Wiring board, functional backplane and method for manufacturing same

Abstract

The wiring board includes a base substrate and a plurality of first connection pads. The plurality of first connection pads are provided on the base substrate. The plurality of first connection pads include at least one electrical connection layer, and each electrical connection layer includes a body material layer and at least one protective layer. The at least one protective layer is provided on a side of the body material layer that is farther from the base substrate. The at least one protective layer includes a first reference protective layer, and the first reference protective layer is a protective layer farthest from the base substrate among the at least one protective layer, and a material of the body material layer includes copper. The at least one electrical connection layer includes a first electrical connection layer, and the first electrical connection layer is an electrical connection layer farthest from the base substrate among the at least one electrical connection layer, and in the at least one protective layer included in the first electrical connection layer, a material of at least the first reference protective layer can form a first intermetallic compound with a first solder.

Description

[Technical field]

[0001] The present disclosure relates to the lighting and display technology field, and in particular to wiring substrates, functional backplanes and methods for making the same. [Background technology]

[0002] LEDs (Light Emitting Diodes) are light-emitting devices that use inorganic semiconductor materials to form a pn junction, and when driven by an electric field, carriers combine in the pn junction to emit light, resulting in relatively high luminance and response speed. Summary of the Invention [Means for solving the problem]

[0003] In one embodiment, a wiring board is provided, the wiring board including a base substrate and a plurality of first connection pads. The plurality of first connection pads are provided on the base substrate. The plurality of first connection pads include at least one electrical connection layer, each of which includes a body material layer and at least one protective layer, and the at least one protective layer is provided on a side of the body material layer away from the base substrate. The at least one protective layer includes a first reference protective layer, the first reference protective layer being the protective layer farthest from the base substrate among the at least one protective layer, and a material of the body material layer includes copper. The at least one electrical connection layer includes a first electrical connection layer, the first electrical connection layer being the electrical connection layer farthest from the base substrate among the at least one electrical connection layer, and in the at least one protective layer included in the first electrical connection layer, at least the material of the first reference protective layer and a first solder can form a first intermetallic compound.

[0004] In some embodiments, the material of the first reference protective layer included in the first electrical connection layer is a single metal or a metal alloy.

[0005] In some embodiments, the thickness or material of the at least one protective layer included in the first electrical connection layer is configured to block diffusion of the first solder into the body material layer included in the first electrical connection layer.

[0006] In some embodiments, when the material of the first reference protective layer included in the first electrical connection layer includes copper or a copper-nickel alloy, the thickness of the first reference protective layer has a value between 300 Å and 600 Å. When the material of the first reference protective layer included in the first electrical connection layer does not include copper, the thickness of the first reference protective layer has a value between 300 Å and 30,000 Å.

[0007] In some embodiments, a diffusion depth of the first solder in the at least one protective layer is equal to or greater than a thickness of the first reference protective layer included in the first electrical connection layer.

[0008] In some embodiments, the at least one protective layer includes at least two protective layers, the at least two protective layers further including the first reference protective layer and a second reference protective layer, the second reference protective layer being located between the first reference protective layer and the base substrate, and a material of the second reference protective layer and the first solder can form a first intermetallic compound, or a material of the second reference protective layer and the first solder cannot form a first intermetallic compound.

[0009] In some embodiments, the material of the second reference protective layer and the first solder can form a first intermetallic compound, and the materials of at least two of the protective layers are different, or the thickness of at least one protective layer is greater than 500 Å, or the sum of the thicknesses of the at least two protective layers is greater than 500 Å.

[0010] In some embodiments, along a direction gradually approaching the base substrate, the diffusion depth of the first solder per unit time in the at least two protective layers gradually decreases and / or the melting point of the material of the at least two protective layers gradually increases.

[0011] In some embodiments, the percentage of elements capable of forming a first intermetallic compound with the first solder in the at least two protective layers gradually decreases along a direction gradually approaching the base substrate.

[0012] In some embodiments, the at least two protective layers have a gradually increasing thickness along a direction gradually approaching the base substrate.

[0013] In some embodiments, the diffusion depth of the first solder in the at least one protective layer is greater than or equal to the thickness of the first reference protective layer and less than or equal to the sum of the thickness of the first reference protective layer and the thickness of the second reference protective layer.

[0014] In some embodiments, the at least one electrical connection layer further includes a second electrical connection layer, the second electrical connection layer being located between the first electrical connection layer and the base substrate, and the material of the first reference protective layer included in the second electrical connection layer and the first solder can form a first intermetallic compound, or the material of the first reference protective layer included in the second electrical connection layer and the first solder cannot form a first intermetallic compound.

[0015] In some embodiments, the first reference protection layer included in the second electrical connection layer has a thickness of 300 Å or more and 30,000 Å or less.

[0016] In some embodiments, the material of the first reference protective layer included in the second electrical connection layer can form a first intermetallic compound with a first solder, and the thickness of the first reference protective layer included in the second electrical connection layer is greater than the thickness of the first reference protective layer included in the first electrical connection layer.

[0017] In some embodiments, the diffusion depth of the first solder in the at least one electrical connection layer is greater than or equal to the thickness of a first reference protective layer included in the first electrical connection layer and is less than or equal to the sum of the thickness of the first electrical connection layer and the thickness of the first reference protective layer included in the second electrical connection layer.

[0018] In some embodiments, the electronic component further comprises a plurality of second connection pads provided on the base substrate, the second connection pads configured to be electrically connected to a circuit board.

[0019] In another aspect, a functional backplane is provided, the functional backplane including the wiring substrate and first solder described above, and at least one electronic component, each electronic component including a pin, the electronic component being welded to the first connection pad via the pin and the first solder, the first solder forming a first intermetallic compound with at least the first reference protection layer included in the first electrical connection layer.

[0020] In some embodiments, the at least one electronic component includes at least one first electronic component, and in a first connection pad to be welded to a pin included in the at least one first electronic component, a groove is provided on a surface of the first reference protective layer included in the at least one first electrical connection layer that faces away from the base substrate, and a second solder is provided within the groove, and the second solder and at least a sidewall of the groove form a first intermetallic compound.

[0021] In some embodiments, the at least one electrical connection layer further includes a third electrical connection layer, the third electrical connection layer being the closest electrical connection layer to the base substrate among the at least one electrical connection layer.

[0022] The portion of the first connection pad located on one side of the bottom of the groove includes at least a portion of the first connection pad that is included in the third electrical connection layer, and the portion included in the third electrical connection layer includes at least a portion of a body material layer that is included in the third electrical connection layer.

[0023] In yet another aspect, a method for manufacturing a functional backplane is provided, the method comprising the steps of:

[0024] The method includes a step of manufacturing a wiring board, the wiring board including a base substrate and a plurality of first connection pads, the plurality of first connection pads being provided on the base substrate, the plurality of first connection pads including at least one electrical connection layer, each of the electrical connection layers including a body material layer and at least one protective layer, the at least one protective layer being provided on a side of the body material layer away from the base substrate, the at least one protective layer including a first reference protective layer, the first reference protective layer being the protective layer farthest from the base substrate among the at least one protective layer, the material of the body material layer including copper, the at least one electrical connection layer including a first electrical connection layer, the first electrical connection layer being the electrical connection layer farthest from the base substrate among the at least one electrical connection layer, and in the at least one protective layer included in the first electrical connection layer, the material of at least the first reference protective layer and a first solder can form a first intermetallic compound.

[0025] At least one electronic component is provided, with each electronic component including a pin.

[0026] The electronic component is welded to the first connection pad via the pin and the first solder, so that the first solder and at least the first reference protective layer included in the first electrical connection layer form a first intermetallic compound, and the first solder and the pin form a second intermetallic compound.

[0027] In some embodiments, welding the electronic component to the first connection pad via the pin and the first solder includes:

[0028] The method includes providing a first solder between a pin included in each electronic component and the first connection pad, and reacting the first solder with the first connection pad and the pin, respectively, to weld the at least one electronic component to the first connection pad via the pin and the first solder.

[0029] In some embodiments, when the plurality of electronic components includes at least one first electronic component, the method of fabrication further comprises:

[0030] The method further includes detecting a connection state between the plurality of electronic components and the first connection pad.

[0031] If the connection state between the second electronic component and the first connection pad does not meet the requirement, the second electronic component is replaced, and the second electronic component is substituted with the first electronic component.

[0032] In some embodiments, replacing the second electronic component and substituting the first electronic component includes:

[0033] removing the second electronic component and forming a groove in a surface of the first connection pad that faces away from the base substrate.

[0034] The method includes providing a second solder in the groove, welding a pin included in the first electronic component to the first connection pad via the second solder, and forming the first intermetallic compound between the second solder and at least a sidewall of the groove. [Brief description of the drawings]

[0035] In order to more clearly describe the technical solutions of the present disclosure, the drawings used in some embodiments of the present disclosure will be briefly described below. It is clear that the drawings in the following description are only a part of some embodiments of the present disclosure. Those skilled in the art can obtain other drawings based on these drawings. In addition, the drawings in the following description can be regarded as schematic diagrams, and do not limit the actual dimensions of the products, the actual flow of the methods, the actual timing of the signals, etc., of the embodiments of the present disclosure.

[0036] [Figure 1] 1 is a cross-sectional view illustrating a structure of a functional backplane according to some embodiments.

[0037] [Figure 2A] 4A to 4C are cross-sectional views illustrating structures of first connection pads according to some embodiments.

[0038] [Figure 2B] 11 is a cross-sectional view illustrating another structure of a first connection pad according to some embodiments.

[0039] [Figure 2C] 11 is a cross-sectional view illustrating another structure of a first connection pad according to some embodiments.

[0040] [Figure 2D] 11 is a cross-sectional view illustrating another structure of a first connection pad according to some embodiments.

[0041] [Figure 2E] 11 is a cross-sectional view illustrating another structure of a first connection pad according to some embodiments.

[0042] [Figure 2F] 11 is a cross-sectional view illustrating another structure of a first connection pad according to some embodiments.

[0043] [Figure 2G] 11 is a cross-sectional view illustrating another structure of a first connection pad according to some embodiments.

[0044] [Figure 2H] 11 is a cross-sectional view illustrating another structure of a first connection pad according to some embodiments.

[0045] [Figure 2I] 11 is a cross-sectional view illustrating another structure of a first connection pad according to some embodiments.

[0046] [Figure 2J] 11 is a cross-sectional view illustrating another structure of a first connection pad according to some embodiments.

[0047] [Figure 2K] FIG. 13 is a cross-sectional view illustrating a structure of yet another first connection pad according to some embodiments of the present disclosure.

[0048] [Figure 2L]FIG. 13 is a cross-sectional view illustrating yet another structure of a first connection pad according to some embodiments.

[0049] [Diagram 3] 4A and 4B are structural diagrams of connections between a first connection pad and a pin according to some embodiments.

[0050] [Figure 4] FIG. 2 is a top view of a first wiring layer and a first connection pad according to some embodiments.

[0051] [Diagram 5] 5 is a cross-sectional view taken along the direction AA′ in FIG. 4 according to some embodiments.

[0052] [Figure 6] 1 is a cross-sectional view showing a structure in which a circuit board and an electronic component are electrically connected to a wiring board according to some embodiments.

[0053] [Figure 7A] 4A and 4B are structural diagrams of connections between a first connection pad and a pin according to some embodiments.

[0054] [Figure 7B] FIG. 11 is a structural diagram of a connection between another first connection pad and a pin according to some embodiments.

[0055] [Figure 7C] FIG. 13 is a structural diagram of yet another connection between a first connection pad and a pin according to some embodiments.

[0056] [Figure 8] 1 is a flow chart of a method for manufacturing a functional backplane according to some embodiments.

[0057] [Figure 9] 1 is a flow chart illustrating a process for forming a first intermetallic compound between a first solder and at least a first reference protective layer according to some embodiments.

[0058] [Figure 10] 1 is a flowchart of replacing a second electronic component with a first electronic component according to some embodiments. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0059] Hereinafter, the technical solutions according to some embodiments of the present disclosure will be described clearly and completely with reference to the drawings. It is clear that the described embodiments are only some of the embodiments of the present disclosure, and are not all of the embodiments. Based on the embodiments of the present disclosure, all other embodiments obtained by those skilled in the art shall be within the scope of the present disclosure.

[0060] Unless the context requires otherwise, throughout this specification and claims, the term "comprise" and other forms, such as the third person singular "comprises" and the present participle form "comprising" should be interpreted in an open, inclusive sense, i.e., "including but not limited to." In the description of the specification, the terms "one embodiment," "some embodiments," "exemplary embodiments," "examples," "specific examples," "some examples," and the like, are intended to indicate that a particular feature, structure, material, or characteristic associated with the embodiment or example is included in at least one embodiment or example of the present disclosure. General expressions of the above terms do not necessarily refer to the same embodiment or example. Moreover, a particular feature, structure, material, or characteristic described may be included in any one or more embodiments or examples in any suitable manner.

[0061] In the following, the terms "first" and "second" are for descriptive purposes only and should not be understood as indicating or implying the relative importance or quantity of the indicated technical features. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of the feature. In the description of the embodiments of the present disclosure, "plurality" means two or more, unless otherwise specified.

[0062] "At least one of A, B, and C" has the same meaning as "at least one of A, B, or C," and all include the following combinations of A, B, and C: A only, B only, C only, a combination of A and B, a combination of A and C, a combination of B and C, and a combination of A, B, and C.

[0063] "A and / or B" includes the three combinations of A only, B only, and a combination of A and B.

[0064] In this specification, the use of "applied to" or "disposed to" is intended to be open and inclusive language and does not exclude devices adapted or arranged to perform additional tasks or steps.

[0065] Some embodiments of the present disclosure provide a light emitting device. The light emitting device includes a functional backplane. Of course, other components may also be included. For example, the light emitting device may include a circuit used to provide an electrical signal to the functional backplane and drive the functional backplane. The circuit may be called a control circuit, and may include a circuit board and / or an IC (Integrated Circuit) electrically connected to the functional backplane.

[0066] In some embodiments, the light-emitting device may be a lighting device, in which the light-emitting device is used as a light source to realize a lighting function, for example, the light-emitting device may be a backlight module in a liquid crystal display device, a lamp for internal or external lighting, or various signal lamps, etc.

[0067] In some other embodiments, the light emitting device may be a display device. In this case, the functional backplane is a display substrate and is used to realize the function of displaying an image (i.e., a screen). The light emitting device may include a display or a product including a display. Here, the display may be a flat panel display (FDP) or a micro display, etc. Depending on whether a user can see the back of the display, the display may be classified as a transparent display or an opaque display. Depending on whether the display is folded or rolled up, the display may be classified as a flexible display or a normal display (which may be called a rigid display). Exemplarily, the product including a display may include a computer display, a television, a signboard, a laser printer with a display function, a telephone, a mobile phone, a PDA (Personal Digital Assistant), a notebook computer, a digital camera, a portable camera video recorder, a viewfinder, a vehicle, a large area wall, a theater screen or a stadium signboard, etc.

[0068] STM is a surface mounting technology (abbreviation of Surface Mounted Technology), which is the most popular technology and process in the electronic assembly industry. It is a technology in which electronic components with pins are placed on the surface of a base substrate having circuits and connection pads (also called pads), and then assembled by welding using methods such as reflow soldering and dip soldering. In order to complete the fixed connection between the electronic components and the connection pads, it is necessary to provide solder on the connection pads that are to be electrically connected to the electronic components on the base substrate, or to provide solder on the pins of the electronic components. Next, the electronic components are aligned and placed in contact with the connection pads, and the solder is melted at a high temperature of, for example, 230°C to 260°C to obtain good wettability, and then cooled rapidly to reduce the temperature, thereby realizing the fixed connection or welding between the electronic components and the connection pads. The material of the connection pads is generally copper, but since copper is easily oxidized, it is necessary to surface treat the connection pads to prevent the oxidation of copper. The surface treatment method of the connection pads includes forming a copper alloy layer on the surface of the connection pads to prevent the oxidation of copper. This allows the electronic component to be directly welded to the copper alloy layer via the solder. However, the inventors of the present disclosure have found that during the reflow soldering process, an intermetallic compound (abbreviated as Intermetallic Compound, IMC) may be formed between the solder, the copper alloy layer, and the connection pad, and the thickness and composition of the intermetallic compound are functionally related to the time, temperature, and application conditions of the welding process, and change the internal stress of the material bonding portion, and generally, as the thickness of the intermetallic compound increases, the internal stress gradually increases, causing the contact portion (welded point) between the electronic component and the conductive gasket to become brittle and even causing breakage, thereby affecting the connection strength and reliability between the two.

[0069] Specifically, during the reflow soldering process, intermetallic compounds may be rapidly generated between the solder, the copper alloy layer, and the connection pad, and the copper in the copper alloy layer and the connection pad may form a "temporarily stable" compound of the CuxSny series with the tin in the solder when the solder is in direct contact with the copper alloy layer and the connection pad. Here, in CuxSny, x=3, 4, 5, 6, y=2, 3, 4, 5, and the thickness and thickness ratio of these CuxSny series compounds change according to the temperature, time, environment, and use conditions of the welding process. Here, the Cu3Sn2 compound is located in the area farthest from the solder, and the Cu6Sn5 compound is located in the area closest to the solder. The weldability of the Cu3Sn2 compound is very poor, and although the Cu6Sn5 compound has weldability, its thickness is relatively thin, so the connection strength of the welding point is low and the reliability is poor.

[0070] In addition, when the electronic components are incompletely welded or misaligned, a lateral shear force needs to be applied to remove the electronic components and firmly weld them back to the correct position. In the process of removing the electronic components, the connection pads may be damaged, so that the connection pads cannot be welded to the electronic components again.

[0071] In some embodiments of the present disclosure, a functional backplane 100 is provided. As shown in FIG. 1, the functional backplane 100 includes a wiring board 10 and at least one electronic component 20. The at least one electronic component 20 is disposed on the wiring board 10. Each electronic component 20 includes a pin 30. The electronic component 20 is electrically connected to the wiring board 10 via the pin 30. The electronic component 20 may include, but is not limited to, a micro light-emitting diode, a microchip, a microsensor, a microdrive, etc.

[0072] Specifically, taking the example of the electronic component 20 having two pins, the pin 30 may include a cathode pin 30a and an anode pin 30b. The wiring board 10 includes a base substrate 1 and a plurality of first connection pads 2. The base substrate 1 has a device region A. The plurality of first connection pads 2 are provided on the base substrate 1 and located in the device region A. The electronic component 20 is electrically connected to the first connection pads 2 via the pins 30 (the cathode pin 30a and the anode pin 30b) and the first solder X1 (including an alloy whose base material is tin, for example, a tin-silver-copper alloy), thereby realizing an electrical connection between the electronic component 20 and the wiring board 10.

[0073] Taking the electronic component 20 as an example of a micro light-emitting diode, specifically, it refers to a light-emitting diode having a size of about 50 microns to 500 microns.

[0074] For backlight applications, when the electronic component 20 is a micro light-emitting diode, a plurality of micro light-emitting diodes can be arranged in a matrix and combined with local dimming technology to achieve better brightness uniformity and higher color contrast within a smaller light mixing distance, and further realize ultra-thin, high color rendering, high contrast and high brightness of the terminal product, which is superior to the conventional direct-lit or edge-lit backlight architecture. In addition, a plurality of micro light-emitting diodes can be provided on a flexible substrate, and further cooperate with a passive display panel having a curved surface to realize a curved display realized by a technology like an organic light-emitting diode while ensuring image quality. For display applications, the micro light-emitting diodes include micro light-emitting diodes that emit three colors (e.g., red, green, blue), and the three-color micro light-emitting diodes have higher brightness and contrast.

[0075] In some embodiments, as shown in FIGS. 2A to 2L, the plurality of first connection pads 2 include at least one electrical connection layer 21. Each electrical connection layer 21 includes a body material layer 211 and at least one protective layer 212, and the at least one protective layer 212 is provided on a side of the body material layer 211 that is farther from the base substrate. The at least one protective layer 212 includes a first reference protective layer 212A. The first reference protective layer 212A is the protective layer 212 that is farthest from the base substrate 1 among the at least one protective layer 212. The material of the body material layer 211 includes copper. The at least one electrical connection layer 21 includes a first electrical connection layer 21A. The first electrical connection layer 21A is the electrical connection layer 21 that is farthest from the base substrate 1 among the at least one electrical connection layer 21. In at least one protective layer 212 included in the first electrical connection layer 21A, a first intermetallic compound can be formed between the material of at least the first reference protective layer 212A and the first solder.

[0076] Here, the multiple first connection pads 2 include at least one electrical connection layer 21, and each electrical connection layer 21 includes a main material layer 211 and at least one protective layer 212, and the at least one protective layer 212 is provided on the side of the main material layer 211 that is distant from the base substrate 1. As can be seen from this, in any of the first connection pads 2, the number of layers of the electrical connection layer 21 is one or multiple, and each electrical connection layer 21 includes one main material layer 211 and one or multiple protective layers 212, and the one or multiple protective layers 212 are provided on the side of the main material layer 211 that is distant from the base substrate 1.

[0077] Here, when the number of layers of the electrical connection layer 21 is one, the electrical connection layer 21 is the first electrical connection layer 21A. At this time, the first electrical connection layer 21A has two possible situations according to which it can include one or multiple protective layers 212. In the first situation, as shown in FIG. 2A and FIG. 2B, the first electrical connection layer 21A includes one protective layer 212, and the protective layer 212 is the first reference protective layer 212A. In the second situation, as shown in FIG. 2C to FIG. 2G, the first electrical connection layer 21A includes multiple protective layers 212, and the protective layer 212 farthest from the base substrate 1 among the multiple protective layers 212 is the first reference protective layer 212A. When the number of layers of the electrical connection layer 21 is multiple, the first electrical connection layer 21A is the electrical connection layer 21 farthest from the base substrate 1 among the multiple electrical connection layers 21, as shown in FIG. 2H to FIG. 2L. At this time, there are two possible situations depending on whether the first electrical connection layer 21A includes one or multiple protective layers 212. In the first situation, as shown in Figures 2H to 2L, the first electrical connection layer 21A includes one protective layer 212, and the protective layer 212 is a first reference protective layer 212A. In the second situation, the first electrical connection layer 21A includes multiple protective layers 212, and the protective layer 212 of the multiple protective layers 212 that is the furthest from the base substrate 1 is the first reference protective layer 212A.

[0078] As a result, in each first connection pad 2, the first reference protective layer 212A included in the first electrical connection layer 21A is the protective layer 212 exposed to the outside among the at least one protective layer 212 included in the at least one electrical connection layer 21. In the at least one protective layer 212 included in the first electrical connection layer 21A, the material of at least the first reference protective layer 212A and the first solder can form a first intermetallic compound, and therefore, in the process of welding the pin 30 of the electronic component 20 and the first connection pad 2 using the first solder, the first solder and at least the first reference protective layer 212A included in the first electrical connection layer 21A form a first intermetallic compound, and the first solder and the pin 30 form a second intermetallic compound, thereby realizing welding.

[0079] Compounds formed by metals and metals or metals and metalloids (e.g. H, B, N, S, P, C, Si, etc.) are called intermetallic compounds (IMC). The elements in an intermetallic compound are bonded together by metallic bonds and retain their metallic properties. Intermetallic compounds are the product of interface reactions. In the process of welding the pin 30 of the electronic component 20 to the first connection pad 2 using the first solder, the first solder is first melted under heating, and then the material of the first reference protective layer 212A contained in the first electrical connection layer 21A in the first connection pad 2 is melted, and at the same time, the material of the pin 30 is also melted. Then, the metal atoms in the first solder react with the metal atoms in the first reference protective layer 212A and the metal atoms in the pin 30, respectively, while diffusing, to form a first intermetallic compound with the metal atoms in the first reference protective layer 212A and form a second intermetallic compound with the metal atoms in the pin 30. At the same time, as the first solder continues to diffuse, the metal atoms in the first solder and the metal atoms in the body material layer can also form the first intermetallic compound.

[0080] It is understood that the rate of formation of intermetallic compounds is related to the composition, melting point, temperature, and reaction time of the material. In addition, as the diffusion of two metals with different diffusion coefficients progresses, the original contact interface between the film layer in which they are present may move. In general, the interface moves toward the film layer in which the metal with the larger diffusion coefficient is present. In some cases, the film layer in which the metal with the larger diffusion coefficient is present may also form cavities or voids of nanometer or micron size.

[0081] Through research, the inventors have found that: if the first connection pad 2 includes an electrical connection layer 21 such as the first electrical connection layer 21A, and the first electrical connection layer 21A includes only the first reference protective layer 212A, and the material of the first reference protective layer 212A includes a copper-nickel alloy, the mass percentage of nickel in the copper-nickel alloy is less than 40%, and the thickness of the first reference protective layer 212A is 500 Å, during the process of welding the pin 30 of the electronic component 20 to the first connection pad 2 using the first solder, as the first solder diffuses into the first reference protective layer 212A, the first reference protective layer 212A and the first reference protective layer 212A will be bonded to the first gold. After the first solder and the first reference protective layer 212A form a first intermetallic compound, the first solder quickly diffuses into the body material layer 211 included in the first electrical connection layer 21A and forms a first intermetallic compound with the body material layer 211 included in the first electrical connection layer 21A, so that the thickness of the first intermetallic compound at the welding point interface becomes too thick, the welding point becomes brittle, and the mechanical strength is deteriorated. As a result, the welding point is prone to brittle cracking at the interface at room temperature, and when a welding defect (for example, incomplete welding (pseudo soldering) or a positional deviation of the electronic component 20 occurs), repair is required. In the process of removing the electronic component 20, the body material layer 211 included in the first electrical connection layer 21A is also easily removed, so that the copper of the body material layer 211 included in the first electrical connection layer 21A is missing, and repair cannot be realized.

[0082] In the embodiment of the present disclosure, the first connection pad 2 includes at least one electrical connection layer 21, the at least one electrical connection layer 21 includes a first electrical connection layer 21A, and the first electrical connection layer 21A includes at least one protective layer 212. Therefore, by rationally setting the number of layers, the material and / or thickness of each layer, etc. of the protective layer 212 included in the first electrical connection layer 21A, the reaction rate between the first solder and the first reference protective layer 212A can be slowed down, thereby blocking the diffusion of the first solder into the main body material layer 211 included in the first electrical connection layer 21A, thereby preventing the thickness of the first intermetallic compound at the welding point interface from being too thick and causing copper loss in the main body material layer 211, and improving the repairability rate.

[0083] In some embodiments, as shown in FIGS. 2A to 2L, the thickness d1 of the body material layer 211 included in the first electrical connection layer 21A is not less than 3000 Å and not more than 50000 Å.

[0084] That is, in these embodiments, the thickness d1 of the body material layer 211 included in the first electrical connection layer 21A can take a value within the range of 3000 Å to 50000 Å.

[0085] Optionally, the thickness d1 of the body material layer 211 included in the first electrical connection layer 21A is 6000 Å.

[0086] Here, the material of the first reference protective layer 212A included in the first electrical connection layer 21A is not particularly limited. The material of the first reference protective layer 212A included in the first electrical connection layer 21A may be any material capable of forming a first intermetallic compound with the first solder. For example, the material of the first reference protective layer 212A included in the first electrical connection layer 21A may include a metal material and / or a nonmetal material.

[0087] In some embodiments of the present disclosure, the material of the first reference protective layer 212A included in the first electrical connection layer 21A is a single metal or a metal alloy.

[0088] In some embodiments, the elemental metal may include any one of Cu, Ni, Fe, Ag, and Au. The metal alloy may include any one of Cu, Ni, Fe, Ag, and Au, or a multi-elemental metal alloy such as a nickel alloy, a silver alloy, a copper alloy, and the like.

[0089] In some examples, the metal alloy may be a nickel alloy, which is less expensive and more readily available than copper, iron, silver, and gold alloys.

[0090] Here, the nickel alloy may be any binary or ternary alloy containing nickel, for example, a binary or ternary alloy consisting of Ni and Cu, Al, La, Pb, Co, Ag, Sb, In, Ga, Zn, Ta, Ru, Ti, Bi, Nd, Pd, Mg, Li, Sc, Y, Zr, Sr, Rb, Cs, Hf, Mn, Cr, Ge, Tl, Ce, Pr, etc.

[0091] In some examples, the nickel alloy includes a nickel vanadium alloy, a nickel aluminum alloy, a nickel tungsten alloy, a copper nickel titanium alloy, and a copper nickel aluminum alloy. The copper alloy includes any one of a copper nickel alloy and a copper magnesium aluminum alloy. In the nickel vanadium alloy, the mass percentage of vanadium may be, for example, 7% or 40%. In the nickel aluminum alloy, the mass percentage of aluminum may be, for example, 20%. In the nickel tungsten alloy, the mass percentage of tungsten may be, for example, 49%.

[0092] Of course, in some embodiments, the material of the first reference protective layer 212A included in the first electrical connection layer 21A may be doped with other elements (e.g., other metallic or non-metallic elements not listed above).

[0093] Here, in the above nickel alloy, the mass percentage of nickel in the nickel alloy may be any value. For example, in the nickel-copper alloy, the mass percentage of nickel may be 5% to 99%. In the nickel-aluminum alloy, the mass percentage of nickel may also be 5% to 99%.

[0094] Here, the thickness d2 of the single or multiple protective layers 212 included in the first electrical connection layer 21A is not particularly limited, and can be reasonably set according to need in practical operation, ensuring that the first intermetallic compound formed by the first solder and at least the first reference protective layer 212A during welding has a sufficient thickness and improves the robustness of the weld.

[0095] In some embodiments, as shown in FIGS. 2A to 2L, the thickness d2 of each of the protective layers 212 included in the first electrical connection layer 21A is not less than 300 Å and not more than 30,000 Å.

[0096] In some embodiments, the thickness d2 or material of at least one protective layer 212 included in the first electrical connection layer 21A is further configured to block diffusion of the first solder into the body material layer 211 included in the first electrical connection layer 21A.

[0097] In these embodiments, the reaction rate between the at least one protective layer 212 included in the first electrical connection layer 21A and the first solder can be adjusted by selecting the thickness d2 or material of the at least one protective layer 212 included in the first electrical connection layer 21A. For example, the thickness d2 of the at least one protective layer 212 included in the first electrical connection layer 21A can be increased, and the diffusion depth of the first solder in the first electrical connection layer 21A can be reduced within the same reaction time, thereby blocking the diffusion of the first solder into the main body material layer 211 included in the first electrical connection layer 21A and improving the repairability rate.

[0098] In some embodiments, as shown in FIG. 3, when the material of the first reference protective layer 212A included in the first electrical connection layer 21A includes copper or a copper-nickel alloy, and the mass ratio of nickel in the copper-nickel alloy is less than 40%, the thickness d21 of the first reference protective layer 212A included in the first electrical connection layer 21A is 1000 Å or more. Exemplarily, the thickness d21 of the first reference protective layer 212A included in the first electrical connection layer 21A may be 3000 Å. When the material of the first reference protective layer 212A included in the first electrical connection layer 21A includes a copper-nickel alloy, and the mass ratio of nickel in the copper-nickel alloy is 40% or more, the thickness d21 of the first reference protective layer 212A included in the first electrical connection layer 21A is 800 Å or more. Exemplarily, the thickness d21 of the first reference protective layer 212A included in the first electrical connection layer 21A may be 1000 Å. When the material of the first reference protective layer 212A included in the first electrical connection layer 21A does not contain copper, the thickness d21 of the first reference protective layer 212A included in the first electrical connection layer 21A is 300 Å to 30,000 Å. For example, the thickness d21 of the first reference protective layer 212A included in the first electrical connection layer 21A may be 500 Å.

[0099] In these embodiments, by limiting the material and thickness d21 of the first reference protective layer 212A included in the first electrical connection layer 21A within the above range, it is possible to block diffusion of the first solder X1 into the main body material layer 211 included in the first electrical connection layer 21A. Therefore, after removing the electronic component 20, the main body material layer 211 included in the first electrical connection layer 21A is not completely removed, and the repairability rate can be improved.

[0100] In some examples, when the material of the first reference protective layer 212A included in the first electrical connection layer 21A includes a copper-nickel alloy, and the mass ratio of nickel in the copper-nickel alloy is less than 40%, by controlling the thickness d21 of the first reference protective layer 212A included in the first electrical connection layer 21A to 10,000 Å, after one welding using the first solder, the thickness of the first intermetallic compound formed by the first solder and the main body material layer 211 included in the first electrical connection layer 21A is about 15,000 Å. When the thickness d21 of the first reference protective layer 212A included in the first electrical connection layer 21A is increased to 40,000 Å, the thickness of the first intermetallic compound formed by the first solder and the main body material layer 211 included in the first electrical connection layer 21A is reduced to 10,000 Å.

[0101] As can be seen from the above, when the material of the first reference protective layer 212A contained in the first electrical connection layer 21A is the same, by performing a thickness increasing process to thicken the first reference protective layer 212A contained in the first electrical connection layer 21A, the thickness of the first intermetallic compound IMC1 at the weld point interface can be reduced, thereby improving the repairability rate.

[0102] 2A to 2L, in some embodiments, when the material of the first reference protective layer 212A included in the first electrical connection layer 21A contains copper or a copper-nickel alloy, the thickness d21 of the first reference protective layer 212A has a value between 300 Å and 600 Å. When the material of the first reference protective layer 212A included in the first electrical connection layer 21A does not contain copper, the thickness d21 of the first reference protective layer 212A has a value between 300 Å and 3000 Å.

[0103] In these embodiments, by limiting the material and thickness d21 of the first reference protective layer 212A included in the first electrical connection layer 21A to within the above-mentioned range, it is possible to block diffusion of the first solder X1 into the main material layer 211 included in the first electrical connection layer 21A. Therefore, after removing the electronic component 20, the main material layer 211 included in the first electrical connection layer 21A is not completely removed, and the repairability rate can be improved.

[0104] In some embodiments, as shown in FIG. 2B, the diffusion depth D1 of the first solder in at least one protective layer 212 is equal to or greater than the thickness d21 of the first reference protective layer 212A included in the first electrical connection layer 21A.

[0105] In these embodiments, by controlling the diffusion depth D1 of the first solder in at least one protective layer 212 within the above range, the repairability rate can be improved and the first intermetallic compound formed by the first solder and the first electrical connection layer 21A can be ensured to have a sufficient thickness, thereby improving the robustness and electrical conductivity of the weld.

[0106] In some embodiments, as shown in FIGS. 2C to 2G, the at least one protective layer 212 includes at least two protective layers 212, and the at least one protective layer 212 further includes the second reference protective layer 212A and a second reference protective layer 212B. The second reference protective layer 212B is located between the first reference protective layer 212A and the base substrate 1. A material of the second reference protective layer 212B and the first solder can form a first intermetallic compound, or a material of the second reference protective layer 212B and the first solder cannot form a first intermetallic compound.

[0107] In these examples, if the material of the second reference protective layer 212B can form a first intermetallic compound with the first solder, the material of the second reference protective layer 212B can be the same as or different from the material of the first reference protective layer 212A. If the material of the second reference protective layer 212B cannot form a first intermetallic compound with the first solder, the material of the second reference protective layer 212B can be selected from one of molybdenum, titanium, and aluminum, or an alloy including one or more of the elements of molybdenum, titanium, and aluminum, such as a molybdenum alloy.

[0108] Here, if the material of the second reference protective layer 212B contained in the first electrical connection layer 21A cannot form a first intermetallic compound with the first solder, in order to improve the repairability rate, the above explanation can be referred to for the selection of the material and thickness d21 of the first reference protective layer 212A contained in the first electrical connection layer 21A, and a detailed explanation will not be given here.

[0109] When the material of the second reference protective layer 212B can form a first intermetallic compound with the first solder, if the material and thickness d21 of the first reference protective layer 212A are not sufficient to ensure the repairability rate, the material and thickness d22 of the second reference protective layer 212B can also be set to ensure the repairability rate. For example, when the material of the first reference protective layer 212A includes a copper-nickel alloy, and the mass ratio of nickel in the copper-nickel alloy is less than 40%, and the thickness d21 of the first reference protective layer 212A is 500 Å or less, the material and thickness d22 of the second reference protective layer 212B can be selected to adjust the thickness of the first intermetallic compound formed by the first solder and the second reference protective layer 212B in the same manner, so that the thickness of the first intermetallic compound formed by the first solder and the main body material layer 211 included in the first electrical connection layer 21A can be reduced, and the repairability rate can be improved.

[0110] In some embodiments, as shown in Figures 2C-2G, the material of the second reference protective layer 212B can form a first intermetallic compound with the first solder. The materials of the at least two protective layers 212 are different. Or, as shown in Figures 2C-2G, the thickness d2 of at least one protective layer 212 is greater than 500 Å, or the sum of the thicknesses d2 of the at least two protective layers is greater than 500 Å.

[0111] In these embodiments, the number of layers in the electrical connection layer 21 is one, the electrical connection layer 21 includes only one protective layer 212, the material of the protective layer 212 is a copper-nickel alloy, the mass percentage of nickel is less than 40%, and the thickness of the protective layer 212 is 500 Å. In comparison, by selecting the material of at least two protective layers 212, for example, at least one protective layer 212 (e.g., the first reference protective layer 212A or the second reference protective layer 212B) is selected to be a material that is less likely to form a first intermetallic compound with the first solder (compared to a copper alloy), and the thickness of the first intermetallic compound is reduced, the diffusion of the first solder to the main body material layer 211 included in the first electrical connection layer 21A can be blocked.

[0112] Alternatively, the number of layers of the electrical connection layer 21 is one, and the electrical connection layer 21 includes only one protective layer 212, the material of the protective layer 212 is a copper-nickel alloy, and the mass ratio of nickel is less than 40%, and the thickness of the protective layer 212 is 500 Å. By reasonably setting the material and thickness d2 of the at least two protective layers 212, for example, the material of the at least two protective layers 212 is selected to be the same as the material of the protective layer 212, but the sum of the thicknesses d21 is relatively thick, for example For example, by selecting the sum of the thickness d21 of the first reference protective layer 212A and the thickness d22 of the second reference protective layer 212B to be 1000 Å, or by selecting the material of at least one of the at least two protective layers 212 to be different from the material of the protective layer 212 in the related art, and selecting the thickness d2 to be the same as or different from the thickness of the protective layer 212, the diffusion of the first solder into the main body material layer 211 included in the first electrical connection layer 21A can be similarly blocked.

[0113] In some embodiments, the materials of the at least two protective layers 212 are different, with many possible scenarios.

[0114] In the first situation, at least two protective layers 212 contain different types of elements.

[0115] In the second situation, the types of elements contained in at least two protective layers 212 are the same, but the ratios of the elements are different.

[0116] In the third situation, the types and ratios of the base elements contained in the at least two protective layers 212 are the same, and at least one protective layer 212 further contains a doping material doped into the base element contained in the at least one protective layer 212.

[0117] In the first situation, the different types of elements contained in at least two protective layers 212 refer to that each protective layer 212 may contain one element or multiple elements. When each protective layer 212 contains one element, the material of each protective layer 212 is a single element. When each protective layer 212 contains multiple elements, the material of each protective layer 212 may be an alloy. When the first partial protective layer 212 (for example, the number of layers of the protective layer 212 is three, and the first partial protective layer 212 is the first reference protective layer 212A) contains one element and the second partial protective layer 212 (for example, the remaining two protective layers 212 other than the first reference protective layer 212A of the three protective layers 212) contains multiple elements, the material of the first partial protective layer 212 may be a single element, and the material of the second partial protective layer 212 may be an alloy.

[0118] Here, when each protective layer 212 is a single element, at least two protective layers 212 are selected from different single elements. Here, taking the case where each protective layer 212 is selected from a single metal as an example, when the number of layers of the protective layer 212 is three, the three protective layers 212 can be selected from three different single metal elements. Exemplarily, the materials of the three protective layers 212 may be single copper, single nickel, and single silver. When each protective layer 212 is an alloy, at least two protective layers 212 are selected from different alloys. Here, taking the case where each protective layer 212 is selected from a metal alloy as an example, when the number of layers of the protective layer 212 is three, at least one metal element is different among the two metal elements contained in each of the three protective layers 212. Exemplarily, the materials of the three protective layers 212 may be copper-nickel alloy, copper-silver alloy, and nickel-silver alloy. In the at least two protective layers 212, when the first partial protective layer 212 is selected from a simple metal and the second partial protective layer 212 is selected from an alloy, at least one metal element of the alloy contained in each of the two partial protective layers 212 is different. Exemplarily, the materials of the three protective layers 212 may be simple copper, a copper-nickel alloy, and a copper-silver alloy. In the at least two protective layers 212, when the first partial protective layer 212 is selected from an alloy and the second partial protective layer 212 is selected from a simple metal, at least one metal element of the alloy contained in each of the two partial protective layers 212 is different. Exemplarily, the materials of the three protective layers 212 may be simple copper, simple nickel, and a copper-nickel alloy.

[0119] In the second situation, the at least two protective layers 212 contain the same elements and have different ratios of the elements, which means that the elements in each protective layer 212 are multiple and the elements are the same, but the mass ratios of the elements are different. In addition, taking the case where each protective layer 212 is selected from a metal alloy as an example, when the number of protective layers 212 is three, the material of each of the three protective layers 212 may be a copper-nickel alloy, but the mass ratios of copper and nickel in the at least two protective layers 212 are different.

[0120] In the third situation, the base element refers to an element that is contained in a relatively large amount (e.g., mass percentage) of all elements in the protective layer 212. In contrast to the base element, the doping material refers to an element that is contained in a relatively small amount (e.g., mass percentage) in the protective layer 212. The types and percentages of the base elements contained in at least two protective layers 212 are the same, and at least one protective layer 212 further includes a doping material doped into the base element contained in the at least one protective layer 212 means that the types and percentages of the base elements contained in the at least two protective layers 212 are the same, that is, the base materials are the same. Different materials (at least two protective layers 212) can be obtained by doping different types or percentages (e.g., mass) of doping materials into the base material.

[0121] The at least two protective layers 212 have the same type and ratio of base elements, and at least one protective layer 212 further includes a doping material doped into the base element included in the at least one protective layer 212, meaning that when the number of protective layers 212 is two, the types and mass ratios of the base elements included in the two protective layers 212 are the same. The base elements may be copper and nickel in a mass ratio of 40:60, or the base element is nickel alone, in which case one of the two protective layers 212 further includes a doping material (e.g., tungsten) doped into the base element included in the protective layer 212. Alternatively, both of the two protective layers include the doping material, and the types of doping materials included in each of the two protective layers 212 are different, for example, the doping materials included in the two protective layers 212 are tungsten and aluminum, respectively. Alternatively, the type of doping material contained in the two protective layers 212 is the same, and the doping ratios of each are different, for example, the doping material contained in the two protective layers 212 is tungsten, and the mass ratios of tungsten in the protective layers 212 are 5% and 10%, respectively. When the number of protective layers 212 is three, the type and mass ratio of the base element contained in the three protective layers are the same, for example, the base element contained in the three protective layers 212 may be copper and nickel with a mass ratio of 40:60, or the base element is nickel alone, and at least two of the three protective layers 212 all contain the above doping material, and the type of the doping material contained in each of the at least two protective layers 212 is different, for example, the doping material contained in the three protective layers is any three of tungsten, aluminum, neodymium, and vanadium. Alternatively, the type of doping material contained in any two or every two of them may be the same, but the doped mass proportions may be different; for example, the doping material contained in the three protective layers 212 is all tungsten, and the mass proportions of tungsten in the protective layers 212 are 5%, 10%, and 20%, respectively.

[0122] Here, if the base material of each protective layer 212 is a metal element, those skilled in the art can understand that the material of at least two protective layers 212 can be regarded as a mixture of the base element and the doping material contained in each of them. The difference from the above second situation is that in the above second situation, the contents of the elements contained in the at least two protective layers 212 are equivalent (i.e., there is no significant difference in the contents, for example, the difference in the mass ratio of each element in the same protective layer 212 is 10% or less), whereas in the third situation, the content of the doping material is less than the content of the base element, for example, when the protective layer 212 contains two metal elements, one of which is a base element and the other is an element contained in the doping material, the mass ratio of the doping material in the protective layer 212 may be less than 40%, for example, 10%, 15% or 20%, etc.

[0123] In some embodiments, as shown in Figures 1 and 2C-2G, along a direction gradually approaching the base substrate 1, the diffusion depth of the first solder per unit time in the at least two protective layers 212 gradually decreases and / or the melting point of the material of the at least two protective layers 212 gradually increases.

[0124] In these embodiments, the gradual decrease in the diffusion depth of the first solder per unit time in the at least two protective layers 212 along the direction gradually approaching the base substrate 1 refers to the gradual decrease in the reaction rate between the first solder and the material of the at least two protective layers 212 along the direction gradually approaching the base substrate 1. That is, the rate at which the material of the protective layer 212 and the first solder form the first intermetallic compound decreases as the material approaches the base substrate 1, that is, the material of the protective layer 212 and the first solder are less likely to form the first intermetallic compound. At this time, there are two possible situations. In the first situation, as the material of the protective layer 212 approaches the base substrate 1, the mass ratio of the element capable of forming the first intermetallic compound with the first solder in the material of the protective layer 212 becomes smaller, and / or the reaction ability of the element in the material of the protective layer 212 that forms the first intermetallic compound with the first solder becomes lower. In the second situation, the closer to the base substrate 1, the more severe the conditions for the material of the protective layer 212 and the first solder to form the first intermetallic compound become, for example, the higher the reaction temperature becomes.

[0125] In a first situation, when the reaction conditions are just such that at least two layers of protective layer 212 and the first solder can form a first intermetallic compound, as the material approaches base substrate 1, the rate at which protective layer 212 and the first solder form the first intermetallic compound slows down, thereby blocking the diffusion of the first solder into body material layer 211 included in first electrical connection layer 21A, as the first solder continues to diffuse into protective layer 212, the first solder and protective layer 212 form the first intermetallic compound, and the diffusion rate continues to decrease. In the second situation, the reaction conditions continue to change as the base substrate 1 is approached, for example, the first protective layer 212 forms a first intermetallic compound with the first solder at a first temperature, the second protective layer 212 forms a first intermetallic compound with the first solder at a second temperature, and the third protective layer 212 forms a first intermetallic compound with the first solder at a third temperature, the first temperature being lower than the second temperature, and the second temperature being lower than the third temperature. When three protective layers 212 are fabricated, the first protective layer 212 (i.e., the above-mentioned first protective layer 212) farthest from the base substrate 1 and the first solder can first form a first intermetallic compound at the first temperature when welding is performed. At this time, the first solder does not form a first intermetallic compound with other protective layers 212 (e.g., the second protective layer 212 and the third protective layer 212), or the first solder diffuses slowly into the other protective layers 212, so that the thickness of the first intermetallic compound formed by the first solder and at least two protective layers 212 can be controlled. If repair is required, repair can be achieved by removing only the first intermetallic compound formed by the protective layer 212 (i.e., the first reference protective layer 212A) that is farthest from the base substrate 1 and the first solder, and allowing the first solder and the second protective layer 212 to continue to form the first intermetallic compound under relatively severe conditions (e.g., the second temperature).

[0126] Here, in some examples, the first temperature may be 250°C or more and 300°C or less, the second temperature may be 300°C or more and 350°C or less, and the third temperature may be 350°C or more and 400°C or less.

[0127] According to the formation mechanism of the first intermetallic compound, at a certain temperature, the first solder and at least one element of the protective layer 212 fuse with each other to obtain the first intermetallic compound. As the heating time is extended, the thickness of the first intermetallic compound formed by the first solder and at least one element of the protective layer 212 increases. This heating temperature is related to the melting point of the first solder and the melting point of the material in the protective layer 212. When the first solder is determined, the higher the melting point of the material of the at least two layers of the protective layer 212, the higher the above heating temperature, that is, the higher the above reaction temperature. At this time, similarly to the second situation described above, the thickness of the first intermetallic compound formed by the first solder and at least two protective layers 212 can be controlled, and when repair is required, only the first intermetallic compound formed by the protective layer 212 (i.e., the first reference protective layer 212A) farthest from the base substrate 1 and the first solder is removed, and the first solder and the second protective layer 212 can continue to form the first intermetallic compound under relatively severe conditions (e.g., relatively high temperature), so that repair can be realized. That is, as described above, the melting point of the material of the at least two protective layers gradually increases along the direction gradually approaching the base substrate 1.

[0128] In some embodiments, the doping material may be metallic aluminum.

[0129] That is, in these embodiments, the base element is selected as nickel element, and the doping material is selected as any one of Al, La, Pb, Co, Ag, Sb, In, Ga, Zn, Ta, Ru, Ti, Bi, Nd, etc., for example, metallic aluminum, so that the mass proportion of the doping element in the at least two protective layers 212 is gradually increased along the direction gradually approaching the base substrate 1, thereby achieving the purpose of gradually decreasing the diffusion depth of the first solder per unit time in the at least two protective layers 212.

[0130] Of course, the above is only an example, and it is understood that the base element may be an element contained in the remaining metal element other than copper and nickel. In this case, metallic nickel is most likely to form the first intermetallic compound with the first solder other than copper, so by selecting the base element as an element contained in the remaining metal element other than copper and nickel, such as Al, La, Pb, Co, Ag, Sb, In, Ga, Zn, Ta, Ru, Ti, Bi, Nd, etc., the doping material is selected as metallic nickel, and the mass ratio of metallic nickel in the at least two protective layers 212 is gradually decreased along the direction gradually approaching the base substrate 1, so that the purpose of gradually decreasing the diffusion depth of the first solder per unit time in the at least two protective layers 212 can be achieved.

[0131] In some other embodiments, the doping material may be metallic tungsten.

[0132] When the types and ratios of the base elements contained in the at least two protective layers 212 are the same, at least one protective layer 212 further contains a doping material doped into the base element contained in the at least one protective layer 212, and the melting point of the material of the at least two protective layers 212 gradually increases along the direction gradually approaching the base substrate 1, the base element may be an element contained in the remaining metal element other than tungsten, for example, nickel element. In this case, the mass ratio of metal tungsten in the at least two protective layers 212 is gradually increased along the direction gradually approaching the base substrate 1, thereby achieving the purpose of gradually increasing the melting point of the material of the at least two protective layers 212.

[0133] In some embodiments, as shown in FIGS. 2C to 2G, the proportion of elements capable of forming a first intermetallic compound with the first solder in the at least two protective layers 212 gradually decreases along a direction gradually approaching the base substrate 1.

[0134] For example, the base element contained in the at least two protective layers 212 is nickel element and the doping element is tungsten element. Along the direction gradually approaching the base substrate 1, the mass proportion of tungsten gradually increases, and correspondingly, the mass proportion of nickel gradually decreases.

[0135] Here, the distribution of the thicknesses d2 of the at least two protective layers 212 is not particularly limited, and for example, the thicknesses d2 of the at least two protective layers 212 may be the same or different.

[0136] When the thicknesses d2 of the at least two protective layers 212 are the same, the thicknesses d2 of the at least two protective layers 212 may be 6000 Å. When the thicknesses d2 of the at least two protective layers 212 are different, for example, when the thickness d21 of the first reference protective layer 212A is 500 Å, the thickness d22 of the second reference protective layer 212B may be less than 500 Å or may be greater than 500 Å.

[0137] 2E and 2F, in some embodiments, the thickness d2 of the at least two protective layers 212 gradually increases along the direction gradually approaching the base substrate 1. This makes it easier to control the diffusion of the first solder into the body material layer 211 included in the first electrical connection layer 21A by continuing the diffusion of the first solder downward, which is advantageous in blocking the diffusion of the first solder into the body material layer 211 included in the first electrical connection layer 21A.

[0138] In some examples, as shown in FIGS. 2E and 2F, the thickness d22 of the second reference protective layer 212B is not less than 1000 Å and not more than 30000 Å, and the thickness d21 of the first reference protective layer 212A is not less than 300 Å and not more than 1000 Å.

[0139] In these embodiments, by limiting the thickness d21 of the first reference protective layer 212A and the thickness d22 of the second reference protective layer 212B to within the above range, it is possible to provide the second reference protective layer 212B with the possibility of being used for multiple subsequent repairs while ensuring the subsequent repairability rate, thereby further improving the repairability rate.

[0140] Here, the number of layers of the above-mentioned protective layer 212 is not particularly limited, and as the number of layers of the protective layer 212 increases, the number of subsequent repairs that can be performed increases if the material and thickness d2 of each protective layer 212 are both capable of satisfying one repair.

[0141] Exemplarily, the number of layers of the protective layer 212 may be two, three, four, even five, six or more.

[0142] Considering the impact on production capacity, the number of protective layers 212 is optionally two to three, as shown in FIGS. 2C to 2G.

[0143] Here, when the number of layers of the above-mentioned protective layer 212 is multiple, the material and thickness d2 of at least two of the protective layers 212 are further configured to adjust the diffusion depth of the first solder in the first electrical connection layer 21A, ensuring that the diffusion depth of the first solder in the first electrical connection layer 21A is relatively large, and improving the welding robustness.

[0144] In some embodiments, as shown in FIG. 2G, the diffusion depth D2 of the first solder in the first electrical connection layer 21A is greater than or equal to the thickness d21 of the first reference protective layer 212A included in the first electrical connection layer 21A, and is less than the sum of the thickness d21 of the first reference protective layer 212A included in the first electrical connection layer 21A and the thickness d22 of the second reference protective layer 212B included in the first electrical connection layer 21A.

[0145] In these embodiments, by controlling the diffusion depth D2 of the first solder in the first electrical connection layer 21A within the above range, the robustness of the weld is ensured and subsequent repairs are also possible.

[0146] In some embodiments, as shown in Figures 2H to 2L, the at least one electrical connection layer 21 further includes a second electrical connection layer 21B. The second electrical connection layer 21B is located between the first electrical connection layer 21A and the base substrate 1. As shown in Figures 2H, 2J, 2K, and 2L, the material of the first reference protective layer 212A included in the second electrical connection layer 21B can form a first intermetallic compound with the first solder. Or, as shown in Figure 2I, the material of the first reference protective layer 212A included in the second electrical connection layer 21B cannot form a first intermetallic compound with the first solder.

[0147] Here, when the material of the first reference protective layer 212A included in the second electrical connection layer 21B can form a first intermetallic compound with the first solder, the material of the first reference protective layer 212A included in the second electrical connection layer 21B may be the same as or different from the material of the first reference protective layer 212A included in the first electrical connection layer 21A. When the material of the first reference protective layer 212A included in the second electrical connection layer 21B cannot form a first intermetallic compound with the first solder, the material of the first reference protective layer 212A included in the second electrical connection layer 21B can be selected from one element of molybdenum, titanium, and aluminum, or an alloy containing one or more elements of molybdenum, titanium, and aluminum, for example, a molybdenum alloy, etc. can be selected.

[0148] Here, in case where the material of the first reference protective layer 212A included in the second electrical connection layer 21B cannot form a first intermetallic compound with the first solder, in order to improve the repairability rate, the material and thickness of the main body material layer 211 and at least one protective layer 212 included in the first electrical connection layer 21A can refer to the above description of the at least one electrical connection layer 21 including the first electrical connection layer 21A and the setting of the material and thickness of the at least one protective layer 212 included in the first electrical connection layer 21A, and will not be described in detail here. In case where the material of the first reference protective layer 212A included in the second electrical connection layer 21B can form a first intermetallic compound with the first solder, if the at least one protective layer 212 included in the first electrical connection layer 21A is not sufficient to ensure the repairability rate, the material and thickness d2 of the at least one protective layer 212 included in the second electrical connection layer 21B can also be selected, so as to ensure the repairability rate. For example, the material and thickness of the first electrical connection layer 21A are the same as the material and thickness of one electrical connection layer 21 provided by the related technology, and when the main material layer 211 contained in the first electrical connection layer 21A is completely removed during subsequent repair, the presence of the second electrical connection layer 21B allows the repair to be continued, thereby improving the repairability rate.

[0149] In some embodiments, the material of the first reference protective layer 212A included in the second electrical connection layer 21B can form a first intermetallic compound with the first solder. The material of the first reference protective layer 212A included in the second electrical connection layer 21B is different from the material of the first reference protective layer 212A included in the first electrical connection layer 21A. Or, as shown in FIG. 2I, the thickness d21 of at least one of the first reference protective layer 212A included in the second electrical connection layer 21B and the first reference protective layer 212A included in the first electrical connection layer 21A is greater than 500 Å. Or, as shown in FIGS. 2H, 2J, 2K, and 2L, the sum of the thickness d21 of the first reference protective layer 212A included in the second electrical connection layer 21B and the thickness d21 of the first reference protective layer 212A included in the first electrical connection layer 21A is greater than 500 Å.

[0150] In these embodiments, compared to the related art in which the number of layers in the electrical connection layer 21 is one, the electrical connection layer 21 includes only one protective layer 212, the material of the protective layer 212 is a copper-nickel alloy, the mass percentage of nickel is less than 40%, and the thickness of the protective layer 212 is 500 Å, by selecting the materials of the first electrical connection layer 21A and the second electrical connection layer 21B, for example, the protective layer 212 included in at least one layer of the first electrical connection layer 21A is selected to be a material that is unlikely to form a first intermetallic compound with the first solder, and the thickness of the first intermetallic compound is reduced, subsequent repairs are also possible.

[0151] Alternatively, compared to the related art in which the number of layers of the electrical connection layer 21 is one, the electrical connection layer 21 includes only one protective layer 212, the material of the protective layer 212 is a copper-nickel alloy with a nickel mass percentage of less than 40%, and the thickness of the protective layer 212 is 500 Å, by rationally setting the material and thickness d2 of the at least two electrical connection layers 21, for example, by controlling the thickness d2 of the protective layer 212 included in at least one electrical connection layer 21 in the first electrical connection layer 21A and the second electrical connection layer 21B to be greater than 500 Å, or by controlling the sum of the thicknesses d2 of the protective layers 212 included in the first electrical connection layer 21A and the second electrical connection layer 21B to be greater than 500 Å, subsequent repairs can also be similarly made possible.

[0152] In some embodiments, the material of the first reference protective layer 212A included in the second electrical connection layer 21B is different from the material of the first reference protective layer 212A included in the first electrical connection layer 21A, and there are many possible situations. Specifically, reference may be made to the above description of the case where the electrical connection layer 21 includes the first electrical connection layer 21A and the materials of at least two protective layers 212 included in the first electrical connection layer 21A are different, and a detailed description will not be given here.

[0153] Unlike the above-mentioned electrical connection layer 21 including the first electrical connection layer 21A, which includes only the multi-layer protective layer 212, the at least two electrical connection layers 21 here include, in addition to the protective layer 212, a main material layer 211 for each electrical connection layer 21, and the thickness d1 of the main material layer 211 can achieve the technical effect of enabling one or more subsequent repairs. If the main material layer 211 does not take into account the repair effect, the selection of materials and thickness relationship of the first reference protective layer 212A included in the second electrical connection layer 21B and the first reference protective layer 212A included in the first electrical connection layer 21A can refer to the above description of the selection of materials and thickness relationship of the first reference protective layer 212A and the second reference protective layer 212B included in the first electrical connection layer 21A. When considering that the main body material layer 211 has a repair effect, in actual work, in order to obtain the same technical effect, when the selection of the material of the first reference protective layer 212A included in the second electrical connection layer 21B and the selection of the material of the first reference protective layer 212A included in the first electrical connection layer 21A are the same as the selection of the materials of the first reference protective layer 212A and the second reference protective layer 212B included in the first electrical connection layer 21A, the sum of the thickness d21 of the first reference protective layer 212A included in the second electrical connection layer 21B and the thickness d21 of the first reference protective layer 212A included in the first electrical connection layer 21A may be smaller than the sum of the thickness d21 of the first reference protective layer 212A included in the first electrical connection layer 21A and the thickness d22 of the second reference protective layer 212B when the above-mentioned at least one electrical connection layer 21 includes the first electrical connection layer 21A.

[0154] In some embodiments, the thickness d1 of the body material layer 211 included in the second electrical connection layer 21B is not less than 3000 Å and not more than 50000 Å. That is, in these embodiments, the thickness d1 of the body material layer 211 included in the first electrical connection layer 21A can have a value within the range of 3000 Å to 50000 Å.

[0155] Optionally, the thickness d1 of the body material layer 211 included in the first electrical connection layer 21A is 6000 Å.

[0156] In some embodiments, the thickness d1 of the body material layer 211 included in the second electrical connection layer 21B may be the same as or different from the thickness d1 of the body material layer 211 included in the first electrical connection layer 21A.

[0157] Although the above only describes the case where the at least one electrical connection layer 21 includes the first electrical connection layer 21A and the second electrical connection layer 21B, it is understood that the at least one electrical connection layer 21 may further include a third electrical connection layer and a fourth electrical connection layer, etc., and when the at least one electrical connection layer 21 further includes the third electrical connection layer and the fourth electrical connection layer, the third electrical connection layer and the fourth electrical connection layer may be provided between the second electrical connection layer 21B and the base substrate 1, and the installation manner may refer to the above-mentioned second electrical connection layer 21B, and the selection of materials and thicknesses of the first electrical connection layer 21A, the second electrical connection layer 21B, the third electrical connection layer and the fourth electrical connection layer may also refer to the above-mentioned description of the selection of materials and thicknesses of the multi-layer protective layer 212 (e.g., four or more layers) included in the first electrical connection layer 21A.

[0158] Here, when the at least one electrical connection layer 21 further includes a second electrical connection layer 21B, there is no particular limitation on the thickness distribution of the first reference protective layer 212A included in the at least two electrical connection layers 21. The thicknesses d21 of the first reference protective layers 212A included in the at least two electrical connection layers 21 may be the same or different.

[0159] When the thickness d21 of the first reference protective layer 212A included in at least two electrical connection layers 21 is the same, the thickness d21 of the first reference protective layer 212A included in at least two electrical connection layers 21 may be 6000 Å. When the thickness d21 of the first reference protective layer 212A included in at least two electrical connection layers 21 is different, in each of two adjacent electrical connection layers 21, the thickness d21 of the first reference protective layer 212A included in the lower electrical connection layer 21 may be larger or smaller than the thickness d21 of the first reference protective layer 212A included in the upper electrical connection layer 21. For example, in the first electrical connection layer 21A and the second electrical connection layer 21B, when the thickness d21 of the first reference protective layer 212A included in the first electrical connection layer 21A is 500 Å, the thickness d21 of the first reference protective layer 212B included in the second electrical connection layer 21B may be less than 500 Å or may be greater than 500 Å.

[0160] In some embodiments, as shown in FIG. 2H, the thickness d21 of the first reference protective layer 212A included in the second electrical connection layer 21B is greater than the thickness d21 of the first reference protective layer 212A included in the first electrical connection layer 21A.

[0161] In these embodiments, as the downward diffusion path of the first solder becomes longer, it becomes easier to control the diffusion of the first solder into the body material layer 211 included in the first electrical connection layer 21A, so it is advantageous to block the diffusion of the first solder into the body material layer 211 included in the first electrical connection layer 21A.

[0162] 2H, the thickness d21 of the first reference protective layer 212A included in the second electrical connection layer 21B is not less than 1000 Å and not more than 30000 Å. The thickness d21 of the first reference protective layer 212A included in the first electrical connection layer 21A is not less than 300 Å and not more than 1000 Å.

[0163] In these embodiments, by limiting the thickness d21 of the first reference protective layer 212A included in the second electrical connection layer 21B and the thickness d21 of the first reference protective layer 212A included in the first electrical connection layer 21A to within the above range, it becomes possible for the first reference protective layer 212A included in the second electrical connection layer 21B to be used for multiple subsequent repairs while ensuring the subsequent repairability rate, and the repairability rate can be further improved.

[0164] Optionally, the thickness d21 of the first reference protective layer 212A included in the second electrical connection layer 21B is 500 Å, and the thickness d21 of the first reference protective layer 212A included in the first electrical connection layer 21A is 6000 Å.

[0165] Here, the number of layers of the electrical connection layer 21 is not particularly limited. The number of layers of the electrical connection layer 21 may be 2, 3, 4, or even 5, 6 or more. As the number of layers of the electrical connection layer 21 increases, the number of subsequent repairs that can be performed increases if the material and thickness D of each electrical connection layer 21 can meet one repair.

[0166] Considering the impact on production capacity, the number of electrical connection layers 21 is optionally five or less.

[0167] Here, when the number of layers of the above-mentioned electrical connection layer 21 is multiple, the material and thickness of at least two layers of the electrical connection layer 21 are further configured to adjust the diffusion depth D3 of the first solder in the multi-layer electrical connection layer 21, thereby ensuring that the diffusion depth D3 of the first solder in the multi-layer electrical connection layer 21 is relatively large, and improving the robustness of the welding.

[0168] For example, at least one electrical connection layer 21 includes at least a first electrical connection layer 21A and a second electrical connection layer 21B, and the first electrical connection layer 21A and the second electrical connection layer 21B both include a body material layer 211 and a first reference protective layer 212A, and the materials of the first reference protective layer 212A included in the first electrical connection layer 21A and the second electrical connection layer 21B can both form a first intermetallic compound with a first solder, and the first electrical connection layer 21A and the second electrical connection layer 2 Taking as an example the case where all of the materials of the main body material layer 211 included in 1B are capable of forming a first intermetallic compound with the first solder, as shown in FIG. 2L, the diffusion depth D3 of the first solder in the first electrical connection layer 21A and the second electrical connection layer 21B is greater than or equal to the thickness d21 of the first reference protective layer 212A included in the first electrical connection layer 21A, and is less than or equal to the sum of the thickness D11 of the first electrical connection layer 21A and the thickness d21 of the first reference protective layer 212A included in the second electrical connection layer 21B.

[0169] 1, in some embodiments, the base substrate 1 further includes a binding region B. The wiring substrate 10 further includes a plurality of second connection pads 3. The plurality of second connection pads 3 are provided on the base substrate 1 and located in the binding region B. The plurality of second connection pads 3 are configured to be electrically connected to a circuit board and / or an IC (Integrated Circuit).

[0170] In these embodiments, the second connection pad 3 and the first connection pad 2 are located on the same film layer, and the second connection pad 3 and the first connection pad 2 can be formed using a one-time patterning process. The one-time patterning process refers to forming a required pattern through one-time film formation and photolithography process. The one-time patterning process includes processes such as film formation, exposure, development, etching, and peeling. Since the second connection pad 3 and the first connection pad 2 are located on the same film layer, the number of patterning processes can be reduced, the manufacturing process can be simplified, and the manufacturing cost can be significantly reduced. Here, taking the first connection pad 2 as an example, which includes one electrical connection layer 21, which includes a body material layer 211 and one protective layer 212, the second connection pad 3 and the first connection pad 2 located in the same film layer means that the second connection pad 3 also includes one electrical connection layer 31, which includes a body material layer 311 and one protective layer 312, the body material layer 311 and the body material layer 211 are located in the same film layer, and the protective layer 312 and the protective layer 212 are located in the same film layer. At the same time, since the structure of the second connection pad 3 is the same as that of the first connection pad 2, if the structure of the first connection pad 2 can realize the repairability rate, when a binding error occurs in the binding area B of the base substrate 1, the repair of the circuit board and / or IC (Integrated Circuit) can also be realized.

[0171] 1, the wiring board 10 further includes a first wiring layer 4. The first wiring layer 4 is located between the first connection pad 2 and the base substrate 1. The first wiring layer 4 includes a first sub-metal layer 41, a first sub-wiring layer 42, and a second sub-metal layer 43, which are stacked together. Here, the first connection pad 2 and the second connection pad 3 are electrically connected to different conductive patterns / conductive lines in the second sub-metal layer 43, respectively.

[0172] The material of the first sub-metal layer 41 and the second sub-metal layer 43 includes a molybdenum niobium alloy. The molybdenum niobium alloy has adhesive properties and enhances the adhesive force between the first wiring layer 4 and the base substrate 1. In some cases, a buffer layer can be provided between the base substrate 1 and the first wiring layer 4 to prevent the entire area of ​​the first wiring layer 4 from being too large, causing excessive stress on the base substrate 1 and resulting in fragments. In addition, the first sub-metal layer 41, whose material includes a molybdenum niobium alloy, can also enhance the adhesive force between the first wiring layer 4 and the buffer layer, and the material of the buffer layer is, for example, silicon nitride. At the same time, the second sub-metal layer 43, whose material includes a molybdenum niobium alloy, is connected to the first connection pad 2, and since the molybdenum niobium alloy has adhesive properties, it can ensure the connection stability between the first wiring layer 4 and the first connection pad 2, and since the molybdenum niobium alloy has electrical conductivity, it can ensure the electrical conductivity between the first connection pad 2 and the first wiring layer 4. The material of the first sub-wiring layer 42 can include copper, which has good electrical conductivity, so that the electrical connection between the film layers can be ensured, the resistance of copper is small, so that the current loss during operation can be reduced, and the price of copper is low, so that the manufacturing cost of the array substrate can be reduced. In addition, the second sub-metal layer 43, whose material includes a molybdenum-niobium alloy, can protect the copper of the first sub-wiring layer 42 and prevent the oxidation of copper. The material of the first sub-wiring layer 42 can include copper, which has good electrical conductivity, so that the electrical connection between the film layers can be ensured, the resistance of copper is small, so that the current loss during operation can be reduced, and the price of copper is low, so that the manufacturing cost of the functional backplane can be reduced.

[0173] In some embodiments, as shown in FIG. 1, the thickness of the first sub-wiring layer 42 may be 1 μm to 3 μm.

[0174] In some embodiments, as shown in FIG. 1, the second connection pad 3 is provided in a film layer in the same layer as the first connection pad 2, but of course, the second connection pad 3 may be provided in the same layer as the first wiring layer 4, or the second connection pad 3 may use a film layer in the same layer as both the first wiring layer 4 and the first connection pad 2.

[0175] 1 , the device region A includes a first passivation layer 51, a first planar layer 61, and a second planar layer 62. The first passivation layer 51 is located between the first wiring layer 4 and the first connection pads 2. The first planar layer 61 is located between the first passivation layer 51 and the first connection pads 2. The second planar layer 62 is located on a side of the first connection pads 2 away from the base substrate 1, and covers an area between the first connection pads 2.

[0176] Here, as shown in FIG. 4 and FIG. 5, FIG. 5 is a cross-sectional view along the AA' direction in FIG. 4. The first wiring layer 4 can include an anode wiring 44 and a cathode wiring 45. That is, the anode wiring 44 and the cathode wiring 45 are both provided using a first sub-metal layer 41, a first sub-wiring layer 42, and a second sub-metal layer 43 that are stacked together. In order to reduce the voltage drop (IR Drop), the thickness of the first sub-wiring layer 42 is greater than the thickness of one body material layer 211 in the first connection pad 2, and the thickness of the first sub-wiring layer 42 is positively correlated with the size of the backplane. The first sub-metal layer 41, the first sub-wiring layer 42, and the second sub-metal layer 43 can be sequentially fabricated using a sputtering process. The second sub-metal layer 43 can protect the first sub-wiring layer 42 and prevent the surface of the first sub-wiring layer 42 from being oxidized.

[0177] In some embodiments, as shown in FIG. 5, the first passivation layer 51 includes a portion located between the anode wiring 44 and the cathode wiring 45, which separates adjacent wiring to avoid incorrect electrical connection between the adjacent wiring. The material of the first passivation layer 51 may be silicon nitride, silicon oxide, silicon oxynitride, etc. The first planarization layer 61 covers the area between the anode wiring 44 and the cathode wiring 45. The first planarization layer 61 may be an organic film, which is used to fill the gap area between the wiring, avoids the occurrence of large steps in the subsequent process, ensures that there is no problem of electronic component misalignment when the electronic components are connected to the wiring board, and improves the planarity of the functional backplane, and the first planarization layer 61 can also play an insulating role.

[0178] In some embodiments, as shown in FIG. 5, the first passivation layer 51 may have a thickness between 1000 Angstroms and 4000 Angstroms.

[0179] 1, the wiring board 10 may further include an adhesive layer 7. The adhesive layer 7 is provided between at least one electrical connection layer 21 and the first flat layer 61. The material of the adhesive layer 7 may include a molybdenum-niobium alloy. The molybdenum-niobium alloy has adhesive properties, and therefore the adhesive strength between the first connection pad 2 and the first flat layer 61 may be increased.

[0180] In some other embodiments, the material of the adhesive layer 7 can form a first intermetallic compound with the first solder. The material of the adhesive layer 7 can include a nickel alloy or a copper alloy, for example, a nickel vanadium alloy, a nickel aluminum alloy, or any one of a nickel tungsten alloy, a copper nickel titanium alloy, a copper nickel aluminum alloy, and a copper magnesium aluminum alloy. Here, the mass fraction of nickel in the nickel alloy can be greater than 50%. At this time, after the main body material layer 211 of the electrical connection layer 21 closest to the base substrate 1 in the first connection pad 2 is completely removed, the first solder can also form a first intermetallic compound with the adhesive layer 7, which can also improve the repairability rate.

[0181] 1 and 5, the binding region B further includes a second passivation layer 52, a third planar layer 63, and a fourth planar layer 64. The second passivation layer 52 is located between the first wiring layer 4 and the second connection pad 3. The third planar layer 63 is located between the second passivation layer 52 and the second connection pad 3. The fourth planar layer 64 is located on a side of the second connection pad 3 away from the base substrate 1, and covers an area between the second connection pads 3.

[0182] Here, the third flat layer 63 may be provided in the same layer as the first flat layer 61 to form an integral structure, and the material may be an organic material, for example, resin, which is used for flattening, and is advantageous for the manufacture of subsequent processes (for example, the first connection pad 2, the second connection pad 3, etc.). The fourth flat layer 64 may be provided in the same layer as the second flat layer 62 to form an integral structure, and the material may be an organic material, for example, resin, which is used for flattening, and is advantageous for the manufacture of subsequent processes (for example, the protective layer 8). The second passivation layer 52 may be provided in the same layer as the first passivation layer 51 to form an integral structure, and the material may be silicon oxynitride, silicon nitride, silicon oxide, etc.

[0183] Specifically, as shown in FIG. 5, the second passivation layer 52 may have a thickness of 1000 Å to 9000 Å.

[0184] In some embodiments, the above-mentioned multiple first connection pads can be divided into multiple first connection pad sets. Each first connection pad set is used to connect one electronic component and includes a cathode pad and an anode pad provided as a pair. Here, the body material layer included in the first connection pad welded to the cathode pin of the electronic component is called the cathode pad, and the body material layer included in the first connection pad welded to the anode pin of the electronic component is called the anode pad. As shown in FIG. 4, each first connection pad set includes a cathode pad 211' and an anode pad 211 provided as a pair. The film layer structures included in the cathode pad 211' and the anode pad 211 are the same.

[0185] 6, the circuit board 200 is bound and connected to the second connection pad through the connection part 20. Specifically, the circuit board includes a printed circuit board, a flexible circuit board, an integrated circuit chip, etc., and the material of the connection part may be a thermosetting adhesive or an anisotropic conductive adhesive.

[0186] When specifically implemented, in the above-mentioned functional backplane provided by the embodiment of the present invention, as shown in Figures 4 and 5, the multiple first connection pads are divided into multiple sets of first connection pads, and each set of first connection pads includes a cathode pad 211' and an anode pad 211 arranged as hairs.

[0187] The functional backplane further includes a second wiring layer. The second wiring layer is provided in the same layer as the plurality of first connection pads. The second wiring layer is used to realize a series connection or parallel connection of the plurality of sets of first connection pads, and the second wiring layer is also used to electrically connect to the first wiring layer 4 through via holes penetrating the first flat layer 61 and the first passivation layer 51.

[0188] Specifically, as shown in Figures 4 and 5, the second wiring layer includes a wiring 11 and a wiring 12. As shown in Figure 5, the wiring 12 and the first connection pad 2 have an integral structure, and in Figure 5, the wiring 12 and the first connection pad 2 are distinguished from each other by dotted lines.

[0189] The specific connection manner of the above-mentioned multiple first pad sets is not limited. FIG. 4 shows an example in which two adjacent first pad sets are connected in series. As shown in FIG. 4 and FIG. 5, the multiple first connection pads 2 can be divided into multiple first connection pad sets. Each first connection pad set is used to bind one micro light-emitting diode and includes a cathode pad and an anode pad provided as a pair. The first wiring layer 4 can include an anode wiring 44 and a cathode wiring 45. Two adjacent sets of first connection pads are connected in series through a wiring 11. As shown in FIG. 4 and FIG. 5, among the two first connection pad sets connected in series, one set of anode pads is connected to one wiring 12, and the wiring 12 is electrically connected to the anode wiring 44 through a via hole V1 penetrating the first passivation layer 51 and the first flat layer 61. The anode wiring 44 is electrically connected to one second connection pad 3 through a via hole penetrating the first passivation layer 51 and the first flat layer 61. The other set of cathode pads is connected to another wiring 12, which is connected to a cathode wiring 45 through another via hole V1 penetrating the first passivation layer 51 and the first flat layer 61, and the cathode wiring 45 is electrically connected to another second connection pad 3 through a via hole penetrating the first passivation layer 51 and the first flat layer 61. In Fig. 4, the cathode pad, the anode pad, the second connection pad 3, the wiring 11 and the wiring 12 are provided in the same layer, and the same filling pattern is used to represent the cathode pad, the anode pad, the second connection pad 3, the wiring 11 and the wiring 12. The anode wiring 44 and the cathode wiring 45 are provided in the same layer, and the same filling pattern is used to represent the anode wiring 44 and the cathode wiring 45.

[0190] It is understood that the present disclosure does not limit the driving method of the functional backplane, and as shown in FIG. 4, the functional backplane can drive the light-emitting units using a passive method, or can provide signals to the light-emitting units through a driving circuit including a thin film transistor, or can provide signals to the light-emitting units through a microchip.

[0191] Specifically, when providing a signal to the light-emitting unit through the microchip, each microchip includes a plurality of pins. The wiring board further includes a third connection pad located in the device region, and the third connection pad is used to bind and connect with the pin of the microchip. The structure of the third connection pad is similar to that of the first connection pad, and can be fabricated using the same film layer structure as that of the first connection pad. The plurality of electronic components can be divided into a plurality of lamp regions, each lamp region includes at least one electronic component, and each microchip is used to drive the electronic component of at least one lamp region to emit light.

[0192] In some embodiments, the above functional backplane provided by the embodiments of the present invention further includes a protective layer 8, as shown in Figures 5 and 6. The protective layer 8 is located on one side of the second wiring layer. The protective layer 8 exposes the first connection pads 2. The material of the protective layer 8 can include silicon oxynitride, silicon nitride, and silicon oxide.

[0193] In some embodiments, as shown in Figures 7A to 7C, in a functional backplane, the multiple electronic components include at least one first electronic component. At a first connection pad 2 to be welded to a pin 30 included in the at least one first electronic component, a groove W is formed in a surface of a first reference protective layer 212A included in a first electrical connection layer 21A that faces away from the base substrate 1. A second solder X2 is provided in the groove W. The second solder X2 forms a first intermetallic compound IMC1 with at least a sidewall of the groove W.

[0194] In these embodiments, the first reference protective layer 212A included in the first electrical connection layer 21A is the protective layer 212 that is farthest from the base substrate 1 in the first connection pad 2. In this case, different situations may exist depending on whether the electrical connection layer 21 has one layer or multiple layers and whether the bottom of the groove W is in direct contact with the body material layer 211 or the protective layer 212.

[0195] Here, taking as an example a case where the number of layers of the electrical connection layer 21 is only two and each electrical connection layer 21 includes one main body material layer 211 and one protective layer 212 (i.e., the first reference protective layer 212A included in the above-mentioned first electrical connection layer 21A and the first reference protective layer 212A included in the second electrical connection layer 21B), it will be explained that the second solder X2 forms a first intermetallic compound IMC1 with at least the side wall of the groove W.

[0196] In the first situation, as shown in FIG. 7A, the material of the protective layer 212 included in the two electrical connection layers 21 is selected from materials that can form a first intermetallic compound with the first solder. After the first welding, the first solder forms a first intermetallic compound with the protective layer 212A included in the electrical connection layer 21 (i.e., the first electrical connection layer 21A) that is farthest from the base substrate 1. The thickness of the first intermetallic compound is smaller than the thickness of the protective layer 212A included in the upper electrical connection layer 21. When the electronic component is incompletely welded or misaligned, the first intermetallic compound is also removed at the same time as removing the electronic component. At this time, the surface of the protective layer 212A included in the electrical connection layer 21A that is farther from the base substrate 1 forms a groove W, and the protective layer 212A included in the electrical connection layer 21A still remains, that is, the sidewall and bottom of the groove W are both the protective layer 212A. At this time, by providing a second solder X2 in the groove W, the second solder X2 continues to form a first intermetallic compound IMC1-1 with both the sidewall and bottom of the groove W (i.e., the protective layer 212A), and the pin 30 of a new electronic component is welded to the first connection pad 2, thereby achieving repair.

[0197] In the second situation, as shown in FIG. 7B, the materials of the protective layers 212 (i.e., the first reference protective layer 212A included in the first electrical connection layer 21A and the first reference protective layer 212A included in the second electrical connection layer 21B) included in the two electrical connection layers 21 can both form a first intermetallic compound with the first solder. After the first welding, the first solder X1 forms a first intermetallic compound with the protective layer 212A included in the electrical connection layer 21A that is farthest from the base substrate 1, and also forms a first intermetallic compound with the main body material layer 211 included in the upper electrical connection layer 21. The thickness of the first intermetallic compound formed by the first solder and the main body material layer 211 included in the upper electrical connection layer 21 is thinner than the thickness of the main body material layer 211. When the electronic component is incompletely welded or misaligned, after removing the electronic component, a groove W is formed on the surface of the protective layer 212A and the body material layer 211 included in the electrical connection layer 21A that is away from the base substrate 1, the bottom of the groove W is the body material layer 211, and the sidewall of the groove W includes both the reserved protective layer 212 and the reserved body material layer 211. At this time, by providing a second solder X2 in the groove W, the second solder X2 continues to react with the sidewall (i.e., the protective layer 212A included in the electrical connection layer 21A) and the bottom (i.e., the body material layer 211 included in the electrical connection layer 21A) of the groove W to form the first intermetallic compound IMC1-1 and the first intermetallic compound IMC1-2, respectively, and the pin 30 of a new electronic component is welded to the first connection pad 2, thereby realizing the repair.

[0198] In the third situation, as shown in FIG. 7C , in the two-layer electrical connection layer 21, the material of the protective layer included in the upper electrical connection layer 21A (i.e., the first reference protective layer included in the above-mentioned first electrical connection layer 21A) can form a first intermetallic compound with the first solder, and the material of the protective layer 212 included in the lower electrical connection layer 21 (i.e., the material of the first reference protective layer 212A included in the second electrical connection layer 21B) cannot form a first intermetallic compound with the first solder, and may be, for example, a molybdenum-niobium alloy. After the first welding, the first solder forms a first intermetallic compound with both the protective layer and the body material layer 211 included in the upper electrical connection layer 21, and the thickness of the first intermetallic compound is The thickness of the protective layer included in the upper electrical connection layer 21 and the thickness of the main body material layer 211 included in the upper electrical connection layer 21 is equal to the sum of the thickness of the protective layer included in the upper electrical connection layer 21 and the thickness of the main body material layer 211 included in the upper electrical connection layer 21. When incomplete welding or misalignment occurs in an electronic component, if the protective layer included in the upper electrical connection layer 21 is completely removed after removing the electronic component and the bottom of the groove W is the lower electrical connection layer 21, the side wall of the groove W is the reserved main body material layer 211. By providing the second solder X2 in the groove W, the second solder X2 continues to form a first intermetallic compound IMC1-2 with the side wall of the groove W (i.e., the portion in the main body material layer 211 included in the upper electrical connection layer 21), and a pin 30 of a new electronic component is welded to the first connection pad 2, thereby realizing repair.

[0199] In these embodiments, in the first connection pad 2 welded to the pin 30 included in at least one first electronic component 20A, a groove W is formed on the surface of the first reference protective layer 212A included in the first electrical connection layer 21A that is away from the base substrate. This groove W is formed by removing the first intermetallic compound in the first connection pad 2. Specifically, by selecting the thickness and material of the protective layer 212 included in the above-mentioned electrical connection layer 21, if a welding defect occurs and the electronic component is removed, the groove W can be formed on the surface of the first reference protective layer 212A included in the first electrical connection layer 21A that is away from the base substrate 1, and at least the part that retains the side wall of the groove W is made of a material that can form the first intermetallic compound IMC1 with the first solder. Therefore, at the time of repair, at least the side wall of the groove W and the first intermetallic compound IMC1 may be formed using the second solder X2. Here, the material of the second solder X2 may be the same as the material of the first solder, and for example, both include an alloy in which the base material is tin, for example, a tin-silver-copper alloy. Alternatively, the second solder X2 may be a material capable of forming a first intermetallic compound IMC1 together with the first reference protective layer 212A and the body material layer 211 included in the first electrical connection layer 2A.

[0200] 7A to 7C, in some embodiments, the at least one electrical connection layer 21 further includes a third electrical connection layer 21C. The third electrical connection layer 21C is the electrical connection layer 21 that is closest to the base substrate 1 among the at least one electrical connection layer 21. A portion of the first connection pad 2 located on one side of the bottom of the groove W includes at least a portion of the first connection pad 2 that is included in the third electrical connection layer 21C. The portion that is included in the third electrical connection layer 21C includes at least a portion of the body material layer 211 that is included in the third electrical connection layer 21C.

[0201] Here, when the electrical connection layer 21 is a single layer, the third electrical connection layer 21C is the above-mentioned first electrical connection layer 21A, and when the electrical connection layer 21 is a two-layer structure, the third electrical connection layer 21C is the above-mentioned second electrical connection layer 21B.

[0202] In these embodiments, the portion located on one side of the bottom of the groove W of the first connection pad 2 that is included in the third electrical connection layer 21C means that after repair, at least the portion of the body material layer 211 included in the third electrical connection layer 21C in the first connection pad 2 is retained, and the bottommost body material layer 211 in the first connection pad 2 is not completely removed, thereby avoiding a situation in which only the above-mentioned adhesive layer is retained and the material of the adhesive layer cannot form a first intermetallic compound with the first solder, resulting in a repair failure.

[0203] Some embodiments of the present disclosure provide a method for manufacturing a functional backplane. Referring to FIG. 8, the method for manufacturing a functional backplane includes S1) to S2).

[0204] S1) A wiring board 10 is prepared. The wiring board 10 includes a base substrate 1 and a plurality of first connection pads 2. The base substrate 1 has a device region A, and the plurality of first connection pads 2 are located within the device region A. The plurality of first connection pads 2 include at least one electrical connection layer 21. Each electrical connection layer 21 includes a body material layer 211 and at least one protective layer 212. The at least one protective layer 212 is located on the side of the body material layer 211 that is away from the base substrate 1. The at least one protective layer 212 includes a first reference protective layer 212A, which is the protective layer 212 that is farthest from the base substrate 1 among the at least one protective layer. The material of the body material layer 211 includes copper. The at least one electrical connection layer 21 includes a first electrical connection layer 21A, which is the electrical connection layer 21 that is farthest from the base substrate 1 among the at least one electrical connection layer 21. In the at least one protective layer 212 included in the first electrical connection layer 21A, the material of at least the first reference protective layer 212A can form a first intermetallic compound with the first solder.

[0205] The method for producing the above wiring board is as follows.

[0206] Step 1) Form a first sub-metal layer 41 and a first sub-wiring layer 42 on a base substrate 1. The material of the first sub-metal layer 41 and the second sub-metal layer 43 may be a molybdenum-containing alloy, which has adhesiveness and oxidation resistance, and can be fabricated by a sputtering method, and the thickness thereof is in the range of several hundred angstroms to several thousand angstroms. The material of the first sub-wiring layer 42 may be copper. The thickness of the first sub-wiring layer 42 may be 1 μm to 5 μm, and can be formed by a sputtering or electroplating process.

[0207] Of course, the first metal sub-layer 41, the first wiring sub-layer 42 and the second metal sub-layer 43 can also be formed by successive deposition and patterning.

[0208] Step 2) Deposit a first passivation layer (SiN) 51 and pattern it to form via holes. The thickness of the first passivation layer 51 is 1000 Å to 4000 Å.

[0209] Step 3) A first flat layer 61 is formed on the base substrate 1 on which the first passivation layer 51 is formed, and a via hole is formed by patterning.

[0210] Step 4) Form an adhesive layer 7, a second wiring layer, and at least one electrical connection layer. Each electrical connection layer 21 includes a body material layer 211 and at least one protective layer 212. The at least one electrical connection layer 21 includes a first electrical connection layer 21A, and the at least one protective layer 212 includes a first reference protective layer 212A. The first reference protective layer 212A is the protective layer 212 farthest from the base substrate 1 among the at least one protective layer 212. The material of the first reference protective layer 212A included in the first electrical connection layer 21A can form a first intermetallic compound with the first solder. The material of the body material layer 211 includes metallic copper. The adhesive layer 7 is electrically connected to the second sub-metal layer 43 through the via holes in the first passivation layer 51 and the first flat layer 61 described above.

[0211] Step 5) Deposit and pattern the second passivation layer 52, the second planarization layer 62 and the protective layer 8 to expose the first connection pads 2.

[0212] S2) Providing at least one electronic component 20. Each electronic component 20 includes a pin 30. Welding the at least one electronic component 20 to a first connection pad 2 via the pin 30 and a first solder X1. The first solder X1 forms a first intermetallic compound with at least a first reference protective layer 212A included in the first electrical connection layer 21A. The first solder forms a second intermetallic compound with the pin 30.

[0213] In some embodiments, as shown in FIGS. 8 and 9, welding at least one electronic component 20 to the first connection pad 2 via the pin 30 and the first solder X1 may include:

[0214] A first solder X1 is provided between a pin 30 included in each electronic component 20 and a first connection pad 2, and the first solder X1 is reacted with the first connection pad 2 and the pin 30, respectively, thereby welding at least one electronic component 20 to the first connection pad 2 via the pin 30 and the first solder X1.

[0215] Specifically, the first solder X1 can be reacted with the first connection pad 2 and the pin 30 in a high-temperature state. Specifically, a reflow soldering process may be used. At this time, the first solder X1 can form a first intermetallic compound IMC1 (e.g., IMC1-1) with at least the first reference protective layer 212A in the first electrical connection layer 21A included in the first connection pad 2, and the first solder X1 can form a second intermetallic compound IMC2 with the pin 30, thereby welding the first connection pad 2 and the pin 30.

[0216] Here, after the reaction is completed, the first solder X1 may remain unreacted between the first intermetallic compound IMC1 and the second intermetallic compound IMC2, or the first solder X1 may not remain at all. That is, the first solder X1 completely diffuses into the first connection pad 2 and the pin 30, and forms the first intermetallic compound IMC1 and the second intermetallic compound IMC2 with the first connection pad 2 and the pin 30, respectively.

[0217] In some embodiments, when the at least one electronic component 20 comprises at least one first electronic component, the method of fabrication may further include:

[0218] The method includes the step of detecting a connection state between at least one electronic component 20 and the wiring board 10.

[0219] That is, it is possible to detect whether or not the electrical connection between at least one electronic component 20 and the wiring board 10 is incompletely welded, or whether or not at least one electronic component 20 is misaligned.

[0220] If the connection state between the second electronic component and the wiring board 10 does not satisfy the requirements, the second electronic component is replaced with the first electronic component.

[0221] When the connection state between the second electronic component and the wiring board 10 does not satisfy the requirements, it means that there is incomplete welding between the second electronic component and the wiring board 10, or the second electronic component is misaligned. In this case, the second electronic component is replaced, that is, the second electronic component is repaired.

[0222] In some embodiments, as shown in FIG. 10, exchanging the second electronic component and replacing the second electronic component with the first electronic component includes the following steps.

[0223] S21) The second electronic component 20B is removed, and a groove W is formed on the surface of the first connection pad 2 that faces away from the base substrate 1.

[0224] For example, the second electronic component 20B can be removed by applying a lateral shear force to the second electronic component 20B. In this process, the portion of the first connection pad 2 that forms the first intermetallic compound IMC1 (e.g., IMC1-1) with the first solder X1 is also removed, so that a groove W is formed on the surface of the first connection pad 2 that faces away from the base substrate 1.

[0225] S22) A second solder X2 is provided in the groove W. The pin 30 included in the first electronic component 20A is welded to the first connection pad 2 by the second solder X2. The second solder X2 forms a first intermetallic compound IMC1 with at least the side wall of the groove W.

[0226] Here, depending on whether the bottom of the groove W is in direct contact with the body material layer 211 or in direct contact with the protective layer 212, and whether the bottom of W can form a first intermetallic compound IMC1 with the second solder X2, the second solder X2 can form a first intermetallic compound IMC1 with the sidewall of the groove W, or the second solder X2 can form a first intermetallic compound IMC1 with both the sidewall and the bottom of the groove W. Specifically, the above description of the electrical connection layer 21 having two layers and the second solder X2 forming a first intermetallic compound IMC1 with at least the sidewall of the groove W can be referred to, and will not be repeated here.

[0227] The above are merely specific embodiments of the present disclosure, and the scope of protection of the present disclosure is not limited thereto, and any modifications or replacements that can be easily conceived by a person skilled in the art within the technical scope of the present disclosure are all included within the technical scope of the present disclosure. Therefore, the scope of protection of the present disclosure shall be governed by the scope described in the claims.

Claims

1. A base substrate; A plurality of first connection pads provided on the base substrate; Including, The plurality of first connection pads include at least one electrical connection layer, each of the electrical connection layers includes a body material layer and at least one protective layer, the at least one protective layer is provided on a side of the body material layer away from the base substrate, the at least one protective layer includes a first reference protective layer, the first reference protective layer is the protective layer farthest from the base substrate among the at least one protective layer, and the material of the body material layer includes copper; the at least one electrical connection layer includes a first electrical connection layer, the first electrical connection layer being an electrical connection layer farthest from the base substrate among the at least one electrical connection layer, and in the at least one protective layer included in the first electrical connection layer, a material of at least the first reference protective layer can form a first intermetallic compound with a first solder; Wiring board.

2. the material of the first reference protective layer included in the first electrical connection layer is a metal or a metal alloy; and / or The thickness of each protective layer included in the first electrical connection layer is 300 Å or more and 30,000 Å or less. The wiring board according to claim 1 .

3. a thickness or material of the at least one protective layer included in the first electrical connection layer is configured to block diffusion of the first solder into the body material layer included in the first electrical connection layer; The wiring board according to claim 1 .

4. When the material of the first reference protective layer included in the first electrical connection layer includes copper or a copper-nickel alloy, the thickness of the first reference protective layer is between 300 Å and 600 Å; When the material of the first reference protective layer included in the first electrical connection layer does not include copper, the thickness of the first reference protective layer is between 300 Å and 3000 Å; or When the material of the first reference protective layer included in the first electrical connection layer includes copper or a copper-nickel alloy, the thickness of the first reference protective layer is between 300 Å and 600 Å; When the material of the first reference protective layer included in the first electrical connection layer does not include copper, the thickness of the first reference protective layer is between 300 Å and 3000 Å, and the diffusion depth of the first solder in the at least one protective layer is equal to or greater than the thickness of the first reference protective layer included in the first electrical connection layer. The wiring board according to claim 3 .

5. The at least one protective layer includes at least two protective layers, the at least two protective layers further include the first reference protective layer and a second reference protective layer, the second reference protective layer is located between the first reference protective layer and the base substrate, and a material of the second reference protective layer can form a first intermetallic compound with the first solder or a material of the second reference protective layer cannot form a first intermetallic compound with the first solder. The wiring board according to claim 1 .

6. the material of the second reference protective layer is capable of forming a first intermetallic compound with the first solder; The materials of the at least two protective layers are different, or the thickness of at least one of the at least two protective layers is greater than 500 Å, or the sum of the thicknesses of the at least two protective layers is greater than 500 Å; The wiring board according to claim 5 .

7. Along a direction gradually approaching the base substrate, the diffusion depth of the first solder in the at least two protective layers per unit time gradually decreases, and / or the melting point of the material of the at least two protective layers gradually increases, and / or and / or the proportion of elements capable of forming a first intermetallic compound with the first solder in the at least two protective layers gradually decreases along a direction gradually approaching the base substrate; the thickness of the at least two protective layers gradually increases along a direction gradually approaching the base substrate; and / or a diffusion depth of the first solder in the at least one protective layer is equal to or greater than a thickness of the first reference protective layer and is equal to or less than a sum of a thickness of the first reference protective layer and a thickness of the second reference protective layer; The wiring board according to claim 6 .

8. The at least one electrical connection layer further includes a second electrical connection layer, the second electrical connection layer being located between the first electrical connection layer and the base substrate, and a material of the first reference protective layer included in the second electrical connection layer can form a first intermetallic compound with a first solder, or a material of the first reference protective layer included in the second electrical connection layer cannot form a first intermetallic compound with the first solder. The wiring board according to claim 1 .

9. The thickness of the first reference protective layer included in the second electrical connection layer is 300 Å or more and 30,000 Å or less, and / or a material of the first reference protective layer included in the second electrical connection layer is capable of forming a first intermetallic compound with a first solder, and a thickness of the first reference protective layer included in the second electrical connection layer is greater than a thickness of the first reference protective layer included in the first electrical connection layer; and / or a diffusion depth of the first solder in the at least one electrical connection layer is equal to or greater than a thickness of a first reference protective layer included in the first electrical connection layer, and is equal to or less than a sum of a thickness of the first electrical connection layer and a thickness of a first reference protective layer included in the second electrical connection layer; The wiring board according to claim 8 .

10. and further comprising a plurality of second connection pads provided on the base substrate, the second connection pads being configured to be electrically connected to a circuit board. The wiring board according to claim 1 .

11. The wiring board according to any one of claims 1 to 10 and a first solder, at least one electronic component, each electronic component including a pin, the electronic component being welded to the first connection pad via the pin and the first solder; Including, The first solder forms a first intermetallic compound with at least the first reference protective layer included in the first electrical connection layer. Functional backplane.

12. The at least one electronic component includes at least one first electronic component, and in a first connection pad to be welded to a pin included in the at least one first electronic component, a groove is formed on a surface of the first reference protective layer included in the at least one first electrical connection layer that faces away from the base substrate, and a second solder is provided in the groove, and the second solder forms a first intermetallic compound with at least a side wall of the groove, or The at least one electrical connection layer further includes a third electrical connection layer, the third electrical connection layer being the electrical connection layer closest to the base substrate among the at least one electrical connection layer; a portion of the first connection pad located on one side of a bottom of the groove includes at least a portion of the first connection pad included in the third electrical connection layer, and the portion included in the third electrical connection layer includes at least a portion of a body material layer included in the third electrical connection layer; The functional backplane of claim 11.

13. a step of manufacturing a wiring board, the wiring board including a base substrate and a plurality of first connection pads, the plurality of first connection pads being disposed on the base substrate, the plurality of first connection pads including at least one electrical connection layer, each of the electrical connection layers including a body material layer and at least one protective layer, the at least one protective layer being disposed on a side of the body material layer away from the base substrate, the at least one protective layer including a first reference protective layer, the first reference protective layer being the protective layer farthest from the base substrate among the at least one protective layer, a material of the body material layer including copper, the at least one electrical connection layer including a first electrical connection layer, the first electrical connection layer being the electrical connection layer farthest from the base substrate among the at least one electrical connection layer, and in the at least one protective layer included in the first electrical connection layer, a material of at least the first reference protective layer is capable of forming a first intermetallic compound with a first solder; providing at least one electronic component, each electronic component including a pin; welding the electronic component to the first connection pad via the pin and the first solder, the first solder forming a first intermetallic compound with at least the first reference protective layer included in the first electrical connection layer, and the first solder forming a second intermetallic compound with the pin; Including, How to create a functional backplane.

14. The step of welding the electronic component to the first connection pad via the pin and the first solder includes: providing a first solder between a pin included in each electronic component and the first connection pad, reacting the first solder with the first connection pad and the pin, respectively, and welding the at least one electronic component to the first connection pad via the pin and the first solder; A method for making the functional backplane of claim 13.

15. When the at least one electronic component includes a plurality of electronic components, and the plurality of electronic components includes at least one first electronic component, the method further includes: detecting a connection state between the plurality of electronic components and the first connection pad; if a connection state between the second electronic component and the first connection pad does not satisfy a requirement, replacing the second electronic component with the first electronic component; or When the at least one electronic component includes a plurality of electronic components, and the plurality of electronic components includes at least one first electronic component, the manufacturing method further includes a step of detecting a connection state between the plurality of electronic components and the first connection pad, and when a connection state between a second electronic component and the first connection pad does not satisfy a requirement, the step of replacing the second electronic component and replacing the second electronic component with the first electronic component includes a step of removing the second electronic component and forming a groove on a surface of the first connection pad away from the base substrate, providing a second solder in the groove, and welding a pin included in the first electronic component to the first connection pad via the second solder, the second solder forming the first intermetallic compound with at least a side wall of the groove, The step of exchanging the second electronic component and replacing the second electronic component with the first electronic component includes: removing the second electronic component and forming a groove on a surface of the first connection pad that faces away from the base substrate; providing a second solder in the groove, and welding a pin included in the first electronic component to the first connection pad via the second solder, the second solder forming the first intermetallic compound with at least a sidewall of the groove; Including, A method for making the functional backplane of claim 13.

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