Crosspoint-type variable-esistance non-volatile storage device

Abstract

Memory cells (51) are formed at each intersection between X-axis bit lines (53a and 53b) and Y-axis word lines (52a) formed in a plurality of layers. In a multi-layer crosspoint structure in which there is a plurality of vertical array surfaces sharing a word line arranged on the Y axis for every group of bit lines aligned with the Z axis, the even-numbered layer bit lines (53b) sharing a connection are connected and disconnected from a global bit line (56) by an even-numbered layer bit line-selecting switching element (1002), and the odd-numbered layer bit lines (53a) sharing a connection are connected and disconnected from the global bit line (56) by an odd-numbered layer bit line-selecting switching element (1001). The even-numbered layer bit line-selecting switching element (1002) and the odd-numbered layer bit line-selecting switching element (1001) have a bit line-selecting function and, during low-resistance writing, a current-limiting function.

Description

Technical field [0001] The present invention relates to a nonvolatile memory device having a cross-point type memory cell constructed using a so-called variable resistance element. Background technique [0002] In recent years, research and development of nonvolatile memory devices having memory cells constructed using so-called variable resistance elements have been advanced. The variable resistance element refers to an element that has a property that the resistance value changes (transitions between a high-resistance state and a low-resistance state) in response to an electrical signal, and can store information in accordance with the change in the resistance value. [0003] Also, regarding memory cells using variable resistance elements, one of them has a so-called cross point structure. In the cross point structure, each memory cell sandwiched between the bit line and the word line is formed at the position of the intersection of the bit line and the word line arranged orthog...

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Problems solved by technology

[0017] However, in the prior art described above, the resistance memory elements (resistance change elements) are arranged in the same order in the direction perpendicular to the semiconductor substrate in each layer so as to stabilize the characteristics of each layer during formation. In the case of a multi-layer cross-point type resistance change nonvolatile memory device composed of the first electrode, the resistance change layer, and the memory cell of the second electrode, it is difficult to use a unified current limiting method for each layer The problem of stabilizing the memory cell and performing the resistance change operation

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