Joint structure

Abstract

The utility model provides a joint structure. The joint structure comprises a first electric connecting piece and a second electric connecting piece, the first electric connector comprises a connecting surface, a first conductive connecting bulge and a first polymer layer, the first conductive connecting bulge protrudes out of the connecting surface of the first electric connector, the first conductive connecting bulge is provided with a first strip-shaped branch embedded into the first polymer layer, and the first polymer layer surrounds the peripheral side surface of the first electric connector and laterally covers the first conductive connecting bulge. According to the embodiment of the invention, the bonding structure comprises the first conductive connection projection, and the first conductive connection projection is provided with the first strip-shaped branch embedded into the first polymer layer, so that the bonding strength of the first conductive connection projection and the first polymer layer can be improved, and a contribution can be made for enhancing the bonding strength of the bonding structure; therefore, the reliability of the joint structure is improved.

Description

Technical Field

[0001] The present application relates to the field of semiconductor technology, and more particularly, to a bonding structure. Background Art

[0002] In recent years, the introduction of system-on-chip (SoIC) technology has made copper-to-copper direct bonding a key technology for connecting the dots between ultra-high-density transistor chips. Currently, copper-to-copper direct bonding can be performed by grinding copper using a chemical mechanical polishing (CMP) process, but the CMP machine is expensive and has high manufacturing costs. Figure 1 1 is a cross-sectional schematic diagram of a method for preparing a nanowire bonding structure 10 in the prior art. Figure 1 As shown, the current copper-to-copper nanowire bonding structure 10 has gaps between the side walls of multiple nanowires 11 due to the compression of the nanowires 11 when the nanowires 11 are bonded. Therefore, the current nanowire bonding will cause more pores, resulting in poor electrical properties after the hybrid bond bonding. Figure 2 FIG. 2 is a schematic cross-sectional view of a nanowire bonding structure 20 after a metal layer 13 is filled in the prior art. Figure 2 As shown, generally speaking, the metal layer 13 can be filled before or after the nanowires are joined to increase the metal filling rate, but this will increase the process cost and the output per hour (Units Per Hour, UPH) is also lower. For example, when using the template method to prepare copper nanowires, the template material needs to be removed from the copper nanowires, which takes a lot of time and money. In addition, the current bonding structure has poor bonding strength and low reliability. Utility Model Content

[0003] In view of the above problems existing in the prior art, an embodiment of the present application proposes a bonding structure, which can at least enhance the bonding strength of the bonding structure and improve the reliability of the bonding structure.

[0004] According to one aspect of the present application, a bonding structure is provided, which includes: a first electrical connector; a first conductive connection protrusion and a first polymer layer, the first conductive connection protrusion protruding from the connection surface of the first electrical connector, the first conductive connection protrusion having a first strip branch embedded in the first polymer layer, and the first polymer layer surrounding the peripheral side of the first electrical connector and laterally covering the first conductive connection protrusion.

[0005] In one or more embodiments, the first conductive connection protrusion is a first dendrite connection structure composed of multiple dendrites grown on the connection surface of the first electrical connector, the first dendrite connection structure has a first dendrite in contact with the first polymer layer, the first dendrite includes a first main body connected to the first electrical connector and a first branch branched from the first main body and embedded in the first polymer layer, the first branch constitutes a first strip branch.

[0006] In one or more embodiments, the first dendrite further includes a third branch branching from the first branch, and the third branch is embedded in the first polymer layer.

[0007] In one or more embodiments, there is a gap between the first body and the first polymer layer, and a vertical projection of the first branch onto the first body overlaps with a vertical projection of the gap onto the first body.

[0008] In one or more embodiments, the joining structure also includes: a second conductive connection protrusion and a second electrical connector arranged above and below the first electrical connector, the second conductive connection protrusion protruding from a connection surface of the second electrical connector; a second polymer layer, the second polymer layer surrounding the peripheral side surface of the second electrical connector and laterally covering the second conductive connection protrusion, wherein the first conductive connection protrusion is electrically connected face to face to the second conductive connection protrusion, and the second conductive connection protrusion has a second strip branch embedded in the second polymer layer.

[0009] In one or more embodiments, the second conductive connection protrusion is a second dendrite connection structure composed of multiple dendrites grown on the connection surface of the second electrical connector, the second dendrite connection structure has a second dendrite in contact with the second polymer layer, the second dendrite includes a second body connected to the second electrical connector and a second branch branched from the second body and embedded in the second polymer layer, the second branch constitutes a second strip branch.

[0010] In one or more embodiments, the first conductive connection protrusion is a first dendrite connection structure formed by multiple dendrites grown on the connection surface of the first electrical connector, the first dendrite connection structure has a first dendrite in contact with the first polymer layer, the first dendrite includes a first main body connected to the first electrical connector and multiple first branches branching from the first main body, one of the multiple first branches is embedded in the first polymer layer and another one is embedded in the second polymer layer together with the second branch.

[0011] In one or more embodiments, the second dendrite connecting structure has a first sub-portion entering into the first dendrite connecting structure, the first dendrite connecting structure has a second sub-portion entering into the second dendrite connecting structure, and the first sub-portion and the second sub-portion contact each other.

[0012] In one or more embodiments, the side surface of the first electrical connector is staggered or aligned with the side surface of the second electrical connector.

[0013] In one or more embodiments, the top surface of the first polymer layer and the connection surface of the first electrical connector are located on the same side of the first electrical connector, the top surface of the second polymer layer and the connection surface of the second electrical connector are located on the same side of the second electrical connector, and the top surface of the first polymer layer and the top surface of the second polymer layer are directly bonded together.

[0014] In one or more embodiments, the second dendrite connection structure has a portion entering into the first polymer layer.

[0015] In one or more embodiments, the first electrical connection member and the second electrical connection member are both pads.

[0016] In one or more embodiments, the bonding structure further includes a third electrical connector electrically connected to the first electrical connector, and the third electrical connector and the first conductive connection protrusion are located on opposite sides of the first electrical connector.

[0017] In one or more embodiments, the first polymer layer further surrounds a peripheral side of the third electrical connection component.

[0018] In one or more embodiments, the third electrical connection is a copper pillar.

[0019] In one or more embodiments, the first body and the first branch are both cylindrical, and the diameter of the first body is larger than the diameter of the first branch.

[0020] According to another aspect of the present application, another bonding structure is provided, which can at least enhance the bonding strength of the bonding structure and improve the reliability of the bonding structure, and the other bonding structure includes: a first electrical connector; a first polymer layer, which surrounds the peripheral side of the first electrical connector and the top surface of the first polymer layer is higher than the connection surface of the first electrical connector; a first conductive connection protrusion, which protrudes from the connection surface of the first electrical connector and is electrically connected to the first electrical connector, and the first conductive connection protrusion has a portion located in the space formed by the first electrical connector and the first polymer layer, and a first strip branch embedded in the first polymer layer.

[0021] In one or more embodiments, the first electrical connection member is a cylindrical copper pad.

[0022] In one or more embodiments, a highest point of the first conductive connection protrusion compared to a connection surface of the first electrical connection member is aligned with a top surface of the first polymer layer.

[0023] In one or more embodiments, the first polymer layer is a polyimide layer.

[0024] The beneficial technical effects of the utility model are:

[0025] The bonding structure of an embodiment of the present application includes a first conductive connection protrusion, which has a first strip branch embedded in the first polymer layer, which can increase the bonding strength between the first conductive connection protrusion and the first polymer layer, and further contribute to enhancing the bonding strength of the bonding structure to improve the reliability of the bonding structure. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the prior art, the drawings required for use in the embodiments are briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can also be obtained based on these drawings without creative work. It is worth noting that according to the standard practice of the industry, the various components are not drawn to scale and are only used for illustration purposes. In fact, for the clarity of discussion, the size of each component can be arbitrarily increased or reduced.

[0027] Figure 1 It is a cross-sectional schematic diagram of the preparation of nanowire bonding structure in the prior art.

[0028] Figure 2 It is a schematic cross-sectional view of a nanowire bonding structure after a metal layer is filled in the prior art.

[0029] Figure 3 is a schematic cross-sectional view of a bonding structure according to an embodiment of the present application.

[0030] Figure 4 is a schematic cross-sectional view of a bonding structure according to another embodiment of the present application.

[0031] Figure 5 yes Figure 4 and Figure 6 An enlarged schematic diagram of area A in FIG.

[0032] Figure 6 is a schematic cross-sectional view of a bonding structure according to another embodiment of the present application.

[0033] Figure 7 yes Figure 6 An enlarged schematic diagram of area B in FIG.

[0034] Figure 8 yes Figure 6 An enlarged schematic diagram of area C in FIG.

[0035] Fig. 9 is a schematic cross-sectional view of a bonding structure not including a first polymer layer according to an embodiment of the present application.

[0036] Fig.10 yes Fig. 9 The schematic diagram is a state diagram of the engagement structure being wound with the fixing belt after the engagement structure is rotated 90° clockwise.

[0037] Fig.11A It is overlooking Fig.10 Scanning electron microscope image at point A in the figure. Fig. 11B yes Fig.11A Magnified view of area D in FIG. Fig. 12A Look up Fig.10 Scanning electron microscope image at point B in the figure. Fig. 12B yes Fig. 12A Magnified view of area E in FIG.

[0038] Figure 13-Figure 17 According to one embodiment of the present application, Fig.10 Schematic diagrams at various steps of the bonding structure shown.

[0039] Fig.18 is a scanning electron microscope image when the first conductive connection protrusion is a first dendrite connection structure. DETAILED DESCRIPTION

[0040] The following will be combined with the drawings in the embodiments of the present application to clearly and completely describe the technical solutions in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. All other embodiments obtained by ordinary technicians in this field based on the embodiments in the present application belong to the scope of protection of this application.

[0041] The following disclosure provides many different embodiments or examples for realizing different features of the provided subject matter. Specific examples of components and arrangements will be described below to simplify the present invention. Of course, these are merely examples and are not intended to limit the present invention. For example, in the following description, forming a first component above or on a second component may include an embodiment in which the first component and the second component are in direct contact, and may also include an embodiment in which an additional component is formed between the first component and the second component so that the first component and the second component may not be in direct contact. Moreover, the present invention may repeatedly refer to numbers and / or letters in various examples. This repetition is only for simplicity and clarity, and does not itself represent the relationship between the various embodiments and / or configurations discussed.

[0042] In addition, the embodiments in the present application and the features in the embodiments may be combined with each other in the absence of conflicts. The present application will be described in detail below with reference to the accompanying drawings and in conjunction with the embodiments. It should be understood that the specific structures shown in the drawings are only for the sake of convenience of explanation and are not intended to limit the present application. When describing a specific figure, other structures not described in the drawings may be provided according to actual needs and are not intended to limit the present application.

[0043] Figure 3 is a schematic cross-sectional view of a bonding structure 30 according to an embodiment of the present application. Figure 3 As shown, the bonding structure 30 of the present application may include a first electrical connector 31, a first conductive connection protrusion 41 and a first polymer layer 51, the first conductive connection protrusion 41 protrudes from the connection surface 311 of the first electrical connector 31, the first conductive connection protrusion 41 has a first strip-shaped branch 411 embedded in the first polymer layer 51, and the first polymer layer 51 surrounds the peripheral side of the first electrical connector 31 and laterally covers the first conductive connection protrusion 41. Although the first conductive connection protrusion 41 shown in the figure is a dendrite-shaped structure, it should be understood that the first conductive connection protrusion 41 can have any suitable shape according to requirements, as long as the first conductive connection protrusion 41 protrudes from the connection surface 311 of the first electrical connector 31 and has a first strip-shaped branch 411 embedded in the first polymer layer 51. The first conductive connection protrusion 41 in the bonding structure 30 of the present application has a first strip branch 411 embedded in the first polymer layer 51, which can increase the bonding area between the first conductive connection protrusion 41 and the first polymer layer 51, so as to increase the bonding strength between the first conductive connection protrusion 41 and the first polymer layer 51, thereby contributing to enhancing the bonding strength of the bonding structure 30, so as to improve the reliability of the bonding structure 30.

[0044] In some embodiments, the bonding structure 30 may further include a third electrical connector 33 electrically connected to the first electrical connector 31, and the third electrical connector 33 and the first conductive connection protrusion 41 are located on opposite sides of the first electrical connector 31. It should be understood that the third electrical connector 33 may be provided or not provided according to actual needs. In an embodiment including the third electrical connector 33, the first polymer layer 51 in the bonding structure 30 may further surround the peripheral side of the third electrical connector 33. In some embodiments, the third electrical connector 33 may be a copper column.

[0045] In some embodiments, the first conductive connection protrusion 41 is a first dendrite connection structure composed of multiple dendrites grown on the connection surface 311 of the first electrical connection member 31, and the first dendrite connection structure has a first dendrite 21 in contact with the first polymer layer 51, and the first dendrite 21 includes a first body 211 connected to the first electrical connection member 31 and a first branch 212 branched from the first body 211 and embedded in the first polymer layer 51, and the first branch 212 constitutes a first strip branch 411. Figure 3As shown, the first dendrite connection structure has a plurality of main branches (main bodies) growing from the connection surface 311 of the first electrical connector 31 and electrically connected to the first electrical connector 31, and branches branching out from each of the plurality of main branches, wherein one main branch and the branches thereon constitute a dendrite, and in one embodiment, the main branch of each dendrite is perpendicular to the connection surface 311 of the first electrical connector 31, and the angle between the branch and the main branch is 60°. In other embodiments, any suitable angle may be present between the main branch of the dendrite and the connection surface 311 of the first electrical connector 31 or between the branch and the main branch.

[0046] The first conductive connection protrusion 41 in the bonding structure 30 in the embodiment of the present application is a first dendrite connection structure composed of multiple dendrites, wherein the branches in the first dendrite connection structure can fill the gaps, thereby improving the porosity of the bonding structure 30 during bonding, reducing the proportion of pores, and increasing the metal filling rate in the bonding structure (when the material of the conductive connection protrusion is copper, the copper content is increased). In addition, the first conductive connection protrusion 41 in the bonding structure 30 in the embodiment of the present application is a first dendrite connection structure composed of multiple dendrites, so that the bonding structure 30 can be bonded in a short time under relatively low temperature and low pressure environmental conditions, reducing costs and avoiding damage to other structures (not shown) in the bonding structure.

[0047] In some embodiments, the first dendrite 21 may further include a third branch 213 branching from the first branch 212, and the third branch 213 is also embedded in the first polymer layer 51. Obviously, it can be understood that the first electrical connector 31, the first conductive connection protrusion 41, and the branches branching from the first conductive connection protrusion 41 in the embodiments of the present application are all electrically conductive / thermally conductive.

[0048] In some embodiments, there is a gap 60 between the first body 211 and the first polymer layer 51 , and the vertical projection of the first branch 212 onto the first body 211 overlaps with the vertical projection of the gap 60 onto the first body 211 . In other words, the gap 60 overlaps with the first branch 212 horizontally.

[0049] In some embodiments, the first body 211 and the first branch 212 are both cylindrical, and the diameter of the first body 211 is larger than the diameter of the first branch 212 .

[0050] Figure 4 FIG. 1 is a schematic cross-sectional view of a bonding structure 30 according to another embodiment of the present application. Figure 3 The difference is, Figure 4 The first conductive connection protrusion 41 in Figure 3 The first conductive connection protrusion 41 has different shapes. Figure 4 The dendrites in the first conductive connection protrusion 41 are Figure 3The dendrites in the first conductive connection protrusion 41 have different shapes. Figure 4 The first dendrite connection structure formed by multiple dendrites of the first conductive connection protrusion 41 is more compact and dense.

[0051] Figure 5 yes Figure 4 and Figure 6 An enlarged schematic diagram of area A in FIG. Figure 5 As shown, the first dendrite connection structure has a first dendrite 21 in contact with the first polymer layer 51, and the first dendrite 21 includes a first electrical connection member 31 (see Figure 4 and Figure 6 ) and a first branch 212 branched from the first body 211 and embedded in the first polymer layer 51, the first branch 212 constituting a first strip branch 411. In some embodiments, the first dendrite 21 may further include a third branch 213 branched from the first branch 212, the third branch 213 also being embedded in the first polymer layer 51. In some embodiments, there is a gap 60 between the first body 211 and the first polymer layer 51, and a vertical projection of the first branch 212 to the first body 211 overlaps with a vertical projection of the gap 60 to the first body 211.

[0052] Figure 6 is a schematic cross-sectional view of a bonding structure 30 according to another embodiment of the present application. Figure 7 yes Figure 6 Schematic diagram of the enlarged area B in the reference Figure 6 and Figure 7 As shown, the bonding structure 30 of the embodiment of the present application may also include a second conductive connection protrusion 42 and a second electrical connector 32 arranged above and below the first electrical connector 31, wherein the second conductive connection protrusion 42 protrudes from the connection surface 321 of the second electrical connector 32, and the bonding structure 30 may also include a second polymer layer 52, the second polymer layer 52 surrounds the peripheral side surface of the second electrical connector 32 and laterally covers the second conductive connection protrusion 42, wherein the first conductive connection protrusion 41 is electrically connected face to face with the second conductive connection protrusion 42, and the second conductive connection protrusion 42 has a second strip-shaped branch 421 embedded in the second polymer layer 52. Although the first conductive connection protrusion 41 and the second conductive connection protrusion 42 shown in the figure are both dendrite connection structures composed of multiple dendrites, it should be understood that the first conductive connection protrusion 41 and the second conductive connection protrusion 42 can have any suitable shape according to requirements.

[0053] In some embodiments, the side surface 312 of the first electrical connector 31 and the side surface 322 of the second electrical connector 32 are staggered or aligned vertically.

[0054] In some embodiments, the first electrical connection member 31 and the second electrical connection member 32 are both pads.

[0055] In some embodiments, the top surface 511 of the first polymer layer 51 and the connection surface 311 of the first electrical connector 31 are located on the same side of the first electrical connector 31, the top surface 521 of the second polymer layer 52 and the connection surface 321 of the second electrical connector 32 are located on the same side of the second electrical connector 32, and the top surface 511 of the first polymer layer 51 and the top surface 521 of the second polymer layer 52 are directly bonded together. In the bonding structure 30 of the embodiment of the present application, the first conductive connection protrusion 41 and the second conductive connection protrusion 42 are electrically connected face to face, and the top surface 511 of the first polymer layer 51 and the top surface 521 of the second polymer layer 52 are directly bonded together to form a hybrid bond, and the first conductive connection protrusion 41 has a first strip-shaped branch 411 (see Figure 5 ), and the second conductive connection protrusion 42 has a second strip-shaped branch 421 embedded in the second polymer layer 52 (see Figure 7 ), which can greatly improve the reliability of the bonding structure 30.

[0056] In some embodiments, the second conductive connection protrusion 42 is a second dendrite connection structure composed of multiple dendrites grown on the connection surface 321 of the second electrical connector 32. The second dendrite connection structure has a second dendrite 22 in contact with the second polymer layer 52. The second dendrite 22 includes a second main body 221 connected to the second electrical connector 32 and a second branch 222 branched from the second main body 221 and embedded in the second polymer layer 52. The second branch 222 constitutes a second strip branch 421.

[0057] Figure 8 yes Figure 6 Schematic diagram of the enlarged area C in the reference Figure 6 , Figure 5 and Figure 8 As shown, the first conductive connection protrusion 41 in the bonding structure 30 of the embodiment of the present application is a first dendrite connection structure formed by multiple dendrites grown on the connection surface 311 of the first electrical connector 31, the first dendrite connection structure has a first dendrite 21 in contact with the first polymer layer 51, the first dendrite 21 includes a first main body 211 connected to the first electrical connector 31 and a plurality of first branches 212 branched from the first main body 211, one of the plurality of first branches 212 is embedded in the first polymer layer 51 and another one is embedded in the second polymer layer 52 together with the second branch 222.

[0058] Although Figure 6Not shown, the second dendrite connection structure may have a portion that enters into the first polymer layer 51. In some implementations, the second dendrite connection structure may have a first sub-portion that enters into the first dendrite connection structure, and the first dendrite connection structure may have a second sub-portion that enters into the second dendrite connection structure, and the first sub-portion and the second sub-portion are in contact with each other.

[0059] The first conductive connection protrusion 41 in the joint structure 30 in the embodiment of the present application is a first dendrite connection structure formed by multiple dendrites grown on the connection surface 311 of the first electrical connector 31, and the second conductive connection protrusion 42 is a second dendrite connection structure composed of multiple dendrites grown on the connection surface 321 of the second electrical connector 32. The first conductive connection protrusion 41 is electrically connected face to face with the second conductive connection protrusion 42, wherein the branches in the first dendrite connection structure and the second dendrite connection structure can fill the gap, thereby improving the porosity during the joint, reducing the porosity ratio, increasing the metal filling rate in the joint structure, and improving the conductivity (thermal or electrical) of the connector. In addition, the advantages of lower temperature, lower pressure, and shorter time can be used for jointing.

[0060] Return to reference Figure 3 As shown, according to another embodiment of the present application, the bonding structure 30 of the present application may include a first electrical connector 31, a first polymer layer 51, and a first conductive connection protrusion 41, wherein the first polymer layer 51 surrounds the peripheral side of the first electrical connector 31 and the top surface 511 of the first polymer layer 51 is higher than the connection surface 311 of the first electrical connector 31, the first conductive connection protrusion 41 protrudes from the connection surface 311 of the first electrical connector 31 and is electrically connected to the first electrical connector 31, and the first conductive connection protrusion 41 has a portion located in the space formed by the first electrical connector 31 and the first polymer layer 51, and a first strip branch 411 embedded in the first polymer layer 51. The first conductive connection protrusion 41 in the bonding structure 30 of the present application has a first strip branch 411 embedded in the first polymer layer 51, which can increase the bonding area between the first conductive connection protrusion 41 and the first polymer layer 51, so as to increase the bonding strength between the first conductive connection protrusion 41 and the first polymer layer 51, thereby contributing to enhancing the bonding strength of the bonding structure 30, so as to improve the reliability of the bonding structure 30.

[0061] In some embodiments, the first electrical connection member 31 may be a cylindrical copper pad.

[0062] In some embodiments, the highest point of the first conductive connection protrusion 41 compared to the connection surface 311 of the first electrical connection member 31 is aligned with the top surface of the first polymer layer 51. When the first conductive connection protrusion 41 is a first dendrite connection structure, the heights of the main bodies of the plurality of dendrites may be different from each other, wherein the vertex of the main body of the highest dendrite is the highest point of the first conductive connection protrusion 41 compared to the connection surface 311 of the first electrical connection member 31.

[0063] In some embodiments, the first polymer layer 51 may be a polyimide layer.

[0064] Fig. 9 FIG. 4 is a schematic cross-sectional view of a bonding structure 90 not including a first polymer layer according to an embodiment of the present application. Fig.10 yes Fig. 9 The illustrated schematic diagram shows a state where the bonding structure 90 is rotated 90° clockwise and then wrapped with a fixing tape (eg, polyimide tape). Fig.11A It is overlooking Fig.10 Scanning electron microscope image at point A in the figure. Fig. 11B yes Fig.11A Magnified view of area D in FIG. Fig. 12A Look up Fig.10 Scanning electron microscope image at point B in the figure. Fig. 12B yes Fig. 12A Magnified view of area E in FIG.

[0065] refer to Fig. 9 As shown, the first electrical connector 31 and the second electrical connector 32 arranged above and below the first electrical connector 31 are electrically connected face to face with the second conductive connection protrusion 42 through the first conductive connection protrusion 41, wherein the first conductive connection protrusion 41 is a first dendrite connection structure formed by multiple dendrites grown on the connection surface 311 of the first electrical connector 31, and the second conductive connection protrusion 42 is a second dendrite connection structure composed of multiple dendrites grown on the connection surface 321 of the second electrical connector 32, and the materials of the first dendrite connection structure and the second dendrite connection structure are both copper. Fig.11A The first electrical connector 31, the second electrical connector 32, and the first conductive connection protrusion 41 and the second conductive connection protrusion 42 joined together are shown. Fig.11A It can be seen that the copper filling rate of the bonding structure 90 at point A is as high as 60%. Fig. 12A The first electrical connector 31, the second electrical connector 32, and the first conductive connection protrusion 41 and the second conductive connection protrusion 42 joined together are shown. Fig. 12AIt can be obtained that the copper filling rate of the bonding structure 90 at point B is as high as 50%. The copper filling rates of 50% and 60% are measured when the first electrical connector 31 and the second electrical connector 32 are both 0.5 cm*4 cm copper pads. If the sizes of the first electrical connector 31 and the second electrical connector 32 are in the nanometer range, the copper filling rate will be further improved.

[0066] Figure 13-Figure 17 According to one embodiment of the present application, Fig.10 Schematic diagrams of the bonding structure 90 at various steps are shown.

[0067] refer to Fig.13 As shown, a first conductive connection protrusion 41 is formed by electroplating on the first electrical connection member 31 through an electroplating process, and the first conductive connection protrusion 41 is a first dendrite connection structure formed by a plurality of dendrites grown on the connection surface 311 of the first electrical connection member 31. The first electrical connection member 31 may be a copper pad, and by adjusting the electroplating parameters, a dendrite structure may be directly drawn on the copper pad, that is, a first dendrite connection structure is formed.

[0068] refer to Fig.14 As shown, a schematic top view of the first electrical connector 31 and the first conductive connection protrusion 41 is shown, which can be placed in a suitable container, such as a culture dish, and the oxide layer on the surface of the first conductive connection protrusion 41 is removed by citric acid.

[0069] refer to Fig.15 As shown, a first electrical connector 31 and a first conductive connection protrusion 41, as well as a second electrical connector 32 and a second conductive connection protrusion 42 are provided, wherein the second electrical connector 32 and the second conductive connection protrusion 42 are also provided through Fig.13 , Fig.14 The first electrical connection member 31 and the second electrical connection member 32 are arranged up and down, and the first conductive connection protrusion 41 and the second conductive connection protrusion 42 face to face.

[0070] refer to Fig.16 As shown in FIG. 1 , after the bonding process steps of 0.3 MPa pressure and less than 200° C., the first electrical connector 31 and the second electrical connector 32 are electrically connected face to face through the first conductive connection protrusion 41 and the second conductive connection protrusion 42 to form a bonding structure 90. The bonding structure 90 is rotated 90° clockwise as shown in FIG. Fig.17 As shown, the fixing strap is omitted.

[0071] Fig.17 , the grinding and polishing process stops at the line AA′, and then the copper filling rate at point B of the bonding structure 90 is observed from bottom to top.

[0072] Fig.18 3 is a scanning electron microscope image when the first conductive connection protrusion 41 is a first dendrite connection structure, showing the appearance of the first dendrite connection structure.

[0073] The dendrite connection structure in the embodiment of the present application can grow quickly above the electrical connector (for example, a copper pad), making the hybrid bonding more cost-effective. In addition, the advantages of lower temperature, low pressure, and short time can be used for bonding, which is better than the cost and time required for nanowire bonding. By filling the pores during bonding with the dendrite connection structure, the metal filling rate in the bonding structure can be increased and the proportion of pores can be reduced. The bonding structure of the embodiment of the present application applies the dendrite connection structure to copper-to-copper hybrid bonding, which can effectively help integrate the packaging process of 2.5D / 3D chip stacking, the inherent advantages of multi-dimensional space and multi-chip interconnection, and the advantage of being able to increase heat dissipation capacity without increasing costs too much.

[0074] The above description is only a preferred embodiment of the present application and is not intended to limit the present application. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present application should be included in the protection scope of the present application.

Claims

1. A joining structure, characterized in that: include: a first electrical connector; A first conductive connection protrusion and a first polymer layer, wherein the first conductive connection protrusion protrudes from a connection surface of the first electrical connector, the first conductive connection protrusion has a first strip branch embedded in the first polymer layer, and the first polymer layer surrounds the peripheral side surface of the first electrical connector and laterally covers the first conductive connection protrusion.

2. The joining structure according to claim 1, characterized in that: The first conductive connection protrusion is a first dendrite connection structure composed of multiple dendrites grown on the connection surface of the first electrical connector, the first dendrite connection structure has a first dendrite in contact with the first polymer layer, the first dendrite includes a first main body connected to the first electrical connector and a first branch branched from the first main body and embedded in the first polymer layer, the first branch constitutes the first strip branch.

3. The joining structure according to claim 2, characterized in that: The first dendrite further includes a third branch branching from the first branch, and the third branch is embedded in the first polymer layer.

4. The joining structure according to claim 2, characterized in that: There is a gap between the first main body and the first polymer layer, and a vertical projection of the first branch onto the first main body overlaps with a vertical projection of the gap onto the first main body.

5. The joining structure according to claim 1, characterized in that: Also includes: A second conductive connection protrusion and a second electrical connection member arranged above and below the first electrical connection member, wherein the second conductive connection protrusion protrudes from a connection surface of the second electrical connection member; a second polymer layer, the second polymer layer surrounds the peripheral side of the second electrical connection member and laterally covers the second conductive connection protrusion, The first conductive connection protrusion is electrically connected to the second conductive connection protrusion face to face, and the second conductive connection protrusion has a second strip-shaped branch embedded in the second polymer layer.

6. The joining structure according to claim 5, characterized in that: The second conductive connection protrusion is a second dendrite connection structure composed of multiple dendrites grown on the connection surface of the second electrical connector, the second dendrite connection structure has a second dendrite in contact with the second polymer layer, the second dendrite includes a second main body connected to the second electrical connector and a second branch branched from the second main body and embedded in the second polymer layer, the second branch constitutes the second strip branch.

7. The joining structure according to claim 6, characterized in that: The first conductive connection protrusion is a first dendrite connection structure formed by multiple dendrites grown on the connection surface of the first electrical connector, the first dendrite connection structure has a first dendrite in contact with the first polymer layer, the first dendrite includes a first main body connected to the first electrical connector and multiple first branches branching from the first main body, one of the multiple first branches is embedded in the first polymer layer and another one is embedded in the second polymer layer together with the second branch.

8. The joining structure according to claim 7, characterized in that: The second dendrite connecting structure has a first sub-portion entering into the first dendrite connecting structure, the first dendrite connecting structure has a second sub-portion entering into the second dendrite connecting structure, and the first sub-portion and the second sub-portion are in contact with each other.

9. A joining structure, characterized in that: include: a first electrical connector; A first polymer layer surrounds the peripheral side of the first electrical connector, and a top surface of the first polymer layer is higher than a connection surface of the first electrical connector; The first conductive connection protrusion protrudes from the connection surface of the first electrical connector and is electrically connected to the first electrical connector. The first conductive connection protrusion has a portion located in the space formed by the first electrical connector and the first polymer layer, and a first strip branch embedded in the first polymer layer.

10. The joining structure according to claim 9, characterized in that: The highest point of the first conductive connection protrusion compared to the connection surface of the first electrical connection member is aligned with the top surface of the first polymer layer.

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