A semiconductor device

Abstract

The present invention provides a semiconductor device comprising a substrate, on which a first conductive structure pattern and a magnetic tunnel junction array located above the first conductive structure pattern are provided, with each magnetic tunnel junction being electrically connected to the first conductive structure pattern via a first contact plug. A second conductive structure pattern is also provided on the substrate, the second conductive structure pattern being located above the magnetic tunnel junction array, with each magnetic tunnel junction being electrically connected to the second conductive structure pattern via a second contact plug. Magnetic shielding material is included in some or all of the structures of the first conductive structure pattern, the second conductive structure pattern, the first contact plug, and the second contact plug. Magnetic shielding material is provided in the vicinity of each magnetic tunnel junction for magnetic shielding, thereby enhancing the magnetic shielding effect of each magnetic tunnel junction. Furthermore, the magnetic shielding material can be added to the conductive structure pattern and the contact plug during processing, thereby simplifying the processing process.

Description

Technical Field

[0001] The present invention relates to the field of semiconductor technology, and in particular to a semiconductor device. Background Art

[0002] Magnetic Random Access Memory (MRAM), a non-volatile magnetic random access memory (RAM), has seen rapid development in recent years and boasts excellent properties. It overcomes the shortcomings of SRAM (Static Random Access Memory), which suffers from large area and high leakage after miniaturization. It also overcomes the drawbacks of DRAM (Dynamic Random Access Memory), which requires constant data refresh and consumes high power. MRAM offers several orders of magnitude greater read and write times and read / write cycles than Flash memory.

[0003] Magnetic tunnel junctions (MTJs) are used as the information storage medium in MRAM, recording information using the relative magnetization states of the free and reference layers of the MTJ. While MTJs offer several significant advantages under current process conditions, the core storage cells of current MRAM memories generally utilize MTJs with perpendicular magnetization characteristics. The principle by which the 0 and 1 states are generated is the difference in the orientation of the device's magnetic moment, making them susceptible to interference from external magnetic fields. Summary of the Invention

[0004] The present invention provides a semiconductor device for improving magnetic shielding effect and simplifying the process.

[0005] The present invention provides a semiconductor device comprising a substrate, on which is disposed a first conductive structure pattern and a magnetic tunnel junction array located above the first conductive structure pattern, wherein the magnetic tunnel junction array comprises a plurality of magnetic tunnel junctions arranged in an array, and each magnetic tunnel junction is electrically connected to the first conductive structure pattern via a first contact plug. A second conductive structure pattern is also disposed on the substrate, the second conductive structure pattern being located above the magnetic tunnel junction array, and each magnetic tunnel junction is electrically connected to the second conductive structure pattern via a second contact plug. Part or all of the first conductive structure pattern, the second conductive structure pattern, the first contact plug, and the second contact plug may contain magnetic shielding material.

[0006] In the above solution, by including magnetic shielding material in part or all of the first conductive structure pattern, the second conductive structure pattern, the first contact plug, and the second contact plug below and above the magnetic tunnel junction array, the area near each magnetic tunnel junction is magnetically shielded by the magnetic shielding material, thereby improving the magnetic shielding effect of each magnetic tunnel junction. Furthermore, the magnetic shielding material can be added to the conductive structure pattern and the contact plug during processing, thereby simplifying the processing.

[0007] In a specific embodiment, the first conductive structure pattern is a bottom metal layer array, wherein the bottom metal layer array includes a plurality of bottom metal layers corresponding one-to-one to a plurality of magnetic tunnel junctions, and each bottom metal layer is electrically connected to the corresponding magnetic tunnel junction through a first contact plug. A transistor array is also provided on the substrate, and the transistor array is located below the bottom metal layer array. The transistor array includes a plurality of transistors corresponding one-to-one to a plurality of bottom metal layers, and the drain of each transistor is electrically connected to the corresponding bottom metal layer through a third contact plug. Each bottom metal layer in the bottom metal layer array is a magnetic shielding material layer, or a composite material layer including a magnetic shielding material layer and a low resistivity material layer. By adding a magnetic shielding material to the bottom metal layer that is close to each magnetic tunnel junction, the effect of magnetic shielding of each magnetic tunnel junction is improved.

[0008] In one specific embodiment, a word line pattern is further provided in the substrate, and the word line pattern is located above the transistor array and below the bottom metal layer array. The word line pattern includes a plurality of word lines arranged in parallel and extending along a first direction, and the gate of each transistor in the transistor array is electrically connected to a word line through a fourth contact plug. Each word line in the word line pattern is a magnetic shielding material layer, or a composite material layer including a magnetic shielding material layer and a low resistivity material layer. By also adding magnetic shielding material to the word line pattern, the effect of magnetic shielding of each magnetic tunnel junction is further improved. Furthermore, the magnetic shielding material can be added to the word line during processing, thereby simplifying the process.

[0009] In one specific embodiment, the second conductive structure pattern is a bitline pattern, comprising multiple bitlines arranged in parallel and extending along a second direction, wherein the first direction is not parallel to the second direction. Each magnetic tunnel junction is electrically connected to a bitline via a second contact plug. Furthermore, each bitline in the bitline pattern comprises a magnetic shielding material layer, or a composite material layer comprising a magnetic shielding material layer and a low-resistivity material layer. By also adding magnetic shielding material to bitlines closer to the magnetic tunnel junctions, the magnetic shielding effect is enhanced.

[0010] In one specific embodiment, a redundant structure surrounding the magnetic tunnel junction is further provided on the substrate, each redundant structure comprising at least two redundant layers arranged in sequence one above the other. Any two adjacent redundant layers are spaced apart, and a redundant contact plug is connected between any two adjacent redundant layers. Each redundant layer is a magnetic shielding material layer, or a composite material layer comprising a magnetic shielding material layer and a low-resistivity material layer; the redundant contact plug is made of a magnetic shielding material. By providing redundant structures comprising magnetic shielding material around the magnetic tunnel junction, the area of ​​the magnetic shielding is made larger than the area of ​​the magnetic tunnel junction array, thereby improving the magnetic shielding effect.

[0011] In one specific embodiment, the bottommost of the at least two redundant layers is located on the same layer as the bottom metal layer pattern, and the topmost redundant layer is located on the same layer as the bit line pattern. By locating all redundant layers in the redundant structure between the bit line pattern and the bottom metal layer, the magnetic tunnel junction array is enclosed in a smaller space, thereby improving magnetic shielding.

[0012] In one specific embodiment, a source line pattern is further provided in the substrate, and the source line pattern is located above the transistor and below the word line pattern. The source line pattern includes multiple source lines arranged in parallel and extending along a third direction, and the source of each transistor is electrically connected to a source line via a fifth contact plug. Each source line in the source line pattern is a magnetic shielding material layer, or a composite material layer including a magnetic shielding material layer and a low-resistivity material layer. By also adding magnetic shielding material to the source line pattern, the effect of magnetic shielding of each magnetic tunnel junction is further improved. Furthermore, the magnetic shielding material can be added to the source line during processing, thereby simplifying the process.

[0013] In a specific embodiment, the composite material layer further includes a barrier layer sandwiched between the magnetic shielding material layer and the low resistivity material layer to prevent the magnetic shielding material layer and the low resistivity material layer from penetrating each other and thus affecting their respective performances.

[0014] In a specific embodiment, some or all of the first contact plug, the second contact plug, the third contact plug, the fourth contact plug, and the fifth contact plug are made of low-resistivity materials or materials, which can ensure the conductive performance of the contact plugs and reduce defects.

[0015] In a specific embodiment, part or all of the first contact plug, the second contact plug, the third contact plug, the fourth contact plug, and the fifth contact plug are made of magnetic shielding material, which can further improve the magnetic shielding effect.

[0016] In a specific embodiment, the magnetic shielding material is one or more materials selected from iron, cobalt, and nickel, and the low resistivity material is one or more materials selected from copper, tungsten, and aluminum, so as to improve the magnetic shielding effect and the conductive effect of the conductive structure.

[0017] In a specific embodiment, the semiconductor device is an MRAM, so as to improve the magnetic shielding effect of the MRAM. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 A cross-sectional view of a semiconductor device provided by an embodiment of the present invention;

[0019] Figure 2 A top view of a semiconductor device provided by an embodiment of the present invention;

[0020] Figure 3 A cross-sectional view of another semiconductor device provided by an embodiment of the present invention;

[0021] Figure 4 A cross-sectional view of another semiconductor device provided by an embodiment of the present invention;

[0022] Figure 5a A cross-sectional view of one step of processing a contact plug and line structure provided by an embodiment of the present invention;

[0023] Figure 5b A cross-sectional view of another step of processing a contact plug and line structure provided by an embodiment of the present invention;

[0024] Figure 5c A cross-sectional view of another step of processing a contact plug and line structure provided by an embodiment of the present invention;

[0025] Figure 5d A cross-sectional view of another step of processing a contact plug and line structure provided by an embodiment of the present invention;

[0026] Figure 5e A cross-sectional view of another step of processing a contact plug and line structure provided by an embodiment of the present invention;

[0027] Figure 6a A cross-sectional view of another step of processing a contact plug and line structure according to an embodiment of the present invention;

[0028] Figure 6b A cross-sectional view of another step of processing a contact plug and line structure according to an embodiment of the present invention;

[0029] Figure 6c A cross-sectional view of another step of processing a contact plug and line structure according to an embodiment of the present invention;

[0030] Figure 7aA cross-sectional view of one step of processing another contact plug and line structure provided by an embodiment of the present invention;

[0031] Figure 7b A cross-sectional view of another step of processing a contact plug and line structure according to an embodiment of the present invention;

[0032] Figure 7c A cross-sectional view of another step of processing a contact plug and line structure according to an embodiment of the present invention;

[0033] Figure 7d A cross-sectional view of another step of processing a contact plug and line structure according to an embodiment of the present invention;

[0034] Figure 7e A cross-sectional view of another step of processing a contact plug and line structure provided by an embodiment of the present invention.

[0035] Reference numerals:

[0036] 10-substrate 11-dielectric layer 20-magnetic tunnel junction 21-bottom electrode 22-top electrode

[0037] 31 - first conductive structure 32 - second conductive structure 33 - word line 34 - source line

[0038] 41 - first contact plug 42 - second contact plug 43 - third contact plug 44 - fourth contact plug

[0039] 45 - fifth contact plug 50 - redundant structure 51 - redundant layer 52 - redundant contact plug DETAILED DESCRIPTION

[0040] To make the objectives, technical solutions, and advantages of the embodiments of the present invention more clear, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts shall fall within the scope of protection of the present invention.

[0041] To facilitate understanding of the semiconductor device provided by the embodiment of the present invention, the following first describes an application scenario of the semiconductor device provided by the embodiment of the present invention. The semiconductor device is a memory using a magnetic tunnel junction as a memory array. The semiconductor device is described in detail below with reference to the accompanying drawings.

[0042] refer to Figure 1 and Figure 2A semiconductor device provided by an embodiment of the present invention includes a substrate 10, on which is disposed a first conductive structure 31 pattern and an array of magnetic tunnel junctions 20 located above the first conductive structure 31 pattern. The array of magnetic tunnel junctions 20 includes a plurality of magnetic tunnel junctions 20 arranged in an array, and each magnetic tunnel junction 20 is electrically connected to the first conductive structure 31 pattern via a first contact plug 41. A second conductive structure 32 pattern is also disposed on the substrate 10, located above the array of magnetic tunnel junctions 20. Each magnetic tunnel junction 20 is electrically connected to the second conductive structure 32 pattern via a second contact plug 42. Part or all of the first conductive structure 31 pattern, the second conductive structure 32 pattern, the first contact plug 41, and the second contact plug 42 may contain magnetic shielding material. Specifically, only the first conductive structure 31 pattern may contain magnetic shielding material, or only the second conductive structure 32 pattern may contain magnetic shielding material, or only the first contact plug 41 may contain magnetic shielding material, or only the second contact plug 42 may contain magnetic shielding material. Of course, magnetic shielding material may be included in any two of the first conductive structure 31 pattern, the second conductive structure 32 pattern, the first contact plug 41, and the second contact plug 42. Magnetic shielding material may be included in any three of the first conductive structure 31 pattern, the second conductive structure 32 pattern, the first contact plug 41, and the second contact plug 42. Magnetic shielding material may also be included in all of the first conductive structure 31 pattern, the second conductive structure 32 pattern, the first contact plug 41, and the second contact plug 42. The inclusion of magnetic shielding material in each structure may mean that the material of the structure is entirely composed of magnetic shielding material, or that the material of the structure contains a portion of magnetic shielding material.

[0043] In the above solution, by including magnetic shielding material in part or all of the first conductive structure 31 pattern, the second conductive structure 32 pattern, the first contact plug 41, and the second contact plug 42 below and above the magnetic tunnel junction 20 array, the area near each magnetic tunnel junction 20 is magnetically shielded by the magnetic shielding material, thereby improving the magnetic shielding effect of each magnetic tunnel junction 20. Furthermore, the magnetic shielding material can be added to the conductive structure pattern and contact plug during processing, thereby simplifying the processing process. The following describes each of the above structures in detail with reference to the accompanying drawings.

[0044] When setting the substrate 10, refer to Figure 1 The substrate 10 serves as a carrier supporting the various structures and further includes a dielectric layer 11 isolating the various conductive structures. When determining a semiconductor device, the semiconductor device may be an MRAM including an array of magnetic tunnel junctions 20 to enhance the magnetic shielding effect of the MRAM. Of course, the semiconductor device may also be other memory devices including an array of magnetic tunnel junctions 20.

[0045] When setting the pattern of the first conductive structure 31, refer to Figure 1 The first conductive structure 31 pattern can be a bottom metal layer array, wherein the bottom metal layer array includes multiple bottom metal layers corresponding one-to-one to multiple magnetic tunnel junctions 20, and each bottom metal layer is electrically connected to the corresponding magnetic tunnel junction 20 through the first contact plug 41. Specifically, when the first conductive structure 31 pattern is electrically connected to the magnetic tunnel junction 20 through the first contact plug 41, the first conductive pattern is electrically connected to the bottom electrode 21 through the first contact plug 41, and the bottom electrode 21 contacts the magnetic tunnel junction 20, thereby achieving electrical connection between the first conductive structure 31 pattern and the magnetic tunnel junction 20. A transistor array (not shown in the figure) is also provided on the substrate 10, and the transistor array is located below the bottom metal layer array. The transistor array includes multiple transistors corresponding one-to-one to the multiple bottom metal layers, and the drain of each transistor is electrically connected to the corresponding bottom metal layer through the third contact plug 43. Each bottom metal layer in the bottom metal layer array is a magnetic shielding material layer, or a composite material layer including a magnetic shielding material layer and a low resistivity material layer. By adding magnetic shielding material to the bottom metal layer that is closer to each magnetic tunnel junction 20 , the effect of magnetic shielding for each magnetic tunnel junction 20 is improved.

[0046] It should be explained that the low-resistivity material in this article refers to a material whose resistivity is less than a set value. When the set value is specifically determined, the size of the set value is related to multiple factors such as processing technology and product requirements. When specifically selecting the low-resistivity material, the low-resistivity material can be one or more materials selected from copper, tungsten, and aluminum to improve the conductive effect of the conductive structure. Correspondingly, the low-resistivity material layer refers to a layer structure composed of low-resistivity materials. When determining the magnetic shielding material, the magnetic shielding material can be one or more materials selected from iron, cobalt, and nickel to improve the magnetic shielding effect. Of course, the magnetic shielding material can also select other materials with magnetic shielding effects.

[0047] When setting each bottom metal layer in the bottom metal layer array, refer to Figure 1 , the bottom metal layer can be a composite material layer, and the composite material layer includes a magnetic shielding material layer and a low resistivity material layer. Specifically, the magnetic shielding material layer can be located above the low resistivity material layer, and the magnetic shielding material layer can be arranged at a position closer to the magnetic tunnel junction 20 to improve the magnetic shielding effect. Of course, the magnetic shielding material layer can also be arranged below the low resistivity material layer. The composite material layer can also include a barrier layer, which is sandwiched between the magnetic shielding material layer and the low resistivity material layer to prevent the two material layers from penetrating each other, thereby preventing their respective performance from being affected. The material of the barrier layer can be Ta, TaN, Ti, TiN, etc. In addition, refer to Figure 3The bottom metal layer can also be composed entirely of magnetic shielding material layers to increase the thickness of the magnetic shielding material layer and improve the magnetic shielding effect. At the same time, since the magnetic shielding material layer can also conduct electricity, it does not affect the normal electrical function. Figure 1 and Figure 4 As shown, the materials of the first contact plug 41 and the third contact plug 43 can be made of low resistivity materials to improve the conductive effect and prevent electrical defects. Figure 3 Alternatively, some or all of the first and third contact plugs 41, 43 may be made of a magnetic shielding material to enhance the magnetic shielding effect. Specifically, the first contact plug 41 may be made of a low-resistivity material, while the third contact plug 43 may be made of a magnetic shielding material. Alternatively, the first contact plug 41 may be made of a magnetic shielding material, while the third contact plug 43 may be made of a low-resistivity material. Alternatively, both the first and third contact plugs 41, 43 may be made of a magnetic shielding material. Of course, the aforementioned first conductive structure 31 pattern may also be other conductive structure patterns.

[0048] refer to Figure 4 , a word line 33 pattern can also be provided in the substrate 10, and the word line 33 pattern is located above the transistor array and below the bottom metal layer array. The word line 33 pattern includes a plurality of word lines 33 arranged in parallel and extending along the first direction, and the gate of each transistor in the transistor array is electrically connected to a word line 33 through a fourth contact plug 44. Each word line 33 in the word line 33 pattern is a magnetic shielding material layer, or a composite material layer including a magnetic shielding material layer and a low resistivity material layer. By adding magnetic shielding material to the word line 33 pattern, the effect of magnetic shielding of each magnetic tunnel junction 20 can be further improved. And when processing the word line 33, the magnetic shielding material can be added thereto, thereby simplifying the process. When specifically setting each word line 33, refer to Figure 4 , each word line 33 can be made of a composite material layer including a magnetic shielding material layer and a low-resistivity material layer. Specifically, the magnetic shielding material layer can be stacked on top of the low-resistivity material layer, so that the magnetic shielding material layer is closer to the magnetic tunnel junction 20, thereby improving the magnetic shielding effect. Of course, the magnetic shielding material layer can also be located below the low-resistivity material layer. The composite material layer can also include a barrier layer, which is sandwiched between the magnetic shielding material layer and the low-resistivity material layer to prevent the two material layers from penetrating each other, thereby preventing their respective performance from being affected. Of course, each word line 33 can also be entirely composed of a magnetic shielding material layer to increase the thickness of the magnetic shielding material layer and improve the magnetic shielding effect. At the same time, since the magnetic shielding material layer can also conduct electricity, it does not affect the normal electrical function. Reference Figure 4 The fourth contact plug 44 may be made of a low-resistivity material to improve the conductive effect and prevent electrical defects. Of course, the fourth contact plug 44 may also be made of a magnetic shielding material to improve the magnetic shielding effect.

[0049] When setting the pattern of the second conductive structure 32, refer to Figure 1 、 Figure 2 and Figure 4 The second conductive structure 32 pattern can be a bitline pattern, comprising a plurality of bitlines arranged in parallel and extending along a second direction, wherein the first direction and the second direction are not parallel. Each magnetic tunnel junction 20 is electrically connected to a bitline via a second contact plug 42. Specifically, each magnetic tunnel junction 20 contacts a top electrode 22, which is electrically connected to a bitline via a second contact plug 42, thereby achieving electrical connection between each magnetic tunnel junction 20 and the bitline pattern.

[0050] Each bit line in the bit line pattern can be made of a magnetic shielding material layer, or a composite material layer including a magnetic shielding material layer and a low resistivity material layer. By adding magnetic shielding material to the bit line that is closer to the magnetic tunnel junction 20, the magnetic shielding effect can be improved. Figure 1 , each bit line can be made of a composite material layer including a magnetic shielding material layer and a low resistivity material layer. Specifically, the magnetic shielding material layer can be stacked on top of the low resistivity material layer. Of course, the magnetic shielding material layer can also be located below the low resistivity material layer, so that the magnetic shielding material layer is closer to the magnetic tunnel junction 20, thereby improving the magnetic shielding effect. The composite material layer can also include a barrier layer, which is sandwiched between the magnetic shielding material layer and the low resistivity material layer to prevent the two material layers from penetrating each other, thereby preventing their respective performances from being affected. Of course, refer to Figure 3 Each bit line can also be composed entirely of a magnetic shielding material layer to increase the thickness of the magnetic shielding material layer and improve the magnetic shielding effect. At the same time, since the magnetic shielding material layer can also conduct electricity, it does not affect the normal electrical function. Figure 1 、 Figure 3 and Figure 4 The second contact plug 42 may be made of a low-resistivity material to improve the conductive effect and prevent electrical defects. Of course, the second contact plug 42 may also be made of a magnetic shielding material to improve the magnetic shielding effect.

[0051] refer to Figure 1 、 Figure 2 、 Figure 3 and Figure 4A redundant structure 50 surrounding the magnetic tunnel junction 20 may also be provided on the substrate 10. Each redundant structure 50 includes at least two redundant layers 51 arranged in sequence one above the other. Any two adjacent redundant layers 51 are spaced apart, and a redundant contact plug 52 is connected between any two adjacent redundant layers 51. Each redundant layer 51 is a magnetic shielding material layer, or a composite material layer including a magnetic shielding material layer and a low-resistivity material layer; the redundant contact plug 52 is made of a magnetic shielding material. By providing a redundant structure 50 containing magnetic shielding material around the magnetic tunnel junction 20, the area of ​​the magnetic shielding is made larger than the area of ​​the magnetic tunnel junction 20 array, thereby improving the magnetic shielding effect.

[0052] When specifically determining the number of redundant layers 51, the number of redundant layers 51 may be as follows: Figure 1 While two layers are shown, the number of redundant layers 51 can also be three, four, or five, etc. At least two redundant layers 51 are deposited sequentially from bottom to top, with adjacent redundant layers 51 separated by a dielectric layer 11 and connected by redundant contact plugs 52. This interconnects the at least two redundant layers 51 as a whole, enhancing magnetic shielding effectiveness. The shape of each redundant layer 51 can be rectangular, circular, or other shapes. Redundant layers 51 on the same layer are spaced apart around the array of magnetic tunnel junctions 20 to prevent the redundant layers 51 from interfering with the layout of interconnects.

[0053] When arranging at least two redundant layers 51, refer to Figure 1 , the lowest of the at least two redundant layers 51 can be located on the same layer as the bottom metal layer pattern, while the highest redundant layer 51 can be located on the same layer as the bit line pattern. By locating all redundant layers 51 in the redundant structure 50 between the bit line pattern and the bottom metal layer, the magnetic tunnel junction 20 array is enclosed in a smaller space, thereby improving magnetic shielding. Furthermore, the bottom metal layer pattern and the bit line pattern can be processed together, simplifying the process.

[0054] When specifically determining the material of the redundant structure 50, refer to Figure 1 、 Figure 2 and Figure 4 , each redundant layer 51 can be made of a magnetic shielding material, thereby enhancing the magnetic shielding effect. Furthermore, the redundant contact plugs 52 connecting two adjacent redundant layers 51 can also be made entirely of a magnetic shielding material, further enhancing the magnetic shielding effect. Furthermore, by employing a redundant structure 50 composed of redundant layers 51 and redundant contact plugs 52, the surface area of ​​each redundant layer 51 can be increased, thereby enhancing the magnetic shielding effect.

[0055] refer to Figure 4, a source line 34 pattern can also be provided in the substrate 10, and the source line 34 pattern is located above the transistor and below the word line 33 pattern. The source line 34 pattern includes a plurality of source lines 34 arranged in parallel and extending along the third direction, and the source of each transistor is electrically connected to a source line 34 through a fifth contact plug 45. And each source line 34 in the source line 34 pattern is a magnetic shielding material layer, or a composite material layer including a magnetic shielding material layer and a low resistivity material layer. By also adding magnetic shielding material to the source line 34 pattern, the effect of magnetic shielding of each magnetic tunnel junction 20 can be further improved. And when processing the source line 34, the magnetic shielding material can be added thereto, thereby simplifying the process. When specifically setting each source line 34, refer to Figure 1 , each source line 34 can be made of a composite material layer including a magnetic shielding material layer and a low resistivity material layer. Specifically, the magnetic shielding material layer can be stacked on top of the low resistivity material layer, so that the magnetic shielding material layer is closer to the magnetic tunnel junction 20, thereby improving the magnetic shielding effect. Of course, the magnetic shielding material layer can also be located below the low resistivity material layer. The composite material layer can also include a barrier layer, which is sandwiched between the magnetic shielding material layer and the low resistivity material layer to prevent the two material layers from penetrating each other, thereby preventing their respective performances from being affected. Of course, refer to Figure 3 Each source line 34 can also be composed entirely of a magnetic shielding material layer to increase the thickness of the magnetic shielding material layer and improve the magnetic shielding effect. At the same time, since the magnetic shielding material layer is also conductive, it does not affect the normal electrical function. Figure 1 、 Figure 3 and Figure 4 The material of the fifth contact plug 45 can be a low-resistivity material to improve the conductive effect, ensure the conductive performance of the contact plug, and prevent electrical defects. Of course, the material of the fifth contact plug 45 can also be a magnetic shielding material to improve the magnetic shielding effect.

[0056] In addition, it should be noted that each of the above conductive structures and contact plugs may be separated from the dielectric layer 11 in the substrate 10 by a barrier layer to prevent mutual penetration, thereby preventing the respective performances from being affected.

[0057] There are many ways to process the above-mentioned contact plug and line structures, such as Figure 5a to Figure 5e A method of processing contact plugs and line structures is shown. First, refer to Figure 5a , contact holes and line grooves are processed on the substrate 10, wherein the contact holes are used to fill and form contact plugs, and the line grooves are used to fill and form a composite material layer. Figure 5b , a barrier layer is generated in the contact holes and wire slots. Next, refer to Figure 5c, a low resistivity material layer is generated on the barrier layer, and the low resistivity material layer fills the contact hole but does not fill the line groove. Figure 5d , fill the magnetic shielding material, and fill the wire trough with magnetic shielding material. Next, refer to Figure 5e The barrier layer, low resistivity material layer and magnetic shielding material layer outside the line groove on the surface of the substrate 10 are removed to obtain the contact plug and line structure. The specific removal method can be to use CMP planarization.

[0058] When the composite material further includes a barrier layer sandwiched between the magnetic shielding material layer and the low resistivity material layer, reference Figure 6a After forming a low resistivity material layer, a barrier layer is formed on the low resistivity material layer. Figure 6b , fill the magnetic shielding material layer. After that, refer to Figure 6c , a CMP planarization is performed once to remove the two barrier layers, the low resistivity material layer and the magnetic shielding material layer to obtain the contact plug and line structure.

[0059] In addition, the contact plug and line structure can also be processed by single damascene process. Figure 7a to Figure 7e First, refer to Figure 7a , a contact hole is processed on the substrate 10. Figure 7b , a barrier layer is generated in the contact hole. Figure 7c , fill the low resistivity material layer, and use CMP planarization process to remove the low resistivity material layer outside the substrate 10 to obtain a contact plug composed of low resistivity material. Figure 7d , a dielectric layer 11 is further deposited on the substrate 10, and a line groove connected to the contact plug is processed. Figure 7e , fill the magnetic shielding material layer, and use the CMP planarization process to remove the magnetic shielding material layer outside the substrate 10 to obtain a line structure.

[0060] By including magnetic shielding material in part or all of the first conductive structure 31 pattern, the second conductive structure 32 pattern, the first contact plug 41, and the second contact plug 42 below and above the magnetic tunnel junction 20 array, the area near each magnetic tunnel junction 20 is magnetically shielded by the magnetic shielding material, thereby improving the magnetic shielding effect of each magnetic tunnel junction 20. Furthermore, the magnetic shielding material can be added to the conductive structure pattern and the contact plug during processing, thereby simplifying the processing technology.

[0061] The above description is merely a specific embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any changes or substitutions that can be easily conceived by a person skilled in the art within the technical scope disclosed in the present invention should be included in the scope of protection of the present invention. Therefore, the scope of protection of the present invention should be based on the scope of protection of the claims.

Claims

1. A semiconductor device, characterized in that: include: substrate; a first conductive structure pattern disposed on the substrate; A magnetic tunnel junction array is provided above the first conductive structure pattern, the magnetic tunnel junction array comprising a plurality of magnetic tunnel junctions arranged in an array, and each magnetic tunnel junction is electrically connected to the first conductive structure pattern via a first contact plug; the first conductive structure pattern is a bottom metal layer array, A second conductive structure pattern is provided above the magnetic tunnel junction array, and each magnetic tunnel junction is electrically connected to the second conductive structure pattern through a second contact plug; the second conductive structure pattern is a bit line pattern, Part or all of the first conductive structure pattern, the second conductive structure pattern, the first contact plug and the second contact plug contain magnetic shielding material; The substrate is further provided with a redundant structure surrounding the magnetic tunnel junction array, each redundant structure including at least two redundant layers arranged in sequence above and below; any two adjacent redundant layers are spaced apart, and a redundant contact plug is connected between any two adjacent redundant layers; Wherein, each redundant layer is a magnetic shielding material layer, or a composite material layer including a magnetic shielding material layer and a low resistivity material layer; the material of the redundant contact plug is a magnetic shielding material; The redundancy layer located at the bottom of the at least two redundancy layers is located at the same layer as the bottom metal layer array, and the redundancy layer located at the top is located at the same layer as the bit line pattern.

2. The semiconductor device according to claim 1, wherein The bottom metal layer array includes a plurality of bottom metal layers corresponding one-to-one to the plurality of magnetic tunnel junctions, and each bottom metal layer is electrically connected to the corresponding magnetic tunnel junction through the first contact plug; A transistor array is also provided on the substrate, and the transistor array is located below the bottom metal layer array; the transistor array includes a plurality of transistors corresponding one-to-one to the plurality of bottom metal layers, and the drain of each transistor is electrically connected to the corresponding bottom metal layer through a third contact plug; Each bottom metal layer in the bottom metal layer array is a magnetic shielding material layer, or a composite material layer including a magnetic shielding material layer and a low resistivity material layer.

3. The semiconductor device according to claim 2, wherein A word line pattern is further provided in the substrate, the word line pattern being located above the transistor array and below the bottom metal layer array; the word line pattern comprising a plurality of word lines arranged in parallel and extending along a first direction, the gate of each transistor in the transistor array being electrically connected to one of the word lines via a fourth contact plug; Each word line in the word line pattern is a magnetic shielding material layer, or a composite material layer including a magnetic shielding material layer and a low resistivity material layer.

4. The semiconductor device according to claim 3, wherein The bit line pattern includes a plurality of bit lines arranged in parallel and extending along a second direction, wherein the first direction is not parallel to the second direction; each magnetic tunnel junction is electrically connected to one of the bit lines through the second contact plug; Each bit line in the bit line pattern is a magnetic shielding material layer, or a composite material layer including a magnetic shielding material layer and a low resistivity material layer.

5. The semiconductor device according to claim 3, wherein A source line pattern is further provided in the substrate; the source line pattern is located above the transistor and below the word line pattern; the source line pattern includes a plurality of source lines arranged in parallel and extending along a third direction, and the source of each transistor is electrically connected to one of the source lines via a fifth contact plug; Each source line in the source line pattern is a magnetic shielding material layer, or a composite material layer including a magnetic shielding material layer and a low resistivity material layer.

6. The semiconductor device according to any one of claims 2 to 5, wherein: The composite material layer further includes a barrier layer sandwiched between the magnetic shielding material layer and the low resistivity material layer.

7. The semiconductor device according to claim 5, wherein A part or all of the first contact plug, the second contact plug, the third contact plug, the fourth contact plug, and the fifth contact plug may be made of a low-resistivity material.

8. The semiconductor device according to claim 5, wherein Part or all of the first contact plug, the second contact plug, the third contact plug, the fourth contact plug, and the fifth contact plug are made of a magnetic shielding material.

9. The semiconductor device according to claim 1, wherein The magnetic shielding material is one or more materials selected from the group consisting of iron, cobalt, and nickel, and the low resistivity material is one or more materials selected from the group consisting of copper, tungsten, and aluminum.

10. The semiconductor device according to claim 1, wherein The semiconductor device is an MRAM.

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