METHOD OF WRITING DATA TO A SEMICONDUCTOR MEMORY DEVICE

• US 20070280000A1
• Filed: 08/02/2007
• Published: 12/06/2007
• Est. Priority Date: 11/12/2004
• Status: Active Grant

• Current Assignee: Kioxia Corporation
• Original Assignee: Kabushiki Kaisha Toshiba (Toshiba Corporation)
• Inventors: Fujiu, Masaki, Sukegawa, Hiroshi, Shibata, Noboru
• Granted Patent: US 7,593,267 B2
• Time in Patent Office: Days
• US Class Current: 365/185.240
• CPC Class Codes: G11C 11/5628 Programming or writing circuits; Data input circuits
• CPC Class Codes: G11C 16/0483 comprising cells having several storage transistors connected in series
• CPC Class Codes: G11C 16/08 Address circuits; Decoders; Word-line control circuits
• CPC Class Codes: G11C 16/28 using differential sensing or reference cells, e.g. dummy cells
• CPC Class Codes: G11C 16/3459 Circuits or methods to verify correct programming of nonvolatile memory cells
• CPC Class Codes: G11C 2211/5621 Multilevel programming verification
• CPC Class Codes: G11C 2211/5642 Multilevel memory with buffers, latches, registers at input or output
• CPC Class Codes: G11C 2211/5648 Multilevel memory programming, reading or erasing operations wherein the order or sequence of the operations is relevant
• CPC Class Codes: G11C 2216/14 Circuits or methods to write a page or sector of information simultaneously into a nonvolatile memory, typically a complete row or word line in flash memory

Abstract

A method of writing data to a semiconductor memory device with memory cells, each of which stores data defined by threshold voltage thereof in a non-volatile manner, the device having first and second memory cells disposed adjacent to each other to be sequentially written in this order, the method including: performing a first data write operation for writing data defined by a threshold voltage lower than a desired threshold voltage into the first memory cell; performing a second data write operation for writing data into the second memory cell; and performing a third data writing operation for writing data defined by the desired threshold voltage into the first memory cell.

Claims

1. A method of writing data to a semiconductor memory device with memory cells, each of which stores data defined by threshold voltage thereof in a nonvolatile manner, the device having first and second memory cells disposed adjacent to each other to be sequentially written in this order, the method comprising:

performing a first data write operation for writing data defined by a threshold voltage lower than a desired threshold voltage into the first memory cell;

performing a second data write operation for writing data into the second memory cell; and

performing a third data writing operation for writing data defined by the desired threshold voltage into the first memory cell.