Hybrid bonding structure and method of manufacturing the same
By incorporating grooves and through-holes on the surface of the dielectric layer, the problems of bonding voids and low thermal reliability caused by tiny particles in the hybrid bonding structure are solved, achieving higher stability and reliability.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- NAT CENT FOR ADVANCED PACKAGING CO LTD
- Filing Date
- 2024-12-09
- Publication Date
- 2026-05-22
Smart Images
Figure CN119786475B_ABST
Abstract
Description
Technical Field
[0001] This invention relates to the field of semiconductor structure technology, and more specifically to a hybrid bonding structure and its preparation method. Background Technology
[0002] 3D integration technology is a crucial direction for continuously improving chip performance, and hybrid bonding technology is a key technology for realizing 3D chip stacking, playing an important role in technologies such as Chiplet, HBM, and CIS. Current hybrid bonding processes require strict control of contaminants (e.g., particles). During semiconductor packaging, substrate slicing generates particles, such as silicon debris, while tiny hard particles (typically smaller than 500 nm or less) are generated on the surface of the dielectric layer at the hybrid bonding interface. Research shows that particles as small as 1 μm can cause bonding voids of up to 10 mm, leading to bonding defects. Current standard cleaning operations can only remove particles larger than 1 μm; particles smaller than 1 μm cannot be removed by standard cleaning operations and remain on the semiconductor substrate and dielectric layer surface, easily appearing at the hybrid bonding interface, causing bonding voids within the hybrid bonding structure, ultimately leading to hybrid bonding failure.
[0003] One solution in related technologies is to create a dielectric cavity around the metal bumps of the hybrid bonding interface to accommodate the particles on the two opposing surfaces of the hybrid bonding interface. However, due to the cavity around the metal bumps, the metal bumps are very prone to expanding to the left and right during the annealing stage, while the expansion in the vertical direction is limited, which can easily lead to bonding voids. In addition, the pure cavity structure will result in low thermal reliability of the hybrid bonding structure. When heated, the air in the cavity expands, and the bonding interface is easily cracked, causing chip failure. Summary of the Invention
[0004] In view of this, the present invention provides a hybrid bonding structure and its preparation method to solve the problems in the related art, such as the presence of tiny hard particles on the surface of the dielectric layer at the hybrid bonding interface, which leads to bonding voids inside the hybrid bonding structure, and the presence of cavities inside the hybrid bonding structure, which leads to bonding voids and low thermal reliability.
[0005] In a first aspect, the present invention provides a hybrid bonding structure comprising:
[0006] First substrate;
[0007] A first bonding layer is located on one side surface of a first substrate. The first bonding layer includes a plurality of spaced-apart first metal layer units and a first dielectric layer on the side of the first metal layer units. The first dielectric layer has a first dielectric layer groove on its side surface facing away from the first substrate. The first dielectric layer groove is located between adjacent first metal layer units and at the pre-cut line position of the hybrid bonding structure. The pre-cut line position divides the hybrid bonding structure into a plurality of hybrid bonding structure units. Each hybrid bonding structure unit includes at least one first metal layer unit.
[0008] The second bonding layer is located on the surface of the first bonding layer facing away from the first substrate; the second bonding layer includes a plurality of spaced second metal layer units and a second dielectric layer on the side of the second metal layer units.
[0009] The first bonding layer and the second bonding layer are connected into a single structure by hybrid bonding; wherein the first dielectric layer and the second dielectric layer are in contact with each other and bonded together, and the first metal layer unit and the second metal layer unit are in contact with each other and bonded together.
[0010] The second substrate is located on the side surface of the second bonding layer that faces away from the first bonding layer.
[0011] The hybrid bonding structure provided by this invention, on the one hand, by providing a first dielectric layer groove on the side surface of the first dielectric layer facing away from the first substrate, can accommodate tiny particles on the surfaces of the first and second dielectric layers, reducing the impact of particles on the bonding interface, preventing void defects at the bonding interface, increasing the particle tolerance of the hybrid bonding interface, and improving the stability and reliability of the hybrid bonding structure; on the other hand, the first dielectric layer groove is located between adjacent first metal layer units and at the pre-cutting line position of the hybrid bonding structure, which is equivalent to reserving the void position outside the hybrid bonding structure unit (i.e., the unit containing the bonded metal layer and the side dielectric layer) formed after cutting, so that there are no voids inside the hybrid bonding structure unit formed after cutting, improving the thermal reliability of the hybrid bonding structure unit formed after cutting, preventing the formation of bonding voids, avoiding thermal expansion and cracking of the hybrid bonding structure unit formed after cutting, and thus improving the stability and reliability of the hybrid bonding structure unit formed after cutting. Therefore, the hybrid bonding structure provided by the present invention can increase the particle tolerance of the hybrid bonding interface, make the interior of the hybrid bonding structure void-free, improve the stability and reliability of the hybrid bonding structure, and thus improve the hybrid bonding yield; at the same time, it further makes the interior of the hybrid bonding unit formed after cutting void-free, improves the thermal reliability of the hybrid bonding structure unit formed after cutting, thereby improving the stability and reliability of the hybrid bonding structure unit formed after cutting.
[0012] In one alternative embodiment, the second dielectric layer has a second dielectric layer groove on the side surface facing away from the second substrate; the second dielectric layer groove is located between adjacent second metal layer units and at the pre-cut line position of the hybrid bonding structure.
[0013] The hybrid bonding structure provided by this invention features a second dielectric layer groove on the side surface of the second dielectric layer facing away from the second substrate. This groove, located between adjacent second metal layer units and at the pre-cutting line of the hybrid bonding structure, can accommodate minute particles from the surfaces of the first and second dielectric layers, further increasing the particle tolerance of the hybrid bonding interface. This eliminates voids within the hybrid bonding structure, improving its stability and reliability, and consequently increasing the hybrid bonding yield. Furthermore, it eliminates voids within the hybrid bonding units formed after cutting, enhancing the thermal reliability of the resulting hybrid bonding structure units, thereby improving their stability and reliability.
[0014] In one optional embodiment, the positions of the first dielectric layer groove and the second dielectric layer groove are perpendicularly corresponding, and the first dielectric layer groove and the second dielectric layer groove of the same position are located at the same pre-cut line position.
[0015] The hybrid bonding structure provided by this invention, by setting the positions of the first dielectric layer groove and the second dielectric layer groove to be perpendicularly aligned, and with the first and second dielectric layer grooves in the same group located at the same pre-cutting line, can vertically align and connect the first and second dielectric layer grooves to form a larger groove. This facilitates better accommodation of tiny particles on the surfaces of the first and second dielectric layers, further increasing the particle tolerance of the hybrid bonding interface, improving the stability and reliability of the hybrid bonding structure, and thus improving the hybrid bonding yield. At the same time, it can improve the thermal reliability of the hybrid bonding structure unit formed after cutting, thereby improving the stability and reliability of the hybrid bonding structure unit formed after cutting.
[0016] In one alternative embodiment, the positions of the first dielectric layer groove and the second dielectric layer groove do not correspond, and the first dielectric layer groove and the second dielectric layer groove are located at different pre-cutting line positions.
[0017] The hybrid bonding structure provided by this invention, by setting the positions of the first dielectric layer groove and the second dielectric layer groove to be non-corresponding, and the first dielectric layer groove and the second dielectric layer groove being located at different pre-cutting lines, can maximize the number of dielectric layer grooves at each pre-cutting line position, accommodating particles at different positions or regions on the surfaces of the first and second dielectric layers, further increasing the particle tolerance of the hybrid bonding interface, improving the stability and reliability of the hybrid bonding structure, and thus improving the hybrid bonding yield. At the same time, it can improve the thermal reliability of the hybrid bonding structure unit formed after cutting, thereby improving the stability and reliability of the hybrid bonding structure unit formed after cutting. In addition, it can also simplify the process flow and improve process efficiency.
[0018] In one alternative embodiment, the pre-cut line position corresponding to the first dielectric layer groove also has a first through hole; the first through hole penetrates the first substrate and the first dielectric layer, and extends into the first dielectric layer groove.
[0019] The hybrid bonding structure provided by this invention features a first through-hole positioned at a pre-cut line corresponding to the groove in the first dielectric layer. This first through-hole penetrates the first substrate and the first dielectric layer, extending into the groove. The first through-hole serves as a vent, allowing for the timely removal of various gaseous byproducts generated during annealing, reducing their impact on the hybrid structure and improving its reliability. Simultaneously, the location of the first through-hole at the pre-cut line ensures that the hybrid bonding structure unit formed after cutting is free of voids, enhancing its thermal reliability, preventing bonding voids, and avoiding thermal expansion and cracking of the hybrid bonding structure unit after cutting. This, in turn, improves the stability and reliability of the hybrid bonding structure unit formed after cutting.
[0020] In one optional embodiment, the pre-cut line position corresponding to the second dielectric layer groove also has a second through hole; the second through hole penetrates the second substrate and the second dielectric layer, and extends into the second dielectric layer groove.
[0021] The hybrid bonding structure provided by this invention features a second through-hole positioned at the pre-cut line location corresponding to the groove in the second dielectric layer. This second through-hole penetrates the second substrate and the second dielectric layer, extending into the groove of the second dielectric layer. The second through-hole serves as a vent, allowing for the timely removal of various gaseous byproducts generated during annealing, reducing their impact on the hybrid bonding structure and improving its reliability. Simultaneously, the second through-hole's location at the pre-cut line ensures that the hybrid bonding structure unit formed after cutting is free of voids, enhancing its thermal reliability, preventing bonding voids, and avoiding thermal expansion and cracking of the hybrid bonding structure unit after cutting. This, in turn, improves the stability and reliability of the hybrid bonding structure unit formed after cutting.
[0022] In one optional embodiment, the material of the first dielectric layer is SiO2, SiCN, or SiN; the material of the second dielectric layer is SiO2, SiCN, or SiN.
[0023] The diameter or width of the groove in the first dielectric layer is less than 50 μm to 100 μm; the depth of the groove in the first dielectric layer is 2 μm to 5 μm.
[0024] The diameter or width of the groove in the second dielectric layer is less than 50 μm to 100 μm; the depth of the groove in the second dielectric layer is 2 μm to 5 μm.
[0025] The diameter of the first through hole is less than 50 μm;
[0026] The diameter of the second through hole is less than 50 μm.
[0027] In a second aspect, the present invention provides a method for preparing a hybrid bonding structure, used to prepare the hybrid bonding structure of the first aspect described above, the method comprising:
[0028] Provide a first substrate;
[0029] A first bonding layer is formed on one side surface of a first substrate. The first bonding layer includes a plurality of spaced first metal layer units and a first dielectric layer on the side of the first metal layer units.
[0030] A first dielectric layer groove is formed on the side surface of the first dielectric layer facing away from the first substrate; the first dielectric layer groove is located between adjacent first metal layer units and at the pre-cut line position of the hybrid bonding structure; the pre-cut line position divides the hybrid bonding structure into multiple hybrid bonding structure units; each hybrid bonding structure unit includes at least one first metal layer unit;
[0031] Provide a second substrate;
[0032] A second bonding layer is formed on one side surface of the second substrate. The second bonding layer includes a plurality of spaced second metal layer units and a first dielectric layer on the side of the second metal layer units.
[0033] The first substrate and the second substrate are mixed and bonded together to form a mixed bonding structure; the first bonding layer and the second bonding layer are connected into an integral structure through mixed bonding; wherein the first dielectric layer and the second dielectric layer are in contact with each other and bonded together, and the first metal layer unit and the second metal layer unit are in contact with each other and bonded together.
[0034] The method for preparing a hybrid bonding structure provided by this invention, on the one hand, forms a first dielectric layer groove on the side surface of the first dielectric layer facing away from the first substrate, which can accommodate small particles on the surfaces of the first and second dielectric layers, reducing the influence of particles on the bonding interface, preventing void defects at the bonding interface of the hybrid bonding structure, increasing the particle tolerance of the hybrid bonding interface, and improving the stability and reliability of the hybrid bonding structure; on the other hand, the first dielectric layer groove is located between adjacent first metal layer units and at the pre-cutting line position of the hybrid bonding structure, which is equivalent to reserving the void position outside the hybrid bonding structure unit (i.e., the unit containing the bonded metal layer and the side dielectric layer) formed after cutting, so that there are no voids inside the hybrid bonding structure unit formed after cutting, improving the thermal reliability of the hybrid bonding structure unit formed after cutting, preventing the formation of bonding voids, avoiding thermal expansion and cracking of the hybrid bonding structure unit formed after cutting, and thus improving the stability and reliability of the hybrid bonding structure unit formed after cutting. Therefore, the hybrid bonding structure provided by the present invention can increase the particle tolerance of the hybrid bonding interface, make the interior of the hybrid bonding structure void-free, improve the stability and reliability of the hybrid bonding structure, and thus improve the hybrid bonding yield; at the same time, it further makes the interior of the hybrid bonding unit formed after cutting void-free, improves the thermal reliability of the hybrid bonding structure unit formed after cutting, thereby improving the stability and reliability of the hybrid bonding structure unit formed after cutting.
[0035] In one alternative embodiment, prior to the step of bonding the first substrate and the second substrate together, the method further includes:
[0036] A second dielectric layer groove is formed on the side surface of the second dielectric layer facing away from the second substrate; the second dielectric layer groove is located between adjacent second metal layer units and at the pre-cut position of the hybrid bonding structure.
[0037] In one alternative embodiment, after the step of forming a first dielectric layer groove on the side surface of the first dielectric layer facing away from the first substrate, the method includes: forming a first through hole at a pre-cut line position corresponding to the first dielectric layer groove; the first through hole penetrates the first substrate and the first dielectric layer and extends into the first dielectric layer groove;
[0038] And / or:
[0039] After the step of forming a second dielectric layer groove on the side surface of the second dielectric layer facing away from the second substrate, the method includes: forming a second through hole at the position of the pre-cut line corresponding to the second dielectric layer groove; the second through hole penetrates the second substrate and the second dielectric layer and extends into the second dielectric layer groove. Attached Figure Description
[0040] To more clearly illustrate the technical solutions in the specific embodiments or related technologies of the present invention, the drawings used in the description of the specific embodiments or related technologies will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.
[0041] Figure 1 This is a schematic diagram of a bonding structure in a related technology.
[0042] Figure 2 This is a schematic diagram of a hybrid bonding structure according to an embodiment of the present invention.
[0043] Figure 3 This is a top view of a hybrid bonding structure according to an embodiment of the present invention.
[0044] Figure 4 This is a schematic diagram of another hybrid bonding structure according to an embodiment of the present invention.
[0045] Figure 5 This is a schematic flowchart of a method for preparing a hybrid bonding structure according to an embodiment of the present invention.
[0046] Figure 6 This is a schematic diagram of a hybrid bonding structure forming a groove in the first dielectric layer in a method for preparing a hybrid bonding structure according to an embodiment of the present invention.
[0047] Figure 7 This is a schematic diagram of a hybrid bonding structure forming a second dielectric layer groove in a method for preparing a hybrid bonding structure according to an embodiment of the present invention.
[0048] Figure 8 In a method for preparing a hybrid bonding structure according to an embodiment of the present invention, in Figure 6 and Figure 7 A schematic diagram of a structure in which the first substrate and the second substrate are bonded together.
[0049] Figure 9 This is a schematic diagram of a hybrid bonding structure forming a groove in the first dielectric layer in a method for preparing a hybrid bonding structure according to an embodiment of the present invention.
[0050] Figure 10 This is a schematic diagram of a hybrid bonding structure forming a second dielectric layer groove in a method for preparing a hybrid bonding structure according to an embodiment of the present invention.
[0051] Figure 11 In a method for preparing a hybrid bonding structure according to an embodiment of the present invention, in Figure 9 and Figure 10A schematic diagram of a structure in which the first substrate and the second substrate are bonded together.
[0052] Figure 12 This is a schematic diagram of a specific process for preparing a hybrid bonding structure according to an embodiment of the present invention.
[0053] Figure 13 This is a schematic diagram of a specific process for preparing another hybrid bonding structure according to an embodiment of the present invention.
[0054] Figure label:
[0055] 1. Substrate; 2. Dielectric layer; 3. Metal bump; 4. Dielectric cavity; 11. First substrate; 12. First bonding layer; 121. First metal layer unit; 122. First dielectric layer; 13. First dielectric layer groove; 14. First via; 21. Second substrate; 22. Second bonding layer; 221. Second metal layer unit; 222. Second dielectric layer; 23. Second dielectric layer groove; 24. Second via; 30. Pre-cut line. Detailed Implementation
[0056] The present invention will now be described in further detail with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and not intended to limit it. Furthermore, it should be noted that, for ease of description, the accompanying drawings show only the parts relevant to the invention, not the entire structure.
[0057] In the following description, descriptions of well-known structures and techniques are omitted to avoid unnecessarily obscuring the concepts of the present invention. Various structural schematic diagrams according to embodiments of the present invention are shown in the accompanying drawings. These drawings are not to scale, and some details are enlarged for clarity, and some details may be omitted. The shapes of the various regions and layers shown in the drawings, as well as their relative sizes and positional relationships, are merely exemplary and may deviate in practice due to manufacturing tolerances or technical limitations. Furthermore, those skilled in the art can design regions / layers with different shapes, sizes, and relative positions as needed. In the context of the present invention, when a layer / element is referred to as being "on" another layer / element, the layer / element may be directly on the other layer / element, or there may be an intermediate layer / element between them. Additionally, if a layer / element is "on" another layer / element in one orientation, then when the orientation is reversed, the layer / element may be "below" the other layer / element.
[0058] 3D integration technology is a crucial direction for continuously improving chip performance, and hybrid bonding technology is a key technology for realizing 3D chip stacking, playing an important role in technologies such as Chiplet, HBM, and CIS. Current hybrid bonding processes require strict control of contaminants (e.g., particles). During semiconductor packaging, substrate slicing generates particles, such as silicon debris, while tiny hard particles (typically smaller than 500 nm or less) are generated on the surface of the dielectric layer at the hybrid bonding interface. Research shows that particles as small as 1 μm can cause bonding voids of up to 10 mm, leading to bonding defects. Current standard cleaning operations can only remove particles larger than 1 μm; particles smaller than 1 μm cannot be removed by standard cleaning operations and remain on the semiconductor substrate and dielectric layer surface, easily appearing at the hybrid bonding interface, causing bonding voids within the hybrid bonding structure, ultimately leading to hybrid bonding failure.
[0059] One solution in related technologies is as follows: Figure 1 As shown, the hybrid bonding structure is formed by bonding two identical upper and lower parts. In the formed bonding structure, the dielectric layer 2 and the metal bump 3 are located on the substrate 1. Dielectric cavities 4 are formed around the metal bump 3 at the hybrid bonding interface to accommodate particles on opposite surfaces of the upper and lower parts. However, due to the cavity around the metal bump 3, the metal bump is very prone to expanding laterally during the annealing stage, while the expansion in the vertical direction is limited, which can easily lead to bonding defects such as… Figure 1 The void situation shown means that the metal bumps 3 in the upper and lower parts are not bonded as expected, but are disconnected; in addition, the pure cavity structure will lead to low thermal reliability of the hybrid bonding structure. When heated, the air in the cavity expands, and the bonding interface is easily cracked, causing chip failure.
[0060] like Figure 2 As shown, this embodiment provides a hybrid bonding structure, which includes:
[0061] First substrate 11;
[0062] A first bonding layer 12 is located on one side surface of a first substrate 11. The first bonding layer 12 includes a plurality of spaced-apart first metal layer units 121 and a first dielectric layer 122 on the side of the first metal layer units 121. The first dielectric layer 122 has a first dielectric layer groove 13 on the side surface facing away from the first substrate 11. The first dielectric layer groove 13 is located between adjacent first metal layer units 121 and at the position of the pre-cut line 30 of the hybrid bonding structure. The pre-cut line 30 divides the hybrid bonding structure into a plurality of hybrid bonding structure units. Each hybrid bonding structure unit includes at least one first metal layer unit 121.
[0063] The second bonding layer 22 is located on the surface of the first bonding layer 12 facing away from the first substrate 11; the second bonding layer 22 includes a plurality of second metal layer units 221 arranged at intervals and a second dielectric layer 222 on the side of the second metal layer units 221.
[0064] The first bonding layer 12 and the second bonding layer 22 are connected to form an integral structure by hybrid bonding; wherein, the first dielectric layer 122 and the second dielectric layer 222 are in contact with each other and bonded together, and the first metal layer unit 121 and the second metal layer unit 221 are in contact with each other and bonded together.
[0065] The second substrate 21 is located on the side surface of the second bonding layer 22 that faces away from the first bonding layer 12.
[0066] In specific implementations, the materials of the first substrate 11 and the second substrate 21 can be silicon (Si), silicon-on-insulator (SOI), silicon carbide (SiC), silicon-germanium (SiGe), etc. The first dielectric layer groove 13 is adapted to accommodate tiny particles on the surfaces of the first dielectric layer 122 and the second dielectric layer 222. During the bonding process between the first bonding layer 12 and the second bonding layer 22, the tiny particles on the surfaces of the first dielectric layer 122 and the second dielectric layer 222 diffuse into the nearby first dielectric layer groove 13 along with the bonding wave.
[0067] Specifically, in some specific embodiments, the top view of the hybrid bonding structure is as follows: Figure 3 As shown, based on the hybrid bonding structure, the hybrid bonding structure can be divided into multiple hybrid bonding structure units along the pre-cut line 30 according to requirements; each hybrid bonding structure unit includes at least one first metal layer unit 121.
[0068] The hybrid bonding structure provided in this embodiment has two advantages. First, by providing a first dielectric layer groove on the side surface of the first dielectric layer facing away from the first substrate, it can accommodate tiny particles on the surfaces of the first and second dielectric layers, reducing the impact of particles on the bonding interface, preventing void defects at the bonding interface, increasing the particle tolerance of the hybrid bonding interface, and improving the stability and reliability of the hybrid bonding structure. Second, the first dielectric layer groove is located between adjacent first metal layer units and at the pre-cutting line position of the hybrid bonding structure. This is equivalent to reserving the void position outside the hybrid bonding structure unit (i.e., the unit containing the bonded metal layer and the side dielectric layer) formed after cutting. This ensures that the interior of the hybrid bonding structure unit formed after cutting is free of voids, improving the thermal reliability of the hybrid bonding structure unit formed after cutting, preventing the formation of bonding voids, and avoiding thermal expansion and cracking of the hybrid bonding structure unit formed after cutting, thereby improving the stability and reliability of the hybrid bonding structure unit formed after cutting. Therefore, the hybrid bonding structure provided by the present invention can increase the particle tolerance of the hybrid bonding interface, make the interior of the hybrid bonding structure void-free, improve the stability and reliability of the hybrid bonding structure, and thus improve the hybrid bonding yield; at the same time, it further makes the interior of the hybrid bonding unit formed after cutting void-free, improves the thermal reliability of the hybrid bonding structure unit formed after cutting, thereby improving the stability and reliability of the hybrid bonding structure unit formed after cutting.
[0069] In some alternative implementations, such as Figure 2 As shown, the second dielectric layer 222 has a second dielectric layer groove 23 on the side surface facing away from the second substrate 21; the second dielectric layer groove 23 is located between adjacent second metal layer units 221 and at the position of the pre-cut line 30 of the hybrid bonding structure.
[0070] The hybrid bonding structure provided in this embodiment has a second dielectric layer groove on the side surface of the second dielectric layer facing away from the second substrate. The second dielectric layer groove is located between adjacent second metal layer units and at the pre-cutting line position of the hybrid bonding structure. It can accommodate small particles on the surfaces of the first and second dielectric layers, further increasing the particle tolerance of the hybrid bonding interface, making the interior of the hybrid bonding structure void-free, improving the stability and reliability of the hybrid bonding structure, and thus improving the hybrid bonding yield. At the same time, it further makes the interior of the hybrid bonding unit formed after cutting void-free, improving the thermal reliability of the hybrid bonding structure unit formed after cutting, thereby improving the stability and reliability of the hybrid bonding structure unit formed after cutting.
[0071] In some optional embodiments, the positions of the first dielectric layer groove 13 and the second dielectric layer groove 23 are perpendicularly corresponding, and the first dielectric layer groove 13 and the second dielectric layer groove 23 of the same position are located at the same pre-cut line position.
[0072] The hybrid bonding structure provided in this embodiment, by setting the positions of the first dielectric layer groove and the second dielectric layer groove to be perpendicularly aligned, and the first and second dielectric layer grooves in the same group corresponding to each other being located at the same pre-cutting line, can make the first and second dielectric layer grooves perpendicularly aligned and connected, forming a larger groove. This is beneficial for better accommodating the tiny particles on the surfaces of the first and second dielectric layers, further increasing the particle tolerance of the hybrid bonding interface, improving the stability and reliability of the hybrid bonding structure, and thus improving the hybrid bonding yield. At the same time, it can improve the thermal reliability of the hybrid bonding structure unit formed after cutting, thereby improving the stability and reliability of the hybrid bonding structure unit formed after cutting.
[0073] In some alternative embodiments, the positions of the first dielectric layer groove 13 and the second dielectric layer groove 23 do not correspond, and the first dielectric layer groove 13 and the second dielectric layer groove 23 are located at different pre-cut lines 30.
[0074] The hybrid bonding structure provided in this embodiment, by setting the positions of the first dielectric layer groove and the second dielectric layer groove to be non-corresponding, and the first dielectric layer groove and the second dielectric layer groove being located at different pre-cutting lines, can maximize the number of dielectric layer grooves at each pre-cutting line position, accommodating particles at different positions or regions on the surfaces of the first and second dielectric layers, further increasing the particle tolerance of the hybrid bonding interface, improving the stability and reliability of the hybrid bonding structure, and thus improving the hybrid bonding yield. At the same time, it can improve the thermal reliability of the hybrid bonding structure unit formed after cutting, thereby improving the stability and reliability of the hybrid bonding structure unit formed after cutting. In addition, it can also simplify the process flow and improve process efficiency.
[0075] In some alternative implementations, such as Figure 4 As shown, the position of the pre-cut line 30 corresponding to the first dielectric layer groove 13 also has a first through hole 14; the first through hole 14 penetrates the first substrate 11 and the first dielectric layer 122, and extends into the first dielectric layer groove 13.
[0076] The hybrid bonding structure provided in this embodiment features a first through-hole positioned at the pre-cut line corresponding to the groove in the first dielectric layer. This first through-hole penetrates the first substrate and the first dielectric layer, extending into the groove. The first through-hole serves as a vent, allowing for the timely removal of various gaseous byproducts generated during annealing, reducing their impact on the hybrid structure and improving its reliability. Simultaneously, the location of the first through-hole at the pre-cut line ensures that the hybrid bonding structure unit formed after cutting is free of voids, enhancing its thermal reliability, preventing bonding voids, and avoiding thermal expansion and cracking of the hybrid bonding structure unit after cutting. This, in turn, improves the stability and reliability of the hybrid bonding structure unit formed after cutting.
[0077] In some alternative implementations, such as Figure 4 As shown, the second through hole 24 is also located at the pre-cut line 30 position corresponding to the second dielectric layer groove 23; the second through hole 24 penetrates the second substrate 21 and the second dielectric layer 222 and extends into the second dielectric layer groove 23.
[0078] The hybrid bonding structure provided in this embodiment features a second through-hole positioned at the pre-cut line corresponding to the groove in the second dielectric layer. This second through-hole penetrates the second substrate and the second dielectric layer, extending into the groove of the second dielectric layer. The second through-hole serves as a vent, allowing for the timely removal of various gaseous byproducts generated during annealing, reducing their impact on the hybrid bonding structure and improving its reliability. Simultaneously, the second through-hole's location at the pre-cut line ensures that the hybrid bonding structure unit formed after cutting is free of voids, enhancing its thermal reliability, preventing bonding voids, and avoiding thermal expansion and cracking of the hybrid bonding structure unit after cutting. This, in turn, improves the stability and reliability of the hybrid bonding structure unit formed after cutting.
[0079] In some optional embodiments, the material of the first dielectric layer 122 is SiO2, SiCN, or SiN; the material of the second dielectric layer 222 is SiO2, SiCN, or SiN;
[0080] The diameter or width of the first dielectric layer groove 13 is less than 50μm to 100μm, for example 50μm, 70μm, 80μm, 90μm or 100μm; the depth of the first dielectric layer groove 13 is 2μm to 5μm, for example 2μm, 3μm, 4μm or 5μm.
[0081] The diameter or width of the second dielectric layer groove 23 is less than 50μm to 100μm, for example 50μm, 70μm, 80μm, 90μm or 100μm; the depth of the second dielectric layer groove 23 is 2μm to 5μm, for example 2μm, 3μm, 4μm or 5μm.
[0082] The diameter of the first through hole 14 is less than 50 μm, for example, 10 μm, 20 μm, 30 μm or 40 μm;
[0083] The diameter of the second through hole 24 is less than 50 μm, for example, 10 μm, 20 μm, 30 μm or 40 μm.
[0084] like Figure 5 As shown, this embodiment provides a method for preparing a hybrid bonding structure, which includes, but is not limited to, steps S101 to S106.
[0085] Step S101: Provide a first substrate;
[0086] Step S102: A first bonding layer is formed on one side surface of the first substrate. The first bonding layer includes a plurality of spaced first metal layer units and a first dielectric layer on the side of the first metal layer units.
[0087] Step S103: A first dielectric layer groove is formed on the side surface of the first dielectric layer facing away from the first substrate, such as... Figure 6 As shown; the first dielectric layer groove is located between adjacent first metal layer units and at the pre-cut line position of the hybrid bonding structure; the pre-cut line position divides the hybrid bonding structure into multiple hybrid bonding structure units; each hybrid bonding structure unit includes at least one first metal layer unit;
[0088] Step S104: Provide a second substrate;
[0089] Step S105: A second bonding layer is formed on one side surface of the second substrate. The second bonding layer includes a plurality of spaced second metal layer units and a second dielectric layer on the side of the second metal layer units.
[0090] Step S106: The first substrate and the second substrate are mixed and bonded together to form a mixed bonding structure, such as... Figure 8 As shown, the first bonding layer and the second bonding layer are connected into an integral structure by hybrid bonding; wherein, the first dielectric layer and the second dielectric layer are in contact with each other and bonded together, and the first metal layer unit and the second metal layer unit are in contact with each other and bonded together.
[0091] In specific implementation, the method of forming the first dielectric layer groove on the side surface of the first dielectric layer facing away from the first substrate can be etching, drilling, cutting or other grooving processes. The specific method can be selected according to the actual situation, and this embodiment does not limit it.
[0092] The method for preparing the hybrid bonding structure provided in this embodiment has two advantages. First, by forming a first dielectric layer groove on the side surface of the first dielectric layer facing away from the first substrate, it can accommodate small particles on the surfaces of the first and second dielectric layers, reducing the impact of particles on the bonding interface, preventing void defects at the bonding interface, increasing the particle tolerance of the hybrid bonding interface, and improving the stability and reliability of the hybrid bonding structure. Second, the first dielectric layer groove is located between adjacent first metal layer units and at the pre-cutting line position of the hybrid bonding structure. This is equivalent to reserving the void position outside the hybrid bonding structure unit (i.e., the unit containing the bonded metal layer and the side dielectric layer) formed after cutting. This ensures that the interior of the hybrid bonding structure unit formed after cutting is free of voids, improving the thermal reliability of the hybrid bonding structure unit formed after cutting, preventing the formation of bonding voids, and avoiding thermal expansion and cracking of the hybrid bonding structure unit formed after cutting, thereby improving the stability and reliability of the hybrid bonding structure unit formed after cutting. Therefore, the hybrid bonding structure provided by the present invention can increase the particle tolerance of the hybrid bonding interface, make the interior of the hybrid bonding structure void-free, improve the stability and reliability of the hybrid bonding structure, and thus improve the hybrid bonding yield; at the same time, it further makes the interior of the hybrid bonding unit formed after cutting void-free, improves the thermal reliability of the hybrid bonding structure unit formed after cutting, thereby improving the stability and reliability of the hybrid bonding structure unit formed after cutting.
[0093] In one alternative implementation, such as Figure 7 As shown, prior to the step of mixing and bonding the first substrate and the second substrate together, the method further includes:
[0094] A second dielectric layer groove is formed on the side surface of the second dielectric layer facing away from the second substrate; the second dielectric layer groove is located between adjacent second metal layer units and at the pre-cut position of the hybrid bonding structure.
[0095] The hybrid bonding structure provided in this embodiment forms a second dielectric layer groove on the side surface of the second dielectric layer facing away from the second substrate. The second dielectric layer groove is located between adjacent second metal layer units and at the pre-cutting line position of the hybrid bonding structure. It can accommodate small particles on the surfaces of the first and second dielectric layers, further increasing the particle tolerance of the hybrid bonding interface, making the interior of the hybrid bonding structure void-free, improving the stability and reliability of the hybrid bonding structure, and thus improving the hybrid bonding yield. At the same time, it further makes the interior of the hybrid bonding unit formed after cutting void-free, improving the thermal reliability of the hybrid bonding structure unit formed after cutting, thereby improving the stability and reliability of the hybrid bonding structure unit formed after cutting.
[0096] In one alternative implementation, such as Figure 9As shown, after the step of forming a first dielectric layer groove on the side surface of the first dielectric layer facing away from the first substrate, the method includes: forming a first through hole at the position of the pre-cut line corresponding to the first dielectric layer groove; the first through hole penetrates the first substrate and the first dielectric layer and extends into the first dielectric layer groove;
[0097] And / or:
[0098] like Figure 10 As shown, after the step of forming a second dielectric layer groove on the side surface of the second dielectric layer facing away from the second substrate, the method includes: forming a second through hole at the position of the pre-cut line corresponding to the second dielectric layer groove; the second through hole penetrates the second substrate and the second dielectric layer and extends into the second dielectric layer groove.
[0099] The hybrid bonding structure provided in this embodiment can serve as a venting mechanism by setting a first through hole and / or a second through hole, which can promptly discharge various gaseous byproducts generated during the annealing process, reducing their impact on the hybrid structure and improving its reliability. Simultaneously, the first through hole and / or the second through hole are located at the pre-cutting line of the hybrid bonding structure, ensuring that the interior of the hybrid bonding structure unit formed after cutting is free of voids. This improves the thermal reliability of the hybrid bonding structure unit formed after cutting, prevents the formation of bonding voids, and avoids thermal expansion and cracking of the hybrid bonding structure unit formed after cutting, thereby improving the stability and reliability of the hybrid bonding structure unit formed after cutting.
[0100] like Figure 12 As shown, the present invention also provides a schematic flowchart of a method for preparing a hybrid bonding structure, including the following steps:
[0101] Step S201, provide a first substrate;
[0102] Step S202: A first bonding layer is formed on one side surface of the first substrate. The first bonding layer includes a plurality of spaced first metal layer units and a first dielectric layer on the side of the first metal layer units.
[0103] Step S203: A first dielectric layer groove is formed on the side surface of the first dielectric layer facing away from the first substrate, such as... Figure 6 As shown; the first dielectric layer groove is located between adjacent first metal layer units and at the pre-cut line position of the hybrid bonding structure; the pre-cut line position divides the hybrid bonding structure into multiple hybrid bonding structure units; each hybrid bonding structure unit includes at least one first metal layer unit;
[0104] Step S204: Provide a second substrate;
[0105] Step S205: A second bonding layer is formed on one side surface of the second substrate. The second bonding layer includes a plurality of spaced second metal layer units and a second dielectric layer on the side of the second metal layer units.
[0106] Step S206: A second dielectric layer groove is formed on the side surface of the second dielectric layer facing away from the second substrate, such as... Figure 7 As shown; the second dielectric layer groove is located between adjacent second metal layer units and at the pre-cut position of the hybrid bonding structure;
[0107] Step S207: The first substrate and the second substrate are mixed and bonded together to form a mixed bonding structure, such as... Figure 8 As shown, the first bonding layer and the second bonding layer are connected into an integral structure by hybrid bonding; wherein, the first dielectric layer and the second dielectric layer are in contact with each other and bonded together, and the first metal layer unit and the second metal layer unit are in contact with each other and bonded together.
[0108] like Figure 13 As shown, the present invention also provides a schematic flowchart of another method for preparing a hybrid bonding structure, including the following steps:
[0109] Step S301, provide a first substrate;
[0110] Step S302: A first bonding layer is formed on one side surface of the first substrate. The first bonding layer includes a plurality of spaced first metal layer units and a first dielectric layer on the side of the first metal layer units.
[0111] Step S303: A first dielectric layer groove is formed on the side surface of the first dielectric layer facing away from the first substrate; the first dielectric layer groove is located between adjacent first metal layer units and at the pre-cut line position of the hybrid bonding structure; the pre-cut line position divides the hybrid bonding structure into multiple hybrid bonding structure units; each hybrid bonding structure unit includes at least one first metal layer unit;
[0112] Step S304: A first through hole is formed at the pre-cut line position corresponding to the groove in the first dielectric layer, such as... Figure 9 As shown; the first via penetrates the first substrate and the first dielectric layer, and extends into the groove of the first dielectric layer;
[0113] Step S305, provide a second substrate;
[0114] Step S306: A second bonding layer is formed on one side surface of the second substrate. The second bonding layer includes a plurality of spaced second metal layer units and a second dielectric layer on the side of the second metal layer units.
[0115] Step S307: A second dielectric layer groove is formed on the side surface of the second dielectric layer facing away from the second substrate; the second dielectric layer groove is located between adjacent second metal layer units and at the pre-cut position of the hybrid bonding structure;
[0116] Step S308: A second through hole is formed at the pre-cut line position corresponding to the groove in the second dielectric layer, such as... Figure 10 As shown; the second via penetrates the second substrate and the second dielectric layer, and extends into the groove of the second dielectric layer.
[0117] Step S309: The first substrate and the second substrate are mixed and bonded together to form a mixed bonding structure, such as... Figure 11 As shown, the first bonding layer and the second bonding layer are connected into an integral structure by hybrid bonding; wherein, the first dielectric layer and the second dielectric layer are in contact with each other and bonded together, and the first metal layer unit and the second metal layer unit are in contact with each other and bonded together.
[0118] In the description of this specification, the references to terms such as "this embodiment," "an embodiment," "some embodiments," "example," "specific example," or "some examples," etc., refer to specific features, structures, materials, or characteristics described in connection with that embodiment or example, which are included in at least one embodiment or example of the present invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples. Furthermore, those skilled in the art can combine and integrate the different embodiments or examples described in this specification and the features of different embodiments or examples without contradiction. Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of the present invention, "a plurality of" means at least two, such as two, three, etc., unless otherwise explicitly specified.
[0119] The above description does not provide detailed explanations of the technical aspects of each layer's patterning, etching, etc. However, those skilled in the art should understand that various technical means can be used to form layers and regions of the desired shape. Furthermore, to form the same structure, those skilled in the art can also design methods that are not entirely identical to those described above. Additionally, although various embodiments have been described above, this does not mean that the measures in the various embodiments cannot be used advantageously in combination.
[0120] The above description is merely a preferred embodiment of the present invention and the technical principles employed. Those skilled in the art will understand that the present invention is not limited to the specific embodiments described above, and various obvious changes, readjustments, combinations, and substitutions can be made without departing from the scope of protection of the present invention. Therefore, although the present invention has been described in detail through the above embodiments, the present invention is not limited to the above embodiments, and may include many other equivalent embodiments without departing from the concept of the present invention. The scope of protection of the present invention is determined by the scope of the appended claims.
Claims
1. A hybrid bonding structure, characterized in that, The hybrid bonding structure includes: First substrate; A first bonding layer is located on one side surface of the first substrate. The first bonding layer includes a plurality of spaced-apart first metal layer units and a first dielectric layer on the side of the first metal layer units. The first dielectric layer has a first dielectric layer groove on its side surface facing away from the first substrate. The depth of the first dielectric layer groove is less than the thickness of the first dielectric layer. The first dielectric layer groove is located between adjacent first metal layer units and at the pre-cut line position of the hybrid bonding structure. The pre-cut line position divides the hybrid bonding structure into a plurality of hybrid bonding structure units. Each hybrid bonding structure unit includes at least one first metal layer unit, and the first dielectric layer groove is located outside the edge of the hybrid bonding structure unit. The second bonding layer is located on the surface of the first bonding layer facing away from the first substrate; the second bonding layer includes a plurality of spaced-apart second metal layer units and a second dielectric layer on the side of the second metal layer units. The first bonding layer and the second bonding layer are connected to form an integral structure by hybrid bonding; wherein, the first dielectric layer and the second dielectric layer are in contact with each other and bonded together, and the first metal layer unit and the second metal layer unit are in contact with each other and bonded together; Second substrate; located on the side surface of the second bonding layer opposite to the first bonding layer; The second dielectric layer has a second dielectric layer groove on the side surface facing away from the second substrate; the depth of the second dielectric layer groove is less than the thickness of the second dielectric layer; the second dielectric layer groove is located between adjacent second metal layer units and at the pre-cut line position of the hybrid bonding structure; The positions of the first dielectric layer groove and the second dielectric layer groove are perpendicularly corresponding, and the first dielectric layer groove and the second dielectric layer groove in the same group are located at the same pre-cutting line position; the interior of the hybrid bonding structure unit formed after cutting has no gaps.
2. The hybrid bonding structure according to claim 1, characterized in that, The pre-cut line position corresponding to the first dielectric layer groove also has a first through hole; the first through hole penetrates the first substrate and the first dielectric layer, and extends into the first dielectric layer groove.
3. The hybrid bonding structure according to claim 2, characterized in that, The pre-cut line position corresponding to the second dielectric layer groove also has a second through hole; the second through hole penetrates the second substrate and the second dielectric layer, and extends into the second dielectric layer groove.
4. The hybrid bonding structure according to claim 3, characterized in that, The material of the first dielectric layer is SiO2, SiCN, or SiN; the material of the second dielectric layer is SiO2, SiCN, or SiN. The diameter or width of the first dielectric layer groove is 50μm to 100μm; the depth of the first dielectric layer groove is 2μm to 5μm. The diameter or width of the second dielectric layer groove is 50μm to 100μm; the depth of the second dielectric layer groove is 2μm to 5μm. The diameter of the first through hole is less than 50 μm; The diameter of the second through hole is less than 50 μm.
5. A method for preparing a hybrid bonding structure, used to prepare the hybrid bonding structure as described in claim 1, characterized in that, Provide a first substrate; A first bonding layer is formed on one side surface of the first substrate. The first bonding layer includes a plurality of spaced first metal layer units and a first dielectric layer on the side of the first metal layer units. A first dielectric layer groove is formed on the surface of the first dielectric layer facing away from the first substrate; the depth of the first dielectric layer groove is less than the thickness of the first dielectric layer; the first dielectric layer groove is located between adjacent first metal layer units and at the pre-cut line position of the hybrid bonding structure; the pre-cut line position divides the hybrid bonding structure into multiple hybrid bonding structure units; each hybrid bonding structure unit includes at least one first metal layer unit, and the first dielectric layer groove is located outside the edge of the hybrid bonding structure unit; Provide a second substrate; A second bonding layer is formed on one side surface of the second substrate. The second bonding layer includes a plurality of spaced second metal layer units and a second dielectric layer on the side of the second metal layer units. The first substrate and the second substrate are mixed and bonded together to form a mixed bonding structure; the first bonding layer and the second bonding layer are connected into an integral structure through mixed bonding; wherein, the first dielectric layer and the second dielectric layer are correspondingly contacted and bonded together, and the first metal layer unit and the second metal layer unit are correspondingly contacted and bonded together. Before the step of mixing and bonding the first substrate and the second substrate together, the method further includes: A second dielectric layer groove is formed on the side surface of the second dielectric layer facing away from the second substrate; the depth of the second dielectric layer groove is less than the thickness of the second dielectric layer; the second dielectric layer groove is located between adjacent second metal layer units and at the pre-cut position of the hybrid bonding structure; wherein, the positions of the first dielectric layer groove and the second dielectric layer groove are perpendicularly corresponding, and the first dielectric layer groove and the second dielectric layer groove in the same group corresponding to the positions are located at the same pre-cut line position; the hybrid bonding structure unit formed after cutting has no gaps inside.
6. The method for preparing the hybrid bonding structure according to claim 5, characterized in that, The step of forming a first dielectric layer groove on the side surface of the first dielectric layer facing away from the first substrate includes: forming a first through hole at a pre-cut line position corresponding to the first dielectric layer groove; the first through hole penetrates the first substrate and the first dielectric layer and extends into the first dielectric layer groove; And / or: The step of forming a second dielectric layer groove on the side surface of the second dielectric layer opposite to the second substrate includes: forming a second through hole at the pre-cut line position corresponding to the second dielectric layer groove; the second through hole penetrates the second substrate and the second dielectric layer and extends into the second dielectric layer groove.