CN116005118A - Ultra-fine mixed high-gold wire and its vacuum magnetron sputtering gold plating process and production equipment - Google Patents

Abstract

The invention discloses an ultra-fine mixed high-gold wire and its vacuum magnetron sputtering gold plating process and production equipment. In the process of producing metal rods, the invention makes the gold, silver and palladium metal mix more uniform and adds trace rare earth elements through secondary melting and casting. It can refine the grain, improve the pullability of the wire, and solve many problems of gold and silver alloy wire in the market, uneven mixing of gold and silver, and poor pullability. The gold plating process of the present invention makes the product performance more stable, is more conducive to subsequent production and processing, and improves production efficiency; uses the vacuum magnetron sputtering gold plating process to plate gold on the surface of mixed high gold wires, saves metal materials, and reduces product costs compared with pure gold wires. Environmental pollution; the performance index of the mixed high-gold wire produced by the present invention is better than that of the bonding wire containing 80% gold in the market, and the cost of the bonding wire is greatly reduced compared with the pure gold wire. The wire produced by the gold-plating process of the invention has good and stable performance and meets the requirements in the high-end packaging field of semiconductors.

Description

Ultrafine mixed high gold wire and its vacuum magnetron sputtering gold plating process and production equipment

Technical Field

The invention relates to a high-gold wire for semiconductor packaging, in particular to an ultra-fine mixed high-gold wire and a vacuum magnetron sputtering gold plating process and production equipment thereof.

Background Art

Bonding wire is one of the key materials for semiconductor packaging. As the main connection material between the chip and the external circuit for signal transmission, it plays a role in current conduction between the chip and the external circuit. Wire bonding is a key link in its packaging process.

Gold bonding wire is a key lead material used to connect integrated circuits or transistor chips to lead frames. In recent years, with the rapid development of the semiconductor industry, the integration of integrated circuits has become increasingly higher, the thickness of circuit boards has become increasingly smaller, the number of electrodes on devices has become increasingly larger, the electrode spacing has become increasingly narrower, and the packaging density has become increasingly smaller. The gold bonding wire used as a lead is required to have ultra-fine, high-strength, low arc length, and very high arc stability. The gold bonding wires currently on the market are mainly 4N gold bonding wires (mass percentage of gold is ≥99.99%) and 2N gold bonding wires (mass percentage of gold is ≥99.0%). The high gold content in these alloys leads to high production costs. The gold-silver alloy wires on the market that contain 80% gold have uneven mixing of gold and silver alloys, poor pullability, and unstable performance. The gold wire in the bonding lead has strong corrosion resistance and high reliability, and is widely used in mid-to-high-end products in the electronic packaging industry. However, gold wire is expensive. In order to reduce packaging costs, various substitutes for pure gold wire have been launched on the market.

The original pure gold wire is too expensive, and the original electroplating alloy wire is mostly chemical electroplating that pollutes the environment. It is easy to slip, leak, electromigration and oxidation in packaging applications, resulting in expensive packaging products and unstable performance.

Summary of the invention

In view of the deficiencies in the prior art, the technical problem to be solved by the present invention is to provide an ultrafine mixed high-gold wire and a vacuum magnetron sputtering gold plating process and production equipment thereof. The vacuum magnetron sputtering gold plating process reduces the production cost of the mixed high-gold wire (also known as bonding wire) and improves the production efficiency of the mixed high-gold wire. The mixed high-gold wire produced by the production equipment of the present invention has good and stable performance, can replace pure gold wire, and can meet the quality requirements of the field of high-end semiconductor packaging.

In order to solve the above technical problems, the present invention is implemented by the following scheme: An ultra-fine mixed high-gold wire of the present invention comprises, by mass percentage:

Silver Ag 10%-15%;

Palladium Pd 1%-5%;

Trace rare earth elements 50-100ppm;

The balance is gold.

Furthermore, the trace rare earth elements include lanthanum, cerium, yttrium, praseodymium and neodymium.

The present invention discloses a vacuum magnetron sputtering gold plating process for ultrafine mixed high-gold wire, and the vacuum magnetron sputtering gold plating process comprises the following steps:

Step 1: Take three kinds of precious metal raw materials of gold, silver and palladium with a purity requirement of ≥99.999%, among which the mass of silver Ag accounts for 10%-15% of the total, the mass of palladium Pd accounts for 1%-5% of the total, trace rare earth elements account for 50-100ppm, and the rest of the raw materials are gold;

Step 2: gold is mixed with trace rare earth elements such as lanthanum, cerium, yttrium, praseodymium and neodymium, and a master alloy is prepared by a vacuum alloy furnace. During the preparation of the master alloy, the vacuum degree of the vacuum alloy furnace is greater than 0.001 Pa.

Step 3, twice melting and casting, the master alloy obtained in step 2 is twice melt-casted by a secondary melting and casting machine, and processed into a mixed gold metal rod wire blank with a diameter of d1mm, so that the master alloy forms a wire mother material;

Step 4: wire drawing: the mixed gold metal rod wire blank in step 3 is drawn by a single-mode wire drawing machine to form a first mixed high gold wire with a diameter of d2 mm;

Step 5, secondary wire drawing process: the first mixed high gold wire of d2mm in step 4 is drawn into the second mixed high gold wire of d3mm by a non-sliding multi-mode wire drawing machine;

Step 6, cleaning and intermediate annealing: the second mixed high gold wire in step 5 is pulled into a horizontal annealing furnace with a cleaning system for cleaning, and then intermediate annealing is performed after cleaning;

Step 7, vacuum magnetron sputtering gold plating: the mixed high gold wire after annealing in step 6 is pulled into the vacuum magnetron sputtering gold plating equipment, and the surface of the mixed high gold wire is plated with 3% to 5% gold by using the vacuum magnetron sputtering gold plating process in a vacuum furnace with a vacuum plating temperature of <0.001Pa;

Step 8, three-time wire drawing: the mixed high-gold wire vacuum plated in step 7 is drawn into a finished wire of d4mm by a non-slip multi-mode wire drawing machine;

Step nine, heat treatment: using a controllable wire-paying tension, the finished wire after three wire drawing in step eight is pulled into a horizontal continuous heat treatment furnace with an automatic wire-paying mechanism for stress relief and recrystallization heat treatment. During the stress relief and recrystallization heat treatment, the horizontal continuous heat treatment furnace is continuously filled with inert gas to protect the finished wire;

Step 10, rewinding: rewinding the finished wire after heat treatment in step 9.

Furthermore, d1>d2>d3>d4.

Furthermore, the d1 is 6-10, d2 is 0.5-1.2, d3 is 0.03-0.1, and d4 is 0.005-0.05.

Furthermore, in step nine, the heat treatment temperature is 500-700°C.

Furthermore, in step nine, the inert gas is nitrogen.

The production equipment of the ultra-fine mixed high gold wire of the present invention comprises a frame, and on the frame, from the feed end to the discharge end, the production equipment also comprises:

A tension-controlled pay-off system, through which multiple strands of the second mixed high-gold wire are tensioned and enter the next process;

A first cleaning mechanism is used to clean the plurality of second mixed high gold wires delivered by the tension-controllable pay-off system;

A vacuum system having a vacuum power unit;

A vacuum furnace heat treatment section, wherein the vacuum power unit is connected to the furnace chamber of the vacuum furnace heat treatment section through a negative pressure channel. After the vacuum power unit is working, the furnace chamber forms a vacuum chamber. The second mixed high-gold wire enters the vacuum furnace heat treatment section after being cleaned. The vacuum furnace heat treatment section performs heat treatment on the second mixed high-gold wire entering the vacuum furnace heat treatment section, so that the second mixed high-gold wire passing through the vacuum furnace heat treatment section is heated to 300-500° C. After being heated, the stress of the second mixed high-gold wire is eliminated and softened.

The vacuum furnace body magnetron sputtering gold plating section is located in the rear section of the furnace chamber. The second mixed high-gold wire enters the vacuum furnace body magnetron sputtering gold plating section after heat treatment. The vacuum furnace body magnetron sputtering gold plating section adopts a vacuum magnetron sputtering gold plating process to sputter gold the second mixed high-gold wire. The vacuum furnace body magnetron sputtering gold plating section controls the composition ratio of sputtering gold by controlling the intensity and frequency of the electron beam;

A second cleaning mechanism is installed on a frame outside the furnace cavity, and the second cleaning mechanism cleans the second mixed high gold wire after sputtering and gold plating;

A drying mechanism, comprising a heating dryer, for drying the cleaned second mixed high gold wire;

The wire taking-up system is arranged in the next process of the drying mechanism, and takes up the dried second mixed high gold wire to form a reel.

Furthermore, the tension-controllable pay-off system has four pay-off mechanisms.

Furthermore, the production equipment also includes an electronic control part, which controls the operation of a tension-controllable pay-off system, a first cleaning mechanism, a vacuum system, a vacuum furnace heat treatment section, a vacuum furnace magnetron sputtering gold plating section, a second cleaning mechanism, a drying mechanism, and a take-up system.

Compared with the prior art, the beneficial effects of the present invention are as follows: in the process of producing 8mm metal bars, the present invention can make the gold, silver and palladium metals more evenly mixed by secondary melting and casting, and the addition of trace rare earth elements can refine the grains and improve the drawability of the wire. It solves many problems of gold-silver alloy wires in the market, uneven gold-silver mixing, and poor drawability, making the product performance more stable, more conducive to subsequent production and processing, and greatly improving production efficiency; using the vacuum ion plating method, gold is plated on the surface of the mixed high-gold wire, saving metal materials, reducing product costs compared to pure gold wire, and no environmental pollution; the performance indicators of the mixed high-gold wire produced in this way are better than the bonding wire containing 80% gold in the market, and the cost of the bonding wire is greatly reduced compared to the pure gold wire. The production process of the present invention improves the production efficiency of the mixed high-gold wire, and the wire produced has very good and stable performance in use, which can replace pure gold wire to meet the requirements of the quality of bonding wires in the field of high-end semiconductor packaging.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a flow chart of steps 1 to 5 of the vacuum magnetron sputtering gold plating process of the present invention.

FIG. 2 is a flow chart of steps five to ten of the vacuum magnetron sputtering gold plating process of the present invention.

FIG. 3 is a structural diagram of the production equipment of the ultrafine mixed high gold wire of the present invention.

Markings in the attached drawings: a pay-off system 1 for controlling controllable tension, a first cleaning mechanism 2, a vacuum system 3, a vacuum furnace heat treatment section 4, a vacuum furnace magnetron sputtering gold plating section 5, a second cleaning mechanism 6, a drying mechanism 7, a take-up system 8, and an electronic control part 9.

DETAILED DESCRIPTION

The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention, so that the advantages and features of the present invention can be more easily understood by those skilled in the art, thereby making a clearer and more explicit definition of the protection scope of the present invention. Obviously, the embodiments described in the present invention are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments in the present invention, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present invention.

In addition, the technical features involved in the different embodiments of the present invention described below can be combined with each other as long as they do not conflict with each other.

Embodiment 1: The specific structure of the present invention is as follows:

The ultra-fine mixed high-gold wire of the present invention comprises, by mass percentage:

Silver Ag 10%-15%;

Palladium Pd 1%-5%;

Trace rare earth elements 50-100ppm;

The balance is gold.

A preferred technical solution of this embodiment: the trace rare earth elements include lanthanum, cerium, yttrium, praseodymium, and neodymium.

Embodiment 2:

The vacuum magnetron sputtering gold plating process of the ultrafine mixed high gold wire of the present invention comprises the following steps:

Step 1: Take three kinds of precious metal raw materials, namely gold, silver and palladium, with a purity requirement of ≥99.999%, of which the mass of silver Ag accounts for 10%-15% of the total, the mass of palladium Pd accounts for 1%-5% of the total, trace rare earth elements account for 50-100ppm, and the rest of the raw materials are gold; high-purity metal raw materials ensure the final quality of the product and stable performance;

Step 2: Mix gold with trace rare earth elements such as lanthanum, cerium, yttrium, praseodymium and neodymium, and make a master alloy by a vacuum alloy furnace. During the process of making the master alloy, the vacuum degree of the vacuum alloy furnace is >0.001Pa; the master alloy is made under high vacuum so that the easily oxidizable rare earth elements will not be oxidized, and the grain structure of the mixed high gold wire is further refined;

Step 3, twice melting and casting, the master alloy obtained in step 2 is twice melt-casted by a secondary melting and casting machine, and processed into a mixed gold metal rod wire blank with a diameter of 8 mm, so that the master alloy forms a wire mother material;

Step 4: Wire drawing: The mixed gold metal rod wire blank in step 3 is drawn by a single-die wire drawing machine to form a first mixed high gold wire with a diameter of 1 mm, and the secondary melting and casting can obtain a mother wire material with more uniform composition;

Step 5, secondary wire drawing: The 1mm first mixed high gold wire in step 4 is drawn into a 0.05mm second mixed high gold wire through a non-slip multi-mode wire drawing machine; the non-slip wire drawing machine is the most advanced wire drawing machine in the industry, which can ensure the excellent surface quality of the wire drawing and can draw the wire to ultra-fine and ultra-long, and the wire drawing process is unbroken;

Step 6, cleaning and intermediate annealing: the second mixed high gold wire in step 5 is pulled into a horizontal annealing furnace with a cleaning system for cleaning, and then intermediate annealing is performed after cleaning;

Step 7, vacuum magnetron sputtering gold plating: the mixed high gold wire after annealing in step 6 is pulled into the vacuum magnetron sputtering gold plating equipment, and the surface of the mixed high gold wire is plated with 3% to 5% gold by using the vacuum magnetron sputtering gold plating process in a vacuum furnace with a vacuum plating temperature of <0.001Pa;

Step 8, three-time wire drawing: the mixed high-gold wire after vacuum plating in step 7 is drawn into a finished wire of 0.01 mm through a non-slip multi-mode wire drawing machine, and the wire drawing speed is 800-1000 m/min;

Step nine, heat treatment: using a controllable wire-paying tension, the finished wire after three wire drawing in step eight is pulled into a horizontal continuous heat treatment furnace with an automatic wire-paying mechanism for stress relief and recrystallization heat treatment. During the stress relief and recrystallization heat treatment, the horizontal continuous heat treatment furnace is continuously filled with inert gas to protect the finished wire;

Step 10, rewinding: rewinding the finished wire after heat treatment in step 9.

A preferred technical solution of this embodiment: d1>d2>d3>d4.

A preferred technical solution of this embodiment is: d1 is 6-10, d2 is 0.5-1.2, d3 is 0.03-0.1, d4 is 0.005-0.05, and d4 is 0.01. The ultra-fine range of high gold wire in this field is the size of d4.

A preferred technical solution of this embodiment: in step nine, the heat treatment temperature is 500-700°C.

A preferred technical solution of this embodiment: in step nine, the inert gas is nitrogen.

Embodiment 3:

The vacuum magnetron sputtering gold plating process of the ultrafine mixed high gold wire of the present invention specifically comprises the following processes:

(1) Weighing raw materials: weighing 750.3 g of pure gold with a purity of ≥99.999%, 91.5 g of silver with a purity of ≥99.999%, 45.75 g of palladium with a purity of ≥99.999%, and an appropriate proportion of rare earth master alloy;

(2) Melting and casting: The weighed gold and silver are subjected to medium frequency heating, the furnace temperature is set to 1300°C, the vacuum degree is ≤0.001pa, the refining time is 30 minutes, the cooling water pressure is 0.4Mpa, the cooling water flow rate is 10LPM, the first continuous casting speed is 100mm/min, the second continuous casting speed is 70mm/min, and the diameter of the formed wire billet is 8mm;

(3) Wire drawing: First use a single-mode wire drawing machine to draw the 8 mm wire blank to 1 mm, and then use a non-slip multi-mode wire drawing machine to draw the wire to a diameter of 0.05 mm;

(4) Cleaning and intermediate annealing: annealing of 0.05 mm bonding wire in a horizontal annealing furnace with a set temperature of 600 degrees, cleaned and filled with nitrogen protection, and an annealing speed of 60 mpm;

(5) Gold plating: using vacuum magnetron sputtering gold plating process, in a vacuum furnace with a vacuum degree of 0.01 Pa, a 0.05 mm gold-silver alloy wire is plated with 0.0005 to 0.001 mm of gold, and the wire-receiving speed is controlled so that the mass percentage of gold plating in any section is 3% ± 0.5;

(6) Secondary wire drawing: Use a multi-mode non-slip wire drawing machine to draw the wire to a finished product diameter of 0.010 mm, and control the wire drawing speed to 800 m/min;

(7) Heat treatment: Use a horizontal continuous heat treatment furnace with controllable pay-off tension and automatic pay-off to perform stress relief and recrystallization heat treatment on the finished wire, which requires inert gas nitrogen protection; the heat treatment temperature is 500°C and the annealing speed is 60 mpm;

(8) Rewinding: The heat-treated bonding wire is rewound into a 500m reel of finished product according to customer requirements.

Table 1: Comparison of the composition of the primary and secondary castings in Example 3

It can be clearly seen from the table that the deviation of the secondary casting is much smaller than that of the primary casting, and the mixed high-gold alloy rods after secondary casting are more uniform.

Embodiment 4:

(1) Weighing raw materials: weighing 960 g of pure gold with a purity of ≥99.999%, 120 g of silver with a purity of ≥99.999%, 43.64 g of palladium with a purity of ≥99.999%, and an appropriate proportion of rare earth master alloy;

(2) Melting and casting: The weighed gold and silver are subjected to medium frequency heating, the furnace temperature is set to 1300°C, the vacuum degree is ≤0.001pa, the refining time is 30 minutes, the cooling water pressure is 0.4Mpa, the cooling water flow rate is 10LPM, the first continuous casting speed is 100mm/min, the second continuous casting speed is 70mm/min, and the diameter of the formed wire billet is 8mm;

(3) Wire drawing: First use a single-mode wire drawing machine to draw the 8mm wire billet to 1mm, and then use a non-slip multi-mode wire drawing machine to draw the wire to a diameter of 0.05mm

(4) Cleaning and intermediate annealing: annealing of 0.05 mm bonding wire in a horizontal annealing furnace with a set temperature of 600 degrees, cleaned and filled with nitrogen protection, and an annealing speed of 60 mpm;

(5) Gold plating: vacuum ion plating is used to plate 0.0005 to 0.001 mm of gold on a 0.05 mm gold-silver alloy wire in a vacuum furnace with a vacuum degree of 0.01 Pa. The wire-winding speed is controlled so that the gold plating mass percentage is approximately 5% ± 0.5.

(6) Secondary wire drawing: Use a multi-mode wire drawing machine to draw the wire to a finished product diameter of 0.010 mm, and control the wire drawing speed to 800 m/min;

(7) Heat treatment: Use a horizontal continuous heat treatment furnace with controllable pay-off tension and automatic pay-off to perform stress relief and recrystallization heat treatment on the finished wire, which requires inert gas nitrogen protection; the heat treatment temperature is 700°C and the annealing speed is 60 mpm;

(8) Rewinding: The heat-treated bonding wire is rewound into a 500m reel of finished product according to customer requirements.

Embodiment 5:

(1) Weighing raw materials: weighing 810 g of pure gold with a purity of ≥99.999%, 100 g of silver with a purity of ≥99.999%, 25 g of palladium with a purity of ≥99.999%, and an appropriate proportion of rare earth master alloy;

(2) Melting and casting: The weighed gold and silver are subjected to medium frequency heating, the furnace temperature is set to 1300°C, the vacuum degree is ≤0.001pa, the refining time is 30 minutes, the cooling water pressure is 0.4Mpa, the cooling water flow rate is 10LPM, the first continuous casting speed is 100mm/min, the second continuous casting speed is 70mm/min, and the diameter of the formed wire billet is 8mm;

(3) Wire drawing: First use a single-mode wire drawing machine to draw the 8mm wire billet to 1mm, and then use a non-slip multi-mode wire drawing machine to draw the wire to a diameter of 0.05mm

(4) Cleaning and intermediate annealing: annealing of 0.05 mm bonding wire in a horizontal annealing furnace with a set temperature of 600 degrees, cleaned and filled with nitrogen protection, and an annealing speed of 60 mpm;

(5) Gold plating: vacuum ion plating is used to plate 0.0005 to 0.001 mm of gold on a 0.05 mm gold-silver alloy wire in a vacuum furnace with a vacuum degree of 0.01 Pa. The wire-winding speed is controlled to achieve a gold plating mass percentage of approximately 4% ± 0.5.

(6) Secondary wire drawing, using a multi-mode wire drawing machine to draw the wire to a finished product diameter of 0.010 mm, and controlling the wire drawing speed to 1000 m/min;

(7) Heat treatment: Use a horizontal continuous heat treatment furnace with controllable pay-off tension and automatic pay-off to perform stress relief and recrystallization heat treatment on the finished wire. Inert gas nitrogen protection is required. The heat treatment temperature is 650°C and the annealing speed is 60 mpm.

(8) Rewinding: The heat-treated bonding wire is rewound into a 500m reel of finished product according to customer requirements.

Table 2: Comparison of component tests of Example 3, Example 4 and Example 5

project Gold Silver Palladium Pd Example 3 ≈85% ≈10% ≈5% Example 4 ≈85% ≈11% ≈4% Example 5 ≈85% ≈12% ≈3%

Table 3 is a comparison table of technical data of 0.025mm (1mil) 4N gold wire, Example 3, Example 4, and Example 5

It can be seen from the above table that the mixed high-gold wire product manufactured by the present invention contains 85%±1 gold, and its mechanical and electrical properties are better than those of pure gold wire. It has moderate hardness and fine grains, and can replace pure gold wire for IC packaging, which greatly reduces the cost of materials and meets the requirements of the semiconductor high-end packaging field for bonding wire quality.

Embodiment 6:

The production equipment of the ultra-fine mixed high gold wire of the present invention comprises a frame, and on the frame, from the feed end to the discharge end, the production equipment also comprises:

A tension-controllable pay-off system 1, wherein multiple strands of the second mixed high-gold wire are tensioned through the tension-controllable pay-off system 1 and enter the next process;

A first cleaning mechanism 2 is used to clean the multiple strands of second mixed high gold wires delivered by the tension-controllable pay-off system 1;

A vacuum system 3, having a vacuum power unit;

The vacuum furnace body heat treatment section 4, the vacuum power unit is connected to the furnace cavity of the vacuum furnace body heat treatment section 4 through a negative pressure channel. After the vacuum power unit is working, the furnace cavity forms a vacuum cavity. The second mixed high gold wire enters the vacuum furnace body heat treatment section 4 after being cleaned. The vacuum furnace body heat treatment section 4 performs heat treatment on the second mixed high gold wire entering, so that the second mixed high gold wire passing through the vacuum furnace body heat treatment section 4 is heated to 300-500°C. After being heated, the stress of the second mixed high gold wire is eliminated and softened;

The vacuum furnace body magnetron sputtering gold-plating section 5 is located in the rear section of the furnace chamber. The second mixed high-gold wire enters the vacuum furnace body magnetron sputtering gold-plating section 5 after heat treatment. The vacuum furnace body magnetron sputtering gold-plating section 5 adopts a vacuum magnetron sputtering gold-plating process to sputter gold-plating the second mixed high-gold wire. The vacuum furnace body magnetron sputtering gold-plating section 5 controls the composition ratio of sputtering gold by controlling the intensity and frequency of the electron beam;

A second cleaning mechanism 6 is installed on a frame outside the furnace cavity, and the second cleaning mechanism 6 cleans the second mixed high gold wire after sputtering and gold plating;

A drying mechanism 7, comprising a heating dryer, for drying the cleaned second mixed high gold wire;

The wire taking-up system 8 is provided in the next process of the drying mechanism 7, and takes up the dried second mixed high gold wire to form a reel.

A preferred technical solution of this embodiment: the tension-controllable wire-paying system has four wire-paying mechanisms.

A preferred technical solution of this embodiment: the production equipment also includes an electronic control part 9, which controls the operation of a tension-controllable pay-off system 1, a first cleaning mechanism 2, a vacuum system 3, a vacuum furnace body heat treatment section 4, a vacuum furnace body magnetron sputtering gold plating section 5, a second cleaning mechanism 6, a drying mechanism 7, and a take-up system 8.

In summary, in the process of producing 8mm metal bars, the present invention uses secondary melting and casting to make the gold, silver and palladium metals more evenly mixed, and the addition of rare earth vector elements can refine the grains and improve the drawability of the wire. It solves many problems of gold-silver alloy wires in the market, such as uneven mixing of gold and silver, and poor drawability, making the product performance more stable, more conducive to subsequent production and processing, and greatly improving production efficiency; using the vacuum ion plating method, the surface of the mixed high-gold wire is plated with gold, saving metal materials, reducing product costs relative to pure gold wire, and no environmental pollution; the performance indicators of the mixed high-gold wire produced in this way are better than the bonding wire containing 80% gold in the market, and the cost of the bonding wire is greatly reduced compared to pure gold wire. The production process of the present invention improves the production efficiency of the mixed high-gold wire, and the wire produced has very good and stable performance in use, which can replace pure gold wire to meet the requirements of the quality of bonding wires in the field of high-end semiconductor packaging.

The above description is only a preferred embodiment of the present invention, and does not limit the patent scope of the present invention. Any equivalent structure or equivalent process transformation made by using the contents of the present invention specification and drawings, or directly or indirectly applied in other related technical fields, are also included in the patent protection scope of the present invention.

Claims (10)

1. An ultra-fine mix Gao Jinsi comprising, in mass percent:

10% -15% of silver Ag;

1% -5% of palladium Pd;

50-100ppm of trace rare earth elements;

the balance of gold.

2. The ultra-fine blend Gao Jinsi of claim 1, wherein said trace rare earth elements comprise lanthanum, cerium, yttrium, praseodymium, neodymium.

3. The vacuum magnetron sputtering gold plating process of the superfine mixed Gao Jinsi is characterized by comprising the following steps of:

firstly, taking three noble metal raw materials with purity requirements of more than or equal to 99.999 percent, wherein the mass of silver Ag occupies 10 to 15 percent of the total amount, the mass of palladium Pd occupies 1 to 5 percent of the total amount, the trace rare earth elements are 50 to 100ppm, and the rest raw materials are gold;

step two, mixing gold with trace rare earth elements of lanthanum, cerium, yttrium, praseodymium and neodymium, and preparing master alloy by a vacuum alloy furnace, wherein the vacuum degree of the vacuum alloy furnace is more than 0.001Pa in the process of preparing the master alloy;

step three, secondary casting, namely, secondary casting the master alloy prepared in the step two through a secondary casting machine, and processing the master alloy into a mixed gold metal bar wire blank with the diameter of d1mm, so that the master alloy forms a wire parent metal;

step four, wiredrawing treatment: drawing the mixed gold metal bar wire blank in the third step through a single-die drawing machine to form a first mixed high gold wire with the diameter of d2 mm;

step five, secondary wiredrawing treatment: pulling the first mixed high gold wire with d2mm in the fourth step to a second mixed Gao Jinsi with d3mm through a sliding-free multi-die wire drawing machine;

step six, cleaning and intermediate annealing: pulling the second mixture Gao Jinsi in the step five to a horizontal annealing furnace with a cleaning system for cleaning, and carrying out intermediate annealing after cleaning;

seventh, gold plating by vacuum magnetron sputtering: the annealed mixture Gao Jinsi in the step six is drawn to a vacuum magnetron sputtering gold plating device, and 3 to 5 percent of gold is plated on the surface of the mixture Gao Jinsi by adopting a vacuum magnetron sputtering gold plating process in a vacuum furnace with vacuum plating of less than 0.001Pa;

step eight, three wiredrawing: pulling the mixture Gao Jinsi subjected to vacuum plating in the step seven to a finished wire rod with d4mm through a sliding-free multi-die wire drawing machine;

step nine, heat treatment: drawing the finished wire rod subjected to three-time wire drawing in the eighth step to a horizontal continuous heat treatment furnace with an automatic wire drawing mechanism by using controllable wire drawing tension, carrying out stress-relief recrystallization heat treatment, and continuously filling inert gas into the horizontal continuous heat treatment furnace to protect the finished wire rod in the stress-relief recrystallization heat treatment process;

step ten, rewinding: and (3) rewinding the finished wire after the heat treatment in the step nine.

4. The vacuum magnetron sputtering gold plating process according to claim 3, wherein d1 & gt d2 & gt d3 & gt d4.

5. The vacuum magnetron sputtering gold plating process according to claim 4, wherein d1 is 6-10, d2 is 0.5-1.2, d3 is 0.03-0.1, and d4 is 0.005-0.05.

6. A vacuum magnetron sputtering gold plating process according to claim 3 wherein in step nine, the heat treatment temperature is 500-700 ℃.

7. A vacuum magnetron sputtering gold plating process according to claim 3 wherein in step nine, the inert gas is nitrogen.

8. The production equipment of superfine mixed high-gold wire comprises a frame, and is characterized in that in the frame, from a feeding end to a discharging end, the production equipment further comprises:

a tension-controllable paying-off system (1), wherein a plurality of strands of second mixtures Gao Jinsi form a tensioning state through the tension-controllable paying-off system (1) and enter the next working procedure;

a first cleaning mechanism (2) for cleaning a plurality of second mixtures Gao Jinsi sent out by the tension-controllable paying-off system (1);

a vacuum system (3) having a vacuum power unit;

the vacuum furnace body heat treatment section (4), the vacuum power unit is connected with a furnace chamber of the vacuum furnace body heat treatment section (4) through a negative pressure channel, after the vacuum power unit works, the furnace chamber forms a vacuum cavity, the second mixture Gao Jinsi enters the vacuum furnace body heat treatment section (4) after being cleaned, the vacuum furnace body heat treatment section (4) carries out heat treatment on the entered second mixture Gao Jinsi, so that the second mixture Gao Jinsi passing through the vacuum furnace body heat treatment section (4) is heated to 300-500 ℃, and the second mixture Gao Jinsi is subjected to stress relief and softening after being heated;

the vacuum furnace body magnetron sputtering gold plating section (5) is positioned at the rear section of the furnace chamber, the second mixture Gao Jinsi enters the vacuum furnace body magnetron sputtering gold plating section (5) after being subjected to heat treatment, the vacuum furnace body magnetron sputtering gold plating section (5) adopts a vacuum magnetron sputtering gold plating process to sputter gold plating the second mixture Gao Jinsi, and the vacuum furnace body magnetron sputtering gold plating section (5) controls the component proportion of sputtering gold plating by controlling the intensity and the frequency of an electron beam;

a second cleaning mechanism (6) which is arranged on the frame outside the furnace chamber, wherein the second cleaning mechanism (6) cleans the second mixture Gao Jinsi after sputtering and gold plating;

a drying mechanism (7) provided with a heating dryer for drying the cleaned second mixture Gao Jinsi;

and a winding system (8) which is arranged at the next step of the drying mechanism (7) and winds the dried second mixture Gao Jinsi into a reel.

9. The apparatus for producing ultra-fine mixed high-gold wire according to claim 8, wherein the tension-controllable paying-off system has 4 paying-off mechanisms.

10. The production equipment of the superfine mixed high-gold wire according to claim 8, further comprising an electric control part (9), wherein the electric control part (9) controls the operation of the pay-off system (1), the first cleaning mechanism (2), the vacuum system (3), the vacuum furnace body heat treatment section (4), the vacuum furnace body magnetron sputtering gold plating section (5), the second cleaning mechanism (6), the drying mechanism (7) and the wire collecting system (8) with controllable tension.

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