Nonvolatile semiconductor memory device
First Claim
1. A nonvolatile semiconductor memory device comprising:
- an array of nonvolatile memory cells arranged in both rows and columns; and
a combination of word lines and bit lines arranged to extend in the row and column directions respectively so that they can select one of or a group of the memory cells for operation, whereinthe memory cell has a variable resistance element, in which data is stored through a change in electric resistance, connected at one end to a source of a selection transistor,the selection transistor is connected at a drain to the bit line extending commonly along the column direction and at a gate to the word line extending commonly along the row direction while the variable resistance element is connected at the other end to a source line in the memory cell array,a write operation on the memory cell can be electrically executed by a predetermined voltage applied to the selected word line to turn the selection transistor conductive and a predetermined writing voltage or current applied between the selected bit line and the selected source line, andthe reset operation on the memory cell can be electrically executed on the sector-by-sector basis, each sector including the plurality of memory cells connected to the common source line, by a predetermined voltage applied to the selected word line to turn the selection transistor conductive and a predetermined resetting voltage or current applied between the selected bit line and the selected source line.
3 Assignments
0 Petitions
Accused Products
Abstract
The present invention employs a memory cell structure in that one end of a variable resistance element (1) for storing information by change of electric resistance is connected to a source of a selection transistor (2) to form a memory cell (3) and, in a memory cell array (4), a drain of the selection transistor (2) is connected to a common bit line (BL) in a column direction, the other end of the variable resistance element (1) is connected to a source line (SL) and a gate of the selection transistor (2) is connected to a common word line (WL) in a row direction. In the memory cell structure, an operation of resetting data stored in the memory cell (3) is carried out for each of sectors including the plural memory cells (3) commonly connected to the source line (SL).
155 Citations
25 Claims
-
1. A nonvolatile semiconductor memory device comprising:
-
an array of nonvolatile memory cells arranged in both rows and columns; and
a combination of word lines and bit lines arranged to extend in the row and column directions respectively so that they can select one of or a group of the memory cells for operation, whereinthe memory cell has a variable resistance element, in which data is stored through a change in electric resistance, connected at one end to a source of a selection transistor, the selection transistor is connected at a drain to the bit line extending commonly along the column direction and at a gate to the word line extending commonly along the row direction while the variable resistance element is connected at the other end to a source line in the memory cell array, a write operation on the memory cell can be electrically executed by a predetermined voltage applied to the selected word line to turn the selection transistor conductive and a predetermined writing voltage or current applied between the selected bit line and the selected source line, and the reset operation on the memory cell can be electrically executed on the sector-by-sector basis, each sector including the plurality of memory cells connected to the common source line, by a predetermined voltage applied to the selected word line to turn the selection transistor conductive and a predetermined resetting voltage or current applied between the selected bit line and the selected source line. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25)
-
Specification