JP2002036078A - Double face grinding device for thin disk work - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a device capable of simultaneously and easily grinding both the faces of a thin disk work with a high machining quality and capable of reducing the size thereof. SOLUTION: This double face grinding device comprises a pair of grinding wheels 9, a work self-rotating means supportedly self-rotating a work W on a grinding position between grinding faces 9 so that the both ground surfaces of the work W face the ground faces 9a of the pair of stones 9, the outer periphery of the work W crosses the outer periphery of the ground faces 9a, and the center of the work W is positioned in the ground faces 9a, and a work storage and retrieval means. The self-rotating means comprises a static pressure type axial supporting means for supplying fluid to both machined surfaces of the work at the portion extended to the outside from a clearance between the stones to axially support the work W by the static pressure of the fluid in the state of non-contact with each other. The storage and retrieval means feeds the work W to a grinding position where the work W is supported by the static pressure type axial supporting means in the state of non-contact with each other, and carries out the work W from the grinding position.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an apparatus for grinding both sides of a thin disk-shaped work, and more particularly to an apparatus for simultaneously grinding both sides of a thin disk-shaped work such as a semiconductor wafer.

[0002]

2. Description of the Related Art As an apparatus for simultaneously grinding both surfaces of a work, a pair of rotating grinding wheels, which are arranged so that the grinding surfaces of the end surfaces face each other, are placed in a rotating disk-shaped carrier pocket. What passes through the work which has been used is conventionally known. In this case, the outer diameter (diameter) of the grinding surface of the grinding wheel
Must be larger than the outer diameter of the workpiece. Also,
In the carrier, a plurality of pockets are usually formed at equal intervals on a circumference close to the outer periphery, and a part of the carrier also enters between the pair of grinding wheels together with the wafer. The thickness must, of course, be smaller than the distance between a pair of grinding wheels during grinding, ie, the finished thickness of the work.

Incidentally, currently used semiconductor wafers have an outer diameter of about 200 mm (8 inches) and about 3 mm.
There is one with a thickness of 00 mm (12 inches), but the thickness (finished dimensions) is about 0.8 mm, and the thickness is extremely thin as compared with the outer diameter. When such a wafer is ground by the above-described apparatus, the outer diameter of the wafer is relatively large, so that the outer diameter of the grindstone increases, and the carrier that accommodates and rotates the wafer also increases. For this reason, the device becomes large. Further, since the thickness of the wafer is small, it is necessary to make the portion of the carrier between the grinding wheel and the wafer extremely thin. Grinding force acts on the part of the carrier, especially the pocket, that enters between the grinding wheels through the work contained in it, but when this part is made thinner, the strength decreases and the work can be moved smoothly. It becomes difficult. For this reason, it was conventionally difficult to grind both sides of the wafer.

[0004] A similar problem also occurs in the case of a thin disk-shaped work other than a wafer.

[0005]

SUMMARY OF THE INVENTION An object of the present invention is to provide an apparatus which can easily and simultaneously grind both surfaces of a thin disk-shaped work, has a high processing quality and can be miniaturized.

[0006]

According to the first aspect of the present invention, there is provided a pair of circular grinding surfaces which are disposed so as to be opposed to each other and are relatively rotatable in the axial direction and are rotated. The grinding wheel and the processing surfaces on both surfaces of the thin disk-shaped work face the grinding surfaces of the pair of grinding wheels, respectively, and the outer periphery of the work intersects the outer periphery of the grinding surface, and the center of the work is the grinding surface. A work rotation means for supporting the work at a grinding position between the grinding surfaces so as to be positioned in a plane, and a work loading / unloading means, and the work rotation means, A static pressure type axial support means for supplying a fluid to the processing surfaces on both surfaces of the portion of the work which is outside from the space and supporting the work in a non-contact manner in the axial direction by the static pressure thereof, and Support and rotate And a radial support drive means for,
The work loading / unloading means is adapted to supply the work to a grinding position where the work is non-contact supported by the static pressure type axial support means, and to carry out the work from the grinding position. It is a feature.

The work is supported at the grinding position by the axial support means and the radial support drive means of the work rotating means so that the outer periphery thereof intersects the grinding surface and its center is located within the grinding surface, The workpiece is rotated, and a pair of grinding wheels are rotated while the respective grinding surfaces are in contact with the respective processing surfaces of the work. As the grinding wheel rotates, the work surface of the work that is in contact with those grinding surfaces is ground, and the work rotates on its axis with the outer periphery of the work crossing the grinding surface and the center of the work positioned within the grinding surface By doing so, while the work makes one rotation, the entire surface of the work surface of the work passes between the grinding surfaces and comes into contact with the grinding surface. For this reason, it is possible to simultaneously grind the entire surface of both surfaces by simply rotating the work on the spot using a grinding wheel whose outer diameter is slightly larger than the radius of the work. It is only necessary to rotate the work on the spot, and it is not necessary to move it using a carrier etc. as in the past, so even a thin disk-shaped work can be easily and reliably ground,
Moreover, the size of the device can be reduced.

[0008] Since the axial support means supports the work in a non-contact manner by static pressure, the work can be reliably supported, and the processed surface of the finished work is not damaged and high quality can be obtained. A machined surface is obtained. Also,
Since the static pressure type axial support means only supplies fluid to both working surfaces of the work, the configuration of the apparatus can be simplified and downsized.

Therefore, according to the first aspect of the present invention, both surfaces of the thin disk-shaped work can be simultaneously and easily ground, the processing quality is high, and the apparatus can be downsized.

[0010] In the first aspect of the present invention, for example, as in the second aspect, the radial support driving means contacts at least two rollers for regulating the radial position of the work by contacting the outer periphery of the work. And at least one of these rollers is a drive roller for rotating the work.

[0011] Some semiconductor wafers have a positioning flat portion formed by cutting out one portion of the outer periphery in an arc shape, and others do not have the positioning flat portion.

[0012] When vertically grinding a complete circular work having no positioning flat portion formed thereon, a roller is brought into contact with two portions on the lower portion of the outer periphery of the work one by one, and at least one roller is contacted. By using these as drive rollers,
The work can be rotated while being supported at a fixed position in the radial direction.

When a workpiece having no positioning flat portion is horizontally supported and ground, grinding is performed on the outer periphery of the workpiece.
The rollers may be contacted one by one at a location, desirably as close as possible to the position where the outer periphery of the work is divided into three equal parts in the circumferential direction, and at least one roller may be used as a driving roller. With this configuration, the work can be reliably supported at a fixed position in the radial direction and can be smoothly rotated.

In the case where a workpiece having no positioning flat portion is vertically supported and ground, the lower portion of the outer periphery of the workpiece is ground in the same manner as in the case where the workpiece is horizontally supported and ground. It is preferable that one roller is brought into contact with a total of three places, i.e., two places and one place of the upper part, so that at least one is a drive roller.

In the case of vertically grinding a workpiece having a positioning flat portion formed thereon, two rollers are provided at two lower portions of the outer periphery of the workpiece in the circumferential direction of the flat portion. The work can be supported and rotated at a fixed position in the radial direction by making contact with a space slightly larger than the size and using at least two as drive rollers.

In the case where a workpiece having a positioning flat portion is horizontally supported and ground, grinding is performed at three positions on the outer periphery of the workpiece, preferably at a position close to a position at which the outer periphery of the workpiece is divided into three equal parts in the circumferential direction. In this case, two rollers may be brought into contact with each other at an interval slightly larger than the circumferential dimension of the flat portion, and at least two rollers may be used as drive rollers. With this configuration, the work can be reliably supported at a fixed position in the radial direction and can be smoothly rotated. In this case, two rollers are provided at two of the three locations, and one roller is provided at the remaining one location so as to be movable in the radial direction of the work, and is provided by an elastic force of a spring or the like. You may make it contact the outer periphery of a workpiece | work.

When the workpiece having the positioning flat portion formed thereon is vertically supported and ground, similarly to the case where the workpiece is horizontally supported and ground, the lower portion of the outer periphery of the workpiece is ground. It is desirable that the rollers are brought into contact with each other at a total of three locations, i.e., two locations and one location of the upper portion, and at least two of them are used as drive rollers.

In the first aspect of the present invention, for example, as in the third aspect, the grinding wheel has a cup shape in which an annular end surface of an outer peripheral portion is a grinding surface, and the radial support driving means includes: Comprising at least two rollers that contact the outer periphery of the work and regulate the radial position of the work,
One of these rollers is attached to the center of the inside of the grinding surface of the one grinding wheel so as to be rotatable around the axis of the grinding wheel, and the one of the workpieces located between the grinding wheels. A roller that contacts the outer periphery of the portion, and the other one is a roller that rotates between the grinding wheels and the outer periphery of the portion of the work that is out of the axial support means. One of them is a drive roller for rotating the work.

With this configuration, the work can be reliably supported in the radial direction by a small number of rollers, and the work can be surely rotated by the driving rollers. Also, since one of the rollers is attached to the center of the inside of the grinding surface of the grinding wheel and does not protrude outside the grinding surface of the grinding wheel, the size of the apparatus can be reduced accordingly.

In the first aspect of the present invention, for example, as in the fourth aspect, the outer periphery of a portion of the work that is protruded between the grinding wheels and out of the axial support means. , And at least two pairs of rollers for regulating the radial position of the work in contact with each other.
The distance between the rollers is larger than the circumferential dimension of the positioning flat portion formed on the outer periphery of the work, and at least two of these rollers are drive rollers for rotating the work.

In this way, it is possible to support and rotate a work in which a positioning flat portion is not formed, as well as a work in which the positioning flat portion is formed, at a fixed position in the radial direction.

According to a fifth aspect of the present invention, there is provided a pair of grinding wheels which are arranged so that the circular grinding surfaces of the end faces thereof are opposed to each other and are relatively movable in the axial direction and are rotated. The work is performed so that the processing surfaces on both sides respectively face the grinding surfaces of the pair of grinding wheels, and the outer periphery of the work intersects the outer periphery of the grinding surface and the center of the work is located in the grinding surface. A work rotating means supported and rotated at a grinding position between the grinding surfaces, and a work carry-in / out means are provided, and the work rotating means is provided for the work coming out from between the grinding wheels. A static pressure type axial support means for supplying a fluid to the processing surfaces on both sides of the portion and supporting the work in a non-contact manner in the axial direction by a static pressure thereof, and a shoe which comes into contact with two predetermined positions on the outer periphery of the work; The grinding wheel The work is rotated by the rotational force of the shoe and the action of the shoe, and the work carry-in / out means supplies the work to a grinding position where the work is supported in a non-contact manner by the hydrostatic axial support means. And the work is carried out from a grinding position.

Also in the case of the invention of claim 5, similarly to the case of the invention of claim 1, both surfaces of the thin disk-shaped work can be simultaneously and easily ground, the processing quality is high, and the apparatus can be downsized. is there. In addition, the work can be supported and rotated in the radial direction with only two shoes, and the configuration of the device can be simplified and downsized. Further, since the work can be rotated by using the rotational force of the grinding wheel, no other power source is required, and the configuration of the apparatus can be simplified and downsized from this point as well.

[0024]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment in which the present invention is applied to double-side grinding of a semiconductor wafer will be described below with reference to the drawings.

FIGS. 1 to 3 show a first embodiment, and FIG. 1 shows the entire structure of the double-side grinding apparatus. The first embodiment is directed to a work on which a positioning flat portion is not formed. The double-sided grinding machine is obtained by adding a work rotating device (2) as a work rotating means to a horizontal shaft double-sided surface grinding machine (1), and details of the rotating device (2) are shown in FIGS. 2 and 3. I have. In the description of this embodiment,
The front side of FIG. 1 is the front, the back side is the rear, and the left and right when viewed from the front to the rear, that is, the left and right of FIG.

The grinding machine (1) comprises a horizontal bed (3) and left and right grinding heads (4) mounted on the upper surface of the bed (3).
(5) is provided. Although not shown in detail, the grindstone heads (4) and (5) are fixed to the bed (3) so that the front and rear and vertical angles can be adjusted independently of each other.
Within each grinding wheel head (4) (5), a horizontal grinding wheel axis (6)
(7) is rotatably supported. The axes of the left and right wheel axes (6) and (7) are on one common horizontal line extending in the left and right direction, and each wheel axis (6) (7) is positioned with respect to the respective wheel head (4) (5). It can be moved left and right. A cup-shaped left grinding wheel (8) is fixed to the tip of the grinding wheel shaft (6) projecting to the right from the left grinding wheel head (4).
A right-side grinding wheel (9) of the same shape and dimensions is fixed to the tip of the grinding wheel shaft (7) projecting further to the left. The annular vertical right end surface of the left grinding wheel (8) is a left circular grinding surface (8a), and the annular vertical left end surface of the right grinding wheel (9) is a right circular grinding surface (9a).
These ground surfaces (8a) (9a) face each other in a state of being parallel to each other. In the case of this embodiment, the outer circumferences of the grinding wheels (8) and (9) and the outer circumferences of the grinding surfaces (8a) and (9a) coincide. Left and right wheel axes (6) (7)
Is moved in the left-right direction, whereby the left and right grinding wheels (8), (9) relatively move in the left-right direction, that is, in the axial direction. The left and right grinding wheel shafts (6) and (7) are rotated at the same speed in the same direction (counterclockwise as viewed from the left side) by suitable driving means (not shown). The other parts of the grinding machine (1) can be configured in the same manner as a known horizontal-axis double-ended surface grinding machine.

The rotating device (2) is a work (wafer) (W)
The machined surfaces (a) and (b) on both sides face the left and right ground surfaces (8a) and (9a), and the outer periphery of the work (W) is the ground surface (8a) (9a).
The center (c) of the workpiece (W) intersects the outer circumference of the grinding surface (8a)
The workpiece (W) is placed on the left and right grinding surfaces (8
a) It is vertically supported and rotated between (9a), and is provided on the left grinding wheel head (4) and the right grinding wheel shaft (7).

When viewed from behind, the upper surface of the left grinding wheel head (4)
A letter-shaped base (10) is fixed, and a vertical support plate (11) projecting rightward from the grindstone head (4) is fixed to the upper right side of the base. A left side surface of a vertical thick plate-shaped static pressure support block (12) having a front-rear width and a height larger than the left and right thicknesses is fixed to a right end portion of the support plate (11). The front part of the block (12) projects below the support plate (11),
Its lower part projects further forward. This protruding part (1
The lower edge of 2a) is formed in a concave arc shape with a diameter slightly larger than the outer diameter of the grindstones (8) and (9).
Located just above the rear part of the A slit (13) is formed in the front portion including the projecting portion (12a) of the block (12) over the entire height and reaching the front edge.
The lateral width of the slit (13) is slightly larger than the thickness of the work (W). A static pressure groove (16) is formed in the projecting portion (12a) of the block (12) on the opposite surfaces of the left and right walls of the slit (13). An air supply hole (17) communicating with the groove (16) is formed in the wall on both sides of the slit (13) of the protruding portion (12a),
Air supply hose (1) is inserted into this hole (17) from outside the block (12).
8) and (19) are connected. Then, through a hose (18) (19) and a hole (17) from an air supply device (not shown), a groove (1
Air is supplied to 6).

The support block (12) is used to
(W) constitutes a hydrostatic axial support means for supporting the non-contact in the axial direction.

A grinding wheel head (4) is provided on the lower right side of the base (10).
A support member (20) projecting further to the right is fixed, and a drive roller (21) is attached to the support member (20) so as to be rotatable about a horizontal axis in the left-right direction. A drive electric motor (22) is also attached to the support member (20), so that the drive roller (21) can be rotated clockwise as viewed from the left side. The left and right width of the drive roller (21) is larger than the thickness of the work (W), and the drive roller (21) is located below the rear side of the slit (13) of the protruding portion (12a) of the block (12) and has a grinding wheel (8) (9). ) Is located on the rear side of the grinding wheels (8) and (9) slightly above the axis.

A small-diameter portion (7a) is formed at the left end of the right-hand grinding wheel shaft (7) and penetrates a disk-shaped portion at the right end of the grinding wheel (9) and extends to the left, and is located inside the grinding surface (9a). At the left end of the small-diameter portion (7a), a guide roller (driven roller) (23) having an outer diameter smaller than the inner diameter of the grinding surface (9a) is allowed to freely rotate around the axis of the grinding wheel shaft (7). Installed. The right end of the guide roller (23) is located slightly to the right (inside) of the grinding surface (9a).
The guide roller (23) protrudes leftward from the ground surface (9a), and the amount of protrusion is larger than the thickness of the work (W). When the left and right grinding wheels (8) and (9) are in the grinding operation position, the left end of the guide roller (23) is positioned inside the grinding surface (8a) of the left grinding wheel (8).

Although not shown in detail, the grinding wheel head (4)
A horizontal support plate (24) projecting above the front part of the grinding wheel shaft (6) on the right side is fixed to an appropriate place of the base (10), and is mounted on the upper surface thereof by a suitable actuator (25) such as an air cylinder. A moving member (26) that is moved in the front-rear direction is attached. A support rod (27) extending horizontally horizontally is fixed to the moving member (26), and a holding roller (driven roller) (28) is idled around the horizontal axis in the left-right direction at the rear end of the support rod (27). It is attached so that it can be done. The lateral width of the press roller (28) is larger than the thickness of the work (W). Presser roller (28)
Is switched between the operating position of the rear end shown by the solid line in FIG. 3 and the standby position of the front end shown by the dashed line in FIG. 3 by the movement of the moving member (26).
a) The grindstones (8) and (9) that are located just above the slit (13) at the front of and that are away from the protruding part (12a) at the standby position.
Is located above the front portion of the vehicle.

The work (W) is held vertically by the drive roller (2).
It is placed on 1) and the guide roller (23), and is supported at the grinding position. At this time, about half of the upper part of the work (W) enters the slit (13) of the protruding part (12a) of the block (12), and the lower part of the work (W) that comes out under the block (12) Two portions on the outer periphery of the portion contact the drive roller (21) and the guide roller (23). Further, the upper portion of the work (W) protrudes from the protruding portion (12a), and the second guide roller (28) switched to the operating position comes into contact with the outer periphery of this portion.

The driving roller (21), the guide roller (23) and the pressing roller (28) constitute a radial support driving means for supporting and rotating the work (W) in the radial direction.

In the case of this embodiment, the outer diameter of the grindstones (8) and (9) is slightly larger than the sum of the outer diameter of the work (W) and the outer diameter of the guide roller (23). The center (c) of W) is located between the outer periphery and the inner periphery of the upper part of the grinding surfaces (8a) (9a).

Although the detailed illustration is omitted, the grinding device includes:
An autoloader (29) is provided as work loading / unloading means for automatically loading / unloading the workpiece (W) into / from the rotation device (2).

In the above-mentioned grinding apparatus, the work of grinding the work (W) is performed, for example, as follows.

During the grinding operation, the left and right grinding wheels (8) and (9) are constantly rotating, and air is constantly supplied to only the block (12) (16). At the start of the operation, the left and right grindstones (8) and (9) have moved to the standby positions slightly left and right from the grinding operation position, and the holding roller (28) has moved to the standby position. In this state, the work (W) is supplied between the left and right grinding stones (8) and (9) through the slit (13) of the block (12) while the upper edge of the work (W) is gripped by the autoloader (29). And placed on the drive roller (21) and the guide roller (23). When the work (W) is placed on the rollers (21) and (23), the holding roller (28) is moved to the operating position and contacts the outer periphery of the work (W),
The autoloader (29) releases the work (W) and moves to the upper standby position. The work (W) is supported in a non-contact manner in the axial direction by the static pressure of air supplied to the groove (16) of the block (12), and is supported in the radial direction by the rollers (21) (23) (28). And is supported at a predetermined grinding position.

When the work (W) is supported at the grinding position, the drive roller (21) starts rotating. The work (W) is rotated about its center at the grinding position by the frictional force between the drive roller (21) and the outer periphery of the work (W).

When the work (W) starts rotating, the grinding wheel (8)
(9) are moved in the direction approaching each other, and the grinding surface (8a)
(9a) is brought into contact with the corresponding processing surfaces (a) and (b). As a result, the lower part of the work (W) is sandwiched between the grindstones (8) and (9),
The outer periphery of the work (W) intersects the outer periphery of the grinding surfaces (8a) (9a), and the center (c) of the work (W) is located within the grinding surfaces (8a) (9a).
The grindstones (8) and (9) are moved to a predetermined grinding work position determined by the finished dimensions of the work (W), and stopped at that position for a predetermined time. In the meantime, as the grindstones (8) and (9) rotate, the processing surfaces (a) and (b) of the work (W) in contact with the ground surfaces (8a) and (9a) are ground, and the work ( (W) crosses the outer circumference of the grinding surface (8a) (9a) and the center of the work (W)
Work (W) with (c) positioned inside the grinding surface (8a) (9a)
Is rotating, the work (W) rotates once,
The entire surface of the work surface (a) (b) of the work (W) passes between the grinding surfaces (8a) (9a) and comes into contact with the grinding surfaces (8a) (9a), and as a result, the work (W) During several rotations, the entire surfaces of both processing surfaces (a) and (b) are simultaneously ground.

When the grinding of the work (W) is completed, the grinding wheel (8)
(9) moves away from the work (W) and further moves to the left and right standby positions. When the grindstones (8) and (9) move away from the work (W), the drive roller (21) is stopped, whereby the work (W) also stops rotating. When the work (W) stops rotating, the upper edge of the work (W) is gripped by the autoloader (29),
The presser roller (28) is moved to the standby position,
(W) is carried out above the slit (13) of the block (12) by the autoloader (29). Thereafter, the work (W) to be ground next is carried into the grinding position as described above. Thereafter, the above operation is repeated to perform grinding one after another.

In the case of the first embodiment, a vertical work (W)
Receives downward force due to gravity, and the whetstones (8) and (9) rotate counterclockwise when viewed from the left side, and the part of the grinding surface (8a) (9a) that moves diagonally downward and The work (W) comes into contact with the work (W), and the work (W)
Drive roller in the direction receiving the downward diagonal force
(21) is pressed and rotated reliably. Also,
The work (W) receives a diagonally forward and downward force by the drive roller (21) and is pressed against the guide roller (23) in that direction. The work (W) is composed of two rollers (21) (2
According to 3), it is supported and rotated at a certain grinding position. Therefore, the upper pressing roller (28) is not always necessary. However, if the presser roller (28) is
(W) can be prevented from floating, and can be reliably rotated at the grinding position while being supported.

Normally, the left and right grinding wheels (8) and (9) are rotated at the same speed as in the above embodiment. For example, it is desired to change the grinding allowance distribution of the left and right processing surfaces (a) and (b). In some cases,
In some cases, the grinding speed can be changed by changing the rotation speed of the left and right grinding wheels (8) and (9). It is also possible to rotate the left and right grinding wheels (8) and (9) in opposite directions to perform grinding.

FIGS. 4 to 6 show a second embodiment, and FIG. 4 shows the entire configuration of the double-side grinding apparatus. The second embodiment is directed to a work on which a positioning flat portion is not formed. The double-sided grinding machine is obtained by adding a work rotating device (80) as a work rotating means to a horizontal-axis double-ended surface grinding machine (1), and details of the rotating device (80) are shown in FIGS. I have. In the description of this embodiment,
The front side of FIG. 4 is the front, the back side is the rear, and the left and right when viewed from the front, that is, the left and right of FIG.

The grinding machine (1) is the same as that of the first embodiment, and the corresponding parts are denoted by the same reference numerals. In the case of this embodiment, the left and right grinding wheels (8) and (9) are rotated at the same speed in the same direction (counterclockwise as viewed from the left).

The rotation device (80) is provided on the bed (3) and the left wheel head (4).

On the upper surface of the left grinding wheel head (4), a grinding wheel head
(4) A base (81) projecting to the right side is fixed, and a static pressure support block (8) similar to that of the first embodiment is attached to the right end thereof.
2) The upper part is fixed. The front part of the block (82) protrudes below the base (81), and the lower front edge of the block (82) including this protruding part (82a) has a diameter slightly smaller than the outer diameter of the grindstones (8) and (9). It is formed in a large concave arc shape, and this arc portion is located immediately behind the grindstones (8) and (9). A slit (83) is formed in the front portion of the block (82) including the protruding portion (82a), extending over the entire height and reaching the front edge. The lateral width of the slit (83) is slightly larger than the thickness of the work (W). Static pressure grooves (84) are formed in the lower surface of the block (82) on the opposite surfaces of the left and right walls of the slit (83), and the grooves (84) in each wall are air-permeable through the air supply holes (85). Connected to supply hoses (86) (87).

Bed (3) between left and right whetstone heads (4) (5)
A vertical support plate (88) that extends in the front-rear direction and the up-down direction is fixed to the upper surface of the device. The support plate (88) has a substantially concave shape when viewed from the left and right directions, and its front protruding part (88a) is
(8) Extend the front side of (9) to near its upper edge, and
8b) extends behind the grinding wheels (8) and (9) to near the middle of its height. The first shoe (8) which comes into contact with the outer periphery of the work (W) and receives it at the upper end of the rear projecting portion (88a) of the support plate (88).
9) is fixed. The surface of the shoe (89) for receiving the work (W) faces obliquely upward on the front side, and the lateral width thereof is larger than the thickness of the work (W). The shoe (89) is located just behind the slit (83) of the projecting portion (82a) of the block (82) and
(8) It is located slightly lower than the axis of (9). Support plate
(88) The upper end of the front protruding part (88a) and the rear protruding part (88
b) A block-shaped support member (90) (91) is fixed diagonally on the lower left side of the lower part of (b), and is movable into a bottomed hole (92) formed on the rear downward surface of the front support member (90). A member (93) is movably fitted. The movable member (93) is screwed into a bolt (94) rotatably inserted from the outside into a through hole in the bottom wall of the hole (92), and the movable member (93) is rotated by rotating the bolt (94).
The position of (93) is adjusted. Both ends of the steel band-shaped second shoe (95) are fixed to the movable member (93) and the support member (91) on the rear side, and the movable member (93) is pulled obliquely forward with the bolt (94), The shoe (95) is held in tension. The thickness of the second shoe (95) in the left-right direction is the work
The width of the shoe (95) is slightly smaller than the thickness of the work (W), and the narrow slanting upward surface of the shoe (95) comes into contact with and receives the outer periphery of the work (W). The position of the second shoe (95) in the left-right direction substantially coincides with the center position in the left-right direction of the slit (83) of the block (82), and the shoe (95) is located between the left and right whetstones (8) and (9). It extends obliquely from the rear lower part to the front upper part, passing below the block (82) and below the axis of the grindstones (8) and (9).

Although not shown, the grinding apparatus is provided with the same autoloader as in the first embodiment.

In the above-described grinding apparatus, the work of grinding the work (W) is performed, for example, as follows.

First, a work (W) is
But, through the slit (83) of the block (82),
It is supplied between (8) and (9) and is put on two shoes (89) and (95). As a result, about half of the front side of the work (W) enters between the left and right grinding wheels (8) and (9), and about half of the rear side enters the lower part of the slit (83), and the work (W) )
The block (82) is supported in a non-contact manner in the axial direction by the static pressure of the air supplied to the groove (84), and is supported in the radial direction by the shoes (89) and (95) and is supported at a predetermined grinding position. . At this time, the rear part of the work (W) protruding from the block (82) and slightly below the center (c) is received by the first shoe (89), and the work (W) is protruded from the block (82). The lower part of the work (W) between the left and right whetstones (8) and (9),
A part slightly forward of the center (c) is received by the second shoe (95). When the work (W) is placed on the shoes (89) and (95), the autoloader separates the work (W) and moves to the upper standby position.

When the work (W) is supported at the grinding position, the grindstones (8) and (9) are moved in directions approaching each other.
The ground surfaces (8a) and (9a) are brought into contact with the corresponding processing surfaces (a) and (b). As a result, the front part of the work (W) is
The outer periphery of the work (W) intersects the outer periphery of the grinding surface (8a) (9a), and the center (c) of the work (W) is the outer periphery and inner periphery of the rear part of the grinding surface (8a) (9a). Located between. Also, at this time, since the outer periphery of the work (W) is only in contact with the shoes (89) and (95) and there is nothing to prevent the rotation of the work (W), the work (W) is moved in the same direction. It receives rotational force from the whetstones (8) and (9) that are rotating on the shoe (89) and (95) and is pressed against the shoe (89).
Rotate while sliding against (95). As a result, the work (W) rotates around its center (c) in the same direction as the grindstones (8) and (9) (counterclockwise as viewed from the left). Whetstone (8) (9)
Is moved to a predetermined grinding position determined by the finished dimensions of the work (W), and stopped at that position for a predetermined time. In the meantime, by the rotation of the grindstones (8) and (9) and the rotation of the work (W) thereby, the same as in the first embodiment,
The entire processing surfaces (a) and (b) on both surfaces of the work (W) are simultaneously ground.

When the grinding of the work (W) is completed, the grinding wheel (8)
(9) moves away from the work (W) and further moves to the left and right standby positions. When the grindstones (8) and (9) move away from the work (W), the rotational driving force on the work (W) is lost, so the work (W)
Also stops spinning. When the rotation of the work (W) stops, the work (W) is carried out through the slit (83) of the block (82) by the autoloader (29).

The other points are the same as in the first embodiment.

In the above embodiments, air is supplied to the static pressure type axial support means. However, other fluids such as water used for grinding may be supplied.

In the first and second embodiments, the work rotation device may reciprocate in a direction parallel to the grinding surface while rotating the work. In this case, the configuration of the reciprocating means is arbitrary, and may be one that reciprocates both the hydrostatic axial support means and the radial support drive means, or one that reciprocates only the radial support drive means. It may be. Since the static pressure type axial support means supports the work in a non-contact manner by static pressure, without reciprocating the work, even if only the radial support drive means is reciprocated,
The work can be reciprocated.

In each of the embodiments described above, the horizontal axis double-sided grinding apparatus in which the axis of the grinding wheel is horizontal is shown. However, a vertical type in which the axis of the grinding wheel is vertical with the same configuration as described above. You can also.

The present invention can also be applied to the grinding of a thin disk-shaped work other than a semiconductor wafer.

[Brief description of the drawings]

FIG. 1 is a schematic front view of a double-side grinding device showing a first embodiment of the present invention.

FIG. 2 is a partially cutaway front view showing a part of the work rotation device of FIG. 1 in an enlarged manner.

FIG. 3 is a sectional view taken along line III-III of FIG. 2;

FIG. 4 is a schematic front view of a double-side grinding device according to a second embodiment of the present invention.

FIG. 5 is a partially cutaway front view showing a main part of the work rotating device of FIG. 4 in an enlarged manner.

FIG. 6 is a sectional view taken along the line VI-VI in FIG. 5;

[Explanation of symbols]

 (2) Work rotation device (work rotation means) (8) (9) Grinding wheel (8a) (9a) Grinding surface (12) Static pressure support block (21) Drive roller (23) Guide roller (28) Holding roller ( 80) Work rotation device (82) Static pressure support block (89) (95) Shoe

 ────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Koichi Ueda 2-34, Minamiuematsucho, Yao-shi, Osaka Koyo Machinery Co., Ltd. F-term (reference) 3C016 CA07 CB06 CE05 3C043 BC06 CC04 CC11 DD05

Claims (5)

[Claims] 1. A pair of grinding wheels, which are arranged so that the circular grinding surfaces of the end surfaces face each other and are relatively movable in the axial direction and are rotated, and the processing surfaces of both surfaces of a thin disk-shaped work are provided. The work is interposed between the grinding surfaces such that the outer periphery of the work intersects the outer periphery of the grinding surface and the center of the work is located within the grinding surface while facing the grinding surfaces of the pair of grinding wheels. A work rotation means supported and rotated at a grinding position, and a work loading / unloading means, wherein the work rotation means is configured to process both surfaces of a portion of the work that is outside from between the grinding wheels. A static pressure type axial support means for supplying fluid to the surface and supporting the work in a non-contact manner in the axial direction by the static pressure, and a radial support drive means for supporting and rotating the work in the radial direction,
The work loading / unloading means is adapted to supply the work to a grinding position where the work is non-contact supported by the static pressure type axial support means, and to carry out the work from the grinding position. Features Double-sided grinding machine for thin disk-shaped work. 2. The apparatus according to claim 2, wherein said radial support driving means includes at least two rollers which contact the outer periphery of said work to regulate a radial position of said work, and at least one of said rollers is provided with said work. 2. The double-side grinding apparatus for a thin disk-shaped work according to claim 1, wherein the apparatus is a driving roller for rotating the workpiece. 3. The grinding wheel has a cup-like shape in which an annular end surface of an outer peripheral portion is a grinding surface, and the radial support driving means contacts the outer periphery of the work and adjusts the radial direction of the work. At least two rollers for regulating the position are provided, and one of these rollers is mounted on a center inside the grinding surface of the one grinding wheel so as to be rotatable around the axis of the grinding wheel. A roller that contacts the outer periphery of the portion of the work that is located between the grinding wheels, and another is a roller that contacts the outer periphery of the portion of the work that is between the grinding wheels and out of the axial support means. 2. A double-sided grinding apparatus for a thin disk-shaped work according to claim 1, wherein a roller which rotates in contact with the outer periphery is used, and one of said rollers is a drive roller for rotating said work. 4. The radial support driving means regulates the radial position of the work by contacting between the grinding wheels and the outer periphery of the portion of the work protruding from the axial support means. At least two pairs of rollers are provided, and the distance between the two rollers of each pair is greater than the circumferential dimension of a positioning flat portion formed on the outer periphery of the work, and at least two of these rollers are 2. The double-side grinding apparatus for a thin disk-shaped work according to claim 1, wherein the apparatus is a drive roller for rotating the work. 5. A pair of grinding wheels, which are arranged so that the circular grinding surfaces of the end surfaces thereof face each other and are relatively movable in the axial direction and are rotated, and the processing surfaces of both surfaces of the thin disk-shaped work are provided. The work is interposed between the grinding surfaces such that the outer periphery of the work intersects the outer periphery of the grinding surface and the center of the work is located within the grinding surface while facing the grinding surfaces of the pair of grinding wheels. A work rotation means supported and rotated at a grinding position, and a work loading / unloading means, wherein the work rotation means is configured to process both surfaces of a portion of the work that is outside from between the grinding wheels. A static pressure type axial support means for supplying fluid to the surface and supporting the work in a non-contact manner in the axial direction by the static pressure thereof; and a shoe for contacting two predetermined locations on the outer periphery of the work, and rotating the grinding wheel. Force and said The work is rotated by the action of the workpiece, and the work loading / unloading means supplies the work to a grinding position where the static pressure type axial support means supports the work in a non-contact manner, and performs grinding. A double-sided grinding apparatus for a thin disk-shaped work, wherein the work is carried out from a position.