Bonding wire, its preparation method and LED device

Abstract

To provide a bonding wire having superior mechanical properties, high-temperature stability, and reliability.SOLUTION: The present invention belongs to the technical field of packaging materials, and particularly relates to a bonding wire, a preparation method thereof, and an LED device. The bonding wire of the present invention includes a core material, and the core material contains, in percentage by mass, 5 wt.% to 10 wt.% of Cu, 2 wt.% to 7 wt.% of graphene, 0.25 wt.% to 0.5 wt.% of Sm, and 1 wt.% to 1.5 wt.% of Zr, and the balance of Ag. The present invention adds a Zr element and graphene into the bonding wire, and reasonably controls contents of the Zr element and the graphene. At the same time, by cooperation of the Zr element and the graphene with a Cu element and an Sm element, the present invention improves mechanical properties, corrosion resistance, high-temperature stability, electromigration resistance, and reliability of the silver alloy bonding wire. The present invention can meet bonding requirements of high-power LED devices in complex bonding environments such as low loop formation and sustained high temperature.SELECTED DRAWING: None

Description

[Technical Field]

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

[0002] Wire bonding is the most common interconnection method for IC packaging. As the vital path of the lead frame for chip connection, it fulfills the functions of signal transmission and electrical connection. It is one of the essential basic raw materials for the repackaging manufacturing process of integrated circuits, semiconductor discrete devices and LED light source devices. Bonding wire mainly includes gold wire, silver wire, copper wire, aluminum wire, etc. Summary of the Invention [Problem to be solved by the invention]

[0003] As integrated circuits and semiconductor packaging become more multi-lead, highly integrated, and miniaturized, the impact of bonding wire on devices becomes increasingly significant, necessitating the use of narrower-diameter, longer-distance bonding wire with better electrochemical performance. Gold bonding wire is expensive, copper bonding wire is highly susceptible to oxidation and has poor performance, and aluminum wire is used in low-end products. In contrast, silver bonding wire has excellent electrical and thermal performance, can reduce high-frequency noise in devices, can reduce heat generation in high-power LEDs, has good stability, and is cost-effective, making it widely used in microelectronic packaging. However, silver bonding wire often suffers from problems such as low bonding strength, unstable performance, poor corrosion resistance and high-temperature stability, and can cause high-power devices to malfunction due to overheating, significantly limiting its development. In view of this, the present invention has been devised.

[0004] A first object of the present invention is to provide a bonding wire having excellent mechanical properties, high temperature stability and reliability.

[0005] A second object of the present invention is to provide a method for preparing a bonding wire that can improve the mechanical properties, high-temperature stability, and reliability of the bonding wire.

[0006] A third object of the present invention is to provide an LED device with excellent 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 bonding wire, which includes a core material containing, by mass fraction, 5 wt% to 10 wt% Cu, 2 wt% to 7 wt% graphene, 0.25 wt% to 0.5 wt% Sm, 1 wt% to 1.5 wt% Zr, and the remainder being Ag.

[0009] Furthermore, the mass ratio of the Cu to the Sm is (19-21):1.

[0010] Furthermore, at least one of the following is satisfied: (1) the graphene includes single-layer graphene; (2) the particle size of the single-layer graphene is 0.1 to 0.5 μm; and (3) the thickness of the single-layer graphene is less than 1 nm.

[0011] The core material may further include a protective layer provided on the surface thereof, and / or the protective layer provided on the surface thereof may include one or more of Al2O3, ZrO2, and SiO2.

[0012] Furthermore, the bonding wire has at least one of the following characteristics: (1) a diameter of 15 to 25 μm; (2) a thickness of the protective layer of 0.3 to 2 μm; and (3) a ratio of the thickness of the protective layer to the diameter of (0.02 to 0.08):1.

[0013] The present invention further provides a method for preparing the above-mentioned bonding wire, which includes step S1 of vacuum gas atomizing an Ag / Cu / Sm intermediate alloy to obtain intermediate alloy powder, and step S2 of mixing the intermediate alloy powder with Zr powder and graphene powder, followed by mold pressing, vacuum sintering, extrusion, and drawing to obtain a wire.

[0014] Furthermore, in step S1, the pressure of the vacuum gas atomization is 10 to 12 MPa, and / or the particle size D50 of the intermediate alloy powder is 35 to 50 μm.

[0015] Furthermore, in step S2, at least one of the following is included: (1) the mold press pressure is 150 to 200 MPa; (2) the vacuum sintering includes sintering at 780 to 800°C for 3 to 5 hours; and (3) the extrusion temperature is 750 to 780°C and the extrusion speed is 4 to 7 mm / s.

[0016] Furthermore, the above-mentioned method for preparing a bonding wire further includes a step of performing vapor phase growth on the surface of the wire to obtain a protective layer, and / or a step of performing vapor phase growth on the surface of the wire to obtain a protective layer, and then performing a wiredrawing process after the vapor phase growth.

[0017] The present invention further provides an LED device, which includes the above-described bonding wire or a bonding wire prepared by the above-described method for preparing a bonding wire.

[0018] Compared with the prior art, the present invention has the following beneficial effects: 1. The bonding wire of the present invention optimizes the components of the silver alloy, adding Zr and graphene to the silver alloy, and by cooperating with Cu and Sm, improves the mechanical properties of the silver alloy bonding wire, resulting in relatively high strength and tensile breaking strength, allowing for fine processing. The bonding wire also improves the electromigration resistance, high temperature resistance and reliability, which can meet the requirements of high-power LED packaging and can be used for bonding high-power LED devices in complex bonding environments such as low loops and sustained high temperatures. 2. The bonding wire according to the present invention can further improve the corrosion resistance of the bonding wire by providing a protective layer on the surface of the silver alloy core material. 3. The bonding wire preparation method of the present invention employs the processes of atomization powder preparation, mold pressing, vacuum sintering and extrusion, and introduces graphene with a high melting point to distribute it uniformly throughout the bonding wire system, thereby producing a bonding wire with excellent performance. DETAILED DESCRIPTION OF THE INVENTION

[0019] The following specific embodiments are used to clearly and completely explain the technical solutions of the present invention. Those skilled in the art will understand that the described examples are only some of the examples of the present invention, not all of the examples, and are only intended to illustrate the present invention and not to limit the scope of the present invention. All other examples obtained by those skilled in the art based on the examples of the present invention without using their inventive abilities also fall within the scope of protection of the present invention. In the examples, where specific conditions are not specified, they can be carried out under conventional conditions or conditions recommended by the manufacturer. For reagents or equipment for which the preparation manufacturer is not specified, conventional commercially available products can be used.

[0020] The term "and / or" as used herein represents a relationship between related objects and represents a three-way relationship, for example, A and / or B represents a three-way relationship in which only A is present, both A and B are present, or only B is present.

[0021] Some embodiments of the present invention provide a bonding wire, the bonding wire including a core material containing, by mass fraction, 5 wt% to 10 wt% Cu, 2 wt% to 7 wt% graphene, 0.25 wt% to 0.5 wt% Sm, 1 wt% to 1.5 wt% Zr, and the remainder Ag.

[0022] The bonding wire according to the present invention includes a core material, which is a silver alloy. Addition of Zr to the core material contributes to the refinement of crystal grains and improves the high-temperature stability of the bonding wire. Graphene, as a nano-reinforcement phase, increases the strength of the bonding wire, pins stacking faults and grain boundaries, effectively inhibits the thermal motion of stacking faults and grain boundaries, and significantly improves the thermal stability of the bonding wire. Addition of Cu increases the ductility and strength of the bonding wire. Addition of Sm accumulates at the grain boundaries, reducing diffusion along the grain boundaries and improving electromigration resistance and reliability.

[0023] The present invention adds Zr and graphene to the bonding wire and rationally controls their contents to contribute to improving the strength and high-temperature stability of the bonding wire, and the cooperation of Cu and Sm contributes to improving cycle temperature stability, strength, electromigration resistance, etc. As described above, the cooperation of each element can improve the basic performance and application reliability of the bonding wire.

[0024] The bonding wire of the present invention has excellent mechanical properties, relatively high strength and tensile breaking strength, is capable of being finely processed, and has excellent corrosion resistance, high temperature resistance and electromigration resistance, and can meet the requirements for bonding high-power LED devices in complex bonding environments such as low loops and sustained high temperatures.

[0025] In some embodiments of the present invention, as representative and non-limiting examples, the mass fraction of Cu in the core material is 5 wt%, 5.5 wt%, 6 wt%, 6.5 wt%, 7 wt%, 7.5 wt%, 8 wt%, 8.5 wt%, 9 wt%, 9.5 wt%, 10 wt%, or a value within a range consisting of any two values ​​therein, and the mass fraction of graphene is 2 wt%, 2.5 wt%, 3 wt%, 3.5 wt%, 4 wt%, 4.5 wt%, 5 wt%, 6 wt%, 7 wt%, 8 wt%, 9 wt%, 9.5 wt%, 10 wt%, or a value within a range consisting of any two values ​​therein. the mass fraction of Sm is 0.2 wt%, 0.3 wt%, 0.4 wt%, 0.5 wt%, or a value within a range consisting of any two values ​​thereof; and the mass fraction of Zr is 1 wt%, 1.1 wt%, 1.2 wt%, 1.3 wt%, 1.4 wt%, 1.5 wt%, or a value within a range consisting of any two values ​​thereof.

[0026] In some embodiments of the present invention, the core material contains, by mass fraction, 6.5 wt% to 7.5 wt% Cu, 4.5 wt% to 5.5 wt% graphene, 0.3 wt% to 0.4 wt% Sm, 1.1 wt% to 1.3 wt% Zr, and the remainder is Ag.

[0027] In the present invention, by further optimizing the components of the core material and setting each component within the above range, a bonding wire with even better performance can be obtained.

[0028] In some embodiments of the present invention, the mass ratio of Cu to Sm is (19 to 21):1, and preferably 20:1. The cooperation of Cu and Sm can contribute to improving the strength and cycle temperature stability of the bonding wire.

[0029] In some embodiments of the present invention, the core material has a total mass fraction of Cu and graphene of 12%. The cooperation of Cu and graphene can contribute to improving the strength, high-temperature stability, and reliability of the bonding wire.

[0030] In some embodiments of the present invention, the graphene comprises single layer graphene.

[0031] In some embodiments of the present invention, the particle size of the single-layer graphene is 0.1 to 0.5 μm.

[0032] In some embodiments of the present invention, the thickness of the single layer graphene is less than 1 nm.

[0033] If the graphene particle size is too large, the mechanical properties of the alloy will deteriorate, and if the graphene particle size is too small, it will aggregate during melting and will not be distributed uniformly.

[0034] In some embodiments of the present invention, the bonding wire further includes a protective layer provided on the surface of the core material.

[0035] In some embodiments of the present invention, the protective layer comprises one or more of Al2O3, ZrO2, and SiO2. For example, the protective layer is an Al2O3 layer, a ZrO2 layer, or a SiO2 layer.

[0036] The protective layer according to the present invention has insulating properties, corrosion resistance, and abrasion resistance, and in cooperation with the core material, can further improve the strength of the bonding wire.

[0037] In some embodiments of the present invention, the diameter of the bonding wire is 15 to 25 μm, and representatively and non-limitingly, for example, 15 μm, 20 μm, 25 μm, or a value within a range consisting of any two values ​​therein.

[0038] In some embodiments of the present invention, the thickness of the protective layer is 0.3 to 2 μm, and representative and non-limiting examples thereof include 0.3 μm, 0.5 μm, 1 μm, 1.5 μm, 2 μm, or a value within a range consisting of any two values ​​therein.

[0039] In some embodiments of the present invention, the ratio of the thickness of the protective layer to the diameter of the bonding wire is (0.02-0.08):1.

[0040] In some embodiments of the present invention, the tensile breaking strength of the bonding wire is 5 to 6 g, and preferably 5.5 to 6 g.

[0041] In some embodiments of the present invention, the elongation of the bonding wire is 8% to 9%, and preferably 8.5% to 9%.

[0042] In some embodiments of the present invention, the minimum loop height of the bonding wire is 80 μm, preferably less than 70 μm.

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

[0044] Step S1: Vacuum gas atomization is performed on the Ag / Cu / Sm intermediate alloy to obtain intermediate alloy powder.

[0045] Step S2: After mixing the intermediate alloy powder, Zr powder, and graphene powder, the mixture is mold-pressed, vacuum-sintered, extruded, and drawn in this order to obtain a wire.

[0046] The method for preparing a bonding wire according to the present invention employs processes of atomization powder preparation, mold pressing, vacuum sintering, and extrusion to introduce graphene, which has a high melting point, into a silver alloy system and distribute it uniformly throughout the silver alloy. Utilizing the properties of graphene, which have high strength, high thermal conductivity, and ultra-high temperature stability, the strength, high temperature stability, and electromigration resistance of the bonding wire can be improved.

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

[0048] The Ag raw material, Cu raw material, and Sm raw material were weighed according to the blending ratio and placed in a crucible in a vacuum furnace. The furnace door was closed and a 3×10 -2 When the chamber is evacuated to a pressure of 0.1 to 0.3 Pa and filled with argon gas to a pressure of 0.1 to 0.3 Pa and heated to 600 to 800°C, the pressure drops to 2×10 -2 The mixture is again evacuated to 1000 Pa, and argon gas is added to 0.1-0.3 Pa. The temperature is raised to 1150-1200°C and refined for 20-30 minutes, stirring in one direction using a magnetic stirrer bar during this time. After cooling in the furnace, an Ag / Cu / Sm intermediate alloy is obtained. Preferably, the purity of each of the Ag, Cu, and Sm raw materials is greater than 99.99%. The crucible includes a high-purity graphite crucible.

[0049] In some embodiments of the present invention, the pressure of the vacuum gas atomization in step S1 is 10 to 12 MPa.

[0050] In some embodiments of the present invention, the cooling rate of the molten metal in the vacuum gas atomization process in step S1 is 100 to 105° C. / s.

[0051] In some embodiments of the present invention, the particle size D50 of the intermediate alloy powder in step S1 is 35 to 50 μm.

[0052] In some embodiments of the present invention, in step S2, mixing includes weighing the intermediate alloy powder, Zr powder, and graphene powder according to a formulation relationship and performing ball milling. Preferably, the rotation speed of the ball milling is 300 to 500 r / min. The ball milling time is 5 to 7 hours. The volume ratio of balls to materials in the ball milling is 3:1. Preferably, the Zr powder has a purity of 99.9% or more and a particle size of 35 to 50 μm.

[0053] In some embodiments of the present invention, the pressure of the mold pressing in step S2 is 150 to 200 MPa. Preferably, the mold pressing includes pre-press molding the mixed material after mixing in a mold having a diameter of 30 to 50 mm.

[0054] In some embodiments of the present invention, the vacuum sintering in step S2 includes sintering at 780 to 800°C for 3 to 5 hours. Preferably, the vacuum degree in the vacuum sintering process is 2×10 -2 It is Pa.

[0055] In some embodiments of the present invention, the extrusion temperature in step S2 is 750 to 780° C., and the extrusion speed is 4 to 7 mm / s. Preferably, a rod having a diameter of 12 to 15 mm is obtained by extrusion.

[0056] 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.

[0057] In some embodiments of the present invention, in step S2, the extruded rod is subjected to a first wiredrawing process to obtain a wire having a diameter of 0.6 to 1.0 mm. If the diameter of the wire exceeds 6 mm, the deformation rate of the wire is 12% to 15%, and if the diameter of the wire is less than 6 mm, the deformation rate is 8% to 10%.

[0058] In some embodiments of the present invention, the heat treatment in step S2 is performed by heat treating the wire rod after the first wiredrawing at 400 to 450°C for 3 to 5 hours. Preferably, the heat treatment is performed at a temperature rise rate of 2 to 3.5°C / s and at a vacuum degree of 10 -2 It is over Pa.

[0059] In some embodiments of the present invention, the second wiredrawing process in step S2 includes performing multiple passes of drawing on the heat-treated wire to obtain a wire having a size of φ0.07 to 0.1 mm. If the diameter of the wire exceeds 0.5 mm, the deformation rate is 8% to 11%, and the wiredrawing speed is 7 to 10 m / s. If the diameter of the wire is less than 0.5 mm, the deformation rate is 7% to 10%, and the wiredrawing speed is 3 to 5 m / s.

[0060] In some embodiments of the present invention, the method for preparing a bonding wire includes vapor deposition on the surface of a core material to obtain a protective layer.

[0061] In some embodiments of the present invention, the method for preparing the protective layer comprises the following steps.

[0062] After the second wire drawing process, the wire is subjected to continuous vacuum deposition equipment, with high-purity Al, Si, or Ti as the target material, and high-purity Ar2 and O2 as the sputtering and reactive gases. Magnetron sputtering vacuum deposition technology is then used to uniformly sputter the surface to form a protective layer of 1 to 10 μm.

[0063] In some embodiments of the present invention, the vapor phase growth process further includes a wire drawing process. Preferably, the vapor phase growth process is performed on the wire to obtain a bonding wire having a diameter of 15 to 25 μm. The wire drawing process is performed at a drawing speed of 2 to 4 m / s and a deformation ratio of 6% to 8%.

[0064] Some embodiments of the present invention further provide an LED device, which includes the above-described bonding wire or a bonding wire prepared by the above-described method for preparing a bonding wire.

[0065] The bonding wire according to the present invention can meet the requirements of high-power LED packaging, and can be used to bond high-power LED devices in complex bonding environments such as low loop, sustained high temperature, etc.

[0066] Example 1 This example provides a method for preparing a bonding wire. The components and contents (mass fractions) of the core material of the prepared bonding wire are shown in Table 1.

[0067] [Table 1]

[0068] Specifically, the above-mentioned bonding wire preparation method includes the following steps:

[0069] Step S1: Weigh out Ag, Cu, and Sm raw materials with a purity of over 99.99%, and place the weighed raw materials into a high-purity graphite crucible in a vacuum furnace according to the formulation. Close the furnace door and pour 3 × 10 -2 When the chamber is evacuated to a pressure of 0.1 to 0.3 Pa and filled with argon gas to a pressure of 0.1 to 0.3 Pa and heated to 600 to 800°C, the pressure drops to 2×10 -2 The mixture was again evacuated to 1000 Pa, and argon gas was added to 0.1-0.3 Pa. The mixture was heated to 1150-1200°C and refined for 20-30 minutes, during which time it was stirred in one direction using a magnetic stirrer bar. The mixture was then cooled in the furnace to obtain an Ag / Cu / Sm intermediate alloy.

[0070] Step S2: Vacuum gas atomization was performed on the Ag / Cu / Sm intermediate alloy to obtain intermediate alloy powder with a particle size D50 of 35-50 μm, the atomizing gas pressure was 10-12 MPa, and the cooling rate of the molten metal was 100-105°C / s.

[0071] Step S3: According to the formulation, the weighed intermediate alloy powder, Zr powder (purity: 99.9%, particle size: 35-50 μm), and single-layer graphene powder (particle size D50: 0.1-0.5 μm, thickness: less than 1 nm) were ball milled to obtain a mixed material, where the volume ratio of balls to materials was 3:1, the rotation speed was 300-500 r / min, and the ball milling time was 5-7 h.

[0072] Step S4: The mixed material is press-molded into a mold of φ30-50 mm at a pressure of 150-200 MPa, and then 2 × 10 -2 The mixture was sintered at a temperature of 780-800°C under a vacuum of 100 Pa for 3-5 h.

[0073] Step S5: After sintering, extrusion was carried out to obtain a bar material with a size of φ12 to 15 mm, the extrusion temperature was 750 to 780° C., and the extrusion speed was 4 to 7 mm / s.

[0074] Step S6: A rod having a diameter of 12 to 15 mm is drawn into a wire having a diameter of 0.6 to 1.0 mm using a wire drawing machine. If the diameter of the wire is greater than 6 mm, the deformation rate of the wire is 12% to 15%, and if the diameter is less than 6 mm, the deformation rate is 8% to 10%.

[0075] Step S7: Put the wire rod with a diameter of 0.6 to 1.0 mm into a vacuum annealing furnace. -2 The temperature was raised to 400 to 450°C at a rate of 2 to 3.5°C / s under a vacuum of over 100 Pa, and the heat treatment was carried out for 3 to 5 hours.

[0076] Step S8: The heat-treated wire is subjected to multiple passes of drawing using a multi-wire drawing machine to produce a wire of φ0.07 to 0.1 mm in size. If the diameter of the wire is greater than 0.5 mm, the deformation rate is 8% to 11% and the drawing speed is 7 to 10 m / s. If the diameter of the wire is less than 0.5 mm, the deformation rate is 7% to 10% and the drawing speed is 3 to 5 m / s.

[0077] Step S9: For wires with a diameter of 0.07 to 0.1 mm, a continuous vacuum deposition facility was used, Si was used as the target material, P-type single crystal Si was used, high-purity Ar2 and O2 were used as the sputtering gas and reactive gas, and magnetron sputtering vacuum deposition technology was used to uniformly sputter the surface to form a 1 to 10 μm thick SiO2 protective layer.

[0078] Step S10: The wire after magnetron sputtering is drawn into a diameter of 15 μm using a wire drawing machine, with a drawing speed of 2 to 4 m / s and a deformation rate of 6% to 8%, and then ultrasonically cleaned for more than 30 minutes, dried by spraying nitrogen gas, wound on a reel and packaged to obtain a bonding wire.

[0079] <Comparative Example 1> This comparative example provided a method for preparing a bonding wire. The components and contents (mass fractions) of the core material of the prepared bonding wire are shown in Table 2.

[0080] [Table 2]

[0081] The preparation method of the above bonding wires is referred to in Example 1.

[0082] <Test Example 1> The bonding wires of Example 1 and Comparative Example 1, each having a diameter of 15 μm, were subjected to mechanical property tests, and the results are shown in Table 3.

[0083] The tensile breaking strength and elongation tests were based on the IPC-9702 standard.

[0084] Tests were conducted using the bonding wires of Example 1 and Comparative Example 1 on Al pads of a memory, and the results are shown in Table 3.

[0085] HTST (High Temperature Storage Test): The test condition is 150°C, and the standard JESD22-A103-A is referenced.

[0086] TCT (Temperature Cycling Aging Test): The test conditions were -55 to 125°C, and the standard JESD22-A104-A was referenced.

[0087] [Table 3]

[0088] As can be seen from Table 3, compared to Comparative Example 1, the bonding wire according to the present invention had a higher tensile breaking strength and elongation, a relatively small minimum loop height, and better bonding reliability.

[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, Cu: 5 wt% to 10 wt%, graphene: 2 wt% to 7 wt%, Sm: 0.25 wt% to 0.5 wt%, Zr: 1 wt% to 1.5 wt%, and the balance is Ag. Bonding wire.

2. The bonding wire according to claim 1, characterized in that the mass ratio of the Cu to the Sm is (19-21):

1.

3. (1) The graphene includes a single-layer graphene; (2) the particle size of the single-layer graphene is 0.1 to 0.5 μm; and (3) the thickness of the single layer graphene is less than 1 nm; 2. The bonding wire according to claim 1, comprising at least one of:

4. Further comprising a protective layer provided on the surface of the core material, Alternatively, the core material may further include a protective layer provided on the surface thereof, and the protective layer may include Al ２ O ３ , ZrO ２ and SiO ２ 2. The bonding wire according to claim 1, wherein the bonding wire comprises one or more of the following:

5. (1) The diameter is 15 to 25 μm. (2) The thickness of the protective layer is 0.3 to 2 μm. and (3) the ratio of the thickness of the protective layer to the diameter is (0.02-0.08):1; 5. The bonding wire according to claim 4, comprising at least one of:

6. A method for preparing a bonding wire according to any one of claims 1 to 5, comprising: Step S1: subjecting the Ag / Cu / Sm intermediate alloy to vacuum gas atomization to obtain intermediate alloy powder; and step S2 of mixing the intermediate alloy powder, Zr powder, and graphene powder, and then performing mold pressing, vacuum sintering, extrusion, and drawing in that order to obtain a wire.

7. In step S1, The pressure of the vacuum gas atomization is 10 to 12 MPa. And / or, the particle size D50 of the intermediate alloy powder is 35 to 50 μm, characterized in that the method for preparing a bonding wire according to claim 6.

8. In step S2, (1) The pressure of the mold press is 150 to 200 MPa; (2) The vacuum sintering includes sintering at 780 to 800°C for 3 to 5 hours; and (3) the temperature of the extrusion is 750 to 780°C and the speed of the extrusion is 4 to 7 mm / s; 7. The method for preparing a bonding wire according to claim 6, further comprising at least one of:

9. Further comprising a step of performing vapor deposition on the surface of the wire to obtain a protective layer. Alternatively, the method for preparing a bonding wire according to claim 6 further comprises a step of performing vapor deposition on the surface of the wire to obtain a protective layer, and performing a wire drawing process after the vapor deposition.

10. An LED device comprising the bonding wire according to any one of claims 1 to 5.

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