Crack propagation monitoring structure, wafer and crack propagation monitoring method

Abstract

The invention provides a crack propagation monitoring structure, a wafer and a crack propagation monitoring method, relates to the technical field of semiconductors, and can monitor growth of cracks and capture device damage caused by crack propagation of the wafer in a cutting process. And the relationship between the crack propagation and the temperature cyclic stress is given, so that subsequent reliability evaluation is facilitated. The crack propagation monitoring structure comprises a plurality of monitoring chains which are arranged along a first direction and extend along a second direction, and the first direction and the second direction are crossed; a plurality of test pieces; each monitoring chain corresponds to at least one test piece and is connected with at least one test piece; the test piece is used for determining whether the monitoring chain connected with the test piece is disconnected so as to determine the position of crack propagation.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of semiconductor technology, and in particular to a crack propagation monitoring structure, a wafer and a crack propagation monitoring method. BACKGROUND

[0002] A chip is an important device in an electronic device. In a chip manufacturing process, a wafer can be cut to manufacture the chip. Specifically, a plurality of chips are generally designed to be spaced apart on the wafer, and the plurality of chips are separated from each other by cutting from the wafer.

[0003] However, when the wafer is cut, a crack is easily formed at the cutting position, and the crack extending to a functional area of the chip can cause failure of the chip. SUMMARY

[0004] To solve the above technical problem, the present application provides a crack propagation monitoring structure, a wafer and a crack propagation monitoring method, which can monitor the growth of the crack, capture the crack propagation caused by the wafer in the cutting process, and thus cause device damage; and the relationship between the crack propagation and the temperature cycle stress is given, which is convenient for subsequent reliability evaluation.

[0005] In a first aspect, the embodiments of the present application provide a crack propagation monitoring structure, which comprises: a plurality of monitoring chains arranged along a first direction and extending along a second direction, wherein the first direction and the second direction intersect; a plurality of test pieces; each monitoring chain corresponds to at least one test piece and is connected to the at least one test piece; the test piece is used to determine whether the monitoring chain connected to the test piece is disconnected to determine the position of the crack propagation.

[0006] Since the crack propagation monitoring structure comprises a plurality of monitoring chains located at different positions, the growth of the crack can be monitored, the crack propagation caused by the wafer in the cutting process can be captured, and thus the device damage can be caused.

[0007] Exemplarily, the first direction and the second direction are perpendicular.

[0008] Exemplarily, the first direction is the width direction of the cutting lane, and the second direction is the extension direction of the cutting lane.

[0009] According to the first aspect, along the second direction, each monitoring chain comprises a plurality of monitoring units arranged at intervals; each monitoring chain further comprises a first connecting unit and a second connecting unit, and in the same monitoring chain, except for the first monitoring unit and the last monitoring unit, the other monitoring units are connected to the monitoring units located on both sides of the monitoring units through the first connecting unit and the second connecting unit.

[0010] In this way, the setting mode of the monitoring chain is more simple.

[0011] According to a first aspect, or any one of the implementations of the first aspect, the monitoring unit comprises N layers of monitoring layers arranged in a stack, two adjacent layers of the monitoring layers are connected, N is a positive integer greater than or equal to 2; the N layers of monitoring layers comprise a first monitoring layer, a jth monitoring layer, and an Nth monitoring layer, the first connecting unit is arranged in the same layer as the first monitoring layer, and the second connecting unit is arranged in the same layer as the Nth monitoring layer.

[0012] Since the interconnection medium layer comprises a plurality of medium layers, cracks can occur in any medium layer, the first connecting unit is arranged in the same layer as the first monitoring layer, and the second connecting unit is arranged in the same layer as the Nth monitoring layer, so that the presence of cracks at each position of the monitoring chain can be better monitored, and the growth of the cracks can be more accurately monitored.

[0013] According to the first aspect, or any one of the implementations of the first aspect, the crack propagation monitoring structure further comprises a plurality of connecting pieces, the connecting pieces being used to connect two adjacent monitoring chains. In this way, different monitoring chains can share the test piece, and the resistance value of each monitoring chain can be conveniently tested.

[0014] According to the first aspect, or any one of the implementations of the first aspect, in addition to the first monitoring chain and the last monitoring chain, the other monitoring chains are connected to the monitoring chains located on the two sides of the monitoring chains through two connecting pieces at the opposite ends of the monitoring chains in the second direction. That is, the shape formed by the monitoring chains can be approximately "serpentine". In this way, the growth of the cracks can be monitored in the entire monitoring chain, the range of monitoring the growth of the cracks is more extensive, and the growth of the cracks can be more accurately monitored.

[0015] According to the first aspect, or any one of the implementations of the first aspect, the connecting piece comprises at least one connecting layer, and the connecting layer and the monitoring layer are formed through the same semiconductor process. In this way, the preparation steps can be reduced, and the process is simplified.

[0016] According to the first aspect, or any one of the implementations of the first aspect, the test piece comprises N layers of test layers; the jth layer of the monitoring layer of the monitoring unit located at the end of the monitoring chain extends to the jth layer of the test layer of the test piece corresponding to the monitoring chain, so as to be connected to the test piece, where j is a positive integer less than or equal to N. The connection mode of the test piece and the monitoring chain is simple.

[0017] According to the first aspect, or any one of the implementations of the first aspect, the N layers of test layers and the N layers of monitoring layers are formed through the same semiconductor process. In this way, the preparation steps can be reduced, and the process is simplified.

[0018] According to the first aspect, or any one of the implementations of the first aspect, each monitoring chain corresponds to two test pieces, and the two test pieces are located at preset ends of the monitoring chain, the preset ends being ends of the monitoring chain not connected with a next monitoring chain; and the jth monitoring layer of the monitoring unit at the preset end extends to the jth test layer of the two test pieces respectively to connect with the two test pieces, where j is a positive integer less than or equal to N.

[0019] In this way, the two test pieces can be shared by the two adjacent monitoring chains, so that the number of test pieces is reduced, and the preparation steps are reduced and the process is simplified. In addition, since one monitoring chain can correspond to four test pieces, four-terminal detection resistance can be used to eliminate the impedance of the contact resistance between the probe and the test piece and the wiring resistance, so that the measured resistance of each monitoring chain is more accurate.

[0020] According to the first aspect, or any one of the implementations of the first aspect, the size of the monitoring chain in the first direction is W1, W1 is less than or equal to 2 μm and greater than or equal to 0.5 μm.

[0021] In this way, the size of the monitoring chain is not too small (determined by design rules) to be inconvenient for preparation, and the size of the monitoring chain is not too large to better monitor the crack propagation (for example, if the size is too large, the crack may stop at half of the monitoring chain, and the obtained resistance value may not be able to determine whether the monitoring chain is broken).

[0022] According to the first aspect, or any one of the implementations of the first aspect, the spacing between the two adjacent monitoring chains in the first direction is W2, W2 is less than or equal to 2 μm and greater than or equal to 0.5 μm.

[0023] In this way, the spacing between the two adjacent monitoring chains is not too small (determined by design rules) to be inconvenient for preparation, and the spacing between the two monitoring chains is not too large to better monitor the crack propagation (for example, if the spacing is too large, the crack may extend between the two adjacent monitoring chains, but the specific position cannot be determined, and the accuracy of the measured length of the crack is low).

[0024] According to a first aspect, or any possible implementation mode of the first aspect, the width of the crack propagation monitoring structure is W3, W3 is greater than or equal to 5 μm and less than or equal to 10 μm, that is, the distance between the outer side of the first monitoring chain (in the first direction, the side of the first monitoring chain away from the second monitoring chain) and the outer side of the last monitoring chain (in the first direction, the side of the last monitoring chain away from the second-to-last monitoring chain) is between 5 μm and 10 μm. The width of the crack propagation monitoring structure is set to be between 5 μm and 10 μm, which neither fails to achieve the monitoring purpose because the width of the crack propagation monitoring structure is too small, nor fails to meet the monitoring specification because the width of the crack propagation monitoring structure is too large.

[0025] According to a second aspect, the embodiments of the present application provide a wafer, which comprises the crack propagation monitoring structure according to the first aspect and any possible implementation mode of the first aspect.

[0026] The second aspect and any possible implementation mode of the second aspect correspond to the first aspect and any possible implementation mode of the first aspect, respectively. The technical effects corresponding to the second aspect and any possible implementation mode of the second aspect can be referred to the technical effects corresponding to the first aspect and any possible implementation mode of the first aspect, which will not be described here.

[0027] According to the second aspect, the wafer comprises: a substrate; an interconnection dielectric layer arranged on one side of the substrate, comprising a plurality of chip arrangement regions arranged at intervals, a cutting channel being formed between two adjacent chip arrangement regions, the interconnection dielectric layer further comprising at least one crack propagation monitoring region arranged on at least one side of the cutting channel, and a crack propagation monitoring structure arranged in the crack propagation monitoring region.

[0028] Of course, the crack propagation monitoring structure can also be arranged in the cutting channel, which is not limited in the present application.

[0029] According to the second aspect, or any possible implementation mode of the second aspect, the distance between the first monitoring chain of the crack propagation monitoring structure and the cutting channel is H1, H1 is greater than or equal to 0.5 μm and less than or equal to 2 μm, wherein the first monitoring chain is the monitoring chain with the smallest distance to the cutting channel among the plurality of monitoring chains.

[0030] In this way, the crack propagation cannot be detected because the crack propagation monitoring structure is too far away from the cutting channel, and only a partial length of the crack can be monitored because the crack propagation monitoring structure is too close to the cutting channel.

[0031] According to a second aspect, or any possible implementation mode of the second aspect, the distance between the last monitoring chain of the crack propagation monitoring structure and the cutting path is H2, H2 is greater than or equal to 5.5 μm and less than or equal to 12 μm, wherein the last monitoring chain is the monitoring chain with the largest distance to the cutting path in the plurality of monitoring chains. That is, the length of the crack monitored by the crack propagation monitoring structure is generally not more than 12 μm, for example, can be 10 μm, that is, the crack propagation monitoring structure can monitor a crack with a length of 12 μm, for example, can be 10 μm, if the length of the crack exceeds 10 μm, it indicates that the crack propagation of the wafer is very fast, which cannot meet the requirements of subsequent processes.

[0032] In a third aspect, the embodiments of the present application provide a crack propagation monitoring method, which is applied to the corresponding wafer as described in the second aspect and any possible implementation mode of the second aspect. The crack propagation monitoring method comprises: after the wafer is cut, testing the resistance value of the monitoring chain on the wafer to be tested, wherein the wafer to be tested is the part of the wafer including the crack propagation monitoring structure after the wafer is cut; if the resistance value of at least one monitoring chain in the plurality of monitoring chains is less than a first preset value, the wafer to be tested is placed in a test environment to perform a temperature cycle test, and the change rule of the crack propagation length and the temperature cycle number is determined.

[0033] That is, after the wafer is cut, as long as not all monitoring chains are broken, the wafer to be tested will be placed in a test environment to perform a temperature cycle test, and the change rule of the crack propagation length and the temperature cycle number is determined.

[0034] Through the crack propagation monitoring method, the relationship between the crack propagation and the temperature cycle stress can be determined, which is convenient for subsequent reliability evaluation.

[0035] According to the third aspect, if the resistance value of at least one monitoring chain in the plurality of monitoring chains is less than a first preset value, the wafer to be tested is placed in a test environment to perform a temperature cycle test, and the change rule of the crack propagation length and the temperature cycle number is determined, comprising: if the resistance value of the first monitoring chain is less than the first preset value, the wafer to be tested is placed in a test environment to perform a temperature cycle test, and the change rule of the crack propagation length and the temperature cycle number is determined.

[0036] If the resistance value of the first monitoring chain is greater than a second preset value, each monitoring chain is taken as a current monitoring chain in turn according to the monitoring chain arrangement order from the second monitoring chain, until the resistance value of one of the monitoring chains is less than the first preset value, the length of the position of the previous monitoring chain of the monitoring chain with the resistance value less than the first preset value is determined as the length of the crack generated when the wafer is cut, and the wafer to be tested is placed in a test environment to perform a temperature cycle test, and the change rule of the crack propagation length and the temperature cycle number is determined.

[0037] That is, after the wafer is cut, the first monitoring chain is tested first. If the first monitoring chain is not broken (the resistance of the first monitoring chain is less than the first preset value), it indicates that the length of the crack generated during the wafer cutting is small and does not extend to the position of the first monitoring chain. That is, all the monitoring chains will not be broken after the wafer is cut and before the temperature cycle stress is performed. The temperature cycle experiment can be further performed to determine the change rule of the crack propagation length and the number of temperature cycles. If the first monitoring chain is broken (the resistance of the first monitoring chain is greater than the second preset value), it indicates that the crack generated during the wafer cutting (i.e., the crack of the wafer before the temperature cycle experiment is performed) has extended to the position of the first monitoring chain. Then, it is further determined whether the crack extends to the position of the second monitoring chain, the position of the third monitoring chain, the position of the fourth monitoring chain, etc. As long as the crack does not extend to the position of the last monitoring chain during the wafer cutting process, the temperature cycle experiment can be further performed to determine the change rule of the crack propagation length and the number of temperature cycles. If the crack generated during the wafer cutting has extended to the position of the last monitoring chain, for example, the distance from the last monitoring chain to the cutting path is 12 μm, it indicates that the length of the crack generated during the wafer cutting is 12 μm, which will affect the functional area of the chip. Therefore, the chip cannot be applied to electronic devices.

[0038] For example, the first monitoring chain is the first monitoring chain in the following content.

[0039] According to the third aspect, the wafer to be tested is placed in a test environment to perform a temperature cycle experiment to determine the change rule of the crack propagation length and the number of temperature cycles, including: placing the wafer to be tested in a test environment to perform a first preset number of temperature cycles; if the resistance of the preset monitoring chain is greater than the second preset value, starting from the next monitoring chain of the preset monitoring chain, each monitoring chain is sequentially taken as a current monitoring chain for resistance testing according to the monitoring chain arrangement order until the resistance of the current monitoring chain is less than the first preset value, and it is determined that the length of the position of the previous monitoring chain of the current monitoring chain is the length of the crack under the first preset number of temperature cycles, wherein the preset monitoring chain is the monitoring chain with the smallest distance to the cutting position (i.e., the cutting path) and not broken after the wafer is cut.

[0040] For example, the number of monitoring chains is five. If the resistance of the first monitoring chain is greater than the second preset value, it indicates that the first monitoring chain is broken, and the resistance of the second monitoring chain (the current monitoring chain at this time) is tested. If the resistance of the second monitoring chain is less than the first preset value, it indicates that the second monitoring chain is not broken, and it further indicates that the crack extends to the position of the first monitoring chain but does not extend to the position of the second monitoring chain. Then, it is determined that the length of the position of the previous monitoring chain (i.e., the first monitoring chain) of the second monitoring chain is the length of the crack under the first preset number of temperature cycles.

[0041] For example, the number of monitoring chains is five. If the resistance of the first monitoring chain is greater than the second preset value, it indicates that the first monitoring chain is broken, and the resistance of the second monitoring chain (the current monitoring chain) is tested. If the resistance of the second monitoring chain is also greater than the second preset value, it indicates that the second monitoring chain is also broken, and the resistance of the third monitoring chain (the current monitoring chain) is tested. If the resistance of the third monitoring chain is also greater than the second preset value, it indicates that the third monitoring chain is also broken, and the resistance of the fourth monitoring chain (the current monitoring chain) is tested. If the resistance of the fourth monitoring chain is also greater than the second preset value, it indicates that the fourth monitoring chain is also broken, and the resistance of the fifth monitoring chain (the current monitoring chain) is tested. If the resistance of the fifth monitoring chain is less than the first preset value, it indicates that the fifth monitoring chain is not broken, and the crack has expanded to the position of the fourth monitoring chain but not to the position of the fifth monitoring chain. Therefore, the length of the position of the fourth monitoring chain (the previous monitoring chain of the fifth monitoring chain) is determined as the length of the crack under the first preset number of temperature cycles.

[0042] According to a third aspect, or any possible implementation of the third aspect, if the resistance of the preset monitoring chain is less than the first preset value, starting from the second preset number of temperature cycles, each temperature cycle number is sequentially taken as a current temperature cycle number for the experiment in the order of the temperature cycle number arrangement, wherein the temperature cycle numbers are sequentially increased. The preset monitoring chain is the monitoring chain that is not broken and has the smallest distance to the cutting position after the wafer is cut. If the resistance of the preset monitoring chain is less than the first preset value under the current temperature cycle number, the step of sequentially taking each temperature cycle number as a current temperature cycle number for the experiment in the order of the temperature cycle number arrangement is continued until all temperature cycle numbers are tested, and the chip formed after the wafer is cut is determined to be qualified.

[0043] That is, when the wafer to be tested is placed in the test environment for the first preset number of temperature cycles, the resistance of the preset monitoring chain is less than the first preset value, that is, the preset monitoring chain is not broken, and the crack has not expanded to the position of the preset monitoring chain. Therefore, it is not necessary to test the resistance of the subsequent monitoring chain (because the crack will not expand to the position of the subsequent monitoring chain). Instead, the number of temperature cycles needs to be increased to determine whether the preset monitoring chain is broken, that is, after increasing the number of temperature cycles, whether the crack will expand to the position of the preset monitoring chain.

[0044] For example, the temperature cycle times include a first preset number of temperature cycles, a second preset number of temperature cycles, a third preset number of temperature cycles, a fourth preset number of temperature cycles, and a fifth preset number of temperature cycles. When the wafer to be tested is placed in the test environment for the first preset number of temperature cycles, if the resistance of the preset monitoring chain is less than the first preset value, it indicates that the preset monitoring chain is not broken, and thus the crack does not extend to the position of the preset monitoring chain when the wafer to be tested is placed in the test environment for the first preset number of temperature cycles. Then, the wafer to be tested is subjected to the second preset number of temperature cycles (the current temperature cycle time), and if the resistance of the preset monitoring chain is still less than the first preset value, it indicates that the preset monitoring chain is still not broken, and thus the crack does not extend to the position of the preset monitoring chain when the wafer to be tested is placed in the test environment for the second preset number of temperature cycles. Then, the wafer to be tested is subjected to the third preset number of temperature cycles (the current temperature cycle time), and if the resistance of the preset monitoring chain is still less than the first preset value, it indicates that the preset monitoring chain is still not broken, and thus the crack does not extend to the position of the preset monitoring chain when the wafer to be tested is placed in the test environment for the third preset number of temperature cycles. Then, the wafer to be tested is subjected to the fourth preset number of temperature cycles (the current temperature cycle time), and if the resistance of the preset monitoring chain is still less than the first preset value, it indicates that the preset monitoring chain is still not broken, and thus the crack does not extend to the position of the preset monitoring chain when the wafer to be tested is placed in the test environment for the fourth preset number of temperature cycles. Then, the wafer to be tested is subjected to the fifth preset number of temperature cycles (the current temperature cycle time), and if the resistance of the preset monitoring chain is still less than the first preset value, it indicates that the preset monitoring chain is still not broken, and thus the crack does not extend to the position of the preset monitoring chain when the wafer to be tested is placed in the test environment for the fifth preset number of temperature cycles. That is, after the wafer to be tested is placed in the test environment for all preset numbers of temperature cycles, the crack does not extend to the position of the preset monitoring chain, indicating that the chip formed after the wafer is cut is qualified.

[0045] According to a third aspect, or any possible implementation mode of the third aspect, if the resistance of the preset monitoring chain at the current temperature cycle time is greater than the second preset value, starting from the next monitoring chain of the preset monitoring chain, each monitoring chain is sequentially taken as the current monitoring chain for resistance testing according to the monitoring chain arrangement order until the resistance of the current monitoring chain is less than the first preset value, and the length of the position of the previous monitoring chain of the current monitoring chain is determined as the length of the crack at the current temperature cycle time.

[0046] For example, the temperature cycle times include a first preset number of temperature cycles, a second preset number of temperature cycles, a third preset number of temperature cycles, a fourth preset number of temperature cycles, and a fifth preset number of temperature cycles, and the number of the monitoring chains is five. When the wafer to be tested is placed in the test environment to perform the first preset number of temperature cycles, if the resistance of the preset monitoring chain is less than the first preset value, it indicates that the preset monitoring chain is not broken, and thus it indicates that the crack does not expand to the position of the preset monitoring chain when the wafer to be tested is placed in the test environment to perform the first preset number of temperature cycles. Then, the wafer to be tested is subjected to the second preset number of temperature cycles (the current temperature cycle times), and if the resistance of the preset monitoring chain is greater than the second preset value, it indicates that the preset monitoring chain is broken, and thus it is necessary to determine the specific position of the crack expansion under the current temperature cycle times, for example, to continue to test the resistance of the next monitoring chain (the current monitoring chain) of the preset monitoring chain. If the resistance of the next monitoring chain of the preset monitoring chain is less than the first preset value, it indicates that the next monitoring chain of the preset monitoring chain is not broken, and thus it is determined that the length of the position of the preset monitoring chain is the length of the crack under the second preset number of temperature cycles.

[0047] According to a third aspect, or any possible implementation of the third aspect, the wafer to be tested is placed in the test environment to perform the temperature cycle experiment, and the change rule of the crack expansion length and the temperature cycle times is determined. The method further includes: performing the next preset number of temperature cycles of the current temperature cycle times on the wafer to be tested, determining the length of the crack under the next preset number of temperature cycles, and repeating the above until all the monitoring chains are broken or all the temperature cycle times are tested.

[0048] That is, when the wafer to be tested is subjected to the temperature cycle experiment, the wafer to be tested is first placed in the test environment to perform the first preset number of temperature cycles, and the position of the crack expansion under the temperature cycle times is determined. Then, the temperature cycle times are increased, for example, the second preset number of temperature cycles is performed, and the position of the crack expansion under the temperature cycle times is determined. Then, the temperature cycle times are further increased, for example, the third preset number of temperature cycles is performed, and the position of the crack expansion under the temperature cycle times is determined. In this way, the length of the crack under each temperature cycle times is determined, and thus the corresponding relationship between the crack length and the temperature cycle times is determined. BRIEF DESCRIPTION OF DRAWINGS

[0049] Figure 1 A structural schematic diagram of a wafer is shown;

[0050] Figure 2 A structural schematic diagram of an interconnection dielectric layer before wafer cutting is shown;

[0051] Figure 3 A structural schematic diagram of an interconnection dielectric layer after wafer cutting is shown;

[0052] Figure 4a A structure schematic diagram of a wafer provided by an embodiment of the present application is shown in FIG. 1.

[0053] Figure 4b Another structure schematic diagram of a wafer provided by an embodiment of the present application is shown in FIG. 2.

[0054] Figure 4c Another structure schematic diagram of a wafer provided by an embodiment of the present application is shown in FIG. 3.

[0055] Figure 5 A structure schematic diagram of an interconnection medium layer provided by an embodiment of the present application is shown in FIG. 4.

[0056] Figure 6 A position relationship diagram of a crack propagation monitoring structure and a cutting path provided by an embodiment of the present application is shown in FIG. 5.

[0057] Figure 7 A structure schematic diagram of a crack propagation monitoring structure provided by an embodiment of the present application is shown in FIG. 6.

[0058] Figure 8 A cross-sectional view of the crack propagation monitoring structure shown in FIG. 6 along the direction of AA' is shown in FIG. 7. Figure 7

[0059] A cross-sectional view of the crack propagation monitoring structure shown in FIG. 6 along the direction of BB' is shown in FIG. 8. Figure 9 Figure 7

[0060] Another structure schematic diagram of a crack propagation monitoring structure provided by an embodiment of the present application is shown in FIG. 9. Figure 10

[0061] Another structure schematic diagram of a crack propagation monitoring structure provided by an embodiment of the present application is shown in FIG. 10. Figure 11

[0062] A flowchart of a crack propagation monitoring method provided by an embodiment of the present application is shown in FIG. 11. Figure 12

[0063] A flowchart of a method for placing a wafer to be tested in a test environment to perform a temperature cycle experiment, and determining the change rule of crack propagation length and temperature cycle number provided by an embodiment of the present application is shown in FIG. 12. Figure 13 DETAILED DESCRIPTION

[0064] The technical solutions in the embodiments of the present application will be described clearly and completely below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are only some of the embodiments of the present application, rather than all the embodiments of the present application. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative labor fall within the scope of protection of the present application. ​​

[0065] The term "and / or", merely describes an associated relationship, which means that there can be three relationships, for example, A and / or B, which can represent: A exists alone, A and B exist together, and B exists alone.

[0066] The terms "first" and "second" and the like in the description and claims of the application are used for distinguishing between similar elements and not necessarily for describing a specific sequential or chronological order. For example, a first target object and a second target object are used for distinguishing between two structurally similar objects, and not necessarily for describing one object before or after another.

[0067] In the embodiments of the present application, the words "exemplary" and "for example" are used to mean serving as an example, instance, or illustration. Any implementation or design scheme described as "exemplary" or "for example" in the embodiments of the present application should not be construed as being preferred or advantageous over other implementations or design schemes. In fact, the term "exemplary" or "for example" is used to present concepts in a concrete manner.

[0068] In the description of the embodiments of the present application, the meaning of "a plurality of" is two or more, unless otherwise specified. For example, a plurality of processing units means two or more processing units; a plurality of systems means two or more systems.

[0069] As used herein, "perpendicular", "equal" includes the stated case and the case similar to the stated case within an acceptable deviation range, wherein the acceptable deviation range is determined by a person of ordinary skill in the art considering the measurement being discussed and the error related to the measurement of the specific quantity (i.e., the limitation of the measurement system). For example, "perpendicular" includes absolute perpendicular and approximate perpendicular, wherein the acceptable deviation range of the approximate perpendicular can be, for example, a deviation within 5°. "Equal" includes absolute equality and approximate equality, wherein the acceptable deviation range of the approximate equality can be, for example, that the difference between the two equalities is less than or equal to 5% of either one.

[0070] The connection relationship described in the present application refers to direct or indirect connection. For example, A is connected with B, which can be that A is directly connected with B, or A is indirectly connected with B through one or more other electrical components, for example, A can be directly connected with C, and C is directly connected with B, so that A is connected with B through C.

[0071] On a wafer, usually thousands of chips are formed, and a certain gap, for example, a gap of 60-150 μm (for example, a gap of 80 μm), is left between adjacent chips, which can be referred to as a cutting path (also referred to as a cutting groove). The cutting path can be cut to separate the chips on the wafer.

[0072] As shown in Figure 1 , Figure 1 A structural diagram of a wafer is shown. The wafer 001 includes a substrate 020 and an interconnection dielectric layer 010 located on one side of the substrate 020. The interconnection dielectric layer 010 is a multilayer structure, as shown in Figure 2 , Figure 2 A structural diagram of the interconnection dielectric layer before the wafer is cut is shown. The interconnection dielectric layer 010 includes a plurality of dielectric layers 011, a plurality of etching stop layers 012, a plurality of conductive layers 013, and a plurality of vias 014. The plurality of dielectric layers 011 and the plurality of etching stop layers 012 are stacked in order of the dielectric layers 011 and the etching stop layers 012, and each dielectric layer 011 corresponds to a conductive layer 013. The plurality of vias 014 penetrate the dielectric layers 011 and the etching stop layers 012 in the stacking direction to electrically connect adjacent two conductive layers 013.

[0073] As shown in Figure 3 , Figure 3 A structural diagram of the interconnection dielectric layer after the wafer is cut is shown. When the wafer 01 is cut, delamination or cracks are easily generated at the cutting position. For example, due to insufficient adhesion between the dielectric layer 011 and the adjacent etching stop layer 012, or mismatch in the coefficient of thermal expansion (CTE) therebetween, under the action of stress (for example, thermal stress generated by heat generated by laser cutting; or mechanical force generated by knife cutting), the dielectric layer 011 has a small crack or delamination occurs between the dielectric layer and the etching stop layer. If the crack or delamination extends into the chip, the chip fails, affecting the performance of the electronic device using the chip.

[0074] In addition, in some embodiments, in order to monitor the quality of the wafer 001 itself (such as monitoring the process stability and fluctuation of the production line), a wafer test structure (not shown in the figure) is provided on the cutting path of the wafer 001 during the design stage. When the wafer 001 is cut, the wafer test structure is generally touched. The wafer test structure is generally metal, which can accelerate the conduction of the thermal stress generated during cutting of the wafer, and make the dielectric layer 011 more prone to cracks or delamination due to CTE mismatch during cutting, affecting the quality of the chip after cutting.

[0075] To detect the length of cracks generated during wafer dicing (001), a crack detector can be placed on one side of the dicing chute at a predetermined distance. This detector can detect whether the crack has extended to its location; that is, it can only detect cracks that have extended to a fixed length (i.e., a predetermined distance). However, research has shown that cracks or delamination generated during wafer dicing may further extend due to subsequent temperature changes. For example, the crack may not have reached the chip's interior during dicing, but when the chip is used in electronic devices, the temperature changes during use can cause the crack to extend further, potentially penetrating the chip and causing it to fail, thus affecting the performance of the electronic devices using the chip.

[0076] Based on this, embodiments of this application provide a crack propagation monitoring structure and a crack propagation monitoring method. The crack propagation monitoring structure provided in this application embodiment can be applied to a wafer, specifically, to the interconnect dielectric layer of the wafer. This crack propagation monitoring structure can monitor crack growth, capture crack propagation caused during wafer dicing, and thus prevent device damage. It also provides the relationship between crack propagation and temperature cycling stress, which is convenient for subsequent reliability assessment.

[0077] The specific structure of the crack propagation monitoring structure provided in the embodiments of this application will be described below with reference to the wafer.

[0078] like Figure 4a , Figure 4b and Figure 4c As shown, Figure 4a This is a schematic diagram of a wafer structure provided in an embodiment of this application. Figure 4b This is a schematic diagram of another wafer structure provided in an embodiment of this application. Figure 4c This is a schematic diagram of another wafer structure provided in an embodiment of the present application. The wafer 10 includes a substrate 11 and an interconnect dielectric layer 12 located on one side of the substrate 11.

[0079] The substrate 11 serves to support the interconnect dielectric layer 12. The material of the substrate 11 can be selected according to the actual situation. For example, the material of the substrate 11 can be silicon (Si), sapphire (Al2O3), or silicon carbide (SiC). The interior of the substrate 11 may include functional regions (not shown in the figure), and the interior of the functional regions may contain electronic devices (such as transistors).

[0080] like Figure 5 As shown, Figure 5 This is a schematic diagram of an interconnect dielectric layer provided in an embodiment of this application. The interconnect dielectric layer 12 has a multilayer structure, including multiple dielectric layers, multiple etch stop layers, and multiple conductive layers. Figure 5Take five layers of dielectric layer, etching stop layer and conductive layer as an example for illustration. The five layers of dielectric layer include first dielectric layer 1211, second dielectric layer 1212, third dielectric layer 1213, fourth dielectric layer 1214 and fifth dielectric layer 1215, the five layers of etching stop layer include first etching stop layer 1221, second etching stop layer 1222, third etching stop layer 1223, fourth etching stop layer 1224 and fifth etching stop layer 1225, the five layers of conductive layer include first conductive layer 1231, second conductive layer 1232, third conductive layer 1233, fourth conductive layer 1234 and fifth conductive layer 1235, the interconnection dielectric layer 12 is stacked in the order of first etching stop layer 1221, first dielectric layer 1211, second etching stop layer 1222, second dielectric layer 1212, third etching stop layer 1223, third dielectric layer 1213, fourth etching stop layer 1224, fourth dielectric layer 1214, fifth etching stop layer 1225 and fifth dielectric layer 1215, each layer of dielectric layer corresponds to a layer of conductive layer, i.e. the first dielectric layer 1211 corresponds to the first conductive layer 1231, the second dielectric layer 1212 corresponds to the second conductive layer 1232, the third dielectric layer 1213 corresponds to the third conductive layer 1233, the fourth dielectric layer 1214 corresponds to the fourth conductive layer 1234, and the fifth dielectric layer 1215 corresponds to the fifth conductive layer 1235. Each layer of dielectric layer and each layer of etching stop layer are provided with at least one through hole 124, and the through hole 124 can conduct the adjacent two layers of conductive layer.

[0081] The interconnection dielectric layer 12 further includes a connecting dielectric layer 125, a connecting pad layer 126 and a passivation layer 127, the connecting dielectric layer 125 corresponds to the connecting pad layer 126, the connecting dielectric layer 125 is provided with at least one through hole 124, which can conduct the connecting pad layer 126 and the fifth conductive layer 1235. The passivation layer 127 is arranged on the connecting pad layer 126, and the passivation layer 127 is provided with a through hole to expose the connecting pad layer 126. By arranging the passivation layer 127 on the connecting dielectric layer 125, the function of protecting the connecting dielectric layer 125 can be achieved.

[0082] The material of the above-mentioned dielectric layer can be silicon oxide or silicon nitride, and the silicon oxide can be doped with carbon and hydrogen to form a low-k dielectric layer. The material of the conductive layer and the connecting pad layer 126 can be aluminum or the like, and when the material of the conductive layer and / or the connecting pad layer 126 is aluminum, a small amount of copper can also be doped in the aluminum. The material of the conductive layer and the connecting pad layer 126 can be the same or different.

[0083] Continuing to refer to Figure 4aThe interconnection medium layer 12 includes a plurality of chip setting areas 12a arranged at intervals, and a cutting path 12b is formed between two adjacent chip setting areas 12a. It can be understood that the chip setting area 12a in the interconnection medium layer 12 refers to a part of the area of the interconnection medium layer 12 that can be used to manufacture a chip after cutting. In the process of manufacturing the chip, the cutting is performed along the cutting path 12b, and the chip setting area 12a in the interconnection medium layer 12 and the corresponding part of the substrate 10 form the basic structure of the chip.

[0084] The functional area can be located at the side surface of the substrate 11 close to the interconnection medium layer 12, and the functional area and the chip setting area 12a are arranged opposite to each other in the thickness direction of the substrate 11. The multilayer conductive layer and the connection pad 126 in the chip setting area 12a are conductive to each other to form a conductive structure for connecting the electronic device in the functional area and the device outside the chip. That is, the multilayer conductive layer and the connection pad 126 in the chip setting area 12a are conductive to each other to form a conductive structure, which can be connected with the electronic device in the functional area and functions as a lead to connect the electronic device in the functional area and the device outside the chip.

[0085] In combination with Figure 6 as shown, Figure 6 A crack propagation monitoring structure and a position relationship diagram of a cutting path provided in the embodiment of the present application, the interconnection medium layer 12 further includes at least one crack propagation monitoring area 12c, and the crack propagation monitoring area 12c can be located at least one side of the cutting path 12b. The crack propagation monitoring area 12c is provided with a crack propagation monitoring structure 128, and the distance between the crack propagation monitoring structure 128 and the cutting path 12b is H1, which can be greater than or equal to 0.5 μm and less than or equal to 2 μm, such as 0.5 μm, 0.8 μm, 1 μm, 1.5 μm or 2 μm, etc.

[0086] It should be noted that the number and position of the crack propagation monitoring area 12c and the crack propagation monitoring structure 128 are not limited in the embodiment of the present application, as long as the relationship between the crack propagation and the temperature cycle stress is determined by the crack propagation monitoring structure 128.

[0087] In other optional embodiments of the present application, as shown in Figure 4b wherein, Figure 4b Only the crack propagation monitoring area 12c is shown, and the crack propagation monitoring structure 128 in the crack propagation monitoring area 12c is not shown, and the crack propagation monitoring area 12c and the crack propagation monitoring structure 128 can also be located in the cutting path 12b.

[0088] When the crack propagation monitoring zone 12c is located on at least one side of the cutting channel 12b, the number of crack propagation monitoring zones 12c and crack propagation monitoring structures 128 can be one, and this one crack propagation monitoring structure 128 is located on one side of one of the cutting channels 12b; the number of crack propagation monitoring zones 12c and crack propagation monitoring structures 128 can be multiple, and multiple crack propagation monitoring structures 128 are respectively located on one side of multiple cutting channels 12b (e.g., Figure 4a (as shown) or both sides (such as) Figure 4c (As shown).

[0089] When the crack propagation monitoring zone 12c is located within the cutting channel 12b, the number of crack propagation monitoring zones 12c and crack propagation monitoring structures 128 can be one, and the one crack propagation monitoring structure 128 is located within one of the cutting channels 12b; the number of crack propagation monitoring zones 12c and crack propagation monitoring structures 128 can be multiple, and the multiple crack propagation monitoring structures 128 are located within multiple cutting channels 12b respectively.

[0090] like Figure 7 and Figure 8 As shown, Figure 7 This is a schematic diagram of a crack propagation monitoring structure provided in an embodiment of this application. Figure 8 for Figure 7 The diagram shows a cross-sectional view of the crack propagation monitoring structure along the AA' direction. The crack propagation monitoring structure 128 includes multiple monitoring chains 1281 arranged along a first direction X and extending along a second direction Y. The first direction X and the second direction Y intersect; for example, the first direction X and the second direction Y can be perpendicular. For example, the first direction X can be the width direction of the cutting channel 12b, and the second direction Y can be the extension direction of the cutting channel 12b.

[0091] Combination Figure 6 The distance between the last monitoring chain 1281 of the crack propagation monitoring structure 128 and the cutting path 12b is H2, where H2 is greater than or equal to 5.5 μm and less than or equal to 12 μm, such as H2 being 5.5 μm, 6 μm, 7 μm, 8 μm, 9 μm, 10 μm, 11 μm, or 12 μm. The last monitoring chain 1281 is the monitoring chain 1281 with the largest distance from the cutting path 12b among the multiple monitoring chains 1281.

[0092] In other words, the length of the crack monitored by the crack propagation monitoring structure 128 generally does not exceed 12μm. That is, the crack propagation monitoring structure 128 can monitor cracks with a length of 12μm, for example, 10μm. If the crack length exceeds 10μm, it means that the crack propagation of the wafer 10 is very fast and cannot meet the requirements of subsequent processes.

[0093] In the second direction Y, each monitoring chain 1281 includes a plurality of monitoring units 12811 spaced apart, each monitoring unit 12811 includes at least one monitoring layer, for example, each monitoring unit 12811 includes N monitoring layers, N is a positive integer greater than or equal to 1, N can be 1, 2, 3, 4, 5, 6 or 7, etc. For example, when N is 2, each monitoring unit 12811 includes two monitoring layers, that is, each monitoring unit 12811 includes a first monitoring layer and a second monitoring layer; for another example, when N is 7, each monitoring unit 12811 includes seven monitoring layers, that is, each monitoring unit 12811 includes a first monitoring layer, a second monitoring layer, a third monitoring layer, a fourth monitoring layer, a fifth monitoring layer, a sixth monitoring layer and a seventh monitoring layer, a person skilled in the art can determine the specific value of N according to the actual situation, that is, the number of monitoring layers can be set according to the actual situation, and the meaning of N in the following content is the same. The monitoring layers of the monitoring unit 12811 and the above-mentioned conductive layers can be formed in the interconnection dielectric layer 12 by the same semiconductor process.

[0094] For example, the monitoring unit 12811 includes six monitoring layers, which are a first monitoring layer M11, a second monitoring layer M12, a third monitoring layer M13, a fourth monitoring layer M14, a fifth monitoring layer M15 and a sixth monitoring layer M16, the first monitoring layer M11 and the first conductive layer 1231 are formed by the same semiconductor process, the second monitoring layer M12 and the second conductive layer 1232 are formed by the same semiconductor process, the third monitoring layer M13 and the third conductive layer 1233 are formed by the same semiconductor process, the fourth monitoring layer M14 and the fourth conductive layer 1234 are formed by the same semiconductor process, the fifth monitoring layer M15 and the fifth conductive layer 1235 are formed by the same semiconductor process, and the sixth monitoring layer M16 and the connection pad layer 126 are formed by the same semiconductor process. It can also be said that when the wafer 10 is prepared, the conductive layer is not only located in the chip setting area 12a, but also located in the crack propagation monitoring area 12c, and the conductive layer located in the crack propagation monitoring area 12c is also called a monitoring layer. The monitoring layers of the monitoring unit 12811 and the above-mentioned conductive layers are formed in the interconnection dielectric layer 12 by the same semiconductor process, which can reduce the preparation steps and simplify the process.

[0095] Each layer of dielectric layer and each layer of etching stop layer located in the crack propagation monitoring area 12c is also provided with at least one through hole 124, which can conduct adjacent two layers of monitoring layers in the same monitoring unit 12811.

[0096] Each monitoring chain 1281 further comprises a first connecting unit 12812 and a second connecting unit 12813. In the same monitoring chain 1281, except for the first monitoring unit 12811 and the last monitoring unit 12811, other monitoring units 12811 are connected to the monitoring units 12811 located on both sides (along the second direction Y) of the monitoring unit 12811 through the first connecting unit 12812 and the second connecting unit 12813, respectively.

[0097] The first connecting unit 12812 can be arranged in the same layer as one of the N layers of monitoring layers, and the second connecting unit 12813 can also be arranged in the same layer as one of the N layers of monitoring layers.

[0098] For example, continuing to refer to Figure 7 and Figure 8 , the first connecting unit 12812 is arranged in the same layer as the first monitoring layer M11, and the second connecting unit 12813 is arranged in the same layer as the Nth monitoring layer. For example, when the plurality of monitoring layers comprises six monitoring layers, the second connecting unit 12813 is arranged in the same layer as the last monitoring layer (i.e., the sixth monitoring layer M16). In order to better distinguish the first monitoring layer M11, the last monitoring layer, and other monitoring layers (such as the second monitoring layer M12, the third monitoring layer M13, the fourth monitoring layer M14, and the fifth monitoring layer M15), Figure 7 and Figure 8 , the first monitoring layer M11 and the sixth monitoring layer M16 are respectively filled with different patterns.

[0099] The i-th monitoring unit 12811 and the i+1-th monitoring unit 12811 of each monitoring chain 1281 are connected through the first connecting unit 12812, and the i+1-th monitoring unit 12811 and the i+2-th monitoring unit 12811 are connected through the second connecting unit 12813, where i can be 1, 3, 5, 7, 9, …. In this way, three adjacent monitoring units 12811 form a inverted “Y” and a normal “Y”, respectively. A plurality of inverted “Y” and normal “Y” are arranged along the Y-axis direction in the order of inverted “Y” and normal “Y”, and are connected to each other in sequence to form a monitoring chain 1281.

[0100] Alternatively, the $i$-th monitoring unit 12811 and the $(i + 1)$-th monitoring unit 12811 of each monitoring chain 1281 are connected by a second connection unit 12813, and the $(i + 1)$-th monitoring unit 12811 and the $(i + 2)$-th monitoring unit 12811 are connected by a first connection unit 12812, where $i$ can be 1, 3, 5, 7, 9,.... In this way, a positive "J" and an inverted "J" are respectively formed between three adjacent monitoring units 12811, and multiple positive "J"s and inverted "J"s are arranged in sequence in the Y-axis direction in the order of positive "J" and inverted "J", and are sequentially connected to each other to form a monitoring chain 1281.

[0101] The size of the above-mentioned monitoring chain 1281 in the first direction X is W1, W1 is less than or equal to 2 μm and greater than or equal to 0.5 μm. Exemplarily, the size W1 of the monitoring chain 1281 in the first direction X is 0.5 μm, 0.8 μm, 1 μm, 1.5 μm, 2 μm, etc.

[0102] It can be understood that the size of the monitoring chain 1281 in the first direction X is the size of the monitoring unit 12811 of the monitoring chain 1281 in the first direction X. Specifically, it is the size of the monitoring layer in the monitoring unit 12811 in the first direction X. When the monitoring layer in the monitoring unit 12811 is multiple layers, it can be considered that the sizes of the multiple monitoring layers in the first direction X are equal.

[0103] The spacing between two adjacent monitoring chains 1281 in the first direction X is W2, W2 is less than or equal to 2 μm and greater than or equal to 0.5 μm. Exemplarily, the spacing W2 between two adjacent monitoring chains 1281 in the first direction X is 0.5 μm, 0.8 μm, 1 μm, 1.5 μm, 2 μm, etc.

[0104] It can be understood that the spacing between two adjacent monitoring chains 1281 in the first direction X is the spacing between the monitoring units 12811 in two adjacent monitoring chains 1281 in the first direction X.

[0105] The width of the above-mentioned crack propagation monitoring structure 128 in the first direction X is W3, W3 is greater than or equal to 5 μm and less than or equal to 10 μm. Exemplarily, the width W3 of the crack propagation monitoring structure 128 in the first direction X is 5 μm, 6 μm, 7 μm, 8 μm, 9 μm, 10 μm, etc.

[0106] That is, the distance between the outer side of the first monitoring chain 1281 (in the first direction X, the side of the first monitoring chain away from the second monitoring chain) and the outer side of the last monitoring chain 1281 (in the first direction X, the side of the last monitoring chain away from the second-to-last monitoring chain) is 5 μm to 10 μm. The width W3 of the crack propagation monitoring structure 128 is set to be between 5 μm and 10 μm, so that the crack propagation monitoring structure 128 does not fail to achieve the monitoring purpose because the width of the crack propagation monitoring structure 128 is too small, and does not fail to meet the monitoring specifications because the width of the crack propagation monitoring structure 128 is too large. It should be noted that the number of monitoring chains 1281 is not limited in the embodiments of the present application, and can be set according to actual conditions (such as the length of the crack to be monitored).

[0107] Continuing to refer to Figure 7 The crack propagation monitoring structure 128 further includes a plurality of connecting pieces 1282, which are used to connect adjacent two monitoring chains 1281. Except for the first monitoring chain 1281 and the last monitoring chain 1281, the opposite ends (in the Y-axis direction) of the other monitoring chains 1281 are connected to the monitoring chains 1281 located on the two sides (in the X-axis direction) of the monitoring chains 1281 through two connecting pieces 1282. That is, in the Y-axis direction, the monitoring chain 1281 includes opposite first and second connecting ends D1 and D2. Except for the first monitoring chain 1281 and the last monitoring chain 1281, the first connecting end D1 of the monitoring chain 1281 is connected to the first connecting end D1 of the monitoring chain 1281 located on one side of the monitoring chain 1281 through one connecting piece 1282, and the second connecting end D2 of the monitoring chain 1281 is connected to the second connecting end D2 of the monitoring chain 1281 located on the other side of the monitoring chain 1281 through another connecting piece 1282. In this way, the shape formed by the monitoring chains 1281 can be approximately "serpentine".

[0108] The connecting piece 1282 can be a monitoring unit 12811, that is, the connecting piece 1282 includes N layers of connecting layers, and the N layers of connecting layers and the N layers of monitoring layers are formed through the same semiconductor process. Alternatively, the connecting piece 1282 can be one of the monitoring layers in the monitoring unit 12811, that is, the connecting piece 1282 includes one layer of connecting layer, and the connecting layer and the monitoring layer are formed through the same semiconductor process. Whether the connecting piece 1282 is the monitoring unit 12811 or one of the monitoring layers in the monitoring unit 12811 can be determined according to the length of the monitoring chain 1281 and other reasons.

[0109] For example, continuing to refer to Figure 7The plurality of monitoring chains 1281 include a first monitoring chain (i.e., a first monitoring chain) 1281a, a second monitoring chain (i.e., a second monitoring chain) 1281b, a third monitoring chain (i.e., a third monitoring chain) 1281c, a fourth monitoring chain (i.e., a fourth monitoring chain) 1281d, and a fifth monitoring chain (i.e., a fifth monitoring chain) 1281e, wherein the first monitoring chain 1281a, the second monitoring chain 1281b, the third monitoring chain 1281c, the fourth monitoring chain 1281d, and the fifth monitoring chain 1281e are increasingly far away from the cutting path 12b. The second connecting end D2 of the first monitoring chain 1281a and the second connecting end D2 of the second monitoring chain 1281b are connected by a connecting piece 1282, wherein the connecting piece 1282 is a first monitoring layer M11 in the monitoring unit 12811; the first connecting end D1 of the second monitoring chain 1281b and the first connecting end D1 of the third monitoring chain 1281c are connected by a connecting piece 1282, wherein the connecting piece 1282 is a first monitoring layer M11 in the monitoring unit 12811; the second connecting end D2 of the third monitoring chain 1281c and the second connecting end D2 of the fourth monitoring chain 1281d are connected by a connecting piece 1282, wherein the connecting piece 1282 is a monitoring unit 12811; and the first connecting end D1 of the fourth monitoring chain 1281d and the first connecting end D1 of the fifth monitoring chain 1281e are connected by a connecting piece 1282, wherein the connecting piece 1282 is a monitoring unit 12811.

[0110] That is, the crack propagation monitoring structure 128 provided by the embodiments of the present application can be a daisy chain design structure stacked from the first monitoring layer M11 to the Nth monitoring layer M(1N) and alternately repeated.

[0111] Continuing to refer to Figure 7 The crack propagation monitoring structure 128 further includes a plurality of test pieces 1283, each monitoring chain 1281 corresponds to at least one test piece 1283, and the test piece 1283 corresponding to the monitoring chain 1281 is connected to the monitoring chain 1281. The test piece 1283 is used to determine whether the monitoring chain 1281 is disconnected, specifically, the test piece 1283 is used to determine whether the monitoring chain 1281 is disconnected according to the detected resistance of the monitoring chain 1281, when the monitoring chain 1281 is disconnected, it represents that the crack has propagated to the position of the monitoring chain 1281.

[0112] In combination with Figure 9 , Figure 9 For Figure 7A cross-sectional view of the crack propagation monitoring structure along the direction of BB' is shown. Each test piece 1283 includes a plurality of test layers, and the number of test layers corresponds to the number of monitoring layers. For example, each monitoring unit 12811 includes N monitoring layers, and each test piece 1283 includes N test layers, where N is a positive integer greater than or equal to 1. For example, the plurality of monitoring layers includes six monitoring layers, and each test piece 1283 includes six test layers. The six monitoring layers are a first monitoring layer M11, a second monitoring layer M12, a third monitoring layer M13, a fourth monitoring layer M14, a fifth monitoring layer M15, and a sixth monitoring layer M16. The six test layers are a first test layer M21, a second test layer M22, a third test layer M23, a fourth test layer M24, a fifth test layer M25, and a sixth test layer M26. The first test layer M21 and the first monitoring layer M11 are formed by the same semiconductor process. The second test layer M22 and the second monitoring layer M12 are formed by the same semiconductor process. The third test layer M23 and the third monitoring layer M13 are formed by the same semiconductor process. The fourth test layer M24 and the fourth monitoring layer M14 are formed by the same semiconductor process. The fifth test layer M25 and the fifth monitoring layer M15 are formed by the same semiconductor process. The sixth test layer M26 and the sixth monitoring layer M16 are formed by the same semiconductor process. An opening 1271 is formed in the passivation layer 127 in the crack propagation monitoring area 12c to expose at least a portion of the sixth test layer M26, so as to facilitate subsequent testing (described below, and thus is not described here).

[0113] For the arrangement of the test piece 1283, the embodiments of the present application do not limit the arrangement of the test piece 1283, as long as it can be determined whether the corresponding monitoring chain 1281 is disconnected.

[0114] In a possible implementation manner, as shown in Figure 10 Figure 10 FIG. 7 is a structural schematic diagram of another crack propagation monitoring structure provided by the embodiments of the present application. Each monitoring chain 1281 corresponds to a test piece 1283. An end of the monitoring chain 1281 that is not connected to the next monitoring chain 1281 is connected to the corresponding test piece 1283 by extending the jth monitoring layer of the monitoring unit 12811 at the end to the jth test layer of the corresponding test piece 1283, where j is a positive integer less than or equal to N.

[0115] ​It can also be said that, in addition to the first monitoring chain 1281, the preset end of the other monitoring chain 1281 is connected to the test piece 1283 by extending the jth monitoring layer of the monitoring unit 12811 to the jth test layer of the test piece 1283, where j is a positive integer less than or equal to N. The end of the first monitoring chain 1281 that is not connected to the second monitoring chain 1281 is connected to the test piece 1283 by extending the jth monitoring layer of the monitoring unit 12811 at the end to the jth test layer of the test piece 1283 corresponding thereto.

[0116] Still taking the crack propagation monitoring structure 128 including five monitoring chains 1281 (i.e. the first monitoring chain 1281a, the second monitoring chain 1281b, the third monitoring chain 1281c, the fourth monitoring chain 1281d and the fifth monitoring chain 1281e) as an example, the number of test pieces 1283 is five, the test piece 1283 corresponding to the first monitoring chain 1281a is the first test piece, the test piece 1283 corresponding to the second monitoring chain 1281b is the second test piece, the test piece 1283 corresponding to the third monitoring chain 1281c is the third test piece, the test piece 1283 corresponding to the fourth monitoring chain 1281d is the fourth test piece, and the test piece 1283 corresponding to the fifth monitoring chain 1281e is the fifth test piece. The first connecting end D1 (the end not connected with the second monitoring chain 1281b) of the first monitoring chain 1281a is connected with the first test piece by extending the sixth monitoring layer M16 of the first monitoring unit 12811 in the first monitoring chain 1281a to the sixth test layer M26 of the first test piece. The second connecting end D2 (the end not connected with the third monitoring chain 1281c) of the second monitoring chain 1281b is connected with the second test piece by extending the sixth monitoring layer M16 of the last monitoring unit 12811 in the second monitoring chain 1281b to the sixth test layer M26 of the second test piece. The first connecting end D1 (the end not connected with the fourth monitoring chain 1281d) of the third monitoring chain 1281c is connected with the third test piece by extending the first monitoring layer M11 of the first monitoring unit 12811 in the third monitoring chain 1281c to the first test layer M21 of the third test piece. The second connecting end D2 (the end not connected with the fifth monitoring chain 1281e) of the fourth monitoring chain 1281d is connected with the fourth test piece by extending the first monitoring layer M11 of the last monitoring unit 12811 in the fourth monitoring chain 1281d to the first test layer M21 of the fourth test piece. The first connecting end D1 (the end not connected with the next monitoring chain 1281d) of the fifth monitoring chain 1281c is connected with the fifth test piece by extending the sixth monitoring layer M16 of the first monitoring unit 12811 in the fifth monitoring chain 1281c to the sixth test layer M26 of the fifth test piece.

[0117] In this case, since the first test piece and the second test piece are connected with the first monitoring unit 12811 and the last monitoring unit 12811 of the first monitoring chain 1281a respectively, whether the first monitoring chain 1281a is disconnected can be determined through the first test piece and the second test piece; since the second test piece and the third test piece are connected with the last monitoring unit 12811 and the first monitoring unit 12811 of the second monitoring chain 1281b respectively, whether the second monitoring chain 1281b is disconnected can be determined through the second test piece and the third test piece; since the third test piece and the fourth test piece are connected with the first monitoring unit 12811 and the last monitoring unit 12811 of the third monitoring chain 1281c respectively, whether the third monitoring chain 1281c is disconnected can be determined through the third test piece and the fourth test piece; since the fourth test piece and the fifth test piece are connected with the last monitoring unit 12811 and the first monitoring unit 12811 of the fourth monitoring chain 1281d respectively, whether the fourth monitoring chain 1281d is disconnected can be determined through the fourth test piece and the fifth test piece.

[0118] For example, one probe of a device for detecting resistance (such as a semiconductor comprehensive tester) can be contacted with the sixth test layer M26 exposed by the opening 1271 in the first test piece, and the other probe can be contacted with the sixth test layer M26 exposed by the opening 1271 in the second test piece to determine the resistance of the first monitoring chain 1281a. Whether the first monitoring chain 1281a is broken can be determined based on the resistance of the first monitoring chain 1281a. Specifically, when the resistance of the first monitoring chain 1281a is measured to be large, such as greater than a second preset value, where the second preset value can be 1 megaohm or the like, it is determined that the first monitoring chain 1281a is broken, i.e., the crack has extended to the position of the first monitoring chain 1281a; when the resistance of the first monitoring chain 1281a is measured to be small, such as less than a first preset value, where the first preset value can be 100 ohms or 500 ohms or the like, it is determined that the first monitoring chain 1281a is not broken. Similarly, one probe of the semiconductor comprehensive tester can be contacted with the sixth test layer M26 exposed by the opening 1271 in the second test piece, and the other probe can be contacted with the sixth test layer M26 exposed by the opening 1271 in the third test piece to determine the resistance of the second monitoring chain 1281b. Whether the second monitoring chain 1281b is broken can be determined based on the resistance of the second monitoring chain 1281b. Specifically, when the resistance of the second monitoring chain 1281b is measured to be large, such as greater than the second preset value, it is determined that the second monitoring chain 1281b is broken, i.e., the crack has extended to the position of the second monitoring chain 1281b; when the resistance of the second monitoring chain 1281b is measured to be small, such as less than the first preset value, it is determined that the second monitoring chain 1281b is not broken. Similarly, one probe of the semiconductor comprehensive tester can be contacted with the sixth test layer M26 exposed by the opening 1271 in the third test piece, and the other probe can be contacted with the sixth test layer M26 exposed by the opening 1271 in the fourth test piece to determine the resistance of the third monitoring chain 1281c. Whether the third monitoring chain 1281c is broken can be determined based on the resistance of the third monitoring chain 1281c. Specifically, when the resistance of the third monitoring chain 1281c is measured to be large, such as greater than the second preset value, it is determined that the third monitoring chain 1281c is broken, i.e., the crack has extended to the position of the third monitoring chain 1281c; when the resistance of the third monitoring chain 1281c is measured to be small, such as less than the first preset value, it is determined that the third monitoring chain 1281c is not broken. Similarly, one probe of the semiconductor comprehensive tester can be contacted with the sixth test layer M26 exposed by the opening 1271 in the third test piece, and the other probe can be contacted with the sixth test layer M26 exposed by the opening 1271 in the fourth test piece to determine the resistance of the fourth monitoring chain 1281d. Whether the fourth monitoring chain 1281d is broken can be determined based on the resistance of the fourth monitoring chain 1281d.Specifically, when the resistance of the fourth monitoring chain 1281d is measured to be large, such as greater than the second preset value, it is determined that the fourth monitoring chain 1281d is broken, i.e., the crack has extended to the position of the fourth monitoring chain 1281d; when the resistance of the fourth monitoring chain 1281d is measured to be small, such as less than the first preset value, it is determined that the fourth monitoring chain 1281d is not broken.

[0119] Since the size of each monitoring chain 1281 in the first direction X is a constant value, and the distance between two adjacent monitoring chains 1281 is a constant value, the length of the crack can be determined based on the position of the monitoring chain 1281 to which the crack extends.

[0120] In the present implementation, since the first monitoring chain 1281a and the second monitoring chain 1281b share the second test piece, the second monitoring chain 1281b and the third monitoring chain 1281c share the third test piece, the third monitoring chain 1281c and the fourth monitoring chain 1281d share the fourth test piece, etc., the number of test pieces can be reduced, thereby reducing the preparation steps and simplifying the process.

[0121] In another possible implementation, continuing to refer to Figure 7 and Figure 9 Unlike Figure 10 , each monitoring chain 1281 corresponds to two test pieces 1283, both of which are located at the same end of the monitoring chain 1281 and are connected to the end, i.e., the end of the monitoring chain 1281 that is not connected to the next monitoring chain 1281, is connected to the two test pieces 1283 corresponding to it by extending the j-th monitoring layer of the monitoring unit 12811 of the monitoring chain 1281 to the j-th test layer of the two test pieces 1283 corresponding to it, where j is a positive integer less than or equal to N.

[0122] Still taking the crack propagation monitoring structure 128 including five monitoring chains 1281 (i.e. the first monitoring chain 1281a, the second monitoring chain 1281b, the third monitoring chain 1281c, the fourth monitoring chain 1281d and the fifth monitoring chain 1281e) as an example, the number of test pieces 1283 is ten, i.e. the number of first test pieces corresponding to the first monitoring chain 1281a is two, the number of second test pieces corresponding to the second monitoring chain 1281b is two, the number of third test pieces corresponding to the third monitoring chain 1281c is two, the number of fourth test pieces corresponding to the fourth monitoring chain 1281d is two, and the number of fifth test pieces corresponding to the fifth monitoring chain 1281e is two. The first connecting end D1 (the end not connected with the second monitoring chain 1281b) of the first monitoring chain 1281a is connected with the two first test pieces by respectively extending the sixth monitoring layer M16 of the first monitoring unit 12811 in the first monitoring chain 1281a to the sixth test layer M26 of the two first test pieces. The second connecting end D2 (the end not connected with the third monitoring chain 1281c) of the second monitoring chain 1281b is connected with the two second test pieces by respectively extending the sixth monitoring layer M16 of the last monitoring unit 12811 in the second monitoring chain 1281b to the sixth test layer M26 of the two second test pieces. The first connecting end D1 (the end not connected with the fourth monitoring chain 1281d) of the third monitoring chain 1281c is connected with the two third test pieces by respectively extending the first monitoring layer M11 of the first monitoring unit 12811 in the third monitoring chain 1281c to the first test layer M21 of the two third test pieces. The second connecting end D2 (the end not connected with the fifth monitoring chain 1281e) of the fourth monitoring chain 1281d is connected with the two fourth test pieces by respectively extending the first monitoring layer M11 of the last monitoring unit 12811 in the fourth monitoring chain 1281d to the first test layer M21 of the two fourth test pieces. The first connecting end D1 (the end not connected with the next monitoring chain 1281d) of the fifth monitoring chain 1281c is connected with the two fifth test pieces by respectively extending the sixth monitoring layer M16 of the first monitoring unit 12811 in the fifth monitoring chain 1281c to the sixth test layer M26 of the two fifth test pieces.

[0123] In this case, since the two first test pieces and the two second test pieces are connected with the first monitoring unit 12811 and the last monitoring unit 12811 of the first monitoring chain 1281a respectively, the four probes of the semiconductor comprehensive tester can be contacted with the sixth test layer M26 exposed by the two first test pieces and the two second test pieces through the opening 1271 respectively, and the resistance of the first monitoring chain 1281a is detected by Kelvin four-wire detection (four-terminal detection) to determine whether the first monitoring chain 1281a is disconnected; since the two second test pieces and the two third test pieces are connected with the last monitoring unit 12811 and the first monitoring unit 12811 of the second monitoring chain 1281b respectively, the four probes of the semiconductor comprehensive tester can be contacted with the sixth test layer M26 exposed by the two second test pieces and the two third test pieces through the opening 1271 respectively, and the resistance of the second monitoring chain 1281b is detected by four-terminal detection to determine whether the second monitoring chain 1281b is disconnected; since the third test piece and the fourth test piece are connected with the first monitoring unit 12811 and the last monitoring unit 12811 of the third monitoring chain 1281c respectively, the four probes of the semiconductor comprehensive tester can be contacted with the sixth test layer M26 exposed by the two third test pieces and the two fourth test pieces through the opening 1271 respectively, and the resistance of the third monitoring chain 1281c is detected by four-terminal detection to determine whether the third monitoring chain 1281c is disconnected; since the two fourth test pieces and the two fifth test pieces are connected with the last monitoring unit 12811 and the first monitoring unit 12811 of the fourth monitoring chain 1281d respectively, the four probes of the semiconductor comprehensive tester can be contacted with the sixth test layer M26 exposed by the two fourth test pieces and the two fifth test pieces through the opening 1271 respectively, and the resistance of the fourth monitoring chain 1281d is detected by four-terminal detection to determine whether the fourth monitoring chain 1281d is disconnected.

[0124] In the present embodiment, since the resistance is detected by four-terminal detection, the impedance of the contact resistance between the probe and the sixth test layer M26 can be eliminated, so that the resistance of each monitoring chain 1281 detected is more accurate.

[0125] Of course, the two test pieces 1283 corresponding to each monitoring chain 1281 can also be located at opposite ends of the monitoring chain 1281, and the two test pieces 1283 corresponding to each monitoring chain 1281 are connected to the opposite ends of the monitoring chain 1281, that is, the jth monitoring layer of the first monitoring unit 12811 of the monitoring chain 1281 extends to the jth test layer of one of the two test pieces 1283 corresponding thereto, and the jth monitoring layer of the last monitoring unit 12811 of the monitoring chain 1281 extends to the jth test layer of the other test piece 1283 corresponding thereto, to realize the connection of the two test pieces 1283 corresponding thereto, where j is a positive integer less than or equal to N. In this way, the resistance value of each monitoring chain 1281 can be determined directly through the two test pieces 1283 corresponding to the monitoring chain 1281, without the need for a common test piece 1283.

[0126] It should be noted that the width of the monitoring chain 1281 and / or the spacing between adjacent two monitoring chains 1281 can be changed according to actual conditions by those skilled in the art.

[0127] It should be noted that the test piece 1283 corresponding to the last monitoring chain 1281 can be located at the first end D1 of the monitoring chain 1281 (as shown in Figure 7 It should be noted that the test piece 1283 corresponding to the last monitoring chain 1281 can be located at the first end D1 of the monitoring chain 1281 (as shown in Figure 11 Figure 11 A structure diagram of another crack propagation monitoring structure provided by an embodiment of the present application is provided.

[0128] The specific structure of the crack propagation monitoring structure 128 provided by the embodiment of the present application is described above, and the crack propagation monitoring structure 128 can monitor different positions to which the crack propagates (i.e., detect different lengths of crack propagation). As known from the foregoing, a crack can be generated when the wafer 10 is cut, and the crack or delamination generated when the wafer 10 is cut can further propagate after subsequent temperature changes, that is, the crack will continue to increase in length based on the length when the wafer 10 is cut. For example, when the wafer 10 is cut, the crack does not reach the inside of the chip, but when the chip is applied to an electronic device, the crack will further propagate as the temperature of the chip changes during use, and can propagate to the inside of the chip, causing the chip to fail and affecting the performance of the electronic device using the chip.

[0129] Therefore, based on the above structure, an embodiment of the present application also provides a crack propagation monitoring method, which will be introduced below in combination with the crack propagation monitoring structure 128 shown in Figure 7

[0130] As shown in Figure 12 the crack propagation monitoring method can be implemented by the following steps:​​

[0131] S1, test the resistance value of the first monitoring chain 1281a on the wafer to be tested after the wafer is cut, wherein the wafer to be tested is the part of the wafer including the crack propagation monitoring structure 128 after the wafer is cut.

[0132] After the wafer is cut, the resistance value of the first monitoring chain 1281a is tested first to determine whether the crack generated when the wafer 10 is cut is at the position of the first monitoring chain 1281a. Specifically, when the resistance value of the first monitoring chain 1281a is measured to be very large, such as greater than a second preset value, wherein the second preset value can be 1 megaohm or the like, it is determined that the first monitoring chain 1281a is open circuit, that is, the crack has extended to the position of the first monitoring chain 1281a; when the resistance value of the first monitoring chain 1281a is measured to be very small, such as less than a first preset value, wherein the first preset value can be 100 ohms or 500 ohms or the like, it is determined that the first monitoring chain 1281a is not open circuit, that is, the crack has not extended to the position of the first monitoring chain 1281a.

[0133] For example, the four-terminal detection technology can be used to test the resistance value of the first monitoring chain 1281a on the wafer to be tested. Of course, the four-terminal detection technology can also be used to test the resistance value of other monitoring chains 1281 (such as the second monitoring chain 1281b, the third monitoring chain 1281c, the fourth monitoring chain 1281d, etc.) on the wafer to be tested.

[0134] S2, determine whether the resistance value of the first monitoring chain 1281a is abnormal, if yes, execute step S3; if no, execute step S6.

[0135] The resistance value of the first monitoring chain 1281a is very large, that is, the resistance value of the first monitoring chain 1281a is abnormal, for example, the resistance value of the first monitoring chain 1281a is greater than the second preset value described above. The resistance value of the first monitoring chain 1281a is very small, that is, the resistance value of the first monitoring chain 1281a is normal, for example, the resistance value of the first monitoring chain 1281a is less than the first preset value described above.

[0136] If the resistance value of the first monitoring chain 1281a is abnormal, it means that the crack generated when the wafer 10 is cut has extended to the position of the first monitoring chain 1281a, and at this time the specific position of the crack propagation cannot be determined.

[0137] If the resistance value of the first monitoring chain 1281a is normal, it means that the crack generated when the wafer 10 is cut has not extended to the position of the first monitoring chain 1281a, and the wafer to be tested can be placed in a test environment for temperature cycle test to determine the change rule of the crack propagation length and the number of temperature cycles.

[0138] S3, starting from the second monitoring chain 1281b, each monitoring chain 1281 is taken as the current monitoring chain in turn for resistance value testing according to the monitoring chain arrangement order.

[0139] In order to determine the specific position of the crack propagation generated when the wafer 10 is cut, resistance value testing needs to be performed on other monitoring chains 1281 in turn according to the monitoring chain arrangement order (the first monitoring chain 1281a, the second monitoring chain 1281b, the third monitoring chain 1281c, the fourth monitoring chain 1281d, and other monitoring chains arranged in turn). Since the first monitoring chain 1281a has been tested, testing needs to start from the second monitoring chain 1281b at this time.

[0140] S4, judging whether the resistance value of the current monitoring chain is abnormal, if yes, step S3 is continued until the resistance values of all monitoring chains are tested; if no, step S5 is executed.

[0141] If the current monitoring chain is the second monitoring chain 1281b, and the resistance value of the second monitoring chain 1281b is abnormal, it indicates that the crack has propagated to the position of the second monitoring chain 1281b. At this time, it cannot be determined whether the crack has propagated to the third monitoring chain 1281c, so the third monitoring chain 1281c needs to be taken as the current monitoring chain for resistance value testing, and the same is true for other monitoring chains.

[0142] For example, still taking the example that the plurality of monitoring chains 1281 include the first monitoring chain 1281a, the second monitoring chain 1281b, the third monitoring chain 1281c, the fourth monitoring chain 1281d and the fifth monitoring chain 1281e, and the distances from the first monitoring chain 1281a, the second monitoring chain 1281b, the third monitoring chain 1281c, the fourth monitoring chain 1281d and the fifth monitoring chain 1281e to the cutting path 12b are increasingly far apart, if the resistance value of the first monitoring chain 1281a is greater than the second preset value, it indicates that the first monitoring chain 1281a is broken, and the resistance value of the second monitoring chain 1281b (the current monitoring chain at this time) is tested; if the resistance value of the second monitoring chain 1281b is also greater than the second preset value, it indicates that the second monitoring chain 1281b is also broken, and the resistance value of the third monitoring chain 1281c (the current monitoring chain at this time) is tested; if the resistance value of the third monitoring chain 1281c is also greater than the second preset value, it indicates that the third monitoring chain 1281c is also broken, and the resistance value of the fourth monitoring chain 1281d (the current monitoring chain at this time) is tested; if the resistance value of the fourth monitoring chain 1281d is also greater than the second preset value, it indicates that the fourth monitoring chain 1281d is also broken, and the resistance value of the fifth monitoring chain 1281e (the current monitoring chain at this time) is tested; if the resistance value of the fifth monitoring chain 1281e is also greater than the second preset value, it indicates that the fifth monitoring chain 1281e is also broken, and further indicates that the crack generated when the wafer 10 is cut has expanded to the position where the fifth monitoring chain 1281e is located. For example, the distance from the fifth monitoring chain 1281e to the cutting path 12b is 12 μm, which indicates that the length of the crack generated when the wafer 10 is cut is 12 μm, which will affect the functional area of the chip, and therefore the chip cannot be applied to electronic devices.

[0143] It should be noted that the following examples also take the example that the plurality of monitoring chains 1281 include the first monitoring chain 1281a, the second monitoring chain 1281b, the third monitoring chain 1281c, the fourth monitoring chain 1281d and the fifth monitoring chain 1281e, and the distances from the first monitoring chain 1281a, the second monitoring chain 1281b, the third monitoring chain 1281c, the fourth monitoring chain 1281d and the fifth monitoring chain 1281e to the cutting path 12b are increasingly far apart, and the following examples will not be described again.

[0144] S5, determining the length of the position of the previous monitoring chain 1281 of the current monitoring chain 1281 as the length of the crack generated when the wafer 10 is cut, and then performing step S6.

[0145] If the resistance of the current monitoring chain is normal, it indicates that the crack has not extended to the position of the current monitoring chain 1281, but to the position of the previous monitoring chain 1281 of the current monitoring chain, and the length of the crack at the position of the previous monitoring chain 1281 when the wafer 10 is cut is determined as the length of the crack generated when the wafer 10 is cut, which is referred to as the initial crack length, i.e., L0 in the following.

[0146] It can be understood that if the crack generated when the wafer 10 is cut does not extend to the position of the first monitoring chain 1281a, the actual length of the crack can be determined by measurement or the like, and the length of the crack at this time is referred to as the initial crack length, i.e., L0 in the following; or the length of the crack can be directly set as a fixed value, which can be 0.5 μm, and the fixed value can be referred to as the initial crack length, i.e., L0 in the following; since the crack extension monitoring structure 128 is generally very close to the cutting groove 12b, the initial crack length L0 can also be directly set as 0 μm.

[0147] For example, if the resistance of the second monitoring chain 1281b is less than the first preset value, it indicates that the second monitoring chain 1281b is not broken, and further indicates that the crack extends to the position of the first monitoring chain 1281a, but does not extend to the position of the second monitoring chain 1281b, and the length of the crack at the position of the previous monitoring chain (i.e., the first monitoring chain 1281a) of the second monitoring chain 1281b is determined.

[0148] S6, placing the wafer to be tested in a test environment to perform a temperature cycle experiment, and determining the change rule of the crack extension length and the number of temperature cycles.

[0149] Because after the wafer 10 is cut, subsequent packaging processes are required to form a chip, and the chip will be applied to an electronic device, and the chip will generate temperature changes when it performs its functions in the electronic device, and the temperature changes of the chip will further extend the crack generated when the wafer is cut, so the temperature cycle experiment needs to be performed on the wafer to be tested to determine whether the crack generated when the wafer is cut will extend to the inside of the chip (i.e., the functional area of the chip) during the use of the chip.

[0150] That is, after the wafer 10 is cut, as long as not all monitoring chains 1281 are broken before the temperature cycle experiment, the temperature cycle experiment needs to be performed on the wafer to be tested.

[0151] The temperature cycle experiment is to place the wafer to be tested in a test environment with high and low temperature changes for a predetermined number of temperature cycles. The high and low temperature changes are to increase the temperature in a step-by-step manner from a predetermined minimum temperature to a predetermined maximum temperature within a predetermined time. One high and low temperature change is one temperature cycle, and a predetermined number of temperature cycles is to increase the temperature in a step-by-step manner from a predetermined minimum temperature to a predetermined maximum temperature within a predetermined time, and then repeat the cycle for a predetermined number of times.

[0152] For example, the high and low temperature changes can be -55°C to 125°C, i.e. the predetermined minimum temperature is -55°C, and the predetermined maximum temperature is 125°C, i.e. the temperature is increased in a step-by-step manner from -55°C to 125°C within a predetermined time.

[0153] For example, the predetermined number of temperature cycles can be 500, 700, 1000, 1250, 1400, 1500, 1750, or 2000, etc.

[0154] That is, the wafer to be tested is placed in a test environment of -55°C to 125°C, and then 500 temperature cycles are performed, i.e. the temperature is increased in a step-by-step manner from -55°C to 125°C, and this cycle is executed 500 times; 700 temperature cycles are performed, i.e. the temperature is increased in a step-by-step manner from -55°C to 125°C, and this cycle is executed 700 times; 1000 temperature cycles are performed, i.e. the temperature is increased in a step-by-step manner from -55°C to 125°C, and this cycle is executed 1000 times; 1250 temperature cycles are performed, i.e. the temperature is increased in a step-by-step manner from -55°C to 125°C, and this cycle is executed 1250 times; 1400 temperature cycles are performed, i.e. the temperature is increased in a step-by-step manner from -55°C to 125°C, and this cycle is executed 1400 times; 1500 temperature cycles are performed, i.e. the temperature is increased in a step-by-step manner from -55°C to 125°C, and this cycle is executed 1500 times; 1750 temperature cycles are performed, i.e. the temperature is increased in a step-by-step manner from -55°C to 125°C, and this cycle is executed 1750 times; and 2000 temperature cycles are performed, i.e. the temperature is increased in a step-by-step manner from -55°C to 125°C, and this cycle is executed 2000 times. Based on this, the variation law of crack propagation length and temperature cycle number is derived to facilitate subsequent reliability evaluation, for example, a crack propagation model of the interconnection medium layer of the wafer can be established to facilitate subsequent risk evaluation. Figure 13As shown, the wafer to be tested is placed in a test environment for temperature cycle experiments to determine the specific steps of the change rule of crack propagation length and temperature cycle number:

[0155] S21, place the wafer to be tested in the test environment for a first preset number of temperature cycles, wherein the first preset number of temperature cycles is the minimum preset number of temperature cycles.

[0156] The fewer the number of temperature cycles, the smaller the length of the further crack propagation, so the wafer to be tested is first subjected to a minimum preset number of temperature cycles.

[0157] For example, the preset number of temperature cycles includes 500, 700, 1000, 1250, 1400, 1500, 1750 and 2000 temperature cycles, and the first preset number of temperature cycles is 500 temperature cycles.

[0158] S22, determine whether the resistance of the preset monitoring chain is abnormal, if yes, execute step S23; if no, execute step S26, wherein the preset monitoring chain is the monitoring chain 1281 that is not broken and has the smallest distance from the cutting path 12b before the temperature cycle experiment after the wafer 10 is cut.

[0159] If the crack generated when the wafer 10 is cut does not extend to the position of the first monitoring chain 1281a, the preset monitoring chain is the first monitoring chain 1281a; if the crack generated when the wafer 10 is cut has extended to the second monitoring chain 1281b but not to the position of the third monitoring chain 1281c, the preset monitoring chain is the third monitoring chain 1281c.

[0160] After the wafer to be tested is subjected to a minimum preset number of temperature cycles (such as 500 temperature cycles) in the test environment, it is determined whether the crack has extended to the position of the preset monitoring chain. Specifically, it can be determined whether the preset monitoring chain has been broken based on the resistance of the preset monitoring chain. More specifically, when the resistance of the preset monitoring chain is measured to be very large, such as greater than a second preset value, wherein the second preset value can be 1 megaohm or the like, it is determined that the preset monitoring chain is broken, i.e. the crack has extended to the position of the preset monitoring chain; when the resistance of the preset monitoring chain is measured to be very small, such as less than a first preset value, wherein the first preset value can be 100 ohms or 500 ohms or the like, it is determined that the preset monitoring chain is not broken.

[0161] S23, starting from the next monitoring chain of the preset monitoring chain, each monitoring chain 1281 is tested as the current monitoring chain in order according to the monitoring chain arrangement order.

[0162] If the resistance of the preset monitoring chain is abnormal, it indicates that the crack has expanded to the position of the preset monitoring chain under the action of the first preset number of temperature cycles, and the specific position of the crack expansion cannot be determined at this time, so the resistance test needs to be performed on other monitoring chains 1281 in sequence according to the monitoring chain arrangement order (the first monitoring chain 1281a, the second monitoring chain 1281b, the third monitoring chain 1281c, the fourth monitoring chain 1281d, and the like) to determine the specific position of the crack expansion under the first preset number of temperature cycles. Since the preset monitoring chain has been tested in the previous step, the next monitoring chain of the preset monitoring chain needs to be tested at this time.

[0163] For example, if the preset monitoring chain is the first monitoring chain 1281a, the next monitoring chain of the preset monitoring chain is the second monitoring chain 1281b; if the preset monitoring chain is the third monitoring chain 1281c, the next monitoring chain of the preset monitoring chain is the fourth monitoring chain 1281d.

[0164] S24, judge whether the resistance of the current monitoring chain is abnormal, if yes, continue to execute step S23 until the resistance of all monitoring chains is tested; if no, execute step S25.

[0165] If the current monitoring chain is the second monitoring chain 1281b, and the resistance of the second monitoring chain 1281b is abnormal, it indicates that the crack has expanded to the position of the second monitoring chain 1281b, and it cannot be determined at this time whether the crack has expanded to the third monitoring chain 1281c, so the resistance test needs to be performed on the third monitoring chain 1281c as the current monitoring chain, and the like.

[0166] For example, if the resistance of the first monitoring chain 1281a is greater than the second preset value, it indicates that the first monitoring chain 1281a is broken, and the resistance of the second monitoring chain 1281b (the current monitoring chain at this time) needs to be tested; if the resistance of the second monitoring chain 1281b is also greater than the second preset value, it indicates that the second monitoring chain 1281b is also broken, and the resistance of the third monitoring chain 1281c (the current monitoring chain at this time) needs to be tested; if the resistance of the third monitoring chain 1281c is also greater than the second preset value, it indicates that the third monitoring chain 1281c is also broken, and the resistance of the fourth monitoring chain 1281d (the current monitoring chain at this time) needs to be tested; if the resistance of the fourth monitoring chain 1281d is also greater than the second preset value, it indicates that the fourth monitoring chain 1281d is also broken, and the resistance of the fifth monitoring chain 1281e (the current monitoring chain at this time) needs to be tested; if the resistance of the fifth monitoring chain 1281e is also greater than the second preset value, it indicates that the fifth monitoring chain 1281e is also broken, and it further indicates that the crack will expand to the position of the fifth monitoring chain 1281e under a smaller number of temperature cycles (such as 500 times of temperature cycles).

[0167] S25, determine the length of the crack at the position of the previous monitoring chain 1281 of the current monitoring chain 1281 under the first preset number of temperature cycles.

[0168] If the resistance value of the current monitoring chain is normal, it indicates that the crack has not expanded to the position of the monitoring chain 1281 with normal resistance value, but has expanded to the position of the previous monitoring chain 1281 with normal resistance value, and then the length of the crack at the position of the previous monitoring chain 1281 under the first preset number of temperature cycles is determined.

[0169] For example, if the resistance value of the second monitoring chain 1281b is less than the first preset value, it indicates that the second monitoring chain 1281b is not broken, and further indicates that the crack has expanded to the position of the first monitoring chain 1281a, but has not expanded to the position of the second monitoring chain 1281b, and then the length of the crack at the position of the previous monitoring chain (i.e. the first monitoring chain 1281a) of the second monitoring chain 1281b under the first preset number of temperature cycles is determined.

[0170] For example, if the resistance value of the second monitoring chain 1281b is also greater than the second preset value, it indicates that the second monitoring chain 1281b is also broken, and the resistance value of the third monitoring chain 1281c (the current monitoring chain at this time) is tested, if the resistance value of the third monitoring chain 1281c is less than the first preset value, it indicates that the third monitoring chain 1281c is not broken, and further indicates that the crack has expanded to the position of the second monitoring chain 1281b, but has not expanded to the position of the third monitoring chain 1281c, and then the length of the crack at the position of the previous monitoring chain (i.e. the second monitoring chain 1281b) of the third monitoring chain 1281c under the first preset number of temperature cycles is determined.

[0171] S26, from the second preset number of temperature cycles, each temperature cycle number is taken as the current temperature cycle number in turn according to the temperature cycle number arrangement order, and the temperature cycle numbers are increased in turn.

[0172] If the crack of the wafer to be tested does not expand to the preset monitoring chain under the first preset number of temperature cycles, the number of temperature cycles needs to be increased. The number of cycles can be arranged in ascending order of the preset number of temperature cycles, such as 500, 700, 1000, 1250, 1400, 1500, 1750, and 2000. That is, the first preset number of temperature cycles is 500, the second preset number of temperature cycles is 700, the third preset number of temperature cycles is 1000, the fourth preset number of temperature cycles is 1250, the fifth preset number of temperature cycles is 1400, the sixth preset number of temperature cycles is 1500, the seventh preset number of temperature cycles is 1750, and the eighth preset number of temperature cycles is 2000.

[0173] S27, judge whether the resistance value of the preset monitoring chain is abnormal under the current number of temperature cycles. If not, continue to execute step S26 until all the numbers of temperature cycles are tested; if yes, execute step S28.

[0174] If the current number of temperature cycles is the second preset number, and the resistance value of the preset monitoring chain a is normal, it indicates that the crack of the wafer to be tested has not expanded to the preset monitoring chain 1281a, and the number of temperature cycles needs to be increased, that is, the third preset number is taken as the current number of temperature cycles, and the same is true for the subsequent numbers.

[0175] For example, if the current temperature cycle number is the second preset number and the resistance of the preset monitoring chain is normal, it indicates that the crack of the wafer to be tested has not extended to the position of the preset monitoring chain. Then, the wafer to be tested is subjected to the second preset number of temperature cycles (the current temperature cycle number at this time), such as 700 temperature cycles. If the resistance of the preset monitoring chain is still less than the first preset value, it indicates that the preset monitoring chain is still not broken, and thus it indicates that the crack of the wafer to be tested has not extended to the position of the preset monitoring chain when the wafer to be tested is subjected to the second preset number of temperature cycles in the test environment. Then, the wafer to be tested is subjected to the third preset number of temperature cycles (the current temperature cycle number at this time), such as 1000 temperature cycles. If the resistance of the preset monitoring chain is still less than the first preset value, it indicates that the preset monitoring chain is still not broken, and thus it indicates that the crack of the wafer to be tested has not extended to the position of the preset monitoring chain when the wafer to be tested is subjected to the third preset number of temperature cycles in the test environment. Then, the wafer to be tested is subjected to the fourth preset number of temperature cycles (the current temperature cycle number at this time), such as 1250 temperature cycles. If the resistance of the preset monitoring chain is still less than the first preset value, it indicates that the preset monitoring chain is still not broken, and thus it indicates that the crack of the wafer to be tested has not extended to the position of the preset monitoring chain when the wafer to be tested is subjected to the fourth preset number of temperature cycles in the test environment. Then, the wafer to be tested is subjected to the fifth preset number of temperature cycles (the current temperature cycle number at this time), such as 1400 temperature cycles. If the resistance of the preset monitoring chain is still less than the first preset value, it indicates that the preset monitoring chain is still not broken, and thus it indicates that the crack of the wafer to be tested has not extended to the position of the first monitoring chain when the wafer to be tested is subjected to the fifth preset number of temperature cycles in the test environment. Then, the wafer to be tested is subjected to the sixth preset number of temperature cycles (the current temperature cycle number at this time), such as 1400 temperature cycles. If the resistance of the preset monitoring chain is still less than the first preset value, it indicates that the preset monitoring chain is still not broken, and thus it indicates that the crack of the wafer to be tested has not extended to the position of the first monitoring chain when the wafer to be tested is subjected to the sixth preset number of temperature cycles in the test environment. Then, the wafer to be tested is subjected to the sixth preset number of temperature cycles (the current temperature cycle number at this time), such as 1500 temperature cycles. If the resistance of the preset monitoring chain is still less than the first preset value, it indicates that the preset monitoring chain is still not broken, and thus it indicates that the crack of the wafer to be tested has not extended to the position of the first monitoring chain when the wafer to be tested is subjected to the sixth preset number of temperature cycles in the test environment. Then, the wafer to be tested is subjected to the seventh preset number of temperature cycles (the current temperature cycle number at this time), such as 1750 temperature cycles. If the resistance of the preset monitoring chain is still less than the first preset value, it indicates that the preset monitoring chain is still not broken, and thus it indicates that the crack of the wafer to be tested has not extended to the position of the preset monitoring chain when the wafer to be tested is subjected to the seventh preset number of temperature cycles in the test environment.Then the eighth preset number of temperature cycles (the current number of temperature cycles at this time) are performed on the wafer under test, such as 2000 temperature cycles. If the resistance of the preset monitoring chain is still less than the first preset value, it indicates that the preset monitoring chain has not been broken, and thus the crack has not expanded to the position of the preset monitoring chain when the wafer under test is placed in the test environment for the eighth preset number of temperature cycles. That is, after the wafer under test is placed in the test environment for all preset numbers of temperature cycles, the crack has not expanded to the position of the preset monitoring chain, indicating that the wafer under test has no crack expansion during the temperature cycle test, and the chip is safe and can be used in electronic equipment.

[0176] S28, starting from the next monitoring chain of the preset monitoring chain, each monitoring chain is sequentially taken as the current monitoring chain for resistance testing according to the monitoring chain arrangement order.

[0177] If the resistance of the preset monitoring chain is abnormal, it indicates that the crack has expanded to the position of the preset monitoring chain. At this time, the specific position of the crack expansion cannot be determined, so resistance testing needs to be performed on other monitoring chains 1281 according to the monitoring chain arrangement order (the first monitoring chain 1281a, the second monitoring chain 1281b, the third monitoring chain 1281c, the fourth monitoring chain 1281d, and other monitoring chains are sequentially arranged) to determine the specific position of the crack expansion. Since the preset monitoring chain is abnormal, the next monitoring chain of the preset monitoring chain needs to be tested at this time.

[0178] S29, judging whether the resistance of the current monitoring chain is abnormal. If yes, step S28 is continued until the resistance of all monitoring chains is tested. If no, step S30 is performed.

[0179] If the current monitoring chain is the second monitoring chain 1281b and the resistance of the second monitoring chain 1281b is abnormal, it indicates that the crack has expanded to the position of the second monitoring chain 1281b. At this time, it cannot be determined whether the crack has expanded to the third monitoring chain 1281c, so the third monitoring chain 1281c needs to be taken as the current monitoring chain for resistance testing, and the same is true for the other monitoring chains.

[0180] For example, if the resistance of the first monitoring chain 1281a is greater than the second preset value, it indicates that the first monitoring chain 1281a is broken, and it is necessary to determine the specific position of the crack propagation under the current temperature cycle number, for example, to continue testing the resistance of the second monitoring chain (the current monitoring chain at this time) 1281b; if the resistance of the second monitoring chain 1281b is also greater than the second preset value, it indicates that the second monitoring chain 1281b is also broken, and it is necessary to continue testing the resistance of the third monitoring chain (the current monitoring chain at this time) 1281c; if the resistance of the third monitoring chain 1281c is also greater than the second preset value, it indicates that the third monitoring chain 1281c is also broken, and it is necessary to continue testing the resistance of the fourth monitoring chain (the current monitoring chain at this time) 1281d; if the resistance of the fourth monitoring chain 1281d is also greater than the second preset value, it indicates that the fourth monitoring chain 1281d is also broken, and it is necessary to continue testing the resistance of the fifth monitoring chain (the current monitoring chain at this time) 1281e; if the resistance of the fifth monitoring chain 1281e is also greater than the second preset value, it indicates that the fifth monitoring chain 1281e is also broken, and it further indicates that the wafer under test will expand to the position of the fifth monitoring chain 1281e under the second preset number of temperature cycles.

[0181] S30, determining that the length of the position of the previous monitoring chain of the current monitoring chain is the length of the crack under the current temperature cycle number.

[0182] If the resistance of the current monitoring chain is normal, it indicates that the crack has not expanded to the position of the monitoring chain 1281 with normal resistance, but has expanded to the position of the previous monitoring chain 1281 of the monitoring chain 1281 with normal resistance, and it is determined that the length of the position of the previous monitoring chain 1281 is the length of the crack under the current temperature cycle number.

[0183] For example, when the wafer under test is placed in the test environment for the second preset number of temperature cycles, the resistance of the first monitoring chain 1281a is greater than the second preset value, which indicates that the first monitoring chain 1281a is broken, and it further indicates that the crack expands to the position of the first monitoring chain 1281a when the wafer under test is placed in the test environment for the second preset number of temperature cycles, and it is necessary to further determine the specific position of the crack propagation under the current temperature cycle number, for example, to continue testing the resistance of the second monitoring chain (the current monitoring chain at this time) 1281b; if the resistance of the second monitoring chain 1281b is still greater than the second preset value, it indicates that the second monitoring chain 1281b is broken, and it is necessary to continue testing the resistance of the third monitoring chain (the current monitoring chain at this time) 1281c; if the resistance of the third monitoring chain 1281c is less than the first preset value, it indicates that the third monitoring chain 1281c is not broken, and it is determined that the length of the position of the previous monitoring chain (i.e., the second monitoring chain 1281b) of the third monitoring chain 1281c is the length of the crack under the second preset number of temperature cycles.

[0184] S31, if there are still monitoring chains unbroken, then the wafer to be tested is subjected to the next preset number of temperature cycles of the current temperature cycle number, the length of the crack under the next preset number of temperature cycles is determined, until all monitoring chains are completely broken or all temperature cycle numbers are completely tested.

[0185] For example, if step S30 determines that the length of the second monitoring chain 1281b is the length of the crack under the second preset number of temperature cycles (such as 700 times). Then the monitoring chains after the second monitoring chain 1281b are all unbroken, then the temperature cycle number can be increased, such as to 1000 times, if the crack under 1000 times of temperature cycle extends to the third monitoring chain 1281c, that is, the resistance value of the third monitoring chain 1281c is abnormal and the resistance value of the fourth monitoring chain 1281d is normal, then the length of the third monitoring chain 1281c is determined as the length of the crack under the third preset number of temperature cycles. At this time, there are still monitoring chains 1281 unbroken (the fourth monitoring chain 1281d and the fifth monitoring chain 1281e are unbroken), so the temperature cycle number is increased, such as to 1250 times, if the crack under 1250 times of temperature cycle extends to the fourth monitoring chain 1281d, that is, the resistance value of the fourth monitoring chain 1281d is abnormal and the resistance value of the fifth monitoring chain 1281e is normal, then the length of the fourth monitoring chain 1281d is determined as the length of the crack under the fourth preset number of temperature cycles. Until all monitoring chains are completely broken or all temperature cycle numbers are completely tested.

[0186] In summary, after the wafer 10 is cut, the resistance value of the monitoring chain 1281 is tested before the temperature cycle experiment, and the length generated when the wafer 10 is cut is determined. As long as not all monitoring chains 1281 are broken, the crack will be subjected to a temperature cycle experiment. When the wafer to be tested is subjected to a temperature cycle experiment, the wafer to be tested is first placed in a test environment for a first preset number of temperature cycles, and the position of crack propagation under the temperature cycle number is determined. Then the temperature cycle number is increased, such as the second preset number of temperature cycles, and the position of crack propagation under the temperature cycle number is determined. Then the temperature cycle number is increased, such as the third preset number of temperature cycles, and the position of crack propagation under the temperature cycle number is determined. In turn, the length of the crack corresponding to each temperature cycle number is determined, and the corresponding relationship between the crack length and the temperature cycle number is determined. For example, when the crack is 1 μm, 2 μm, 3 μm, 4 μm, 5 μm, 6 μm, and 7 μm, the temperature cycle number is 700, 1000, 1250, 1400, 1500, 1750, and 2000 respectively. The value is brought into the crack propagation formula:

[0187] L 裂纹 = L0 + C x F m

[0188] wherein, L 裂纹 is the length of the crack when the temperature cycle experiment is performed, L0 is the length of the crack initially generated when the wafer 10 is cut, F is the number of times of temperature cycles when the temperature cycle experiment is performed, and C and m are constants. The specific values of C and m are obtained, and then the variation rule of the crack propagation length in the wafer with the number of times of temperature cycles can be obtained, so as to realize real-time monitoring of the crack propagation state of the interconnection medium layer 12.

[0189] In an application scenario, the chip formed after the wafer is cut has a micro crack, and the distance between the crack and the functional area of the chip is, for example, 8 μm. The 8 μm is brought into the L 裂纹 = L0 + CxF m to obtain the corresponding number of times of temperature cycles, so as to evaluate whether the number of times of temperature cycles meets the use requirement in the electronic device using the chip.

[0190] In summary, through the crack propagation monitoring structure 128 and by using the crack propagation monitoring method, the relationship between the crack propagation length and the number of times of temperature cycles can be derived, so as to facilitate the reliability evaluation of the product.

[0191] The above-described embodiments are merely used to illustrate the technical solutions of the present application, but not to limit the present application; even though the present application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that the technical solutions recorded in the foregoing embodiments can be modified, or some technical features thereof can be replaced by equivalent technical features; and these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present application.

Claims

1. A crack propagation monitoring structure, characterized in that, include: Multiple monitoring chains arranged along a first direction and extending along a second direction, wherein the first direction and the second direction intersect; Multiple test pieces; each of the monitoring chains corresponds to at least one of the test pieces and is connected to at least one of the test pieces; the test piece is used to determine whether the monitoring chain connected to the test piece has an open circuit, so as to determine the location of crack propagation.

2. The crack propagation monitoring structure according to claim 1, characterized in that, Along the second direction, each monitoring chain includes multiple monitoring units spaced apart; each monitoring chain also includes a first connecting unit and a second connecting unit. Within the same monitoring chain, except for the first and last monitoring units, the other monitoring units are connected to monitoring units located on both sides of the monitoring unit through the first connecting unit and the second connecting unit, respectively.

3. The crack propagation monitoring structure according to claim 2, characterized in that, The monitoring unit comprises N monitoring layers stacked together, with adjacent monitoring layers interconnected, where N is a positive integer greater than or equal to 2; The Nth monitoring layer includes a first monitoring layer, ..., and an Nth monitoring layer. The first connection unit and the first monitoring layer are configured on the same layer, and the second connection unit and the Nth monitoring layer are configured on the same layer.

4. The crack propagation monitoring structure according to any one of claims 1-3, characterized in that, The crack propagation monitoring structure also includes multiple connectors for connecting two adjacent monitoring chains.

5. The crack propagation monitoring structure according to claim 4, characterized in that, Except for the first and last monitoring chains, along the second direction, the opposite ends of the other monitoring chains are connected to the monitoring chains located on both sides of the monitoring chain by the two connectors respectively.

6. The crack propagation monitoring structure according to claim 4, characterized in that, The connector includes at least one connection layer, which is formed using the same semiconductor process as the monitoring layer.

7. The crack propagation monitoring structure according to claim 3, characterized in that, The test piece includes N test layers; The j-th monitoring layer of the monitoring unit located at the end of the monitoring chain extends to the j-th test layer of the test piece corresponding to the monitoring chain, so as to connect with the test piece, where j is a positive integer less than or equal to N.

8. The crack propagation monitoring structure according to claim 7, characterized in that, The N-layer test layer and the N-layer monitoring layer are formed using the same semiconductor process.

9. The crack propagation monitoring structure according to claim 3, characterized in that, Each monitoring chain corresponds to two test pieces, and the two test pieces are located at a preset end of the monitoring chain, which is the end of the monitoring chain that is not connected to the next monitoring chain. The j-th monitoring layer of the monitoring unit at the preset end extends to the j-th test layer of the two test pieces to connect with the two test pieces, where j is a positive integer less than or equal to N.

10. The crack propagation monitoring structure according to any one of claims 1-9, characterized in that, The size of the monitoring chain in the first direction is W1, where W1 is less than or equal to 2 μm and greater than or equal to 0.5 μm.

11. The crack propagation monitoring structure according to any one of claims 1-10, characterized in that, The distance between two adjacent monitoring chains in the first direction is W2, where W2 is less than or equal to 2 μm and greater than or equal to 0.5 μm.

12. The crack propagation monitoring structure according to any one of claims 1-11, characterized in that, The width of the crack propagation monitoring structure is W3, which is greater than or equal to 5 μm and less than or equal to 10 μm.

13. A wafer, characterized in that, include: The crack propagation monitoring structure according to any one of claims 1-12.

14. The wafer according to claim 13, characterized in that, include: Substrate; An interconnect dielectric layer is disposed on one side of the substrate and includes a plurality of spaced chip placement areas, with a dicing channel formed between two adjacent chip placement areas. It also includes at least one crack propagation monitoring area located on at least one side of the dicing channel, and the crack propagation monitoring structure is disposed in the crack propagation monitoring area.

15. The wafer according to claim 14, characterized in that, The distance between the first monitoring chain of the crack propagation monitoring structure and the cutting channel is H1, where H1 is greater than or equal to 0.5 μm and less than or equal to 2 μm. The first monitoring chain is the monitoring chain with the smallest distance to the cutting channel among the multiple monitoring chains.

16. The wafer according to claim 14, characterized in that, The distance between the last monitoring chain of the crack propagation monitoring structure and the cutting channel is H2, where H2 is greater than or equal to 5.5 μm and less than or equal to 12 μm. The last monitoring chain is the monitoring chain with the largest distance from the cutting channel among the multiple monitoring chains.

17. A method for monitoring crack propagation, characterized in that, Applied to a wafer as described in any one of claims 13-15, the crack propagation monitoring method comprises: After the wafer is diced, the resistance of the monitoring chain on the wafer to be tested is tested, wherein the wafer to be tested is the part of the wafer that includes the crack propagation monitoring structure after dicing; If the resistance of at least one of the multiple monitoring chains is less than the first preset value, the wafer to be tested is placed in a test environment for a temperature cycling experiment to determine the variation of crack propagation length and the number of temperature cycles.

18. The crack propagation monitoring method according to claim 17, characterized in that, If the resistance of at least one of the multiple monitoring chains is less than a first preset value, the wafer to be tested is placed in a test environment for a temperature cycling experiment to determine the variation patterns of crack propagation length and the number of temperature cycles, including: If the resistance of the first monitoring chain is less than the first preset value, the wafer to be tested is placed in the test environment for a temperature cycling experiment to determine the variation of crack propagation length and the number of temperature cycles. If the resistance of the first monitoring chain is greater than the second preset value, then starting from the second monitoring chain, each monitoring chain is tested sequentially as the current monitoring chain until the resistance of one of the monitoring chains is less than the first preset value. The length of the monitoring chain preceding the monitoring chain with the resistance less than the first preset value is determined as the length of the crack generated during wafer dicing. The wafer to be tested is placed in a test environment for temperature cycling experiments to determine the variation law of crack propagation length and the number of temperature cycles.

19. The crack propagation monitoring method according to claim 18, characterized in that, The wafer under test is placed in a test environment for temperature cycling experiments to determine the variation patterns of crack propagation length and the number of temperature cycles, including: The wafer to be tested is placed in a test environment and subjected to a first preset number of temperature cycles; If the resistance value of the preset monitoring chain is greater than the second preset value, then starting from the next monitoring chain of the preset monitoring chain, each monitoring chain is used as the current monitoring chain for resistance testing in the order of the monitoring chains, until the resistance value of the current monitoring chain is less than the first preset value. The length of the position of the previous monitoring chain of the current monitoring chain is determined as the length of the crack under the first preset number of temperature cycles. The preset monitoring chain is the monitoring chain that has not broken after the wafer is cut and has the smallest distance from the cutting position.

20. The crack propagation monitoring method according to claim 19, characterized in that, If the resistance of the preset monitoring chain is less than the first preset value, then starting from the second preset number of temperature cycles, each temperature cycle number is used as the current temperature cycle number for the experiment in the order of the temperature cycle number. The number of temperature cycles increases sequentially. The preset monitoring chain is the monitoring chain that is not broken after the wafer is cut and has the smallest distance from the cutting position. If the resistance of the preset monitoring chain is less than the first preset value at the current temperature cycle number, the process continues to execute the step of taking each temperature cycle number as the current temperature cycle number in the order of temperature cycle number until all temperature cycle numbers have been tested and the chip formed after wafer dicing is determined to be qualified.

21. The crack propagation monitoring method according to claim 20, characterized in that, If the resistance of the preset monitoring chain is greater than the second preset value at the current temperature cycle number, then starting from the next monitoring chain of the preset monitoring chain, each monitoring chain is used as the current monitoring chain for resistance testing in the order of the monitoring chains, until the resistance of the current monitoring chain is less than the first preset value, and the length of the previous monitoring chain is determined as the length of the crack at the current temperature cycle number.

22. The crack propagation monitoring method according to claim 21, characterized in that, The wafer under test is placed in a test environment for temperature cycling experiments to determine the variation patterns of crack propagation length and the number of temperature cycles, and the experiment also includes: The wafer to be tested is subjected to the next preset number of temperature cycles after the current temperature cycle number, and the length of the crack under the next preset number of temperature cycles is determined until all monitoring chains are broken or all temperature cycles are completed.

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