JPH10180602A - Double grinding device for disklike sheet workpiece - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a small-sized device for grinding both surfaces of a disklike sheet workpiece simultaneously with ease. SOLUTION: A double grinding device comprises a pair of grinding wheels 12 and 13, and a workpiece rotating device which supports and rotates a workpiece W at its grinding position where the machined surfaces on both sides of the workpiece W are opposed to the circular grinding surfaces of the grinding wheels 12 and 13 and part of the circumference of the workpiece W and the center C thereof are situated inside the circumferences of the grinding surfaces. The workpiece rotating device comprises guide rollers 17 and 18 of numbers at least three adapted to rotate upon the contact with the circumference of the workpiece W situated outside the grinding wheels 12 and 13, a pair of driving belts 15 and 16 adapted to contact with the machined surfaces of the workpiece W at two positions situated outside the grinding wheels 12 and 13 to feed or rotate it, and pressure rollers 19 and 20 for pressing the driving belts 15 and 16 onto the machined surfaces of the workpiece W from the sides of the driving belts 15 and 16 not contacting with the workpiece W such that the driving belts 15 and 16 hold the workpiece W therebetween.

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 a device for simultaneously grinding both surfaces of a disk-shaped work, a rotating disk-shaped carrier is interposed between a pair of rotating grinding wheels arranged such that the grinding surfaces of the end surfaces face each other. It is conventionally known to pass a work in a pocket. In this case, the outer diameter (diameter) of the grinding surface of the grinding wheel must be larger than the outer diameter of the work. In addition, a plurality of pockets are usually formed on the carrier 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 of the carrier must, of course, be smaller than the distance between the pair of grinding wheels during grinding, ie, the finished thickness of the workpiece.

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 simultaneously and easily grind both surfaces of a thin disk-shaped work and can reduce the size.

[0006]

SUMMARY OF THE INVENTION An apparatus according to the present invention comprises a pair of grinding wheels which are arranged and rotated so that circular grinding surfaces on end faces thereof are opposed to each other and relatively movable in an axial direction. Grinding stone and the processing surfaces on both surfaces of the thin disk-shaped work are respectively opposed to the grinding surfaces of the pair of grinding whetstones, and a part and the center of the outer periphery of the work are located inside the outer periphery of the grinding surface. Work rotation means for rotating the work while supporting the work at a grinding position between the grinding surfaces, the work rotation means, a radial support means for regulating the radial position of the work, An axial support means for regulating an axial position of the work, wherein at least three of the radial support means rotate in contact with the outer periphery of the work protruding outside from between the grinding wheels. of A pair of drive belts comprising an id roller, wherein the axial support means rotates by rotating the work by contacting and moving at two places on a processing surface of the work which is out of between the grinding wheels, A press roller is provided, which presses the workpiece to a processing surface of the workpiece from the opposite side of the drive belt so as to sandwich the workpiece between the drive belts.

The work is supported at the grinding position by the radial support means and the axial support means of the work rotating means so that a part and the center of the outer circumference are located inside the outer circumference of the grinding surface, and the work is rotated. And a pair of grinding wheels are rotated with their respective grinding surfaces in contact with the respective processing surfaces of the work. By rotating the grinding wheel,
The work surface of the workpiece that is in contact with the ground surface is ground, and the workpiece rotates by itself while a part of the outer periphery and the center are positioned inside the outer periphery of the ground surface.
During rotation, the entire work surface of the workpiece 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 as in the past.Thus, even a thin disk-shaped work can be easily and reliably ground, and the size of the device is small. Is possible. In addition, the entire processing surface of the work can be ground using a grinding wheel whose outer diameter of the grinding surface is slightly larger than the radius of the work, and it is necessary to use a large grinding wheel whose outer diameter of the grinding surface is larger than the outer diameter of the work. Because there is no, from this point,
The size of the device can be reduced.

Furthermore, the work can be reliably supported and rotated by only a small number of rollers constituting the radial support means and the axial support means and a pair of drive belts, thereby simplifying the structure of the apparatus and reducing the size of the apparatus. Is possible.

Therefore, according to the apparatus of the present invention, both sides of the thin disk-shaped work can be simultaneously and easily and reliably ground, and the structure of the apparatus can be simplified and downsized.

[0010] For example, the pair of drive belts are arranged in parallel with each other so that the surface of a work supporting portion in contact with the work faces upward, and the driving state of the pair of drive rollers is controlled by the work supporting portion. Are moved in the same carry-in direction to each other and carry the work placed thereon to the grinding position, and the work supporting portion moves in the same carry-out direction to carry the work placed thereon. A work unloading state in which the work is unloaded from the processing position, and a work rotation state in which the work support unit moves in the opposite direction to each other and rotates the work mounted thereon is rotated,
The press roller is configured to move up and down between a standby position on the drive belt that is separated from the work above the work, and an operation position on the drive belt that is pressed against the work,
At least two fixed guide rollers, wherein the axial support means abuts against and stops the outer periphery of the front portion in the moving direction of the workpiece moved by the pair of drive belts in the workpiece carrying state; At least one movable guide roller that abuts on the outer periphery of a portion of the work in the movement direction rear side stopped by the fixed guide roller, wherein the movable guide roller is more than the work on the drive belt. The apparatus moves up and down between a standby position separated upward and an operation position in contact with the outer periphery of the work on the drive belt.

With this configuration, the work is simply placed on the surface of the upwardly directed work support portion of the drive belt, and thereafter, the work is carried into the grinding position by the work support portion of the drive belt, and the work is then moved to that position. Can be rotated to perform the grinding process, and the finished workpiece can be carried out from the grinding position. Since the work can be loaded and unloaded by the drive belt for rotating the work, the configuration of the apparatus can be simplified and downsized.

In this case, for example, the work supporting portions of the pair of drive belts are guided by a guide member disposed therebelow.

With this configuration, the pressing force of the pressing roller can be received by the guide member, and the drive belt is not deformed, so that the work can be reliably supported at a fixed position in the axial direction.

In the above case, for example, the pressing roller and the movable guide roller are mounted on the same elevating member so as to move up and down in synchronization with each other. In this case, only one elevating member is provided. The lifting roller and the movable guide roller can be raised and lowered at the same time, and the configuration and operation of the apparatus can be simplified and downsized.

[0015]

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.

1 to 3 show a first embodiment, and FIG. 1 shows the entire configuration of a double-side grinding device. The first embodiment is directed to a work on which a positioning flat portion is not formed. Double-sided grinding machine is a vertical double-sided surface grinding machine
A work rotation device (2) as work rotation means is added to (1), and details of the rotation device (2) are shown in FIGS. 2 and 3. In the description of this embodiment, the left side of FIG. 1 is the front, the right side is the rear, and the left and right when viewed from the front is the left and right.

The grinding machine (1) is mounted on a horizontal base (3) fixed to the floor (A), a column (4) extending vertically upward from the rear of the base (3), and a front surface of the column (4). It has upper and lower slides (5) and (6) and upper and lower whetstone heads (7) and (8) fixed to the front surface of each slide (5) and (6). Each slide
(5) and (6) can be vertically moved along the column (4) independently of each other by appropriate driving means (not shown). Vertical grinding wheel shafts (10) and (11) are rotatably supported by the upper and lower grinding wheel heads (7) and (8), respectively. The axes of the upper and lower grinding wheel axes (10) and (11) are on one common vertical line. A cup-shaped upper grinding wheel (12) is fixed to the lower end of the upper grinding wheel shaft (10) projecting below the lower surface of the upper grinding wheel head (7), and protrudes above the upper surface of the lower grinding wheel head (8). A lower grinding wheel (13) having the same shape and the same dimensions as the lower grinding wheel (13) is fixed to the upper end of the lower grinding wheel shaft (11). The annular horizontal lower surface of the upper grinding wheel (12) is an upper circular grinding surface (12a), and the annular horizontal upper surface of the lower grinding wheel (13) is a lower circular grinding surface (13a). (12a) and (13a) face each other in a state of being parallel to each other. In the case of this embodiment, the outer circumference of each grinding wheel (12) (13) and the outer circumference of each grinding surface (12a) (13a) coincide. Up and down slide
By moving at least one of (5) and (6) in the vertical direction, the upper and lower grinding wheels (12) and (13) relatively move in the vertical direction, that is, in the axial direction. The upper and lower grinding wheels (10) and (11) are rotated at the same speed in opposite directions by appropriate driving means (not shown). As a result, the upper and lower grinding wheels (12) and (13) are rotated at the same speed in opposite directions. Rotated with. The other parts of the grinding machine (1) can be configured in the same manner as a known vertical double-ended surface grinding machine.

The rotation device (2) is a work (wafer) (W)
The processing surfaces (a) and (b) on both sides of the work (W) face the upper and lower grinding surfaces (12a) and (13a), respectively. The work (W) is horizontally supported at the grinding position between the upper and lower grinding surfaces (12a) (13a) so that it is positioned inside the outer circumference of
(W) into and out of the grinding position, straddling between the front of the base (3) of the grinding machine (1) and the floor (A) in front of it. Base fixed as
(14). The base (14) includes left and right side plates (14a) (14b) that are vertical and long in the front-rear direction. Left and right side plates (1
The bases 14a and 14b are connected to each other at a lower portion so that the base 14 does not interfere with the grindstone heads 7 and 8 and the grindstones 12 and 13 and the like.

The rotation device (2) includes a left and right one extending in the front-rear direction.
A pair of endless drive belts (15) and (16), four guide rollers (17) and (18) rotating about a vertical axis, and a pair of right and left pressing rollers (19) rotating about a horizontal axis in the horizontal direction. ) (20).

A drive pulley (21), a driven pulley (22), and a tension pulley (23) are centered on a horizontal axis in the left-right direction on the inner surface in the left-right direction of each side plate (14a) (14b) of the base (14). The belts (15) and (16) are wound around these so that they can rotate. The belts (15) and (16) are, for example, rubber flat belts. Each drive pulley (21) is attached to each side plate (14a) (14b)
In the upper rear portion, each driven pulley (22) is disposed in the upper front portion of each of the side plates (14a) (14b), and each tension pulley (23) is disposed below the middle in the front-rear direction. The portion of the belt (15) (16) between the drive pulley (21) and the driven pulley (22) extends substantially horizontally in the front-rear direction, and this portion contacts the workpiece (W) with its upward surface. Work support (15a) (16
a). A substantially horizontal guide member (24) for receiving and guiding the work supporting portions (15a) (16a) of each belt (15) (16) from below is provided on the inner surface in the left-right direction of each side plate (14a) (14b). Fixed. Each drive pulley (21) is connected to an electric motor (2
The driving direction of each of the belts (15) and (16) can be independently switched by controlling the rotation direction of each motor (25). For each of the belts (15) and (16), the driving direction in which the work supporting portions (15a) and (16a) are moved to the rear side is the loading direction, and the driving direction in which the work supporting portions (15a) and (16a) are moved to the front side is The state where both belts (15) and (16) are driven in the carry-in direction is the work carry-in state, and the state where both belts (15) and (16) are driven in the carry-out direction is the work carry-out state. A state in which one of the belts (15) and (16) is driven in the carry-in direction and the other is driven in the carry-out direction is referred to as a work rotation state.

The guide rollers (17) and (18) are arranged symmetrically at two positions before and after the rear portion of the base (14), and two rear guide rollers are fixed guide rollers (17). , The front two are movable guide rollers (18). Each side plate (14a) (14b)
A support member that protrudes horizontally in the left-right direction at the upper front end
(26) are fixed, and fixed guide rollers (1
7) is rotatably mounted. Each fixed guide roller
(17) is the work supporting portion (15a) of the corresponding belt (15) (16)
(16a), and the upper surfaces of the work supporting portions (15a) (16a) are located at an intermediate portion of the height of the outer periphery of the fixed guide roller (14). Between the portions of the left and right side plates (14a) (14b) corresponding to the front portions of the belts (15) (16), a gate-shaped frame (27) is fixed. An electric motor (28) arranged downward at the center in the left-right direction of the horizontal part at the top of the frame (27)
The lower end is fixed in a penetrating manner, and a vertical feed screw (29) driven by a motor (28) is connected to a vertical feed screw (29) via a nut (30).
(31) is suspended. The elevating member (31) has a horizontal plate shape, and its left and right sides are guided by vertical portions on both sides of the frame (27) so as not to rotate around a vertical axis. By driving the motor (28), the elevating member (31) moves up and down a predetermined range. A support member (32) extending vertically downward is fixed to the left-right symmetrical position of the front part of the lifting member (31), and each support member (32)
A movable guide roller (18) is rotatably attached to the lower end of the. At the rear left and right symmetrical position of the elevating member (31), each cylindrical guide member (33) extending vertically downward and opening at the lower part is fixed, and a vertical rectangular cylindrical support member (34) opening at the upper part is fixed. ) Is slidably fitted on the guide cylinder (33). The support member (34) can move up and down a predetermined range along the guide member (33), and press rollers (19) and (20) are rotatably attached to the lower end thereof. A compression coil spring (35) as an elastic member for urging the support member (34) and the pressing rollers (19) and (20) downward in the hollow portions of the guide member (33) and the support member (34). Is provided. As shown in FIG. 3, when the elevating member (31) is lowered to the lower end position, the movable guide roller (18) and the pressing rollers (19), (20) are lowered to the operating position at the lower end. Belt (15)
The upper surface of the work supporting portions (15a) and (16a) of (16) is located at the middle of the height of the outer periphery of the movable guide roller (19) in the operating position. In addition, the presser roller (19) (20)
The work support portions (15a) (16) of the belts (15) (16) received on the upper surface of the front portion of the guide member (24) by the elastic force of the spring (35)
Press against the top surface of a). When the lifting member (31) is raised to the upper end position, the movable guide roller (18) and the pressing roller
(19) (20) is raised to the standby position at the upper end. Roller (1
9) The bottom part of (20) is the work support part of the belt (15).
(15a) It is considerably separated from the upper surface of (16a).

Front of belts (15) and (16), fixed guide rollers
(17) and the press rollers (19) and (20) are located near the grindstones (12) and (13), but are spaced at appropriate intervals on the left and right so as not to interfere with the grindstones (12) and (13). Are located.

The four guide rollers (17) and (18) constitute a radial support means for regulating the radial position of the work (W), and the left and right belts (15) and (16) and the pressing rollers (19). The axial support means for regulating the position of the work (W) in the axial direction and rotating the work (W) is constituted by (20).

In the case of this embodiment, the outer diameter of the grindstones (12) and (13) is about 70% of the outer diameter of the work (W), and the center (c) of the work (W) is at the time of the grinding operation described later. It is located slightly inside (right side) from the outer circumference of the grinding surfaces (12a) (13a).

Although the detailed illustration is omitted, the grinding device includes:
For example, a work carry-in / carry-out device provided with a carry-in / carry-in conveyor (36) or the like is provided.

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

During the grinding operation, the upper and lower grinding wheels (12, 13) are constantly rotating. At the start of the work, the upper and lower whetstones (12) and (13) move up and down to the standby position, and the movable guide roller (18) and the press rollers (19) and (20) rise to the standby position at the upper end.
The left and right belts (15) and (16) are stopped. In such a state, the work (W) is moved rearward by the conveyor (36), and is carried into the front portions of the work supporting portions (15a) (16a) of the belts (15) and (16). When the workpiece (W) is carried in, it is detected by an appropriate sensor (not shown) or the like, and the conveyor (3)
6) stops, the left and right belts (15) and (16) are driven in the loading direction, and the workpiece is loaded, the workpiece (W) is placed on the workpiece supporters (15a) and (16a), and the It is moved to. When the work (W) moves to the grinding position,
The portion comes into contact with the fixed guide roller (17), and the work (W) stops at that position. Work (W) is fixed guide roller (17)
, Is detected by a suitable sensor (not shown) or the like, and the belts (15) and (16) stop. Belt (15)
When (16) stops, the movable guide roller (18) and the holding rollers (19) and (20) are lowered to the lowermost operating position. As a result, the movable guide roller (18) moves to the front side 2 of the work (W).
The work (W) which is in contact with or in the vicinity of the outer periphery of the place, and in which the holding rollers (19) (20) are placed on the work supporting portions (15a) (16a) of the belts (15) (16) The workpiece (W) is supported in the radial and axial directions at the grinding position by pressing against the upper processing surface (a). Work (W) is
When supported at the grinding position, as shown in FIG. 2, the center (c) of the work (W) is located slightly behind (inside) the outermost foreground of the grinding surfaces (12a) (12b). .

The movable guide roller (18) and the holding roller (1)
9) If (20) is lowered to the operating position, the left and right belts (1
5) Steps (16) are driven in the opposite directions to each other, and the workpiece is rotated. When the left and right belts (15) and (16) are driven in opposite directions, the work supporting portions (15a) and (16a) of the belts (15) and (16) move in opposite directions with respect to the front-rear direction. The left and right sides of (W) are driven in the same direction in the circumferential direction by the frictional force with the belts (15) and (16), and the work (W) is substantially centered at its center (c) at the grinding position. Be rotated.

When the work (W) starts rotating, the grinding wheel (12)
(13) are moved in the direction approaching each other, and the ground surface (12
a) (13a) is brought into contact with the corresponding processing surfaces (a) and (b). As a result, the rear part of the work (W) is sandwiched between the grindstones (12) and (13), and a part of the rear outer periphery of the work (W) and the center (c) are ground surfaces (12a) (13a). ) Is located inside the outer circumference. Whetstone (12) (13)
Is moved to a predetermined position determined by the finished dimension of the work (W), and stopped at that position for a predetermined time.
In the meantime, the grinding surface of the workpiece (W) in contact with the ground surfaces (12a) (13a) by rotating the grinding wheels (12) (13)
(a) and (b) are ground and the work (W) is partially and
(c) is rotated inside the outer circumference of the grinding surfaces (12a) and (13a), so that the workpiece (W) rotates once.
The entire surface of the work surface (a) (b) of the work (W) passes between the grinding surfaces (12a) and (13a) and comes into contact with the grinding surfaces (12a) and (13a).
While the work (W) rotates several times, the entire surfaces of the processing surfaces (a) and (b) on both surfaces are simultaneously ground.

When the grinding of the work (W) is completed, the grinding wheel (12)
(13) moves away from the workpiece (W) and further moves to the upper and lower standby positions. When the grindstones (12) and (13) move away from the work (W), the belts (15) and (16) stop, thereby stopping the rotation of the work (W). When the work (W) stops, the movable guide roller (18) and the holding rollers (19) and (20) move up to the standby position, and the left and right belts (15) and (16) are driven in the unloading direction, so that the work is unloaded. become. As a result, the work (W) is placed on the work supporting portions (15a) (16a) and moved to the front side,
Transferred to conveyor (36). When the work (W) is transferred to the conveyor (36), the belts (15) and (16) stop, the conveyor (36) is driven forward, and the work (W) is carried out to the front side. When the work (W) that has been processed in this way is carried out, the next work (W) is carried in by the conveyor (36) as described above, and thereafter, the above operation is repeated to successively grind. Is performed.

If necessary, the entire base (14) can be moved in the front-rear direction so that the base (14) can be moved during grinding.
Is reciprocated in the front-rear direction.
Is reciprocated in the front-rear direction, that is, in the direction parallel to the grinding surfaces (12a) (13a) and connecting the center (c) of the work (W) and the axes of the grindstones (12) and (13). In this reciprocating movement, a part of the outer periphery on the rear side of the work (W) and the center (c) are always ground surfaces (12a) (13a).
Is performed within the range located inside the outer circumference of. For example,
The reciprocating stroke is about 5 mm. By reciprocating the work (W) in this way, the work
The flatness and surface roughness of the central portion of (W) can be improved.

When the work (W) is reciprocated during grinding, the direction of the reciprocation is determined by the center of the work (W) as described above.
A direction connecting (c) to the axis of the grindstones (12) and (13) or a direction close to this is desirable, but it may be reciprocated in another direction parallel to the grinding surfaces (12a) and (13a).

The upper and lower grindstones (12) and (13) are normally rotated at the same speed as in the above embodiment, but for example, it is desired to change the grinding allowance distribution of the upper and lower processing surfaces (a) and (b). In some cases, for example, the grinding speed can be changed by changing the rotation speed of the upper and lower grinding wheels (12) and (13). Also, the upper and lower whetstones (12) (1
It is also possible to grind by rotating 3) in the same direction.

In the first embodiment, a fixed guide roller
(17) requires at least two workpieces (W) moved by the belts (15) and (16) to reliably stop the workpiece (W) at the grinding position. Since the position of the workpiece (W) in the radial direction is regulated by the roller (17), it is sufficient that the number of the workpiece (W) is one or more.

In the first embodiment, the work (W) is carried out and carried in and out of the belts (15) and (16) by the conveyor (36). The work (W) is loaded directly into the front of the work supporting parts (15a) (16a) of the belts (15) and (16) using a simple work loading / unloading device, and the work (W) is directly unloaded from this part. You may make it.

In the first embodiment, the drive belt (15)
(16) The rear end is set to the grinding position, the work (W) is moved to the rear side, and is carried into the grinding position, and the work (W) is moved to the front side to be unloaded from the grinding position. However, for example, a work belt is carried into the grinding position from the left side by a drive belt extending on the left and right sides of the grinding position,
The workpiece after grinding can be carried out to the right from the grinding position. In this way, the belt can be driven in one direction to carry in and carry out the work. However, in this case, the guide roller corresponding to the fixed guide roller (17) of the above embodiment is also allowed to move up and down,
It is necessary to raise the guide roller to the upper standby position when unloading the work.

Further, in the first embodiment, the belts (15) (1)
The work (W) is carried in and out according to (6), but the belts (15) and (16) may be those that only rotate the work (W). In this case, the belts (15) and (16) may be short enough to support the work (W) at the grinding position. In addition, the positions of the guide rollers (17) and (18) are all fixed, and only the holding rollers (19) and (20) can be retracted to an appropriate position, for example, by a suitable work carrying-in / out means having a suction plate or the like. , Work (W) guide roller (17)
The belts (15) and (16) between (18) may be directly carried into the work supporting portions (15a) and (16a), and may be directly carried out from this position.

Although the flat belts are used in the first embodiment as the drive belts (15) and (16), other types of belts such as a timing belt may be used.

FIG. 4 shows the second embodiment, in which only the main parts corresponding to FIG. 2 of the first embodiment are shown.

The second embodiment is directed to a work (W) on which a flat portion (f) for positioning is formed, and the number of movable guide rollers (18) and (37) is equal to that of the first embodiment. Is different. That is, in the case of the second embodiment, auxiliary movable guide rollers (37) are provided slightly behind the two movable guide rollers (18), which are the same as in the first embodiment. The circumferential distance between the movable guide roller (18) and the movable guide roller (37) is slightly larger than the circumferential dimension of the flat portion (f).
The movable guide roller (37) is a movable guide roller (18).
And the same as the movable guide roller (18).

According to the second embodiment, the flat portion (f)
A certain work (W) can be surely supported in the radial direction by six guide rollers (17), (18) and (37) and can be rotated. However, this embodiment can, of course, be used for grinding a workpiece having no flat portion for positioning.

The specific configuration of the grinding device according to the second embodiment can be the same as that of the first embodiment. In FIG. 4, the same parts as those in the first embodiment are denoted by the same reference numerals.

In the above-described embodiment, the double-side grinding apparatus having a vertical axis with the axis of the grinding wheel being vertical has been described, but a horizontal axis with the axis of the grinding wheel being horizontal may be used. In this case, the work supporting portion of the drive belt is located in a vertical plane parallel to the vertical grinding surface of the grinding wheel on the horizontal axis, and the drive direction is vertical, horizontal, or an oblique direction between them. Either may be used.

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

[Brief description of the drawings]

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

FIG. 2 is an enlarged horizontal cross-sectional view showing a main part of the workpiece rotation device of FIG. 1;

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

FIG. 4 is a schematic configuration diagram illustrating a main part of a workpiece rotation device according to a second embodiment of the present invention.

[Explanation of symbols]

 (2) Work rotation device (work rotation means) (12) (13) Grinding wheel (12a) (13a) Grinding surface (15) (16) Drive belt (15a) (16a) Work support (17) Fixed guide roller (18) Movable guide roller (19) (20) Holding roller (37) Movable guide roller (W) Work (semiconductor wafer) (a) (b) Work surface (c) Center

Claims (4)

[Claims] 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 supported at a grinding position between the grinding surfaces so that the grinding surfaces of the pair of grinding wheels are respectively opposed to each other and a part and a center of the outer periphery of the work are located inside the outer periphery of the grinding surface. Work rotation means for rotating the work, the work rotation means, the radial support means for regulating the radial position of the work,
Axial support means for regulating the position of the work in the axial direction, wherein the radial support means rotates in contact with the outer periphery of the work that is out of between the grinding wheels A pair of drive belts, comprising a guide roller, wherein the axial support means contacts and moves at two places on the processing surface of the work that is out of the space between the grinding wheels and rotates the work. A press roller for pressing the work between the drive belt and the work surface of the work from the opposite side so that the work is sandwiched between the drive belts. apparatus. 2. A pair of drive belts are arranged in parallel with each other such that a surface of a work supporting portion that comes into contact with the work is directed upward, and a driving state of the pair of drive rollers is controlled by the work supporting portion. Are moved in the same carry-in direction to each other and carry the work placed thereon to the grinding position, and the work supporting portion moves in the same carry-out direction to carry the work placed thereon. The state in which the work is unloaded from the processing position and the state in which the work supporting portion moves in the opposite direction to rotate the work placed on the workpiece in a rotating direction are switched to each other. The workpiece is raised and lowered between a standby position separated from the upper workpiece and an operating position of pressing the workpiece on the drive belt. At least to stop it in contact with the outer periphery of the movement direction front portion of the workpiece which has been moved by the drive belt of the pair of over-click loading state 2
Fixed guide rollers, and at least one movable guide roller abutting on the outer periphery of a portion of the workpiece stopped in the movement direction, which is stopped by the fixed guide roller, wherein the movable guide roller is driven by 2. The thin plate circle according to claim 1, wherein the thin plate circle is moved up and down between a standby position on the belt above the work and a working position on the drive belt contacting the outer periphery of the work. Double-sided grinding machine for plate-like work. 3. The apparatus according to claim 2, wherein said work supporting portions of said pair of drive belts are guided by a guide member disposed therebelow. 4. The thin disk-shaped plate according to claim 2, wherein said pressing roller and said movable guide roller are mounted on the same elevating member so as to elevate and lower in synchronization with each other. Workpiece double-side grinding machine.