Gold alloy bonding wire and preparation method thereof

Abstract

The present application relates to the field of alloy bonding wires, and in particular to a gold alloy bonding wire and a preparation method thereof. The gold alloy bonding wire, in terms of mass percentage, includes: Ag 5-15%, Cu 0.5-2%, Pt 0.5-2%, Pd 1-3%, In 0.001-0.003%, Ge 0.001-0.005%, Ce0.002-0.003%, Si 0.01-0.03%, Ni 0.003-0.0045%, Be 0.001-0.005%, Re 0.01-0.02%, and the remainder is Au. The gold alloy bonding wire prepared by the present application can retain excellent reliability and conductivity while having excellent elongation, tensile strength and other properties, and has very excellent market value.

Description

Technical Field

[0001] The present application relates to the field of alloy bonding wires, and in particular to a gold alloy bonding wire and a preparation method thereof. Background Art

[0002] Bonding wire (also known as bonding wire) is the main connection method between the chip and the external packaging substrate (substrate) and / or the multilayer circuit board (PCB). The development trend of bonding wire, from the product development direction, is mainly in the direction of wire diameter miniaturization, high workshop life and high spool length; and from the chemical composition, copper wire (including bare copper wire, palladium-plated copper wire, gold-flashed palladium-plated copper wire) has largely replaced gold wire in the semiconductor field, while silver wire and silver alloy wire have replaced gold wire in LED and some IC packaging applications. Another important direction is the development of gold alloy wire to further reduce costs and maintain or improve the various performance requirements of the bonding process.

[0003] Due to the development requirements of miniaturization and thinning of electronic products, the semiconductor industry has responded by thinning the chip thickness, packaging using chip stacking, flip chip, wafer-level packaging, 2.5D and 3D packaging, etc. However, traditional bonding packaging is still the mainstream packaging form. Traditional gold bonding wire has extremely strong chemical stability and electrical and thermal conductivity, but its preparation cost is subject to the gold price, which easily leads to excessively high cost of the final product and too little profit. In addition, pure gold bonding wire also has the problems of low tensile strength, low elongation and poor reliability. The improvement scheme for gold bonding wire in the prior art is to prepare alloy bonding wire, the cost of which can be effectively controlled, such as silver-gold alloy bonding wire. However, in some product fields and environments, the requirements for the reliability and bonding of bonding wires are high. Although the emergence of such alloy bonding wires can effectively reduce costs, there will be problems with reliability and mechanical properties.

[0004] Therefore, in order to solve the above problems, the present application provides a gold alloy bonding wire and a preparation method thereof. The gold alloy bonding wire prepared in the present application can have excellent elongation, tensile strength and other properties while retaining excellent reliability, and has very excellent market value. Summary of the invention

[0005] In order to solve the above problems, the first aspect of the present application provides a gold alloy bonding wire, which includes, by mass percentage, 5-15% Ag, 0.5-2% Cu, 0.5-2% Pt, 1-3% Pd, 0.001-0.003% In, 0.001-0.005% Ge, 0.002-0.003%, Si0.01-0.03%, Ni 0.003-0.0045%, Be 0.001-0.005%, Re 0.01-0.02%, and the balance is Au.

[0006] As a preferred solution, the mass ratio of Ag, Cu, Pt and Pd is (6-12):(1-1.5):(0.6-1.2):(1-2).

[0007] As a preferred solution, the mass ratio of Ag, Cu, Pt and Pd is (10-12):(1-1.2):(0.8-1):1.5.

[0008] As a preferred solution, the mass ratio of Ag, Si and Re is (6-12): (0.015-0.03): (0.01-0.015).

[0009] As a preferred solution, the mass ratio of Ag, Si and Re is (10-12): (0.02-0.03): 0.015.

[0010] The second aspect of the present application provides a method for preparing the above-mentioned gold alloy bonding wire, and the preparation method comprises the following steps: S1 melting and casting: under the protection of inert gas, all metal raw materials required for the gold alloy bonding wire are placed in a vacuum melting furnace, melted at 1200-1600°C, and cast into alloy columns; S2 wire drawing: the alloy column is drawn on a wire drawing machine, and the wire drawing process is divided into four stages of pre-wire drawing, coarse wire drawing, fine wire drawing and ultra-fine wire drawing. After the wire drawing is completed, a 20-25μm gold wire is obtained; S3 annealing: under the protection of protective gas, the annealing temperature and annealing rate of the gold wire are controlled for annealing; S4 post-treatment: after the annealing is completed, the obtained gold wire is wound and collected and the finished product is inspected to ensure that the surface is smooth and undamaged, so as to obtain the gold alloy bonding wire.

[0011] In the present application, by limiting the compounding ratio of Ag and other added metals in the above scheme, the oxidation resistance and stability of the bonding wire can be effectively improved while ensuring the various mechanical properties of the bonding wire. In the present application, Ag and Cu metals are added to the Au alloy compound, which can effectively improve the conductivity of the bonding wire, but the presence of Ag and Cu is also likely to lead to unstable oxidation and sulfurization properties. Therefore, Pt and Si are further added to improve the oxidation resistance and other properties of the bonding wire. The addition of Si in the present application is relatively large. Although it can significantly improve the softening temperature and high-temperature oxidation resistance of the alloy, it also has a certain amplitude effect on the mechanical strength. In the present application, Re is further added to compound with Si, which can give full play to the effect of Re in slowing down grain boundary diffusion and inhibiting grain boundary sliding at high temperature in the alloy bonding wire, thereby improving the mechanical properties of the alloy bonding wire. On the other hand, in addition to being able to exert its excellent anti-sulfurization performance, the addition of Re can also significantly increase the recrystallization temperature of the bonding wire metal, so a higher temperature is required to transform into an annealing state, which has better dimensional stability, and by hindering grain growth, promotes the formation of a fine and uniform grain structure, thereby improving the toughness and fatigue strength of the alloy.

[0012] As a preferred solution, the specific steps of the S1 melting and casting are: (1) Au, Cu, Pt, Pd and part of Ag are melted in a melting furnace, the protective gas is argon, the melting temperature is 1200-1400°C, the time is 25-40 min, and an alloy ingot is obtained after cooling after melting. The alloy ingot is processed into an alloy cube, and then the remaining Ag block is taken, and the remaining metal raw material is injected into the center of the Ag block, and then kneaded into an Ag cube of the same size as the alloy ingot; (2) Subsequently, the Ag cube and the alloy cube are stacked into a combination, with the Ag cube located in the center and surrounded by the alloy cube, and placed in a high vacuum continuous casting machine for melting under high-purity argon. After complete melting, it is stirred evenly and cast into an alloy column.

[0013] As a preferred solution, the melting temperature of the high vacuum continuous casting machine is 1400-1500°C.

[0014] As a preferred solution, the melting time of the high vacuum continuous casting machine is 30 to 50 minutes.

[0015] As a preferred solution, the vacuum degree of the high vacuum continuous casting machine is 1.5×10 -2 ~3.8×10 -2 Pa.

[0016] As a preferred solution, the diameter of the alloy column is 5 to 8 mm.

[0017] As a preferred scheme, the specific steps of the S2 wire drawing are: (1) pre-drawing the alloy column material, controlling the processing deformation amount, and obtaining a pre-drawn section bonding wire; (2) coarse drawing the pre-drawn bonding wire, heating it to 120-140°C, controlling the processing deformation amount, and obtaining a coarse-drawn bonding wire; (3) fine drawing the coarse-drawn bonding wire, heating it to 150-160°C, controlling the processing deformation amount, and obtaining a fine-drawn bonding wire; (4) ultra-fine drawing the fine-drawn bonding wire, heating it to 180-200°C, controlling the processing deformation amount, and obtaining an ultra-fine bonding wire.

[0018] As a preferred solution, the processing deformation amount of the pre-drawing is 15-20%.

[0019] As a preferred solution, the processing deformation amount of the rough wire drawing is 10-12%.

[0020] As a preferred solution, the processing deformation amount of the fine wire drawing is 5-8%.

[0021] As a preferred solution, the processing deformation amount of the ultra-fine wire drawing is 2-4%.

[0022] As a preferred solution, the diameter of the ultra-fine bonding wire is 20-25 μm.

[0023] As a preferred solution, the specific steps of the S3 annealing are: using nitrogen as the annealing atmosphere, annealing the ultra-fine bonding wire twice in succession, the effective annealing length is 700-1000mm, the annealing temperature is 700-1000°C, the annealing rate is 50-80m / min, and naturally cools to room temperature after the two annealings are completed.

[0024] As a preferred solution, the effective length of the annealing is 800-900 mm.

[0025] As a preferred solution, the first annealing temperature is 880-900°C.

[0026] As a preferred solution, the annealing rate at the first annealing temperature is 55-60 m / min.

[0027] As a preferred solution, the second annealing temperature is 720-740°C.

[0028] As a preferred solution, the annealing rate at the second annealing temperature is 70-74 m / min.

[0029] In the present application, through the smelting and annealing schemes in the above-mentioned preparation method, the mixing uniformity of the added metal in the smelting stage can be further controlled, and the smelting and annealing temperatures are increased due to the increase in the recrystallization temperature. In addition, through secondary annealing, the mixed metal's assistance in forming stable and small-sized grains is fully utilized, thereby enhancing the interaction between the mixed metals, optimizing the microstructure inside the alloy bonding wire, and ultimately further improving its mechanical properties while ensuring good conductivity.

[0030] The beneficial effects of this application are:

[0031] 1. The gold alloy bonding wire prepared in this application can retain excellent reliability and conductivity while having excellent elongation, tensile strength and other properties, and has very excellent market value.

[0032] 2. A gold alloy bonding wire prepared in the present application can effectively improve the oxidation resistance and stability of the bonding wire while ensuring the various mechanical properties of the bonding wire by limiting the compounding ratio of Ag and other added metals; and the compounding of Re and Si can give full play to the effect of Re in slowing down grain boundary diffusion and inhibiting grain boundary sliding at high temperature in the alloy bonding wire, thereby improving the mechanical properties of the alloy bonding wire; on the other hand, the addition of Re can not only exert its excellent anti-sulfurization performance, but also significantly increase the recrystallization temperature of the bonding wire metal, so a higher temperature is required to transform into the annealing state, with better dimensional stability, and by hindering grain growth, promote the formation of a fine and uniform grain structure, thereby improving the toughness and fatigue strength of the alloy.

[0033] 3. A gold alloy bonding wire prepared in the present application can further control the mixing uniformity of the added metal in the melting stage through its specific melting and annealing scheme, and because the recrystallization temperature is increased, the melting and annealing temperatures are increased. Through secondary annealing, the mixed metal can fully play its auxiliary role in forming stable and small-sized grains, thereby enhancing the interaction between the mixed metals and optimizing the internal microstructure of the alloy bonding wire, ultimately further improving its mechanical properties while ensuring good conductivity. DETAILED DESCRIPTION

[0034] The following will further explain and demonstrate the technical solutions in the above invention content of this application in the form of specific implementation schemes. The following embodiments are only practical examples used to illustrate and explain the contents of the technical solutions in the specification, and should not limit the scope of the claims to be protected by this application. All technical products based on the technical solutions described in the invention content of this application should be included in the scope to be protected by this application.

[0035] In the following examples, unless otherwise specified, the raw materials are all commercially available products, or can be prepared by methods well known to those skilled in the art.

[0036] Example 1

[0037] Embodiment 1 A first aspect provides a gold alloy bonding wire, which comprises, by mass percentage, 12% Ag, 1% Cu, 0.8% Pt, 1.5% Pd, 0.002% In, 0.003% Ge, 0.002% Ce, 0.025% Si, 0.004% Ni, 0.002%, 0.002% Be, 0.015% Re, and the balance is Au.

[0038] The second aspect of the present embodiment provides a method for preparing the above-mentioned gold alloy bonding wire, and the preparation method includes the following steps: S1 melting and casting: under the protection of inert gas, all metal raw materials required for the gold alloy bonding wire are placed in a vacuum melting furnace for melting, and cast into alloy columns; S2 wire drawing: the alloy column is drawn on a wire drawing machine, and the wire drawing process is divided into four stages of pre-wire drawing, coarse wire drawing, fine wire drawing and ultra-fine wire drawing. After the wire drawing is completed, a 20μm gold wire is obtained; S3 annealing: under the protection of protective gas, the annealing temperature and annealing rate of the gold wire are controlled for annealing; S4 post-processing: after the annealing is completed, the obtained gold wire is wound and collected and the finished product is inspected to ensure that the surface is smooth and undamaged, so as to obtain the gold alloy bonding wire.

[0039] S1 specific steps of melting and casting: (1) Au, Cu, Pt, Pd and part (80wt% of the total Ag content) of Ag are melted in a melting furnace with argon as the protective gas, the melting temperature is 1250°C, and the time is 30min. After the melting is completed and cooled, an alloy ingot is obtained. The alloy ingot is processed into an alloy cube, and then the remaining Ag block is taken, and the remaining metal raw material is injected into the center of the Ag block, and then kneaded into an Ag cube of the same size as the alloy ingot; (2) Subsequently, the Ag cube and the alloy cube are stacked into a combination, with the Ag cube located in the center and surrounded by the alloy cube. The combination is placed in a high vacuum continuous casting machine under high-purity argon for melting, and after complete melting, it is stirred evenly and cast into an alloy column.

[0040] The melting temperature of the high vacuum continuous casting machine is 1500℃.

[0041] The melting time of the high vacuum continuous casting machine is 45 minutes.

[0042] The vacuum degree of the high vacuum continuous casting machine is 2.2×10 -2 Pa.

[0043] The diameter of the alloy column obtained was 8 mm.

[0044] The specific steps of S2 wire drawing are as follows: (1) pre-drawing the alloy column material, controlling the processing deformation, and obtaining a pre-drawn section bonding wire; (2) coarse-drawing the pre-drawn bonding wire, heating it to 130°C, controlling the processing deformation, and obtaining a coarse-drawn bonding wire; (3) fine-drawing the coarse-drawn bonding wire, heating it to 155°C, controlling the processing deformation, and obtaining a fine-drawn bonding wire; (4) ultra-fine-drawing the fine-drawn bonding wire, heating it to 190°C, controlling the processing deformation, and obtaining an ultra-fine bonding wire.

[0045] The processing deformation of pre-drawn wire is 18%; the processing deformation of coarse drawn wire is 11%; the processing deformation of fine drawn wire is 6%; the processing deformation of ultra-fine drawn wire is 3%; the diameter of ultra-fine bonding wire is 20μm.

[0046] The specific steps of S3 annealing are as follows: nitrogen is used as the annealing atmosphere, and the ultra-fine bonding wire is annealed twice in succession. The effective annealing length is 850mm, the first annealing temperature is 880℃, the first annealing rate is 55m / min, the second annealing temperature is 730℃, and the second annealing rate is 73m / min. After the two annealings are completed, it is naturally cooled to room temperature 25℃.

[0047] Example 2

[0048] Embodiment 2 The first aspect provides a gold alloy bonding wire, which comprises, by mass percentage, 10% Ag, 1.2% Cu, 1% Pt, 1.5% Pd, 0.002% In, 0.003% Ge, 0.002% Ce, 0.02% Si, 0.004% Ni, 0.002%, 0.002% Be, 0.01% Re, and the balance is Au.

[0049] The second aspect of the present embodiment provides a method for preparing the above-mentioned gold alloy bonding wire, and the preparation method includes the following steps: S1 melting and casting: under the protection of inert gas, all metal raw materials required for the gold alloy bonding wire are placed in a vacuum melting furnace for melting, and cast into alloy columns; S2 wire drawing: the alloy column is drawn on a wire drawing machine, and the wire drawing process is divided into four stages of pre-wire drawing, coarse wire drawing, fine wire drawing and ultra-fine wire drawing. After the wire drawing is completed, a 20μm gold wire is obtained; S3 annealing: under the protection of protective gas, the annealing temperature and annealing rate of the gold wire are controlled for annealing; S4 post-processing: after the annealing is completed, the obtained gold wire is wound and collected and the finished product is inspected to ensure that the surface is smooth and undamaged, so as to obtain the gold alloy bonding wire.

[0050] S1 specific steps of melting and casting: (1) Au, Cu, Pt, Pd and part (80wt% of the total Ag content) of Ag are melted in a melting furnace with argon as the protective gas, the melting temperature is 1250°C, and the time is 30min. After the melting is completed and cooled, an alloy ingot is obtained. The alloy ingot is processed into an alloy cube, and then the remaining Ag block is taken, and the remaining metal raw material is injected into the center of the Ag block, and then kneaded into an Ag cube of the same size as the alloy ingot; (2) Subsequently, the Ag cube and the alloy cube are stacked into a combination, with the Ag cube located in the center and surrounded by the alloy cube. The combination is placed in a high vacuum continuous casting machine under high-purity argon for melting, and after complete melting, it is stirred evenly and cast into an alloy column.

[0051] The melting temperature of the high vacuum continuous casting machine is 1500℃.

[0052] The melting time of the high vacuum continuous casting machine is 45 minutes.

[0053] The vacuum degree of the high vacuum continuous casting machine is 2.2×10 -2 Pa.

[0054] The diameter of the alloy column obtained was 8 mm.

[0055] The specific steps of S2 wire drawing are as follows: (1) pre-drawing the alloy column material, controlling the processing deformation, and obtaining a pre-drawn section bonding wire; (2) coarse-drawing the pre-drawn bonding wire, heating it to 130°C, controlling the processing deformation, and obtaining a coarse-drawn bonding wire; (3) fine-drawing the coarse-drawn bonding wire, heating it to 155°C, controlling the processing deformation, and obtaining a fine-drawn bonding wire; (4) ultra-fine-drawing the fine-drawn bonding wire, heating it to 190°C, controlling the processing deformation, and obtaining an ultra-fine bonding wire.

[0056] The processing deformation of pre-drawn wire is 18%; the processing deformation of coarse drawn wire is 11%; the processing deformation of fine drawn wire is 6%; the processing deformation of ultra-fine drawn wire is 3%; the diameter of ultra-fine bonding wire is 20μm.

[0057] The specific steps of S3 annealing are as follows: nitrogen is used as the annealing atmosphere, and the ultra-fine bonding wire is annealed twice in succession. The effective annealing length is 850mm, the first annealing temperature is 880℃, the first annealing rate is 55m / min, the second annealing temperature is 730℃, and the second annealing rate is 73m / min. After the two annealings are completed, it is naturally cooled to room temperature 25℃.

[0058] Example 3

[0059] Embodiment 3 The first aspect provides a gold alloy bonding wire, which comprises, by mass percentage, 12% Ag, 1% Cu, 0.8% Pt, 1.5% Pd, 0.002% In, 0.003% Ge, 0.002% Ce, 0.025% Si, 0.004% Ni, 0.002%, 0.002% Be, 0.015% Re, and the balance is Au.

[0060] The second aspect of the present embodiment provides a method for preparing the above-mentioned gold alloy bonding wire, and the preparation method includes the following steps: S1 melting and casting: under the protection of inert gas, all metal raw materials required for the gold alloy bonding wire are placed in a vacuum melting furnace for melting, and cast into alloy columns; S2 wire drawing: the alloy column is drawn on a wire drawing machine, and the wire drawing process is divided into four stages of pre-wire drawing, coarse wire drawing, fine wire drawing and ultra-fine wire drawing. After the wire drawing is completed, a 20μm gold wire is obtained; S3 annealing: under the protection of protective gas, the annealing temperature and annealing rate of the gold wire are controlled for annealing; S4 post-processing: after the annealing is completed, the obtained gold wire is wound and collected and the finished product is inspected to ensure that the surface is smooth and undamaged, so as to obtain the gold alloy bonding wire.

[0061] S1 specific steps of melting and casting: (1) Au, Cu, Pt, Pd and part (80wt% of the total Ag content) of Ag are melted in a melting furnace with argon as the protective gas, the melting temperature is 1250°C, and the time is 30min. After the melting is completed and cooled, an alloy ingot is obtained. The alloy ingot is processed into an alloy cube, and then the remaining Ag block is taken, and the remaining metal raw material is injected into the center of the Ag block, and then kneaded into an Ag cube of the same size as the alloy ingot; (2) Subsequently, the Ag cube and the alloy cube are stacked into a combination, with the Ag cube located in the center and surrounded by the alloy cube. The combination is placed in a high vacuum continuous casting machine under high-purity argon for melting, and after complete melting, it is stirred evenly and cast into an alloy column.

[0062] The melting temperature of the high vacuum continuous casting machine is 1500℃.

[0063] The melting time of the high vacuum continuous casting machine is 45 minutes.

[0064] The vacuum degree of the high vacuum continuous casting machine is 2.2×10 -2 Pa.

[0065] The diameter of the alloy column obtained was 8 mm.

[0066] The specific steps of S2 wire drawing are as follows: (1) pre-drawing the alloy column material, controlling the processing deformation, and obtaining a pre-drawn section bonding wire; (2) coarse-drawing the pre-drawn bonding wire, heating it to 130°C, controlling the processing deformation, and obtaining a coarse-drawn bonding wire; (3) fine-drawing the coarse-drawn bonding wire, heating it to 155°C, controlling the processing deformation, and obtaining a fine-drawn bonding wire; (4) ultra-fine-drawing the fine-drawn bonding wire, heating it to 190°C, controlling the processing deformation, and obtaining an ultra-fine bonding wire.

[0067] The processing deformation of pre-drawn wire is 18%; the processing deformation of coarse drawn wire is 11%; the processing deformation of fine drawn wire is 6%; the processing deformation of ultra-fine drawn wire is 3%; the diameter of ultra-fine bonding wire is 20μm.

[0068] The specific steps of S3 annealing are as follows: nitrogen is used as the annealing atmosphere, and the ultra-fine bonding wire is annealed twice in succession. The effective annealing length is 850mm, the first annealing temperature is 900℃, the first annealing rate is 60m / min, the second annealing temperature is 720℃, and the second annealing rate is 70m / min. After the two annealings are completed, it is naturally cooled to room temperature 30℃.

[0069] Comparative Example 1

[0070] The specific implementation of this comparative example is basically the same as that of Example 1, except that the gold alloy bonding wire, in terms of mass percentage, includes: Ag 12%, Cu 1%, Pt 0.8%, Pd 1.5%, In 0.002%, Ge 0.003%, Ce0.002%, Si 0.025%, Ni 0.004%, Be 0.002%, and the balance is Au.

[0071] Comparative Example 2

[0072] The specific implementation of this comparative example is basically the same as that of Example 1, except that the gold alloy bonding wire, in terms of mass percentage, includes: Ag 12%, Cu 1%, Pt 0.8%, Pd 1.5%, In 0.002%, Ge 0.003%, Ce0.002%, Si 0.01%, Ni 0.004%, Be 0.002%, Re 0.03%, and the balance is Au.

[0073] Comparative Example 3

[0074] The specific implementation of this comparative example is basically the same as that of Example 1, except that: the processing deformation of pre-drawing is 25%; the processing deformation of coarse drawing is 7%; the processing deformation of fine drawing is 5%; and the processing deformation of ultra-fine drawing is 2%.

[0075] Comparative Example 4

[0076] The specific implementation method of this comparative example is basically the same as that of Example 1, except that: the specific steps of S3 annealing: nitrogen is used as the annealing atmosphere, and the ultra-fine bonding wire is annealed once, the annealing temperature is 800°C, the annealing rate is 65m / min, and after the annealing is completed, it is naturally cooled to room temperature 30°C.

[0077] Comparative Example 5

[0078] The specific implementation method of this comparative example is basically the same as that of Example 1, except that: the specific steps of S3 annealing: nitrogen is used as the annealing atmosphere, and the ultra-fine bonding wire is annealed twice in succession. The effective annealing length is 850 mm, the first annealing temperature is 750° C., the first annealing rate is 40 m / min, the second annealing temperature is 580° C., the second annealing rate is 60 m / min, and the wire is naturally cooled to room temperature 25° C. after the two annealings are completed.

[0079] Performance Evaluation

[0080] Elongation and tensile strength: The elongation and tensile strength of the gold alloy bonding wires prepared in the examples and comparative examples were tested for mechanical properties, and the measured values ​​were recorded in Table 1 as the average value of 10 tests.

[0081] Resistivity: The resistivity of the gold alloy bonding wires prepared in the examples and comparative examples was tested using a bonding wire-specific resistivity tester. The measured values ​​were averaged over 10 tests and recorded in Table 1.

[0082] Table 1

[0083] Example Elongation % Tensile strength cN Resistivity μΩ·cm Example 1 16.45 10.16 1.91 Example 2 15.98 9.98 1.98 Example 3 15.32 9.69 2.04 Comparative Example 1 9.21 6.12 2.34 Comparative Example 2 10.34 7.54 2.29 Comparative Example 3 10.25 7.21 2.21 Comparative Example 4 11.38 7.65 2.19 Comparative Example 5 10.64 6.98 2.16

[0084] From the examples and comparative examples of the present application and the data results in Table 1, it can be seen that the examples 1 to 3 adopting the necessary technical solutions given in the present application have achieved excellent results in terms of mechanical properties and electrical conductivity of the bonding wire, and can have good oxidation resistance and anti-sulfurization while ensuring the above excellent performance, thereby greatly improving the stability and reliability of the gold alloy bonding wire itself. However, because comparative examples 1 to 5 did not fully adopt the necessary technical solutions described by the applicant, their corresponding test results were significantly worse than those of examples 1 to 3, which better proves the irreplaceable nature of the specific technical solutions of the present application in achieving technical effects and solving technical problems.

Claims

1. A gold alloy bonding wire, characterized in that: Calculated by mass percentage, it includes: Ag 5-15%, Cu 0.5-2%, Pt 0.5-2%, Pd 1-3%, In 0.001-0.003%, Ge 0.001-0.005%, Ce 0.002-0.003%, Si 0.01-0.03%, Ni 0.003-0.0045%, Be 0.001-0.005%, Re 0.01-0.02%, and the balance is Au.

2. The gold alloy bonding wire according to claim 1, characterized in that: The mass ratio of Ag, Cu, Pt and Pd is (6-12):(1-1.5):(0.6-1.2):(1-2).

3. The gold alloy bonding wire according to claim 2, characterized in that: The mass ratio of Ag, Si and Re is (6-12): (0.015-0.03): (0.01-0.015).

4. A method for preparing a gold alloy bonding wire according to any one of claims 1 to 3, characterized in that: The preparation method comprises the following steps: S1 melting and casting: under the protection of inert gas, all metal raw materials required for the gold alloy bonding wire are placed in a vacuum melting furnace, melted at 1200-1600°C, and cast into alloy columns; S2 wire drawing: the alloy column is drawn on a wire drawing machine, and the wire drawing process is divided into four stages of pre-wire drawing, coarse wire drawing, fine wire drawing and ultra-fine wire drawing. After the wire drawing is completed, a 20-25 μm gold wire is obtained; S3 annealing: under the protection of protective gas, the annealing temperature and annealing rate of the gold wire are controlled for annealing; S4 post-processing: after the annealing is completed, the obtained gold wire is wound and collected and the finished product is inspected to ensure that the surface is smooth and undamaged, so as to obtain the gold alloy bonding wire.

5. The method for preparing the gold alloy bonding wire according to claim 4, characterized in that: The specific steps of the S1 melting and casting are as follows: (1) Au, Cu, Pt, Pd and part of Ag are melted in a melting furnace, the protective gas is argon, the melting temperature is 1200-1400°C, and the time is 25-40 minutes. After the melting is completed and cooled, an alloy ingot is obtained, and the alloy ingot is processed into an alloy cube. Then, the remaining Ag block is taken, and the remaining metal raw material is injected into the center of the Ag block, and then kneaded into an Ag cube of the same size as the alloy ingot; (2) Subsequently, the Ag cube and the alloy cube are stacked into a combination, with the Ag cube located in the center and surrounded by the alloy cube, and placed in a high vacuum continuous casting machine for melting under high-purity argon. After complete melting, it is stirred evenly and cast into an alloy column.

6. The method for preparing the gold alloy bonding wire according to claim 5, characterized in that: The smelting temperature of the high vacuum continuous casting machine is 1400-1500° C.; the smelting time of the high vacuum continuous casting machine is 30-50 minutes.

7. The method for preparing the gold alloy bonding wire according to claim 6, characterized in that: The specific steps of the S2 wire drawing are as follows: (1) pre-drawing the alloy column material, controlling the processing deformation amount, and obtaining a pre-drawn section bonding wire; (2) coarse drawing the pre-drawn bonding wire, heating it to 120-140°C, controlling the processing deformation amount, and obtaining a coarse-drawn bonding wire; (3) fine drawing the coarse-drawn bonding wire, heating it to 150-160°C, controlling the processing deformation amount, and obtaining a fine-drawn bonding wire; (4) ultra-fine drawing the fine-drawn bonding wire, heating it to 180-200°C, controlling the processing deformation amount, and obtaining an ultra-fine bonding wire.

8. The method for preparing the gold alloy bonding wire according to claim 7, characterized in that: The processing deformation of the pre-drawn wire is 15-20%; the processing deformation of the coarse drawn wire is 10-12%; the processing deformation of the fine drawn wire is 5-8%; and the processing deformation of the ultra-fine drawn wire is 2-4%.

9. The method for preparing the gold alloy bonding wire according to claim 8, characterized in that: The diameter of the ultra-fine bonding wire is 20-25 μm.

10. The method for preparing the gold alloy bonding wire according to claim 9, characterized in that: The specific steps of the S3 annealing are as follows: using nitrogen as the annealing atmosphere, annealing the ultra-fine bonding wire twice in succession, the effective annealing length is 700-1000 mm, the annealing temperature is 700-1000° C., the annealing rate is 50-80 m / min, and naturally cools to room temperature after the two annealings are completed.