CN-115421956-B - Method and equipment for repairing faults of internal memory

Abstract

The disclosure provides a fault repairing method and equipment for an internal memory, wherein the fault repairing method comprises the steps of determining a first fault unit of a main array in the first internal memory, determining the risk priority of the first fault unit, and repairing the first fault unit with the risk priority higher than or equal to a pre-trained priority threshold as a second fault unit. On the one hand, the number of the repaired fault units can be reduced, namely, the number of redundant units required for repairing the fault units is reduced, more redundant units remain for subsequent detection, the overall yield is improved, and the fault rate is reduced. In addition, the first fault unit with higher risk priority is repaired preferentially, so that the serious fault unit can be reduced as much as possible, the reduction of the read-write accuracy caused by the serious fault unit is relieved, the read-write accuracy is improved, the yield is further improved, and the fault rate is reduced.

Inventors

• XIONG SHIYING
• WANG XI
• WU QIXIAN
• XU JIAQI
• CAO KANYU

Assignees

• 长鑫存储技术有限公司

Dates

Publication Date

20260508

Application Date

20220905

Claims (20)

1. 1. A method of repairing a failure of an internal memory, the method comprising: determining a first failed cell of the primary array in the first internal memory; Determining a risk priority of the first faulty unit; the first fault unit with the risk priority higher than or equal to a priority threshold value obtained through pre-training is used as a second fault unit; Repairing the second fault unit; the training process of the priority threshold comprises the following steps: Initializing a current priority threshold; Determining the number of redundant units required for repairing the second internal memory according to the current priority threshold; If the absolute error between the number of the redundant units and the maximum number of the redundant units is smaller than or equal to a first preset error, determining the yield after the second internal memory is repaired under the condition that an error correction function is opened; And if the absolute error between the yield and the preset yield is smaller than or equal to a second preset error, determining the current priority threshold as a trained priority threshold.
2. 2. The method of claim 1, wherein prior to repairing the second faulty unit, further comprising: and adding the first fault unit corresponding to the target test item into the second fault unit.
3. 3. The method of claim 1, wherein prior to repairing the second faulty unit, further comprising: For at least one error correction code block, selecting a portion of the first faulty cells from among the first faulty cells included in each error correction code block, and adding the selected portion of the first faulty cells to the second faulty cells.
4. 4. The method of claim 1, wherein determining a first failed cell of the primary array in the first internal memory comprises: and under the condition that the error correction function is closed, performing fault test on the main array in the first internal memory to obtain a first fault unit.
5. 5. The method of claim 4, wherein determining the number of redundant units needed to repair the second internal memory based on the current priority threshold comprises: determining a third failed unit in the primary array of the second internal memory and a risk priority of the third failed unit; determining a third fault unit with the risk priority higher than or equal to the current priority threshold as a fourth fault unit; and determining the number of redundant units according to the number of the fourth fault units.
6. 6. The method of claim 5, wherein the determining a third failed cell in the primary array of the second internal memory comprises: And under the condition that the error correction function is closed, performing fault test on the main array of the second internal memory to obtain a third fault unit.
7. 7. The method of claim 5, wherein prior to determining the number of redundant units from the number of fourth failed units, further comprising: And adding the third fault unit corresponding to the target test item into the fourth fault unit.
8. 8. The method of claim 5, wherein prior to determining the number of redundant units from the number of fourth failed units, further comprising: For at least one error correction code block, selecting a portion of a third faulty unit from among the third faulty units included in each error correction code block, and adding the selected portion of the third faulty unit to the fourth faulty unit.
9. 9. The method according to claim 4, wherein the method further comprises: And if the absolute error between the number of the redundant units and the maximum number of the redundant units is larger than the first preset error, performing first adjustment on the current priority threshold.
10. 10. The method of claim 9, wherein the first adjusting the current priority threshold comprises: if the number of redundant units is greater than the maximum number of redundancies, increasing the current priority threshold; and if the number of the redundant units is smaller than the maximum number of the redundant units, reducing the current priority threshold.
11. 11. The method as recited in claim 1, further comprising: and if the absolute error between the yield and the preset yield is larger than the second preset error, performing second adjustment on the current priority threshold, and entering the step of determining the number of redundant units required for repairing the second internal memory according to the current priority threshold.
12. 12. The method of claim 11, wherein said second adjusting the current priority threshold comprises: if the yield is greater than the preset yield, increasing the current priority threshold; and if the yield is smaller than the preset yield, reducing the current priority threshold.
13. 13. The method of claim 1, wherein determining the post-repair yield of the second internal memory with the error correction function on comprises: Classifying the repaired second internal memory to determine the usage scenario of the second internal memory; determining target test conditions according to the use scene; And under the condition that the error correction function is opened, testing the yield of the second internal memory under the target test condition.
14. 14. The method of claim 13, wherein the method further comprises: and after the second fault unit is repaired, taking the first internal memory as the second internal memory, and entering a step of testing the yield of the second internal memory under the target test condition under the condition that the error correction function is opened.
15. 15. The method according to claim 3 or 6, wherein the fault test comprises at least one of a fault test of different test items, a fault test of different test conditions, the test conditions comprising at least one of temperature, time, voltage.
16. 16. The method of any one of claims 1 to 14, wherein the risk priority is associated with at least one of a test item corresponding to the failed unit, a test condition corresponding to the failed unit, a failure mode of the failed unit.
17. 17. A fail-over device for an internal memory, comprising: A first failure unit determining module configured to determine a first failure unit of the main array in the first internal memory; a risk priority determining module, configured to determine a risk priority of the first failure unit; The second fault unit determining module is used for taking the first fault unit with the risk priority higher than or equal to a pre-trained priority threshold value as a second fault unit; The second fault unit repairing module is used for repairing the second fault unit; the training process of the priority threshold comprises the following steps: Initializing a current priority threshold; Determining the number of redundant units required for repairing the second internal memory according to the current priority threshold; If the absolute error between the number of the redundant units and the maximum number of the redundant units is smaller than or equal to a first preset error, determining the yield after the second internal memory is repaired under the condition that an error correction function is opened; And if the absolute error between the yield and the preset yield is smaller than or equal to a second preset error, determining the current priority threshold as a trained priority threshold.
18. 18. An electronic device comprising at least one processor and a memory; The memory stores computer-executable instructions; The at least one processor executing computer-executable instructions stored in the memory causes the electronic device to implement the method of any one of claims 1 to 16.
19. 19. A computer readable storage medium having stored therein computer executable instructions which when executed by a computing device cause the computing device to implement the method of any one of claims 1 to 16.
20. 20. A computer program product for performing the method of any one of claims 1 to 16.

Description

Method and equipment for repairing faults of internal memory Technical Field The embodiment of the disclosure relates to the technical field of semiconductors, in particular to a fault repairing method and equipment for an internal memory. Background Internal memory is a core component of various computing devices, and can be divided into a variety of types, DRAM (dynamic random access memory ), nand flash memory, and the like. The internal memory may include a main array and a redundant array, each including a plurality of memory cells, the memory cells of the main array being more than the memory cells of the redundant array. When the storage units of the main array have faults, the storage units of the redundant array can be repaired. Thus, the memory cells of the main array may be referred to as main cells, and the memory cells of the redundant array may be referred to as redundant cells. In the prior art, in the production process of the internal memory, performance test is required to be performed on the internal memory so as to detect whether a main unit of the internal memory fails, and all failure units are repaired through a redundancy unit, so that the yield of the internal memory reaches the expectations, and the normal storage performance of the internal memory is ensured. However, the above approach results in a higher failure rate of the internal memory and a lower yield. Disclosure of Invention The embodiment of the disclosure provides a fault repairing method and equipment for an internal memory, so as to reduce the fault rate of the internal memory and improve the yield. In a first aspect, an embodiment of the present disclosure provides a method for repairing a failure of an internal memory, the method including: determining a first failed cell of the primary array in the first internal memory; Determining a risk priority of the first faulty unit; the first fault unit with the risk priority higher than or equal to a priority threshold value obtained through pre-training is used as a second fault unit; and repairing the second fault unit. In some embodiments, before repairing the second faulty unit, the method further includes: and adding the first fault unit corresponding to the target test item into the second fault unit. In some embodiments, before repairing the second faulty unit, the method further includes: For at least one error correction code block, selecting a portion of the first faulty cells from among the first faulty cells included in each error correction code block, and adding the selected portion of the first faulty cells to the second faulty cells. In some embodiments, the determining a first failed cell of the primary array in the first internal memory includes: and under the condition that the error correction function is closed, performing fault test on the main array in the first internal memory to obtain a first fault unit. In some embodiments, the training process of the priority threshold comprises: Initializing a current priority threshold; Determining the number of redundant units required for repairing the second internal memory according to the current priority threshold; If the absolute error between the number of the redundant units and the maximum number of the redundant units is smaller than or equal to a first preset error, determining the yield after the second internal memory is repaired under the condition that an error correction function is opened; And if the absolute error between the yield and the preset yield is smaller than or equal to a second preset error, determining the current priority threshold as a trained priority threshold. In some embodiments, the determining the number of redundant units needed to repair the second internal memory according to the current priority threshold includes: determining a third failed unit in the primary array of the second internal memory and a risk priority of the third failed unit; determining a third fault unit with the risk priority higher than or equal to the current priority threshold as a fourth fault unit; and determining the number of redundant units according to the number of the fourth fault units. In some embodiments, the determining a third failed cell in the primary array of the second internal memory includes: And under the condition that the error correction function is closed, performing fault test on the main array of the second internal memory to obtain a third fault unit. In some embodiments, before the determining the number of redundant units according to the number of the fourth faulty units, the method further includes: And adding the third fault unit corresponding to the target test item into the fourth fault unit. In some embodiments, before the determining the number of redundant units according to the number of the fourth faulty units, the method further includes: For at least one error correction code block, selecting a portion of a third faulty unit from among the third faulty uni