Method for repairing a neighborhood of rows in a memory array using a patch table

• US 20080288813A1
• Filed: 05/15/2007
• Published: 11/20/2008
• Est. Priority Date: 05/15/2007
• Status: Active Grant

• Current Assignee: SanDisk Technologies LLC (Western Digital Corporation)
• Original Assignee: Sandisk Technologies Incorporated (Western Digital Corporation)
• Inventors: Moore, Christopher S., Bosch, Derek J.
• Granted Patent: US 7,966,518 B2
• Time in Patent Office: Days
• US Class Current: 714/5
• CPC Class Codes: G11C 29/804 to prevent clustered faults

Abstract

A method for repairing a neighborhood of rows in a memory array using a patch table is disclosed. First data to be stored in row N in a memory array of the memory device, second data, if any, stored in row N-1 in the memory array, and third data, if any, stored in row N+1 in the memory array are stored in a temporary storage area of a memory device. The first data is written in row N, and, in response to an error, the first data, the second data, if any, and the third data, if any, are written in respective rows in a repair area in the memory device. The addresses of rows N-1, N, and N+1 are added to a table stored in the memory device to indicate which rows in the repair area should be used instead of rows N-1, N, and N+1.

Claims

1. A method for writing data in a repair area of a memory device, the method comprising:

storing, in a temporary storage area of a memory device;

(i) first data to be stored in row N in a memory array of the memory device, (ii) second data, if any, stored in row N-1 in the memory array, and (iii) third data, if any, stored in row N+1 in the memory array;

writing the first data in row N in the memory array; and

in response to an error in writing the first data in row N in the memory array;

writing the first data, the second data, if any, and the third data, if any, in respective rows in a repair area in the memory device; and

adding addresses of rows N-1, N, and N+1 to a table stored in the memory device, wherein the table indicates which rows in the repair area should be used instead of rows N-1, N, and N+1.

2. The method of claim 1, wherein the first data, the second data, if any, and the third data, if any, are written in respective rows in the repair area such that there are intervening blank rows between the respective rows.

3. The method of claim 1, wherein the addresses of rows N-1, N, and N+1 are added to the table such that there are intervening blank rows between the addresses in the table.

4. The method of claim 1 further comprising:

receiving a command to perform one of a read or a write operation to an address of one of rows N-1, N, and N+1;

comparing the address to addresses listed in the table; and

determining which address in the repair area should be used for said one of a read or a write operation instead of the address of said one of rows N-1, N, and N+1.

5. The method of claim 1, wherein third data is not stored in row N+1 in the memory array, and wherein the method further comprises:

storing, in the temporary storage area of the memory device, third data to be stored in row N+1 in the memory array; and

in response to the error in writing the first data in row N in the memory array, writing the third data in a row in the repair area in the memory device.

6. The method of claim 1, wherein a row stores two pages of data, wherein the first data comprises a first page of data, wherein row N stores a second page of data, and wherein the method further comprises:

storing, in the temporary storage area, the second page of data; and

in response to the error in writing the first data in row N in the memory array, writing the second page of data in a same repair row in the repair area as the first data.

7. The method of claim 1, wherein the temporary storage area is part of a controller in communication with the memory array.

8. The method of claim 1, wherein the memory array comprises a three-dimensional memory array comprising a plurality of memory cell layers stacked vertically above one another above a single silicon substrate.

9. A method for writing data in a repair area of a memory device, the method comprising:

receiving an address of row N in a memory array of a memory device;

determining whether the address of row N is present in a table stored in the memory device;

if the address of row N is present in the table, remapping the address to an address in a repair area of the memory device;

if the address of row N is not present in the table;

storing, in a temporary storage area of the memory device;

(i) first data to be stored in row N in the memory array (ii) second data, if any, stored in row N-1 in the memory array, and (iii) third data, if any, stored in row N+1 in the memory array;

writing the first data in row N in the memory array; and

in response to an error in writing the first data in row N in the memory array;

writing the first data, the second data, if any, and the third data, if any, in respective rows in a repair area in the memory device; and

adding addresses of rows N-1, N, and N+1 to the table, wherein the table indicates which rows in the repair area should be used instead of rows N-1, N, and N+1.

10. The method of claim 9, wherein the first data, the second data, if any, and the third data, if any, are written in respective rows in the repair area such that there are intervening blank rows between the respective rows.

11. The method of claim 9, wherein the addresses of rows N-1, N, and N+1 are added to the table such that there are intervening blank rows between the addresses in the table.

12. The method of claim 9, wherein if the address of the repair area is also present in the table, remapping the address of the repair area to a new address in the repair area.

13. The method of claim 9, wherein if there is an error in writing the data of the row to the repair area, adding an address of the row of the repair area to the table and writing the data of the row to another row in the repair area.

14. The method of claim 9 further comprising:

receiving a command to perform one of a read or a write operation to an address of one of rows N-1, N, and N+1;

comparing the address to addresses listed in the table; and

determining which address in the repair area should be used for said one of a read or a write operation instead of the address of said one of rows N-1, N, and N+1.

15. The method of claim 9, wherein third data is not stored in row N+1 in the memory array, and wherein the method further comprises:

storing, in the temporary storage area of the memory device, third data to be stored in row N+1 in the memory array; and

in response to the error in writing the first data in row N in the memory array, writing the third data in a row in the repair area in the memory device.

16. The method of claim 9, wherein a row stores two pages of data, wherein the first data comprises a first page of data, wherein row N stores a second page of data, and wherein the method further comprises:

storing, in the temporary storage area, the second page of data; and

in response to the error in writing the first data in row N in the memory array, writing the second page of data in a same repair row in the repair area as the first data.

17. The method of claim 9, wherein the temporary storage area is part of a controller in communication with the memory array.

18. The method of claim 9, wherein the memory array comprises a three-dimensional memory array comprising a plurality of memory cell layers stacked vertically above one another above a single silicon substrate.