CN219486208U - Multi-strand combined rotary stranded cutting wire - Google Patents

Abstract

The utility model discloses a multi-strand combined rotary stranded cutting wire, which comprises two or more tungsten cutting filaments, wherein the multi-strand tungsten cutting filaments are mutually spirally wound and stranded to form the cutting wire, and a plurality of annular pressing surfaces are arranged on the outer surface of the cutting wire. According to the utility model, a plurality of tungsten cutting filaments are mutually spirally wound and stranded to form the cutting filaments, and after the cutting filaments are spirally wound and stranded, the overall tensile strength is greatly improved; under the condition of the same overall diameter, the tensile strength of the cutting wire after spiral winding and twisting is larger than that of a single-strand tungsten cutting filament. From the viewpoint of raw materials, the utility model improves the tensile strength per unit cross section. The outer surface of the cutting wire is provided with the annular pressing surface, and the part with the highest bulge on the outer surface after the spiral is compressed to form the annular pressing surface, so that the concave-convex degree of the whole outer surface is reduced, scratches formed on the silicon surface during cutting are reduced, and the cut surface is smoother.

Description

Multi-strand combined rotary stranded cutting wire

Technical Field

The utility model relates to the technical field of cutting lines, in particular to a multi-strand combined rotary stranded cutting wire particularly used for cutting silicon chips.

Background

The new technology industrialization process of the third-generation semiconductor new materials represented by silicon carbide and gallium nitride is accelerated in China, various products from daily use to industrial manufacture and military industry are updated and expanded day by day, the silicon carbide is applied everywhere, the application is very wide, and the demand of intelligent chips is astronomical figures. High-end silicon carbide raw material bars for producing chips can be used by cutting into thin slices, while silicon carbide is a very hard and compact semiconductor material, and has very high cost and very low cutting speed and efficiency. The production mode adopted by the current market practice is that the carbon steel wire drives mortar to grind and cut, and the cutting mode of taking the carbon steel wire as a cutting consumable material brings defects of low one-time yield, low speed, stripes on the surface of the finished product and the like, so that the requirement of precise cutting of silicon carbide can not be completely met.

The inventor invents a high-performance rare earth alloy tungsten cutting line, wherein a tree-shaped concave resistance is formed on the surface of the tungsten cutting line, so that the binding force between a metal coating and a tungsten wire can be improved, the consolidation quality of diamond particles is ensured, and the service life of the cutting line is prolonged on the basis of ensuring enough tensile strength. For specific structure, reference is made to the chinese patent application publication No. CN114480936a filed by the inventor at 2022, 2 and 24. After the product is released from the market, the product is widely appreciated by users. However, during use, there is still room for improvement:

as silicon wafers are more expensive, a higher requirement is placed on the material loss ratio in the cutting process, and it is known from experiments that the thinner the cutting line is, the lower the material loss is, so that the diameter of the cutting line needs to be made smaller. The diameter of the cutting line becomes smaller, which causes problems that the tensile strength is reduced and the service life is shortened, so that the cutting line needs to be improved, and the diameter of the cutting line is reduced while a certain tensile strength is ensured.

Disclosure of Invention

In order to overcome the defects of the prior art, the multi-strand combined rotary stranded cutting wire with small diameter, high tensile strength and long service life is provided.

The technical scheme adopted for solving the technical problems is as follows:

the multi-strand combined rotary stranded cutting wire comprises two or more tungsten cutting filaments, wherein the multi-strand tungsten cutting filaments are mutually spirally wound and stranded to form the cutting wire, and a plurality of annular pressing surfaces are arranged on the outer surface of the cutting wire.

In the utility model, the outer surface of the cutting wire is provided with a chip removal groove in a spiral shape for cutting chip removal.

In the utility model, the outer surface of the cutting wire is provided with diamond powder particles.

In the present utility model, the diameter of the individual strands of tungsten cutting filaments is between 0.015mm and 0.15 mm.

In the present utility model, the helical twist angle of the single strand tungsten cutting filament per cm is between 3600 ° and 7200 °.

In the present utility model, the cross section of the cutting wire is circular.

In the utility model, the cross section of the cutting wire is a regular polygon.

The beneficial effects of the utility model are as follows: according to the utility model, a plurality of tungsten cutting filaments are mutually spirally wound and stranded to form the cutting filaments, and after the cutting filaments are spirally wound and stranded, the overall tensile strength is greatly improved; under the condition of the same overall diameter, the tensile strength of the cutting wire after spiral winding and twisting is larger than that of a single-strand tungsten cutting filament. From the viewpoint of raw materials, the utility model improves the tensile strength per unit cross section.

Furthermore, the outer surface of the cutting wire is provided with the annular pressing surface, and the part with the highest bulge on the outer surface after the spiral is compressed to form the annular pressing surface, so that the concave-convex degree of the whole outer surface is reduced, scratches formed on the silicon surface during cutting are reduced, and the cut surface is smoother.

Furthermore, after the multi-strand tungsten cutting filaments are spirally wound and twisted, chip removal grooves are reserved between the adjacent tungsten cutting filaments, so that the chip removal grooves are convenient for the flow of chips during cutting, the scratches on the silicon surface are reduced, the heat removal effect can be achieved, and the temperature generated during cutting is reduced. Under the mortar cutting environment, larger mortar flow can be driven, so that the cutting speed is improved.

Drawings

The utility model is further described below with reference to the drawings and embodiments:

FIG. 1 is a schematic diagram of a first embodiment;

FIG. 2 is a top view of the first embodiment;

FIG. 3 is a schematic diagram of a structure during processing according to an embodiment;

FIG. 4 is a schematic structural view of the working mold in FIG. 3;

FIG. 5 is a schematic diagram of a second embodiment;

fig. 6 is a front view of the second embodiment;

fig. 7 is a plan view of the second embodiment.

Detailed Description

The following description of the embodiments of the present utility model will be made clearly and completely with reference to the accompanying drawings, in which it is apparent that the embodiments described are only some embodiments of the present utility model, but not all embodiments. All other embodiments, which can be made by those skilled in the art based on the embodiments of the utility model without making any inventive effort, are intended to be within the scope of the utility model.

In the description of the present utility model, it should be noted that the directions or positional relationships indicated by the terms "upper", "lower", "inner", "outer", "left", "right", "top/bottom", etc. are based on the directions or positional relationships shown in the drawings, are merely for convenience of describing the present utility model and simplifying the description, and do not indicate or imply that the apparatus or elements referred to must have a specific orientation, be constructed and operated in a specific orientation, and thus should not be construed as limiting the present utility model. Furthermore, the terms "first," "second," and the like, are used for descriptive purposes only and are not to be construed as indicating or implying relative importance.

In the description of the present utility model, it should be noted that, unless explicitly specified and limited otherwise, the terms "mounted," "configured to," "engaged with," "connected to," and the like are to be construed broadly, and may be either fixedly connected, detachably connected, or integrally connected, for example; can be mechanically or electrically connected; can be directly connected or indirectly connected through an intermediate medium, and can be communication between two elements. The specific meaning of the above terms in the present utility model will be understood in specific cases by those of ordinary skill in the art.

Embodiment one:

referring to fig. 1 to 4, the multi-strand combined rotary stranded cutting wire provided in this embodiment includes two or more tungsten cutting filaments 1, the multi-strand tungsten cutting filaments 1 are spirally wound and stranded with each other to form the cutting wire, and a plurality of annular pressing surfaces 2 are provided on the outer surface of the cutting wire. In this embodiment, the tungsten cutting filaments 1 are provided in three strands, and the diameter of the whole cutting filament is twice that of a single strand of tungsten cutting filaments 1. The diameter of the single-strand tungsten cutting filament 1 is between 0.015mm and 0.15mm, preferably 0.04mm, and the diameter of the whole cutting filament is only 0.075mm after subsequent processing, and the whole tensile strength and the service life are better than those of the single-strand tungsten cutting filament with the diameter of 0.075mm, and only half of the existing steel wire of 0.15mm, so that the cutting seam is smaller, the yield is higher than 15%, and the raw material loss rate is greatly reduced. According to the prior art, the unit price of the silicon carbide piece with the thickness of 0.68mm is 6000 yuan/piece, the loss of one seam is 0.15mm, and the loss of one seam is 0.075mm, so that one silicon carbide raw material can be cut into more than a few pieces or even more than ten and a few tens of pieces on the basis of the prior art, and the silicon carbide piece with the value of hundreds of thousands yuan can be produced.

In the embodiment, the tungsten cutting filament 1 is a high-performance rare earth alloy tungsten cutting line, the tungsten cutting filament 1 is made of materials synthesized according to the weight percentage of 99.75-99.15% of tungsten and 0.25-0.85% of rare earth, and the rare earth contains more than 99.99% of lanthanum according to the weight percentage; specific molding processes and structures are described in the chinese patent application publication No. CN114480936a, filed by the present inventors at 24, 2, 2022, and not described in detail herein.

In this embodiment, the annular pressing surface 2 is formed by pressing an annular pressing mold 4 made of tungsten steel or CVD diamond, and as shown in fig. 3 and 4, a pressing hole 40 is provided in the middle of the annular pressing mold 4. The front section of the press-cutting hole is an inlet area 41 with a greatly reduced diameter, and the opening angle of the inlet area 41 is 60-90 degrees. The guiding zone 41 is followed by a lubrication zone 42 and a compression zone 43 of decreasing diameter in sequence, the opening angles of the lubrication zone 42 and the compression zone 43 being 30 ° to 40 ° and 12 ° to 24 °, respectively. The rear section of the compression zone 43 is a sizing zone 44 with equal diameter, and the sizing zone 44 is smaller than the diameter of the cutting wire after the three-strand tungsten cutting filaments 1 are spirally wound and stranded. The guiding zone 41 is followed by a relief angle 45 and an outlet zone 46 of gradually increasing diameter, the opening angles of the relief angle 45 and the outlet zone 46 being 10 ° and 60 ° to 90 °, respectively. In the press cutting, the annular press cutting die 4 is required to be placed in a high-temperature furnace for heating, the temperature in the furnace is 350 ℃, and the die temperature is approximately 400 ℃. The ratio of the diameter after pressing and cutting to the diameter before pressing and cutting is 84% -92%: 1, preferably 92%:1, the preferable speed of the press cutting is 50-150 mm/min. The highest protruding part of the outer surface is flattened or cut off through the annular pressing and cutting die 4, so that the annular pressing surface 2 is formed, the flatness of the outer surface of the whole cutting wire is guaranteed, scratches formed on the silicon surface during cutting are reduced, and the cut surface is smoother. The finished product after cutting has high surface smoothness, is not easy to generate cutting stripes, reduces the polishing and reprocessing difficulty, has high primary yield and excellent quality, and can meet the requirements of high-stability, high-precision, high-quality and ultra-thin processing.

Meanwhile, after ring pressing, the three strands of tungsten cutting filaments 1 are spirally wound and twisted to be more compact, and the structure is firmer. Meanwhile, the high-temperature die can eliminate internal stress when the tungsten cutting filament 1 is spirally twisted, so that the internal structure is more stable and is not easy to deform. In this embodiment, the cross section of the cutting hole is circular, and the cross section of the whole cutting wire after cutting is also circular. Of course, the cross section of the cutting hole can also be a regular polygon, so that the cross section of the whole cutting wire after being pressed and cut is also a regular polygon to cope with different cutting environments.

As the preferred implementation mode, after the three tungsten cutting filaments 1 are spirally wound and twisted, the spiral chip removal grooves 3 are reserved between the adjacent tungsten cutting filaments 1, and the chip removal grooves 3 not only facilitate the flow of chips during cutting and reduce the scratches on the silicon surface, but also play a role in heat removal, reduce the temperature generated during cutting and ensure better cutting effect. The surface of the conventional cutting wire is a smooth surface, so that cutting in mortar is required, or diamond powder is added to the surface of the cutting wire. The cutting is performed by means of the flow of mortar, and the greater the flow rate of mortar is, the faster the cutting speed is. The chip removal groove 3 can drive larger mortar flow under the mortar environment, and the mortar flow can be three times of that of the traditional cutting wire. A conventional silicon carbide bar with the length of 150mm (6 inches) is cut, a common carbon steel wire can be cut in 7-8 days, and the spiral chip removal groove 3 is adopted to remove chips in a half way, so that the yield and the speed are higher than those of a traditional method by more than 100%, the broken wire is less, the equipment failure rate is low, the maintenance frequency is reduced, and the equipment efficiency and the utilization rate are higher.

When working in a non-mortar environment, diamond powder particles with tiny volumes can be arranged on the outer surface of the cutting wire, so that friction on the surface of the cutting wire is increased, and the cutting effect is ensured.

In this embodiment, the single strand of tungsten cutting filaments 1 per centimeter is helically twisted at an angle of between 3600 ° and 7200 °, i.e., three strands of tungsten cutting filaments 1 one centimeter long are helically twisted with each other, the number of turns of the helix is between 10 and 20 turns, and so on. The preferred helical twist angle of the single strand tungsten cutting filaments 1 per centimeter is 4800 ° when the diameter of the single strand tungsten cutting filaments 1 is 0.02 mm. Here, the smaller the diameter, the larger the helical twist angle, and when the diameter is larger and the helical twist angle is smaller, a good twisting effect cannot be achieved; when the twist angle is too large, not only the winding diameter is too large, but also the tensile strength is not improved much.

Embodiment two:

referring to fig. 5 to 7, the structure and principle of the present embodiment are substantially the same as those of the first embodiment, except that the tungsten cutting filaments 1 are provided in two strands, and the overall cutting filaments have twice the diameter of the single-strand tungsten cutting filaments 1 after being cut through the cutting holes. In this embodiment, the diameter of the single strand of tungsten cutting filament 1 is preferably 0.05mm, so that the diameter of the whole cutting filament is only 0.09mm, and the whole tensile strength and service life are better than those of the single strand of tungsten cutting filament with the diameter of 0.09mm, and the cutting seam is thinner, thereby saving more materials.

In addition, the utility model is not limited to tungsten wires, but can be wires made of other metal materials and having certain tensile strength, and the structure of the utility model can be adopted to form stranded cutting wires.

The foregoing is only a preferred embodiment of the present utility model, and all technical solutions for achieving the object of the present utility model by substantially the same means are within the scope of the present utility model.

Claims (7)

1. The rotatory transposition cutting wire of stranded merger, its characterized in that: the cutting wire comprises two or more tungsten cutting filaments (1), wherein a plurality of tungsten cutting filaments (1) are mutually spirally wound and stranded to form the cutting wire, and a plurality of annular pressing surfaces (2) are arranged on the outer surface of the cutting wire.

2. The multi-strand, combined rotary stranded cutting wire of claim 1, wherein: the outer surface of the cutting wire is provided with a chip removal groove (3) which is used for cutting and removing chips and has a spiral shape.

3. The multi-strand, combined rotary stranded cutting wire of claim 1 or 2, wherein: and diamond powder particles are arranged on the outer surface of the cutting wire.

4. The multi-strand, combined rotary stranded cutting wire of claim 1 or 2, wherein: the diameter of the single strand tungsten cutting filaments (1) is between 0.015mm and 0.15 mm.

5. The multi-strand, combined rotary stranded cutting wire of claim 1 or 2, wherein: the helical twist angle of the single strand tungsten cutting filaments (1) per centimeter is between 3600 DEG and 7200 deg.

6. The multi-strand, combined rotary stranded cutting wire of claim 1 or 2, wherein: the cross section of the cutting wire is circular.

7. The multi-strand, combined rotary stranded cutting wire of claim 1 or 2, wherein: the cross section of the cutting wire is regular polygon.