Patent ID: 8049204

Claim:
A semiconductor memory device comprising a variable resistance element including a first electrode, a current path forming region provided in contact with the first electrode, and a second electrode provided in contact with the current path forming region, wherein the current path forming region comprises a first region made of a variable resistance material whose resistivity changes by applying voltage, the material containing a first metal element, and a second region formed by doping a second metal element to the variable resistance material such that a resistivity of the second region is higher than that of the first region and is not changed by applying a voltage used to change the resistivity of the first region; the first region is in contact with the first electrode and the second electrode, and extends from one electrode side to the other electrode side such that a current path is formed therebetween; and the second region is provided outside the first region in at least part of the current path forming region in direction extending from one electrode side to the other electrode side, wherein the variable resistance material is an oxide of Ni, and the first metal is Ni, and wherein the second region is made of an oxide of Ni containing Mn, and the second metal element is Mn.