric film and a second dielectric film, the first dielectric film with a higher density than the element isolation layer is disposed on the sidewall surface of the memory cell, and the second dielectric film with a lower dielectric constant than the first dielectric film and with a higher density than the element isolation layer is disposed on the first dielectric film.

4. The device according to claim 1 , wherein a rectifying element is provided in the memory cell.