TWI810334B - Deep-cut and slow-feed grinding method - Google Patents

Abstract

The object of the present invention is to form a surface to be ground of a workpiece into a beautiful surface with few irregularities in a creep feed grinding method. The solution, the deep-cut and slow-feed grinding method, is that the rotating shaft (70) of the grinding means (7) is more inclined than the Z-axis direction for the holding surface (300a) of the platform (30), and the grinding stone (741) The side with the smallest distance between the lower surface and the holding surface (300a) is set as the front of the grinding wheel (74), and the side with the largest distance between the lower surface of the grinding stone (741) and the holding surface (300a) is set as the grinding wheel. Rear of (74), with: Use the Z-axis direction moving means (5) to position the lower surface of the front grinding stone (741) lower than the upper surface of the plate-shaped workpiece (W) held on the platform (30), and use the Y-axis direction moving means ( 14), the project of positioning the held plate-shaped workpiece (W) on the rear side of the grinding stone (741) in front; and After the positioning project, utilize the Y-axis direction moving means (14) to make the platform (30) move to the direction from the rear of the grinding wheel (74) towards the front for the grinding means (7), and use the grinding whetstone ( 741) to grind the bottom and inner side of the plate-shaped workpiece (W).

Description

Deep-cut and slow-feed grinding method

The invention relates to a deep-cut slow-feed grinding method for grinding plate-like workpieces.

Use the holding platform to attract and hold the plate-shaped workpiece with electrodes, rotate the grinding wheel with the grinding stone arranged in the ring, and deep-cut and slow-feed the upper surface of the plate-shaped workpiece, if the grinding stone is positioned at the predetermined position If the holding platform holding the plate-shaped workpiece is moved toward the grinding stone in the Y-axis direction parallel to the holding surface direction of the holding platform, and the outer peripheral surface (outer surface) of the grinding stone is used for grinding, a large The grinding force (for example, refer to Patent Document 1 or 2). [Prior Art Literature] [Patent Document]

[Patent Document 1] Japanese Patent Laid-Open No. 2010-016181 [Patent Document 2] Japanese Unexamined Patent Publication No. 2009-69759

(Problem to be solved by the invention)

However, if the plate-shaped workpiece is shallowly ground by grinding the outer peripheral surface of the whetstone, unevenness or the like is generated on the surface to be ground of the workpiece, and the surface to be ground may be rough. Therefore, in the deep-cut creep-feed grinding method, there is a problem of making the ground surface of the workpiece a beautiful surface after grinding.

Also, if deep-cutting and slow-feeding grind a long plate-shaped workpiece, due to the consumption of the grinding stone, the thickness of the place where the grinding stone starts to enter the workpiece and the thickness of the place where the grinding stone leaves the workpiece after the end of grinding will be different. A case where a large difference in thickness occurs. Therefore, when performing deep-cut creep-feed grinding on a long plate-shaped workpiece, there is a problem of reducing the difference in thickness of the surface to be ground. (means to solve the problem)

The present invention to solve the above-mentioned problems is a deep-cut and creep-feed grinding method in which a plate-shaped workpiece is ground with the grinding stone positioned at a lower position than the upper surface of the plate-shaped workpiece using a grinding device. Deep-cut and slow-feed grinding method, the grinding device is equipped with: A holding platform having a holding surface for holding a plate-shaped workpiece; Grinding means, which is to install a grinding wheel ring-shaped with a grinding stone on a fixed stand connected to the front end of the rotating shaft, rotate the rotating shaft, and grind a plate-shaped workpiece with the grinding stone; Y-axis direction moving means, which is to move the holding platform and the grinding means relatively in the Y-axis direction parallel to the direction of the holding surface; and The Z-axis direction movement means moves the grinding means in the Z-axis direction perpendicular to the Y-axis direction and perpendicular to the holding surface, Its characteristics are: The rotation axis is more inclined than the Z-axis direction with respect to the holding surface, and the side where the distance between the lower surface of the grinding stone and the holding surface is minimized is set as the front of the grinding wheel, and the side of the grinding stone is The side at which the distance between the lower surface and the holding surface becomes the largest is set as the rear of the grinding wheel, have: The positioning process is to use the moving means in the Z-axis direction to position the lower surface of the front grinding stone lower than the upper surface of the plate-shaped workpiece held on the holding platform, and to use the moving means in the Y-axis direction to place the The plate-shaped workpiece held on the holding platform is positioned on the rear side of the front grinding stone; and Grinding process, after the positioning process, using the Y-axis direction moving means to move the holding platform to the direction from the rear of the grinding wheel towards the front of the grinding means, with the front Grinding the bottom and inner side of the whetstone to grind plate-shaped workpieces.

In the deep-cut and slow-feed grinding method of the present invention, it has: Measuring process, which is to measure the upper surface height of the plate-shaped workpiece immediately after the deep-cut and creep-feed grinding is started by means of the upper surface height measurement means arranged on the outer side of the aforementioned annular grinding stone; and In the correction process, the grinding means is moved in the Z-axis direction according to the measurement value measured in the measurement process, and the difference in thickness of the plate-shaped workpiece after grinding is reduced.

In the deep-cut creep grinding method of the present invention, in the positioning process, it is desirable to position the lower surface of the rear grinding stone at a lower position than the upper surface of the plate-shaped workpiece held on the holding table. [Effect of the invention]

In the deep-cut and slow-feed grinding of the present invention, the rotation axis is more inclined than the Z-axis direction with respect to the holding surface, and the side where the distance between the bottom of the grinding stone and the holding surface is the smallest is set as the front of the grinding wheel, and the grinding The side where the distance between the bottom of the whetstone and the holding surface becomes the largest is set as the rear of the grinding wheel, have: Positioning process, which is to use the Z-axis direction movement means to position the lower side of the grinding stone in front to be lower than the upper surface of the plate-shaped workpiece held on the holding platform, and use the Y-axis direction movement means to position the workpiece held on the holding platform. The plate-shaped workpiece of the platform is positioned on the rear side than the front grinding stone; and Grinding process, which is after the positioning process, uses the Y-axis direction movement means to move the holding platform to the direction from the rear of the grinding wheel to the front of the grinding means to grind the bottom and inner side of the grinding stone in front to grind plate workpieces, Thereby, the upper surface of the plate-shaped workpiece after grinding can be made into a beautiful ground surface without unevenness or the like.

The deep-cut and slow-feed grinding of the present invention has: Measuring process, which is to measure the upper surface height of the plate-shaped workpiece immediately after the deep-cut and creep-feed grinding is started by using the upper surface height measurement means arranged on the outer side of the ring-shaped grinding stone; and Correction process, which is to move the grinding means in the Z-axis direction according to the measurement value measured in the measurement process, and reduce the thickness difference of the plate-shaped workpiece after grinding, Thereby, the difference in thickness of the plate-shaped workpiece W after grinding can be reduced.

In the positioning process, the lower surface of the rear grinding stone is positioned lower than the upper surface of the plate-shaped workpiece held on the holding platform, In this way, first, the plate-shaped workpiece is largely ground with the outer surface and lower surface of the rear grinding stone, and further, the outer surface and lower surface of the rear grinding stone are ground with the inner surface and lower surface of the front grinding stone. The upper surface of the plate-shaped workpiece to be ground below can make the upper surface of the plate-shaped workpiece after grinding into a beautiful ground surface without unevenness or the like.

The grinding device 1 shown in FIG. 1 is a device for grinding a plate-shaped workpiece W held on a holding platform 30 by a rotating grinding wheel 74. It has a device bottom 10 extending in the Y-axis direction, and a The pillar 11 is erected on the rear side (+Y direction side) of the device bottom 10 . The front side (-Y direction side) of the device bottom 10 of the grinding device 1 is a loading and unloading area for loading and unloading the plate-shaped workpiece W on the holding platform 30, and the rear part of the device bottom 10 is where the workpiece W is loaded and unloaded by the grinding means 7. Grinding area for grinding the plate-shaped workpiece W held on the holding table 30 .

The plate-shaped workpiece W shown in detail in FIG. 2 includes, for example, a rectangular substrate W1 made of PCB or the like, and a rectangular wafer W2 whose base material is silicon or the like. The lower surface of the wafer W2 is bonded to the upper surface of the substrate W1. Devices not shown are formed on the upper surface of the wafer W2. On the surface of the device, a plurality of cylindrical electrodes E are respectively erected. The electrode E is composed, for example, of copper as a main component. The upper surface of the wafer W2 is sealed with a resin layer J such as epoxy resin, and the upper ends of the electrodes E are covered with the resin layer J.

The upper surface of the resin layer J is the upper surface Wa to be the plate-shaped workpiece W, and the lower surface of the substrate W1 is the lower surface Wb to be the plate-shaped workpiece W. The lower surface Wb of the plate-shaped workpiece W may be protected by affixing, for example, a not-shown protective tape. As an example of the size of the rectangular plate-shaped workpiece W, it is 600 mm in length and 300 mm in width.

For example, the holding platform 30 shown in FIG. 1 includes a suction unit 300 made of a porous member or the like, which suctions a plate-shaped workpiece W, and a frame body 301 which supports the suction unit 300 . The suction part 300 is connected to an unillustrated suction source such as a vacuum generator, and the suction force generated by the suction source will be transmitted to the holding surface 300a of the exposed surface of the suction part 300, whereby the holding platform 30 can be moved The plate-shaped workpiece W is sucked and held on the holding surface 300a. Furthermore, the holding platform 30 is surrounded by a cover 39 and is rotatable around the axis in the Z-axis direction by the rotating means 34 disposed below the holding platform 30 . In addition, since the rotating means 34 is stopped during grinding processing, it does not need to be provided.

Below the holding platform 30 , the cover 39 and the bellows cover 39 a connected to the cover 39 is provided a Y-axis direction moving means 14 for moving the holding platform 30 in the Y-axis direction parallel to the direction of the holding surface 300 a. The Y-axis direction moving means 14 is provided with: a ball screw 140 having an axis in the Y-axis direction, a pair of guide rails 141 arranged parallel to the ball screw 140, a motor 142 connected to the ball screw 140 to rotate the ball screw 140, and The nut provided inside is screwed to the ball screw 140 and the bottom of the movable plate 143 slides on the guide rail 141 . Once the motor 142 rotates the ball screw 140 , the movable plate 143 is guided on the guide rail 141 accordingly. Moving in the Y-axis direction, the holding platform 30 disposed on the movable plate 143 via the rotating means 34 moves in the Y-axis direction. The bellows cover 39 a expands and contracts in the Y-axis direction as the holding platform 30 moves.

A Z-axis direction moving means 5 for moving the grinding means 7 in the Z-axis direction perpendicular to the Y-axis direction and perpendicular to the holding surface 300 a of the holding table 30 is arranged in front of the pillar 11 . The Z-axis direction moving means 5 is provided with: a ball screw 50 having an axis in the Z-axis direction, a pair of guide rails 51 arranged parallel to the ball screw 50 , and a motor 52 connected to the upper end of the ball screw 50 to rotate the ball screw 50 , and the internal nut will be screwed on the ball screw 50 and the side will slide on the lifting plate 53 of the guide rail 51. Once the motor 52 rotates the ball screw 50, the lifting plate 53 will be guided on the guide rail 51 accordingly. While moving back and forth in the Z-axis direction, the grinding means 7 fixed to the lifting plate 53 will be ground and fed in the Z-axis direction.

Grinding means 7 is equipped with: The axial direction is more inclined than the Z-axis direction with respect to the holding surface 300a of the holding platform 30; a casing (housing) 71 that rotatably supports the rotating shaft 70; a motor 72 that rotatably drives the rotary shaft 70; A circular plate-shaped fixed stand (mount) 73 connected to the front end of the rotating shaft 70; The grinding wheel 74 is mounted on the lower side of the fixed stand 73; and The side of the support case 71 is fixed to a holder 75 of the lifting plate 53 of the moving means 5 in the Z-axis direction.

Since the rotating shaft 70 is more inclined than the Z-axis direction, the ring-shaped grinding stone 741 is also in a state of being more inclined than the Z-axis direction. Moreover, the side (the side in the −Y direction) on which the distance between the lower surface 741b of the grinding stone 741 shown in FIG. 741 ahead). Furthermore, the side (the side in the +Y direction in FIG. 2 ) where the distance between the lower surface 741b of the grinding stone 741 and the holding surface 300a is the largest is defined as the rear of the grinding wheel 74 (the rear of the grinding stone 741 ). In addition, in FIG. 2, a part of each component of the grinding apparatus 1 is simplified and abbreviate|omitted and shown.

The inclination angle of the rotation shaft 70 from the Z-axis direction is a slight angle, and the angle is set to a predetermined value corresponding to the diameter of the grinding wheel 74, for example. The inclination angle of the rotating shaft 70 from the Z-axis direction, for example, when the diameter (mm) of the grinding wheel 74 is Φ300, is set at the height position of the lower surface 741b of the front grinding stone 741 and the lower surface of the rear grinding stone 741. The height position difference L0 of 741b is, for example, an angle of 20 μm to 30 μm. In addition, the inclination angle of the rotating shaft 70 from the Z-axis direction is set so that the height position of the lower surface 741b of the front grinding stone 741 and the height position of the rear grinding stone 741 are set when the diameter (mm) of the grinding wheel 74 is Φ500, for example. The difference L0 of the height position of the lower surface 741b is, for example, an angle of 30 μm to 50 μm. In addition, the holding surface 300a of the holding table 30 is ground with the lower surface 741b of the grinding stone 741 in the state where the rotating shaft 70 is inclined, and after the lower surface 741b is parallel to the holding surface 300a, the plate-shaped workpiece W is held on the holding surface 300a. , to grind with the following 741b of the grinding whetstone 741.

The grinding wheel 74 is provided with an annular wheel base 740 , and a plurality of grinding stones 741 having a substantially rectangular parallelepiped shape are arranged annularly in an area on the outer peripheral side of the bottom surface of the wheel base 740 . The grinding stone 741 is shaped by fixing diamond grains and the like with a predetermined binder. In addition, the grinding stone 741 is used for grinding a plate-shaped workpiece W provided with an electrode E made of copper or the like, for example, and the ratio or size of pores in the grinding stone is larger than that of a normal grinding stone. The reason why the ratio or size of the pores in the grinding stone 741 is set to be large is because if the electrode E is ground with a normal grinding stone, the copper constituting the electrode E is likely to clog the pores of the grinding stone, so To prevent this clogging. On the other hand, since the grinding stone 741 has a large ratio or size of voids, the amount of wear accompanying the grinding of the plate-shaped workpiece W is larger than that of a normal grinding stone.

For example, in the inside of the rotating shaft 70, a flow path (not shown) that communicates with the grinding water supply source and becomes a passage of grinding water is formed through the axial direction of the rotating shaft 70, and the flow path is opened so that it can be used in the grinding process. The bottom surface of the shaving wheel 74 sprays grinding water toward the grinding stone 741 .

As shown in FIG. 1 , above the moving path of the holding table 30 , a top surface height measuring means 38 for measuring the height of the top surface Wa of the plate-shaped workpiece W held on the holding table 30 by a contact method is arranged. The upper surface height measuring means 38 is equipped with a contact 380 at its front end that moves up and down to contact the surface to be measured. The contact 380 is, for example, formed in the shape of a sharp head whose diameter gradually decreases downward. The contact head 380 is supported by the arm part 381, and the arm part 381 can push the contact head 380 against the surface to be measured with an appropriate force by the pressing force generated by the spring built in the arm part 381. While deep-cut and creep-feed grinding is being performed, the upper surface height measuring means 38 measures the height of the upper surface Wa of the plate-shaped workpiece W outside the annular grinding stone 741 of the grinding means 7 . In addition, the upper surface height measuring means may be a non-contact type which irradiates the upper surface Wa of the plate-shaped workpiece W with measurement light.

As shown in FIG. 1 , the grinding apparatus 1 is a control means 9 that includes a memory unit 91 including a CPU, a memory, and the like, and controls the entire apparatus. The control means 9 is electrically connected to the moving means 5 in the Z-axis direction and the moving means 14 in the Y-axis direction through unshown wiring. The moving action and positioning height of the cutting means 7 in the Z-axis direction, and the moving speed of the holding platform 30 by the moving means 14 in the Y-axis direction, etc.

For example, the motor 52 of the above-mentioned Z-axis direction moving means 5 is a pulse motor operated by a drive pulse supplied from a pulse oscillator not shown. The control means 9 counts the number of drive pulses supplied to the Z-axis direction moving means 5 . Identify the height position of the grinding means 7. In addition, the motor 52 of the Z-axis direction moving means 5 may be used as a servo motor, and a rotary encoder may be connected to the servo motor. The rotary encoder is connected to the control means 9 which also functions as a servo amplifier, and after an operation signal is supplied to the servo motor from the control means 9, an encoder signal (number of revolutions of the servo motor) is output to the control means 9. The control means 9 calculates the movement amount of the grinding means 7 in the Z-axis direction according to the received encoder signal, and identifies its height position.

(Embodiment 1 of deep-cut creep grinding method) Hereinafter, each process related to the deep-cutting and creep-feed grinding of the plate-shaped workpiece W by the grinding device 1 will be described with reference to FIGS. 1 to 4 .

(1) Positioning engineering First, the plate-shaped workpiece W shown in FIGS. 1 and 2 is placed on the holding surface 300 a of the holding platform 30 with the resin layer J facing upward in the loading and unloading area on the bottom 10 of the apparatus. Then, the suction force generated by the operation of an unillustrated suction source connected to the holding table 30 is transmitted to the holding surface 300 a, and the plate-shaped workpiece W is sucked and held by the holding table 30 .

The holding platform 30 that attracts and holds the plate-shaped workpiece W moves from the loading and unloading area on the bottom 10 of the device to a predetermined position in the +Y direction in the grinding area by the Y-axis direction moving means 14, and the holding platform 30 will be positioned in the Y direction. The start position of axis direction feed. That is, the plate-shaped workpiece W held on the holding table 30 is positioned on the front side (the side in the −Y direction) where the distance between the lower surface 741 b of the grinding stone 741 and the holding surface 300 a of the holding table 30 is the smallest. Whetstone 741 is on the rear side.

Moreover, the grinding means 7 will be transmitted in the -Z direction by the moving means 5 in the Z-axis direction, and under the control of the moving means 5 in the Z-axis direction by the control means 9, the grinding means 7 will be positioned to become The grinding whetstone 741 in front of the lowermost end of the whetstone 741 cuts to a predetermined height position on the upper surface Wa of the plate-shaped workpiece W. As shown in FIG. That is, the lower surface 741b of the front grinding stone 741 is positioned lower than the upper surface Wa of the plate-shaped workpiece W held on the holding table 30 . In addition, the height position at which the grinding means 7 is positioned is the height position at which the lower surface 741b and the inner surface 741c of the front grinding stone 741 cut into the resin layer J and the electrode E by a predetermined amount. In addition, before the grinding process, the height position of the grinding means 7 in which the lower surface 741b of the grinding stone 741 in the front (-Y direction side) is in contact with the holding surface 300a of the holding table 30 is set up, The position of the lower surface 741b of the front grinding stone 741, which is positioned lower than the upper surface Wa of the plate-shaped workpiece W held on the holding table 30, is from the height position of the memory-built grinding means 7 to the plate-shaped workpiece W. The location on the finished thickness of .

(2) Grinding engineering The motor 72 shown in FIG. 1 rotates the rotating shaft 70 in the counterclockwise direction viewed from the +Z direction, for example, and the grinding wheel 74 rotates accordingly. As shown in FIG. 3 , the Y-axis direction moving means 14 moves the holding platform 30 that attracts and holds the plate-shaped workpiece W to the -Y direction at a predetermined feed speed, that is, the holding platform 30 moves to the -Y direction with respect to the grinding means 7. , moving to the direction from the rear (+Y direction side) of the grinding wheel 74 toward the front (−Y direction side). Then, the resin layer J of the plate-shaped workpiece W and the circular upper surface of the electrode E are ground with the lower surface 741b and the inner surface 741c of the grinding stone 741 rotating in front. In addition, an example of the ratio of the area of the resin layer J appearing on the upper surface Wa of the plate-shaped workpiece W to be ground to the total area of the circular upper surface of the full electrode E is, for example, the resin layer J: the circular upper surface of the full electrode E =20:80. In addition, the grinding whetstone 741 at the rear side of the rotation (+Y direction side) is the plate-shaped workpiece W that has not been ground.

Then, as shown in FIG. 4 , the holding table 30 is moved to a predetermined position in the -Y direction, and the entire upper surface Wa of the plate-shaped workpiece W is ground by the lower surface 741b and the inner surface 741c of the front grinding stone 741. , the grinding means 7 is pulled up to the +Z direction and separated from the plate-shaped workpiece W.

As mentioned above, the deep-cutting creep grinding method of the present invention is equipped with: the rotating shaft 70 is more inclined than the Z-axis direction with respect to the holding surface 300a of the holding platform 30, and the lower surface 741b of the grinding stone 741 is connected to the holding surface of the holding platform 30. The side where the distance of 300a is the smallest is set as the front of the grinding wheel 74, and the side where the distance between the lower surface 741b of the grinding stone 741 and the holding surface 300a of the holding platform 30 becomes the largest is set as the rear of the grinding wheel 74, using Z The axial direction moving means 5 positions the lower surface 741b of the grinding stone 741 at the front (-Y direction side) lower than the upper surface Wa of the plate-shaped workpiece W held on the holding table 30, and uses the Y axis direction moving means 14. The positioning process of positioning the plate-shaped workpiece W held on the holding table 30 on the rear side (+Y direction side) than the front grinding stone 741, and after the positioning process, use the Y-axis direction moving means 14 to make The holding table 30 moves toward the front (-Y direction) from the rear (+Y direction) of the grinding wheel 74 with respect to the grinding means 7, and grinds the plate shape with the lower surface 741b and the inner side surface 741c of the front grinding stone 741. In the grinding process of the workpiece W, the upper surface Wa of the ground surface of the plate-shaped workpiece W after grinding can be made into a beautiful ground surface with almost no unevenness or the like.

(Embodiment 2 of deep-cut creep grinding method) Hereinafter, each process related to the deep-cutting and creep-feed grinding of the plate-shaped workpiece W by the grinding device 1 will be described with reference to FIGS. 1 and 5 to 8 .

(1) Positioning engineering The positioning process is performed in the same manner as in Embodiment 1, and the plate-shaped workpiece W held on the holding table 30 is positioned at a distance from the holding surface 300a of the holding table 30 from the lower surface 741b of the grinding stone 741 shown in FIG. 5 . The grinding stone 741 that forms the smallest front side (the −Y direction side) is further to the rear side. In addition, the lower surface 741b of the grinding stone 741 at the front (the side in the −Y direction) is positioned lower than the upper surface Wa of the plate-shaped workpiece W held on the holding table 30 . In addition, the positioned height position of the grinding means 7 is that the lower surface 741b and inner side surface 741c of the front grinding stone 741 will cut into the resin layer J and the height position of the electrode E by a predetermined amount, so as to grind the plate-shaped The workpiece W is set at a height position Z0 (initial height position Z0 ) of a desired thickness (finished thickness). Furthermore, in the second embodiment, the height position of the memory grinding means 7 is also established in advance, and the front grinding stone is positioned lower than the upper surface Wa of the plate-shaped workpiece W held on the holding table 30. The position of the lower face 741b of 741 is the position from the height position of the grinding means 7 to the finished thickness of the plate-shaped workpiece W.

(2) Grinding engineering The motor 72 rotates the rotating shaft 70 counterclockwise as viewed from the +Z direction, and the grinding wheel 74 rotates accordingly. As shown in FIG. 6, the Y-axis direction moving means 14 moves the holding platform 30 that attracts and holds the plate-shaped workpiece W to the -Y direction, that is, the holding platform 30 moves to the grinding wheel 7 with respect to the grinding means 7. The rear (+Y direction side) of 74 faces the direction of the front (-Y direction side). Then, the lower surface 741b and the inner surface 741c of the rotating front grinding stone 741 are used to grind the resin layer J of the plate-shaped workpiece W and the circular upper surface of the electrode E.

(3) Measurement engineering In the grinding process, as shown in FIG. 6, at the same time as the above-mentioned deep-cut and slow-feed grinding process starts, the contact head 380 of the upper height measuring means 38 descends and contacts the outer side of the ring-shaped grinding stone 741 to start. After the plate-shaped workpiece W is ground, the height of the ground surface Wa is started to be measured. Then, the upper surface height measuring means 38 sequentially transmits the information about the measured height of the ground surface Wa immediately after the grinding of the plate-shaped workpiece W and the height of the ground surface Wa to be ground later per unit time. means of control9. The information transmitted to the control means 9 is sequentially stored in the memory unit 91 of the control means 9 .

For example, as shown in FIG. 6 , the height of the ground surface Wa of the plate-shaped workpiece W measured by the surface height measuring means 38 immediately after grinding is stored in the memory unit 91 as height Z1, for example. Further, the memory unit 91 memorizes the position of the front grinding stone 741 on the plate-shaped workpiece W in the Y-axis direction at the height Z1 as, for example, the position Y1. Furthermore, the grinding means 7 is located at the initial height position Z0 for setting the plate-shaped workpiece W to be ground to a desired thickness. (4) Correction works

In the grinding process, the grinding means 7 is moved in the Z-axis direction according to the measurement value measured by the upper surface height measuring means 38 in the measurement process, and the correction process of reducing the thickness difference of the plate-shaped workpiece W after grinding is performed. Specifically, as shown in FIG. 7, by moving the holding table 30 to the −Y direction, the upper surface Wa of the plate-shaped workpiece W is ground, and the calculation unit 92 shown in FIG. The height (measured value) of the upper surface Wa of the plate-shaped workpiece W sent from the upper surface height measuring means 38 to the control means 9 per unit time is calculated by subtracting the ground surface Wa of the plate-shaped workpiece W immediately after the grinding starts. The difference in height Z1. That is, for example, the height Z2 of the upper surface Wa of the plate-shaped workpiece W newly measured as shown in FIG. The difference L1 of the height Z1.

The calculated difference L1 is the difference in thickness of the plate-shaped workpiece W, and the wear amount from the front grinding stone 741 at the beginning of grinding. Once the calculation unit 92 calculates the difference L1, under the control of the control means 9, the moving means 5 in the Z-axis direction moves the grinding means 7 in the direction of the Z-axis to reduce the thickness of the plate-shaped workpiece W after grinding. Bad first correction. That is, the grinding means 7 at the initial height position Z0 approaches (descends) the plate-shaped workpiece W sucked and held on the holding surface 300a of the holding platform 30 by only a distance of the difference L1, and grinds the plate-like workpiece W. After this correction, the height of the upper surface Wa of the plate-shaped workpiece W to be ground becomes the height Z1 again, and the plate-shaped workpiece W to be ground becomes the desired thickness.

Grinding is further performed, and the height position Z3 of the upper surface Wa of the plate-shaped workpiece W newly measured by the upper surface height measuring means 38 shown in FIG. The calculation part 92 calculates the difference L2 of the height Z1 of the ground surface Wa after grinding. The calculated difference L2 is the difference in thickness of the plate-shaped workpiece W, and the wear amount after the above-mentioned first correction of the grinding stone 741 from the front. Then, under the control of the control means 9, the moving means 5 in the Z-axis direction will move the grinding means 7 in the Z-axis direction to perform the second correction of reducing the thickness difference of the plate-shaped workpiece W after grinding. . That is, the grinding means 7 approaches and grinds the plate-shaped workpiece W only by the distance of the difference L2, whereby the height position of the upper surface Wa of the plate-shaped workpiece W to be ground after the second correction will be changed. The height Z1 is reached again, and the plate-shaped workpiece W to be ground becomes a desired thickness.

In this way, in the grinding process, the height measurement of the upper surface Wa of the plate-shaped workpiece W of the upper surface height measurement means 38 arranged on the outer side of the annular grinding stone 741 and the grinding means 7 to Z corresponding to the measured value The correction of movement in the axial direction is repeated per unit time, while the holding table 30 moves to a predetermined position in the -Y direction, and the plate-shaped workpiece W is ground by the lower surface 741b and the inner surface 741c of the grinding stone 741 in front. After the upper surface Wa of W is fully formed, the grinding means 7 is pulled up to the +Z direction and separated from the plate-shaped workpiece W.

Here, problems related to the conventional deep-cut creep grinding method will be briefly described using FIGS. 11 to 13 . In the conventional deep-cut and creep-feed grinding method, the grinding means 7 will be transported in the -Z direction by moving the means 5 in the Z-axis direction, and the lower surface 741b of the grinding stone 741 at the front (-Y direction side) will be positioned at The predetermined amount is cut to the height position of the resin layer J and the electrode E of the plate-shaped workpiece W held on the holding table 30 . Then, the Y-axis direction moving means 14 moves the holding table 30 that attracts and holds the plate-shaped workpiece W to the +Y direction in the direction from the front to the rear of the grinding wheel 74 at a predetermined feed speed. Then, as shown in FIG. 12 , the resin layer J of the plate-shaped workpiece W and the circular upper surface of the electrode E are ground with the lower surface 741b and the outer surface 741d of the rotating front grinding stone 741 .

As shown in FIG. 13 , the holding table 30 is moved to a predetermined position in the -Y direction, and the entire upper surface Wa of the plate-shaped workpiece W is ground by the lower surface 741b and the outer surface 741d of the front grinding stone 741, and then ground. The cutting means 7 is pulled up in the +Z direction and separated from the plate-shaped workpiece W.

As shown in FIG. 13 , for example, if the conventional deep-cut creep grinding is performed on a long plate-shaped workpiece W, the thickness of the place where the grinding stone 741 begins to penetrate into the plate-shaped workpiece W will be reduced due to the abrasion of the grinding stone 741. There is a large difference in thickness from the thickness at which the grinding stone 741 separates from the plate-shaped workpiece W. In addition, irregularities and the like are generated on the surface Wa of the ground surface of the plate-shaped workpiece W after grinding. Moreover, when the workpiece is a plate-shaped workpiece W or the like provided with an electrode E made of copper, since the grinding stone 741 is a stone with a large hole ratio or size, the grinding of the plate-shaped workpiece W will The amount of abrasion for cutting also increases, and the difference in thickness becomes particularly large.

On the other hand, in the deep-cut and creep-feed grinding method according to the second embodiment of the present invention, as in the case of the first embodiment, the upper surface Wa of the ground surface of the plate-shaped workpiece W after grinding shown in FIG. It becomes a beautiful ground surface with almost no irregularities. Furthermore, the deep-cut and creep-feed grinding of the present invention is to measure the plate-shaped workpiece W immediately after the deep-cut and creep-feed grinding is started by using the upper surface height measuring means 38 arranged on the outer side of the annular grinding stone 741. The measurement process of the height of the upper surface Wa to be ground, and the correction process of moving the grinding means 7 in the Z-axis direction according to the measured value measured in the measurement process to reduce the thickness difference of the plate-shaped workpiece W after grinding, The difference in thickness of the plate-shaped workpiece W after grinding can be reduced as shown in FIG. 8 .

(Embodiment 3 of deep-cut creep grinding method) Hereinafter, each process related to the deep-cutting and creep-feed grinding of the plate-shaped workpiece W by the grinding device 1 will be described with reference to FIG. 1 and FIGS. 9 to 10 .

(1) Positioning engineering As shown in FIG. 9 , the Y-axis direction moving means 14 moves the holding platform 30 that attracts and holds the plate-shaped workpiece W from the loading and unloading area on the bottom 10 of the device to the grinding area to the +Y direction, and is held on the holding platform 30. The plate-shaped workpiece W is positioned behind the grinding stone 741 in front (on the −Y direction side) where the distance between the lower surface 741 b of the grinding stone 741 and the holding surface 300 a of the holding table 30 is the smallest.

Moreover, the grinding means 7 will be transported in the -Z direction by the moving means 5 in the Z-axis direction, and under the control of the moving means 5 in the Z-axis direction of the control means 9, the lower surface 741b of the grinding stone 741 that forms the front will be It is positioned lower than the upper surface Wa of the plate-shaped workpiece W held on the holding table 30 . At the same time, the lower surface 741b of the grinding stone 741 forming the rear (+Y direction side) is positioned lower than the upper surface Wa of the plate-shaped workpiece W held on the holding table 30 . The positioned height position of the grinding means 7 is, for example, the height position where the lower surface 741b of the grinding stone 741 at the rear and the lower surface 741b of the grinding stone 741 at the front will cut into the resin layer J and the electrode E by a predetermined amount, so as to be The height position Z4 of the plate-shaped workpiece W to be ground by the front grinding stone 741 has a desired thickness (finished thickness). Furthermore, in the third embodiment, the height position of the memory grinding means 7 is established in advance, and the front grinding stone is positioned lower than the upper surface Wa of the plate-shaped workpiece W held on the holding table 30. The position of the lower face 741b of 741 is the position from the height position of the grinding means 7 to the finished thickness of the plate-shaped workpiece W.

As shown in FIG. 10 , the Y-axis direction moving means 14 moves the holding table 30 that sucks and holds the plate-shaped workpiece W to the −Y direction. That is, the holding table 30 is moved in a direction from the rear (+Y direction side) of the grinding wheel 74 toward the front (−Y direction side) with respect to the grinding means 7 . Then, first, the resin layer J of the plate-shaped workpiece W and the circular upper surface of the electrode E are ground by the lower surface 741b and the outer surface 741d of the rotating rear grinding stone 741 . Then, the upper surface Wa of the plate-shaped workpiece W ground by the rotating rear grinding stone 741 is chased from the -Y direction toward the +Y direction, and the lower surface 741b and the inner surface 741c of the rotating front grinding stone 741 are drawn to the front surface Wa. During grinding, the plate-shaped workpiece W is formed into a desired thickness. Then, the holding table 30 is moved to a predetermined position in the -Y direction, and the entire upper surface Wa of the plate-shaped workpiece W is ground by the lower surface 741b and the inner surface 741c of the grinding stone 741 in front of the rotation, and then the grinding means 7 It will be pulled up to the +Z direction and separated from the plate-shaped workpiece W.

In the deep-cut and creep-feed grinding method according to Embodiment 3 of the present invention, in the positioning process, the lower surface 741b of the grinding stone 741 at the rear (+Y direction side) is positioned at a position higher than that held on the holding table 30. At the position where the upper surface Wa of the plate-shaped workpiece W is lower, the plate-shaped workpiece W is largely ground first with the outer surface 741d and the lower surface 741b of the rear grinding stone 741, and further, the inner surface 741c of the front grinding stone 741 is used to grind the plate-shaped workpiece W. and the lower surface 741b to grind the upper surface Wa of the plate-shaped workpiece W ground by the outer surface 741d and the lower surface 741b of the rear grinding stone 741, whereby the upper surface Wa of the plate-shaped workpiece W after grinding can be almost Beautiful surface to be ground with irregularities.

The deep-cut and creep-feed grinding method of the present invention is not limited to the above-mentioned Embodiments 1 to 3, and it is of course possible to implement various different embodiments within the scope of the technical idea. In addition, the components of the grinding apparatus 1 shown in the drawings are not limited thereto, and can be appropriately changed within the range in which the effects of the present invention can be exhibited. For example, in the deep-cut creep grinding method of the third embodiment, measurement process and correction process can also be performed.

W‧‧‧Plate Workpiece W1‧‧‧substrate W2‧‧‧chip E‧‧‧Electrode J‧‧‧resin layer 1‧‧‧Grinding device 10‧‧‧The bottom of the device 11‧‧‧Pillar 14‧‧‧Moving means in Y axis direction 140‧‧‧Ball screw 141‧‧‧A pair of guide rails 142‧‧‧motor 143‧‧‧movable plate 30‧‧‧maintain the platform 300‧‧‧Adsorption part 300a‧‧‧Retaining surface 301‧‧‧frame 34‧‧‧rotation means 39‧‧‧cover 39a‧‧‧Constrictor cover 38‧‧‧Measurement of upper height 380‧‧‧Contact head 381‧‧‧arm 5‧‧‧Z-axis direction movement means 50‧‧‧Ball screw 51‧‧‧A pair of guide rails 52‧‧‧motor 53‧‧‧lifting plate 7‧‧‧Grinding means 70‧‧‧rotation axis 71‧‧‧Chassis 72‧‧‧motor 73‧‧‧fixed stand 74‧‧‧Grinding wheel 740‧‧‧wheel abutment 741‧‧‧Grinding Whetstone 75‧‧‧Stent 9‧‧‧Control means 91‧‧‧memory department 92‧‧‧calculation department

FIG. 1 is a perspective view showing an example of a grinding device. Fig. 2 is a side view illustrating a state in which the lower surface of the front grinding stone is positioned lower than the upper surface of the plate-shaped workpiece, and the plate-shaped workpiece is positioned to the rear side of the front grinding stone by means of moving in the Y-axis direction . Fig. 3 illustrates that the holding platform is moved to the direction from the rear of the grinding wheel towards the front of the grinding means by using the moving means in the Y-axis direction, and the plate-shaped workpiece is started to be ground from the underside and inner side of the grinding stone in front side view of the state. Fig. 4 is a side view of a state in which the upper surface of a plate-shaped workpiece is completely ground by grinding the lower surface and the inner surface of the front grinding stone. Fig. 5 is a side view illustrating a state in which the lower surface of the front grinding stone is positioned lower than the upper surface of the plate-shaped workpiece, and the plate-shaped workpiece is positioned to the rear side of the front grinding stone by means of moving in the Y-axis direction picture. Fig. 6 illustrates that the holding platform is moved to the direction from the rear of the grinding wheel toward the front of the grinding means by using the moving means in the Y-axis direction, and the plate-shaped workpiece is started to be ground from the lower surface and the inner side of the grinding stone in front side view of the state. 7 is a side view illustrating the case of moving the grinding means in the Z-axis direction and performing correction to reduce the difference in thickness of the plate-shaped workpiece after grinding. 8 is a side view illustrating a state in which the upper surface of a plate-shaped workpiece is completely ground by grinding the lower surface and the inner surface of the front grinding stone. Figure 9 illustrates positioning the bottom of the front grinding stone lower than the upper surface of the plate-shaped workpiece, and positioning the lower surface of the rear grinding stone lower than the upper surface of the plate-shaped workpiece, and moving in the Y-axis direction Means, a side view of the state where the plate-shaped workpiece is positioned to the rear side of the front grinding stone. Fig. 10 is a side view illustrating a state in which the upper surface of a plate-shaped workpiece is ground with the lower surface and outer surface of the rear grinding stone, and the upper surface of the plate-shaped workpiece is ground with the lower surface and inner surface of the front grinding stone. picture. Fig. 11 illustrates that in the conventional deep-cutting and slow-feed grinding method, the lower surface of the front grinding stone is positioned lower than the upper surface of the plate-shaped workpiece, and the plate-shaped workpiece is positioned lower than the front surface of the plate-shaped workpiece by means of moving in the Y-axis direction. A side view of the state of the grinding whetstone on the front side. Fig. 12 illustrates that in the conventional deep-cut and creep-feed grinding method, the holding platform is moved to the direction from the front of the grinding wheel toward the rear for the grinding means, and the grinding is started on the lower surface and the outer surface of the grinding stone in front. A side view of the state of a chipped workpiece. 13 is a side view illustrating a state in which the upper surface of a plate-shaped workpiece is completely ground by grinding the lower surface and the outer surface of the front grinding stone in the conventional deep-cut and creep-feed grinding method.

5‧‧‧Z-axis direction movement means

7‧‧‧Grinding means

14‧‧‧Moving means in Y axis direction

30‧‧‧maintain the platform

70‧‧‧rotation axis

73‧‧‧fixed stand

74‧‧‧Grinding wheel

141‧‧‧A pair of guide rails

143‧‧‧movable plate

300a‧‧‧Retaining surface

740‧‧‧wheel abutment

741‧‧‧Grinding Whetstone

741b‧‧‧below

741c‧‧‧inner side

E‧‧‧Electrode

J‧‧‧resin layer

W‧‧‧Plate Workpiece

W1‧‧‧substrate

W2‧‧‧chip

Wa‧‧‧above

Wb‧‧‧below

Claims (2)

A deep-cut and creep-feed grinding method, which uses a grinding device to grind a plate-shaped workpiece with a grinding whetstone positioned at a lower position than the upper surface of the plate-shaped workpiece. The device includes: a holding platform having a holding surface for holding the plate-shaped workpiece; and a grinding means for attaching a grinding wheel ring-shaped with the grinding stone to a fixed table connected to the front end of the rotating shaft. The frame rotates the rotating shaft to grind the plate-shaped workpiece with the grinding stone; the Y-axis direction moving means moves the holding platform and the grinding means relatively in the Y direction parallel to the holding surface direction. axis direction; and Z-axis direction moving means, which makes the grinding means move in the Z-axis direction perpendicular to the Y-axis direction and perpendicular to the holding surface, characterized in that: the rotation axis is for the holding surface, It is more inclined than the Z-axis direction, and the side where the distance between the lower surface of the grinding stone and the holding surface is the smallest is defined as the front of the grinding wheel, and the distance between the lower surface of the grinding stone and the holding surface is the largest. The side is set to the rear of the grinding wheel, and a positioning process is provided, which uses the moving means in the Z-axis direction to position the lower surface of the front grinding stone to be closer than the upper surface of the plate-shaped workpiece held on the holding platform. low, and the lower side of the grinding stone at the rear is positioned at a lower position than the upper surface of the plate-shaped workpiece held on the holding platform, and the plate-shaped workpiece held on the holding platform is moved using the Y-axis direction movement means. Workpiece The grinding stone located on the rear side of the front; and the grinding process, which is after the positioning process, using the Y-axis direction moving means to move the holding platform from the grinding wheel to the grinding means The rear side faces the front direction, and after grinding the plate-shaped workpiece with the outer surface and the lower surface of the rear grinding stone, the plate-shaped workpiece is ground with the lower surface and the inner surface of the front grinding stone. For example, the deep-cut and creep-feed grinding method of item 1 of the scope of the patent application, wherein, it has: a measurement process, which is to measure the initial deep-cut and creep-feed grinding by means of measuring the upper surface height arranged on the outside of the aforementioned ring-shaped grinding stone The upper surface height of the plate-shaped workpiece after grinding; and the correction process, which is to move the aforementioned grinding means in the Z-axis direction according to the measured value measured in the measurement process, and reduce the thickness difference of the plate-shaped workpiece after grinding.