JP2015174178A - Cutting-tool cutting method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a cutting-tool cutting method excellent in efficiency capable of properly processing a workpiece including metal.SOLUTION: A cutting-tool cutting method cuts a workpiece (11) including metal in at least a cutting object surface (11a) by cutting-tool cutting means (32), and comprises a cutting-tool cutting step of cutting the workpiece by the cutting-tool cutting means while supplying a cutting liquid (50) on the cutting object surface of the workpiece, and is constituted so that the cutting liquid includes an organic acid and an oxidizer.

Description

  The present invention relates to a cutting tool method for cutting a workpiece including metal.

  A flip chip is known as one technique for mounting a chip on a substrate or the like. In the flip chip, the chip and the substrate are connected by conductive protrusions (bumps) provided on the surface side of the chip. Therefore, the area required for mounting the chip is smaller than that of wire bonding using a conductive wire. Can be small.

  By the way, if there is variation in the height of the bumps described above, a problem is likely to occur in the connection between the chip and the substrate. Therefore, after the bumps are arranged on the front surface side of the wafer, processing for aligning the bump height is usually performed before dividing the wafer into chips.

  Since a material such as a ductile metal is plastically stretched when stress is applied, it is not easy to appropriately process a bump including the metal by a method such as grinding with a large stress. Therefore, for the processing of the bumps, a method such as cutting with a bit which is difficult to apply stress is used (for example, see Patent Document 1).

JP 2009-4406 A

  However, even when this cutting tool is used, if the processing speed is increased, the applied stress increases and the bumps are extended. Therefore, this method has a problem in processing efficiency.

  This invention is made | formed in view of this problem, The place made into the objective is providing the efficient cutting tool method which can process the workpiece containing a metal appropriately.

  According to the present invention, there is provided a cutting tool for cutting a workpiece containing at least a metal on a cutting surface with a cutting tool, and the workpiece is supplied while supplying a cutting fluid onto the cutting surface of the workpiece. There is provided a tool cutting method comprising a tool cutting step for cutting with the tool cutting means, wherein the cutting fluid contains an organic acid and an oxidizing agent.

  In the present invention, the cutting fluid preferably further contains an anticorrosive agent.

  In the cutting tool method according to the present invention, by supplying a working fluid containing an organic acid and an oxidizing agent, the metal contained in the surface to be cut can be modified to suppress ductility. The workpiece can be cut properly. That is, according to the present invention, an efficient cutting method for cutting a workpiece including metal can be provided.

It is a perspective view showing typically an example of composition of a cutting tool used with a cutting method concerning this embodiment. It is a partial cross section side view showing typically a cutting tool step.

  Embodiments of the present invention will be described with reference to the accompanying drawings. First, a configuration example of a cutting tool used in the cutting method according to the present embodiment will be described. FIG. 1 is a perspective view schematically showing a configuration example of a cutting tool according to the present embodiment. As shown in FIG. 1, the cutting tool 2 according to this embodiment includes a rectangular parallelepiped base 4 on which various configurations are mounted. At the rear end of the base 4, a support wall 6 extending upward is erected.

  An opening 4 a is formed on the front side of the upper surface of the base 4, and a transport mechanism 8 for transporting the plate-like workpiece 11 is provided in the opening 4 a. Further, cassettes 10a and 10b for accommodating the workpiece 11 are placed in a region on the side of the opening 4a.

  The workpiece 11 is, for example, a disk-shaped semiconductor wafer, and bumps 13 made of metal or the like are provided on the surface 11a (see FIG. 2) side which is a surface to be cut. However, the configuration of the workpiece 11 is not limited to this. If it is a plate-like object containing metal on the surface to be cut, such as a metal plate, a TSV wafer provided with TSV (Through Silicon Via), or a wafer formed with a metal film, it is processed by the cutting method according to the present embodiment. it can.

  An alignment mechanism 12 that aligns the temporarily placed workpiece 11 is provided behind the placement area where the cassette 10a is placed. For example, the workpiece 11 conveyed by the conveyance mechanism 8 from the cassette 10a is placed on the alignment mechanism 12 and the center thereof is aligned.

  A carry-in mechanism 14 that holds and rotates the workpiece 11 is provided behind the alignment mechanism 12. An opening 4 b is formed behind the carry-in mechanism 14. In this opening 4b, an X-axis moving table 16, an X-axis moving mechanism (not shown) for moving the X-axis moving table 16 in the X-axis direction (front-rear direction), and a waterproof cover 18 covering the X-axis moving mechanism are arranged. Has been.

  The X-axis movement mechanism includes a pair of X-axis guide rails (not shown) parallel to the X-axis direction, and an X-axis movement table 16 is slidably installed on the X-axis guide rails. A nut portion (not shown) is fixed to the lower surface side of the X-axis moving table 16, and an X-axis ball screw (not shown) parallel to the X-axis guide rail is screwed to the nut portion.

  An X-axis pulse motor (not shown) is connected to one end of the X-axis ball screw. By rotating the X-axis ball screw with the X-axis pulse motor, the X-axis moving table 16 moves in the X-axis direction along the X-axis guide rail. On the X-axis moving table 16, a chuck table 20 for sucking and holding the workpiece 11 is provided.

  The chuck table 20 is connected to a rotation drive source (not shown) such as a motor, and rotates around a rotation axis extending in the Z-axis direction (vertical direction). Further, the chuck table 20 is moved between a front loading / unloading position where the workpiece 11 is loaded / unloaded and a rear cutting position where the workpiece 11 is bite-cut by the above-described X-axis moving mechanism. .

  A part of the upper surface of the chuck table 20 serves as a holding surface 20a (see FIG. 2) that holds the workpiece 11 by suction. The holding surface 20 a is connected to the suction source 20 c through a flow path 20 b formed inside the chuck table 20. The workpiece 11 carried in by the carry-in mechanism 14 is sucked and held on the chuck table 20 by the negative pressure of the suction source 20c acting on the holding surface 20a.

  A Z-axis moving mechanism 22 is provided on the front surface of the support wall 6. The Z-axis moving mechanism 22 includes a pair of Z-axis guide rails 24 parallel to the Z-axis direction, and a Z-axis moving table 26 is slidably installed on the Z-axis guide rails 24. A nut portion (not shown) is fixed to the rear surface side (back surface side) of the Z-axis moving table 26, and a Z-axis ball screw 28 parallel to the Z-axis guide rail 24 is screwed to the nut portion. Yes.

  A Z-axis pulse motor 30 is connected to one end of the Z-axis ball screw 28. By rotating the Z-axis ball screw 28 by the Z-axis pulse motor 30, the Z-axis moving table 26 moves in the Z-axis direction along the Z-axis guide rail 24.

  At a position close to the Z-axis guide rail 24, a Z-axis scale (not shown) indicating the position (height position) of the Z-axis moving table 26 in the Z-axis direction is attached. The position of the Z-axis movement table 26 in the Z-axis direction is read by a scale reading mechanism (not shown) provided in the Z-axis movement table 26.

  On the front surface (surface) of the Z-axis moving table 26, a cutting mechanism (cutting means) 32 for cutting the workpiece 11 is provided. The cutting mechanism 32 includes a spindle housing 34 fixed to the Z-axis moving table 26. The spindle housing 34 supports a spindle 36 that can rotate around a rotation axis extending in the Z-axis direction.

  A disk-shaped bite wheel 38 is connected to the lower end portion of the spindle 36, and a bite 40 having a cutting blade made of single crystal diamond or the like is attached to the bite wheel 38. A rotary drive source (not shown) such as a motor is connected to the upper end side of the spindle 36, and the bite wheel 38 (bite 40) rotates with the rotational force transmitted from the rotary drive source.

  Further, the cutting tool 40 is moved closer to and away from the workpiece 11 sucked and held by the chuck table 20 by the Z-axis moving mechanism 22 described above. Thereby, the cutting edge of the cutting tool 40 can be positioned at an arbitrary height, and the surface 11a side of the workpiece 11 can be cut.

  At a position adjacent to the cutting mechanism 32, a nozzle 42 for supplying a machining fluid 50 (see FIG. 2) to the surface 11a side of the workpiece 11 is provided. The nozzle 42 is connected to a machining liquid supply source (not shown). By supplying the machining fluid 50 and positioning the rotating bite wheel 38 at a predetermined height and bringing the bite 40 into contact, the bumps 13 disposed on the surface 11a side of the workpiece 11 can be appropriately cut. Details of the machining fluid 50 will be described later.

  An unloading mechanism 44 that holds and rotates the workpiece 11 is provided at a position adjacent to the loading mechanism 14 in the Y-axis direction (left-right direction). A cleaning mechanism 46 for cleaning the workpiece 11 after cutting the cutting tool is disposed in front of the unloading mechanism 44 and behind the mounting area where the cassette 10b is mounted.

  The workpiece 11 cleaned by the cleaning mechanism 46 is transported by the transport mechanism 8 and stored in the cassette 10b. In front of the opening 4a, an operation panel 48 for inputting cutting tool conditions such as the number of rotations of the spindle 36, the lowering speed of the cutting tool 38, and the supply amount of the machining fluid 50 is provided.

  Next, a cutting tool method using the above-described cutting device 2 will be described. First, a holding step for holding the workpiece 11 on the chuck table 20 is performed. In this holding step, the back surface 11b (see FIG. 2) side of the workpiece 11 is brought into contact with the holding surface 20a of the chuck table 20, and the negative pressure of the suction source 20c is applied. As a result, the workpiece 11 is sucked and held on the chuck table 20.

  After the holding step, a cutting tool step for cutting the workpiece 11 is performed. FIG. 2 is a partial cross-sectional side view schematically showing a cutting tool step. In the cutting tool step, the cutting wheel of the cutting tool 40 is positioned at a predetermined height by lowering the cutting tool wheel 38 while rotating the spindle 36. Further, the chuck table 20 is moved in the X-axis direction, and the bumps 13 of the workpiece 11 are brought into contact with the cutting blade of the rotating cutting tool 40.

  In addition, the machining liquid 50 is supplied from the nozzle 42 to the surface 11 a of the workpiece 11. In the processing method according to the present embodiment, a processing liquid 50 containing an organic acid and an oxidizing agent is used. With this machining liquid 50, the bump 13 made of metal disposed on the surface 11a side of the workpiece 11 can be modified (brittle) and cut while suppressing ductility.

  Therefore, even if the rotational speed of the bite wheel 38 is increased to increase the processing speed, no burrs (projections) are generated from the bumps 13. That is, the workpiece 11 can be appropriately cut by cutting even when the processing speed is increased. Further, since no burrs are generated from the bumps 13, the bumps 13 and the like arranged at a narrow pitch can be processed without reducing the reliability.

  As the organic acid, for example, a compound having at least one carboxyl group and at least one amino group in the molecule can be used. In this case, at least one of the amino groups is preferably a secondary or tertiary amino group. In addition, the compound used as the organic acid may have a substituent.

  Examples of amino acids that can be used as organic acids include glycine, dihydroxyethyl glycine, glycyl glycine, hydroxyethyl glycine, N-methyl glycine, β-alanine, L-alanine, L-2-aminobutyric acid, L-norvaline, L -Valine, L-leucine, L-norleucine, L-alloisoleucine, L-isoleucine, L-phenylalanine, L-proline, sarcosine, L-ornithine, L-lysine, taurine, L-serine, L-threonine, L- Allothreonine, L-homoserine, L-thyroxine, L-tyrosine, 3,5-diiodo-L-tyrosine, β- (3,4-dihydroxyphenyl) -L-alanine, 4-hydroxy-L-proline, L- Cysteine, L-methionine, L-ethionine, L-lanthionine, L-cysta Thionine, L-cystine, L-cysteic acid, L-glutamic acid, L-aspartic acid, S- (carboxymethyl) -L-cysteine, 4-aminobutyric acid, L-asparagine, L-glutamine, azaserine, L-canavanine, L-citrulline, L-arginine, δ-hydroxy-L-lysine, creatine, L-kynurenine, L-histidine, 1-methyl-L-histidine, 3-methyl-L-histidine, L-tryptophan, actinomycin C1, Examples include ergothioneine, apamin, angiotensin I, angiotensin II, and antipine. Of these, glycine, L-alanine, L-proline, L-histidine, L-lysine, and dihydroxyethylglycine are preferable.

  Examples of aminopolyacids that can be used as organic acids include iminodiacetic acid, nitrilotriacetic acid, diethylenetriaminepentaacetic acid, ethylenediaminetetraacetic acid, hydroxyethyliminodiacetic acid, nitrilotrismethylenephosphonic acid, ethylenediamine-N, N, N ′, N'-tetramethylenesulfonic acid, 1,2-diaminopropanetetraacetic acid, glycol etherdiaminetetraacetic acid, transcyclohexanediaminetetraacetic acid, ethylenediamine orthohydroxyphenylacetic acid, ethylenediamine disuccinic acid (SS form), β-alanine diacetic acid, N -(2-carboxylate ethyl) -L-aspartic acid, N, N′-bis (2-hydroxybenzyl) ethylenediamine-N, N′-diacetic acid and the like.

  Further, carboxylic acids that can be used as organic acids include formic acid, glycolic acid, propionic acid, acetic acid, butyric acid, valeric acid, hexanoic acid, oxalic acid, malonic acid, glutaric acid, adipic acid, malic acid, succinic acid , Pimelic acid, mercaptoacetic acid, glyoxylic acid, chloroacetic acid, pyruvic acid, acetoacetic acid, glutaric acid and other saturated carboxylic acids, acrylic acid, methacrylic acid, crotonic acid, fumaric acid, maleic acid, mesaconic acid, citraconic acid, aconite Examples include unsaturated carboxylic acids such as acids, cyclic unsaturated carboxylic acids such as benzoic acids, toluic acid, phthalic acids, naphthoic acids, pyrometic acid, and naphthalic acid.

  Examples of the oxidizing agent include hydrogen peroxide, peroxide, nitrate, iodate, periodate, hypochlorite, chlorite, chlorate, perchlorate, persulfate, Bichromate, permanganate, cerate, vanadate, ozone water, silver (II) salt, iron (III) salt, and organic complex salts thereof can be used.

  Further, the processing liquid 50 may be mixed with an anticorrosive agent. By mixing the anticorrosive agent, corrosion (elution) of the metal contained in the workpiece 11 can be prevented. As the anticorrosive, for example, a heteroaromatic ring compound having 3 or more nitrogen atoms in the molecule and having a condensed ring structure, or a heteroaromatic ring compound having 4 or more nitrogen atoms in the molecule It is preferable to use it. Furthermore, the aromatic ring compound preferably contains a carboxyl group, a sulfo group, a hydroxy group, or an alkoxy group. Specifically, tetrazole derivatives, 1,2,3-triazole derivatives, and 1,2,4-triazole derivatives are preferable.

  The tetrazole derivative that can be used as an anticorrosive agent has no substituent on the nitrogen atom forming the tetrazole ring, and a sulfo group, amino group, carbamoyl group, carbonamido group, sulfamoyl group at the 5-position of the tetrazole ring. A substituent selected from the group consisting of a group and a sulfonamide group, or a group selected from the group consisting of a hydroxy group, a carboxy group, a sulfo group, an amino group, a carbamoyl group, a carbonamido group, a sulfamoyl group, and a sulfonamide group In addition, an alkyl group substituted with at least one substituent is introduced.

  Moreover, as a 1,2,3-triazole derivative which can be used as an anticorrosive, it does not have a substituent on the nitrogen atom which forms a 1,2,3-triazole ring, and 1,2,3- A substituent selected from the group consisting of a hydroxy group, a carboxy group, a sulfo group, an amino group, a carbamoyl group, a carbonamido group, a sulfamoyl group, and a sulfonamide group at the 4-position and / or 5-position of the triazole; An alkyl group or an aryl group substituted with at least one substituent selected from the group consisting of a group, a carboxy group, a sulfo group, an amino group, a carbamoyl group, a carbonamido group, a sulfamoyl group, and a sulfonamido group was introduced Things.

  Moreover, as a 1,2,4-triazole derivative which can be used as an anticorrosive, it does not have a substituent on the nitrogen atom which forms a 1,2,4-triazole ring, and 1,2,4- A substituent selected from the group consisting of a sulfo group, a carbamoyl group, a carbonamido group, a sulfamoyl group, and a sulfonamido group at the 2-position and / or 5-position of the triazole, or a hydroxy group, a carboxy group, a sulfo group, an amino group And an alkyl group or aryl group substituted with at least one substituent selected from the group consisting of a group, a carbamoyl group, a carbonamido group, a sulfamoyl group, and a sulfonamido group.

  As described above, in the cutting tool method according to the present embodiment, the metal contained in the surface (surface to be cut) 11a is modified (brittle) by supplying the machining liquid 50 containing an organic acid and an oxidizing agent. ) And the ductility can be suppressed, so that the workpiece 11 can be appropriately cut by cutting even when the processing speed is increased. That is, according to the present embodiment, an efficient cutting tool that can appropriately process the workpiece 11 containing metal is provided.

  Further, in the cutting tool method according to the present embodiment, by supplying a working fluid 50 containing an organic acid and an oxidizing agent, an iron-based material such as nickel or iron formed by a method such as electrolytic nickel plating, titanium, etc. It is possible to reduce the reactivity with the cutting tool 40 by reducing the toughness of a difficult-to-cut material such as This makes it possible to appropriately process these materials that could not be processed by the conventional cutting tool method.

  In addition, this invention is not limited to description of the said embodiment, A various change can be implemented. For example, the machining liquid 50 is not necessarily limited to the above-described configuration. As the organic acid, other amino acids, aminopolyacids, carboxylic acids and the like may be used. Further, other azole compounds (tetrazole, triazole, benzotriazole, etc.) may be used as anticorrosive agents.

  In addition, the configurations, methods, and the like according to the above-described embodiments can be changed as appropriate without departing from the scope of the object of the present invention.

2 Bite grinding device 4 Base 4a, 4b Opening 6 Support wall 8 Transport mechanism 10a, 10b Cassette 12 Positioning mechanism 14 Loading mechanism 16 X-axis moving table 18 Waterproof cover 20 Chuck table 20a Holding surface 20b Flow path 20c Suction source 22Z Axis moving mechanism 24 Z-axis guide rail 26 Z-axis moving table 28 Z-axis ball screw 30 Z-axis pulse motor 32 Cutting mechanism (bite cutting means)
34 Spindle housing 36 Spindle 38 Bite wheel 40 Bite 42 Nozzle 44 Unloading mechanism 46 Cleaning mechanism 48 Operation panel 50 Working fluid 11 Workpiece 11a Surface (surface to be cut)
11b Back side 13 Bump

Claims (2)

A cutting tool for cutting a workpiece containing metal at least on a cutting surface with a cutting tool,
A cutting tool step of cutting the workpiece with the cutting tool while supplying a cutting fluid onto the cutting surface of the workpiece;
The cutting tool characterized in that the cutting fluid contains an organic acid and an oxidizing agent. The cutting tool according to claim 1, wherein the cutting fluid further contains an anticorrosive agent.

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