Storage device and bad block assigning method thereof

• US 10,388,395 B2
• Filed: 12/11/2017
• Issued: 08/20/2019
• Est. Priority Date: 03/29/2017
• Status: Active Grant

• Current Assignee: Samsung Electronics Co. Ltd.
• Original Assignee: Samsung Electronics Co. Ltd.
• Inventors: Lee, Kyungduk, Shim, Young-Seop
• Primary Examiner(s): Torres, Joseph D
• Application Number:
  US15/837,841
• Publication Number:
  US 20180286492A1
• Time in Patent Office: 617 Days
• CPC Class Codes: G11C 29/38 Response verification devices
• CPC Class Codes: G11C 29/44 Indication or identification of errors, e.g. for repair
• CPC Class Codes: G11C 29/789 using non-volatile cells or latches

Abstract

A storage device includes a nonvolatile memory device that detects loop counts of state pass loops of at least one target state of a plurality of target states, and generates state loop count information (SLCI) indicative of whether a program operation is successful based on the detected loop count of the state pass loops, during a program operation of selected memory cells; and a storage controller that makes a request to the nonvolatile memory device for the state loop count information in response to detection of an operation condition or an external command, and assigns a memory block in which the selected memory cells are included as a bad block based on the state loop count information from the nonvolatile memory device.

Claims

1. A storage device comprising:

a nonvolatile memory device configured to detect loop counts of state pass loops of at least one target state of a plurality of target states, and generate state loop count information (SLCI) indicative of whether a program operation is successful based on the detected loop counts of the state pass loops, during a program operation of selected memory cells; and

a storage controller configured to make a request to the nonvolatile memory device for the state loop count information in response to detection of an operation condition or an external command, and assign a memory block in which the selected memory cells are included as a bad block based on the state loop count information from the nonvolatile memory device.

2. The storage device of claim 1, wherein the operation condition includes a condition that a number of error bits included in data read from the selected memory cells exceeds a reference value.

3. The storage device of claim 1, wherein the operation condition includes a condition that an operation temperature of the nonvolatile memory device exceeds a reference temperature.

4. The storage device of claim 1, wherein the operation condition includes a condition that a number of program/erase (P/E) cycles of the memory block exceeds a reference count.

5. The storage device of claim 1, wherein the storage controller comprises a bad block manager configured to map the memory block as the bad block based on the operation condition and the state loop count information.

6. The storage device of claim 1, wherein the nonvolatile memory device comprises:

a program loop count circuit configured to detect the loop counts of the state pass loops of the plurality of target states; and

a status register configured to store the state loop count information, which indicates a pass state or fail state of each of the plurality of target states, based on the detected loop counts of the state pass loops.

7. The storage device of claim 6, wherein the nonvolatile memory device further comprises a dedicated pin configured to output the state loop count information.

8. The storage device of claim 1, wherein the storage controller is configured to determine a fail state of the program operation of some target states of the plurality of target states based on the state loop count information, and assign the memory block as the bad block based on a result of determining the fail state.

9. The storage device of claim 1, wherein the storage controller is configured to make the request to the nonvolatile memory device for the state loop count information by using a memory block health information request command.

10. The storage device of claim 1, wherein the storage controller is configured to make the request to the nonvolatile memory device for the state loop count information through a status read command.

11. A bad block assignment method of a storage device, the storage device comprising a nonvolatile memory device and a storage controller, the method comprising:

monitoring, by the storage controller, an operation condition for performing a run time bad block processing operation;

making, by the storage controller, a request to the nonvolatile memory device for state loop count information of a selected memory block of the nonvolatile memory device based on a result of the monitoring; and

assigning, by the storage controller, the selected memory block as a bad block with reference to the state loop count information from the nonvolatile memory device,

wherein the state loop count information is information indicative of a pass state or a fail state of a program operation, and the nonvolatile memory device determines the state loop count information based on a result of detecting loop counts of state pass loops of each of a plurality of target states of memory cells of the selected memory block upon programming the selected memory block.

12. The method of claim 11, wherein the operation condition includes a condition that a specific command is received from a host.

13. The method of claim 11, wherein the operation condition includes at least one of a condition that a number of error bits detected from data stored in the selected memory block exceeds a reference value, a condition that an operation temperature of the nonvolatile memory device exceeds a reference temperature, and a condition that a number of P/E cycles of the selected memory block exceeds a reference count.

14. The method of claim 11, wherein the state loop count information is generated from the memory cells connected to a specific word line of the selected memory block or from a specific page belonging to the specific word line.

15. The method of claim 14, wherein the specific word line includes a word line that is adjacent to a ground selection line, a string selection line, or a dummy word line of the selected memory block.

16. A storage device comprising:

a nonvolatile memory device configured to store data in a plurality of memory blocks; and

a storage controller configured to detect an operation condition of the nonvolatile memory device, request state loop count information from the nonvolatile memory device based on the detected operation condition, receive the state loop count information from the nonvolatile memory device, and assign a selected memory block from among the plurality of memory blocks as a bad block based on the state loop count information,

wherein the state loop count information comprises loop counts of state pass loops of a plurality of target states of memory cells within the selected memory block.

17. The storage device of claim 16, wherein the operation condition includes a condition that a number of error bits included in data read from the memory cells exceeds a reference value.

18. The storage device of claim 16, wherein the operation condition includes a condition that an operation temperature of the nonvolatile memory device exceeds a reference temperature.

19. The storage device of claim 16, wherein the operation condition includes a condition that a number of program/erase (P/E) cycles of the selected memory block exceeds a reference count.

20. The storage device of claim 16, wherein the storage controller is configured to assign the selected memory block as the bad block based on whether the loop counts of the state pass loops of the plurality of target states are within state pass loop reference ranges.