Monitoring structure for fusing influence of fuse wire

Abstract

The utility model relates to a structure for monitoring the fusing influence of a fuse wire, which comprises a plurality of groups of monitoring units, and the plurality of groups of monitoring units are arranged in the fusing process influence range of the fuse wire. The monitoring unit is connected with at least one target object; the target object comprises at least one structure of an active region layer, a polycrystalline silicon layer, a metal layer and a connecting hole layer. By the adoption of the monitoring structure, the health degree of the Fuse surrounding environment can be monitored in a multi-layer and multi-dimensional refined mode, and the influence range of Fuse upper and lower layer devices before and after the Fuse fusing process is comprehensively judged.

Description

Technical Field

[0001] The utility model belongs to the field of integrated circuit design and manufacturing, and in particular relates to a monitoring structure for the influence of a blown fuse. Background Art

[0002] Fuses have long been used to guide electronic signals within chips and are a key element in implementing repair technology. By exploiting the difference in resistance before and after a fuse blows, the original circuit connections are altered, allowing failed memory cells to be replaced with redundant cells. This repairs the failed memory cell array and improves chip yield. Traditional fuses come in three main types: metal fuses (which are blown with high current), polysilicon fuses (which are blown with high current), and laser fuses (which are blown with lasers).

[0003] Traditionally, most chip manufacturers have used laser-fuse technology, which involves emitting a laser of a specific energy and duration to melt the fuse. However, with the miniaturization of manufacturing processes, laser-fuses occupy a large amount of chip area, and their size cannot be reduced as process improvements are made. Furthermore, laser-fuses require specialized lasers and testing procedures, resulting in low production capacity and limiting their use.

[0004] The birth of the E-fuse stems from a discovery made by IBM engineers several years ago: Electron migration (EM) can be used to create much smaller fuse structures compared to older laser-fuse technology. EM fuses can be programmed on-chip, either during wafer probing or in the package. Using the on-chip voltage of the I / O circuit (typically 2.5V), a 10mA DC pulse lasting 200µs is sufficient to program a single fuse.

[0005] However, during the E-fuse blowing process, electromigration or localized explosions can affect the surrounding structures of the fuse, causing instability in the E-fuse process. Currently, no effective solution has been proposed to address the scope of the blown fuse and whether surrounding devices are damaged. Utility Model Content

[0006] In order to solve all or part of the problems in the prior art, the present invention provides a monitoring structure capable of testing and judging surrounding influences before and after a fuse is blown.

[0007] In order to achieve the above-mentioned object, the utility model provides a monitoring structure for the influence of a blown fusible link, comprising a plurality of monitoring units;

[0008] In the overlapping area and / or the surrounding area of ​​the fusible link, multiple groups of monitoring units are arranged;

[0009] At least one target object is connected to the monitoring unit;

[0010] The target object includes at least one structure of an active region layer, a polysilicon layer, a metal layer, and a connection hole layer.

[0011] In some embodiments, the fuse includes a first electrode, a second electrode, and a fuse connecting the first electrode and the second electrode;

[0012] The first electrode is larger than the second electrode;

[0013] The first electrode and the second electrode are a positive electrode and a negative electrode, respectively.

[0014] In some embodiments, the blowing process of the fuse includes the overlapping area and the peripheral area of ​​the fuse;

[0015] The overlapping region includes an overlapping region of the first electrode, the second electrode and / or the fuse;

[0016] The peripheral area includes a peripheral area within a first preset range of the first electrode, a peripheral area within a second preset range of the second electrode, and / or a peripheral area within a third preset range of the fuse.

[0017] In some embodiments, the target objects of the polysilicon layer and / or the target objects of the active region layer are arranged in the peripheral area according to a preset arrangement rule;

[0018] The target objects of the metal layer are arranged in the overlapping area and / or the peripheral area according to a preset arrangement rule;

[0019] The preset arrangement rule includes arrangement along the direction of the fuse wiring and / or arrangement perpendicular to the direction of the fuse wiring.

[0020] In some of these embodiments, the monitoring structure is a resistance testing structure;

[0021] At least one pin is provided at each end of the monitoring unit for connecting to test the resistance of the target object in the monitoring unit.

[0022] In some embodiments, the monitoring unit includes a target object, and at least one pin is provided at each end of the target object;

[0023] The monitoring unit includes at least two target objects, the at least two target objects are connected to form a chain structure through the structure of the connection hole layer and the metal layer, and at least one pin is provided at each end of the chain structure;

[0024] The target object is a structure in an active area layer, a polysilicon layer and / or a metal layer; and the connection hole layer includes a contact hole layer and / or a through hole layer.

[0025] In some embodiments, the monitoring structure is a capacitance test structure, and the capacitance test structure is formed based on two adjacent monitoring units;

[0026] The target objects in the two adjacent monitoring units are used as two electrodes of the capacitance test structure;

[0027] At least one pin is provided at one end of the monitoring unit for connecting the pins of two adjacent monitoring units to test the capacitance of the capacitance test structure.

[0028] In some of the embodiments, the monitoring unit includes a target object of a metal layer, set as a first target object;

[0029] The first target object is partially arranged around the fuse;

[0030] At least one pin is provided at one end of the first target object.

[0031] In some of the embodiments, the monitoring unit further includes at least one target object of the polysilicon layer and / or the active region layer, which is set as the second target object;

[0032] One end of the second target object is connected to the first target object through the structure of the connection hole layer and / or the metal layer to form the monitoring unit of the comb-shaped structure;

[0033] Wherein, the connection hole layer includes a contact hole layer and / or a through hole layer.

[0034] In some embodiments, the fuse is a polysilicon fuse, a metal fuse, or a laser fuse.

[0035] The monitoring structure for the impact of fuse blowing includes multiple groups of monitoring units arranged within the impact range of the fuse blowing process, and at least one target object is connected to the monitoring unit, and the target object includes at least one structure among the active area layer, polysilicon layer, metal layer and connection hole layer; it can realize multi-layer and multi-dimensional refined monitoring of the health of the environment around the fuse, comprehensively judge the impact range of the fuse upper and lower layer devices before and after the fuse blowing process, provide a basis for integrated circuit design and manufacturing, or give the health of the current E-fuse process development. BRIEF DESCRIPTION OF THE DRAWINGS

[0036] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the conventional technology, the following briefly introduces the drawings required for use in the embodiments or the conventional technology descriptions. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0037] Figure 1 A schematic diagram of a monitoring structure for the impact of a blown fuse in one embodiment;

[0038] Figure 2 A schematic diagram of a monitoring structure for the impact of a blown fuse in another embodiment;

[0039] Figure 3 This is a comparison diagram of a fuse before and after blowing in an embodiment. DETAILED DESCRIPTION

[0040] To facilitate understanding of the present application, the present application will be described more fully below with reference to the accompanying drawings. The accompanying drawings provide embodiments of the present application. However, the present application may be implemented in many different forms and is not limited to the embodiments described herein. Rather, these embodiments are provided to make the disclosure of the present application more thorough and comprehensive.

[0041] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as those commonly understood by those skilled in the art to which this application pertains. The terms used herein in the specification of this application are for the purpose of describing specific embodiments only and are not intended to limit this application.

[0042] It should be understood that when an element or layer is referred to as being "on," "adjacent," "connected to," or "coupled to" another element or layer, it can be directly on, adjacent to, connected to, or coupled to the other element or layer, or intervening elements or layers may be present. It should be understood that although the terms first, second, third, etc. may be used to describe various elements, components, regions, layers, doping types, and / or sections, these terms are merely used to distinguish one element, component, region, layer, doping type, or section from another element, component, region, layer, doping type, or section.

[0043] It should also be understood that the terms "include / comprising" or "having" etc. specify the presence of stated features, integers, steps, operations, components, parts or combinations thereof, but do not exclude the possibility of the presence or addition of one or more other features, integers, steps, operations, components, parts or combinations thereof. At the same time, in this specification, the term "and / or" includes any and all combinations of the relevant listed items.

[0044] Example 1

[0045] like Figure 1 As shown, a monitoring structure for the influence of fuse blowing is provided, including seven groups of monitoring units A, B, C, D, E, F, and G arranged within the influence range of the fuse blowing process. At least one target object is connected to the monitoring unit, and the target object includes at least one structure among the active area layer (AA), the polysilicon layer (Poly / MG), the metal layer (Metal 1), and the connection hole layer. In this embodiment, the connection hole layer refers to the contact hole layer (Contact), but in other embodiments, based on different application scenarios and design requirements, the connection hole layer can also be a through hole layer (Via) for connecting two metal layers, or even a structure including a contact hole layer and a through hole layer in a single monitoring unit to form a multi-layer structure. This application does not make specific limitations. Through the monitoring structure composed of the above seven groups of monitoring units, the status of these monitoring units is generally tested before the fuse blows, and then tested after the fuse blows. By comparing the status before and after the blow, the impact range of the blow can be inferred, and whether the surrounding devices are damaged after the fuse is programmed to blow. This can achieve multi-layer and multi-dimensional refined monitoring of the health of the fuse surrounding environment, and comprehensively judge the impact range of the fuse before and after the fuse blowing process on the upper and lower layer devices of the fuse, providing a basis for integrated circuit design and manufacturing, or indicating the health of the current E-fuse process development.

[0046] In this embodiment, the fuse is a polysilicon fuse (Poly Fuse), which includes a first electrode, a second electrode, and a fuse connecting the first electrode and the second electrode. The lower one is the first electrode, which is also the positive electrode, and the upper one is the second electrode, which is also the negative electrode. The negative electrode is larger than the positive electrode. The different shapes of the two electrodes can change the current density before entering the fuse. Combined with the setting of the positive and negative electrodes, it may affect the scope of subsequent melting. Figure 1 In the figure, for the convenience of explanation, the graphic structure of the polysilicon layer in the polysilicon fuse is drawn as an illustration, and the metal compound NiSi is formed in the subsequent process of the graphic structure.

[0047] The range of influence of the fuse's blowing process includes the overlapping area and the peripheral area of ​​the fuse. In this embodiment, the overlapping area is the overlapping area of ​​the fuse, and the peripheral area is the peripheral area within the third preset range of the fuse; this third preset range can be set according to the specific application scenario and requirements, and this application does not make specific restrictions. However, in other embodiments, depending on different application scenarios and requirements, the overlapping area can also be the overlapping area of ​​the first electrode, the second electrode and / or the fuse; the peripheral area can include the peripheral area within the first preset range of the first electrode, the peripheral area within the second preset range of the second electrode, and / or the peripheral area within the third preset range of the fuse; this application does not make specific restrictions.

[0048] like Figure 1 As shown, the target objects of the polysilicon layer and / or the target objects of the active area layer are arranged in the peripheral area according to a preset arrangement rule; the target objects of the metal layer are arranged in the overlapping area and / or the peripheral area according to a preset arrangement rule. The preset arrangement rule includes arrangement along the direction of the fuse wiring and / or arrangement perpendicular to the direction of the fuse wiring. Based on the specific application scenario and application requirements, the reasonable setting and arrangement of target objects and monitoring units can better infer the impact range of the fuse and the damage to surrounding devices after the fuse programming fuse is blown.

[0049] In this embodiment, the monitoring structure is a resistance test structure. Each monitoring unit is provided with a pin at each end for connecting to the resistance of the target object in the test monitoring unit. Specifically, a two-terminal method can be used to measure resistance. However, in other embodiments, two pins can be provided at each end of each monitoring unit to measure resistance using a four-terminal method for more accurate monitoring, depending on different application scenarios and application requirements. This application does not impose any specific limitations.

[0050] like Figure 1 As shown in the figure, the specific design of the seven monitoring units in the monitoring structure includes:

[0051] 1) Monitoring units A, B, C, and D each consist of two target objects, namely the active area layer (AA) or polysilicon layer (Poly / MG). The two target objects are connected via a contact layer and metal layer to form a chain structure. The two ends of the chain structure are connected through the contact layer and metal layer structure, each with a pin: Apin1 and Apin2 for monitoring unit A, Bpin1 and Bpin2 for monitoring unit B, Cpin1 and Cpin2 for monitoring unit C, and Dpin1 and Dpin2 for monitoring unit D. These four groups of active area layer (AA) or polysilicon layer monitoring units are arranged from farthest to closest based on the center position of the fuse (the center of the fuse link), with two pins in each group.

[0052] 2) Monitoring units E, F, and G each include a target object, or metal layer (Metal 1). A pin is located at each end of the target object: E pin 1 and E pin 2 for monitoring unit E, F pin 1 and F pin 2 for monitoring unit F, and G pin 1 and G pin 2 for monitoring unit G. These three sets of monitoring units on the metal layer are arranged from the outside inward based on the center of the fuse (the center of the fuse link), with two pins per set.

[0053] The testing method can be to apply high voltage to pin 1 and low voltage to pin 2 of each of the seven monitoring units AG, measure the current, and calculate the resistance. Based on this testing method, the change in resistance before and after the fuse blows can be used to determine whether the explosion caused a process impact. The failure status of monitoring units AD and EG can also be combined to determine the location of the explosion.

[0054] Example 2

[0055] Based on the application scenario of the first embodiment and based on the same solution idea, another monitoring structure design is provided to illustrate that the monitoring structure can be designed based on specific application scenarios and requirements.

[0056] like Figure 2 As shown in the figure, the specific design of the 11 monitoring units in the monitoring structure includes:

[0057] 1) Design five groups of monitoring units, each with a target object based on a metal layer (Metal 1) partially surrounding the fuse, also known as the first target object. Each monitoring unit's first target object has a pin at one end: AApin1, AApin2, AApin3, Polypin1, and Polypin2. Each of these five groups of monitoring units also has two second target objects; one end of the second target object is connected to the first target object via a contact layer (Contact), forming a comb-like monitoring unit structure. These five groups of monitoring units include:

[0058] Three groups of second target objects are monitoring units of target objects of the active area layer (AA). The second target objects of these three groups are arranged from the outside to the inside based on the center position of the fuse (the center of the fuse link), forming an AA comb (a monitoring unit with a comb structure);

[0059] The two groups of second target objects are monitoring units of the target object of the polysilicon layer (Poly / MG). The second target objects of the two groups are respectively arranged from the outside to the inside based on the center position of the fuse (the center of the fuse body) to form a Poly Comb (a monitoring unit with a comb structure).

[0060] In the monitoring unit of this embodiment, the two second target objects can be connected to the first target object of the metal layer (Metal 1) only through the structure of the contact hole layer (Contact). In other embodiments, the first target object and the second target object may need to be connected through the structure of the through hole layer, or may need to be connected through the structure of the contact hole layer and other metal layers, or may need to be connected through the structure of the through hole layer and other metal layers, or even need to be connected through the structure of the contact hole layer, the through hole layer and other metal layers to achieve connection. Based on different application scenarios and requirements, this is related to the layer selection of the first target object and the second target object in the specific embodiment and the structural design of the monitoring unit, and this application does not make specific limitations.

[0061] 2) Design six groups of monitoring units, each with only target objects based on the metal layer (Metal 1) partially surrounding the fuse link (except for the target object of one monitoring unit located in the overlapping area of ​​the fuse link, whose pin is Mpin1), i.e., the first target objects. The first target objects of these six groups of monitoring units are respectively arranged from near to far based on the center position of the fuse link (the center of the fuse link), and a pin is set at one end of the first target object of each monitoring unit: Mpin1, Mpin2, Mpin3, Mpin4, Mpin5, and Mpin6.

[0062] The testing method can be: using the monitoring units of two adjacent groups of AA / Poly pins as a capacitance test structure to measure capacitance; using the monitoring units of two adjacent groups of M pins as a capacitance test structure to measure capacitance. Based on this testing method, the change in capacitance before and after the fuse blows can be used to determine whether the explosion caused a process impact. The failure patterns between different AA / Poly pins and different M pins can also be combined to determine the location of the explosion.

[0063] It should be noted that in the above two embodiments, the fuse is a polysilicon fuse, but in other embodiments, the fuse may also be a metal fuse or a laser fuse. The position of the monitoring unit and the selection and connection method of the target objects at different layers can be specifically designed according to the structure and melting process of the specific fuse. This application does not make any specific restrictions.

[0064] Throughout this specification, references to terms such as "some embodiments," "other embodiments," and "desired embodiments" indicate that a particular feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of the present application. The schematic descriptions of these terms throughout this specification do not necessarily refer to the same embodiment or example.

[0065] The technical features of the above embodiments can be combined arbitrarily. To make the description concise, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0066] The above-described embodiments merely represent several implementation methods of the present application. While the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the present application. It should be noted that a person of ordinary skill in the art may make various modifications and improvements without departing from the spirit of the present application, and these modifications and improvements fall within the scope of protection of the present application. Therefore, the scope of protection of the present application shall be determined by the appended claims.

Claims

1. A monitoring structure for the influence of a blown fuse, characterized in that: Including multiple groups of monitoring units; In the overlapping area and / or the surrounding area of ​​the fusible link, multiple groups of monitoring units are arranged; At least one target object is connected to the monitoring unit; The target object includes at least one structure of an active region layer, a polysilicon layer, a metal layer, and a connection hole layer.

2. The monitoring structure according to claim 1, characterized in that: The fuse includes a first electrode, a second electrode, and a fuse connecting the first electrode and the second electrode; The first electrode is larger than the second electrode; The first electrode and the second electrode are a positive electrode and a negative electrode, respectively.

3. The monitoring structure according to claim 2, characterized in that: The influence range of the fusing process of the fuse includes the overlapping area and the peripheral area of ​​the fuse; The overlapping region includes an overlapping region of the first electrode, the second electrode and / or the fuse; The peripheral area includes a peripheral area within a first preset range of the first electrode, a peripheral area within a second preset range of the second electrode, and / or a peripheral area within a third preset range of the fuse.

4. The monitoring structure according to claim 3, characterized in that: The target objects of the polysilicon layer and / or the target objects of the active area layer are arranged in the peripheral area according to a preset arrangement rule; The target objects of the metal layer are arranged in the overlapping area and / or the peripheral area according to a preset arrangement rule; The preset arrangement rule includes arrangement along the direction of the fuse wiring and / or arrangement perpendicular to the direction of the fuse wiring.

5. The monitoring structure according to claim 4, characterized in that: The monitoring structure is a resistance testing structure; At least one pin is provided at each end of the monitoring unit for connecting to test the resistance of the target object in the monitoring unit.

6. The monitoring structure according to claim 5, characterized in that: The monitoring unit includes a target object, and at least one pin is provided at each end of the target object; The monitoring unit includes at least two target objects, the at least two target objects are connected to form a chain structure through the structure of the connection hole layer and the metal layer, and at least one pin is provided at each end of the chain structure; The target object is a structure in an active area layer, a polysilicon layer and / or a metal layer; and the connection hole layer includes a contact hole layer and / or a through hole layer.

7. The monitoring structure according to claim 4, characterized in that: The monitoring structure is a capacitance test structure, and the capacitance test structure is formed based on two adjacent monitoring units; The target objects in the two adjacent monitoring units are used as two electrodes of the capacitance test structure; At least one pin is provided at one end of the monitoring unit for connecting the pins of two adjacent monitoring units to test the capacitance of the capacitance test structure.

8. The monitoring structure according to claim 7, characterized in that: The monitoring unit includes a target object of the metal layer, which is set as a first target object; The first target object is partially arranged around the fuse; At least one pin is provided at one end of the first target object.

9. The monitoring structure according to claim 8, characterized in that: The monitoring unit further includes at least one target object of the polysilicon layer and / or the active region layer, which is set as a second target object; One end of the second target object is connected to the first target object through the structure of the connection hole layer and / or the metal layer to form the monitoring unit of the comb-shaped structure; Wherein, the connection hole layer includes a contact hole layer and / or a through hole layer.

10. The monitoring structure according to any one of claims 1 to 9, characterized in that: The fuse is a polysilicon fuse, a metal fuse or a laser fuse.

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