KR102214366B1 - Silver alloy copper wire - Google Patents

Abstract

A silver alloy copper wire comprising a wire core is provided, the wire core itself comprising (a) silver in an amount of 0.3 to 0.7% by weight, (b) copper in an amount in the range of 99.25 to 99.7% by weight, and (c) 0 to 500 Consisting of additional components in ppm by weight, all amounts in ppm by weight and ppm by weight are based on the total weight of the core.

Description

Silver alloy copper wire

The present invention relates to a silver alloy copper wire having a thickness of 8 to 80 μm comprising a core containing copper and silver in a specific weight ratio. The invention also relates to a method of making such a wire.

The use of bonding wires in electronic and microelectronic applications is a well-known state of the art. Although bonding wires were initially made of gold, nowadays less expensive materials such as copper, copper alloys, silver and silver alloys are used.

Regarding the wire shape, bonding wires with circular cross-sections and bonding ribbons with more or less rectangular cross-sections are the most common. These two types of wire shapes each have their own advantages that make them useful for special applications.

It is an object of the present invention to provide a silver alloy copper wire suitable for use in wire bonding applications, which silver alloy copper wire in particular has improved corrosion resistance and bonding performance, but for example excellent reliability performance, ultra fine pitch requirements. It also exhibits an overall balanced attribute spectrum suitable for wire bonding applications including improved bonding ball shape to meet, improved second bond window, improved looping performance, extended floor life, and the like.

The contribution to the solution of this object is provided by the subject of the category-forming claim. The dependent claims of the categorical claims represent preferred embodiments of the present invention, the subject of which also constitutes a contribution to solve the above object.

In a first aspect, the present invention relates to a silver alloy copper wire comprising a wire core (hereinafter referred to simply as “core”) or consisting only of a core, the wire core itself consisting of the following components:

(a) 0.3 to 0.7% by weight (weight-%,% by weight), preferably silver in an amount of 0.5% by weight,

(b) copper in an amount ranging from 99.25 to 99.7% by weight, preferably 99.45 to 99.5% by weight, more preferably 99.49 to 99.5% by weight, and

(c) 0 to 500 ppm by weight (weight-ppm, ppm by weight), preferably 0 to 100 ppm by weight of additional components (components other than silver and copper).

All amounts of weight percent and ppm weight here are based on the total weight of the core.

The table below shows various embodiments of the silver alloy copper wire core composition.

Copper (% by weight) Silver (% by weight) Additional ingredients (ppm by weight) Total weight ratio (% by weight) 99.25~99.7 0.3~0.7 0~500 100.00 99.29~99.7 0.3~0.7 0~100 100.00 99.45~99.5 0.5 0~500 100.00 99.49~99.5 0.5 0~100 100.00

The silver alloy copper wire is preferably a bonding wire for bonding in microelectronics. The silver alloy copper wire is preferably a one-piece object. Several shapes are known and appear to be useful for the silver alloy copper wire of the present invention. In the present invention, the term "bonding wire" includes all shaped cross sections and all useful wire diameters, but bonding wires having circular cross sections and thin diameters are preferred. The average cross section is, for example, in the range of 50 to 5024 μm ² or preferably 110 to 2400 μm ² ; Therefore, in the case of a preferred circular cross section, the average diameter is, for example, in the range of 8 to 80 μm or preferably 12 to 55 μm.

The average diameter, or simply the diameter of the wire or wire core, can be obtained by the "sizing method". According to this method, the physical weight of a silver alloy copper wire of a specified length is determined. Based on this weight, the diameter of the wire or wire core is calculated using the concentration of the wire material. The diameter is calculated as the arithmetic mean of 5 measurements for 5 cuts of a particular wire.

As described above, the wire core contains (a) silver and (b) copper in the aforementioned ratio. However, the core of the silver alloy copper wire of the present invention may include additional components in a total amount of (c) 0 to 500 ppm by weight, preferably 0 to 100 ppm by weight. In this context, these additional components, sometimes referred to as “necessary impurities”, are small amounts of chemical elements and/or compounds originating from impurities present in the raw materials used or from the wire manufacturing process. That is, the presence of an additional component of the type (c) may originate from impurities present in silver and/or copper, for example. Examples of such additional components are Au, P, Ni, Pd, Fe, Si, Mn, Cr, Ce, Mg, La, Al, B, Zr, Ti, S, and the like. A low total amount of 0 to 500 ppm by weight or even 0 to 100 ppm by weight of the additional component (c) ensures good reproducibility of the wire properties. The additional component (c) present in the core is generally not added separately.

In one embodiment, the core of the silver alloy copper wire of the present invention comprises less than 15 ppm by weight of each additional component (c) as follows: Au, P, Ni, Pd, Fe, Si, Mn, Cr, Ce, Mg, La, Al, B, Zr, Ti, S.

In this context the core of the silver alloy copper wire is defined as a homogeneous bulk material area. Since any bulk material always has a surface area that exhibits some different properties, the nature of the core of the wire is understood as a property of a homogeneous bulk material area. The surface of the bulk material region may differ in shape, composition (eg, chlorine and/or oxygen component) and other characteristics. The surface may be the outer surface of the wire core; In such an embodiment, the silver alloy copper wire of the present invention is composed of a wire core. In an alternative embodiment, the surface may be an interface area between the wire core and the coating layer overlaid on the wire core.

In the context of the present invention the term "overlap" is used to describe the relative position of a first item, for example a wire core, in relation to a second item, for example a coating layer. "Overlapping" is not necessarily characterized in that an additional item, such as an intermediate layer, can be placed between the first item and the second item. Preferably, the second item overlaps the first item at least partially, for example at least 30%, 50%, 70% or 90% respectively with respect to the entire surface of the first item. Most preferably the second item completely overlaps the first item.

The term “intermediate layer” in the context of the present invention refers to the region of the silver alloy copper wire between the core and the coating layer overlaid on the core. In this area there is a combination of the materials of the core and the coating layer.

In the context of the present invention the term "thickness" is used to define the size of a layer in a direction perpendicular to the longitudinal axis of the core, which layer at least partially overlaps the surface of the core.

In one embodiment, the core has a surface and the coating layer overlies the surface of the core.

In one embodiment, the mass of the coating layer is 5% by weight or less, preferably 2% by weight or less, respectively, with respect to the total mass of the core. When there is a coating layer, the coating layer often has a minimum mass of at least 0.1% by weight or at least 0.5% by weight, respectively, with respect to the total mass of the core. The application of a small amount of material as a coating layer preserves the properties defined by the material of the core of the wire. On the other hand, the coating layer provides special properties to the wire surface, such as being inert to the environment, corrosion resistance, improved adhesion, and the like. For example, the thickness of the coating layer is in the range of 20 to 120 nm for a wire having a diameter of 18 μm. In the case of a wire having a diameter of 25 μm, the coating layer may have a thickness in the range of 30 to 150 nm, for example.

In one embodiment, the coating layer may be composed of a noble metal element. The coating layer may be a single layer of one of the noble metal elements. In other embodiments, the coating layer may be a multilayer composed of a number of overlapping and adjacent sub-layers, with each sub-layer composed of a different precious metal element. Common techniques for depositing these precious metal elements on the core include plating such as electroplating and electroless plating, deposition of materials from gaseous phases such as sputtering, ion plating, vacuum deposition and physical vapor deposition, and deposition of materials from dissolved metals. to be.

In one embodiment, the silver alloy copper wire or core thereof of the present invention is characterized by at least one of the following intrinsic properties (see “Test Method A” below):

(i) the average wire particle size (average particle size) is less than 4.0 μm, for example in the range of 2 to 3 μm, as measured in the longitudinal direction (longitudinal direction of the wire core),

(ii) the ratio of the average particle size measured in the longitudinal direction and the diameter of the wire core is in the range of 0.05 to 0.25, preferably 0.1 to 0.20,

(iii) The standard deviation ratio (RSD) of the average particle size to the average particle size of the core as measured in the longitudinal direction is less than 0.3, for example in the range of 0.1 to 0.2.

The term "unique property" is used herein in connection with the wire core. Intrinsic attribute refers to the attribute that the wire core has intrinsically (independent of other elements). Foreign attributes as opposed to intrinsic attributes depend on the wire core relationship with other factors such as the measurement method and/or measurement conditions used.

In another aspect, the invention also relates to a process for making silver alloy copper wires in any of the embodiments described above. The manufacturing process includes at least the following steps:

(1) (a) Silver in an amount of 0.3 to 0.7 wt%, preferably 0.5 wt%, (b) 99.25 to 99.7 wt%, preferably 99.45 to 99.5 wt%, more preferably 99.49 to 99.5 wt% A precursor consisting of copper in amounts in the range, and (c) 0 to 500 ppm by weight, preferably 0 to 100 ppm by weight, of additional components, wherein all amounts in weight percent and ppm by weight are based on the total weight of the precursor item. Preparing an item;

(2) stretching the precursor item to form a wire precursor until a desired final diameter of the wire core is obtained; And

(3) In order to form a silver alloy copper wire, the wire precursor obtained after completion of the process step (2) is finally strand annealed at an oven set temperature in the range of 600 to 680°C for an exposure time in the range of 0.1 to 3 seconds. step.

The term "strand annealing" is used herein. Strand annealing is a continuous process that enables high-speed production of wires with high reproducibility. Strand annealing means that annealing is performed dynamically while the wire precursor item to be annealed or the wire precursor to be annealed moves through the annealing oven and is wound on a reel after leaving the annealing oven.

The term "oven set temperature" is used herein. This means a fixed temperature in the temperature controller of the annealing oven. Strand annealing is typically carried out in a tubular annealing oven.

The present disclosure distinguishes between precursor items, wire precursors and silver alloy copper wires. The term “precursor item” is used for a wire shear that has not reached the desired final diameter of the wire core, and the term “wire precursor” is used for a wire shear that has reached the desired final diameter. After completion of the process step (3), that is, after the final strand annealing of the wire precursor of the desired final diameter, a silver alloy copper wire in the sense of the invention is obtained.

The precursor item prepared in process step (1) can be obtained by alloying/doping copper with a desired amount of silver. The copper alloy itself can be prepared by conventional processes known in the field of metal alloys, for example by dissolving copper and silver together in a desired ratio. In doing so, you can use the master alloy. The dissolution process can be carried out, for example, using an induction furnace, and it is advantageous to work in a vacuum or inert gas atmosphere. The materials used may have a purity of at least 99.99% by weight, for example. The molten metal thus produced can be cooled to form a homogeneous piece of the copper-based precursor item. Typically, such a precursor item may be in the form of a rod having a diameter of, for example, 2 to 25 mm and a length of, for example, 5 to 100 m. Such rods can be produced by casting the copper alloy molten metal in a suitable mold at room temperature, followed by cooling and solidification.

If a single-layer or multi-layered coating layer is on the core of the silver alloy copper wire as described in connection with some embodiments of the first aspect of the present invention, the coating layer is not yet elongated, finally unstretched or the desired final diameter. It is preferred to apply to wire precursor items that are not fully stretched to. Those skilled in the art will know how to calculate the thickness of this coating layer in the precursor item after stretching the precursor item with the coating layer to obtain a coating layer of the thickness described for the embodiment of the wire, ie to form a wire precursor. As already described above, various techniques are known for forming a coating layer of a material according to an embodiment on a surface of a copper alloy. Preferred techniques are plating such as electroplating and electroless plating, deposition of materials from a gaseous phase such as sputtering, ion plating, vacuum deposition and physical vapor deposition, and deposition of materials from molten metals.

In order to superimpose the metal coating as a single layer or multiple layers on the wire core as described for some embodiments of the first aspect of the invention, it is advantageous to stop process step (2) when the desired diameter of the precursor item has been reached. Such a diameter may for example be in the range of 80 to 200 μm. A single or multilayer metallic coating can then be applied, for example by one or more electroplating process steps. Then process step (2) continues until the desired final diameter of the wire core is obtained.

In process step (2), the precursor item is stretched until the desired final diameter of the wire core is obtained to form the wire precursor. Techniques for stretching a precursor item to form a wire precursor are known and appear to be useful in the context of the invention. Preferred techniques are rolling, swaging, die drawing, and the like, of which die drawing is particularly good. In the latter case, the precursor item is drawn in several process steps until the desired final diameter of the wire core is reached.

The desired final diameter of the wire core may be in the range of 8 to 80 μm or preferably in the range of 12 to 55 μm. Such wire die drawing processes are well known to those skilled in the art. Conventional tungsten carbide and diamond drawing dies can be used, and conventional drawing lubricants can be used to support drawing.

It is preferred that step (2) does not include any sub-steps of intermediate annealing.

In process step (3), the stretched wire precursor obtained after completion of process step (2) is finally strand annealed. The final strand annealing is for example carried out at an oven set temperature in the range of 600 to 680° C. for an exposure time of 0.1 to 3 seconds, or in a preferred embodiment of 610 to 650° C. for 0.1 to 1.5 seconds. In an exemplary embodiment, the final strand annealing may be performed at an oven set temperature of 630° C. for an exposure time of 0.85 seconds.

The final strand annealing is performed by pulling the elongated wire precursor with a defined temperature profile at a predetermined annealing rate through a conventional annealing oven, typically in the form of a cylindrical tube of a predetermined length, wherein the predetermined annealing rate is For example, it may be selected in the range of 10 to 60 m/min. In doing so, an annealing time/oven temperature parameter can be defined and set.

In a preferred embodiment, the finally strand annealed silver alloy copper wire is quenched in water, which in one embodiment may contain one or more additives, for example 0.01 to 0.07 vol.-% of additives. . Quenching in water is carried out immediately or rapidly, i.e. 0.2 to 0.6 seconds from the temperature received in the process step (3) of the finally strand annealed silver alloy copper wire to room temperature, for example by dipping or dripping. Means to cool within.

The final strand annealing of process step (3) can be carried out in an inert or reducing atmosphere. Many types of inert and reducing atmospheres are known in the art and are used to purging annealing ovens. Nitrogen or argon is preferred in a known inert atmosphere. Hydrogen is a good example in a known reducing atmosphere. Another preferred reducing atmosphere is a mixture of hydrogen and nitrogen. A good mixture of hydrogen and nitrogen is 90 to 98% by volume nitrogen and 2 to 10% by volume hydrogen, where the volume% is a total of 100% by volume. A good mixture of nitrogen/hydrogen is 93/7, 95/5 and 97/3 vol%/vol%, each based on the total volume of the mixture. If a part of the surface of the silver alloy copper wire is sensitive to oxidation by oxygen in the air, it is particularly preferable to apply a reducing atmosphere during annealing. Purging with an inert or reducing gas of this type is a gas exchange rate in the range of 10 to 125 minutes (min) ^-1 , more preferably 15 to 90 minutes ^-1 and most preferably 20 to 50 minutes ^-1 (= gas flow rate [Liter/min]: It is preferably carried out with the oven internal volume [liter]).

The unique combination of the composition of the precursor item material (same as the material of the finished silver alloy copper wire) and the annealing parameters prevailing during process step (3) is important to obtain a wire of the invention that exhibits at least one of the aforementioned intrinsic properties. I believe. The temperature/time conditions of the final strand annealing step enable the achievement or adjustment of the intrinsic properties of the silver alloy copper wire core. The better overall performance of the silver alloy copper wire of the present invention as compared to pure copper wire is a result of its composition and final strand annealing conditions; The two features together lead to a specific particle structure expressed as intrinsic properties (i) to (iii). This particular particle structure is responsible for good performance parameters. The grain structure differs from that of pure copper wire, especially by a smaller average grain size and a smaller grain size distribution.

After completion of the process step (3), the silver alloy copper wire of the present invention is completed. In order to fully benefit from the property, it is advantageous to use the property immediately for wire bonding applications, i.e. without delay, within a floor time of 10 days after completion of process step (3) for example. Alternatively, in order to maintain the broad wire bonding process window properties of the silver alloy copper wire and to protect the silver alloy copper wire from oxidation or other chemical attack, the finished wire is typically immediately after completion of process step (3). I.e. wound or vacuum sealed without delay, for example within 1 to 5 hours after completion of process step (3), and then stored for further use as a bonding wire. Storage under vacuum sealed conditions should not exceed 6 months. After opening the vacuum seal, the silver alloy copper wire should be used for wire bonding within 10 days.

All process steps (1) to (3) as well as winding and vacuum sealing are preferably carried out in clean room conditions (US FED STD 209E clean room standard, 1k standard).

A third aspect of the present invention is a silver alloy copper wire obtainable by the above-described process according to the second aspect of the invention or its embodiment. It has been found that the silver alloy copper wire is suitable for use as a bonding wire in wire bonding applications. Wire bonding techniques are well known to those skilled in the art. In the wire bonding process, a ball bond (first bond) and a stitch bond (second bond, wedge bond) are typically formed. During bond formation, a certain force (typically measured in grams) supported by the application of the scrub amplitude (typically measured in μm) or supported by the application of ultrasonic energy (typically measured in mA) Is authorized. In a wire bonding process, a mathematical product of the difference between the upper and lower limits of the applied force and the upper and lower limits of the applied scrub amplitude, or the difference between the upper and lower limits of the applied force and the upper and lower limits of the applied ultrasonic energy The mathematical product of the difference between defines the wire bonding process window: i.e.

(Upper limit of applied force-Lower limit of applied force) ㆍ (Upper limit of applied scrub amplitude-Lower limit of applied scrub amplitude) = Wire bonding process window.

or

(Upper limit of applied force-Lower limit of applied force) ㆍ (Upper limit of applied ultrasonic energy-Lower limit of applied ultrasonic energy) = Wire bonding process window.

The wire bonding process window is a force/scrub that allows the formation of a wire bond that conforms to specifications, i.e. passes conventional tests such as the conventional pulling test, ball shear test and ball pulling test to name a few. Defines the area of the amplitude combination or the force/ultrasonic energy combination.

In other words, the first bond (ball bond) process window area is the product of the difference between the upper and lower limits of the force used during bonding and the difference between the upper and lower limits of the applied scrub amplitude, or the upper and lower limits of the force used during bonding. It is the product of the difference between the difference between the two and the difference between the upper and lower limits of the applied ultrasonic energy, and the resulting bond is a predetermined ball shear test specification, e.g. 0.0085 g/µm ² ball shear, no comparative adhesion to the bond pad, etc. The second bond (stitch bond) process window area is the product of the difference between the upper and lower limits of the force used during bonding and the difference between the upper and lower limits of the applied scrub amplitude, or the upper and lower limits of the force used during bonding. It is the product of the difference between the lower limits and the difference between the upper and lower limits of the applied ultrasonic energy, and the resulting bond must meet certain pulling test specifications, e.g. 2.5 grams of pulling force, no non-adherence to lead, etc.

For industrial applications, it is desirable to have a wide wire bonding process window (force (g) versus scrub amplitude (µm) or force (g) versus ultrasonic energy (mA)) for reasons of wire bonding process robustness. The wires of the present invention exhibit a fairly wide wire bonding process window.

The following non-limiting examples illustrate the invention. These examples serve as illustrative descriptions of the invention and are not intended to in any way limit the scope of the invention or the claims.

Example

Test methods A to D

All tests and measurements were conducted at T=20°C and relative humidity RH=50%.

A. Linear blocking method

First, the wire was potted using a cold mounting epoxy resin, and then polished (cross-sectioned) by a standard metallographic technique. A multi-prep semi-automatic polisher was used with low force and optimum speed to grind and polish the sample with minimal strain strain on the sample surface. Finally, the polished sample was chemically etched with ferric chloride to reveal the grain boundaries. The particle size was measured using a linear blocking method with an optical microscope having a magnification of 1000 according to ASTM E112-12 standard.

B. Ball shape

A free air ball (FAB) was formed using an electric flame-off (EFO) torch (in a nitrogen/hydrogen gas atmosphere of 95/5% by volume/% by volume, EFO current: 50mA, EFO time: 120µs). The formed FAB was lowered from a predefined height (the tip of 203.2 μm) to the bonding pad at a predefined rate (contact speed of 6.4 μm/sec). Upon contacting the bonding pad, a set of defined bonding parameters (100 g of adhesion, 95 mA of ultrasonic energy and 15 ms of adhesion time) were applied to deform the FAB and bond balls were formed. After forming the ball, the capillary was raised to a prescribed height (a kink height of 152.4 μm and a loop height of 254 μm) to form a loop. After forming the loop, the capillary was lowered to lead to form a stitch. After forming the stitch, the wire was cut to make a predefined tail length (extending the tail length of 254 μm), the capillary was raised and the wire clamp was closed. Five bonded wires for each sample were optically examined using a microscope with a magnification of 1000. Rating: + round, 0 acceptable,-flowery.

C. Off center ball (OCB)

The same method as described in Method B was applied, but instead of examining the roundness of the ball, the centrality of the ball was determined. Five bonded wires were optically inspected for each sample. Assessment: + centered, 0 acceptable decentralized,-decentralized.

D. Corrosion resistance:

The continuous casting 8mm rod was separated into 10mm lengths, immersed in a salt solution at 85°C for 4 days, washed with deionized (DI) water, and then washed with acetone. The salt solution contained 20% by weight NaCl dissolved in DI water. The surface discoloration of the rod was observed with a low power scope (stereoscopic-SZX16) with a magnification of 10 to 100X. The surface of the rod, which changed from the original copper pink to dark black, showed severe crevice corrosion. SEM-EDX on the dark black surface showed peaks of chlorine, oxygen and copper.

evaluation:

-, 100% cast rod surface changed from original copper pink to dark black, indicating severe crevice corrosion

0, less than 70% of the cast rod surface, which changed from original copper pink to black, indicating crevice corrosion

+, less than 40% of the cast rod surface, which changed from original copper pink to black, indicating weak crevice corrosion

++, less than 10% of the cast rod surface that changed from original copper pink to dark black, indicating little or no crevice corrosion

Example

In each case at least 99.99% pure ("4N") of copper (Cu) and alloying elements (silver (Ag) or nickel (Ni) or gold (Au) or platinum (Pt) or palladium (Pd))) of about 1200 It was dissolved in a crucible in a vacuum oven at °C. The wire core precursor item in the form of an 8 mm rod was then continuously cast from molten metal. The wire core precursor item was then drawn in several drawing steps to form a wire core precursor having a specific diameter of 18±0.5 μm. The cross section of the wire core was essentially circular.

The final strand annealing of the 18 μm wire core precursor was performed at an oven setting temperature of 630° C. for an exposure time of 0.85 seconds, and then the wire thus obtained was quenched in water containing 0.05 vol% of surfactant. Strand annealing was carried out using a mixture of 95% by volume nitrogen: 5% by volume hydrogen purging gas. Finally, the annealed wire was wound on a clean anodized (plated) aluminum spool and stored in vacuum packaging.

In an alternative procedure, the final strand annealing of the 18 μm wire core precursor was performed at an oven set temperature of 550° C. for an exposure time of 0.85 seconds. All other conditions were kept the same.

In another alternative procedure, the final strand annealing of the 18 μm wire core precursor was performed at an oven set temperature of 700° C. for an exposure time of 0.85 seconds. All other conditions were kept the same.

By this procedure, several samples 1 to 9 of alloy copper wires (according to the present invention and comparative examples) and a reference copper wire (Ref) of 4N purity were produced.

Table 1 shows the composition of different wire samples 1 to 9 according to the invention.

weight% Sample Cu Ag Ni Pd Au Pt 4N Cu(Ref)
(Annealing temperature: 630℃) ≥99.99 1 (comparative example)
(Annealing temperature: 630℃) 99.9 0.1 2 (the present invention)
(Annealing temperature: 630℃) 99.5 0.5 3 (comparative example)
(Annealing temperature: 630℃) 99.0 1.0 4 (comparative example)
(Annealing temperature: 630℃) 99.0 1.0 5 (comparative example)
(Annealing temperature: 630℃) 99.0 1.0 6 (comparative example)
(Annealing temperature: 630℃) 99.0 1.0 7 (comparative example)
(Annealing temperature: 630℃) 99.0 1.0 8 (comparative example)
(Annealing temperature: 550℃) 99.5 0.5 9 (comparative example)
(Annealing temperature: 700℃) 99.5 0.5

Chemical composition of copper alloys 1 to 9

Table 2 shows predetermined test results obtained by testing wire samples 1 to 9 adhered to an Al-0.5% by weight Cu bond pad according to the above-described test method. All tests were performed with 18 μm wire.

Sample 4N Cu
(Ref) One 2 3 4 5 6 7 8 9 Average wire particle size [㎛] (according to test method A) 4 4 2.5 2.5 3.2 3.5 3.5 3.5 0.8 3.5 Average wire particle size standard deviation [㎛] (according to test method A) 0.9 0.9 0.36 0.3 0.6 0.5 0.5 0.5 0.25 0.4 Ball shape (according to test method B) - 0 + + - - - - + 0 Decentered ball (according to test method C) 0 + + - 0 0 0 0 + 0 Corrosion resistance (according to test method D) 0 + + ++ + - - - 0 0

Test results obtained for wire samples 1-9

Claims (14)

As a silver alloy copper wire comprising a wire core, the wire core itself,
(a) silver in an amount of 0.3 to 0.7% by weight,
(b) copper in an amount ranging from 99.25 to 99.7% by weight, and
(c) as an inevitable impurity, consisting of 0 to 500 ppm by weight of additional components in total,
All amounts of the above weight percent and weight ppm are based on the total weight of the core,
The wire core,
(i) intrinsic properties within the range of 2 to less than 4 μm when the average wire grain size is measured in the longitudinal direction, and
(ii) intrinsic properties in which the ratio of the average grain size measured in the longitudinal direction to the diameter of the wire core is within the range of 0.05 to 0.25, and
(iii) Intrinsic property in which the standard deviation ratio (RSD) of the average grain size to the average grain size of the core is within the range of 0.1 to 0.3 when measured in the longitudinal direction
That is, silver alloy copper wire. The silver alloy copper wire according to claim 1, wherein the average cross section is in the range of 50 to 5024 μm ² . The silver alloy copper wire according to claim 1 or 2, having a circular cross section with an average diameter in the range of 8 to 80 μm. The silver alloy copper wire according to claim 1 or 2, wherein the amount of silver is 0.5% by weight, and the amount of copper is 99.45 to 99.5% by weight. The silver alloy copper wire according to claim 1 or 2, wherein the amount of the additional component is in the range of 0 to 100 ppm by weight. The silver alloy copper wire according to claim 1 or 2, wherein the wire core has a surface, and the surface is an outer surface or an interface region between the wire core and a coating layer overlaid on the wire core. The method of claim 6, wherein the wire core is provided with a coating layer overlapping, wherein the coating layer is a single layer composed of a noble metal element or a multilayer composed of a plurality of overlapping adjacent sub-layers, each sub-layer being made of a different noble metal element. Consisting of a silver alloy copper wire. delete As a manufacturing method of a silver alloy copper wire for manufacturing the silver alloy copper wire of claim 1,
(1) (a) silver in an amount of 0.3 to 0.7% by weight, (b) copper in an amount in the range of 99.25 to 99.7% by weight, and (c) an additional component of 0 to 500 ppm by weight in total as an inevitable impurity-the% by weight And all amounts in ppm by weight are based on the total weight of the precursor item.
(2) stretching the precursor item to form a wire precursor until a desired final diameter of the wire core is obtained; And
(3) In order to form a silver alloy copper wire, the wire precursor obtained after completion of the process step (2) is finally strand annealed at an oven set temperature in the range of 600 to 680°C for an exposure time in the range of 0.1 to 3 seconds. step
Contains at least,
The wire core,
(i) intrinsic properties within the range of 2 to less than 4 μm when the average wire grain size is measured in the longitudinal direction, and
(ii) intrinsic properties in which the ratio of the average grain size measured in the longitudinal direction to the diameter of the wire core is within the range of 0.05 to 0.25, and
(iii) Intrinsic property in which the standard deviation ratio (RSD) of the average grain size to the average grain size of the core is within the range of 0.1 to 0.3 when measured in the longitudinal direction.
It characterized in that, the method of manufacturing a silver alloy copper wire. 10. The method of claim 9, wherein step (2) does not include any intermediate annealing sub-steps. The method of claim 9 or 10, wherein the final strand annealing is performed at an oven set temperature in the range of 610 to 650°C for an exposure time in the range of 0.1 to 1.5 seconds. The method of claim 9 or 10, wherein the finally strand annealed silver alloy copper wire is quenched in water which may contain one or more additives. The method according to claim 9 or 10, wherein the final strand annealing in the process step (3) is performed in an inert or reducing atmosphere. A silver alloy copper wire obtainable by the method of claim 9 or 10.