NONVOLATILE MEMORY DEVICE AND RELATED METHOD OF OPERATION

• US 20130286747A1
• Filed: 02/07/2013
• Published: 10/31/2013
• Est. Priority Date: 04/26/2012
• Status: Active Grant

• Current Assignee: Samsung Electronics Co. Ltd.
• Original Assignee: Samsung Electronics Co. Ltd.
• Inventors: Kwak, Donghun
• Granted Patent: US 8,942,046 B2
• Time in Patent Office: Days
• US Class Current: 365/185.22
• CPC Class Codes: G11C 11/5628 Programming or writing circuits; Data input circuits
• CPC Class Codes: G11C 11/5642 Sensing or reading circuits; Data output circuits
• CPC Class Codes: G11C 16/0483 comprising cells having several storage transistors connected in series
• CPC Class Codes: G11C 16/10 Programming or data input circuits
• CPC Class Codes: G11C 16/34 Determination of programming status, e.g. threshold voltage, overprogramming or underprogramming, retention
• CPC Class Codes: G11C 16/3427 Circuits or methods to prevent or reduce disturbance of the state of a memory cell when neighbouring cells are read or written
• CPC Class Codes: G11C 2211/5621 Multilevel programming verification
• CPC Class Codes: H10B 41/27 the channels comprising vertical portions, e.g. U-shaped channels
• CPC Class Codes: H10B 43/27 the channels comprising vertical portions, e.g. U-shaped channels
• CPC Class Codes: H10B 69/00 Erasable-and-programmable ROM [EPROM] devices not provided for in groups H10B41/00 - H10B63/00, e.g. ultraviolet erasable-and-programmable ROM [UVEPROM] devices

Abstract

A nonvolatile memory device comprises cell strings formed in a direction substantially perpendicular to a substrate and is configured to select memory cells in units corresponding to a string selection line. The device selects a page to be programmed among pages sharing a common word line, determines a level of a program voltage to be provided to the selected page according to a location of a string selection line corresponding to the selected page, and writes data in the selected page using the determined level of the program voltage.

Claims

1. A method of operating a nonvolatile memory device comprising cell strings formed in a direction substantially perpendicular to a substrate and configured to select memory cells in units corresponding to a string selection line, the method comprising:

selecting a page to be programmed among pages sharing a common word line;

determining a level of a program voltage to be provided to the selected page according to a location of a string selection line corresponding to the selected page; and

writing data in the selected page using the determined level of the program voltage.

2. The method of claim 1, wherein determining the level of the program voltage to be provided to the selected page comprises:

comparing the location of the string selection line of the selected page with a location of a reference string selection line; and

determining a level of the program voltage to be provided to the selected page by determining whether the selected page is programmed in a first part of a reference order.

3. The method of claim 2, wherein determining whether the selected page is programmed in the first part of the reference order comprises determining whether the location of the string selection line of the selected page precedes the location of the reference string selection line.

4. The method of claim 3, wherein where the selected page is programmed in the first part of the reference order, an increment of a program voltage to be provided to a word line corresponding to the selected page is set to be lower than an increment of a predetermined program voltage.

5. The method of claim 4, wherein where the selected page is programmed in the first part of the reference order, a level of a pass voltage to be provided to an unselected word line is set to be lower than a level of a predetermined pass voltage.

6. The method of claim 4, wherein where the selected page is programmed in the first part of the reference order, a level of a start program voltage among program voltages to be provided to the selected word line is set to be higher than a level of a predetermined start program voltage.

7. The method of claim 3, wherein where the selected page is programmed after the first part of the reference order, a level of a verification read voltage to be provided to the selected word line is set to be higher than a level of a predetermined verification read voltage.

8. A nonvolatile memory device, comprising:

a memory cell array comprising a plurality of pages corresponding to different string selection lines and sharing a common word line;

a voltage generator configured to generate voltages to be provided to the memory cell array; and

control logic configured to control the memory cell array and the voltage generator,

wherein the control logic determines a program order of a selected page among the plurality of pages according to a location of a string selection line corresponding to the selected page and determines a level of a voltage to be provided to the selected page according to a program order of the selected page.

9. The nonvolatile memory device of claim 8, wherein the memory cell array comprises:

a first page selected by a first string selection line; and

a second page selected by a second string selection line different from the first string selection line and sharing a common word line with the first page,

wherein where the first page is programmed prior to the second page, the control logic controls the voltage generator such that an increment of a program voltage to be provided to the first page is smaller than an increment of a program voltage to be provided to the second page.

10. The nonvolatile memory device of claim 9, wherein where the first page is programmed prior to the second page, the control logic controls the voltage generator such that a level of a verification read voltage to be provided to the second page is higher than that of a verification read voltage to be provided to the first page.

11. The nonvolatile memory device of claim 9, wherein where the first page is programmed prior to the second page, the control logic controls the voltage generator such that a level of a start program voltage of program voltages to be provided to the first page is set to be higher than a level of a start program voltage of program voltages to be provided to the second page.

12. The nonvolatile memory device of claim 9, wherein where the first page is programmed prior to the second page, the control logic controls the voltage generator such that a level of a pass voltage to be provided to unselected word lines at programming of the first page is set to be lower than a level of a pass voltage to be provided to unselected word lines at programming of the second page.

13. The nonvolatile memory device of claim 8, wherein in a read operation, the control logic determines a level of a read voltage to be provided to the selected page according to a programmed order of the selected page of a plurality of pages sharing the same word line.

14. The nonvolatile memory device of claim 13, wherein the memory cell array comprises:

a first page selected by a first string selection line; and

a second page selected by a second string selection line different from the first string selection line and sharing the same word line as the first page,

wherein where the first page is programmed prior to the second page, the control logic controls the voltage generator such that a level of a selection read voltage corresponding to the first page is set to be lower than a level of a selection read voltage corresponding to the second page.

15. The nonvolatile memory device of claim 14, wherein where the first page is programmed prior to the second page, the control logic controls the voltage generator such that a level of a non-selection read voltage corresponding to the first page is set to be lower than a level of a non-selection read voltage corresponding to the second page.

16. The nonvolatile memory device of claim 8, further comprising:

a decoder configured to receive the address from an external device and to provide the memory cell array with a voltage to be provided to the selected page according to a control of the control logic;

device comprising cell strings formed in a direction substantially perpendicular to a substrate

17. A method of operating a nonvolatile memory device comprising a three dimensional memory cell array comprising cell strings formed in a direction substantially perpendicular to a substrate and a plurality of pages corresponding to different string selection lines and sharing a common word line, the method comprising:

determining a program order of a selected page among the plurality of pages according to a location of a string selection line corresponding to the selected page; and

determining a level of a voltage to be provided to the selected page according to a program order of the selected page.

18. The method of claim 17, wherein the three dimensional memory cell array comprises a first page selected by a first string selection line and a second page selected by a second string selection line different from the first string selection line and sharing a common word line with the first page, the method further comprising:

determining that the first page is to be programmed prior to the second page, and consequently controlling the voltage generator such that an increment of a program voltage to be provided to the first page is smaller than an increment of a program voltage to be provided to the second page.

19. The method of claim 18, further comprising where the first page is to be programmed prior to the second page, controlling the voltage generator such that a level of a verification read voltage to be provided to the second page is higher than that of a verification read voltage to be provided to the first page.

20. The method of claim 17, wherein the nonvolatile memory device comprises a three-dimensional NAND flash memory device.