KR20190026590A - Machining method - Google Patents

Abstract

An objective of the present invention is to allow the possibility of performing smooth processing while suppressing the abrasion of a processing stone when processing a workpiece formed by grinding and the like. The processing method comprises: a holding step of holding a workpiece (W) with a holding table (30) having a holding surface (300a) to hold the workpiece (W); and a processing step of processing the workpiece (W) with a processing means (7) including a processing stone (74a) in which abrasive grains are bonded through vitrification after performing the holding step. In the processing step, processing water is supplied to the workpiece (W), and light having a predetermined wavelength is irradiated from a light irradiation means (9) to the processing surface of the processing stone (74a).

Description

MACHINING METHOD

The present invention relates to a machining method for machining a workpiece with a machined grinding wheel in which abrasive grains are combined with non-tritide.

BACKGROUND ART Plate-shaped workpieces such as semiconductor wafers are ground by grinding to a predetermined thickness and then divided by cutting into individual device chips, which are used in various electronic devices and the like. In the case where the wafer is formed by removing an arc such as gallium nitride (GaN), silicon carbide (SiC), or gallium arsenide (GaAs), a grinding method using a grinding stone in which abrasives are combined with non- And a cutting method using a cutting stone (for example, refer to Patent Document 2) in which abrasive grains are combined with non-trivial is widely used.

Patent Document 1: Japanese Patent Laid-Open Publication No. 2014 -124690 Patent Document 2: Japanese Patent Application Laid-Open No. 2013-219215

However, in any of the above methods, there is a problem that the amount of abrasion of the grinding stone is more than necessary and the production cost is increased. In addition, there is a problem in that the machining ability of the grinding wheel is lowered at the time of machining the workpiece formed by the grinding, resulting in lowering the productivity. Further, there is also a problem that machining becomes difficult due to the ductility of the metal even when the workpiece containing the metal is machined at the machining position by the grinding wheel.

Therefore, in the case of machining a workpiece formed by grinding or the like, there is a problem that excessive wear of the machined stone is suppressed and smooth and stable machining can be performed.

According to the present invention, there is provided a method of machining a workpiece, comprising: a holding step of holding a workpiece with a holding table having a holding surface for holding the workpiece; And a machining step of machining the workpiece with a machining means including a machined grinding wheel coupled to the workpiece grinding wheel, wherein in the machining step, the machining water is supplied to the workpiece, And the surface is irradiated.

The present invention for solving the above problems is characterized in that the machining means has a cutting blade having the machining wheel, and the machining step is a machining method of cutting the workpiece with the cutting blade.

The present invention for solving the above problems is characterized in that the machining means includes a grinding wheel having the grinding wheel, and in the grinding step, the grinding wheel grinds the workpiece.

A method for machining a workpiece according to the present invention includes: a holding step of holding a workpiece with a holding table having a holding surface for holding a workpiece; and a grinding stone having a grinding wheel And a processing step of processing the workpiece by the machining means. In the machining step, the machining water is supplied to the workpiece, and light having a predetermined wavelength is irradiated from the light irradiation means to the machined surface of the machined stone. Thereby making it possible to improve the cooling effect by the processed water to suppress the excessive wear of the processed grinding stone and improve the dischargeability of the processed debris. In addition, since the process water is effectively supplied to the machining area of the machined stone by the hydrophilization of the machined stone, deterioration of the machining quality due to the machining heat can be prevented, Can be performed.

1 is a perspective view showing an example of a grinding apparatus.
2 is a perspective view showing an example of the positional relationship between the grinding means, the holding table, and the light irradiation means.
3 is a cross-sectional view showing a state in which a workpiece held on a holding table is ground with a grinding stone.
Fig. 4 (a) is an explanatory diagram of a case where the rotational locus of the grinding wheel during grinding and the positional relationship between the working region of the workpiece and the light irradiating means by the grinding wheel are viewed from above. Fig. Fig. 4 (b) is an explanatory view of a state in which the processed grinding stone immediately after the light is irradiated on the machining surface is seen in the side view. Fig.
5 is a cross-sectional view partially showing a state in which washing water is supplied to the cover on the light emitting portion during grinding.
6 is a plot showing the effect of ultraviolet light irradiation at a wavelength of 365 nm on the machined surface of the working grinding stone at the time of grinding obtained by conducting the experiment 1. Fig.
7 is a perspective view showing an example of a cutting apparatus.
8 is a cross-sectional view showing a holding table and a cutting means holding a workpiece.
9 is a cross-sectional view showing a state in which a workpiece held on a holding table is cut by cutting means.

(Embodiment 1)

The grinding apparatus 1 shown in Fig. 1 is an apparatus for grinding a workpiece W held on a holding table 30 by a machining means 7 having a grinding wheel 74. Fig. The front side (-Y direction side) of the base 10 of the grinding apparatus 1 is the attaching / detaching area A which is an area where the workpiece W is attached to / detached from the holding table 30, The back side of the workpiece 10 is the machining area B which is the area where the workpiece W is ground by the machining means 7. [ On the front side of the base 10, input means 12 for inputting machining conditions and the like to the grinding machine 1 is arranged by the operator.

The holding table 30 has a circular shape and has a suction portion 300 for suctioning the workpiece W and a frame 301 for supporting the suction portion 300. The adsorption unit 300 communicates with a suction source (not shown) to suck and hold the workpiece W on the holding surface 300a, which is the exposed surface of the adsorption unit 300. [ The holding surface 300a of the holding table 30 is formed as a conical surface having a very gentle slope with the rotation center of the holding table 30 as a vertex. The holding table 30 is surrounded by the cover 31 and is rotatable around the axis in the Z axis direction and is disposed below the pleat box cover 31a connected to the cover 31 and the cover 31 Axis direction by means of a Y-axis direction transfer means (not shown) which is connected to the attachment / detachment area A and the processing area B.

In the machining area B, a column 11 is provided upright. On the side surface of the column 11, a grinding and conveying means 5 for grinding and conveying the machining means 7 in the Z-axis direction is disposed. The grinding and conveying means 5 includes a ball screw 50 having a central axis in the Z-axis direction, a pair of guide rails 51 arranged in parallel with the ball screw 50, A steel plate 53 in which an inner nut is screwed to the ball screw 50 so that the side portion is in sliding contact with the guide rail 51, And the holder 52 is connected to the guide rail 51 so as to rotate the ball screw 50 so that the lift plate 53 is guided by the guide rail 51 And reciprocates in the Z-axis direction, and the machining means 7 held by the holder 54 is ground and transported in the Z-axis direction.

The processing means 7 includes a rotary shaft 70 whose axial direction is the Z axis direction, a housing 71 for rotatably supporting the rotary shaft 70, a motor 72 for rotating the rotary shaft 70, A mount 73 connected to the tip of the rotary shaft 70 and a grinding wheel 74 detachably mounted on the lower surface of the mount 73.

The grinding wheel 74 is composed of an annular wheel base 74b and a plurality of substantially rectangular parallelepipeds of working stone 74a annularly arranged on the bottom surface (free end) of the wheel base 74b. The processed grindstone 74a combines diamond abrasive grains with Vitrified, a glass or ceramic bond. As the tritide, for example, silicon dioxide (SiO2) as a main component and a small amount of an additive may be added to control the melting point. The shape of the machined stone 74a may be an integral annular shape.

1, a flow passage 70a, which is communicated with the process water supply means 8 to be a passage for the process water, is provided so as to penetrate in the axial direction (Z-axis direction) of the rotary shaft 70 The machined water that has passed through the oil passage 70a can be ejected from the wheel base 74b toward the machining stone 74a through the mount 73. [

1 includes a processing water source 80 in which water (for example, pure water) is stored and a pipe 81 connected to the processing water source 80 and communicating with the flow path 70a. The processing water supply means 8 shown in Fig. And an adjusting valve 82 disposed at an arbitrary position on the pipe 81 to adjust the flow rate of the working water.

1 and 2, the grinding apparatus 1 includes a grinding wheel 74a disposed adjacent to the holding table 30 and adapted to grind the workpiece W held by the holding table 30 And a light irradiating means (9) for irradiating a light having a predetermined wavelength to the processed surface (lower surface). 2, the light irradiating means 9 includes, for example, a pedestal 90 having a substantially arc-shaped outer shape and a plurality of (four in the illustrated example) arrays on the upper surface of the pedestal 90 A cleaning water supply portion 92 for supplying cleaning water (for example, pure water) toward the light emitting portion 91 and a cover 93 .

The light emitting portion 91 buried in the concave portion formed on the upper surface of the pedestal 90 is, for example, a low-pressure mercury lamp or UVLED, and can emit light of a predetermined wavelength. You can switch. The light emitting portion 91 is preferably capable of emitting light of two wavelengths and capable of emitting light of a wavelength of 80 to 200 nm and light of a wavelength of 240 to 280 nm. It is more preferable that the light emitting portion 91 can emit light with a wavelength of 365 nm. The light emitting portion 91 in the present embodiment is a double-wavelength LED or a low-pressure mercury lamp and can emit ultraviolet light having a wavelength of 184.9 nm and ultraviolet light having a wavelength of 253.7 nm at the same time.

The plate-like cover 93 is made of, for example, a transparent member such as glass that transmits light produced by the light emitting portion 91, and is fixed on the upper surface of the pedestal 90 so as to cover the light emitting portion 91 . For example, the pedestal 90 is vertically movable by a Z-axis direction moving means (not shown). When the grinding process is performed, the height position of the upper surface of the cover 93 is set to the grinding feed position To the desired height position.

The cleaning water supply unit 92 includes, for example, a cleaning water source (not shown) that reserves water (for example, pure water) and a cleaning water nozzle 920 that communicates with the cleaning water source. The cleaning water nozzle 920 is fixed to the side surface of the pedestal 90 along the pedestal 90 so that the injection port 920a capable of spraying the cleaning water toward the upper surface of the cover 93 is aligned Respectively. The shape and size of the jetting port 920a and the angle with respect to the light emitting portion 91 are set so that jetted cleansing water can be cleaned on the upper surface of the cover 93. As shown in Fig. 2, the jetting ports 920a are formed in a slit shape having a narrow width, and it is preferable that a plurality of jetting ports 920a are provided on the side surface of the cleaning water nozzle 920, but the present invention is not limited thereto. For example, the ejection openings 920a may be formed in a round hole shape, and may be arranged in plural on the side surface of the washing water nozzle 920 or the like. Alternatively, the injection port 920a may be formed in a slit shape having a narrow width extending continuously one on the side surface of the washing water nozzle 920. [

Hereinafter, the respective steps of the machining method and the operation of the grinding apparatus 1 when the machining method according to the present invention is performed using the grinding apparatus 1 shown in Fig. 1 will be described.

A workpiece W having an external shape shown in Fig. 1 having a circular plate shape is a semiconductor wafer formed of, for example, SiC with an arc removed. In the surface Wa of the workpiece W facing downward in Fig. 1, A plurality of devices are formed in a grid-shaped area defined by the planned line, and a protective tape T for protecting the surface Wa is adhered. The back surface Wb of the workpiece W becomes the surface to be ground to be ground by the grinding wheel 74. [ The shape and the type of the workpiece W are not particularly limited and may be suitably changed in relation to the grinding wheel 74, and may be a wafer formed of GaAS or GaN, a wafer formed of a metal or a metal electrode And a wafer partially exposed on the back surface of the wafer.

(1) Maintenance step

First, in the attaching / detaching area A, the workpiece W is placed on the holding surface 300a of the holding table 30 such that the back side Wb is on the upper side. Then, a suction force generated by a suction source (not shown) is transmitted to the holding surface 300a, whereby the holding table 30 holds the workpiece W on the holding surface 300a. The workpiece W is attracted and held along the holding surface 300a which is a gently conical surface.

(2) Processing step

The holding table 30 moves in the + Y direction to the lower side of the processing means 7 by Y-axis direction transfer means (not shown) to transfer the workpiece W held by the grinding wheel 74 and the holding table 30 Are aligned with each other. The position of alignment of the work W is shifted in the + Y direction by a predetermined distance with respect to the center of rotation of the work W so that the rotation locus of the work grindstone 74a Is made to pass through the rotation center. The inclination of the holding table 30 is adjusted such that the holding surface 300a which is a gentle conical surface is parallel to the machining surface which is the lower surface of the working grindstone 74a so that the back surface Wb of the workpiece W And becomes parallel to the machining surface of the machined stone 74a.

3, after the grinding wheel 74 and the workpiece W are aligned, the grinding wheel 74 is rotated in the + direction by the rotation of the rotary shaft 70 by the motor 72, And rotates counterclockwise when viewed from the Z direction. The machining means 7 is sent in the -Z direction by the grinding and conveying means 5 and the grinding wheel 74 provided in the machining means 7 descends in the -Z direction, Is brought into contact with the back surface (Wb) of the work (W). During grinding, since the workpiece W rotates as the holding table 30 rotates in the counterclockwise direction as viewed from the + Z direction, the working grindstone 74a is located on the back surface of the workpiece W 0.0 > Wb < / RTI >

During the grinding process, the process water supply means 8 supplies the process water to the flow path 70a in the rotary shaft 70. 3, the working water supplied to the oil passage 70a passes through the oil passage 73b formed in the mount 73 at regular intervals in the circumferential direction of the mount 73 and further passes through the wheel base 74b From the jetting port 74d of the working stone 74a.

Since the workpiece W is attracted and held along the holding surface 300a on the holding surface 300a which is a gentle conical surface of the holding table 30, the grinding wheel 30 shown in Fig. 4 (a) The machined stone 74a comes into contact with the workpiece W and performs grinding in an area E (hereinafter referred to as machining area E)

The light irradiating means 9 disposed adjacent to the holding table 30 is configured such that when the grinding wheel 74 and the holding table 30 are aligned with each other, Immediately before the grinding wheel 74 enters the workpiece W held by the holding table 30 on the rotational locus of the holding table 30 and the grinding wheel 74, And is disposed immediately before the grindstone 74a enters.

4 (b), the light emitting portion 91 is turned on, and the light emitting portion 91 emits ultraviolet light having a wavelength of 184.9 nm and ultraviolet light having a wavelength of 253.7 nm + Z direction. The irradiated light is irradiated to the lower surface of the processed grindstone 74a immediately before entering the machining area E through the cover 93. [

Ultraviolet light having a wavelength of 184.9 nm is irradiated to the lower surface of the processed grindstone 74a immediately before entering the machining area E so that oxygen molecules in the air existing between the lower surface of the processed grindstone 74a and the light emitting part 91 Absorbs ultraviolet light to generate oxygen atoms in a ground state. The resulting oxygen atoms combine with surrounding oxygen molecules to produce ozone. The ultraviolet light having a wavelength of 184.9 nm decomposes the organic contaminants by breaking the intermolecular bonds and the intermolecular bonds such as organic contaminants caused by the grinding debris adhered to the processed surface of the processed grindstone 74a to excite them. In addition, the generated ozone absorbs ultraviolet light having a wavelength of 253.7 nm, thereby generating active oxygen in the excited state. Since active oxygen or ozone has a high oxidizing power, a hydrophilic group, such as a hydroxyl group, an aldehyde group, and a carboxyl group, having high polarity such as carbon or hydrogen generated on the machined surface of the processed grinding stone 74a, . As a result, the processed grindstone 74a becomes hydrophilic, so that water on the processed surface of the processed grindstone 74a is less likely to become water droplets, and the processed water becomes easier to spread over the entire processed surface of the processed grindstone 74a.

The hydrophilic processed grinding stone 74a enters the processing region E with a large number of processing wafers and grinds the back surface Wb of the workpiece W. [ The machining water enters the contact portion between the back surface Wb of the workpiece W and the machined surface of the machined stone 74a more and more, thereby suppressing the generation of frictional heat occurring at the contact portion.

As shown in Fig. 5, during the grinding process, the rinsing water supply unit 92 supplies rinsing water toward the upper surface of the cover 93. As shown in Fig. That is, washing water is supplied to the washing water nozzle 920 from a washing water source (not shown), and the washing water is ejected from the ejection opening 920a toward the outside of the nozzle to reach the cover 93 so as to draw a parabola. The cleaning water is then rectified appropriately to remove dust such as grinding debris adhering to the cover 93 so that the light generated by the light emitting portion 91 during grinding is processed So that the surface is properly irradiated.

A method of processing a workpiece according to the present invention includes a holding step of holding a workpiece W with a holding table 30 having a holding surface 300a for holding the workpiece W, And a machining step of grinding the workpiece W with the machining means 7 including the machining stone 74a having the abrasive grains bonded to the workpiece W in a non-trivial manner. In the machining step, the machining water is supplied to the workpiece W By irradiating light of a predetermined wavelength from the light irradiating means 9 to the machining surface of the machining stone 74a, it is possible to irradiate the contact surface between the back surface Wb of the work W and the machining surface of the machining stone 74a It is possible to suppress the generation of the frictional heat generated at the contact portion by putting more processing water into the abrasive grains 74a, thereby suppressing the abrasion of the processed grindstone 74a (abnormal abrasion beyond abrasion that prompts proper self sharpening). It is also possible to effectively eliminate the grinding debris generated at the contact portion between the back surface Wb of the workpiece W and the machined surface of the machining stone 74a by the machining water. In addition, since the machining wheel 74a effectively supplies the machining water to the machining area E for grinding the workpiece W due to the hydrophilization of the machined stone 74a, the occurrence of wafer burning Deterioration of the machining quality of the workpiece W can be prevented, and it is possible to smoothly perform stable grinding even on a wafer formed with a machining process.

The inventor of the present invention conducted the following Experiment 1 in order to verify the effect of light irradiation at a wavelength of 365 nm on the machined surface of the processed grinding stone in the processing step of the processing method according to the present invention. In Experiment 1, a soda glass plate having a thickness of 10 mm was used as a workpiece W of a circular plate shape. The working stone 74a of the grinding wheel 74 employed a diamond abrasive grains having a grain size of # 1000 bonded with a non-trippled bond.

In Experiment 1, after the holding step, the processing step was carried out under the processing conditions shown below.

Rotation speed (rpm) of grinding wheel 74: 2000 rpm

(Rpm) of the holding table 30: 300 rpm

Grinding feed rate (descending speed) of the grinding wheel 74: 0.5 m / sec

In Experiment 1, ultraviolet light having a wavelength of 365 nm was irradiated onto the working grindstone 74a of the grinding wheel 74 by using LED light as the light emitting portion 91 of the light irradiating means 9 shown in Fig. While the irradiation of the ultraviolet light to the lower surface of the working grindstone 74a from the light emitting portion 91 is stopped while the work W is grinded to 50 mu m Grinding, and grinding with irradiation of such ultraviolet light and grinding without irradiation of ultraviolet light were repeatedly performed continuously. The supply of the machining wheel 74a of the machining water and the like were carried out in the same manner as the machining step described above.

6 is a plot of the measured values obtained in Experiment 1. In the plot diagram P1, the abscissa indicates the machining of the workpiece W by 50 占 퐉 of the grinding wheel 74 for each grinding, (Mu m) of the grinding wheel 74a and the vertical axis represents the maximum working load N that the grinding wheel 74 has received during grinding the workpiece W by 50 mu m. The consumed amount of the working grindstone 74a and the maximum working load value received by the grinding wheel 74 when grinding is performed while irradiating the measured ultraviolet light are represented by a round point in the plot P1, The graph G1 shows the trend easily. The consumed amount of the working grindstone 74a and the maximum working load value received by the grinding wheel 74 when grinding was performed without irradiating the measured ultraviolet light are represented by triangles in the plot P1, And the graph (G2) indicated by the dashed line shows the trend easily.

As can be read from the plot P1, in the case of grinding the workpiece W while irradiating ultraviolet light having a wavelength of 365 nm onto the lower surface of the working grindstone 74a of the grinding wheel 74, The consumed amount of the processed grindstone 74a and the load exerted by the grinding wheel 74 upon grinding can be suppressed to a low level as compared with the case where the grinding wheel 74 is not irradiated. If the working load received by the grinding wheel 74 can be suppressed to such a low level, the load applied to the motor 52 of the grinding and conveying means 5 shown in Fig. 1 may be reduced, or the load applied to the ball screw 50 It is possible to prevent backlash from occurring. When grinding is performed while irradiating the lower surface of the working stone 74a of the grinding wheel 74 with ultraviolet light having a wavelength of 365 nm in the case of comparing the working load received by the grinding wheel 74 to the dynamic load, The consumed amount of the machining stone 74a can be suppressed to about 20% lower than in the case where the machined stone 74a is not used.

(Embodiment 2)

The cutting apparatus 2 shown in Fig. 7 rotates the cutting blade 210 provided in the processing means 21 with respect to the workpiece W held on the holding surface 200a of the holding table 20, Thereby performing cutting processing.

On the base 2A of the cutting apparatus 2, a cutting / conveying means 22 for reciprocating the holding table 20 in the cutting / conveying direction (X-axis direction) is disposed. The cutting and conveying means 22 includes a ball screw 220 having an axis in the X axis direction, a pair of guide rails 221 arranged in parallel with the ball screw 220, And a movable plate 223 in which the nut is screwed to the ball screw 220 and the bottom portion thereof is in sliding contact with the guide rail 221. When the motor 222 rotates the ball screw 220, the movable plate 223 is guided by the guide rails 221 to move in the X-axis direction, and the holding plate 223, which is disposed on the movable plate 223, (20) also moves in the X-axis direction.

The holding table 20 disposed on the movable plate 223 is constituted by a suction part 200 which is formed in a circular shape and whose external shape is a porous member and which suctions the workpiece W, And a frame 201 which is provided with a frame. The adsorption unit 200 communicates with a suction source (not shown) and sucks and holds the workpiece W on the holding surface 200a, which is the exposed surface of the adsorption unit 200. [ The holding table 20 is rotatable by a rotating means 202 disposed on the bottom surface side of the holding table 20. [ At the periphery of the holding table 20, four fixed clamps 204 are arranged at equal intervals in the illustrated example.

An indexing conveying means 23 for reciprocating the processing means 21 in the Y-axis direction is disposed from the center on the base 2A to the rear side (+ Y direction side). The indexing and conveying means 23 includes a ball screw 230 having an axis in the Y axis direction, a pair of guide rails 231 disposed in parallel with the ball screw 230, And a movable portion 233 whose inner portion is screwed to the ball screw 230 so that the bottom portion thereof makes sliding contact with the guide rail 231. When the motor 232 rotates the ball screw 230, the movable portion 233 is guided by the guide rail 231 and moves in the Y-axis direction. As the movable portion 233 moves, Is moved in the Y-axis direction.

An infeed conveying means 24 for moving the processing means 21 up and down in the Z-axis direction is provided on the side of the column 234 on the -X direction side, with a column 234 integrally standing on the movable portion 233 Respectively. The infeed and feed means 24 includes a ball screw 240 having an axis in the Z-axis direction, a pair of guide rails 241 disposed in parallel with the ball screw 240, And a support member 243 in which an inner nut is screwed to the ball screw 240 and the side portion is in sliding contact with the guide rail 241. When the motor 242 rotates the ball screw 240, the support member 243 is guided by the guide rail 241 and moves in the Z-axis direction, 21) is fed and fed in the Z-axis direction.

The processing means 21 includes a spindle 211 whose axial direction is orthogonal to the moving direction (X-axis direction) of the holding table 20 in the horizontal direction (Y-axis direction) A motor (not shown) which is accommodated in the housing 212 and rotatably drives the spindle 211; a cutting blade 210 mounted on the tip of the spindle 211 in the -Y direction; And the cutting blade 210 also rotates at a high speed by the motor driving the spindle 211 to rotate.

On the side surface of the housing 212, an aligning means 25 for detecting the position of cutting the cutting blade 210 by picking up the workpiece W is disposed. The alignment means 25 is provided with an alignment camera 250 for picking up a surface to be cut of the workpiece W. Based on the image obtained by the alignment camera 250, The line to be divided S to be cut of the workpiece W can be detected.

The cutting blade 210 shown in Fig. 8 is, for example, a washer-shaped blade having an annular outer shape having a mounting hole at the center thereof, and the whole of the blade is a working stone. For example, the cutting blade 210 is formed by bonding diamond abrasive grains with non-tritide, which is a vitreous or ceramic bonding agent. As the non-tritide, for example, silicon nitride (SiO2) . The cutting blade 210 is sandwiched from both sides in the Y axis direction by a mounting flange 218 and a mount flange (not shown), and is attached to the spindle 211 by fastening by a fixing nut 217. The cutting blade 210 may be a hub-type cutting blade provided so as to protrude in the radially outward direction from the base made of aluminum or the like.

As shown in Figs. 7 and 8, the processing means 21 includes a blade cover 219 covering the cutting blade 210, for example. The blade cover 219 has an opening for accommodating the cutting blade 210 at a substantially central portion thereof and is attached to the housing 212 so that the cutting blade 210 is positioned in the opening, Can be covered from above.

At the end of the blade cover 219 in the -X direction, the support block 213 is fixed by an adjusting screw 213a movably in the Z-axis direction. In the support block 213, a pair of process water nozzles 214 are fixed. Process water is supplied to the pair of the process water nozzles 214 from the supply hose 213b through the support block 213. [ The pair of working water nozzles 214 extend parallel to each other in the + X direction so as to sandwich the lower portion of the cutting blade 210 from both sides of the cutting blade 210. A plurality of slits are provided in alignment with a plurality of X-axis directions at positions corresponding to the cutting blades 210 on the tip side of a pair of the process water nozzles 214. Processed water is sprayed from the side by a plurality of slits, The contact portion between the workpiece 210 and the workpiece W is cooled. A pair of the droplet cover 213c for guiding the sprayed working water to the -X direction side is disposed at the lower end of the support block 213.

At the end in the + X direction of the blade cover 219, a worker male block 215 is fastened by an adjusting screw 215a so as to be slidable in the Y-axis direction. 8, a machining water nozzle 216 for spraying machining water to the cutting blade 210 is disposed in the machining water block 215 from the outer circumferential direction of the cutting blade 210. As shown in Fig. A supply water hose 215b communicates with the upper end of the process water nozzle 216. The process water nozzle opening 216a which is the lower end of the process water nozzle 216 opens toward the front end face . The machining water is sprayed to the cutting blade 210 from the outer circumferential direction by the machining water nozzle 216 so that the machining water is allowed to flow into the rotating cutting blade 210 and the machining water is supplied to the contact portion between the cutting blade 210 and the workpiece W And is extruded toward the -X direction together with the generated cutting debris, whereby the contact portion is cleaned and cooled.

The cutting apparatus 2 has a light irradiation means 4 for irradiating a light of a predetermined wavelength to a machining surface (front end surface of the blade) of the cutting blade 210. The light irradiating means 4 includes a light emitting portion 40 composed of a low pressure mercury lamp or UV LED and a power supply 41 for switching on / off of the light emitting portion 40, for example.

The light emitting portion 40 is disposed on the machining water block 215 so as to be opposed to the machining surface of the cutting blade 210 from the outside in the radial direction and is positioned higher than the machining water jetting opening 216a of the machining water nozzle 216 Location. The light emitting portion 40 is preferably capable of emitting light having two wavelengths and capable of emitting light having a wavelength of 80 nm or more and 200 nm or less and light having a wavelength of 240 nm or more and 280 nm or less. It is more preferable that the light emitting portion 40 can emit light having a wavelength of 365 nm. The light emitting portion 40 in the present embodiment is a two-wavelength LED or a low-pressure mercury lamp, and can emit ultraviolet light having a wavelength of 184.9 nm and ultraviolet light having a wavelength of 253.7 nm at the same time.

Hereinafter, the respective steps of the machining method and the operation of the cutting apparatus 2 when the machining method according to the present invention is performed using the cutting apparatus 2 shown in Fig. 7 will be described.

A workpiece W having an external shape shown in Fig. 1 having a circular plate shape is a semiconductor wafer formed of, for example, SiC with an arc removed. In Fig. 7, a surface Wa of a workpiece W, A plurality of devices D are formed in a lattice-shaped region defined by the planned line S. A dicing tape T1 having a larger diameter than the workpiece W is adhered to the back surface Wb of the workpiece W. [ An annular frame F having a circular opening is adhered to the outer peripheral region of the adhered surface of the dicing tape T1 and the work W is fixed to the annular frame F through the dicing tape T1 And is in a state ready for handling through the annular frame F. As shown in Fig. The shape and the type of the workpiece W are not particularly limited and may be suitably changed in relation to the cutting blade 210. A wafer formed of GaAS or GaN or a wafer or metal electrode made of a metal The wafer partially exposed on the back side of the wafer is also included.

(1) Maintenance step

The workpiece W is placed on the holding surface 200a of the holding table 20 with the dicing tape T1 side down. Then, a suction force generated by a suction source (not shown) is transmitted to the holding surface 200a, whereby the workpiece W is held by the holding table 20 in a suctioned state. Further, the annular frame F is fixed by each of the fixing clamps 204. [

(2) Processing step

The work W held by the holding table 20 is sent in the -X direction by the cutting and conveying means 22 so that the coordinates in the Y-axis direction of the line S to be divided, in which the cutting blade 210 is to be inserted The position is detected by the alignment means 25. Further, the machining means 21 is driven in the Y-axis direction by the indexing and conveying means 23, and alignment in the Y-axis direction of the to-be-divided line S to be cut and the cutting blade 210 is performed .

The cutting blade 210 is moved away from the back surface Wb of the workpiece W and the dicing is carried out by the cutting and dropping means 24, The processing means 21 is positioned at a predetermined height position reaching the tape T1. Further, as the motor (not shown) rotates and drives the spindle 211, the cutting blade 210 rotates at a high speed in the clockwise direction as viewed from, for example, the -Y direction.

The holding table 20 for holding the workpiece W is further fed out in the -X direction at a predetermined cutting feed rate so that the cutting blade 210 rotating at a high speed is fed into the workpiece W, S to cut the workpiece W. During the cutting process, the machining water is injected from the side of the cutting blade 210 to the contact area between the cutting blade 210 and the workpiece W by the machining water nozzle 214, Cooling and cleaning are performed.

The light emitting portion 40 is turned ON by the power source 41 and the ultraviolet light having a wavelength of 184.9 nm and the ultraviolet light having a wavelength of 253.7 nm are emitted from the cutting blade 210 And irradiates the machining surface of the cutting blade 210 rotating from the outer circumferential direction.

The machining water is sprayed on the machining surface of the cutting blade 210 from the outer circumferential direction of the cutting blade 210 by the machining water nozzle 216 so that the machining surface of the cutting blade 210, And is extruded toward the -X direction together with the processing debris generated at the contact portion between the cutting blade 210 and the workpiece W, thereby cooling and cleaning the contact portion.

Ultraviolet light having a wavelength of 184.9 nm is irradiated onto the machining surface of the cutting blade 210 immediately before the machining water nozzle 216 is sprayed with the machining water so as to be present between the tip end surface of the cutting blade 210 and the light emitting portion 40 Oxygen molecules in the air absorb ultraviolet light to generate oxygen atoms in a ground state. The resulting oxygen atoms combine with surrounding oxygen molecules to produce ozone. The ultraviolet light having a wavelength of 184.9 nm decomposes organic contaminants by cutting off intermolecular bonds and intermolecular bonds such as organic contaminants due to cutting debris adhering to the processing surface of the cutting blade 210 and bringing them into an excited state. In addition, the generated ozone absorbs ultraviolet light having a wavelength of 253.7 nm, thereby generating active oxygen in the excited state. Since the generated active oxygen or ozone has a high oxidizing power, a hydrophilic group having a large polarity such as a hydroxyl group, an aldehyde group, and a carboxyl group, which is bonded to carbon or hydrogen generated on the machining surface of the cutting blade 210, And formed on the machined surface. As a result, the cutting blade 210 becomes hydrophilic, so that the processing water on the machining surface of the cutting blade 210 is less likely to become water droplets, and the machining water on the machining surface of the cutting blade 210 can easily spread.

The hydrophilized cutting blade 210 infiltrates into the back surface Wb of the workpiece W accompanied by a lot of machining water jetted from the machining water nozzle 216. The machining water enters the contact portion between the back surface Wb of the workpiece W and the machining surface of the cutting blade 210 more and more, and the generation of frictional heat occurring at the contact portion is suppressed.

When the workpiece W advances in the -X direction to a predetermined position in the X-axis direction where the cutting blade 210 cuts the line to be divided S multiple times, the workpiece W in the -X direction is cut The cutting blade 210 is separated from the workpiece W and the holding table 20 is sent out in the + X direction to return to the original position. Then, the cutting blades 210 are indexed and transferred in the Y-axis direction at intervals of the adjacent lines to be divided S, and the same cutting is sequentially performed to cut all the lines S to be divided in the same direction. When the same cutting is performed after rotating the holding table 20 by 90 degrees, all the lines to be divided S are fully cut in the longitudinal and transverse directions.

A method of processing a workpiece according to the present invention includes a holding step of holding a workpiece W in a holding table 20 having a holding surface 200a for holding a workpiece W, And a machining step of machining the workpiece W with a machining means 21 including a cutting blade 210 in which the abrasive grains are combined with non-trivia. In the machining step, And irradiates light of a predetermined wavelength from the light irradiating means 4 to the machining surface of the cutting blade 210 so that the back surface Wb of the workpiece W due to hydrophilization of the cutting blade 210, And more abrasion of the cutting blade 210 can be suppressed by suppressing the generation of frictional heat occurring at the contact portion by putting more processing water in the contact portion between the cutting blade 210 and the machining surface of the cutting blade 210. Further, Foot of wafer burning by rise It is possible to prevent the deterioration of the quality of the work such as the life of the workpiece W, In addition, the cutting debris generated at the contact portion between the back surface Wb of the workpiece W and the machining surface of the cutting blade 210 can be effectively eliminated by the machining water.

1: Grinding apparatus 10: Base 11: Column 12: Input means
30: holding table 300: suction part 300a: holding surface 301: frame
31: Cover 31a: Crease box cover
5: Grinding and conveying means 50: Ball screw 51: Guide rail 52: Motor 53: Steel plate 54:
7: Machining means 70: Rotation shaft 70a: Flow path 71: Housing 72: Motor 73: Mount 74: Grinding wheel 74a: Machining wheel 74b:
8: Process water supply means 80: Process water source 81: Piping 82: Adjustment valve
9: light irradiation means 90: pedestal 91: light emitting portion 92: cleansing water supply portion 920: cleansing water nozzle 920a: jetting port 93: cover
W: workpiece Wa: surface of the workpiece Wb: rear surface of the workpiece T: protective tape A: attaching / detaching area B:
P1: plot
2: Cutting device 2A: Base
20: holding table 200: suction part 200a: holding surface 201: frame 202: rotating means 204: fixed clamp
21: machining means 210: cutting blade 211: spindle 212: housing 218: detachable flange 217:
The present invention relates to a method of manufacturing an optical disk, which comprises a blade cover, a blade cover, a support block, an adjustment screw, a supply hose, a droplet cover,
25: Alignment means 250: Alignment camera
22: cutting and conveying means 220: ball screw 221: guide rail 222: motor 223: movable plate
23: indexing feed means 230: ball screw 231: guide rail 232: motor
233: moving part 234: column
24: Infeed feed means 240: Ball screw 241: Guide rail 242: Motor
243: Support member
4: light irradiation means 40: light emitting portion 41: power source
W: workpiece Wa: surface of the workpiece Wb: back surface of the workpiece S: expected line to be divided D: device T1: dicing tape F:

Claims (3)

As a processing method of a workpiece,
A holding step of holding a workpiece with a holding table having a holding surface for holding the workpiece;
After the holding step, a processing step of machining a workpiece with machining means including a machining wheel having abrasive grains bonded with non-trivia
Lt; / RTI >
Wherein the machining step supplies the machining water to the workpiece and irradiates light of a predetermined wavelength from the light irradiation means to the machined surface of the machined stone. The method according to claim 1,
Wherein the machining means has a cutting blade having the machining wheel,
And cutting the workpiece with the cutting blade in the machining step. The method according to claim 1,
Wherein the machining means includes a grinding wheel having the machining wheel,
Wherein the grinding wheel grinds the workpiece in the machining step.

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