Nonvolatile semiconductor memory having a word line bent towards a select gate line side

摘要

A nonvolatile semiconductor memory includes a cell unit having a select gate transistor and a memory cell connected in series, a select gate line connected to the select gate transistor, and a word line connected to the memory cell. One end of the word line is bent to the select gate line side, and a fringe is connected between a bent point and a distal end of the word line.

主权项

1. A nonvolatile semiconductor memory comprising:
cell units each having a first select gate transistor, a second select gate transistor, memory cells connected in series in a first direction and provided between the first and second select gate transistors; and first and second blocks, each comprising the cell units arranged in a second direction which crosses the first direction and having a first select gate line extending in the second direction and connected to the first select gate transistors, a second select gate line extending in the second direction and connected to the second select gate transistors, and word lines extending in the second direction, respectively connected to the memory cells; wherein the first select gate line in the first block and the first select gate line in the second block are adjacent to each other, on a first side of the blocks, word lines in the first block extend in the second direction and respectively have distal ends, at least one of the word lines in the first block at a first select gate line side is bent toward the first select gate line side and is connected to a contact plug, at least one of the word lines in the first block at a second select gate line side is bent toward the second select gate line side, on a second side of the blocks opposite to the first side, word lines in the first block extend in the second direction and respectively have distal ends, the at least one of the word lines in the first block at the first select gate line side extends in the second direction and is not connected to a contact plug, on the second side of the blocks, word lines in the second block extend in the second direction and respectively have distal ends, at least one of the word lines in the second block at a second select gate line side is bent toward the second select gate line side and is connected to a contact plug, at least one of the word lines in the second block at a first select gate line side is bent toward the first select gate line side, and on the first side of the blocks, word lines in the second block extend in the second direction and respectively have distal ends, the at least one of the word lines in the second block at the second select gate line side extends in the second direction and is not connected to a contact plug.