Silver alloy bonding wire, its preparation method and use

Abstract

To provide a silver alloy bonding wire that has excellent dynamic characteristics and corrosion resistance.SOLUTION: The present invention belongs to the technical field of a material for packaging, and relates particularly to a silver alloy bonding wire, and an adjustment method and use thereof. The silver alloy bonding wire according to the present invention includes a core material, and the core material includes 0.5 wt.%-0.7 wt.% of Al, 0.6 wt.%-1 wt.% of Ce, 1 wt.%-3 wt.% of carbon nano-tube, and 0.3 wt.%-0.5 wt.% of Sb, and the remainder is Ag. The silver alloy bonding wire according to the present invention improves the dynamic characteristics, processing performance, corrosion resistance, and electromigration resistance of the silver alloy bonding wire through cooperation of elements, and when used for electronic packaging, can satisfy packaging requirements for an LED device with fine wire diameter processing and a high-density lead.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to the technical field of packaging materials, and in particular to a silver alloy bonding wire, its preparation method and use. [Background technology]

[0002] Wire bonding is the most common and most important interconnection method for microelectronic packages. Bonding wire is the inner lead for packaging, and is used as a welding lead between the chip and the frame, connecting pins and silicon wafers, and transmitting electrical signals. It electrically connects the chip to external circuits. It is one of the basic raw materials essential for the repackaging manufacturing process of integrated circuits, semiconductor discrete devices, and LED light source devices. Bonding wire mainly includes gold wire, silver wire, aluminum wire, copper wire, etc. Silver wire has good mechanical properties, can reduce high-frequency noise and heat generation in devices, and has a significant price advantage over gold wire. Summary of the Invention [Problem to be solved by the invention]

[0003] As semiconductor packaging becomes increasingly dense and integrated, bonding reliability is becoming more important. However, silver wires have problems such as low bond strength, electromigration, and metal corrosion and sulfidation, which reduce reliability and significantly limit their applications. In view of this, the present invention has been devised.

[0004] A first object of the present invention is to provide a silver alloy bonding wire having excellent mechanical properties and corrosion resistance.

[0005] A second object of the present invention is to provide a method for preparing a silver alloy bonding wire that can improve the mechanical properties and corrosion resistance of the bonding wire.

[0006] A third object of the present invention is to provide a silver alloy bonding wire for use in electronic packaging, which can improve bonding reliability.

[0007] In order to achieve the above object of the present invention, the following technical solutions are particularly adopted. [Means for solving the problem]

[0008] The present invention provides a silver alloy bonding wire, which includes a core material containing, by mass fraction, 0.5 wt% to 0.7 wt% Al, 0.6 wt% to 1 wt% Ce, 1 wt% to 3 wt% carbon nanotubes, 0.3 wt% to 0.5 wt% Sb, and the remainder being Ag.

[0009] Furthermore, in the core material, the sum of the mass fractions of the Al and the Sb is 1%, and / or the sum of the mass fractions of the Al, the Ce, the carbon nanotubes, and the Sb in the core material is 3.5% or less.

[0010] Furthermore, the carbon nanotubes include single-walled carbon nanotubes, and / or the carbon nanotubes have a diameter of 2 nm or less and a length of 50 nm or less.

[0011] Furthermore, it further includes a protective layer formed on the surface of the core material, and / or the protective layer formed on the surface of the core material contains, by weight, 3 to 5 parts of film-forming agent, 1 to 3 parts of surfactant, and 1 to 3 parts of solubilizing agent.

[0012] Furthermore, the film-forming agent includes at least one of ethylene glycol monovinyl ether, polyacrylate, and polyvinyl acetate, the surfactant includes at least one of polyethylene glycol fatty acid ester, sodium dodecyl sulfate, and sodium dodecylbenzenesulfonate, and the solubilizing agent includes at least one of para-aminobenzoic acid, acetone, and methanol.

[0013] Furthermore, the diameter of the core material is 15 to 40 μm, and / or the thickness of the protective layer is 1.5 to 4 μm.

[0014] The present invention further provides a method for preparing the silver alloy bonding wire, which includes step S1 of melting and pouring an Ag / Ce intermediate alloy, an Sb raw material, an Al foil, and the carbon nanotubes to obtain a rod, and step S2 of extruding and drawing the rod to obtain the core material.

[0015] Furthermore, in step S2, the extrusion temperature is 700 to 750°C, and / or the extrusion ratio is 3 to 4.5.

[0016] Furthermore, the method for preparing the silver alloy bonding wire includes at least one of the following: (1) further comprising the steps of sequentially performing cleaning, annealing, and immersion treatment on the core material to obtain the silver alloy bonding wire; (2) the temperature of the annealing treatment is 450 to 500°C; and (3) the immersion treatment includes immersing the core material after the annealing treatment in a protective agent to obtain a protective layer, and the protective agent includes, by weight, 3 to 5 parts of film-forming agent, 1 to 3 parts of surfactant, 1 to 3 parts of dissolution aid, and 70 to 80 parts of solvent.

[0017] The present invention further provides the use of the above silver alloy bonding wire or the silver alloy bonding wire prepared by the above method for preparing a silver alloy bonding wire in electronic packaging.

[0018] Compared with the prior art, the present invention has the following beneficial effects: 1. The silver alloy bonding wire of the present invention is made by adding Sb and carbon nanotubes to the silver alloy, and by cooperating with Ce and Al, the mechanical properties, processing performance, electromigration resistance and corrosion resistance of the silver alloy bonding wire are improved, and the requirements for fine wire diameter processing and high-density lead packaging for LED devices can be met. 2. The silver alloy bonding wire according to the present invention has a protective layer on the surface of the core material, which further improves the corrosion resistance of the silver alloy bonding wire and prevents sulfurization and corrosion of the core material. 3. The method for preparing the silver alloy bonding wire according to the present invention can increase the density and strength of the silver alloy bonding wire through processes such as melting, pouring and extrusion. [Brief explanation of the drawings]

[0019] In order to more clearly describe the specific embodiments of the present invention or the technical solutions in the prior art, the drawings used in the specific embodiments or the prior art will be briefly described below. The drawings described only show some embodiments of the present invention. Those skilled in the art can obtain other drawings based on these drawings without using inventive ability. [Figure 1] 1 is a graph showing the corrosion resistance of silver alloy bonding wires 1# to 11# according to Example 1 of the present invention and Comparative Example 1. DETAILED DESCRIPTION OF THE INVENTION

[0020] The following provides a clear and complete description of the technical solutions of the present invention with the aid of drawings and specific embodiments. Those skilled in the art will appreciate that the described examples are only some of the examples of the present invention, not all of the examples, and are merely illustrative of the present invention and do not limit the scope of the present invention. Based on the examples of the present invention, all other examples obtained by those skilled in the art without using their inventive abilities also fall within the scope of protection of the present invention. In the examples, specific conditions are not specified, but they can be carried out under conventional conditions or under conditions recommended by the manufacturer. For reagents or equipment whose manufacturers are not specified, conventional products available on the market can be used.

[0021] The term "and / or" as used herein represents a relationship between related objects and represents a three-way relationship, such as A and / or B, where only A is present, both A and B are present, or only B is present.

[0022] Some embodiments of the present invention provide a silver alloy bonding wire, which includes a core material containing, by mass fraction, 0.5 wt% to 0.7 wt% Al, 0.6 wt% to 1 wt% Ce, 1 wt% to 3 wt% carbon nanotubes, 0.3 wt% to 0.5 wt% Sb, and the remainder being Ag.

[0023] The silver alloy bonding wire of the present invention can solve the problems associated with silver wire, such as low connection strength, susceptibility to electromigration, metal corrosion and sulfurization, etc. The silver alloy bonding wire of the present invention has excellent mechanical properties, processability, electromigration resistance, sulfurization resistance, and corrosion resistance, and can meet the requirements for fine wire diameter processing and high-density lead packaging for LED devices.

[0024] In the silver alloy bonding wire according to the present invention, by adding Al element, a dense protective layer is formed on the surface of the silver, passivating the surface and improving the corrosion resistance of the silver alloy wire; by adding Ce element, corrosion resistance can be improved, the growth rate and diffusion rate of IMC at the Ag / Al interface can be increased, and bonding reliability can be improved; by improving carbon nanotubes, thermal conductivity can be increased and electron mobility can be reduced, and the carbon nanotubes, as a nano-reinforcement phase, promote the increase of nucleation sites in the non-spontaneous nucleation of silver metal liquid, thereby refining the crystal grains and increasing the strength of the bonding wire; by adding Sb element, Sb element is deposited at the crystal grain boundaries, thereby reducing the diffusion along the crystal grain boundaries and improving strength and electromigration resistance.

[0025] In some embodiments of the present invention, as a representative and non-limiting example, in the core material, the mass fraction of Al is 0.5 wt%, 0.55 wt%, 0.6 wt%, 0.65 wt%, 0.7 wt%, or a value within a range consisting of any two values ​​thereof, and the mass fraction of Ce is 0.6 wt%, 0.65 wt%, 0.7 wt%, 0.75 wt%, 0.8 wt%, 0.85 wt%, 0.9 wt%, 0.95 wt%, 1 wt%, or any two values ​​thereof. the mass fraction of carbon nanotubes is 1 wt%, 1.2 wt%, 1.4 wt%, 1.6 wt%, 1.8 wt%, 2 wt%, 2.2 wt%, 2.4 wt%, 2.6 wt%, 2.8 wt%, 3 wt%, or a value within a range consisting of any two values ​​thereof; and the mass fraction of Sb is 0.3 wt%, 0.35 wt%, 0.4 wt%, 0.45 wt%, 0.5 wt%, or a value within a range consisting of any two values ​​thereof.

[0026] The present invention further optimizes the composition of the core material in the silver alloy bonding wire in order to improve the mechanical properties and corrosion resistance of the silver alloy bonding wire.

[0027] In some embodiments of the present invention, the core material contains, by mass fraction, 0.55 wt% to 0.65 wt% Al, 0.75 wt% to 0.85 wt% Ce, 1.1 wt% to 1.3 wt% carbon nanotubes, 0.3 wt% to 0.5 wt% Sb, and the remainder is Ag.

[0028] In some embodiments of the present invention, the total mass fraction of Al and Sb in the core material is 1%.

[0029] In some embodiments of the present invention, the total mass fraction of Al, Ce, carbon nanotubes, and Sb in the core material is 3.5% or less.

[0030] In some embodiments of the present invention, the carbon nanotubes comprise single-walled carbon nanotubes.

[0031] In some embodiments of the present invention, the carbon nanotubes have a diameter of 2 nm or less and a length of 50 nm or less.

[0032] The carbon nanotubes of the above sizes can be distributed uniformly in the alloy. When the bonding wire is drawn to a very thin state, the carbon nanotubes are relatively large in size, which is unfavorable for deformation and drawing of the alloy and results in poor mechanical properties.

[0033] In some embodiments of the present invention, the bonding wire further includes a protective layer provided on the surface of the core material.

[0034] In some embodiments of the present invention, the protective layer comprises, by weight, 3 to 5 parts of a film-forming agent, 1 to 3 parts of a surfactant, and 1 to 3 parts of a solubilizing agent.

[0035] In some embodiments of the present invention, the film-forming agent includes, but is not limited to, at least one of ethylene glycol monovinyl ether, polyacrylate, and polyvinyl acetate.

[0036] In some embodiments of the present invention, the surfactant includes, but is not limited to, at least one of polyethylene glycol fatty acid esters, sodium dodecyl sulfate, and sodium dodecylbenzene sulfonate.

[0037] In some embodiments of the present invention, the solubilizing agent includes, but is not limited to, at least one of para-aminobenzoic acid, acetone, and methanol. Para-aminobenzoic acid can remove dirt, oil, etc., and prevent corrosion.

[0038] The protective layer according to the present invention can prevent sulfurization and corrosion of the core material of the silver alloy bonding wire, and does not affect the bonding process of the silver alloy bonding wire.

[0039] In some embodiments of the present invention, the protective layer contains, by weight, 3 to 5 parts of ethylene glycol monovinyl ether, 1 to 3 parts of polyethylene glycol fatty acid ester, and 1 to 3 parts of para-aminobenzoic acid.

[0040] In some embodiments of the present invention, the diameter of the core material is 15 to 40 μm, and representatively and non-limitingly, for example, 15 μm, 20 μm, 25 μm, 30 μm, 35 μm, 40 μm, or a value within a range consisting of any two values ​​therein, and the thickness of the protective layer is 1.5 to 4 μm, and representatively and non-limitingly, for example, 1.5 μm, 2 μm, 2.5 μm, 3 μm, 3.5 μm, 4 μm, or a value within a range consisting of any two values ​​therein.

[0041] In some embodiments of the present invention, the tensile breaking strength of the silver alloy bonding wire is 9 to 10 g.

[0042] In some embodiments of the present invention, the elongation of the silver alloy bonding wire is 9% to 12%, and preferably 10.5% to 12%.

[0043] Some embodiments of the present invention further provide a method for preparing the above silver alloy bonding wire, the method comprising the steps of:

[0044] Step S1: The Ag / Ce intermediate alloy, the Sb raw material, the Al foil, and the carbon nanotubes are melted and poured in this order to obtain a rod.

[0045] Step S2: The rod material is extruded and drawn in order to obtain a core material.

[0046] The method for preparing a silver alloy bonding wire according to the present invention can increase the density and strength of the silver alloy bonding wire through processes such as melting, pouring, and extrusion.

[0047] In some embodiments of the present invention, the method for preparing the Ag / Ce intermediate alloy in step S1 includes:

[0048] The Ag raw material and the Ce raw material were weighed according to the mixing ratio and placed in a crucible in a vacuum furnace. The furnace door was closed and a 3×10 -2 The mixture is evacuated to 600 to 800°C, argon gas is introduced until the pressure reaches 0.1 to 0.3 Pa, and the temperature is raised to 600 to 800°C. The evacuation and argon gas introduction operations are repeated three times, and the mixture is then heated to 1200 to 1250°C, stirred for 3 to 5 minutes, refined for 10 to 15 minutes, degassed, and cooled in the furnace to obtain an Ag / Ce intermediate alloy. Preferably, the purity of each of the Ag raw material and the Ce raw material is greater than 99.99%.

[0049] In some embodiments of the present invention, in step S1, the Ag / Ce intermediate alloy, the Sb raw material, the Al foil, and the carbon nanotubes are placed in a vacuum furnace. -2After evacuating to 0.1 to 0.3 Pa, argon gas is introduced until the pressure reaches 0.1 to 0.3 Pa. The evacuation and argon gas introduction operations are repeated three times, and the temperature is then raised to 1250 to 1300°C, stirred for 15 to 20 minutes using a magnetic stirrer, and when the temperature is lowered to 1150 to 1200°C, the molten metal is poured into a rod having a diameter of 30 to 50 mm.

[0050] In some embodiments of the present invention, the method of adding the Al foil and the carbon nanotubes in step S1 is to place the carbon nanotube powder on the Al foil, and then sandwich and fold the powder between two Al foils.

[0051] In some embodiments of the present invention, the extrusion temperature in step S2 is 700-750°C, and the extrusion ratio of the extrusion is 3-4.5. Preferably, the extrusion includes the following steps: placing the rod in a container of an extruder, heating it to 700-750°C, and holding the temperature for 2 hours; extruding the rod at a speed of 3-4 mm / s, an extrusion ratio of 3-4.5, and a rotation speed of the extrusion wheel of 5-7 r / min; and extruding a rod having a diameter of 5-10 mm.

[0052] The present invention utilizes degassing, refining, and bar pouring, and peeling extrusion of the bar instead of continuous casting, further increasing density and strength.

[0053] In some embodiments of the present invention, the drawing comprises at least two drawing processes, with each drawing process being followed by a heat treatment, and preferably the drawing comprises a first drawing process, a heat treatment, and a second drawing process, in sequence.

[0054] In some embodiments of the present invention, the first wire drawing process in step S2 includes drawing the extruded rod into a wire having a diameter of 0.8 to 1.1 mm using a wire drawing machine, and the extrusion has a reduction rate of 15% to 18% per pass and a wire drawing speed of 1.2 to 1.8 m / s.

[0055] In some embodiments of the present invention, the heat treatment in step S2 includes the following: A wire having a diameter of 0.8 to 1.1 mm is placed in a vacuum annealing furnace; -2 ~5×10 -2 The temperature is raised to 350-400°C at a rate of 2-3.5°C / s in a vacuum of 100 Pa, and the heat treatment is carried out for 3-5 hours, after which the furnace is cooled to 80°C or below.

[0056] In some embodiments of the present invention, the second wiredrawing process in step S2 includes the following: The heat-treated wire is subjected to drawing using a multi-wiredrawing machine, and a core material having a wire diameter of 15 to 40 μm is obtained by drawing a thin wire. Preferably, in the drawing process using the multi-wiredrawing machine, the reduction rate per pass is 10% to 13%, and the drawing speed is 2 to 2.5 m / s. In the drawing process of the thin wire, the diameter reduction rate is 15% to 18%, and the drawing speed is 3 to 5 m / s.

[0057] In some embodiments of the present invention, the method for preparing the silver alloy bonding wire further includes the steps of sequentially performing cleaning, annealing and immersion treatments on the core material to obtain the silver alloy bonding wire.

[0058] In some embodiments of the present invention, the annealing includes the following steps: passing the washed core material through an in-line annealing device equipped with an antioxidant liquid dripping device, at a passing speed of 2.5 to 3 m / s, and at an annealing temperature of 450 to 500°C.

[0059] Annealing can remove the work hardening caused by the previous process, improve the stability and reliability of the bonding wire, and improve the mechanical strength of the bonding wire, allowing the bonding wire to withstand a greater tensile breaking force. The resistivity and conductivity of the bonding wire are deeply dependent on its crystal structure and lattice defects, and annealing can promote the growth of crystal grains and the repair of lattice defects, thereby improving the electrical performance and conductivity of the bonding wire.

[0060] In some embodiments of the present invention, the immersion treatment comprises immersing the annealed core material in a protective agent to obtain a protective layer.

[0061] The protective agent contains, by weight, 3 to 5 parts of film-forming agent, 1 to 3 parts of surfactant, 1 to 3 parts of solubilizing agent, and 70 to 80 parts of solvent.

[0062] In some embodiments of the present invention, the solvent includes, but is not limited to, ethanol.

[0063] In some embodiments of the present invention, the immersion treatment is carried out for a period of 20 to 25 minutes at a temperature of 40 to 50°C.

[0064] In some embodiments of the present invention, cleaning is performed by immersing the core material in deionized water and applying ultrasonic vibration for 5 to 10 minutes to remove surface dirt.

[0065] In some embodiments of the present invention, the method further includes the steps of washing with deionized water after the immersion treatment, subjecting the substrate to ultrasonic vibration for 15 to 20 minutes, drying with nitrogen gas, and winding the substrate on a reel.

[0066] Some embodiments of the present invention further provide for the use of the above silver alloy bonding wire or a silver alloy bonding wire prepared by the above method for preparing a silver alloy bonding wire in electronic packaging.

[0067] Example 1 This example provides a method for preparing a silver alloy bonding wire. The core material components and contents (mass fractions) of the prepared silver alloy bonding wire are shown in Table 1.

[0068] [Table 1]

[0069] Specifically, the method for preparing the above silver alloy bonding wire includes the following steps:

[0070] Step S1: Place Ag raw material with a purity of over 99.99% and Ce raw material with a purity of over 99.9% into the crucible of a vacuum melting furnace, close the furnace door, and -2 The furnace was evacuated to 0.1-0.3 Pa, and argon gas was introduced until the pressure reached 0.1-0.3 Pa. The evacuation and argon gas introduction operations were repeated three times, and then the furnace was heated to 1200-1250°C, stirred for 3-5 minutes, kept at that temperature, refined for 10-15 minutes, degassed, and cooled to room temperature to obtain an Ag / Ce intermediate alloy.

[0071] Step S2: Ag / Ce intermediate alloy, Sb raw material with a purity of 99.99%, and carbon nanotubes (single-walled carbon nanotubes, diameter ≦2 nm, length ≦50 nm) coated with Al foil (the purity of the Al foil is 99.99%, and the carbon nanotube powder was laid on the Al foil, sandwiched between two sheets of Al foil, and folded for addition) were mixed according to the compounding ratio, and the mixture was placed in a vacuum melting furnace. -2 After evacuating to 100 Pa, argon gas was introduced until the pressure reached 0.1 to 0.3 Pa. The evacuation and argon gas introduction operations were repeated three times, and the temperature was then raised to 1250 to 1300°C and stirred for 15 to 20 minutes using a magnetic stirrer. When the temperature was lowered to 1150 to 1200°C, the molten metal was poured into the mold to form rods with a diameter of 30 to 50 mm.

[0072] Step S3: A rod with a diameter of 30-50 mm is placed in the container of the extruder, heated to 700-750°C, and kept at that temperature for 2 hours. After extrusion, the head and tail are separated to obtain a rod with a diameter of 5-10 mm. The extrusion speed of the rod is 3-4 mm / s, the extrusion ratio is 3-4.5, and the rotation speed of the extrusion wheel is 5-7 r / min.

[0073] Step S4: A rod having a diameter of 5 to 10 mm was drawn into a wire having a diameter of 0.8 to 1.1 mm by a wire drawing machine, and the reduction rate per pass was 15% to 18%, and the wire drawing speed was 1.2 to 1.8 m / s.

[0074] Step S5: Put the wire rod with a diameter of 0.8 to 1.1 mm into a vacuum annealing furnace and heat it for 3 × 10 -2 ~5×10 -2 The sample was heated to 350-400°C at a rate of 2-3.5°C / s under a vacuum of 100 Pa, and then heat-treated for 3-5 hours. The sample was then cooled to 80°C or less and removed from the furnace.

[0075] Step S6: The heat-treated wire was drawn using a multi-wire drawing machine to produce a wire with a diameter of 0.1 mm or less, with a reduction rate of 10% to 13% per pass and a drawing speed of 2 to 2.5 m / s.

[0076] Step S7: A wire rod with a diameter of 0.1 mm or less was subjected to thin wire drawing to obtain a core material with a diameter of 15 μm, with a diameter reduction rate of 15% to 18% and a wire drawing speed of 3 to 5 m / s.

[0077] Step S8: The core material was immersed in deionized water and subjected to ultrasonic vibration for 5 to 10 minutes to remove surface dirt.

[0078] Step S9: The washed core material was passed through an in-line annealing device equipped with an anti-oxidation liquid dropping device, the linear velocity was 2.5-3 m / s, and the annealing temperature was 450-500°C.

[0079] Step S10: The annealed core material is immersed in a protective agent at 40-50°C for 20-25 minutes, then rinsed with deionized water, subjected to ultrasonic vibration for 15-20 minutes, dried with nitrogen gas, and wound onto a reel to obtain a silver alloy bonding wire. The protective agent contains, by weight, 4 parts ethylene glycol monovinyl ether, 2 parts polyethylene glycol fatty acid ester, 2 parts para-aminobenzoic acid, and 75 parts ethanol.

[0080] <Comparative Example 1> This comparative example provides a method for preparing a silver alloy bonding wire. The core material components and contents (mass fractions) of the prepared silver alloy bonding wire are shown in Table 2.

[0081] [Table 2]

[0082] The method for preparing the above silver alloy bonding wire was the same as in Example 1.

[0083] <Test Example 1> The silver alloy bonding wires having a diameter of 20 μm according to Example 1 and Comparative Example 1 were subjected to mechanical property tests, and the results are shown in Table 3. The tensile breaking strength and elongation tests were based on the IPC-9702 standard.

[0084] [Table 3]

[0085] As can be seen from Table 3, the silver alloy bonding wire according to the present invention had better tensile breaking strength and elongation than Comparative Example 1.

[0086] The silver alloy bonding wires 1# to 11# according to Example 1 and Comparative Example 1 were subjected to a corrosion resistance test, and the results are shown in FIG.

[0087] As a corrosion resistance test method, the silver alloy bonding wire was immersed in a 0.1 mol / L sodium sulfide aqueous solution at room temperature, and the corrosion resistance data for 200 hours was recorded to obtain a corrosion resistance graph.

[0088] As can be seen from FIG. 1, the corrosion rate of the silver alloy bonding wire according to Example 1 after 200 hours was always maintained at a relatively low level, which was much lower than that of Comparative Example 1, and the corrosion resistance of the silver alloy bonding wire 3# was good.

[0089] The above embodiments are merely for illustrating the technical solutions of the present invention and are not intended to limit the same. Although the present invention has been described in detail with reference to the above embodiments, those skilled in the art may modify the technical solutions described in the above embodiments and make equivalent substitutions for some or all of the technical features therein. These modifications or substitutions do not deviate from the essence of the corresponding technical solutions and the scope of the technical solutions of the embodiments of the present invention.

Claims

1. Including core material, The core material contains, by mass fraction, Al: 0.5 wt% to 0.7 wt%, Ce: 0.6 wt% to 1 wt%, carbon nanotubes: 1 wt% to 3 wt%, Sb: 0.3 wt% to 0.5 wt%, and the remainder is Ag. Silver alloy bonding wire.

2. In the core material, the total mass fraction of the Al and the Sb is 1%; And / or, in the core material, the total mass fraction of the Al, the Ce, the carbon nanotubes, and the Sb is 3.5% or less. The silver alloy bonding wire according to claim 1.

3. The carbon nanotubes include single-walled carbon nanotubes. And / or, the carbon nanotube has a diameter of 2 nm or less and a length of 50 nm or less, characterized in that the silver alloy bonding wire according to claim 1.

4. Further comprising a protective layer provided on the surface of the core material, Alternatively, the silver alloy bonding wire according to claim 1 further comprises a protective layer provided on the surface of the core material, wherein the protective layer comprises, by weight, 3 to 5 parts of a film-forming agent, 1 to 3 parts of a surfactant, and 1 to 3 parts of a dissolution aid.

5. the film-forming agent includes at least one of ethylene glycol monovinyl ether, polyacrylate, and polyvinyl acetate; the surfactant includes at least one of polyethylene glycol fatty acid ester, sodium dodecyl sulfate, and sodium dodecylbenzenesulfonate; The silver alloy bonding wire according to claim 4, characterized in that the dissolution aid contains at least one of para-aminobenzoic acid, acetone, and methanol.

6. The diameter of the core material is 15 to 40 μm. And / or, the thickness of the protective layer is 1.5 to 4 μm, characterized in that the silver alloy bonding wire according to claim 4.

7. A method for preparing the silver alloy bonding wire according to any one of claims 1 to 6, comprising: Step S1: melting and pouring the Ag / Ce intermediate alloy, the Sb raw material, the Al foil, and the carbon nanotubes in this order to obtain a rod; A method for preparing a silver alloy bonding wire, comprising: a step S2 of extruding and drawing the rod material in sequence to obtain the core material.

8. In step S2, the extrusion temperature is 700 to 750 ° C. And / or, the method for preparing a silver alloy bonding wire as claimed in claim 7, characterized in that the extrusion ratio of the extrusion is 3 to 4.

5.

9. (1) further comprising the step of sequentially performing cleaning, annealing, and immersion treatment on the core material to obtain the silver alloy bonding wire; (2) The annealing temperature is 450 to 500°C; and (3) the immersion treatment includes immersing the core material after the annealing treatment in a protective agent to obtain a protective layer, and the protective agent includes, by weight, 3 to 5 parts of a film-forming agent, 1 to 3 parts of a surfactant, 1 to 3 parts of a solubilizing agent, and 70 to 80 parts of a solvent; 8. The method for preparing a silver alloy bonding wire according to claim 7, characterized in that it comprises at least one of the following:

10. 7. Use of the silver alloy bonding wire according to any one of claims 1 to 6 in electronic packaging.

Images