DETAILED ACTION
Notice of Pre-AIA or AIA Status
The present application, filed on or after March 16, 2013, is being examined under the first inventor to file provisions of the AIA .
Continued Examination Under 37 CFR 1.114
A request for continued examination under 37 CFR 1.114, including the fee set forth in 37 CFR 1.17(e), was filed in this application after final rejection. Since this application is eligible for continued examination under 37 CFR 1.114, and the fee set forth in 37 CFR 1.17(e) has been timely paid, the finality of the previous Office action has been withdrawn pursuant to 37 CFR 1.114. Applicant's submission filed on 26 May 2026 and 23 June 2026 has been entered.
CLAIM INTERPRETATION
Claims in this application are not interpreted under 35 U.S.C. §112(f).
Claim Rejections - 35 USC § 103
The following is a quotation of 35 U.S.C. 103 which forms the basis for all obviousness rejections set forth in this Office action:
A patent for a claimed invention may not be obtained, notwithstanding that the claimed invention is not identically disclosed as set forth in section 102, if the differences between the claimed invention and the prior art are such that the claimed invention as a whole would have been obvious before the effective filing date of the claimed invention to a person having ordinary skill in the art to which the claimed invention pertains. Patentability shall not be negated by the manner in which the invention was made.
Claims 1, 3-4, 8, 10-12, 16-17 and 19-20 are rejected under 35 U.S.C. 103 as being unpatentable over US Patent Application Publication No. US 2022/0004335 A1 (Khan) in view of US Patent Application Publication No. US 2018/0182465 A1 (Alhussien) in further view of US Patent Application Publication No. US 2024/0177760 A1 (Mason).
Regarding claim 1 and analogous claims 9 and 17:
Khan discloses, a system (10) comprising: a memory device (12) comprising a plurality of memory cells (a NAND array includes a plurality of cells [0001] [Fig. 1]); and a processing device (the controller (11) includes a processor), operatively coupled with the memory device, to perform operations comprising (the processor in the controller is coupled to the NAND storage media (12) and performs instructions, which may be stored on a non-transitory computer readable medium, the operations of the controller [Fig. 1] [0015] [0018-0021] [0025]) receiving a read command with respect to a set of memory cells of the plurality of memory cells of the memory device (a read command may be received by the controller (34), which is directed to memory cells of the NAND memory, such as a wordline [0019] [Fig. 4A] [0030] [0045]); configuring a plurality of groups comprising one or more single page read disturb (SPRD) groups and one or more every page read disturb (EPRD) groups (by disclosing that the controller is configured to maintain respective RD counters for each of two or more tracked units at respective granularities (32) and maintain global RD counters for each of the two or more tracked units (33) [Figs. 4A-B]. The counters correspond to wordlines, a granularity that spans multiple wordlines, and a granularity that corresponds to an entire erase block (i.e., an every page read disturb group) [Figs 4A-B]. Instead of using globally scaled thresholds, each threshold may be set independently [0037-0038]) identifying a first group, of the plurality of groups, associated with the set of memory cells, wherein each group of the plurality of groups comprises one or more wordlines of the memory device, and wherein each group of the plurality of groups has a respective read counter of a plurality of read counters and wherein each read counter of the plurality of read counters has a corresponding relocation-trigger criterion (by disclosing that for each read command, the controller may be configured to track multiple read disturb counters for a plurality of tracked unit granularities (plurality of groups) [0019]. The read disturb counters may track a single wordline (group associated with the set of memory cells, comprising one or more wordlines of the memory device), the counters may track a unit with a granularity of two or more wordlines (group associated with the set of memory cells, comprising one or more wordlines of the memory device), the counters may also track an erase block (EB) (which includes a plurality of wordlines) [0018] [0022] [Fig. 4B] [Fig. 5]. Each counter may be associated with a threshold (45) that is used to trigger data relocation (46) [Fig. 4C]) incrementing a first read counter, of the plurality of read counters, associated with the first group (a read disturb (RD) counter may be incremented that corresponds to the read request (37), which may include the WL RD counter, the selected granularity (two or more WLs) RD counter, and the EB counter [Fig. 4B] [0022] [0026] [0030]); determining whether a first value of the first read counter satisfies a first relocation-trigger criterion associated with the first read counter (by disclosing determining whether one or more of the read disturb counters (such as the WL counter, the selected granularity counter, or the EB counter) exceeds a threshold); and responsive to determining that the first value of the first read counter satisfies the first relocation-trigger criterion associated with the first read counter, performing a relocation with respect to the one or more wordlines of the first group (by teaching that in response to one or more of the RD counters exceeding a threshold (45) (72), such as the WL RD, the selected granularity RD counter, or the EB counter, a relocation of the data associated with the counter may be triggered (46) (73) [Fig. 4C] [0023] [0027] [0031] [0043] [0062] [0069] [0077] [0085] [0093]).
Khan does not explicitly disclose, but Alhussien teaches that instead of immediately triggering a relocation of the data, hitting a read disturb counter threshold should instead be a scan-trigger that triggers a data integrity scan (by teaching that performing data relocations too frequently increases write amplification and shortens the overall life of the memory due to enhanced program/erase (PE) counts. Existing methods may involve monitoring a number of reads and migrating data once the number of reads reaches a threshold – and often involve in data being relocated too frequently (causing write amplification and shorting the life of the memory). Therefore, a better method is to use an adaptive read disturb detection technique, which measures a bit error statistic (BES) using a read scrub (data integrity scan) when the read disturb count (RDC) for a particular location reaches a first selected threshold (scan-trigger criterion). Then, when the BES and RDC thresholds are both reached, data may be relocated, but if the BES is not reached, data is not relocated and the RDC value is reset to an initial value (i.e., 0) [0021-0027] [0060-0070] [Fig. 9]).
It would have been obvious for one of ordinary skill in the art before the effective filing date of the claimed invention to have modified the relocation trigger for each of the read disturb counters associated with each of the tracking units as taught by Khan to include performing relocation of the data based on reaching a read disturb counter and then performing a read scrub to determine a BES for the particular location, and only relocating data based on the read disturb counter and BES thresholds both being met, and otherwise resetting the read disturb counter if the BES does not reach the threshold and not relocating the data as taught by Khan.
One of ordinary skill in the art would have been motivated to make this modification because performing the adaptive read disturb detection in this way prevents relocation from being performed too frequently and shortening the life of the memory as taught by Alhussien in [0021-0027].
Khan in view of Alhussien does not explicitly disclose, but Mason teaches, wherein each group of the plurality of groups is configured based on a read disturb capability of each wordline in the group (by teaching that instead of relying on a uniform read disturb threshold to trigger a data validity scan, a read count threshold may be set according to the actual factors that indicate an ability tolerate the effects of read disturb, such as the amount of read window budget (RWB) and the number of program/erase (P/E) cycles of the corresponding portion of memory [see Fig. 2] [0033] [0035-0036]. These values may be updated in operation of the memory device [0060-0061]. The corresponding portion of memory may be a block, a group of wordlines, or individual wordlines [0034] [0041]).
It would have been obvious for one of ordinary skill in the art before the effective filing date of the claimed invention to have modified each grouping of word lines (individual, groups, and blocks of wordlines) with a threshold for triggering a data integrity scan as taught by Khan in view of Alhussien to include a threshold for their corresponding read counter that is based factors that indicate an actual tolerance to read disturb, such as RWB and P/E cycles, of the corresponding individual wordlines, groups of wordlines, or blocks to which the counters correspond as taught by Mason.
One of ordinary skill in the art would have been motivated to make this modification because conventionally, the threshold is set based on a worst-case scenario, which leads to scans being performed more often than necessary leading to host collisions and impacted QoS, whereas setting the threshold based on actual factors and recognizing the variabilities in manufacturing reduces unnecessary scans and reduces impacts to QoS as taught by Mason in [0014].
Regarding claim 3 and analogous claims 11 and 19:
The system of claim 1 is made obvious by Khan in view of Alhussien in further view of Mason (Khan-Alhussien-Mason).
Khan does not explicitly disclose, but Alhussien teaches wherein the respective read counter of each of the plurality of groups has a corresponding scan-window criterion, and wherein the corresponding scan-trigger criterion is associated with the corresponding scan-window criterion (by teaching that reaching the RDC threshold triggers performance of a read scrub operation to determine the BES. In this way, when the BES and RDC thresholds are both reached, data may be relocated, but if the BES is not reached, data is not relocated and the RDC value is reset to an initial value (i.e., 0), in this way, the RDC threshold trigger is an RDC scan window because every time the RDC value reaches the threshold again the read scrub is performed again and the BES is determined again, controlling the frequency of performing the read scrub (data integrity scan) (i.e., “the scan-window criterion… defines a frequency… for a round of performing a data integrity scan” as disclosed in [Applicant’s Specification, 0024]). The scan-trigger criterion is associated with the corresponding scan-window criterion because they are the same threshold (T1) [0021-0027] [0060-0070] [Fig. 9].
It would have been obvious for one of ordinary skill in the art before the effective filing date of the claimed invention to have modified the relocation trigger for each of the read disturb counters associated with each of the tracking units as taught by Khan to include performing relocation of the data based on reaching a read disturb counter and then performing a read scrub to determine a BES for the particular location, and only relocating data based on the read disturb counter and BES thresholds both being met, and otherwise resetting the read disturb counter if the BES does not reach the threshold and not relocating the data as taught by Khan.
One of ordinary skill in the art would have been motivated to make this modification because performing the adaptive read disturb detection in this way prevents relocation from being performed too frequently and shortening the life of the memory as taught by Alhussien in [0021-0027].
Regarding claim 4 and analogous claims 12 and 20:
The system of claim 3 is made obvious by Khan-Alhussien-Mason.
Khan does not explicitly disclose, but Alhussien teaches wherein the operations further comprise: determining whether the first value of the first read counter satisfies a first scan-window criterion that corresponds to the first read counter; and responsive to determining that the first value satisfies the first scan-window criterion, resetting the first value of the first read counter (by teaching that reaching the RDC threshold triggers performance of a read scrub operation to determine the BES. In this way, when the BES and RDC thresholds are both reached, data may be relocated, but if the BES is not reached, data is not relocated and the RDC value is reset to an initial value (i.e., 0) (resetting the first value of the first read counter), in this way, the RDC threshold trigger is an RDC scan window because every time the RDC value reaches the threshold again the read scrub is performed again and the BES is determined again, controlling the frequency of performing the read scrub (data integrity scan) (i.e., “the scan-window criterion… defines a frequency… for a round of performing a data integrity scan” as disclosed in [Applicant’s Specification, 0024]). The scan-trigger criterion is associated with the corresponding scan-window criterion because they are the same threshold (T1) [0021-0027] [0060-0070] [Fig. 9].
It would have been obvious for one of ordinary skill in the art before the effective filing date of the claimed invention to have modified the relocation trigger for each of the read disturb counters associated with each of the tracking units as taught by Khan to include performing relocation of the data based on reaching a read disturb counter and then performing a read scrub to determine a BES for the particular location, and only relocating data based on the read disturb counter and BES thresholds both being met, and otherwise resetting the read disturb counter if the BES does not reach the threshold and not relocating the data as taught by Khan.
One of ordinary skill in the art would have been motivated to make this modification because performing the adaptive read disturb detection in this way prevents relocation from being performed too frequently and shortening the life of the memory as taught by Alhussien in [0021-0027].
Regarding claim 8 and analogous claim 16:
The system of claim 1 is made obvious by Khan-Alhussien-Mason.
Khan further discloses, wherein the first group comprises an EPRD group of the one or more EPRD groups, and wherein the first read counter is incremented by a third preset value (by teaching the granularity of the tracked units (groups) for each wordline may include a per WL RD counter (SPRD), and a per EB RD counter (EPRD) [0022], which are analogous to Applicant’s description of the SPRD which corresponds to disturb on a single WL and EPRD which corresponds to read disturb across an entire block as disclosed in [Applicant’s Specification 0022-0023]. The EB RD counter may be incremented by one each time that it is read (a third preset value) [0026] [0030] [0042] [0048]).
Claims 2, 10 and 18 are rejected under 35 U.S.C. 103 as being unpatentable over Khan-Alhussien-Mason in further view of Chinese Patent Application Publication CN 118939187 A (Sun).
Regarding claim 2 and analogous claims 10 and 18:
The system of claim 1 is made obvious by Khan-Alhussien-Mason.
Khan-Alhussien-Mason makes obvious, and wherein the read disturb capability comprises a read disturb capability (through the analysis performed for claim 1).
Khan-Alhussien-Mason does not explicitly disclose, but Sun teaches that the read disturb capability may be a single page read disturb capability or an every page read disturb capability (by teaching that single page read disturb is when the reads are concentrated to a single page, which causes more errors than a corresponding number of reads to block read disturb, where the reads to the block are distributed evenly. In order to avoid the impact of extreme cases of SPRD, a block read limit is often set using the SPRD number as the threshold [0003]).
It would have been obvious for one of ordinary skill in the art before the effective filing date of the claimed invention to have setting the read count threshold based on the RWB and P/E counts for each grouping of individual, groups, or blocks of wordlines based on Khan-Alhussien-Mason to include using the SPRD characteristic (i.e., the minimum threshold of a wordline in each grouping) as taught by Sun rather than an BLRD (block read disturb) (EPRD) as taught by Sun.
One of ordinary skill in the art would have been motivated to make this modification because it avoids the impact of extreme cases of SPRD, and block read disturb (BLRD) causes less read disturb than SPRD for the same number of reads as taught by Sun in [0003].
Claims 5-6 and 13-14 are rejected under 35 U.S.C. 103 as being unpatentable over Khan-Alhussien-Mason in further view of US Patent Application Publication No. US 2018/0004415 A1 (Lee).
Regarding claim 5 and analogous claim 13:
The system of claim 1 is made obvious by Khan-Alhussien-Mason.
Khan further discloses, wherein the first group comprises a group of the one or more SPRD groups (by teaching the granularity of the tracked units (groups) for each wordline may include a per WL RD counter (SPRD) [0022], which is analogous to Applicant’s description of the SPRD which corresponds to disturb on a single WL as disclosed in [Applicant’s Specification 0022-0023]. Khan also teaches that different weights may be used to increment the counters based on various factors contributing to read disturb [0048]).
Khan does not explicitly disclose, but Lee teaches, and wherein the operations further comprise: determining whether the set of memory cells is associated with an edge wordline (by teaching that a controller may receive a read command and an address (S110), and may detect a read weight according to the address (S130). The read count for the specific address may then be incremented by the detected weight. The detected weight is based on the address and may be higher for addresses that correspond to memory cells that are closer to the substrate than others, such that addresses corresponding to wordlines farther from the substrate receive a lower weight, and addresses corresponding to wordlines closer to the substrate (edge wordlines) receive a higher weight. This is because memory cells adjacent to a substrate (edge wordlines) experience a greater electric field from the ground select transistor and therefore experience greater disturb effects, and the increased weight therefore reflects the greater read disturb at memory cells closer or adjacent to the substrate [0009] [0031] [0035] [0055] [0063]).
It would have been obvious for one of ordinary skill in the art before the effective filing date of the claimed invention to have modified the weight used to increment a read count for a counter of a wordline as taught by Khan to include using a higher weight for memory cells that are adjacent to a substrate (edge wordline) and to use a lower weight for memory cells that are farther away from the substrate as taught by Lee.
One of ordinary skill in the art would have been motivated to make this modification because it allows for the increase in the read count to be in consideration of the practical read disturbance occurring during a read operation performed on the wordline, which improves reliability and performance as thresholds are not reached too quickly, but at an appropriate time as taught by Lee in [0006] [0061] [0063].
Regarding claim 6 and analogous claim 14:
The system of claim 5 is made obvious by Khan-Alhussien-Mason in further view of Lee (Khan-Alhussien-Mason-Lee).
Khan does not explicitly disclose, but Lee teaches, wherein the operations further comprise: determining that the set of memory cells is associated with the edge wordline, and incrementing the first read counter by a first preset value (by teaching that a controller may receive a read command and an address (S110), and may detect a read weight according to the address (S130). The read count for the specific address may then be incremented by the detected weight. The detected weight is based on the address and may be higher for addresses that correspond to memory cells that are closer to the substrate than others, such that addresses corresponding to wordlines farther from the substrate receive a lower weight, and addresses corresponding to wordlines closer to the substrate (edge wordlines) receive a higher weight. This is because memory cells adjacent to a substrate (edge wordlines) experience a greater electric field from the ground select transistor and therefore experience greater disturb effects, and the increased weight therefore reflects the greater read disturb at memory cells closer or adjacent to the substrate [0009] [0031] [0035] [0055] [0063]).
It would have been obvious for one of ordinary skill in the art before the effective filing date of the claimed invention to have modified the weight used to increment a read count for a counter of a wordline as taught by Khan to include using a higher weight for memory cells that are adjacent to a substrate (edge wordline) and to use a lower weight for memory cells that are farther away from the substrate as taught by Lee.
One of ordinary skill in the art would have been motivated to make this modification because it allows for the increase in the read count to be in consideration of the practical read disturbance occurring during a read operation performed on the wordline, which improves reliability and performance as thresholds are not reached too quickly, but at an appropriate time as taught by Lee in [0006] [0061] [0063].
Claims 7 and 15 are rejected under 35 U.S.C. 103 as being unpatentable over Khan-Alhussien-Mason-Lee in further view of US Patent Application Publication No. US 2017/0286288 A1 (Higgins).
Regarding claim 7 and analogous claim 15:
The system of claim 5 is made obvious by Khan-Alhussien-Mason-Lee.
Khan does not explicitly disclose, but Lee teaches, wherein the operations further comprise: determining that the set of memory cells is not associated with an edge wordline; incrementing the first read counter of the first group by a second preset value (by teaching that a controller may receive a read command and an address (S110), and may detect a read weight according to the address (S130). The read count for the specific address may then be incremented by the detected weight. The detected weight is based on the address and may be higher for addresses that correspond to memory cells that are closer to the substrate than others, such that addresses corresponding to wordlines farther from the substrate receive a lower weight, and addresses corresponding to wordlines closer to the substrate (edge wordlines) receive a higher weight. This is because memory cells adjacent to a substrate (edge wordlines) experience a greater electric field from the ground select transistor and therefore experience greater disturb effects, and the increased weight therefore reflects the greater read disturb at memory cells closer or adjacent to the substrate [0009] [0031] [0035] [0055] [0063]).
It would have been obvious for one of ordinary skill in the art before the effective filing date of the claimed invention to have modified the weight used to increment a read count for a counter of a wordline as taught by Khan to include using a higher weight for memory cells that are adjacent to a substrate (edge wordline) and to use a lower weight for memory cells that are farther away from the substrate as taught by Lee.
One of ordinary skill in the art would have been motivated to make this modification because it allows for the increase in the read count to be in consideration of the practical read disturbance occurring during a read operation performed on the wordline, which improves reliability and performance as thresholds are not reached too quickly, but at an appropriate time as taught by Lee in [0006] [0061] [0063].
Lee does not explicitly disclose, but Higgins teaches determining a second group, of a plurality of neighboring groups, associated with the set of memory cells; and incrementing a second read counter of the second group by the second preset value (by teaching that a respective read of a memory unit will also disturb other nearby memory units, and the performance of a large number will eventually cause the number of bit errors to exceed an error correction capability. Accordingly, read disturb counts for the data of the read target as well as read disturb counts of one or more neighboring portions may be incremented each time a read operation is performed in the memory region or neighboring region of the storage medium [0086])
It would have been obvious for one of ordinary skill in the art before the effective filing date of the claimed invention to have modified the read disturb counts for wordlines and blocks as taught by Khan-Alhussien-Mason-Lee to include being incremented when there is a read to a neighboring region of the storage medium as taught by Higgins.
One of ordinary skill in the art would have been motivated to make this modification because reads to nearby regions can also cause read disturb, and tracking the read disturb counts by incrementing read disturb counts when there is a read to a neighboring region can be used with a threshold to prevent error correction capability from being exceeded as taught by Higgins in [0086].
Response to Arguments/Amendments
In response to the amendments to the claims, a new 35 USC §103 rejection has been made using Khan-Alhussien-Mason. As Applicant’s arguments do not address Mason for any of the particular limitations argued, Applicant’s arguments are moot. Accordingly, the claims are not indicated as allowable. The Examiner notes that as currently claimed, the claims only require that groups are “configured based on a read disturb capability” instead of “formed” as previously claimed. As a result, broader interpretations, such as configuring a read count threshold of a group, is now considered to fall within the broadest reasonable interpretation of the limitation. Accordingly, Applicant’s arguments directed to references not teaching “configuring wordlines into groups based on read disturb capability” or failing to disclose “forming each group of the plurality of groups based on read disturb capability” (emphasis added) appear to be directed to limitations that are outside the scope of the invention as presently claimed. Furthermore, the arguments are not persuasive in view of the new Mason references. Accordingly, the claims are not indicated as allowable.
Conclusion
The prior art made of record and not relied upon is considered pertinent to applicant's disclosure.
US Patent Application Publication No. US 2022/0129187 A1 (Miller) – teaches a wordline group counter for read operations [Fig. 2].
US Patent Application Publication No. US 2017/0075593 A1 (Kim) – teaches that a boundary wordline is given a greater weight as it experiences greater read disturb [0016-0028] ([0024] indicates different weights for the last wordline vs wordlines next to the last wordline).
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/CURTIS JAMES KORTMAN/Primary Examiner, Art Unit 2139
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