WO2000013087A1 - Verfahren zur reparatur von defekten speicherzellen eines integrierten speichers - Google Patents
Verfahren zur reparatur von defekten speicherzellen eines integrierten speichers Download PDFInfo
- Publication number
- WO2000013087A1 WO2000013087A1 PCT/DE1999/002571 DE9902571W WO0013087A1 WO 2000013087 A1 WO2000013087 A1 WO 2000013087A1 DE 9902571 W DE9902571 W DE 9902571W WO 0013087 A1 WO0013087 A1 WO 0013087A1
- Authority
- WO
- WIPO (PCT)
- Prior art keywords
- redundant
- lines
- programming
- line
- defect
- Prior art date
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Classifications
-
- G—PHYSICS
- G06—COMPUTING; CALCULATING OR COUNTING
- G06F—ELECTRIC DIGITAL DATA PROCESSING
- G06F11/00—Error detection; Error correction; Monitoring
- G06F11/07—Responding to the occurrence of a fault, e.g. fault tolerance
- G06F11/16—Error detection or correction of the data by redundancy in hardware
- G06F11/20—Error detection or correction of the data by redundancy in hardware using active fault-masking, e.g. by switching out faulty elements or by switching in spare elements
-
- G—PHYSICS
- G11—INFORMATION STORAGE
- G11C—STATIC STORES
- G11C29/00—Checking stores for correct operation ; Subsequent repair; Testing stores during standby or offline operation
- G11C29/70—Masking faults in memories by using spares or by reconfiguring
- G11C29/72—Masking faults in memories by using spares or by reconfiguring with optimized replacement algorithms
Definitions
- the invention relates to a method for repairing defective memory cells of an integrated memory.
- US Pat. No. 5,206,583 A describes an integrated circuit which has separable connections (fuses) for permanent programming of redundant elements.
- the integrated circuit furthermore has reversible programmable elements connected in parallel to the fuses in the form of latches, which are used for test purposes to reversibly program the redundant elements.
- the invention is based on the object of specifying a method for repairing defective memory cells of an integrated memory, for which the necessary hardware components require as little space as possible,
- the row line or column line concerned is replaced by programming one of the redundant lines
- this redundant line is programmed to repair a defect in another memory cell.
- the column lines can be, for example, bit lines and the row lines word lines of the integrated memory.
- the column lines can also be word lines and the row lines can be bit lines of the memory.
- the method has the advantage that (unlike US 5,410,687 A mentioned at the beginning) no error counters are necessary for each column line and row line to be checked, since the repair of a defect takes place immediately after it has been found. In order nevertheless to achieve a certain optimization of the repair to be carried out, the programming of at least one of the redundant lines is canceled, depending on the number of redundant lines which have already been programmed, so that a defect which is subsequently determined can subsequently be repaired with this redundant line.
- the reversible programming of the redundant lines can be carried out, for example, using reversibly programmable elements such as the latches described in US Pat. No. 5,206,583.
- the repair method according to the invention is characterized by an extremely low amount of hardware, so that it particularly suitable for implementing a self-test and self-repair of the integrated memory to be repaired. This means that all the components required to carry out the repair process are components of the integrated memory or are arranged with the same on the same integrated circuit.
- the method according to the invention can of course also be implemented in software or can also be carried out by an external tester of the integrated memory.
- the memory cells are checked line by line for defects and if a defect of the memory cell just checked is found, the affected column line is replaced by a redundant column line, provided that the number of programmed redundant column lines does not exceed a limit value. If the limit value is exceeded, all programming of redundant column lines that have occurred due to defects found in the affected row line is canceled and the affected row line is replaced by one of the redundant row lines.
- any defects identified are repaired perpendicular to the test direction. It is checked line by line and initially replaced column by column. Only when the number of redundant column lines already used exceeds the limit does the previous programming be at least partially canceled. However, only the programming of those redundant column lines which have been programmed due to defects recognized in the relevant row line are canceled. Since the affected row line is then replaced by a redundant row line and the programming of redundant column lines, which were carried out on the basis of row lines previously tested, is not canceled. Having redundant lines in the manner described repairs all the defects found within a single test run of the memory cells.
- the limit value for the number of redundant column lines to be programmed is changed during the check. This enables adaptation to the number of redundant column lines that have not yet been programmed.
- the memory cells are checked, starting with a start address. After all redundant lines have been programmed, the programming of one of the redundant lines is canceled if another defect is found. The memory cells are then checked again, starting with the start address. If a defect is found that is arranged in terms of address before the further defect, the cancellation of the programming of the corresponding redundant line is reversed. That is, the corresponding redundant line is programmed to replace the same normal line as before it was canceled. The three preceding method steps relating to the cancellation of the programming of another of the redundant lines are then repeated. If, after the cancellation of the programming of one of the redundant lines during the subsequent checking of the memory cells, no defect is found which is arranged in terms of address before the further defect, this is repaired with the redundant line which has been freed by the cancellation of its programming.
- This embodiment of the invention makes it possible to cancel the programming of those redundant lines which only repair defects which have already been identified and which, moreover, have already been remedied by other redundant lines. Therefore, after the programming of the redundant line concerned, these defects remain repaired.
- FIG. 1 shows a flow diagram of a first embodiment of the repair method
- FIG. 3 shows a flow chart for a second embodiment of the repair process.
- FIGS. 4 to 10 show an exemplary embodiment for carrying out the repair process shown in FIG. 3
- FIGS. 11 and 12 show an exemplary embodiment for carrying out the repair process shown in FIG. 1.
- the memory cells of the integrated memory are checked one after the other.
- the address is increased accordingly.
- a counter X is set to zero. If a defect is detected, the counter X is increased by one and the status of the counter X is compared with a limit value Y.
- the limit value Y applies to the number of the maximum permitted column lines programmed for repair in the current row line.
- the checking of the memory cells takes place row by row, while if a defect is found, the repair is carried out column by column. As long as the counter X does not exceed the limit value Y when a defect is detected, the defect is remedied by a redundant column line. However, if the counter X exceeds the limit value Y, the programming of those redundant column lines conditions that have been programmed to repair defects found in the current row line. The current row line is then repaired by a redundant row line.
- the replacing redundant row line itself is checked for errors after the replacement.
- the repair process is continued by checking the memory cell of the redundant row line that has the lowest column address.
- a repair is first carried out via the redundant column lines, as before. If their number exceeds the permissible limit, their programming is canceled and the redundant row line is replaced by another redundant row line.
- the checking of the memory cells of a programmed redundant row line can of course be omitted if the redundant lines have been checked prior to their programming and then only fault-free redundant lines are used for a repair.
- FIG. 11 shows a memory cell field of the integrated memory in the left part and an overview of the redundant lines in the right part.
- Figures 11 and 12 and 4 to 10 use essentially the same presentation, which is why this is only discussed once.
- the memory cells MC of the integrated memory are arranged in intersections of bit lines BL and word lines WL.
- the bit lines BL are numbered from 0 to 3 and the word lines WL from 0 to 4.
- Defective memory cells MC are marked by crosses.
- Memory cells MC that have already been repaired by redundant lines are marked by squares.
- a circle marks the current defect, i.e. the defect that has just been found one of the memory cells MC.
- a table is shown in the right part of FIG. 11, which contains all redundant lines of the memory available for illustration.
- the memory has two redundant word lines RWLO, RWLI and three redundant bit lines RBLO, RBL1, RBL2.
- the table indicates which of these redundant lines has already been programmed to replace one of the normal lines BL, WL.
- a zero means that the associated redundant line has not yet been programmed, and a one means that programming has already been carried out.
- the left part of FIG. 11 also shows how the defective memory cells MC have been repaired.
- the redundant bit lines RBLi programmed to replace the respective normal bit lines BL are entered to the right of the memory cell array and the redundant word lines RWLi programmed to replace the normal word lines are entered below the memory cell array.
- the memory cells MC were checked sequentially, starting with the memory cell address 0.0 (ie word line WL0 and bit line BL0), in the direction of the word lines WL.
- the memory cell 0.0 has no defect.
- the memory cell 0.1 was then checked (word line WL0, bit line BL1), a defect being found. This defect was repaired by replacing bit line 1 with the redundant bit line RBLO.
- the memory cells were then further tested, the error counter X being reset to 0 at the beginning of the next word line WL1.
- the defective memory cell 1.0 on the word line WL1 was repaired by the redundant bit line RBLI and the error counter X increased to the value 1. Since the bit line BL1 has already been replaced by the redundant bit line RBLO, the next error found is the one with the address 1,2. This is with the redundant bit line RBL2 repaired.
- the error counter X is increased to 2.
- the defect of the memory cell 1, 3 is determined next. This state is shown in Figure 11. This defect is not repaired with a redundant bit line, since the error counter X is increased to three and thus has exceeded the limit value Y, which also has the value two.
- the programming of the redundant bit lines RBLI and RBL2, which have been ascertained on account of the defects at the addresses 1, 0 and 1, 2 found in the current word line WL1, is canceled.
- the programming of the redundant bit line RBLO, which replaces the normal bit line BL1, on the other hand, is not canceled, since it was not due to a defect detected in the current word line WL1. They were programmed due to the defect with the address 0.1 found in the word line WL0.
- the normal word line WL1 is then replaced by the redundant word line RWL0.
- Figure 12 shows this state of the integrated memory.
- the limit value Y is in turn set to the value 2, since two of the redundant bit lines RBLi are again available for programming. These are the redundant bit lines RBLI and RBL2, the programming of which has just been canceled, as just described.
- the memory cells are checked continuously so that the defect with the address 3, 0 is determined next. This is in turn repaired with one of the redundant bit lines RBLi.
- the repair process is continued in an analogous manner, with the programming of some of the redundant bit lines being canceled whenever the state of the counter X exceeds the limit value Y.
- Figure 2 is an addition to the flow chart from 1 at the point labeled A and B, according to which the limit value Y is adapted, for example, when the number of redundant column lines already programmed exceeds a value Z. In this case, only a relatively small number of redundant column lines are available for programming, so that the limit value Y must be reduced to a value Y '.
- FIG. 3 shows the flow chart for a second embodiment of the repair method according to the invention.
- the integrated memory has two redundant word lines RWL0, RWL1 and two redundant bit lines RBLO, RBLI.
- Defective memory cells MC are in turn identified by crosses in the memory cell field. The circle indicates the current defect found.
- recognized defects are repaired by programming the redundant lines in the order shown in the table in the right part of the figures.
- the redundant word line RWL0 is therefore used to repair the first defect with address 0.1 (word line WL0, bit line BL1).
- a pointer P points to the redundant line to be used next in each case.
- FIG. 5 shows the integrated memory after the word line WL0 has been replaced by the redundant word line RBLO in terms of address.
- the programming of the redundant word line RWL0 is indicated by a 1 in the table.
- the pointer P points to the redundant line RWL1 to be programmed next.
- the checking of the memory cells is continued sequentially and the defect in the memory cell 1.0 is determined next. According to Figure 6 this is Defect repaired by programming the redundant word line RWLl.
- the other defects on the word line WL1 are also repaired automatically without having to be checked. It is assumed that the programmed redundant lines are error-free. This can be determined by performing a test before programming. Only the redundant lines found to be error-free are used for a repair.
- next defect found is the one with the address 3.0.
- the pointer P now points to the third redundant line RBLO, so that the current defect is replaced by the redundant bit line RBLO. This is shown in Figure 7. According to FIG. 8, the next defect with the address 3.1 is replaced by the redundant bit line RBLI.
- Pointer P advances to the next redundant line.
- the memory test is performed with the memory cells that have not yet been tested MC continues and the defect with address 4.2 is determined.
- the programming of the redundant word line RWL1, to which the pointer P points, is then undone.
- the memory cells are checked again, starting with address 0.0, the defect being determined first with address 1.2. Its address is smaller than the address 4.2 of the current defect. Therefore, the cancellation of the programming of the redundant word line RWL1 is reversed again.
- the pointer advances to the next redundant line RBLO (FIG. 10). Since the current defect with the address 4.2 is still not repaired, the programming of this redundant line RBLO is now canceled.
- the memory cells are tested again, starting with the start address 0.0. No defect is found that lies before the current defect with the address 4.2. This is because the defects with the addresses 1.0 and 3.0 have already been repaired by the redundant word lines RBLI and RWL0.
- the redundant bit line RBLO which has become free can thus be used for
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Abstract
Description
Claims
Priority Applications (4)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
DE59901516T DE59901516D1 (de) | 1998-08-26 | 1999-08-17 | Verfahren zur reparatur von defekten speicherzellen eines integrierten speichers |
EP99952423A EP1105802B1 (de) | 1998-08-26 | 1999-08-17 | Verfahren zur reparatur von defekten speicherzellen eines integrierten speichers |
JP2000568008A JP3734709B2 (ja) | 1998-08-26 | 1999-08-17 | 集積メモリの欠陥のあるメモリセルの修理用方法 |
US09/793,789 US6418069B2 (en) | 1998-08-26 | 2001-02-26 | Method of repairing defective memory cells of an integrated memory |
Applications Claiming Priority (2)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
DE19838861A DE19838861A1 (de) | 1998-08-26 | 1998-08-26 | Verfahren zur Reparatur von defekten Speicherzellen eines integrierten Speichers |
DE19838861.6 | 1998-08-26 |
Related Child Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
US09/793,789 Continuation US6418069B2 (en) | 1998-08-26 | 2001-02-26 | Method of repairing defective memory cells of an integrated memory |
Publications (1)
Publication Number | Publication Date |
---|---|
WO2000013087A1 true WO2000013087A1 (de) | 2000-03-09 |
Family
ID=7878822
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
PCT/DE1999/002571 WO2000013087A1 (de) | 1998-08-26 | 1999-08-17 | Verfahren zur reparatur von defekten speicherzellen eines integrierten speichers |
Country Status (7)
Country | Link |
---|---|
US (1) | US6418069B2 (de) |
EP (1) | EP1105802B1 (de) |
JP (1) | JP3734709B2 (de) |
KR (1) | KR100404016B1 (de) |
DE (2) | DE19838861A1 (de) |
TW (1) | TW440855B (de) |
WO (1) | WO2000013087A1 (de) |
Families Citing this family (18)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
DE19901206C2 (de) | 1999-01-14 | 2003-02-06 | Infineon Technologies Ag | Verfahren zur Reparatur von defekten Speicherzellen eines integrierten Halbleiterspeichers |
US20020133769A1 (en) * | 2001-03-15 | 2002-09-19 | Cowles Timothy B. | Circuit and method for test and repair |
US6904552B2 (en) * | 2001-03-15 | 2005-06-07 | Micron Technolgy, Inc. | Circuit and method for test and repair |
JP2002343098A (ja) * | 2001-05-18 | 2002-11-29 | Mitsubishi Electric Corp | 半導体記憶装置の試験方法 |
US6968479B2 (en) * | 2002-03-06 | 2005-11-22 | Hewlett-Packard Development Company, L.P. | Verifying data in a data storage device |
US7509543B2 (en) * | 2003-06-17 | 2009-03-24 | Micron Technology, Inc. | Circuit and method for error test, recordation, and repair |
JP2006185569A (ja) * | 2004-12-01 | 2006-07-13 | Toshiba Corp | 半導体記憶装置 |
JP2006228330A (ja) * | 2005-02-17 | 2006-08-31 | Toshiba Corp | 半導体記憶装置 |
US7260004B2 (en) * | 2006-01-12 | 2007-08-21 | International Busniess Machines Corporation | Method and apparatus for increasing yield in a memory circuit |
KR101314037B1 (ko) * | 2007-04-26 | 2013-10-01 | 에이저 시스템즈 엘엘시 | 메모리 복구 회로, 집적 회로, 자동화 테스트 설비 장치 및 불량 복구 시스템 |
JP4877396B2 (ja) * | 2010-01-20 | 2012-02-15 | 日本電気株式会社 | メモリ障害処理システム、および、メモリ障害処理方法 |
US11133042B2 (en) | 2016-06-27 | 2021-09-28 | SK Hynix Inc. | Semiconductor memory system and semiconductor memory device, which can be remotely initialized |
US10181346B2 (en) | 2016-08-02 | 2019-01-15 | SK Hynix Inc. | Semiconductor devices and operations thereof |
KR102592359B1 (ko) | 2016-06-27 | 2023-10-20 | 에스케이하이닉스 주식회사 | 반도체장치 |
US11217286B2 (en) | 2016-06-27 | 2022-01-04 | SK Hynix Inc. | Semiconductor memory device with power down operation |
US10037788B2 (en) * | 2016-08-02 | 2018-07-31 | SK Hynix Inc. | Semiconductor devices and semiconductor systems |
US10157097B2 (en) * | 2016-08-11 | 2018-12-18 | SK Hynix Inc. | Redundant bytes utilization in error correction code |
US11682471B2 (en) | 2020-05-28 | 2023-06-20 | International Business Machines Corporation | Dual damascene crossbar array for disabling a defective resistive switching device in the array |
Citations (3)
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EP0140595A2 (de) * | 1983-10-06 | 1985-05-08 | Eaton Corporation | Hochgeschwindigkeitsredundanzprozessor |
FR2699301A1 (fr) * | 1992-12-16 | 1994-06-17 | Sgs Thomson Microelectronics | Procédé de traitement d'éléments défectueux dans une mémoire. |
DE19736250A1 (de) * | 1996-08-20 | 1998-02-26 | Advantest Corp | Fehlerreparaturverfahren für ein Speicherbauelement |
Family Cites Families (5)
Publication number | Priority date | Publication date | Assignee | Title |
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JP2842923B2 (ja) * | 1990-03-19 | 1999-01-06 | 株式会社アドバンテスト | 半導体メモリ試験装置 |
US5206583A (en) * | 1991-08-20 | 1993-04-27 | International Business Machines Corporation | Latch assisted fuse testing for customized integrated circuits |
US6026505A (en) * | 1991-10-16 | 2000-02-15 | International Business Machines Corporation | Method and apparatus for real time two dimensional redundancy allocation |
JP3774500B2 (ja) * | 1995-05-12 | 2006-05-17 | 株式会社ルネサステクノロジ | 半導体記憶装置 |
DE19725581C2 (de) | 1997-06-17 | 2000-06-08 | Siemens Ag | Verfahren zur Funktionsüberprüfung von Speicherzellen eines integrierten Speichers |
-
1998
- 1998-08-26 DE DE19838861A patent/DE19838861A1/de not_active Withdrawn
-
1999
- 1999-08-17 WO PCT/DE1999/002571 patent/WO2000013087A1/de active IP Right Grant
- 1999-08-17 DE DE59901516T patent/DE59901516D1/de not_active Expired - Lifetime
- 1999-08-17 JP JP2000568008A patent/JP3734709B2/ja not_active Expired - Fee Related
- 1999-08-17 EP EP99952423A patent/EP1105802B1/de not_active Expired - Lifetime
- 1999-08-17 KR KR10-2001-7002435A patent/KR100404016B1/ko not_active IP Right Cessation
- 1999-08-19 TW TW088114175A patent/TW440855B/zh not_active IP Right Cessation
-
2001
- 2001-02-26 US US09/793,789 patent/US6418069B2/en not_active Expired - Lifetime
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EP0140595A2 (de) * | 1983-10-06 | 1985-05-08 | Eaton Corporation | Hochgeschwindigkeitsredundanzprozessor |
FR2699301A1 (fr) * | 1992-12-16 | 1994-06-17 | Sgs Thomson Microelectronics | Procédé de traitement d'éléments défectueux dans une mémoire. |
DE19736250A1 (de) * | 1996-08-20 | 1998-02-26 | Advantest Corp | Fehlerreparaturverfahren für ein Speicherbauelement |
Non-Patent Citations (2)
Title |
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BOSSE G P: "HIGH SPEED REDUNDANCY PROCESSOR", PROCEEDINGS OF THE INTERNATIONAL TEST CONFERENCE,US,SILVER SPRING, IEEE COMP. SOC. PRESS, vol. SYMP. 1984, 1984, pages 282 - 286, XP000746695 * |
DAY J R: "A FAULT-DRIVEN, COMPREHENSIVE REDUNDANCY ALGORITHM", IEEE DESIGN & TEST OF COMPUTERS,US,IEEE COMPUTERS SOCIETY. LOS ALAMITOS, vol. 2, no. 3, 1 June 1985 (1985-06-01), pages 35 - 44, XP000744056, ISSN: 0740-7475 * |
Also Published As
Publication number | Publication date |
---|---|
JP3734709B2 (ja) | 2006-01-11 |
US20010017806A1 (en) | 2001-08-30 |
KR100404016B1 (ko) | 2003-11-05 |
JP2002523856A (ja) | 2002-07-30 |
EP1105802A1 (de) | 2001-06-13 |
US6418069B2 (en) | 2002-07-09 |
DE19838861A1 (de) | 2000-03-02 |
DE59901516D1 (de) | 2002-06-27 |
EP1105802B1 (de) | 2002-05-22 |
KR20010072986A (ko) | 2001-07-31 |
TW440855B (en) | 2001-06-16 |
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