TW201544246A - Double-end surface grinding method and double-end surface grinder - Google Patents

Abstract

The present invention relates to a double-end surface grinding method and a double-end surface grinder, which can prevent a working piece from damage caused by a static pressure pad in delivering the work piece, while easily ensuring the support of the work piece at the side of the static pressure pad. In the double-end surface grinding method of the present invention, a carrier 7 is employed to rotate a thin plate like work piece W supported by the static pressure of a pair of static pressure pads 1 and 2, while grinding both surfaces of the work piece W by means of a pair of grinding stones 5 and 6. When the work piece W in the carrier 7 is being delivered, fluid is ejected from one side of the static pressure pad 2 to a side of the work piece W. At this moment, by means of a negative pressure induced by Bernoulli effect, the static pressure pad 2 at one side absorbs and holds the work piece W in a contactless manner.

Description

Two-face grinding method and two-face surface grinder

The invention relates to a two-face grinding method and a two-face surface grinding machine for performing two-side surface grinding on a workpiece.

In the horizontal two-end surface grinding machine, when both sides of the thin plate-shaped workpiece such as a silicon wafer are ground, the workpiece is statically supported by the pair of static pressure pads from both sides in the thickness direction. The workpiece is rotated, and both sides of the workpiece are ground to a predetermined thickness by a pair of grinding stones.

When a vacuum suction type loading/unloading means is used to carry in and out the workpiece with respect to the carrier, vacuum suction of the workpiece is performed by the static pressure pad on one side, and the workpiece is connected between the loading/unloading means and the static pressure pad on one side. Hand (Patent Document 1).

For example, in the case where the ground workpiece is discharged from the carrier to the outside of the machine, while the supply of the static pressure water from the two static pressure pads is stopped, the workpiece is vacuum-adsorbed by the static pressure pad on one side, and the workpiece is temporarily held. Fixed on one side of the static pressure pad. Next, a loading and unloading means is inserted between the carrier and the other static pressure pad, and the workpiece in the carrier is sandwiched from both sides by the carrying-out means and the one-side static pressure pad, and then the workpiece is pressed from the static pressure pad in this state. Delivery to the means of moving out.

[Previous Technical Literature] [Patent Literature]

[Patent Document 1] Japanese Patent Laid-Open Publication No. 2013-215813

In the conventional loading/unloading method, when the workpiece is vacuum-attached to one of the static pressure pads, the workpiece is strongly pressed against the one side of the static pressure pad due to the suction force, so that the suction side of the workpiece has a dent. , the problem of defects.

Even if dents or defects are generated on the workpiece, if it is generated when the workpiece is moved into the machine or before being carried in, the dents and defects can be removed in the grinding process, but if the workpiece is moved out after grinding Dent and defects directly lead to the occurrence of defective products in the workpiece.

Further, in the case where the workpiece is vacuum-adsorbed on the static pressure pad on one side, a device such as a vacuum line including a vacuum pump is required, which has a problem of increasing the equipment cost. Further, when the workpiece is vacuum-adsorbed, there is a risk that the vacuum line is mixed with the grinding water and the static pressure water for the static pressure support, and the pressure sensor or the vacuum pump of the vacuum line is damaged due to the grinding water or the static pressure water or Damage, etc., have the disadvantage of cost and time for maintenance and management.

As a method of preventing such dents and defects, it is conceivable that the vacuum suction force is weakened by the regulator, and the workpiece is adsorbed with a weak vacuum adsorption force. However, as long as the workpiece directly contacts the holding surface of the static pressure pad, even if the vacuum suction force is weakened, the dents and defects of the workpiece cannot be completely prevented.

Further, as another method of preventing dents and defects, it is conceivable to utilize the surface tension of water without using vacuum adsorption. However, when the workpiece is carried in, it is difficult to confirm the surface tension of the water, and it is difficult to confirm the suction of the workpiece by the static pressure pad. In order to determine whether the fitting of the notch portion of the workpiece and the engagement portion of the carrier is successful, it is necessary to additionally provide a vacuum. Type of sensor. Therefore, although vacuum adsorption is not employed, there is a problem that the vacuum line cannot be eliminated.

Further, since the workpiece cannot be sucked by the static pressure pad, for example, by setting a timer in advance, the timer sets the working time required for sucking the workpiece, and the working time is measured by the timer, and the end of the suction of the workpiece is confirmed from the time. time. However, in this case, there is a problem in that the confirmation of the workpiece suction requires sufficient time and the work efficiency is lowered, and the reliability is not confirmed because the workpiece adsorption end cannot be directly confirmed.

The present invention has been made in view of the existing problems, and an object thereof is to provide a two-face surface grinding method and a two-face surface grinder, which can prevent damage of a workpiece due to a static pressure pad during pick-up, and can be easily confirmed on the static pressure pad side. Workpiece retention while reducing equipment cost, management and maintenance costs.

The present invention relates to a two-face surface grinding method in which a thin plate-shaped workpiece supported by a pair of static pressure pads is rotated through a carrier, and the workpiece is ground by a pair of grinding stones. On both sides of the carrier, when the workpiece in the carrier is delivered, the static pressure pad from one side is ejected to the workpiece side, and the negative pressure generated by the Bernoulli effect is On the side of the static pressure pad on the side The non-contact approach attracts the workpiece.

There is also a case where the workpiece sucked by the loading means reaches the static pressure pad on the one side of the forward holding position, and the fluid is ejected from the static pressure pad on the one side to the workpiece side, and the static pressure on the side The pad side is attracted to hold the workpiece in a non-contact manner. Further, there is a case where the vacuum suction of the loading means is released immediately after the suction/holding of the workpiece on the static pressure pad side of the one side or the suction holding.

Alternatively, the other static pressure pad may be advanced to the forward holding position, and the workpiece is clamped from both sides by the two static pressure pads, and after the ejection of the fluid from the static pressure pad of the one side is released, the two statics are The pressure pad supplies a static pressure fluid and static pressure supports the workpiece.

After the grinding of the workpiece, the fluid may be ejected from the static pressure pad on the side immediately after the supply of the static pressure fluid to the static pressure pads is stopped or immediately after the supply is stopped, and the static pressure on the side may be The pad side is attracted to hold the workpiece in a non-contact manner.

Preferably, the static pressure fluid is supplied from the other static pressure pad substantially simultaneously with the suction of the workpiece by the static pressure pad on the one side, or immediately after the suction is held, while eliminating the influence of the surface tension of the static pressure fluid. The workpiece is pressed to the side of the static pressure pad on one side.

Preferably, the workpiece is clamped from both sides by the static pressure pad and the unloading means on the one side, and the side is released immediately after vacuum suction of the workpiece by the unloading means or vacuum adsorption. The suction of the static pressure pad is maintained, and the static pressure fluid is supplied from the static pressure pad on the one side to move the workpiece away from the static pressure pad on the one side. The fluid can also be compressed air.

The invention also relates to a two-head surface grinder having: a carrier that rotates a thin plate-shaped workpiece; a pair of static pressure pads that statically support the workpiece in the carrier; a pair of grinding stones, the pair of grinding stones The pressure pad is supported by static pressure to grind both sides of the rotating workpiece; and the loading/unloading means sucks the workpiece and carries it in and out with respect to the pair of static pressure pads, and the static movement on one side The pressure pad has an injection hole for discharging the fluid to the workpiece side, and the negative pressure generated by the Bernoulli effect at this time is sucked and held in a non-contact manner on the static pressure pad side of the one side. Workpiece.

The injection holes may be disposed at a plurality of positions in the circumferential direction including the vicinity of the engagement portion of the carrier that is engaged with the notch portion of the workpiece. There may also be a sensor that confirms the suction retention of the workpiece based on a change in the flow rate or pressure of the fluid ejected from the injection hole.

The static pressure pad on the one side may have a plurality of the injection holes arranged substantially equidistantly in the circumferential direction on the outer peripheral portion. Each of the static pressure pads may have a notch portion corresponding to the grinding stone, and the static pressure pad on the one side has a plurality of the injection holes arranged substantially equidistantly in the circumferential direction on the peripheral edge portion of the notch portion.

According to the present invention, it is advantageous in that the workpiece can be prevented from being damaged by the static pressure pad at the time of delivery, and the holding of the workpiece on the static pressure pad side can be easily confirmed, and the equipment cost, management, and maintenance can be reduced. cost.

1, 2‧‧‧ static pressure pad

3, 4‧‧ ‧ gap

5, 6‧‧‧ grinding grinding stone

7‧‧‧ Carrier

8‧‧‧Relocation means

9‧‧‧Removal means

10, 11‧‧‧ Static pressure support surface

12.13‧‧‧ recess

14, 15‧‧ ‧ convex

16, 17‧‧ ‧ discharge trough

18‧‧‧Spray hole

19‧‧‧ recess

20‧‧‧Clock Department

21, 22‧‧‧ opening and closing control means

23‧‧‧ Static pressure water supply source

24‧‧‧Opening and closing control means

25‧‧‧ Fluid supply source

26‧‧‧Flow sensor

27‧‧‧ Pressure Sensor

36‧‧‧ movable frame

37, 38‧‧‧ adsorption cup

W‧‧‧Workpiece

1 is a schematic cross-sectional view showing a horizontal two-end surface grinder according to a first embodiment of the present invention; FIG. 2 is a side view showing a horizontal two-end surface grinder according to a first embodiment of the present invention; and FIG. FIG. 4 is a cross-sectional view showing a shape of an injection hole of a horizontal two-end surface grinder according to a first embodiment of the present invention; FIG. 5 is a view showing the present invention; FIG. 6 is an explanatory view showing the operation of the horizontal double-end surface grinder according to the first embodiment of the present invention; FIG. 7 is a view showing the operation of the transverse-type two-head surface grinder according to the first embodiment of the present invention; FIG. 8 is a view showing the operation of the horizontal double-end surface grinder according to the first embodiment of the present invention, and FIG. 9 is a view showing the operation of the horizontal double-head surface grinder according to the first embodiment of the present invention. FIG. FIG. 10 is an operation explanatory view showing a horizontal two-end surface grinder according to a first embodiment of the present invention; and FIG. 11 is a horizontal cross-head showing a first embodiment of the present invention. Surface grinding operation explanatory view; FIG. 12 is a lateral aspect of the first embodiment of the present invention two surface grinder to explain the operation; FIG. 13 is a lateral aspect of the first embodiment of the present invention, two plane Fig. 14 is an operation explanatory view showing a horizontal two-end surface grinder according to a first embodiment of the present invention; and Fig. 15 is an operation explanatory view showing a horizontal two-end surface grinder according to the first embodiment of the present invention; Fig. 16 is an operation explanatory view showing a horizontal two-end surface grinder according to a first embodiment of the present invention; and Fig. 17 is an operation explanatory view showing a horizontal two-end surface grinder according to a first embodiment of the present invention; FIG. 19 is a schematic side view showing a static pressure pad according to a second embodiment of the present invention; and FIG. 20 is a view showing a third embodiment of the present invention. Schematic illustration of a pressure pad.

[Formation of the Invention]

Embodiments of the present invention will be described in detail below with reference to the drawings. Figures 1 and 2 illustrate a horizontal two-face surface grinder employing the present invention.

As shown in FIG. 1 and FIG. 2, the horizontal two-stage surface grinder has a pair of right and left static pressure pads 1, 2, and the pair of right and left static pressure pads 1, 2 are disposed to face each other on the right and left sides, and static pressure support 矽a thin plate-shaped workpiece W such as a wafer; a pair of right and left grinding stones 5 and 6, and the pair of left and right grinding stones 5 and 6 correspond to the notch portions 3 and 4 on the lower side of each of the static pressure pads 1 and 2 , which is configured to be freely rotatable according to the axis around the left and right direction, and is ground by the static pressure pad 1 2, the left and right side faces of the workpiece W held; the carrier 7 which rotates the workpiece W supported by the static pressure pads 1 and 2 around the center; the loading/unloading means 8, 9 and the loading/unloading means 8 and 9 The workpiece W is carried in and out of the carrier 7 between the static pressure pads 1 and 2.

The static pressure pads 1 and 2 are freely moved in the left-right direction between the forward holding position X1 (grinding position) in the vicinity of the workpiece W and the retracted position X2 retreating from the workpiece W. Further, each of the static pressure pads 1 and 2 is statically pressurized (hereinafter referred to as static pressure water) such as static pressure water supplied from the static pressure support surfaces 10 and 11 facing the workpiece W at the forward holding position X1. The workpiece W is supported by the pressure, and the static pressure pad 2 on one side sprays a fluid such as compressed air (hereinafter referred to as compressed air) substantially perpendicularly toward the workpiece W side, and uses the negative pressure generated by the Bernoulli effect at this time. The non-contact manner attracts the workpiece W.

Further, in the following description, for the sake of simplicity, the static pressure pad 2 on one side is set as the right static pressure pad, and the static pressure pad 1 on the other side is set as the left static pressure pad on the premise of the horizontal two-end surface grinder. For the sake of explanation, the one side and the other side can also be swapped left and right.

In the static pressure supporting faces 10, 11 of the static pressure pads 1, 2, as shown in FIG. 3, a plurality of pockets 12, 13 for supplying hydrostatic water are provided in a dispersed manner; and the respective recesses 12, 13 are surrounded. Lands 14, 15; discharge grooves 16, 17 which discharge the static pressure water passing through the projections 14, 15 to the outside.

Further, in Fig. 3, the area of the static pressure supporting portion formed by the plurality of concave portions 12, 13 and the convex portions 14, 15 is large with respect to the discharge grooves 16, 17, but may be reversed The area of the discharge grooves 16, 17 is large in the plurality of static pressure support portions.

In the right static pressure pad 2 of the pair of static pressure pads 1, 2, as shown in FIGS. 1 to 3, a plurality of injection holes 18 are provided. The injection hole 18 has a function of injecting a predetermined pressure of compressed air substantially perpendicularly to the workpiece W side, and a negative effect caused by the Bernoulli effect when the compressed air flows between the workpiece W and the right static pressure pad 2 Pressing, the workpiece W is attracted and held in a non-contact manner on the right static pressure pad 2 side.

The injection hole 18 is formed to be perpendicular to the static pressure support surface 11 which is the top surface of the convex portion 15, and a plurality of injection holes 18 are provided in the circumferential direction of the outer peripheral portion of the right static pressure pad 2, for example, substantially equidistantly Configure 6. As shown in FIGS. 2 and 3, at least one of the six injection holes 18a is a card of the carrier 7 engaged with the notch portion 19 of the workpiece W when the carrier 7 is stopped at the reference stop position. The vicinity of the joint portion 20 is disposed correspondingly.

As shown in Fig. 4 (a), the shape and the structure of the respective injection holes 18 are substantially cylindrical in shape, and as shown in Fig. 4 (b), it is conceivable to provide a constricted portion 18c or the like on the opening end side. .

The injection hole 18 of Fig. 4(a) can discharge compressed air substantially perpendicularly to the workpiece W, and the flow of the compressed air after the injection is simple, and the negative pressure due to the Bernoulli effect can be effectively generated. However, depending on the pressure and flow rate of the compressed air, other shapes may be employed as shown in Fig. 4(b).

In addition, the number of the injection holes 18 necessary for the suction and holding of the workpiece W may be appropriately determined in consideration of the size of the workpiece W, etc., but it is preferable to arrange at least three substantially equidistantly. In addition, the spacing between the injection holes 18 may be slightly different. The diameter of the injection hole 18 is preferably It is about 1 to 5 mm, but as long as it can attract and hold the workpiece W in a non-contact state, the diameter can be larger or smaller than 1 to 5 mm.

The recessed portions 12 and 13 of the static pressure pads 1 and 2 are connected to a static pressure water supply source (static fluid supply source) 23 so as to open and close the opening and closing control means 21 and 22 such as an opening and closing valve. Each of the injection holes 18 is connected to a compressed air supply source (fluid supply source) 25 such as a pressure pump such that an opening/closing control means 24 such as an opening/closing valve is interposed, and between the injection hole 18 and the opening and closing control means 24 is provided. Flow sensor 26 or pressure sensor 27.

The grinding stones 5 and 6 are cup-shaped or the like, and are provided at the front end of the grindstone shaft (not shown) in the left-right direction, and move in the left-right direction between the forward end Y1 and the retreating end Y2, and advance on the Y1 side. Start grinding the workpiece W.

As shown in FIG. 2, the carrier 7 includes a carrier plate 30 having an inner circumference formed with a substantially concentric carrier hole 29 and having a thin plate shape thinner than the workpiece W; a carrier ring 31, the carrier ring 31 The outer peripheral portion of the carrier plate 30 is held. The carrier 7 is held in such a manner as to be freely rotatable around the center of the workpiece W by a plurality of support rollers 28 in the circumferential direction. The workpiece W is detachably attachable to the carrier hole 29. An engaging portion 20 is provided in the carrier plate 30, and the engaging portion 20 protrudes into the carrier hole 29.

The carrier ring 31 is substantially concentric with the carrier hole 29, and the drive gear 32 is engaged with the inner peripheral side of the carrier ring 31. The drive gear 32 is driven by a drive source outside the drawing by a drive shaft 34 that is inserted through the through hole 33 of the right static pressure pad 2.

As shown in FIG. 1, the loading/unloading means 8 and 9 have a movable frame 36 which is provided to be movable in the left-right direction and the front-rear direction, and the loading means 8 and the carrying-out means 9, the loading means 8 and the carrying-out means 9 can move up and down respectively on the movable frame 36, and the loading means 8 and moving The means 9 sucks the workpiece W by the suction cups 37, 38, and carries in and out the workpiece W with respect to the carrier 7.

The loading/unloading means 8 is floatably supported in the vertical direction and the front-rear direction of the movable frame 36, and is guided by the guiding means 40 such as a roller when approaching the carrier 7, and the workpiece W adsorbed by the suction cup 37 and the carrier hole 29 of the carrier 7 are provided. Floating roughly in unison.

Further, the suction cups 37 and 38 have an appropriate degree of elasticity, and do not damage the workpiece W during vacuum suction, and one or a plurality of (for example, three) portions are provided corresponding to the substantially central portion of the workpiece. The carry-in means 8 and the carry-out means 9 are formed so that the carry-out means 9 rises when the workpiece W is carried in by the carry-in means 8, and when the workpiece W is carried out by the carry-out means 9, the carry-in means 8 rises, etc., and the retraction does not hinder the other party's work. Retreat position. The loading means 8 may be provided so as to be lifted and lowered non-floatingly with respect to the movable frame 36.

Next, the grinding cycle in the two-plane grinding method in which both side faces of the workpiece W are ground by the lateral two-end surface grinder will be described with reference to the explanatory drawings of FIG. 5 and the operation explanatory views of FIGS. 6 to 17 . The grinding cycle includes a step of loading the workpiece W before the grinding, a grinding step of grinding the workpiece W, and a step of carrying out the workpiece W after the grinding.

When the workpiece W is carried in and out of the machine, if the workpiece W is inclined with respect to the carrier 7, the workpiece W may be loosened from the carrier 7. Therefore, when the workpiece W is delivered, compressed air is ejected from the respective injection holes 18 of the right static pressure pad 2 toward the workpiece W side, and the negative pressure generated by the Bernoulli effect at this time is used in a non-contact manner. The pressure pad 2 side sucks and holds the workpiece W, thereby preventing the workpiece W from coming off the carrier 7.

That is, as shown in Fig. 5, if compressed air is supplied from the injection hole 18 substantially perpendicularly to the workpiece W in the direction of the arrow a, the compressed air passes through the minute gap between the right static pressure pad 2 and the workpiece W, while being outwardly side. It flows almost in the circumferential direction and flows in the direction of arrow b.

If the flow velocity V2 of the compressed air flowing to the outside through the gap between the right static pressure pad 2 and the workpiece W is increased with respect to the flow velocity V1 of the compressed air in the injection hole 18 at this time, the injection hole is appropriately set. The aperture of 18, the gap between the right static pressure pad 2 and the workpiece W, and the pressure (flow) of the compressed air are surrounded by the Bernoulli effect of the compressed air between the right static pressure pad 2 and the workpiece W. The negative pressure generating portion c of the broken line region of the injection hole 18 generates a negative pressure, and the workpiece W can be attracted to the right static pressure pad 2 side by the negative pressure of the negative pressure generating portion c.

Further, since the flow of the compressed air corresponding to the gap amount is between the right static pressure pad 2 and the workpiece W, the workpiece W is in a non-contact state with respect to the right static pressure pad 2.

Therefore, by holding and holding the workpiece W in a non-contact manner, the workpiece W can be fixed to the right static pressure pad 2, and the workpiece W can be prevented from falling off while preventing the dents and other damage of the workpiece W caused by the suction and holding. .

6 shows a state before the workpiece W is carried in. The left and right grinding stones 5 and 6 are located at the retreating end Y2, the left static pressure pad 1 is located at the retracted position X2, and the right static pressure pad 2 is located at the advancing holding position X1 in the vicinity of the carrier 7.

Therefore, when the workpiece W before grinding is carried into the machine and the carrier 7 is mounted between the static pressure pads 1 and 2, the workpiece W is first vacuum-adsorbed by the suction cup 37 of the loading device 8. Next, the loading means 8 is entered into the carrier Between 7 and the left static pressure pad 1, as shown in Fig. 7, the workpiece W is placed on the axis of the carrier hole 29 of the carrier 7. Then, the loading means 8 is moved to the side of the carrier 7, and as shown in Fig. 8, the workpiece W is inserted into the carrier hole 29 of the carrier 7.

At this time, as shown in FIG. 2, the engaging portion 20 is positioned at the reference stop position where it should be located, and the workpiece W is adsorbed in a state in which the recess 19 corresponds to the card of the carrier 7. The joint 20 is positioned. Therefore, by moving the loading means 8 to the carrier 7 side, as shown in FIG. 2, the concave portion 19 of the workpiece W can be easily engaged with the engaging portion 20 of the carrier 7.

If the workpiece W is inserted into the carrier hole 29, the workpiece W is brought into contact with the right static pressure pad 2 located at the forward holding position X1, as shown in Fig. 8, between the right static pressure pad 2 and the loading means 8, from both sides The workpiece W located in the carrier 7 is held. Further, as shown in Fig. 5, compressed air is then ejected from the respective injection holes 18 of the right static pressure pad 2 toward the workpiece W side, by the Bernoulli effect of the compressed air flowing between the workpiece W and the right static pressure pad 2. The generated negative pressure attracts and holds the workpiece W in a non-contact manner on the right static pressure pad 2 side.

Further, in the case where the workpiece W is held in a non-contact manner by the right static pressure pad 2, the gap between the right static pressure pad 2 and the workpiece W is extremely small. Therefore, in order to facilitate the drawing, the state in which the right static pressure pad 2 and the workpiece W are in contact with each other is described in FIG. 8, and the "suction holding" and the "non-contact" are marked, indicating that the workpiece W is attracted and held in a non-contact state. status. The same is true below.

As shown in FIG. 3, each of the injection holes 18 is provided at substantially equal intervals in the outer peripheral portion of the right static pressure pad 2, for example, six, by ejecting from the respective injection holes 18 and flowing through the workpiece W and the right. Between the static pressure pads 2 The Bernoulli effect of the compressed air of the gap attracts substantially the entire circumference of the outer peripheral portion of the workpiece W to the right static pressure pad 2 side, whereby the outer peripheral side of the workpiece W can be fixed to the right static pressure pad 2.

Further, if the right static pressure pad 2 sucks and holds the workpiece W, the pressure of the compressed air injected from the injection hole 18 rises, and the flow rate decreases, whereby the flow rate and pressure can be transmitted, and the flow rate sensor 26 or the pressure sensing can be utilized. The device 27 easily confirms the suction holding state of the workpiece W.

When the workpiece W is inserted into the carrier 7, it is necessary to require the concave portion 19 of the workpiece W adsorbed to the loading device 8 to be fitted to the engaging portion 20 of the carrier 7, and the insertion of the concave portion 19 is the most difficult, and insertion failure is likely to occur. However, in the vicinity of the recess 19, since there is an injection hole 18a connected to the flow sensor 26 or the pressure sensor 27, the insertion state of the recess 19 can be confirmed directly through the flow sensor 26 or the pressure sensor 27. .

That is, when the concave portion 19 of the workpiece W and the engaging portion 20 of the carrier 7 are displaced, and the workpiece W contacts the upper portion of the engaging portion 20, a gap having a wide thickness of the carrier 7 is generated between the workpiece W and the right static pressure pad 2, In this portion, there is a state in which there is no workpiece W. Therefore, the injection hole 18a injects compressed air without resistance, and it is possible to easily confirm whether or not the fitting of the recess 19 is successful by the flow sensor 26 or the pressure sensor 27.

When the concave portion 19 contacts the engaging portion 20, the flow sensor 24 or the pressure sensor 27 cannot confirm the suction holding of the workpiece W, and the insertion operation is continued every time the carrier 7 is rotated at a constant angle. At this time, since the workpiece W is in a state of being vacuum-adsorbed on the unloading means 9 side, if the carrier 7 only rotates the amount of displacement of the recess 19 and the engaging portion 20, the recess 19 can be aligned with the engaging portion 20, and the workpiece W can be used. Embedded in the carrier 7.

If the workpiece W is fitted into the carrier 7, the entire workpiece W is sucked and held by the right static pressure pad 2 in a non-contact manner, and the output of the flow sensor 26 and the pressure sensor 27 is changed, so that the workpiece can be confirmed. The attraction of W remains.

In addition, even if the flow sensor 24 or the pressure sensor 27 cannot confirm the suction and holding of the workpiece W even if the carrier 7 is rotated, there is a cause that the concave portion 19 such as the damage on the workpiece W side and the engagement portion 20 are misaligned. Therefore, the automatic cycle is stopped and the operator is notified of the occurrence of an abnormality.

When the workpiece W is sucked and held by the right static pressure pad 2, the vacuum suction of the workpiece W by the loading means 8 is released after confirming the suction holding or after the suction holding is confirmed, as shown in Fig. 9, the loading means 8 is withdrawn. Go outside the machine.

When the workpiece W is carried in before the grinding, the workpiece W is held by the suction cup 37 and the right static pressure pad 2 of the loading device 8, and the suction is maintained in the non-contact state of the right static pressure pad 2, By the delivery from the loading means 8 to the right static pressure pad 2, the workpiece W does not tilt and fall off in the carrier 7. Further, even if the loading means 8 is withdrawn to the outside of the machine, the workpiece W does not fall off from the right static pressure pad 2. Further, although the workpiece W is adsorbed and held on the right static pressure pad 2 side, damage of the workpiece W due to the right static pressure pad 2 can be prevented.

As shown in FIG. 10, once the loading means 8 is withdrawn outside the machine, the left static pressure pad 1 is advanced toward the forward holding position X1, and the workpiece W is held from both sides by a pair of static pressure pads 1, 2, and then stopped. The compressed air ejected from the injection holes 18 of the right static pressure pad 2 releases the suction and holding. In this state, the workpiece W in the carrier 7 is shown by a pair of static pressure pads 1, 2 as shown in FIG. Since the state is clamped from both sides, there is no possibility that the carrier 7 is inclined and falls off from the carrier 7.

As shown in Fig. 11, after the workpiece W is held by the pair of static pressure pads 1, 2, static pressure water is supplied from the static pressure pads 1 and 2 to the workpiece W side, and static pressure water is supported from both sides by static pressure water. Workpiece W. Further, while the workpiece W in the static pressure supporting state is integrally rotated with the carrier 7, as shown in Fig. 12, the pair of grinding stones 5, 6 are sequentially ground and advanced from the grinding position to the advanced end Y1 side. Each of the grinding stones 5, 6 grinds both sides of the workpiece W.

Once the grinding of the workpiece W is completed, as shown in Fig. 13, the left and right grinding stones 5, 6 are retracted to the retreating end Y2, and then the rotation of the carrier 7 is stopped. At this time, the carrier 7 is stopped at the reference stop position. This is to facilitate the insertion of the next workpiece W with respect to the carrier 7. Further, when the carrier 7 is stopped at the reference stop position, the supply of static pressure water from the two static pressure pads 1 and 2 is stopped, and the static pressure support of the workpiece W is released. At this time, water exists between the workpiece W and the static pressure pads 1 and 2 on both sides, and the workpiece W is in a state of being attached to the static pressure pads 1 and 2 on both sides due to the surface tension of the water.

At the same time as stopping the supply of the static pressure water from each of the static pressure pads 1, 2 or immediately after the supply is stopped, the compressed air is ejected from the injection holes 18 of the right static pressure pad 2 toward the workpiece W side, by which Bernoulli The negative pressure due to the effect, as shown in Fig. 14, attracts the workpiece W between the two static pressure pads 1, 2 in a non-contact manner on the right static pressure pad 2 side.

Therefore, since the workpiece W is in a fixed state on the right static pressure pad 2, even after the left static pressure pad 1 is retracted to the retracted position X2, the workpiece W after grinding in the carrier 7 does not tilt and fall off. In addition, although the workpiece W is fixed to the right static pressure pad 2, the workpiece W is sucked by compressed air. The lead is held on the right static pressure pad 2 side, and since the workpiece W is in a non-contact state on the right static pressure pad 2, damage of the workpiece W can be prevented.

Once the workpiece W is sucked and held on the right static pressure pad 2 side, the flow rate sensor 26 or the pressure sensor 27 can confirm the suction and holding of the workpiece W by the right static pressure pad 2 by the change in the flow rate or pressure of the compressed air.

Further, immediately after the suction holding of the workpiece W on the right static pressure pad 2 side or after the suction holding, the static pressure water is supplied from the left static pressure pad 1 to the workpiece W side as shown in FIG. 14 . By the supply of the hydrostatic water, the surface tension of the water such as static pressure water, grinding water or the like between the static pressure pad 1 and the left static pressure pad 1 does not affect the workpiece W, and the workpiece W is pushed to the right static pressure pad 2 Side, assisting the adsorption support.

Therefore, the separation of the workpiece W of the left static pressure pad 1 is easy, and the workpiece W can be surely attracted to the right static pressure pad 2 side by the negative pressure generated by the Bernoulli effect when the compressed air is injected. Therefore, the workpiece W after the grinding can be quickly attracted by the right static pressure pad 2, so that the grinding cycle can be shortened. In addition, since static water is used, it is not necessary to use a dedicated machine for releasing the surface tension.

After the workpiece W is sucked and held by the right static pressure pad 2, the left static pressure pad 1 is retracted from the forward holding position X1 to the retracted position X2 as shown by the double-dot chain line of FIG. Even when the left static pressure pad 1 is retracted, static pressure water is supplied from the left static pressure pad 1, whereby the surface tension of the water between the left static pressure pad 1 is transmitted, and the workpiece W is not detached from the right static pressure pad 2. The suction holding of the workpiece W by the right static pressure pad 2 can be surely maintained. Further, when the left static pressure pad 1 is retracted to ignore the influence of the surface tension, the supply of the static pressure water from the left static pressure pad 1 is stopped.

Thereafter, as shown in FIG. 15, if the left static pressure pad 1 is retracted toward the retreat position X2, the unloading means 9 is inserted between the carrier 7 and the left static pressure pad 1. Further, the unloading means 9 is moved to the side of the workpiece W, and as shown in Fig. 16, the workpiece W that is in a suction-holding state on the right static pressure pad 2 side is in contact with the suction cup 38 of the unloading means 9, and is carried out by the suction-out means After the means 9 and the right static pressure pad 2 hold the workpiece W from both sides, the workpiece W from the right static pressure pad 2 to the carry-out means 9 is transferred.

When the suction cup 38 of the unloading means 9 is brought into contact with each other, the workpiece W in the non-contact state with respect to the right static pressure pad 2 does not directly contact the right static pressure pad 2 at the time of contact with the suction cup 38 by impact, pressure, or the like. The movement of the unloading means 9 is stopped to perform positioning.

When the workpiece W is delivered, as shown in FIG. 17, the compressed air from the injection hole 18 of the right static pressure pad 2 is stopped, and the suction holding of the workpiece W is released. Then, the workpiece W is vacuum-adsorbed by the suction cup 38 of the unloading means 9 immediately after the suction holding is released or the suction holding is released. Thereby, the workpiece W can be easily and surely transferred between the right static pressure pad 2 and the carry-out means 9.

Further, immediately after releasing the suction holding of the right static pressure pad 2 or releasing the suction holding, immediately as shown in FIG. 18, static pressure water is supplied from the right static pressure pad 2 to the workpiece W, and the unloading means 9 is leftward. The static pressure pad 1 is moved, and the workpiece W is taken out from the carrier 7, and is carried out outside the machine.

In this manner, the static pressure water is supplied from the right static pressure pad 2 to the workpiece W side, and the workpiece W is taken out from the carrier 7, so that the surface tension between the right static pressure pad 2 and the workpiece W is not affected, and the surface can be easily removed. The workpiece W is separated from the right static pressure pad 2. Therefore, even if the workpiece W after grinding is thin, The time of the grinding cycle is shortened while reliably preventing the damage.

Further, the supply of the static pressure water from the right static pressure pad 2 continues until the surface tension between the workpiece W and the right static pressure pad 2 has no effect, and thereafter the supply is stopped.

When the unloading of the workpiece W after the grinding is completed, the same operation is sequentially repeated, and the workpieces W are sequentially ground.

In this manner, the negative pressure generated by the Bernoulli effect when the compressed air is ejected from the injection hole 18 of the right static pressure pad 2 toward the workpiece W side is in a non-contact state in which the slit is opened between the right static pressure pad 2, By sucking and holding the workpiece W on the right static pressure pad 2 side, it is possible to reliably prevent generation of other damage such as dents, adsorption marks, and defects of the workpiece W.

Further, since the compressed air is injected from the injection hole 18 of the right static pressure pad 2 to suck and hold the workpiece W, it is possible to prevent the grinding water and the static pressure water from being mixed into the flow rate sensor 26, the pressure sensor 27, and the like from the injection hole 18. There is no need to worry about the breakage of the flow sensor 26 and the pressure sensor 27 caused by the above mixing. Further, since a vacuum line including a vacuum pump is not required, it is possible to reduce the maintenance cost of the equipment and the like while reducing the equipment cost.

Further, the compressed air is injected from the injection hole 18 of the right static pressure pad 2 to suck and hold the workpiece W, and the flow rate sensor 26 and the pressure sensor 27 detect the flow rate and pressure change of the compressed air, so that the workpiece W can be easily grasped. Whether or not it is attracted and held, the workpiece W can be reliably delivered.

When the workpiece W is inserted into the carrier 7, the concave portion 19 of the workpiece W and the engaging portion 20 of the carrier 7 interfere with each other, and the workpiece W cannot be inserted into the carrier 7, the carrier 7 is rotated, but the concave portion 19 of the workpiece W at this time and Carrier 7 The engaging portion 20 comes into contact and rotates. However, in the case where the right static pressure pad 2 is sucked to hold the workpiece W in a non-contact state, since there is a gap between the right static pressure pad 2 and the workpiece W, the vacuum of the workpiece W with the existing right static pressure pad 2 In comparison with the adsorption phase, the contact force between the concave portion 19 of the workpiece W and the engaging portion 20 of the carrier 7 can be reduced, the impact and friction of the concave portion 19 can be reduced, and the life of the concave portion 19 can be improved.

Fig. 19 shows a second embodiment of the present invention. In this embodiment, a plurality of injection holes 18, for example, three injection holes 18, are disposed on the periphery of the notch portion 4 of the right static pressure pad 2 for grinding the grindstone 6, substantially equidistantly. The portion of the outer peripheral portion of the static pressure pad 2 that is away from the notch portion 4 is not provided with the injection hole 18.

In this case, the workpiece W may be sucked and held in a non-contact state on the right static pressure pad 2 side by jetting compressed air of a predetermined pressure from the injection hole 18. Therefore, the position of the injection hole 18 is not limited to the outer peripheral portion of the right static pressure pad 2, and may be disposed at another position such as the peripheral portion of the notch portion 4 for grinding the grindstone 6. Of course, the injection holes 18 may be simultaneously provided at the outer peripheral portion of the right static pressure pad 2 and the peripheral portion of the notch portion 4.

In this case as well, in the same manner as in the first embodiment, it is preferable to provide the injection hole 18a in the vicinity of the engagement portion 20.

Fig. 20 shows a third embodiment of the present invention. In the embodiment, when the workpiece W before the grinding is carried in, as in the first embodiment, the workpiece W is fixed to the right static pressure pad 2 by the suction holding by the injection of the compressed air, and the grinding is performed. When the subsequent workpiece W is carried out, the workpiece W is fixed to the right static pressure pad 2 by the surface tension of water such as static pressure water or grinding water.

That is, when the workpiece W before the grinding is carried in, the first embodiment In the same manner, compressed air is ejected from the injection hole 18 of the right static pressure pad 2 toward the workpiece W, and the negative pressure generated by the Bernoulli effect at this time attracts and holds the workpiece W in the non-contact state on the right static pressure pad 2.

After the grinding of the workpiece W, the right static pressure pad 2 and the workpiece W are in a state of being wetted by the static pressure water and the grinding water. Therefore, when the workpiece W is carried out, if the hydrostatic water or the grinding water is stopped, the workpiece W can be fixed to the right static pressure pad 2 by the surface tension of the water as shown in FIG. W is fixed on the right static pressure pad 2. After the workpiece W is vacuum-adsorbed by the unloading means 9, the static pressure water is supplied from the right static pressure pad 2 to the workpiece W side, and the workpiece W is separated from the right static pressure pad 2, as in the case of the first embodiment. Further, when the left static pressure pad 1 is moved back to the retracted position X2, the static pressure water is supplied from the left static pressure pad 1.

According to this, the suction holding of the workpiece W by the injection of the compressed air is used only when it is carried in, and it is easy to control. Further, by stopping the supply of the hydrostatic water and the grinding water, the workpiece W can be immediately fixed to the right static pressure pad 2, and the cycle time for the surface grinding of both sides of the workpiece W can be shortened.

The embodiments of the present invention have been described in detail above, but the present invention is not limited to the embodiments, and various modifications may be made without departing from the spirit and scope of the invention. For example, a horizontal two-end surface grinder is exemplified in this embodiment, but it can also be implemented in a vertical two-end surface grinder. Further, the workpiece W may be other than a silicon wafer or the like.

Further, in the embodiment, the case where the injection hole 18 is provided in the right static pressure pad 2 of the pair of static pressure pads 1 and 2, and the workpiece W is adsorbed on the right static pressure pad 2 side is shown, but An injection hole 18 is disposed on the left static pressure pad 1 And the workpiece W is adsorbed on the left static pressure pad 1 side.

When the workpiece W sucked by the loading means 8 is inserted into the carrier 7, after the loading means 8 and the right static pressure pad 2 are nipped, the loading means 8 can be released while the right static pressure pad 2 adsorbs the workpiece W. The adsorption of the workpiece W may release the adsorption of the workpiece W by the loading means 8 immediately after the right static pressure pad 2 adsorbs the workpiece W.

Further, when the fluid is supplied from the left static pressure pad 1 and the surface tension of the left static pressure pad 1 and the workpiece W is released, after the vacuum suction of the workpiece W by the unloading means 9, the fluid is supplied from the right static pressure pad 2, and the workpiece W In the case of leaving the right static pressure pad 2, if a static pressure pad fluid such as static pressure water of the fluid is used, it is not necessary to separately provide a fluid supply device, and the structure can be simplified, but it is also possible to supply static pressure water or the like. A special fluid other than a hydrostatic fluid.

After the workpiece W in the carrier 7 is nipped by the unloading means 9 and the right static pressure pad 2, the suction of the workpiece W by the static pressure pad 2 can be released while the loading means 9 adsorbs the workpiece W, from the right static pressure pad 2 When the static pressure water is supplied, the suction of the workpiece W by the static pressure pad 2 may be released immediately after the suction means 9 adsorbs the workpiece W, and the static pressure water may be supplied from the right static pressure pad 2.

When the static pressure water is supplied to the right static pressure pad 2 when the workpiece W is carried out, the supply system of the static pressure water for the normal static pressure support can be supplied through the supply valve, and it can be used for the static pressure support. The supply system of the hydrostatic water is supplied by different supply systems. Further, the loading means 8 and the carrying-out means 9 may be separately provided, or the two may be used in combination.

The fluid ejected from the injection hole 18 of the right static pressure pad 2 is gas The body, for example, compressed air is suitable, but it may be a compressed gas other than compressed air or a liquid such as water. Further, the number of the injection holes 18, the flow rate of the fluid, and the pressure can be appropriately changed. In general, if the set pressure of the fluid is increased, the flow rate is increased, and the difference between the suction holding state of the workpiece W and the flow rate of the fluid in the non-suction holding state is increased, and the permeation flow sensor 26 can easily grasp whether or not the workpiece W is Attractive to keep.

In addition, even when the diameter of the injection hole 18 is small, the larger the number of the injection holes 18, the larger the change in the total flow rate tends to be. Therefore, even when the number of the injection holes 18 is large, even if the set pressure of the fluid is lowered, it is possible to easily grasp whether or not the suction is maintained by the change in the flow rate.

The supply and stop of the fluid to the plurality of injection holes 18 may be integrally controlled by the common control unit, or the plurality of injection holes 18 may be controlled for each of the injection holes 18 or divided into a plurality of groups. In this case, the flow rate sensor 26, the pressure sensor 27, and the like may be provided integrally or separately or in groups according to the supply and stop control methods.

1, 2‧‧‧ static pressure pad

3, 4‧‧ ‧ gap

5, 6‧‧‧ grinding grinding stone

7‧‧‧ Carrier

8‧‧‧Relocation means

9‧‧‧Removal means

10, 11‧‧‧ Static pressure support surface

12.13‧‧‧ recess

14, 15‧‧ ‧ convex

16, 17‧‧ ‧ discharge trough

18‧‧‧Spray hole

21, 22‧‧‧ opening and closing control means

23‧‧‧ Static pressure water supply source

24‧‧‧Opening and closing control means

25‧‧‧Compressed air supply

26‧‧‧Flow sensor

27‧‧‧ Pressure Sensor

36‧‧‧ movable frame

37, 38‧‧‧ adsorption cup

W‧‧‧Workpiece

X1‧‧‧Progress to maintain position

X2‧‧‧Retirement position

Y1‧‧‧ forward end

Y2‧‧‧ Back end

Claims (13)

A two-face surface grinding method in which a thin plate-shaped workpiece supported by a pair of static pressure pads is rotated through a carrier while grinding both sides of the workpiece by a pair of grinding stones, which is characterized in that When the workpiece in the carrier is delivered, the static pressure pad from one side is ejected to the workpiece side, and the negative pressure generated by the Bernoulli effect at this time, the static pressure pad on the side The side attracts the workpiece in a non-contact manner. The two-plane grinding method of claim 1, wherein the workpiece sucked by the loading means reaches the static pressure pad on the one side of the advance holding position, and the fluid is ejected from the static pressure pad on the one side to the workpiece side. The static pressure pad side of one side attracts and holds the workpiece in a non-contact manner. In the two-plane grinding method of claim 2, the vacuum suction of the loading means is released immediately after the suction/holding of the workpiece on the static pressure pad side of the one side or the suction holding. The two-plane grinding method according to any one of claims 1 to 3, wherein the other of the static pressure pads is advanced to the advancement holding position, and the workpiece is clamped from both sides by the two static pressure pads, After the injection of the fluid of the static pressure pad on one side, a static pressure fluid is supplied to the two static pressure pads to statically support the workpiece. The two-plane grinding method according to any one of claims 1 to 3, wherein after the grinding of the workpiece, the supply of the static pressure fluid to the static pressure pads is stopped or the supply is stopped immediately after the supply is stopped. The side static pressure pad ejects the fluid and attracts the workpiece in a non-contact manner on the static pressure pad side of the one side. The two-plane grinding method of claim 5, wherein the static pressure fluid is supplied from the other static pressure pad immediately after the static pressure pad of the one side is attracted to hold the workpiece, or the suction is maintained, While the surface tension of the fluid is being affected, the workpiece is pressed toward the static pressure pad side of one side. The two-plane grinding method of claim 6, wherein the workpiece after grinding is clamped from both sides by the static pressure pad and the carrying-out means on the one side, and the workpiece is vacuum-adsorbed by the carrying-out means or vacuum-adsorbed Immediately thereafter, the suction holding of the static pressure pad on the one side is released, and the static pressure fluid is supplied from the static pressure pad on the one side to separate the workpiece from the static pressure pad on the one side. A two-plane grinding method according to claim 1 or 2, wherein the fluid is compressed air. A two-face surface grinder having: a carrier for rotating a thin plate-shaped workpiece; a pair of static pressure pads, the pair of static pressure pads statically supporting the workpiece in the carrier; a pair of grinding stones, the one Supporting the grinding stone by static pressure of the static pressure pad, grinding both sides of the rotating workpiece; and loading and unloading means, the loading and unloading means adsorbing the workpiece and performing between the pair of static pressure pads The loading and unloading is characterized in that the static pressure pad on one side has an injection hole for discharging a fluid to the workpiece side, and the negative pressure generated by the Bernoulli effect at this time is on the one side. The static pressure pad side attracts and holds the workpiece in a non-contact manner. The two-stage surface grinder of claim 9, wherein the injection hole is disposed at a plurality of positions in the circumferential direction, the circumferential direction including a defect with the workpiece The vicinity of the engaging portion of the carrier that is engaged with the mouth. A two-stage surface grinder as claimed in claim 9 or 10, wherein there is a sensor which confirms the suction retention of the workpiece based on a change in the flow rate or pressure of the fluid ejected from the injection hole. A two-stage surface grinder according to claim 9, wherein the static pressure pad on the one side has a plurality of the injection holes arranged equidistantly in the circumferential direction on the outer peripheral portion. A two-stage surface grinder according to claim 9, wherein each of the static pressure pads has a notch portion corresponding to the grinding stone, and the static pressure pad on the one side has an equidistant arrangement in a circumferential direction on a peripheral portion of the notch portion A plurality of the injection holes.