Groove capacitor electrode structure and groove capacitor

Abstract

The invention discloses a trench capacitor electrode structure and a trench capacitor, through an element array formed by high-density arrangement of element units with multiple rotational symmetry, and in combination with the arrangement design of an interconnection region for metal interconnection in a later process, the capacitance density is greatly improved, and meanwhile, the reliability of the trench capacitor electrode structure is improved. The surface area of the electrode is effectively increased, electric field distribution is optimized, the high-frequency characteristic of the device is improved, the electrical performance of the device is remarkably improved, and the structural stability of the device is improved.

Description

Technical Field

[0001] The present invention belongs to the technical field of capacitor structures, and in particular relates to a trench capacitor electrode structure and a trench capacitor. Background Art

[0002] In the field of silicon-based micro-nano manufacturing technology, deep trench capacitors (DTCs), as key components of three-dimensional integrated devices, continue to attract significant attention from both academia and industry. With the continued advancement of electronic device miniaturization, the demand for higher capacitance density in DTCs is also increasing.

[0003] Current technological evolution revolves around two core dimensions: the first is the vertical extension of the trench structure through high-aspect-ratio etching processes; the second is the lateral layout of high-density trench arrays using advanced photolithography technology.

[0004] However, existing deep trench capacitor designs generally only consider the high density of the trench array to increase capacitance density, attempting to increase capacitance density by increasing the surface area of ​​the electrode structure. However, the capacitance density of deep trench capacitors is actually closely related to the metal interconnects in the later process steps.

[0005] The information disclosed in this background technology section is only intended to enhance understanding of the overall background of the invention and should not be regarded as an admission or any form of suggestion that the information constitutes the prior art already known to a person skilled in the art. Summary of the Invention

[0006] The object of the present invention is to provide a trench capacitor electrode structure and a trench capacitor, which have high capacitance density and can significantly improve the electrical performance and structural stability of the device.

[0007] In order to achieve the above object, a specific embodiment of the present invention provides the following technical solutions:

[0008] A trench capacitor electrode structure, comprising:

[0009] A substrate having a first surface comprising a plurality of periodically arranged interconnected regions;

[0010] A primitive array is disposed on the first surface of the substrate, the primitive array comprising a plurality of primitive units arranged periodically, each of the primitive units corresponding to one of the interconnected regions, each of the primitive units comprising a plurality of primitive groups disposed around the corresponding interconnected region, each of the primitive groups comprising a plurality of strip-shaped primitives disposed in parallel;

[0011] Wherein, each of the primitive units has multiple rotational symmetries.

[0012] In one or more embodiments of the present invention, the multiple groups of primitive groups in each primitive unit have the same structure, and each primitive unit is formed by rotating any one group of primitive groups clockwise or counterclockwise multiple times with the interconnected area as the center point.

[0013] In one or more embodiments of the present invention, adjacent primitive units are arranged without overlapping; and / or adjacent primitive groups are arranged without overlapping.

[0014] In one or more embodiments of the present invention, the primitive unit includes three groups of primitive groups with the same structure, and the three groups of primitive groups constitute a primitive unit with three-fold rotational symmetry.

[0015] In one or more embodiments of the present invention, the three groups of primitive groups include a first primitive group, a second primitive group, and a third primitive group arranged in a ring along the interconnection area;

[0016] The first primitive group is arranged parallel to the first direction, the second primitive group is arranged parallel to the second direction, and the third primitive group is arranged parallel to the third direction, wherein the angle between the first direction, the second direction and the third direction is 120°.

[0017] In one or more embodiments of the present invention, the first direction is a horizontal direction, or an angle between the first direction and the horizontal direction is θ1, and the range of θ1 is 0°~90°.

[0018] In one or more embodiments of the present invention, the lengths L1 of the plurality of strip-shaped primitives in each group of the primitives are equal.

[0019] In one or more embodiments of the present invention, the plurality of strip-shaped primitives in each group of the primitives are arranged in a stepped manner in a direction away from the interconnection region.

[0020] In one or more embodiments of the present invention, a line connecting the centers of the plurality of strip-shaped primitives in the first primitive is parallel to the second direction, a line connecting the centers of the plurality of strip-shaped primitives in the second primitive is parallel to the third direction, and a line connecting the centers of the plurality of strip-shaped primitives in the third primitive is parallel to the first direction; or

[0021] A center line connecting the plurality of strip elements in the first element is parallel to the third direction, a center line connecting the plurality of strip elements in the second element is parallel to the first direction, and a center line connecting the plurality of strip elements in the third element is parallel to the second direction.

[0022] In one or more embodiments of the present invention, the primitive unit includes four primitive groups with the same structure, and the four primitive groups constitute a primitive unit with four-fold rotational symmetry.

[0023] In one or more embodiments of the present invention, the four primitive groups include a fourth primitive group, a fifth primitive group, a sixth primitive group, and a seventh primitive group arranged in a ring along the interconnection region;

[0024] The fourth primitive group and the sixth primitive group are arranged parallel to the first direction, and the fifth primitive group and the seventh primitive group are arranged parallel to the fourth direction, wherein the first direction is perpendicular to the fourth direction.

[0025] In one or more embodiments of the present invention, one of the first direction and the fourth direction is a horizontal direction, and the other is a vertical direction; or,

[0026] The angle between one of the first direction and the fourth direction and the horizontal direction is θ2, and the angle between the other of the first direction and the vertical direction is θ2, and the range of θ2 is 0°~90°.

[0027] In one or more embodiments of the present invention, the vertical distance D between the top of the fourth primitive group and the top of the fifth primitive group in the fourth direction is t greater than or equal to 0; and / or,

[0028] The interconnection region has a preset length L0 in the fourth direction, and a vertical distance D between the bottom of the fourth primitive group and the bottom of the fifth primitive group in the fourth direction is b Greater than or equal to L0.

[0029] In one or more embodiments of the present invention, the lengths L1 of the plurality of strip-shaped primitives in each group of the primitives are equal; and / or,

[0030] The widths W1 of the plurality of strip-shaped primitives in each group of the primitives remain unchanged or gradually decrease or gradually increase in a direction away from the interconnected region; and / or,

[0031] The distance D1 between adjacent strip-shaped primitives in each group of the primitives remains unchanged or gradually decreases or gradually increases in the direction away from the interconnected area; and / or,

[0032] The plurality of strip-shaped primitives in each group of the primitives are arranged in a stepped manner in a direction away from the interconnection area.

[0033] In one or more embodiments of the present invention, the strip-shaped element includes a column protruding from the first surface and / or a groove recessed in the first surface.

[0034] A trench capacitor is characterized by comprising the above-mentioned trench capacitor electrode structure.

[0035] Compared with the prior art, the trench capacitor electrode structure and trench capacitor of the present invention, through the high-density element array on the first surface of the substrate and the arrangement design of the interconnection area, greatly improve the trench capacitor capacitance density, effectively increase the electrode surface area and optimize the electric field distribution, thereby improving the high-frequency characteristics of the device, significantly improving the electrical performance of the device, and improving the structural stability of the device.

[0036] The trench capacitor electrode structure and trench capacitor of the present invention innovatively integrate a large number of interconnection areas in a high-density cell array, greatly facilitating subsequent metal interconnection and improving process compatibility and device reliability.

[0037] The trench capacitor electrode structure and trench capacitor of the present invention, through a high-density array arrangement of primitive units with multiple rotational symmetries combined with the arrangement of interconnected areas, can allow for more uniform material deposition and filling, reduce gaps and cracks generated during the actual process of filling materials, and improve the quality and uniformity of the device.

[0038] The trench capacitor electrode structure and trench capacitor of the present invention can evenly distribute the load, reduce the concentration of stress, and provide better deadweight distribution by setting up primitive units with multiple rotational symmetries. In addition, when the primitive units with multiple rotational symmetries are affected by external temperature changes, the thermal expansion is more uniform, which can better prevent interface damage caused by differences in material expansion coefficients, thereby improving the stability and reliability of the device.

[0039] The trench capacitor electrode structure and the trench capacitor of the present invention can balance charge distribution, reduce leakage current, optimize electric field distribution, and improve device reliability by adjusting various parameters of the cell array and the interconnection area.

[0040] The trench capacitor electrode structure and trench capacitor of the present invention can shorten the current path, reduce resistance, and lower ESR (equivalent series resistance); by setting up a basic unit unit with multiple rotational symmetries, it can offset part of the parasitic inductance, improve high-frequency response characteristics, and reduce ESL (equivalent series inductance). BRIEF DESCRIPTION OF THE DRAWINGS

[0041] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are only some embodiments recorded in the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0042] Figure 1 Schematic diagram of the planar morphology of the trench capacitor electrode structure in Example 1 of the present invention;

[0043] Figure 2 for Figure 1 Detailed diagram of the primitive unit in ;

[0044] Figure 3 Schematic diagram of the planar morphology of the trench capacitor electrode structure in Example 2 of the present invention;

[0045] Figure 4 for Figure 3 Detailed diagram of the primitive unit in ;

[0046] Figure 5 Detailed diagram of a basic unit of a trench capacitor electrode structure in Example 3 of the present invention;

[0047] Figure 6 Detailed diagram of a basic unit of a trench capacitor electrode structure in Example 4 of the present invention;

[0048] Figure 7 Schematic diagram of the planar morphology of the trench capacitor electrode structure in Example 5 of the present invention;

[0049] Figure 8 for Figure 7 Detailed diagram of the primitive unit in ;

[0050] Figure 9 Detailed diagram of a basic unit of a trench capacitor electrode structure in Example 6 of the present invention;

[0051] Figure 10 Schematic diagram of the planar morphology of the trench capacitor electrode structure in Example 7 of the present invention;

[0052] Figure 11 for Figure 10 Detailed diagram of the primitive unit in ;

[0053] Figure 12 Detailed diagram of a basic unit of a trench capacitor electrode structure in Example 8 of the present invention;

[0054] Figure 13 Detailed diagram of a basic unit of a trench capacitor electrode structure in Example 9 of the present invention;

[0055] Figure 14 Schematic diagram of the planar morphology of the trench capacitor electrode structure of Comparative Example 1 (no interconnection region is provided);

[0056] Figure 15 A comparison diagram of capacitance density of trench capacitor structures fabricated using the trench capacitor electrode structures of Example 1, Example 5, and Comparative Example 1 of the present invention;

[0057] Figure 16 Schematic diagram of the planar morphology of the trench capacitor electrode structure of Comparative Example 2 (no interconnection region is provided);

[0058] Figure 17 The trench capacitor electrode structure of embodiment 2, embodiment 5, and embodiment 7 of the present invention and Figure 16 The three-dimensional simulated warping cloud diagram of the trench capacitor electrode structure of Comparative Example 2 is shown;

[0059] Figure 18 For Figure 17 The change diagram of the unit capacity density warping value corresponding to the warping cloud diagram. DETAILED DESCRIPTION

[0060] In order to enable those skilled in the art to better understand the technical solutions of the present invention, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the accompanying drawings of 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 should fall within the scope of protection of the present invention.

[0061] As mentioned in the background, the current technological evolution of trench capacitors, which face increasing demands for capacitance density, revolves around two core dimensions: vertical extension of the trench structure through high-aspect-ratio etching processes, and the lateral layout of high-density trench arrays using advanced photolithography. While the technology for vertical extension of the trench structure through high-aspect-ratio etching processes is currently mature, the lateral layout of high-density trench arrays using advanced photolithography still has potential for further development.

[0062] The design of high-density trench arrays often requires finding an optimal balance between parasitic parameter suppression and mechanical reliability to at least ensure the mechanical stability of the structure and the subsequent filling of the dielectric layer and poly layer. However, in order to improve the capacitance density, the existing deep trench capacitor design generally only considers the high density of the trench array, attempting to increase the capacitance density by increasing the surface area of ​​the electrode structure. However, the capacitance density of deep trench capacitors is actually closely related to the metal interconnection in the later process.

[0063] Based on this, the present invention provides a trench capacitor electrode structure and a trench capacitor, which greatly improves the capacitance density while effectively increasing the electrode surface area and optimizing the electric field distribution, thereby improving the high-frequency characteristics of the device, significantly improving the electrical performance of the device, and improving the structural stability of the device.

[0064] The trench capacitor electrode structure and trench capacitor of the present invention perfectly solve the technical bottlenecks of traditional deep trench capacitors in terms of high capacitance density, structural stability and process compatibility, and can be widely used in aerospace electronics, MEMS sensors, advanced packaging and high-power energy storage devices.

[0065] The trench capacitor electrode structure of the present invention comprises a substrate and a primitive array disposed on the substrate. The substrate has a first surface comprising a plurality of periodically arranged interconnected regions. The primitive array is disposed on the first surface of the substrate and comprises a plurality of periodically arranged primitive units, each primitive unit corresponding to an interconnected region. Each primitive unit comprises a plurality of primitive groups disposed around its corresponding interconnected region, each primitive group comprising a plurality of parallel strip-shaped primitives. Each primitive unit has multiple rotational symmetries.

[0066] Specifically, the multiple groups of primitive groups within each primitive unit have the same structure. Each primitive unit is formed by rotating any one of the primitive groups multiple times clockwise or counterclockwise around the interconnected region. Adjacent primitive units and adjacent primitive groups do not overlap.

[0067] In one embodiment, the primitive unit includes three primitive groups with the same structure, and the three primitive groups constitute a primitive unit with three-fold rotational symmetry.

[0068] In this embodiment, the three primitive groups include a first primitive group, a second primitive group, and a third primitive group arranged in a ring along the interconnected region; the first primitive group is arranged parallel to a first direction, the second primitive group is arranged parallel to a second direction, and the third primitive group is arranged parallel to a third direction, wherein the angle between the first direction, the second direction, and the third direction is 120°. The first direction is horizontal, or the angle between the first direction and the horizontal direction is θ1, and θ1 ranges from 0° to 90°.

[0069] In one embodiment, the primitive unit includes four primitive groups with the same structure, and the four primitive groups constitute a primitive unit with four-fold rotational symmetry.

[0070] In this embodiment, the four primitive groups include a fourth primitive group, a fifth primitive group, a sixth primitive group, and a seventh primitive group arranged in a ring along the interconnected region; the fourth primitive group and the sixth primitive group are arranged parallel to a first direction, and the fifth primitive group and the seventh primitive group are arranged parallel to a fourth direction, wherein the first direction is perpendicular to the fourth direction. One of the first direction and the fourth direction is horizontal, and the other is vertical, or one of the first direction and the fourth direction forms an angle θ2 with the horizontal direction, and the other forms an angle θ2 with the vertical direction, wherein θ2 ranges from 0° to 90°.

[0071] The present invention also provides a trench capacitor, comprising the above-mentioned trench capacitor electrode structure.

[0072] The trench capacitor electrode structure and trench capacitor of the present invention, through the high-density element array on the first surface of the substrate and the arrangement design of the interconnection area, greatly improve the trench capacitor capacitance density, effectively increase the electrode surface area and optimize the electric field distribution, thereby improving the high-frequency characteristics of the device, significantly improving the electrical performance of the device, and improving the structural stability of the device.

[0073] The trench capacitor electrode structure of the present invention is further described below with reference to a number of specific embodiments.

[0074] Example 1:

[0075] like Figure 1 and Figure 2 As shown, the trench capacitor electrode structure in this embodiment includes a substrate 10 and a cell array formed on the substrate 10 .

[0076] The substrate 10 has a first surface that serves as a supporting structure for the cell array. The first surface includes a plurality of first regions A arranged in a periodic array. Each first region A includes a central interconnected region A1 and peripheral cell regions A2 surrounding interconnected region A1. In this embodiment, the first regions A are hexagonal, and the interconnected regions A1 are triangular. It will be understood that the first regions A on the first surface are virtual regions, defined for the purpose of facilitating the description of the cell units 20 in the cell array below.

[0077] In this embodiment, a three-dimensional rectangular coordinate system is established on the first surface of the substrate 10, with the first surface serving as the bottom plane. The horizontal direction is defined as the first direction, represented in the diagram as the x-direction. Two directions on the bottom plane that are 120° clockwise and counterclockwise from the horizontal direction are defined as the second and third directions, respectively. The second direction is represented in the diagram as the m-direction, and the third direction is represented in the diagram as the n-direction. The direction perpendicular to the first surface is defined as the z-direction.

[0078] A primitive array is disposed on the first surface of a substrate 10. The primitive array includes a plurality of periodically distributed primitive units 20, with adjacent primitive units 20 being arranged without overlap. Each primitive unit 20 corresponds to a first region A. Each primitive unit 20 includes three primitive groups 21 disposed within a peripheral primitive region A2 of the corresponding first region A. The three primitive groups 21 are disposed around an interconnected region A1 of the first region A in which they are located.

[0079] The three groups of primitive groups 21 have the same structure. Any of the three groups 21 is rotated three times, either clockwise or counterclockwise, by 120°, around the corresponding interconnected region A1 to form a primitive unit 20. Thus, each primitive unit 20 has three-fold rotational symmetry. Adjacent primitive groups 21 are not arranged to overlap.

[0080] Each element group 21 includes three strip-shaped elements 211 arranged in parallel and parallel to each other. Each strip-shaped element 211 has a length L1 and a width W1. The strip-shaped elements 211 can be pillars protruding from the first surface of the substrate 10 (in the z-direction shown in the figure) perpendicular to the first surface, or they can be grooves recessed into the first surface of the substrate 10 (in the z-direction shown in the figure) perpendicular to the first surface. The strip-shaped elements 211 are part of the electrode structure.

[0081] In this embodiment, the three strip elements 211 are of equal length, L1; the three strip elements 211 are of equal width, W1; and adjacent strip elements 211 are equally spaced, D1. The center lines connecting the three strip elements 211 in each element group are perpendicular to the extension direction of the strip elements 211 in that element group.

[0082] refer to Figure 2 As shown, the three groups of primitives 21 of the primitive unit 20 are arranged in a ring along the interconnection area A1. The three groups 21 are, in a clockwise direction, the first primitive group 21a, the second primitive group 21b, and the third primitive group 21c. The first primitive group 21a extends parallel to the first direction (the x-direction in the diagram), the second primitive group 21b extends parallel to the second direction (the m-direction in the diagram), and the third primitive group 21c extends parallel to the third direction (the n-direction in the diagram). The centerline of the three strip-shaped primitives 211 in the first primitive group 21a is perpendicular to the first direction (the x-direction in the diagram); the centerline of the three strip-shaped primitives 211 in the second primitive group 21b is perpendicular to the second direction (the m-direction in the diagram); and the centerline of the three strip-shaped primitives 211 in the third primitive group 21c is perpendicular to the third direction (the n-direction in the diagram).

[0083] The following description will be made by taking the positional relationship between the first primitive group 21a and the second primitive group 21b as an example. The bottom of the first primitive group 21a and the top of the second primitive group 21b have a distance D perpendicular to the first direction. t2 , D t2 Greater than 0.

[0084] It can be understood that since the primitive unit 20 is a figure with three-fold rotational symmetry, after the primitive unit 20 is rotated 120° counterclockwise, the positional relationship between the second primitive group 21b and the third primitive group 21c should be consistent with the positional relationship between the first primitive group 21a and the second primitive group 21b; and by analogy, the positional relationship between the third primitive group 21c and the first primitive group 21a should still be consistent with the positional relationship between the first primitive group 21a and the second primitive group 21b.

[0085] refer to Figure 1 As shown, in this embodiment, the distance between adjacent primitive units 20 in the first direction (x direction) is P 11 The distance between adjacent primitive units 20 in the direction perpendicular to the first direction is P 12 , P 21 and P 22 The values ​​of are all greater than 0. In the first direction (x direction), the adjacent primitive units 20 have a staggered distance P perpendicular to the first direction. 13 , P 13 The value is greater than 0 and preferably P 12 half.

[0086] Understandably, P 11 It is defined as the straight line distance between the centers of adjacent primitive units 20 in the first direction; 12 It is defined as the straight line distance between the centers of adjacent primitive units 20 perpendicular to the first direction; P 13 It is defined as the straight line distance between the centers of adjacent primitive units 20 in the first direction and perpendicular to the first direction.

[0087] It is understandable that the above parameters length L1, width W1, spacing D1, spacing D t2 , distance P 11 , distance P 12 , offset distance P 13 These are not fixed and can be adjusted adaptively based on the actual process node or structural requirements. If the length L1 is reduced, the width W1 is increased, or the spacing D1 is reduced, while the other variable variables remain unchanged, the total capacitance of the resulting cell array will be increased after capacitors are fabricated later.

[0088] Example 2:

[0089] refer to Figure 3 and Figure 4 As shown, the trench capacitor electrode structure in this embodiment includes a substrate 10 and a cell array formed on the substrate 10 .

[0090] The substrate 10 has a first surface that serves as a supporting structure for the cell array. The first surface includes a plurality of first regions A arranged in a periodic array. Each first region A includes a central interconnected region A1 and peripheral cell regions A2 surrounding interconnected region A1. In this embodiment, the first regions A are hexagonal, and the interconnected regions A1 are triangular. It will be understood that the first regions A on the first surface are virtual regions, defined for the purpose of facilitating the description of the cell units 20 in the cell array below.

[0091] In this embodiment, a three-dimensional rectangular coordinate system is established on the first surface of the substrate 10, with the first surface serving as the bottom plane. The horizontal direction is defined as the first direction, represented in the diagram as the x-direction. Two directions on the bottom plane that are 120° clockwise and counterclockwise from the horizontal direction are defined as the second and third directions, respectively. The second direction is represented in the diagram as the m-direction, and the third direction is represented in the diagram as the n-direction. The direction perpendicular to the first surface is defined as the z-direction.

[0092] A primitive array is disposed on the first surface of a substrate 10. The primitive array includes a plurality of periodically distributed primitive units 20, with adjacent primitive units 20 being arranged without overlap. Each primitive unit 20 corresponds to a first region A. Each primitive unit 20 includes three primitive groups 21 disposed within a peripheral primitive region A2 of the corresponding first region A. The three primitive groups 21 are disposed around an interconnected region A1 of the first region A in which they are located.

[0093] The three groups of primitive groups 21 have the same structure. Any of the three groups 21 is rotated three times, either clockwise or counterclockwise, by 120°, around the corresponding interconnected region A1 to form a primitive unit 20. Thus, each primitive unit 20 has three-fold rotational symmetry. Adjacent primitive groups 21 are not arranged to overlap.

[0094] Each element group 21 includes three strip-shaped elements 211 arranged in parallel and parallel to each other. Each strip-shaped element 211 has a length L1 and a width W1. The strip-shaped elements 211 can be pillars protruding from the first surface of the substrate 10 (in the z-direction shown in the figure) perpendicular to the first surface, or they can be grooves recessed into the first surface of the substrate 10 (in the z-direction shown in the figure) perpendicular to the first surface. The strip-shaped elements 211 are part of the electrode structure.

[0095] In this embodiment, the three strip elements 211 are of equal length, L1; the three strip elements 211 are of equal width, W1; and adjacent strip elements 211 are equally spaced, D1. The three strip elements 211 in each element group are arranged in a stepped pattern away from the interconnected area A1, and the centerline connecting the three strip elements 211 in each element group is parallel to the extension direction of the strip elements 211 in the next clockwise element group.

[0096] refer to Figure 4 As shown, the three groups of primitive groups 21 of the primitive unit 20 are arranged in a ring along the interconnection area A1. The three groups 21 are, in a clockwise direction, a first primitive group 21a, a second primitive group 21b, and a third primitive group 21c. The first primitive group 21a extends parallel to a first direction (the x-direction in the figure), the second primitive group 21b extends parallel to a second direction (the m-direction in the figure), and the third primitive group 21c extends parallel to a third direction (the n-direction in the figure). The center line of the three strip elements 211 in the first element group 21a is arranged parallel to the second direction (m direction in the figure), that is, the center line of the three strip elements 211 in the first element group 21a is parallel to the extension direction of the three strip elements 211 in the second element group 21b; the center line of the three strip elements 211 in the second element group 21b is arranged parallel to the third direction (n direction in the figure), that is, the center line of the three strip elements 211 in the second element group 21b is parallel to the extension direction of the three strip elements 211 in the third element group 21c; the center line of the three strip elements 211 in the third element group 21c is arranged parallel to the first direction (x direction in the figure), that is, the center line of the three strip elements 211 in the third element group 21c is parallel to the extension direction of the three strip elements 211 in the first element group 21a.

[0097] The following description will be made by taking the positional relationship between the first primitive group 21a and the second primitive group 21b as an example. The top of the first primitive group 21a and the top of the second primitive group 21b have a distance D perpendicular to the first direction. t1 , D t1 The bottom of the first primitive group 21a and the bottom of the strip primitive 211 closest to the interconnection area A1 in the second primitive group 21b have a distance D perpendicular to the first direction. t2 , D t2 Greater than 0 and D t2 is greater than or equal to a preset length L0 of the interconnection area A1 in the direction perpendicular to the first direction.

[0098] It can be understood that since the primitive unit 20 is a figure with three-fold rotational symmetry, after the primitive unit 20 is rotated 120° counterclockwise, the positional relationship between the second primitive group 21b and the third primitive group 21c should be consistent with the positional relationship between the first primitive group 21a and the second primitive group 21b; and by analogy, the positional relationship between the third primitive group 21c and the first primitive group 21a should still be consistent with the positional relationship between the first primitive group 21a and the second primitive group 21b.

[0099] refer to Figure 3 As shown, in this embodiment, the distance between adjacent primitive units 20 in the first direction (x direction) is P 11 The distance between adjacent primitive units 20 in the direction perpendicular to the first direction is P 12 Equidistant arrangement, P 11 and P 12 The values ​​of are all greater than 0. In the first direction (x direction), the adjacent primitive units 20 have a staggered distance P perpendicular to the first direction. 13 , P 13 The value of is greater than 0.

[0100] Understandably, P 11 It is defined as the straight line distance between the centers of adjacent primitive units 20 in the first direction; 12 It is defined as the straight line distance between the centers of adjacent primitive units 20 perpendicular to the first direction; P 13 It is defined as the straight line distance between the centers of adjacent primitive units 20 in the first direction and perpendicular to the first direction.

[0101] It is understandable that the above parameters length L1, width W1, spacing D1, spacing D t1 , spacing D t2 , distance P 11 , distance P 12 , offset distance P 13 The preset length L0 of interconnect area A1 is not fixed and can be adjusted based on the actual process node or structural requirements. If the length L1 is reduced, the width W1 is increased, or the spacing D1 is reduced, while the other variable variables remain unchanged, the total capacitance of the resulting cell array will be increased after capacitors are fabricated.

[0102] Example 3:

[0103] refer to Figure 5As shown, the arrangement of the basic unit cells of the trench capacitor electrode structure of this embodiment is exactly the same as that of embodiment 2. The difference is that the basic unit cell 20 in this embodiment is a chiral unit of the basic unit cell 20 in embodiment 2, that is, the basic unit cell 20 in this embodiment is mirror-symmetrical to the basic unit cell 20 in embodiment 2, but cannot completely overlap.

[0104] Example 4:

[0105] refer to Figure 6 As shown, the arrangement of the primitive units of the trench capacitor electrode structure in this embodiment is exactly the same as that in Example 2. The difference is that the primitive unit 20 in this embodiment is formed by rotating the primitive unit group 21 in the primitive unit 20 in Example 2 counterclockwise or clockwise by θ1 with the vertex angle of the strip primitive 211 away from the edge of the interconnection area A1 as the center point. That is, in this embodiment, the angle between the first direction and the horizontal direction is defined as θ1, and the range of θ1 is between 0° and 90°. The angle between any two directions in the first direction, the second direction, and the third direction is still 120°.

[0106] It can be understood that in the above-mentioned embodiments 1 to 4, each group of element groups 21 contains three strip elements 211, and the three strip elements 211 are all set with equal length and width, and the adjacent strip elements 211 are set at equal intervals. In other embodiments, each group of element groups 21 can also include four or more strip elements 211, and / or the width W1 of the multiple strip elements 211 can also gradually decrease or gradually increase in the direction away from their corresponding interconnection area A1; and / or the spacing D1 between adjacent strip elements 211 in each group of element groups 21 can also gradually decrease or gradually increase in the direction away from their corresponding interconnection area A1. In this technical solution, the gradual setting of the width W1 and / or the spacing D1 can regulate the stress of the electrode layer and the dielectric layer formed on the electrode structure later to prevent warping. It is understandable that the widths W1 of the plurality of strip elements 211 may also be different in the direction away from their corresponding interconnected regions A1; the spacing D1 between adjacent strip elements 211 in each element group 21 may also be different in the direction away from their corresponding interconnected regions A1.

[0107] Example 5:

[0108] refer to Figure 7 and Figure 8 As shown, the trench capacitor electrode structure in this embodiment includes a substrate 10 and a cell array formed on the substrate 10 .

[0109] The substrate 10 has a first surface that serves as a supporting structure for the cell array. The first surface includes a plurality of first regions A arranged in a periodic array. Each first region A includes a central interconnected region A1 and peripheral cell regions A2 surrounding interconnected region A1. In this embodiment, the first regions A and interconnected regions A1 are square. It will be appreciated that the first regions A on the first surface are virtual regions, defined for ease of reference to the description of the cell units 20 in the cell array below.

[0110] In this embodiment, a three-dimensional rectangular coordinate system is established on the first surface of the substrate 10 as the bottom plane. The horizontal direction is defined as the first direction, represented by the x-direction in the figure, the vertical direction is defined as the fourth direction, represented by the y-direction in the figure, and the direction perpendicular to the first surface is defined as the z-direction.

[0111] A primitive array is disposed on the first surface of a substrate 10. The primitive array includes a plurality of periodically distributed primitive units 20, with adjacent primitive units 20 being arranged without overlap. Each primitive unit 20 corresponds to a first region A. Each primitive unit 20 includes four primitive groups 21 disposed within a peripheral primitive region A2 of the corresponding first region A. The four primitive groups 21 are disposed around an interconnected region A1 of the first region A in which they are located.

[0112] The four groups of primitive sets 21 have the same structure. Any of the four groups 21 is rotated four times, either clockwise or counterclockwise, by 90°, around the corresponding interconnected region A1 to form a primitive unit 20. Thus, each primitive unit 20 has four-fold rotational symmetry. Adjacent primitive sets 21 are not arranged to overlap.

[0113] Each element group 21 includes three strip-shaped elements 211 arranged side by side in a direction away from the interconnection area A1. Each strip-shaped element 211 has a length L1 and a width W1. The strip-shaped elements 211 can be pillars protruding from the first surface of the substrate 10 (in the z-direction shown in the figure) perpendicular to the first surface, or grooves recessed into the first surface of the substrate 10 (in the z-direction shown in the figure) perpendicular to the first surface. The strip-shaped elements 211 are part of the electrode structure.

[0114] In this embodiment, the three strip elements 211 are of equal length, L1; the three strip elements 211 are of equal width, W1; and adjacent strip elements 211 are spaced equally apart, D1. The center line connecting the three strip elements 211 in each element group 21 is perpendicular to the extension direction of the strip elements 211 in that element group.

[0115] refer to Figure 8As shown, the four groups 21 of the primitive unit 20 are arranged in a ring along the interconnection area A1. The four groups 21, in a clockwise direction, are the fourth group 21d, the fifth group 21e, the sixth group 21f, and the seventh group 21g. The fourth and sixth groups 21d and 21f are arranged parallel to the first direction (the x-direction in the figure), while the fifth and seventh groups 21e and 21g are arranged parallel to the fourth direction. In this embodiment, the fourth direction is perpendicular to the first direction, i.e., the y-direction in the figure.

[0116] The following description will be made by taking the positional relationship between the fourth primitive group 21d and the fifth primitive group 21e as an example. The vertical distance D between the top of the fourth primitive group 21d and the top of the fifth primitive group 21e in the fourth direction (the y direction in the figure) is t1 = 0. The vertical distance D between the bottom of the fourth primitive group 21d and the bottom of the fifth primitive group 21e in the fourth direction (the y direction in the figure) is t2 The vertical distance between the right end of the fourth primitive group 21d and the left end of the fifth primitive group 21e in the first direction (x direction) is D2, which is greater than 0.

[0117] It can be understood that since the primitive unit 20 is a figure with four-fold rotational symmetry, after the primitive unit 20 is rotated 90° counterclockwise, the positional relationship between the fifth primitive group 21e and the sixth primitive group 21f should be consistent with the positional relationship between the fourth primitive group 21d and the fifth primitive group 21e; ​​and by analogy, the positional relationship between the sixth primitive group 21f and the seventh primitive group 21g should still be consistent with the positional relationship between the fourth primitive group 21d and the fifth primitive group 21e; ​​and the positional relationship between the seventh primitive group 21g and the fourth primitive group 21d should still be consistent with the positional relationship between the fourth primitive group 21d and the fifth primitive group 21e.

[0118] refer to Figure 7 As shown, in this embodiment, the primitive unit 20 is spaced apart in the first direction (x direction) by a distance P 21 Arranged equidistantly, with a distance P in the fourth direction (y direction) 22 Equidistant arrangement, P 21 Equal to P 22 And both are greater than 0. In the first direction (x direction), adjacent primitive units 20 are arranged without misalignment in the fourth direction (y direction).

[0119] In other embodiments, in the first direction (x direction), adjacent primitive units 20 may also have a staggered distance P in the fourth direction (y direction). 23 (not shown), the offset distance P 23 The value of is greater than 0.

[0120] Understandably, P 21 It is defined as the straight line distance between the centers of adjacent primitive units 20 in the first direction; 22 is defined as the straight-line distance between the centers of adjacent primitive units 20 in the fourth direction; 23 It is defined as the straight-line distance in the fourth direction between the centers of adjacent cellular units 20 in the first direction.

[0121] It is understandable that the above parameters length L1, width W1, spacing D1, spacing D t1 , spacing D t2 , distance P 21 , distance P 22 , offset distance P 23 The preset length L0 of interconnect area A1 is not fixed and can be adjusted based on the actual process node or structural requirements. If the length L1 is reduced, the width W1 is increased, or the spacing D1 is reduced, while the other variable variables remain unchanged, the total capacitance of the resulting cell array will be increased after capacitors are fabricated.

[0122] Example 6:

[0123] refer to Figure 9 As shown, the arrangement of the basic unit cells of the trench capacitor electrode structure of this embodiment is exactly the same as that of embodiment 5. The difference is that the basic unit cell 20 in this embodiment is a chiral unit of the basic unit cell 20 in embodiment 5, that is, the basic unit cell 20 in this embodiment is mirror-symmetrical to the basic unit cell 20 in embodiment 5, but cannot completely overlap.

[0124] Example 7:

[0125] refer to Figure 10 and Figure 11 As shown, the arrangement of the basic unit cells of the trench capacitor electrode structure in this embodiment is exactly the same as that in embodiment 5.

[0126] In this embodiment, each element group 21 still includes three strip-shaped elements 211 arranged side by side in a direction away from the interconnection area A1. Each strip-shaped element 211 has a length L1 and a width W1. The strip-shaped elements 211 can be pillars protruding from the first surface of the substrate 10 along a direction perpendicular to the first surface (z-direction in the figure), or they can be grooves recessed into the first surface along a direction perpendicular to the first surface of the substrate 10 (z-direction in the figure). The strip-shaped elements 211 are part of the electrode structure.

[0127] In this embodiment, the three strip elements 211 are of equal length, L1; the three strip elements 211 are of equal width, W1; and adjacent strip elements 211 are spaced equally apart, D1. The center lines connecting the three strip elements 211 in each element group 21 are perpendicular to the direction in which the strip elements 211 in that element group extend.

[0128] The four groups 21 of the primitive unit 20 are arranged in a ring along the interconnection area A1. The four groups 21, arranged clockwise, are the fourth group 21d, the fifth group 21e, the sixth group 21f, and the seventh group 21g. The fourth and sixth groups 21d and 21f are arranged parallel to the first direction (the x-direction in the figure), while the fifth and seventh groups 21e and 21g are arranged parallel to the fourth direction. In this embodiment, the fourth direction is perpendicular to the first direction, i.e., the y-direction in the figure.

[0129] The difference between this embodiment and the fifth embodiment is that the arrangement of the primitive groups constituting the primitive unit 20 in this embodiment is different from that in the fifth embodiment.

[0130] The following description will be made by taking the positional relationship between the fourth primitive group 21 d and the fifth primitive group 21 e as an example.

[0131] refer to Figure 11 As shown, the difference between this embodiment and embodiment 5 is that the vertical distance D between the top of the fourth primitive group 21d and the top of the fifth primitive group 21e in the fourth direction (the y direction in the figure) is t1 The vertical distance D between the bottom of the fourth primitive group 21d and the bottom of the fifth primitive group 21e in the fourth direction (the y direction in the figure) is greater than 0 but less than the length L1 of the strip element. t2 The length L0 of the interconnection region A1 in the fourth direction (the y direction in the figure) is greater than or equal to the predetermined length L0 of the interconnection region A1 in the fourth direction (the y direction in the figure) but still less than the length L1 of the strip element. The predetermined length L0 of the interconnection region A1 in the fourth direction (the y direction in the figure) in this embodiment is less than the predetermined length L0 of the interconnection region A1 in the fourth direction (the y direction in the figure) in Example 5.

[0132] Example 8:

[0133] refer to Figure 12 As shown, the arrangement of the primitive units of the trench capacitor electrode structure in this embodiment is identical to that in Example 7. The difference is that the primitive units 20 in this embodiment are formed by rotating each primitive group 21 of the primitive units 20 in Example 7 counterclockwise or clockwise by θ2, with the vertex angle of the strip primitive 211 furthest from the edge of the interconnection area A1 as the center point. That is, in this embodiment, the angle between the defined first direction and the horizontal direction is θ2, and θ2 ranges from 0° to 90°.

[0134] Example 9:

[0135] refer to Figure 13 As shown, the arrangement of the basic unit cells of the trench capacitor electrode structure in this embodiment is exactly the same as that in embodiment 5.

[0136] In this embodiment, each element group 21 still includes three strip-shaped elements 211 arranged side by side in a direction away from the interconnection area A1. Each strip-shaped element 211 has a length L1 and a width W1. The strip-shaped elements 211 can be pillars protruding from the first surface of the substrate 10 along a direction perpendicular to the first surface (z-direction in the figure), or they can be grooves recessed into the first surface along a direction perpendicular to the first surface of the substrate 10 (z-direction in the figure). The strip-shaped elements 211 are part of the electrode structure.

[0137] In this embodiment, the three strip elements 211 are of equal length, and the length is L1; the three strip elements 211 are of equal width, and the width is W1; the adjacent strip elements 211 in the three strip elements 211 are of equal spacing, and the spacing is D1.

[0138] The difference between the trench capacitor electrode structure in this embodiment and that in the fifth embodiment is that the arrangement of the strip-shaped primitives 211 in the primitive group in the primitive unit 20 in this embodiment is different from that in the fifth embodiment.

[0139] Specifically, in this embodiment, the three strip elements 211 in each element group are distributed in a stepped manner in a direction away from the interconnection area A1 , and the distance between the ends of two adjacent strip elements 211 in each element group is equal or gradually decreases.

[0140] It can be understood that in the above-mentioned embodiments 5 to 9, each group of element groups 21 contains three strip elements 211, and the three strip elements 211 are all set with equal length and width, and the adjacent strip elements 211 are set at equal intervals. In other embodiments, each group of element groups 21 can also include four or more strip elements 211, and / or the width W1 of the multiple strip elements 211 can also gradually decrease or gradually increase in the direction away from their corresponding interconnection area A1; and / or the spacing D1 between adjacent strip elements 211 in each group of element groups 21 can also gradually decrease or gradually increase in the direction away from their corresponding interconnection area A1. In this technical solution, the gradual setting of the width W1 and / or the spacing D1 can regulate the stress of the electrode layer and the dielectric layer formed on the electrode structure later, thereby preventing warping. It is understandable that the widths W1 of the plurality of strip elements 211 may also be different in the direction away from their corresponding interconnected regions A1; the spacing D1 between adjacent strip elements 211 in each element group 21 may also be different in the direction away from their corresponding interconnected regions A1.

[0141] It should be noted that the above embodiments 1-4 can be combined with each other as long as they are not contradictory. The above embodiments 5-9 can also be combined with each other as long as they are not contradictory. In other embodiments, the chiral units of the unit cell 20 in the above embodiments 1-9 can also be used as unit cells and arranged periodically to form a new trench capacitor electrode structure.

[0142] It is understood that the trench capacitor structure can be obtained by fabricating subsequent layers (using conventional methods) on the first surface of the substrate and the outer surfaces of the strip-shaped elements of the trench capacitor electrode structure. Since the fabrication of the subsequent layers is not the focus of this application, it will not be elaborated in detail here.

[0143] refer to Figure 15 As shown, Figure 15 For the embodiment 1, embodiment 5 and comparative example 1 of the present invention ( Figure 14 The capacitance density comparison diagram of the trench capacitor structure made of the trench capacitor electrode structure shown in FIG. When the depth or height of the stripe element 211 is 10 μm, the capacitance density of the comparative example 1 is 34.3 nF / mm 2 The capacitance density of Example 1 is 55.9nf / mm 2 The capacitance density of Example 5 is 84.7nf / mm 2 When the depth or height of the stripe element 211 is 15 μm, the capacitance density of Comparative Example 1 is 64 nf / mm 2 The capacitance density of Example 1 is 80.5nf / mm 2 The capacitance density of Example 5 is 123.7nf / mm 2 When the depth or height of the stripe element 211 is 20 μm, the capacitance density of Comparative Example 1 is 84.6 nf / mm 2 The capacitance density of Example 1 is 105.1nf / mm 2 The capacitance density of Example 5 is 162.7nf / mm 2 When the depth or height of the stripe element 211 is 25 μm, the capacitance density of Comparative Example 1 is 105.2 nf / mm 2 The capacitance density of Example 1 is 129.7nf / mm 2 The capacitance density of Example 5 is 201.7nf / mm 2 When the depth or height of the stripe element 211 is 30 μm, the capacitance density of Comparative Example 1 is 125.8 nf / mm 2 The capacitance density of Example 1 is 154.3nf / mm 2 The capacitance density of Example 5 is 240.7nf / mm 2 .from Figure 15It can be seen that the capacitance density of the trench capacitor structure manufactured by the trench capacitor electrode structure of the present embodiment 1 and embodiment 5 is significantly increased compared with the trench capacitor structure manufactured by the trench capacitor electrode structure without the interconnection region.

[0144] In the mechanical simulation, a 2 mm × 2 mm × 0.1 mm three-dimensional structure model was established to simulate the trench capacitor structure on the substrate. The trench depth was set to 40 μm, and the thickness of the polysilicon (PS) layer filled in the trench was 1 μm. Under the same film growth conditions and basic parameters for each scheme, the following model was established (e.g. Figure 17 ).

[0145] Figure 17 The trench capacitor electrode structure of the present invention and the trench capacitor electrode structure of comparative example 2 (reference Figure 16 3D simulated warping cloud diagram of the trench capacitor electrode structure of the prior art shown in FIG.

[0146] Among them, (a), (b), and (c) are the three-dimensional simulated warping cloud diagrams of the trench capacitor electrode structures of Example 5, Example 7, and Example 2 of the present invention respectively; (d) is the three-dimensional simulated warping cloud diagram of Comparative Example 2 (reference Figure 16 3D simulation warping cloud map of the trench capacitor electrode structure (as shown).

[0147] Based on the above multiple models, stress and warpage simulation analysis is performed, and the warpage value under unit capacitance density is used to evaluate the influence of different model structures on device warpage. Figure 18 Results shown.

[0148] Figure 18 The graph of the change of unit capacitance density warpage value, where a, b, c, and d correspond to Figure 17 (a), (b), (c), and (d) are three-dimensional simulated warping cloud maps.

[0149] from Figure 18 It can be seen that the trench capacitor electrode structures (a, b, c), especially (a), of the present invention have better warpage control and a lower warpage value per unit capacitance density, which means that while maintaining high capacitance, the internal stress distribution of the device is more reasonable, which helps to improve high-frequency performance consistency, packaging compatibility and long-term reliability.

[0150] Compared with the prior art, the trench capacitor electrode structure and trench capacitor of the present invention, through the high-density element array on the first surface of the substrate and the arrangement design of the interconnection area, greatly improve the trench capacitor capacitance density, effectively increase the electrode surface area and optimize the electric field distribution, thereby improving the high-frequency characteristics of the device, significantly improving the electrical performance of the device, and improving the structural stability of the device.

[0151] The trench capacitor electrode structure and trench capacitor of the present invention innovatively integrate a large number of interconnection areas in a high-density cell array, greatly facilitating subsequent metal interconnection and improving process compatibility and device reliability.

[0152] The trench capacitor electrode structure and trench capacitor of the present invention, through a high-density array arrangement of primitive units with multiple rotational symmetries combined with the arrangement of interconnected areas, can allow for more uniform material deposition and filling, reduce gaps and cracks generated during the actual process of filling materials, and improve the quality and uniformity of the device.

[0153] The trench capacitor electrode structure and trench capacitor of the present invention can evenly distribute the load, reduce the concentration of stress, and provide better deadweight distribution by setting up primitive units with multiple rotational symmetries. In addition, when the primitive units with multiple rotational symmetries are affected by external temperature changes, the thermal expansion is more uniform, which can better prevent interface damage caused by differences in material expansion coefficients, thereby improving the stability and reliability of the device.

[0154] The trench capacitor electrode structure and the trench capacitor of the present invention can balance charge distribution, reduce leakage current, optimize electric field distribution, and improve device reliability by adjusting various parameters of the cell array and the interconnection area.

[0155] The trench capacitor electrode structure and trench capacitor of the present invention can shorten the current path, reduce resistance, and lower ESR (equivalent series resistance); by setting up a basic unit unit with multiple rotational symmetries, it can offset part of the parasitic inductance, improve high-frequency response characteristics, and reduce ESL (equivalent series inductance).

[0156] It will be apparent to those skilled in the art that the present invention is not limited to the details of the exemplary embodiments described above and that the invention can be embodied in other specific forms without departing from the spirit or essential characteristics of the invention. Therefore, the embodiments should be considered in all respects as illustrative and non-restrictive, and the scope of the invention is defined by the appended claims, not the foregoing description, and all variations within the meaning and range of equivalents of the claims are intended to be included therein. Any reference sign in a claim should not be construed as limiting the claim to which it relates.

[0157] In addition, it should be understood that although this specification is described in terms of implementation methods, not every implementation method contains only one independent technical solution. This narrative method of the specification is only for the sake of clarity. Those skilled in the art should regard the specification as a whole. The technical solutions in each embodiment can also be appropriately combined to form other implementation methods that can be understood by those skilled in the art.

Claims

1. A trench capacitor electrode structure, characterized in that: include: A substrate having a first surface comprising a plurality of periodically arranged interconnected regions; A primitive array is disposed on the first surface of the substrate, the primitive array comprising a plurality of primitive units arranged periodically, each of the primitive units corresponding to one of the interconnected regions, each of the primitive units comprising a plurality of primitive groups disposed around the corresponding interconnected region, each of the primitive groups comprising a plurality of strip-shaped primitives disposed in parallel; Wherein, each of the primitive units has multiple rotational symmetries.

2. The trench capacitor electrode structure according to claim 1, wherein: The multiple groups of primitive groups in each primitive unit have the same structure, and each primitive unit is formed by rotating any one of the primitive groups multiple times in a clockwise or counterclockwise direction with the interconnected area as the center point.

3. The trench capacitor electrode structure according to claim 1, wherein: Adjacent primitive units are arranged without overlapping; and / or adjacent primitive groups are arranged without overlapping.

4. The trench capacitor electrode structure according to claim 1, wherein: The primitive unit includes three groups of primitive groups with the same structure, and the three groups of primitive groups constitute a primitive unit with three-fold rotational symmetry.

5. The trench capacitor electrode structure according to claim 4, wherein: The three groups of primitive groups include a first primitive group, a second primitive group and a third primitive group arranged in a ring along the interconnected area; The first primitive group is arranged parallel to the first direction, the second primitive group is arranged parallel to the second direction, and the third primitive group is arranged parallel to the third direction, wherein the angle between the first direction, the second direction and the third direction is 120°.

6. The trench capacitor electrode structure according to claim 5, wherein: The first direction is a horizontal direction, or an angle between the first direction and the horizontal direction is θ1, and the range of θ1 is 0°~90°.

7. The trench capacitor electrode structure according to claim 5, wherein: The lengths L1 of the plurality of strip-shaped primitives in each group of the primitives are all equal.

8. The trench capacitor electrode structure according to claim 7, wherein: The plurality of strip-shaped primitives in each group of the primitives are arranged in a stepped manner in a direction away from the interconnection area.

9. The trench capacitor electrode structure according to claim 8, wherein: A line connecting the centers of the plurality of strip-shaped elements in the first element is parallel to the second direction, a line connecting the centers of the plurality of strip-shaped elements in the second element is parallel to the third direction, and a line connecting the centers of the plurality of strip-shaped elements in the third element is parallel to the first direction; or A center line connecting the plurality of strip elements in the first element is parallel to the third direction, a center line connecting the plurality of strip elements in the second element is parallel to the first direction, and a center line connecting the plurality of strip elements in the third element is parallel to the second direction.

10. The trench capacitor electrode structure according to claim 1, wherein: The primitive unit includes four primitive groups with the same structure, and the four primitive groups constitute a primitive unit with four-fold rotational symmetry.

11. The trench capacitor electrode structure according to claim 10, wherein: The four groups of primitive groups include a fourth primitive group, a fifth primitive group, a sixth primitive group and a seventh primitive group arranged in a ring along the interconnection area; The fourth primitive group and the sixth primitive group are arranged parallel to the first direction, and the fifth primitive group and the seventh primitive group are arranged parallel to the fourth direction, wherein the first direction is perpendicular to the fourth direction.

12. The trench capacitor electrode structure according to claim 11, wherein: One of the first direction and the fourth direction is a horizontal direction, and the other is a vertical direction; or, The angle between one of the first direction and the fourth direction and the horizontal direction is θ2, and the angle between the other of the first direction and the vertical direction is θ2, and the range of θ2 is 0°~90°.

13. The trench capacitor electrode structure according to claim 11, wherein: A vertical distance D between the top of the fourth primitive group and the top of the fifth primitive group in the fourth direction t greater than or equal to 0; and / or, The interconnection region has a preset length L0 in the fourth direction, and a vertical distance D between the bottom of the fourth primitive group and the bottom of the fifth primitive group in the fourth direction is b Greater than or equal to L0.

14. The trench capacitor electrode structure according to claim 11, wherein: The lengths L1 of the plurality of strip-shaped primitives in each group of the primitives are equal; and / or, The plurality of strip-shaped primitives in each group of the primitives are arranged in a stepped manner in a direction away from the interconnection area.

15. The trench capacitor electrode structure according to claim 1, wherein: The lengths L1 of the plurality of strip-shaped primitives in each group of the primitives are equal; and / or, The widths W1 of the plurality of strip-shaped primitives in each group of the primitives remain unchanged or gradually decrease or gradually increase in a direction away from the interconnected region; and / or, The distance D1 between adjacent strip-shaped primitives in each group of the primitives remains unchanged or gradually decreases or gradually increases in the direction away from the interconnected area; and / or, The plurality of strip-shaped primitives in each group of the primitives are arranged in a stepped manner in a direction away from the interconnection area.

16. The trench capacitor electrode structure according to claim 1, wherein: The strip-shaped element includes a column protruding from the first surface and / or a groove recessed in the first surface.

17. A trench capacitor, characterized in that: It comprises the trench capacitor electrode structure as described in any one of claims 1-16.

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