Joint structure

Abstract

Some embodiments of the present application provide a bonding structure comprising: a first bump comprising a first upper surface, the first upper surface comprising a first region and a second region lower than the first region; a first line over the first region; and a second line over the second region, where a length of the first line is less than a length of the second line. The bonding structure provided by the utility model can have a more stable structure and better electrical performance.

Description

Technical Field

[0001] An embodiment of the present application relates to a bonding structure. Background Art

[0002] The formation of the nanowires includes etching the metal layer to etch a plurality of nanowires from the metal layer. Figures 1A to 1C As shown, in Figure 1A In the embodiment, a pad 12 is provided on a substrate 13, and a metal layer 11 is provided on the pad 12. In the process of etching the metal layer 11 to etch a plurality of nanowires 15 (wherein the residual nanowire bottom 15' is shown), since etching chemicals (liquid and gas) 14 are provided from top to bottom during etching, when the etching chemicals 14 simultaneously contact the same horizontal upper surface area of ​​the metal layer 11, the etching contacting the central area C' of the metal layer 11 will flow toward the edge area P', as shown in path D. In addition, the etching chemicals 14 above the edge area P' cause the nanowires 15 in the central area C' of the upper surface of the etched metal layer 11 to be longer and the edge area P' to be shorter, thereby causing the subsequent connection with the nanowire 16 on another pad 17 (provided on a substrate 18) (wherein the residual nanowire bottom 16' is shown) to form a bonding structure 10 to fail to be electrically connected to another pad 17 or nanowire 16 on the opposite side, see Figure 1C In the regions A and A′, the electrical properties of the bonding structure 10 are reduced.

[0003] In summary, in the existing bonding structure 10, in the bonding of the nanowire 15 and the nanowire 16 from the pad 17 to the pad 12, a connection mismatch problem may always occur in the edge area P' of the pads 17 and 12 during the manufacturing process due to the short nanowires 15 and 16, that is, the connection cannot be made. Therefore, due to the small contact area, the electrical performance of the bonding structure 10 is poor or fails.

[0004] These problems are due to the fact that a large amount of chemical substances 14 are generated during the electroplating and etching processes. In addition, at the edge regions P' of the pads 17 and 12, the nanowires 15 and 16 are scattered, and since there is no structural boundary, connection mismatch problems occur. Therefore, there is an urgent need to provide a bonding structure 10 with better electrical performance. Utility Model Content

[0005] In order to solve the above problems, the present application solves the connection mismatch problem of the corresponding nanowires in the edge area by controlling the length of the nanowires set on the bumps in the central area and edge area of ​​the corresponding bumps.

[0006] An embodiment of the present application provides a bonding structure, including: a first bump, including a first upper surface, the first upper surface including a first area and a second area lower than the first area; a first line, located above the first area; and a second line, located above the second area, wherein the length of the first line is less than the length of the second line.

[0007] In some embodiments, the first line includes a first end away from the first region, and the second line includes a second end away from the second region, wherein the first end and the second end are at a first level.

[0008] In some embodiments, an extending direction of the first line is different from an extending direction of the second line.

[0009] In some embodiments, the bonding structure also includes: a second protrusion, including a second lower surface facing the first upper surface, the second lower surface including a third area and a fourth area higher than the third area; a third line located below the third area; and a fourth line located below the fourth area, wherein the length of the third line is less than the length of the fourth line.

[0010] In some embodiments, the third line includes a third end away from the third region, and the fourth line includes a fourth end away from the fourth region, wherein the third end and the fourth end are at a second level.

[0011] In some embodiments, an extending direction of the third line is different from an extending direction of the fourth line.

[0012] In some embodiments, the first line contacts the third line, and the second line contacts the fourth line.

[0013] In some embodiments, a contact angle between the first line and the third line is greater than a contact angle between the second line and the fourth line.

[0014] In some embodiments, the first bump and the second bump have the same or different shapes.

[0015] In some embodiments, the bonding structure further includes: a first carrier disposed below the first bump; a first pad disposed on a back surface of the first carrier away from the first bump, wherein the first bump extends from above the first carrier through the first carrier to the first pad.

[0016] In some embodiments, in a top view, a portion of the first bump disposed above the first carrier has a square, circular, polygonal, irregular and / or strip shape.

[0017] In some embodiments, a maximum height of a portion of the first bump disposed over the first carrier is smaller than a height of a portion of the first bump disposed in the dielectric layer.

[0018] In some embodiments, a maximum height of a portion of the first bump disposed above the first carrier is greater than a height of a portion of the first bump disposed in the dielectric layer, wherein the portion of the first bump disposed above the first carrier is a pillar structure.

[0019] In some embodiments, a maximum height of a portion of the first bump disposed above the first carrier is greater than a height of a portion of the first bump disposed in the dielectric layer, wherein the portion of the first bump disposed above the first carrier is a stepped structure.

[0020] In some embodiments, the stepped structure has a first portion and a second portion located above the first portion, wherein in a top view, a footprint of the second portion is smaller than a footprint of the first portion.

[0021] In some embodiments, the joining structure also includes: a first carrier disposed below the first bump; a first solder pad embedded in the first carrier, wherein a top surface of the first solder pad is exposed from a front side surface of the first carrier adjacent to the first bump, wherein the first bump is disposed above the first solder pad, and wherein the first solder pad extends beyond a lateral extent of the first bump.

[0022] In some embodiments, the joining structure also includes: a first carrier disposed below the first bump; a first solder pad disposed above a front side surface of the first carrier close to the first bump, wherein the first bump is disposed above the first solder pad, and wherein the first solder pad extends beyond a lateral range of the first bump.

[0023] An embodiment of the present application also provides a bonding structure, comprising: a first bump, comprising a first upper surface, the first upper surface comprising a first area and a second area surrounding the first area; a first line, located above the first area; and a second line, located above the second area, wherein a first end of the first line away from the first area and a second end of the second line away from the second area are at the same level.

[0024] In some embodiments, the first region is higher than the second region, and a length of the first line is less than a length of the second line.

[0025] In some embodiments, an extending direction of the first line is different from an extending direction of the second line.

[0026] The bonding structure provided by the present application may have a more stable structure and better electrical performance. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] When read in conjunction with the accompanying drawings, various aspects of the present invention can be best understood from the following detailed description. It should be noted that, in accordance with standard practice in the industry, the various components are not drawn to scale. In fact, for the sake of clarity of discussion, the size of the various components can be arbitrarily increased or reduced.

[0028] Figures 1A to 1C A prior art bonding structure is shown.

[0029] FIG. 2A to FIG. 2F A bonding structure according to some embodiments of the present application is shown.

[0030] Figure 3 , FIG. 3A to FIG. 3E A top view of a portion of the bonding structure of the present application is shown.

[0031] Figure 3G to Figure 3F A carrier of the bonding structure of the present application is shown.

[0032] Figures 4 to 25 The process flow of manufacturing a bonding structure according to some embodiments of the present application is shown. DETAILED DESCRIPTION

[0033] The following disclosure provides many different embodiments or examples for realizing different features of the present invention. Specific examples of components and arrangements are described below to simplify the present invention. Of course, these are merely examples and are not intended to limit the present invention. In addition, when "approximately", "about", "substantially", etc. are used to describe a numerical value or a numerical range, unless otherwise specified, the term is intended to cover a numerical value within ±10% of the described numerical value. For example, the term "about 5nm" covers a size range from 4.5nm to 5.5nm.

[0034] The bonding structure provided by the embodiment of the present application can solve the connection mismatch problem of the corresponding nanowires in the edge area by controlling the length of the nanowires set on the bumps in the central area and the edge area of ​​the corresponding bumps.

[0035] See also Figure 2A Some embodiments of the present application provide a bonding structure 100, the bonding structure 100 includes a first bump 101, the first bump 101 includes a first upper surface 101s, the first upper surface 101s includes a first region C1 and a second region P1 lower than the first region C1. In some embodiments, the first region C1 is a central region, and the second region P1 is an edge region. In an embodiment, the bonding structure 100 also includes a first line 105A located above the first region C1 and a second line 105B located above the second region P1, from Figure 2A It can be seen that the length of the first line 105A is less than the length of the second line 105B. Figure 2A As shown, the first line 105A includes a first end 105Ae away from the first region C1 of the first upper surface 101s of the first bump 101, and the second line 105b includes a second end 105Be away from the second region P1, and Figure 2A As can be seen in FIG. 1 , the first end 105Ae and the second end 105Be are at the first level L1. It is worth noting that the length of the first line 105A and the length of the second line 105B are measured from the bottom 105' of the corresponding first line 105A and the second line 105B to the first end 105Ae of the first line 105A or the second end 105Be of the second line 105B. Further, Figure 2A The lower right corner of FIG. 1 shows an extension direction D1 of a portion of the first line 105A, and shows an extension direction D2 of a portion of the second line 105B. It can be seen that the extension direction D1 of the first line 105A is different from the extension direction D2 of the second line 105B.

[0036] In addition, the bonding structure 100 further includes a second bump 107. Similarly, the second bump 107 includes a second lower surface 107s facing the first upper surface 101s. The second lower surface 107s includes a third region C2 and a fourth region P2 higher than the third region C2. In some embodiments, the third region C2 is a central region, and the fourth region P2 is an edge region. In an embodiment, the bonding structure 100 further includes a third line 106A located below the third region C2 and a fourth line 106B located below the fourth region P2. Figure 2A It can be seen from FIG. 1 that the length of the third line 106A is less than the length of the fourth line 106B. Similarly, the third line 106A includes a third end 106Ae away from the third region C2, and the fourth line 106B includes a fourth end 106Be away from the fourth region P2. Figure 2A As can be seen from the figure, the third end 106Ae and the fourth end 106Be are at the second level L2. In some embodiments, the first line 105A contacts the third line 106A, and the second line 105B contacts the fourth line 106B. Figure 2A As can be seen from the bonding structure 100 shown, the first line 105A and the third line 106A and the second line 105B and the fourth line 106B are cross-linked and bonded, so the first level L1 and the second level L2 are different and are at different levels. Figure 2AThe upper right corner of FIG. 1 shows the extension direction D3 of some of the third wires 106A, and shows the extension direction D4 of some of the fourth wires 106B. It can be seen that the extension direction D3 of the third wire 106A is different from the extension direction D4 of the fourth wire 106B. In some embodiments, the first wire 105A, the second wire 105B, the third wire 106A, and the fourth wire 106B may be nanowires.

[0037] exist Figure 2A In the illustrated bonding structure 100, the contact angle between the first wire 105A and the third wire 106A is greater than the contact angle between the second wire 105B and the fourth wire 106B. Figure 2B , Figure 2B Shows Figure 2A A magnified view of area A. Figure 2B As shown, the second line 105B and the fourth line 106B both generate a certain cohesive force. Further, the second line 105B has a cohesive force Pb, which can also be called a bottom tension, and the fourth line 106B has a cohesive force Pt, which can also be called a top tension. In some embodiments, the cohesive force Pb of the second line 105B in the transverse direction x, the bonding force Pbx, and the bonding force Ptx of the cohesive force Pt of the fourth line 106B in the transverse direction x make them compact and high density (not easy to be dispersed), and the bonding force Pby of the cohesive force Pb of the second line 105B in the vertical direction y and the bonding force Pty of the cohesive force Pt of the fourth line 106B in the vertical direction y make the second line 105B and the fourth line 106B have a higher contact density, that is, when Pb, Pbx and Pby and Pt, Ptx and Pty meet the following conditions, it is most conducive to the bonding of the second line 105B and the fourth line 106B:

[0038]

[0039]

[0040] Total tensile force ∑F in the transverse direction x x and the total tension in the vertical direction∑F y The following conditions must be met:

[0041]

[0042]

[0043] It can be seen that when the cohesive force Pb (ie, bottom tension) of the second wire 105B and the cohesive force Pt (ie, top tension) of the fourth wire 106B meet the above conditions, the second wire 105B and the fourth wire 106B can be well bonded.

[0044] Next, see Figure 2AThe bonding structure 100 further includes: a first carrier 103 disposed below the first bump 101, a first pad 102 disposed between the first bump 101 and the first carrier 103 and disposed above a front side surface 103f of the first carrier 103 close to the first bump 101, wherein the first bump 101 is disposed above the first pad 102 and a seed layer 110 is further disposed between the first pad 102 and the first bump 101. Figure 2A In the cross-sectional view shown, the first pad 102 extends beyond the lateral extent of the first bump 101, that is, the width of the first pad 102 in the lateral direction x is greater than the maximum width of the first bump 101 in the lateral direction x. Similarly, the bonding structure 100 further includes: a second carrier 104 disposed above the second bump 107, a second pad 108 disposed between the second bump 107 and the second carrier 104 and disposed above a front side surface 104f of the second carrier 104 close to the second bump 107, wherein the second bump 107 is disposed below the second pad 108 and a seed layer 111 is further disposed between the second pad 108 and the second bump 107. Figure 2A In the cross-sectional view shown in FIG. 1 , the second pad 108 extends beyond the lateral extent of the second bump 107, that is, the width of the second pad 108 in the lateral direction x is greater than the maximum width of the second bump 107 in the lateral direction x. In some other embodiments, the bonding structure 100 further includes a protective layer 109 that seals the first bump 101 and the second bump 107, such as Figure 2A shown.

[0045] It can be seen that in the above Figure 2A In the embodiment shown, the first bump 101 and the second bump 107 have the same shape, and are not both semicircular. In other embodiments, the first bump 101 and the second bump 107 have different shapes, as described in detail below.

[0046] Next, see Figure 2C , Figure 2C The illustrated engagement structure 200 is Figure 2A The joint structure 100 shown is similar, except that Figure 2C In the illustrated bonding structure 200, the first pad 102 is disposed at the backside surface 103b of the first carrier 103 away from the first bump 101, and the first bump 101 extends from above the first carrier 103 through the first carrier 103 to the first pad 102. In this embodiment, the seed layer 110 is still disposed between the first pad 102 and the first bump 101. In addition, the shape of the second bump 107 is different from that of the first bump 101, but in some embodiments, the shape of the second bump 107 can also be the same as that of the first bump 101, such as the shape of the second bump 107 can be changed to Figure 2CThe shape of the first bump 101 is shown in FIG. Figure 2C In the illustrated first bump 101 , a maximum height h1 of a portion of the first bump 101 disposed above the first carrier 103 is smaller than a height h2 of a portion of the first bump 101 disposed in the dielectric layer 103 .

[0047] Figure 2D A bonding structure 300 according to some embodiments is shown. Figure 2A The joint structure 100 shown is similar, except that Figure 2D In the bonding structure 300 , the first pad 102 is embedded in the first carrier 103 , and the top surface of the first pad 102 is exposed from the front side surface 103 f of the first carrier 103 close to the first bump 101 , that is, the first pad 102 is embedded at the front side surface 103 f of the first carrier 103 .

[0048] Figure 2E and Figure 2F The bonding structures 400 and 500 according to other embodiments are shown respectively. For the convenience of description, only some of the reference numerals are shown. The reference numerals not shown are referred to in Figure 2A Specifically, the joint structures 400 and 500 are Figure 2A The joint structure 100 shown is similar, except that Figure 2E As shown in the bonding structures 400 and 500, the first pad 102 is disposed on the back side surface 103b of the first carrier 103 away from the first bump 101, and the first bump 101 extends from above the first carrier 103 through the first carrier 103 to the first pad 102. In addition, more importantly, in Figure 2E and Figure 2F , the maximum height h1 of the portion of the first bump 101 disposed above the first carrier 103 is greater than the height h2 of the portion of the first bump 101 disposed in the dielectric layer 103 (which is further related to Figure 2C The structure shown is different). Figure 2E In the bonding structure 400 shown in FIG. 1 , the portion of the first bump 101 disposed above the first carrier 103 is a column structure. Figure 2E The cross-sectional view shown has straight side walls, and in some other embodiments, it may also have inclined side walls. Figure 2E In the embodiment shown, the second bump 107 may also have a column structure similar to that of the first bump 101. Figure 2FIn the illustrated bonding structure 500, the portion of the first bump 101 disposed above the first carrier 103 is a stepped structure, and the stepped structure has a first portion 101A and a second portion 101B located above the first portion 101A. In a top view, the footprint of the second portion 101B is smaller than the footprint of the first portion 101A. Figure 2F In the cross-sectional view shown in FIG. 1 , the width of the second portion 101B in the transverse direction x is smaller than the width of the first portion 101A in the transverse direction x. Figure 2F The cross-sectional view shown has straight side walls, and in some other embodiments, it may also have inclined side walls. Figure 2F In the illustrated embodiment, the second bump 107 may also have a stepped structure similar to that of the first bump 101, i.e., a first portion 107A and a second portion 107B located below the first portion 107A, and the width of the second portion 107B in the lateral direction x is smaller than the width of the first portion 107A in the lateral direction x.

[0049] Next, see Figures 3 to 3E , Figure 3 Shows Figure 2C The partial structure of the bonding structure 200 is shown, and FIG. 3A to FIG. 3E FIG. 1 shows a top view of the first line 105A and the second line 105B, the first pad 102 and the first carrier 103 in the partial structure. FIG. 3A to FIG. 3F In the figure, for the convenience of explanation, the first line 105A and the second line 105B are collectively labeled as reference numeral 105. In addition, since the shapes of the first line 105A and the second line 105B in the top view are determined by the first bump 101, the top view shapes of the first line 105A and the second line 105B overlap with the top view shapes of the first bump 101, specifically, overlap with the portion of the first bump 101 disposed above the first carrier 103. Figure 3A As can be seen from the figure, the first line 105A and the second line 105B (ie, reference numeral 105) and the first bump 101 may have the following features in a top view. Figure 3A The square shown, Figure 3B The circle shown, Figure 3C The pentagonal polygon shown, Figure 3D Irregular shapes and / or Figure 3E The rectangular strip shape shown. In addition, from FIG. 3A to FIG. 3EAs can be seen in FIG. 1 , the footprint of the first pad 102 is larger than the footprint of the first bump 101 and the first and second lines 105A and 105B (i.e., reference numeral 105), and may have the same shape as the footprint of the first bump 101 and the first and second lines 105A and 105B (i.e., reference numeral 105), but may have different shapes in other embodiments. Note that since the first pad 102 is buried in the first carrier 103, FIG. 3A to FIG. 3E The top view of FIG. 1 is shown with a dotted line to indicate that the first pad 102 is not visible. In addition, Figure 3G to Figure 3F Different shapes of the first carrier 103 or the second carrier 104 are shown, that is, FIG. 2A to FIG. 2F In the illustrated bonding structures 100 - 500 , different carriers may be used, such as square or circular carriers.

[0050] Return to see Figure 2A Some other embodiments of the present application further provide a bonding structure 100, the bonding structure 100 comprising: a first bump 101, the first bump 101 comprising a first upper surface 101s, and the first upper surface 101s comprising a first region C1 and a second region P1 surrounding the first region C1. The bonding structure 100 also comprises a first line 105A located above the first region C1 and a second line 105B located above the second region P1, and a first end 105Ae of the first line 105A away from the first region C1 and a second end 105Be of the second line 105B away from the second region P1 are at the same level L1. Further, in the case of Figure 2A In the cross-sectional view shown, the first area C1 is higher than the second area P1, and the length of the first line 105A is less than the length of the second line 105B. In addition, in some embodiments, the extension direction D1 of the first line 105A is different from the extension direction D2 of the second line 105B. It should be noted that the extension directions D1 and D2 only schematically illustrate the extension directions of part of the first line 105A and part of the second line 105B.

[0051] In the above FIG. 2A to FIG. 2F In the illustrated bonding structures 100 to 500, when the bonding structure has Figure 2C In the structure of the first bump 101 shown in FIG. 1 , the portion of the first bump 101 extending through the dielectric layer 103 has a size of several micrometers (μm) in the lateral direction x, such as several hundred micrometers, and a depth of several micrometers, such as several hundred micrometers in the vertical direction y. The diameters of the first wire 105A, the second wire 105B, the third wire 106A, and the fourth wire 106B or the width in the lateral direction x are several nanometers (nm), such as several hundred nanometers. When the bonding structure 200 has a structure as shown in FIG. Figure 2CIn the structure of the first bump 101 shown, the maximum width of the first bump 101 located above the dielectric layer 103 is 1.05-1.5 times the width of the portion of the first bump 101 extending through the dielectric layer 103 at the front side surface 103f of the dielectric layer 103, such as several microns, such as hundreds of microns. In addition, the angle formed by the extension direction of the outermost fourth line 106B on the second bump 107 is in the range of about 10° to about 80°. In addition, the distance between the first carrier 103 and the second carrier 104 in the vertical direction y is in the range of from 10 microns to 50 microns. In addition, the shortest distance from the first upper surface 101S of the first bump 101 to the first end 105Ae of the first line 105A and the second end 105Be of the second line 105B at the first level L1 is less than 30 microns. Similarly, the shortest distance from the second lower surface 107s of the second bump 107 to the third end 106Ae of the third line 106A and the fourth end 106Be of the fourth line 106B at the second level L2 is also less than 30 microns. Figure 2A In the illustrated bonding structure 100, the distance from the top surface of the first pad 102 close to the first bump 101 to the first level L1 in the vertical direction y is 1-20 microns. Similarly, the distance from the top surface of the second pad 108 close to the second bump 107 to the second level L2 is also 1-20 microns. Figure 2C to Figure 2F In the illustrated bonding structures 200 - 500 , the distance from the front side surface 103 f of the first carrier 103 to the first level L1 in the vertical direction y is 1-20 μm, and the distance from the top surface of the second pad 108 close to the second bump 107 to the second level L2 is also 1-20 μm.

[0052] In the above-mentioned bonding structure, the first carrier 103, the second carrier 104 and the protective layer 109 may include organic materials, including but not limited to polyimide (PI), epoxy resin, Ajinomoto enhancement film (ABF), polypropylene (pp) or / and acrylic resin, etc., and the first carrier 103 and the second carrier 104 may also include inorganic materials, including but not limited to ceramics, silicon wafers, glass, quartz and / or gallium arsenide substrates, etc. In addition, the first carrier 103 and the second carrier 104 and the protective layer 109 may also include organic photosensitive or / and non-photosensitive liquids or / and dry film materials. In addition, the seed layers 110 and 111 and the first line 105A to the fourth line 106B may include metal materials, and may include metals or metal alloys such as copper, silver, gold, etc. The first bump 101, the second bump 107, the first pad 102 and the second pad 108, etc. may also include metal materials, such as metals or metal alloys of copper, silver, gold, etc. In some embodiments, the protective layer 109 may be a molding compound.

[0053] In summary, the bonding structure 100 provided in the present application may have the following advantages:

[0054] 1) The bonding structure 100 with the first and third wires 105A and 106A and the second and fourth wires 105B and 106B having good contact provides good integrated circuit (IC) packaging performance, and FIG. 2A to FIG. 2F It can be seen that the joining of the first thread 105A and the third thread 106A as well as the second thread 105B and the fourth thread 106B is achieved by “cross-linking”;

[0055] 2) In the second area P1 which is the edge area, the second line 105B and the fourth line 106B are bent to be tightly fixed together, and in the first area C1 which is the center area, the first line 105A and the third line 106A are directly in contact with each other to have a higher density. Therefore, the first line 105A and the third line 106A and the second line 105B and the fourth line 106B are completely in contact with each other on the first bump 101 and the second bump 107 and between the top surfaces of the first pad 102 and the second pad 108;

[0056] 3) The joint structure does not require welding, which is conducive to the solution of structural thinning, and does not require welding without the risk of welding problems such as bridging, cracks, cold joints, high resistance, and the need for the same pad size due to wetting issues.

[0057] 4) Since the first line 105A and the third line 106A as well as the second line 105B and the fourth line 106B are directly bonded by metal such as copper, they can be metal-metal bonding interconnections, thereby forming a shorter path and bringing better electrical performance;

[0058] 5) The size difference between the first pad 102 and the second pad 108 is less costly (if the first bump 101 and the second bump 107 require an additional redistribution layer (RDL)); and

[0059] 6) There are more small gaps between two bonding surfaces (such as the first upper surface 101s of the first bump 101 and the second lower surface 107s of the second bump 107), forming a reinforced structure, ie, a more stable structure.

[0060] Furthermore, in the nanowire manufacturing process of the present application, when etching chemicals (such as etching gas) contact the central area of ​​the upper surface of the metal layer at the same level from top to bottom, the etching chemicals will flow to the edge area to etch the metal in the edge area, resulting in longer lines in the central area of ​​the upper surface of the metal layer after etching. The problem can be solved by lowering the level of the edge area to reduce the contact with the etching chemicals flowing from the central area to the edge area.

[0061] The following will refer to Figures 4 to 25To introduce the formation Figure 2C The process flow of the bonding structure 200 is shown.

[0062] First, see Figures 4 to 12 , Figures 4 to 12 The formation of the second bump 107 and its associated third line 106A and fourth line 106B is shown. Figure 4 , providing a second carrier 104 on which a second pad 108 is formed, and the second carrier 104 may be a silicon wafer. Figure 5 , a seed layer 111' is formed over the second carrier 104 and the second pad 108, such as by chemical vapor deposition, physical vapor deposition, etc. In some embodiments, the seed layer 111' can be a metal layer, such as a copper layer. After forming the seed layer 111', a photoresist 1001 is deposited or laminated over the seed layer 111', such as Figure 6 The photoresist 1001 is exposed and developed E1, thereby forming an opening 1001O in the photoresist 1001. Figure 7 As shown, a second bump 107 is plated in the opening 1001O. The second bump 107 is made of metal, and in this embodiment, is made of copper. The second bump 107 can be formed by electroplating or chemical plating. Figure 7 As shown, the second bump has a second lower surface 107s.

[0063] Next, see Figure 8 , a metal layer 1002 is plated on the second bump 107. The metal layer 1002 may also be formed by electroplating or chemical plating, and may include a copper layer. After forming the metal layer 1002, see Fig. 9 and Fig.10 , Fig. 9 The metal layer 1002 is etched using an etching chemical 1003 (including other or liquid etching substances) to form a third region C2 of the second lower surface 107s. Fig.10 The third wire 106A is shown and the fourth wire 106B is formed at the fourth region P2. In this embodiment, the third wire 106A and the fourth wire 106B are nanowires, and the etching chemical 1003 may include an etching gas such as oxygen or nitrogen, or an etching liquid such as hydrochloric acid or nitric acid.

[0064] Continue to see Fig.10 , the photoresist 1001 is removed by an etching process 1004, and the etching process 1003 may be an etching process using, for example, an oxygen plasma dry etching process. Fig.11 As shown, the portion of the seed layer 111' not covered by the second bump 107 is removed by an etching chemical 1005 similar to the etching chemical 1003, thereby forming Fig.12The structure shown. Fig.12 As can be seen from the structure shown, the length of the third line 106A is shorter than that of the fourth line 106B. The third line 106A includes a third end 106Ae away from the third region C2, and the fourth line 106B includes a fourth end 106Be away from the fourth region P2, and the third end 106Ae and the fourth end 106Be are at the same second level L2.

[0065] In summary, Figures 9 to 12 In the process shown in FIG. 1 , since a photoresist 1001 is formed when forming the third line 106A and the fourth line 106B, the etching chemical 1003 (see FIG. 1 ) used is Fig. 9 ) flows from the central area (corresponding to the third area C2) to the edge area (corresponding to the fourth area P2) at a slower rate, thereby reducing the contact of the etching chemical 1003 in the edge area, thereby making the length of the third line 106A in the third area C2 different from the length of the fourth line 106B in the fourth area P2, and making the third end 106Ae of the third line 106A and the fourth end 106Be of the fourth line 106B at the same second level L2.

[0066] Next, see Figures 13 to 22 , Figures 13 to 22 The formation of the first bump 101 and its associated first line 105A and second line 105B is shown. Fig.13 , providing a first carrier 103 having a first pad 102 embedded therein, in this embodiment, the first pad 102 is disposed at a back side surface 103b of the first carrier 103, and the first carrier 103 may be a silicon wafer. Fig.14 A hole is formed at the front side surface 103f of the first carrier 103 by a laser drilling process T, thereby forming Fig.15 The opening 103O is shown, and after the opening 103O is formed, a seed layer 110' is formed over the surface of the first carrier 103 and in the opening 103O. The material and formation process of the seed layer 110' are similar to those of the seed layer 111', and will not be described in detail here.

[0067] After forming the seed layer 111 ′, see Fig.16 , forming a photoresist 1006, such as by a deposition process of physical vapor deposition or a lamination process. Then, the photoresist 1006 is exposed and developed E2, so as to form an opening 1006O in the photoresist, such as Fig.17 As shown. A second bump 101 is plated in the opening 1006O formed by the photoresist, and the second bump 101 has a first upper surface 101s. Fig.18 , forming a metal layer 1007 on the second bump 101, Fig.17 and Fig.18 The process shown is similar to that described above. Figure 7 and Figure 8 The described processes are similar and will not be described in detail here.

[0068] Next, see Fig.19 and Fig. 20 , the metal layer 1007 is etched by etching chemical 1008, thereby forming a first line 105A in the first area C1 of the first upper surface 101s and forming a second line 105B in the second area P1. Fig.21 and Fig. 22 , the portions of the photoresist 1006 and the seed layer 110' not covered by the first bump 101 are removed by etching chemicals 1009 and 1010, respectively, thereby forming Fig. 22 The structure shown. Figures 19 to 22 The process shown is similar to that shown in Figures 9 to 12 The described processes are similar and will not be described in detail here.

[0069] Figures 19 to 22 In the process shown in the figure, since a photoresist 1006 is formed when forming the first line 105A and the second line 105B, the etching chemical 1008 (see Fig.19 ) flows from the central area (corresponding to the first area C1) to the edge area (corresponding to the second area P1) at a slower rate, thereby reducing the contact of the etching chemical 1008 in the edge area, thereby making the lengths of the first line 105A in the first area C1 and the second line 105B in the second area P1 different, and making the first end 105Ae of the first line 105A and the second end 105Be of the second line 105B at the same first level L1.

[0070] Next, see Fig.23 ,Will Fig.12 The resulting structure flips and Fig. 22 The resulting structure is bonded, such as by a pick-and-place process or a press process R. Fig.24 , further through the sintering process Fig.12 The third line 106A and the fourth line 106B in the resulting structure are respectively Fig. 22 The first wire 105A and the second wire 105B of the resulting structure are bonded, such as by a sintering process above the glass transition temperature of copper. Fig.25, such as by a capillary flow process, the first bump 101 and the second bump 107 and the first wire 105A and the second wire 105B, the third wire 106A and the fourth wire 106B are sealed with a protective layer 109. In the present embodiment, the protective layer 109 uses an epoxy resin material and fills the gaps between the first wire 105A and the second wire 105B and the third wire 106A and the fourth wire 106B. Then, a Figure 2C The engagement structure 200 is shown.

[0071] In summary, in the present application, first, thicker metal layers 1002 and 1007 are respectively manufactured on the top of the first bump 101 and the second bump 107 (i.e., the first upper surface 101s and the second lower surface 107s) through two photolithography and plating processes (i.e., thereafter, the layers of the first wire 105A and the second wire 105B, the third wire 106A and the fourth wire 106B are formed respectively); thereafter, the main metal layers 1002 and 1007 are manufactured by etching and the bottoms 105' and 106' of the thin metal layers 1002 and 1007 are retained, just like manufacturing the nanowire pillars, the bottoms 105' and 106' of the thin metal layers 1002 and 1007 are retained and the first wire 105A and the second wire 105B and the third wire 106A and the fourth wire 106B are formed (see Fig. 9 and Fig.19 ).

[0072] In addition, the photoresists 1001 and 1006 and the portions of the seed layers 111 ′ and 110 ′ on the surfaces of the first carrier 103 and the second carrier 104 are removed by etching (see Figures 10 to 12 as well as Figure 20 to Figure 22 ); see Fig.24 , the bonded interconnections are formed by the first wire 105A and the second wire 105B and the third wire 106A and the fourth wire 106B on the first bump 101 and the second bump 107, respectively; finally, a protective layer 109 is used to protect the gaps between the first wire 105A and the second wire 105B and the third wire 106A and the fourth wire 106B, the first carrier 103 and the second carrier 104, and the corresponding first bump 101 and the second bump 107.

[0073] The features of several embodiments are summarized above so that those skilled in the art can better understand aspects of the present invention. Those skilled in the art should understand that they can easily use the present invention as a basis to design or modify other processes and structures for implementing the same purpose and / or achieving the same advantages as the embodiments described herein. Those skilled in the art should also appreciate that such equivalent constructions do not deviate from the spirit and scope of the present invention, and that they can make various changes, substitutions, and modifications herein without departing from the spirit and scope of the present invention.

Claims

1. A joining structure, characterized in that: include: A first bump includes a first upper surface, wherein the first upper surface includes a first area and a second area lower than the first area; a first line, located above the first zone; as well as A second line, located above the second zone, Wherein, the length of the first line is smaller than the length of the second line.

2. The joining structure according to claim 1, characterized in that: The first line includes a first end away from the first region, and the second line includes a second end away from the second region, wherein the first end and the second end are at a first level.

3. The joining structure according to claim 2, characterized in that: An extending direction of the first line is different from an extending direction of the second line.

4. The joining structure according to claim 1, characterized in that: Also includes: A second bump includes a second lower surface facing the first upper surface, the second lower surface includes a third area and a fourth area higher than the third area; a third line, located below the third zone; as well as A fourth line, located below the fourth zone, Wherein, the length of the third line is smaller than the length of the fourth line.

5. The joining structure according to claim 4, characterized in that: The third line includes a third end away from the third region, and the fourth line includes a fourth end away from the fourth region, wherein the third end and the fourth end are at a second level.

6. The joining structure according to claim 4, characterized in that: An extending direction of the third line is different from an extending direction of the fourth line.

7. The joining structure according to claim 4, characterized in that: The first line contacts the third line, and the second line contacts the fourth line.

8. The joining structure according to claim 7, characterized in that: A contact angle between the first line and the third line is greater than a contact angle between the second line and the fourth line.

9. The joining structure according to claim 1, characterized in that: Also includes: A first carrier, disposed below the first bump; A first pad is disposed on a back side surface of the first carrier away from the first bump, The first bump extends from above the first carrier through the first carrier to the first pad.

10. The joining structure according to claim 9, characterized in that: The maximum height of the portion of the first bump disposed above the first carrier is greater than the height of the portion of the first bump disposed in the dielectric layer, Wherein, a portion of the first bump disposed above the first carrier is a stepped structure.

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