JPH11254307A - Thin board working device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve thickness accuracy of a workpiece by lapping two sides of the workpiece, reduce irregularity of thickness among the workpieces, and work a thin workpiece with high accuracy. SOLUTION: This device is a sheeting type single-side working device, which rotates a jig where one thin board is installed to a top of an oscillating arm, and a fixed abrasive grain surface plate respectively to work a surface of a board by lapping. This jig installs the board to a reference plane 13 of an suction means like a vacuum plate 14. A stopper in which an adjusting ring 11 made of a highly hard surface material 17 is provided at a lower end of an adjusting screw 16 with a compression spring 15 on a base plate 10 around the reference plane, wherein the stopper is held by three-point mechanism and sets a distance between the reference plane and the stopper, thickness of a workpiece, and parallelism to the reference plane freely.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a processing apparatus for processing upper and lower surfaces of a substrate made of ceramics, ferrite or the like into parallel flat surfaces.

[0002]

2. Description of the Related Art Generally, in parallel cutting of a substrate made of a brittle material such as ceramics or ferrite, both ends cut with a grindstone have poor parallelism or bend due to meandering of the grindstone and imbalance in cutting strain. Therefore, parts and substrates that require parallel or parallel surfaces at both ends have been subjected to simultaneous double-sided lapping after cutting both ends.

In this type of double-sided lapping method for a substrate, a substrate to be processed, that is, a workpiece is held on a carrier so that both surfaces thereof are exposed, and the carrier is sandwiched between an upper and lower platen. It is common to rotate and revolve, and to lap by contact sliding between the upper and lower platens and the workpiece.

FIG. 6 shows a configuration of a carrier 61 that rotates and revolves between the upper and lower stools.

In this case, (a) the carrier 61 is engaged with the internal gear 62 and the sun gear 63 without rotating the upper and lower platens as shown in FIG. Rotate the workpiece 64,
Or (2) the carrier 61 is rotated and revolved by the internal gear 62 and the sun gear 63, and the lower platen is rotated. There has been known a method called a so-called 4-way method in which both the upper and lower platens are rotated in the same direction or opposite directions while rotating and revolving.

[0006]

The conventional double-sided lapping method described above can be processed with a considerably high precision.
However, the workpiece is sandwiched between the upper surface plate and the lower surface plate, and further, free abrasive grains are used in the working fluid. Therefore, the abrasive grains always intervene between the workpiece and the surface plate, and cut the workpiece.

Here, since the working fluid containing the abrasive grains is constantly poured while the working apparatus is operating, the abrasive particle diameter in the working fluid is sequentially reduced and becomes smaller. In other words, since the abrasive grains in the newly poured working fluid and the abrasive grains in the remaining working fluid have different particle diameters, the processing accuracy of the workpiece becomes unstable.

[0008] Further, since the chips are mixed with the abrasive grains and the abrasive viscosities are different, the flow rate of the abrasive grains changes, which is one of the factors which degrade the accuracy of the substrate thickness.

Further, a plurality of carriers are loaded in the surface plate, and a plurality of workpieces are also loaded in the carrier. Here, if the substrate thickness before the lapping process is not uniform, the upper platen may be inclined. If the substrate is processed as it is, the processing accuracy of the workpiece becomes uneven, and the thickness of the substrate becomes uneven.

Further, since the workpiece is loaded on the carrier and processed, it is impossible in principle to process the workpiece to a thickness of the carrier or less. That is, it is not possible in principle to process a thin substrate.

Accordingly, the present invention improves the accuracy of the thickness of the workpiece, which is a problem with the above-described double-sided lapping method, and further reduces the variation in the thickness between the workpieces. Still another object of the present invention is to provide a thin substrate processing apparatus capable of processing with high precision even if a workpiece is a thin substrate.

[0012]

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problems, and has the following features. (1) In a processing apparatus for processing a substrate surface and processing a thin substrate in which the upper and lower surfaces of the substrate are parallel with high precision, at least an oscillating arm and one substrate at the tip of the oscillating arm are used. A jig to be individually mounted, comprising a fixed abrasive platen, a thin substrate processing apparatus for processing the surface of the substrate by processing by rotating the jig and the fixed abrasive platen, respectively,
The jig comprises at least a reference surface on which a substrate is mounted, a connection portion connected to the swing arm, and a stopper portion provided with a high-hardness material in a part thereof and disposed around the reference surface. Provides a thin substrate processing apparatus having a jig held by a three-point support mechanism.

(2) The stopper portion is disposed at an arbitrary height from a reference plane, and a function of restricting a processing width by a high-hard material disposed on a part of the stopper portion coming into contact with the surface plate. The thin substrate processing apparatus according to (1), further comprising a jig having the following.

(3) The support portion of the three-point support mechanism for holding the stopper portion is provided with a threaded adjusting screw, and the height, inclination and position of the stopper portion are arbitrarily adjusted by the adjusting screw. A thin substrate processing apparatus according to (1) or (2), further comprising a jig capable of performing the processing.

(4) The thin substrate processing apparatus according to any one of (1) to (3), further comprising a jig in which an elastic sheet is attached to a reference surface on which the substrate is mounted.

[0016]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention employs a so-called single-wafer method in which workpieces are processed one by one in order to further reduce in-plane variation and inter-plane variation which are problems in double-sided lapping. Attach a workpiece and process it on one side.

The jig is provided with a stopper having a uniform distance from the reference surface and having a high-hardness material as a part of the jig around the workpiece mounting portion on the reference surface. Even if the workpiece is attached to the jig and the workpiece is processed, the thickness of the workpiece does not become less than the distance between the high-hardness material and the reference surface, and the workpiece has a constant thickness. Adjusted. Furthermore, if the reference surface is adjusted to be accurately parallel to the surface plate, the workpiece can be processed in parallel plane processing with high accuracy. The stopper of the jig is held by a three-point support mechanism, and the distance between the reference surface and the stopper can be freely set. Therefore, the adjusting screws provided on the three supports are operated. By doing so, the reference plane can be changed, so that the thickness of the workpiece, the parallelism with the reference plane, and the like can be freely set.

Accordingly, the thickness of the workpiece can be freely set, and a thin substrate or the like can be processed with high precision.

Further, a sheet made of an elastic material is adhered to the reference surface on which the workpiece is to be attached. Even if a small amount of dust, chips or the like is attached to the reference surface, the dust is absorbed by the elastic material and high Precise parallelism flatness is not impaired.

Further, the surface plate used in the processing apparatus according to the present invention uses a fixed abrasive particle surface plate of diamond, and is concerned with a change in abrasive particle diameter, mixing of chips, a change in abrasive particle flow, and the like. This is to correct the unevenness of the thickness of the workpiece.

[0021]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of a thin substrate processing machine according to the present invention will be described below with reference to the drawings.

FIGS. 1 and 2 show the overall structure of the embodiment. In this embodiment, the substrate is used as the workpiece, but the workpiece is not limited to the substrate.

In these figures, as disclosed in Japanese Utility Model Publication No. 07-048369, a thin substrate processing apparatus according to the present invention has at least one fixed abrasive platen 2 for polishing. (Three in the figure) are placed,
A swing mechanism having a swing arm 3 is provided for each surface plate 2. As shown in FIG. 2, spindles 5 are respectively installed on the main body table 1 to rotationally drive the individual platens 2, and each spindle 5 is rotationally driven by a spindle motor 6. Surface plate 2 is spindle 5
The upper part is fixed to a spindle table 7 integrated therewith. A jig 8 is attached to the tip of the swing arm 3 to attach a substrate, which is a workpiece, to the polishing surface of the upper surface of the platen.

FIG. 3 shows a configuration diagram of the jig 8.

The jig 8 is composed of a base plate 10 and an adjustment ring 11 centering on a rotating shaft 9. The base plate 10 includes a vacuum plate 14 having a reference surface 13 for fixing a substrate 12 to the jig 8. A compression spring 15 for pulling the adjusting ring 11 toward the base plate 10 and an adjusting screw 16 are attached. Here, the vacuum plate 14 is provided with a suction mechanism, and has a structure in which the substrate 12 is fixed to the reference surface 13 by suction.

The adjusting ring 11 is provided with a hard material 17 on the surface of the upper surface of the platen which is in contact with the polished surface, and adjusts the thickness and surface of the substrate. That is, when the substrate 12 is mounted on the jig 8 of the processing apparatus according to the present invention, the substrate 8 comes into contact with the polished surface of the surface plate immediately after the processing is started, but the substrate has a predetermined thickness. At this time, the polished surface of the surface plate comes into contact with the high hard material 17 arranged on the adjustment ring 11. When the hard material 17 comes into contact with the polished surface of the surface plate, the substrate 12 is no longer processed. Therefore, by adjusting the adjustment ring 11 to adjust the positional relationship between the hard material 17 and the substrate 12,
The parallelism and flatness of the second surface can be processed with high accuracy, and even a thin substrate can be processed. Here, as the high-hardness material 17, any material can be used as long as it has a higher hardness than the substrate as the workpiece, but it is preferable to use sapphire.

In the thin substrate processing apparatus according to the present invention, since it is important to adjust the positional relationship between the adjustment ring 11 having the hard material 17 and the substrate 12 with high precision, the reference surface 13 of the jig 8 is made flat. It is necessary to keep. Therefore, it is required that the reference surface 13 be made of a material that has high rigidity, is hardly damaged, and has corrosion resistance. For example, SUS
Preferably, a material having a coating on the surface thereof, a porous ceramic or the like is used.

However, the substrate to be processed is about 17 substrates.
Submicron processing accuracy is required because it may be as thin as 0 μm, and it is easily affected by a small amount of dust, chips or abrasive grains. May be impaired.

FIG. 4A shows a case where the substrate is directly sucked on the reference surface, and FIGS. 4B and 4C show a case where the substrate is sucked on the reference surface on which the elastic body is attached. As shown in FIG.
When the substrate 12 is directly sucked to the substrate 3, foreign substances 19 such as dust and chips attached to the substrate surface are interposed between the reference surface 13 and the substrate 12, and the substrate 12 is chipped or cracked. The effect of such small foreign matter 19 becomes more remarkable as the substrate 12 becomes thinner.

Here, as shown in FIG. 4B, when an elastic body 18 having an appropriate thickness is stuck on the reference surface 13, small foreign matter 19 is absorbed in the elastic body 18 and the precision of the substrate is reduced. Can be kept at a high level.

Therefore, if the elastic body 18 is interposed between the reference surface 13 and the substrate 12 in order to absorb foreign matter 19 such as dust and chips, the foreign matter 19 attached to the reference surface is absorbed into the elastic body and becomes high. It is possible to obtain an accurate substrate, and it is possible to prevent deterioration in accuracy by protecting the reference surface.

However, if the thickness of the elastic body 18 is too large as shown in FIG. 4 (c), the elastic body 18 itself changes greatly with respect to the attraction force of the substrate 12, and the variation in the finished dimensions of the substrate becomes large. Becomes Therefore, it is preferable to use polypropylene for the elastic body 18 and the thickness is 0.03 mm.
To 0.06 mm is preferred.

The jig used in the thin substrate processing apparatus according to the present invention adjusts the positional relationship between the hard material and the substrate to set the thickness, parallelism, etc. of the substrate to an arbitrary value and with high accuracy. However, since the elastic body is attached to the reference surface, the reference surface may change slightly due to the suction of the substrate.Adjust the adjustment ring with the jig alone to adjust the reference surface. Can not do it.

Therefore, when adjusting the reference surface with the jig alone, the reference surface setting device is sucked to the reference surface of the jig, and the elastic body attached to the reference surface is brought into the same state as when the substrate is sucked. It is necessary to make adjustments after changing to. At this time, at least three dimension detectors provided on the reference plane setting tool are brought into contact with the high-hardness material on the adjustment ring, and the respective values are adjusted with the adjustment screws. The surface can be adjusted. Here, it is desirable to use an electric micrometer as the size detector.

The adjustment of the reference plane is not limited to the method described above, and an actuator may be used instead of the adjusting screw. The jig is mounted on the processing machine and the substrate is mounted. It may be adjusted. In this case, if an online monitor for thickness measurement is attached, high-precision automatic adjustment becomes possible.

FIG. 5 shows a configuration diagram of a thin substrate processing apparatus according to the present invention.

As shown in the drawing, the thin substrate processing apparatus according to the present invention mounts a plurality of substrates before processing on the magazine 20 and automatically takes out the substrates one by one by operating the swing arm 3. The jig 8 is suctioned after checking for chipping. The jig 8 is rotated by the swing arm 3 to the fixed abrasive platen, and the grinding fluid is caused to flow on the ground surface of the rotating fixed abrasive platen 3. Subsequently, the jig 8 is swung by the rotation and swing arm 3, and the processing is started.

The substrate that has been attracted to the jig 8 is processed in contact with the ground surface at the beginning of processing, but gradually comes into contact with a high-hard material on the adjustment ring provided in the jig 8 to process the substrate. Is no longer so good that the substrate has the set thickness.

To prevent clogging of the surface plate 2 with chips, dressing is performed by a brush containing abrasive grains during rotation of the surface plate, and reciprocates or rotates. When the processing is completed, the jig 8 is moved by the swing arm 3 to the substrate discharge position.
1 and the substrate is discharged by the compressed air.

Thereafter, the reference surface of the jig passes through a brush cleaning or roller cleaning 22 and a draining step 23 to remove chips and the like, and the processing of one substrate is completed. that's all,
By repeating this operation, a large number of substrates can be uniformly and continuously processed.

[0041]

According to the thin substrate processing apparatus of the present invention, a thin substrate processing which is difficult with the conventional processing apparatus can be performed, and the processing accuracy of the substrate is improved.

When 150 substrates / lot were processed by this processing apparatus, the in-plane variation was within 0.3 μm, the
= 0.06 µm, and the variation between the surfaces was also within 0.5 µm. Furthermore, the same accuracy was achieved even if the same processing was repeated several lots.

[Brief description of the drawings]

FIG. 1 is an external view of a thin substrate processing apparatus according to the present invention.

FIG. 2 is a side perspective view of the thin substrate processing apparatus according to the present invention.

FIG. 3 is a structural view of a jig used in the thin substrate processing apparatus according to the present invention.

FIG. 4 is a conceptual diagram showing a state during processing.

FIG. 5 is an official drawing of equipment according to the present invention.

FIG. 6 is a configuration diagram showing a carrier of a conventional double-sided lapping machine.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Main body table 2 Surface plate 3 Swing arm 8 Jig 10 Base plate 11 Adjustment ring 12 Substrate 13 Reference surface 14 Vacuum plate 15 Compression spring 16 Adjustment screw 17 High-hard material 18 Elastic body 19 Foreign matter such as dust and chips

Claims (4)

[Claims] 1. A processing apparatus for processing a substrate surface and processing a thin substrate whose upper and lower surfaces are parallel with high accuracy,
At least an oscillating arm, a jig at the tip of the oscillating arm for mounting one substrate, and a fixed abrasive platen,
A thin substrate processing apparatus for processing a surface of a substrate by a lapping method by rotating the jig and the fixed abrasive platen, respectively, wherein the jig is connected to at least a reference surface on which the substrate is mounted and the swing arm. And a stopper portion provided with a high-hardness material in a part thereof and disposed around the reference surface, wherein the stopper portion has a jig held by a three-point support mechanism. Substrate processing equipment. 2. The stopper portion is disposed at an arbitrary height from a reference plane, and has a function of restricting a processing width by a high-hard material disposed on a part of the stopper portion coming into contact with the surface plate. 2. The thin substrate processing apparatus according to claim 1, further comprising a jig. 3. A support portion of the three-point support mechanism for holding the stopper portion is provided with a threaded adjusting screw, and the height, inclination and position of the stopper portion are arbitrarily adjusted by the adjusting screw. The thin substrate processing apparatus according to claim 1, further comprising a jig capable of performing the processing. 4. The thin substrate processing apparatus according to claim 1, further comprising a jig having an elastic sheet attached to a reference surface on which the substrate is mounted.