JP3498902B2 - Semiconductor wafer flattening device - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a semiconductor wafer flattening apparatus for flattening the surface of a processed semiconductor wafer using a grindstone, and in particular, after forming an uneven pattern by fine processing on the wafer surface. The present invention relates to a technique for flattening unevenness on a wafer surface which occurs when an insulating film is coated.

[0002]

2. Description of the Related Art In recent years, with the increasing density and miniaturization of semiconductor devices, the lack of an optical focus margin in a pattern exposure process on a semiconductor wafer has become a problem, and it is extremely important to flatten the surface of the device wafer. That is, when an insulating film (resist film) is coated after forming a concavo-convex pattern on the surface of a semiconductor wafer by microfabrication, irregularities are generated on the surface of the semiconductor insulating film. Since the focal point is generated, it is necessary to flatten the wafer surface (insulating film surface) that has been subjected to the process processing of the uneven pattern as described above.

One of the wafer flattening techniques is a polishing method called chemical mechanical polishing (CMP), which is shown in FIG.

In FIG. 10, reference numeral 11 denotes a polishing pad, which is attached on a surface plate 12 having a rotating mechanism 16.
The polishing pad 11 is formed by, for example, slicing a foamed urethane resin into a thin sheet, and selecting various materials and a fine surface structure depending on the type of work piece and the degree of surface roughness to be finished. Can be used properly.

The semiconductor wafer 1 to be flattened is
Elastic sponge layer (also called insert) 13
It is held by the wafer holder 14 on the surface of the polishing pad 11 via.

The polishing pad 11 rotates together with the rotary platen 12, and the wafer holder 14 is placed on the rotating polishing pad 11.
Also applies a load to the wafer 1 rotating together with the wafer holder 14 while rotating independently, and in this manner, the wafer 1 rubs relative to the polishing pad 11, and further the polishing slurry 15 is rubbed on the polishing pad 11. By supplying, the convex portion of the insulating film on the surface of the wafer is removed by polishing and the surface is flattened.

When polishing an insulating film such as silicon dioxide, colloidal silica is generally used as a polishing slurry. Colloidal silica is obtained by suspending fine silica particles having a diameter of about 30 nm in an alkaline aqueous solution such as potassium hydroxide.
Compared with mechanical polishing using only abrasive grains, it has a feature that a dramatically higher processing efficiency and a smooth surface with less processing damage can be obtained.

The method of processing while supplying the polishing slurry between the polishing pad and the work piece is widely known as a free abrasive grain polishing method, but it is sufficiently flat depending on the type of pattern and the state of steps. There is a pattern dimension dependency that it cannot be realized, and the cost of consumables such as polishing slurry and polishing pad tends to be extremely high. Further, there are problems such as lack of long-term stability due to wear of the polishing pad.

As an alternative to such a flattening technique by free abrasive grain polishing, a flattening technique by a fixed abrasive grain polishing method has become possible in recent years as disclosed in PCT / JP95 / 01814.

This new flattening technique is characterized by using a special grindstone whose hardness is optimally controlled, in place of the conventional polishing pad or polishing slurry, whereby high precision is achieved. It is possible to realize the polishing processing of the semiconductor wafer, which requires the flattening technology.

Specifically, the elastic modulus of the grindstone is 5 to 500 k.
g / mm ² , which is 1/10 to 1/100 in hardness as compared with conventional general grindstones, and conversely, hard polishing such as hard foamed polyurethane used in the above free abrasive polishing method. It is 5 to 50 times harder than the pad.

Abrasive grains such as silicon dioxide, cerium oxide, and aluminum oxide are preferable as the type of abrasive grains. These abrasive grains are kneaded with a binding resin, solidified by applying an appropriate pressure, and heat-cured as necessary. A grindstone is formed by adding such treatments. In the above manufacturing method, the type of binder resin,
Also, the hardness of the resulting grindstone can be controlled by the pressurizing pressure, and in the present technology, the hardness is set to 5 to 500 kg / mm ² . If the grain size of the abrasive grains is about 0.01 to 1 μm, good working efficiency can be obtained without causing scratches. A high-purity organic resin such as a phenol-based resin, an epoxy-based resin, a melamine-based resin, a urethane-based resin, or a polyester-based resin is preferable as the resin for bonding these abrasive grains.

For example, pure water is supplied as a polishing liquid to a whetstone produced by bonding cerium oxide abrasive grains having a particle diameter of 1 μm with a phenolic or polyester resin so as to have an elastic modulus of 100 kg / mm ^2. When a silicon dioxide film with a thickness of 1 μm is flattened (polished) by using, no scratches are generated, and the processing speed is 0 for all types of patterns with a pattern width of 10 mm to 0.5 μm. Very good flattening performance of within 0.3 ± 0.01 μm / min is obtained. The compatibility between the scratch-free processing and the good flattening performance is an effect that can be achieved for the first time by the fixed abrasive processing using a grindstone with an optimized elastic modulus.

In the conventional free abrasive grain processing, the wafer 50 is used.
Although the polishing pad reaches the end of its life with about 0 wafers, the fixed-abrasive polishing technique allows the thickness of the grindstone to be several cm, so the life of the grindstone can be extended to about 15,000 wafers processed. . This means that the frequency of exchanging the polishing pad can be reduced to 1/30 from once a day to once a month, which is a great advantage at the mass production site. Incidentally, in the prior art, as in the flat polishing apparatus described in JP-A-60-242975, as a grindstone, for example, a granular material such as silicon carbide, aluminum oxide, chrome oxide, or cerium oxide is used as an abrasive grain. It has been proposed to use abrasive grains dispersed in a porous body containing a polyvinyl acetal-based synthetic resin as a main component and blended, but the flat processing (polishing) target is, for example, metal, glass, or synthetic material. It is a resin or the like. The flattening of the semiconductor wafer requires higher precision polishing than the above-mentioned metal, glass, and synthetic resin, and it is not enough to bond the above-mentioned abrasive grain material with resin.
Securing the optimized elastic modulus disclosed in JP95 / 01814 is an essential condition.

[0015]

In the fixed abrasive polishing method in which the elastic modulus of the grindstone is optimized for wafer processing as described above, the unevenness of the insulating film produced by the process processing of the wafer is polished and flattened. However, the surface plate required for flattening usually has an outer diameter of about 700 mm or more and a weight of about 100 kg or more. In addition, the grindstone replacement work must be performed in a narrow space inside the device. In addition, since this type of device is often installed in a clean room, it is necessary to replace the grindstone in a short time without affecting the surrounding environment. Therefore, regarding the grindstone,
If this point is not taken into consideration, handling will be extremely difficult.

In order to deal with such a problem, it is a good idea to divide the grindstone into segments. Segmentation of the grindstone is disclosed, for example, in the above-mentioned prior art (Japanese Patent Laid-Open No. 60-242975). That is, by the segmented grindstone, if the grindstone can be partially replaced, the handling is simple,
Further, even if a part of the grindstone is damaged, it is not necessary to replace the whole grindstone, which is advantageous in cost.

However, when the grindstone used in the flattening apparatus for the semiconductor wafer is segmented, the following problems peculiar to the wafer remain.

When a semiconductor wafer is flattened by using a grindstone, the required flattening accuracy is extremely higher than that of other objects to be processed (for example, metal, glass, plastic, etc.). Must be prevented as much as possible, and the segmented grindstones are required to have flat surfaces and have a uniform height, that is, so-called highly accurate surfacing.

A first object of the present invention is a wafer flattening apparatus capable of achieving both segmentation of a grindstone for a semiconductor wafer, which requires highly precise surface flattening, and prevention of minute chipping of the segmented grindstone. (Polishing device).

A second object of the present invention is to provide a wafer flattening apparatus which improves the surface precision of segmented grindstones.

A third object of the present invention is to provide a wafer flattening device which prevents lateral displacement of a grindstone even by sliding friction between a wafer and a segmented grindstone and which always realizes highly accurate flattening of a semiconductor in an appropriate grindstone arrangement. To provide.

[0022]

According to a first aspect of the present invention, a surface plate having a rotating mechanism and a grindstone mounted on the surface plate are provided, and a surface of a semiconductor wafer subjected to a process treatment is formed by using the grindstone. In a flattening apparatus for a semiconductor wafer to be flattened, the grindstone is a grindstone of a fixed-abrasive polishing method that contains abrasive grains and a substance that binds and holds these abrasive grains, and is divided into a plurality of segments. It is adhered to a divided grindstone base, and is replaceably mounted on the surface plate in a divided unit of the grindstone base via the grindstone base, and the gap between the segments of the grindstone is set to 0.2 to 2 mm. It is characterized by being

According to the above construction, in addition to the advantages of segmenting the grindstone such as easy handling such as exchanging the grindstone, the gap between the segments of the grindstone is set to 0.2 to 2 mm. It is possible to effectively prevent the occurrence of chipping at the edge (side edge) (details will be described in the embodiment section of the invention).

According to a second aspect of the invention, similarly to the above, the grindstone in the semiconductor wafer flattening device is a grindstone of the fixed abrasive polishing method, and is divided into a plurality of segments, which are adhered to the similarly divided grindstone base. It is replaceably attached to the surface plate in a divided unit of the grindstone base via the grindstone base, and the segment of the grindstone is surface-adsorbed to the surface plate via each divided grindstone base. Characterize.
The surface attraction is performed by, for example, vacuum attraction, magnetic attraction, a combination of the vacuum attraction and the clamp mechanism, or a combination of the magnetic attraction and the clamp mechanism. It is possible to omit the use of bolts for mounting the wheel segment.

According to this structure, for example, even if the grindstone base to which the segmented grindstone is adhered has a distortion or a warp, the grindstone base is surface-adsorbed on the surface plate, so that the grindstone base is distorted or warped. Is forcibly fixed. Therefore, the whetstone held on the whetstone base does not partly float from the surface plate, and the chamfering process for matching the height of each surface of the segment with the whetstone segment firmly attached to the surface plate surface ( Dressing) can be carried out, ensuring a highly accurate surfacing of the wheel segment.

According to a third aspect of the present invention, similarly to the above, the grindstone in the semiconductor wafer flattening apparatus is a grindstone of the fixed-abrasive polishing method, divided into a plurality of segments, and similarly bonded to the divided grindstone base. Through the grindstone base, the grindstone base is replaceably mounted on the surface plate in a divided unit, and on the surface plate, the sliding frictional force due to the flattening process of the semiconductor wafer is divided into the respective grindstones. A plurality of keys are arranged so as to be locked and received by the base.

According to this structure, even if a strong sliding frictional force is generated between the wafer and the grindstone due to the flattening process of the semiconductor wafer, this sliding frictional force is arranged on the surface plate through the grindstone base. It is possible to prevent lateral deviation of the segmented whetstone that is received by the key.

[0028]

Embodiments of the present invention will be described with reference to the drawings.

FIG. 1 is a perspective view showing a main part of a semiconductor wafer flattening apparatus according to an embodiment of the present invention, and a partially enlarged view of a portion A thereof. FIG. 2 is a rotation constant of the flattening apparatus. FIG. 3 to FIG. 7 are perspective views showing an arrangement state of the grindstone segments on the surface plate by partially removing the grindstone segments on the surface plate, and FIGS. 3 to 7 are examples of various aspects of a mechanism for mounting the grindstone segments on the surface plate. FIG. 2 is a vertical sectional view corresponding to the line BB ′ in FIG. 1. Note that the same or common portions are denoted by the same reference symbols between the drawings.

In FIG. 1, the disk-shaped surface plate 12 has a diameter of, for example, about 700 mm and has a rotating mechanism similar to that shown by reference numeral 16 in FIG.

On the surface plate 12, a grindstone segment 20 is similarly divided into plural pieces through a grindstone base 51 divided into a plurality of pieces (here, 12 pieces are illustrated).

The grindstone segment 20 is prepared by kneading abrasive grains such as silicon dioxide, cerium oxide, and aluminum oxide with a binding resin, for example, a high-purity organic resin such as phenol-based, epoxy-based, melamine-based, urethane-based, or polyester-based resin. It is solidified by applying appropriate pressure, and if necessary heat-cured, etc., the elastic modulus is 5 to 500 kg.
/ Mm is the ² to become as.

The grindstone segment 20 is adhered onto the grindstone base 51, and the surface plate 1 is divided into units of the divided grindstone base 51.
It is attached to 2 in a replaceable manner. That is, the grindstone base 51 and the grindstone segment 20 that have been divided constitute a replaceable segment unit 50. The gap between the segments 20 is set in the range of 0.2 to 2 mm.

The grindstone segment 20 is surface-sucked to the surface plate 12 through the divided grindstone bases 51. Here, a specific example of the suction mechanism of the grindstone segment 20 is shown in FIG.
Will be explained.

In FIG. 3, a plurality of grooves 25 for vacuum suction are provided on the surface of the surface plate 12 in line with the arrangement of the segment units 50 to be suctioned. The groove 25 has a depth of several millimeters and communicates with a vacuum passage 25A provided in the surface plate 12. One end 25A 'of the vacuum passage 25A is located on the lower surface of the surface plate 12 and is connected to a vacuum pump (not shown).

When each segment unit 50 is mounted on the surface plate 12, by abutting the outer periphery of a polygonal (decagonal) convex portion (center indexing plate) 27 fixedly arranged in the center of the surface plate 12, The radial positioning on the surface plate 12 is performed. The outer circumference of the convex portion 27 and the side edge on the inner diameter side of the grindstone base 51 are engaged with each other via the convex portions and concave portions 27A and 51A to prevent the segment unit 50 from rising.

When the segment unit 50 is placed on the surface plate 12 while keeping a predetermined space, and a vacuum is sucked by a pump, the inside of the vacuum suction groove 25 is in a vacuum state, and the grindstone segment 20 is attached to the surface plate 12 via the grindstone base 51. It is vacuum-adsorbed on the surface. The larger the surface area of the vacuum suction groove 25, the stronger the suction force.

As shown in FIG. 1, with the grindstone segment 20 adsorbed, the semiconductor wafer 1 held by the wafer holder 14 having a rotating mechanism is pressed onto the grindstone segment 20. By rotating the grinding wheel segment 20 group together with the surface plate 12 and rotating the semiconductor wafer 1 together with the wafer holder 14 separately, the wafer 1 relatively slides on the grinding wheel segment 20, and the surface of the semiconductor wafer 1 is Flattened. The polishing pressure required for flattening is 100 to 400 g / cm ² . Pure water is used as a polishing liquid for cooling.

According to the above embodiment, the following actions and effects are obtained.

(1) First, by segmenting the grindstone, the handling such as exchanging the grindstone is simple and advantageous in terms of cost.

(2) The gap between the grindstone segments is 0.2
By setting it to ˜2 mm, it is possible to effectively prevent the occurrence of chipping on the side edge of the grindstone. Here, the mechanism in which the grinding wheel side edge is chipped will be described with reference to FIG.

FIG. 11A is a view of the relationship between the grindstone segment 20 and the semiconductor wafer 1 when the wafer is flattened, as seen from above. The arrow a indicates the rotation direction of the surface plate and the grindstone segment 20, and the arrow b. Indicates the rotation direction of the wafer 1 rotated by the wafer holder. Although the wafer 1 is rotating at a specific place as shown by the solid line, the grindstone segment 20
With respect to the relationship with, the relative movement in the direction of the arrow c, so one of the loci of the relative movement is equivalently shown by a broken line.

FIG. 11B shows a state of relative movement of the wafer 1 seen from the grindstone segment 20, showing a state in which a part of the peripheral edge of the wafer 1 is about to pass through the gap 21 between the segments 20. ing. Since a polishing pressure is applied to the wafer 1, a load W is applied, and when the gap 21 becomes large, the bending deformation force acting on the wafer 1 due to the load W becomes large, whereby the edge of the grindstone segment 20 (the portion shown by diagonal lines). May be chipped. According to the trial of the present inventors, in order to prevent such chipping, it is preferable that the gap between the segments of the grindstone is 2 mm or less, and if it is 0.2 mm or less, the polishing liquid (cooling water) is It was found that the dimensional change of the segment due to the swelling when the grindstone segment 20 is sucked in cannot be sufficiently absorbed. Therefore, the gap 21 between the segments should be 0.2 to 2
mm. Also, the optimum value of the gap 21 is 0.5 mm.
To propose.

(3) The grindstone segment 20 is mounted on the surface plate 12 and is faced by dressing so that the heights of the surfaces of the respective segments are matched with each other. According to this embodiment, the grindstone base 20 is used. Even if the 51 is originally distorted or warped, a highly accurate surfacing is guaranteed. That is, even if the grindstone base 51 is distorted or warped,
The surface of the grindstone base 51 is forcibly adsorbed onto the surface of the grindstone base 2 through a vacuum mechanism, so that the distortion and warpage of the grindstone base 51 are forcibly corrected. Therefore, the whetstone 20 held by the whetstone base 51 does not partly float from the surface plate, and the surface of the surface of the segment is made to match with each other while the whetstone segment is firmly attached to the surface plate surface. Processing (dressing) can be performed. As a result, a highly accurate surfacing of the grinding wheel segment is guaranteed.

(4) By removing the vacuum suction, the grindstone segment 20 can be easily attached / detached or replaced in a short time, so that the influence on the clean room can be minimized.

FIG. 4 shows another mode of the mechanism for mounting the segment unit 50 (the grindstone segment 20, the grindstone base 51) on the surface plate 12.

This example is an example in which the segment unit 50 is mounted on the surface plate 12 by using the toggle clamp 26 in addition to the vacuum suction mechanism shown in FIG. The toggle clamp 26 is prepared for each segment unit 50 and is arranged on the outer peripheral edge of the surface plate 12. A clamping engagement portion (recess) 30 for engaging the working point of the toggle clamp 26 is provided on the outer peripheral edge of the divided grindstone base 51.

When the segment unit 50 is mounted on the surface plate 12, after the segment unit 50 is aligned and placed on the surface plate 12, the toggle clamp 26 is locked to the grindstone base 51 of the unit 50, The vacuum pump is driven to vacuum-suck the segment unit 50 by the vacuum suction groove 25. According to the present example, by using the toggle clamp 26, the gap between the whetstone base 51 and the surface plate 12 is almost eliminated, and thus the whetstone base 51 and the surface plate 12 are removed.
It is possible to secure a shielded space for vacuum suction with one touch between and.

FIG. 5 shows an example of a mode in which the segment unit 50 is surface-sucked to the surface plate 12 only by the toggle clamp 26 without using vacuum suction. In this example, the segment unit 50 is surface-sucked by the clamp 26 and the concave and convex engagement (27A, 51A) described above.

6 and 7 show the segment unit 50.
Another mode of a mechanism for mounting the (grinding stone segment 20, grindstone base 51) on the surface plate 12 is shown. In this example, the segment unit 50 of the grindstone is fixed to the surface plate 12 by magnetic attraction.

The platen 12 is made of a non-magnetic material, and the platen 1
In FIG. 2, a magnetic attraction mechanism including a rod-shaped permanent magnet 28 and a yoke (magnetic member) 30 is installed corresponding to the position of each segment unit 50. Here, the grindstone base 51 is also made of a ferromagnetic material such as iron or nickel. Permanent magnet 2
Reference numeral 8 constitutes a rotor, and is set so that the position of the magnetic pole is changed by the rotation.

When the grindstone segment is attached, the S pole and N pole of the magnet 28 are set at a position (vertical position) orthogonal to the yoke 30 as shown in FIG.
The lines of magnetic force do not pass through 0 and the grindstone base 51, and the suction force does not work. From this state, as shown in FIG. 7, when the magnet 28 is rotated to the lateral position and the directions of the S pole and the N pole are changed to the yoke 30 side, magnetic lines of force are generated inside the yoke 30 and the grindstone base 51 as indicated by arrows in the figure. As described above, the magnetic attraction force works, and the whetstone base 51 and thus the whetstone segment 20 can be firmly surface-adsorbed on the surface plate 12.

Although some examples of fixing methods have been described above, a plurality of these attaching / detaching methods may be used at the same time. For example, in addition to the mode examples illustrated in FIGS. 3 to 7, the magnetic attraction and the clamp mechanism may be combined.

FIG. 8 shows another embodiment of the present invention.
FIG. 9 is a partially enlarged sectional view. The difference from the embodiment of FIG. 1 is that a key 29 for preventing lateral deviation of the segment unit 50 is used.

When each grinding stone segment 20 (segment unit 50) is fixed on the surface plate 12 and the semiconductor wafer 1 is flattened (polished), the wafer 1 is oriented in the direction of the arrow in FIG.
A sliding frictional force with respect to is generated. The sliding friction force increases almost in proportion to the processing pressure (load) during polishing. Generally, the polishing pressure is about 100 to 400 g / cm ² ,
When the polishing pressure exceeds 300 g / cm ² , the sliding frictional force also increases and the lateral displacement of the grindstone segment may be observed. Therefore, as shown in FIGS. 8 and 9, a convex key 29 is provided on the surface plate 12, and one end surface of the grindstone base 51 is brought into contact with and locked to the key 29. The key 29 is arranged so as to be locked to the grindstone base 51 to receive the sliding frictional force,
In this way, the lateral displacement of the segment unit 50 can be prevented. In this case, the gap 21 between the respective grindstone segments 20 can be set by the dimensional relationship of the contact portion between the key 29 and the grindstone base 51, and the gap 21 is set within the range of 0.2 to 2 mm as described above. If this is done, the optimum gap size can be reliably maintained by the presence of the key 29,
This can contribute to prevention of chipping of the grindstone segment 20. In addition, the provision of the gap 21 serves as a passage for the polishing waste liquid, which also has an effect of preventing the waste liquid from being collected in the central portion of the grindstone.

[0056]

According to the first aspect of the present invention, it is possible to achieve both segmentation of a grindstone for a semiconductor wafer, which requires high-precision surface flattening, and prevention of minute chipping of the segmented grindstone. According to the invention, the precision of the segmented grindstone is improved, and according to the third invention, the lateral displacement of the grindstone is prevented even by the sliding friction between the wafer and the segmented grindstone, and the proper grindstone arrangement is always maintained. The state can be maintained. Therefore, high precision flattening of the semiconductor is realized,
The yield in wafer fabrication can be improved.

[Brief description of drawings]

FIG. 1 is a perspective view showing a main part of a flattening apparatus for a semiconductor wafer according to an embodiment of the present invention, and a partially enlarged view of part A thereof.

FIG. 2 is a perspective view showing an arrangement state of the grindstone segments on the surface plate by partially removing the grindstone segments on the rotary surface plate of the flattening device.

FIG. 3 is a view showing an example in which a grindstone segment is mounted on a surface plate by using a vacuum suction mechanism.

FIG. 4 is a view showing an example in which a grindstone segment is mounted on a surface plate by using a vacuum suction mechanism and a clamp mechanism.

FIG. 5 is a view showing an example in which a grindstone segment is mounted on a surface plate by using a clamp mechanism.

FIG. 6 is a diagram showing an example in which a grindstone segment is mounted on a surface plate by using a magnetic attraction mechanism.

FIG. 7 is an operation explanatory view of the magnetic attraction mechanism of FIG.

FIG. 8 is a perspective view of a grindstone mechanism according to another embodiment of the present invention.

9 is a partially enlarged sectional view of FIG.

FIG. 10 is an explanatory view of a free abrasive grain polishing method which is a conventional example of a semiconductor wafer flattening apparatus.

FIG. 11 is an explanatory diagram showing a chipping mechanism that occurs at a wafer edge when a semiconductor wafer is flattened.

[Explanation of symbols]

1 ... Semiconductor wafer, 12 ... Surface plate, 13 ... Press pad, 1
4 ... Wafer holder, 20 ... Whetstone segment, 21 ... Gap, 25 ... Vacuum suction groove, 26 ... Toggle clamp, 27 ...
Center index plate, 28 ... Permanent magnet rotor, 29 ... Key,
30 ... Yoke, 50 ... Segment unit, 51 ... Whetstone base.

─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Takayasu Furukawa 882 Ichige, Itamachi, Hitachinaka City, Ibaraki Prefecture Hitachi Ltd. within the measuring instruments group (72) Inventor Masahiro Takatsuki 882, Oji, Ichige, Hitachinaka City, Ibaraki Prefecture Hitachi, Ltd. (72) Inventor, Kenji Naya, 18, Miike-cho, Kichijoin, Minami-ku, Kyoto-shi, Kyoto (56) References: JP-A-6-39733 (JP, A) JP-A 6-226608 (JP, A) JP-A-11-188642 (JP, A) JP-A-10-335276 (JP, A) JP-A-11-151675 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) H01L 21/304 B24B 1/00

Claims (5)

(57) [Claims] 1. A flattening apparatus for a semiconductor wafer, comprising: a surface plate having a rotating mechanism; and a grindstone mounted on the surface plate, for flattening a surface of a semiconductor wafer subjected to a process treatment by using the grindstone. The grindstone is a grindstone of a fixed-abrasive polishing method containing abrasive grains and a substance that binds and holds these grits, and is divided into a plurality of segments, which are similarly bonded to a divided grindstone base, A flatness of a semiconductor wafer, characterized in that the grindstone base is replaceably mounted on the surface plate in a divided unit through the grindstone base, and a gap between segments of the grindstone is set to 0.2 to 2 mm. Device. 2. A flattening apparatus for a semiconductor wafer, comprising: a surface plate having a rotating mechanism; and a grindstone mounted on the surface plate, for flattening the surface of a semiconductor wafer subjected to a process treatment by using the grindstone. , The grindstone is a grindstone of a fixed-abrasive polishing method that contains abrasive grains and a substance that binds and holds these grits, and is divided into a plurality of segments, which are also bonded to a similarly divided grindstone base, and the grindstone Characteristically, the grindstone base is detachably mounted on the surface plate in a divided unit via the base, and the segment of the grindstone is surface-adsorbed to the surface plate via each of the divided grindstone bases. And a semiconductor wafer flattening apparatus. 3. The segmented grindstone is vacuum-adsorbed, or magnetically adsorbed, or a combination of the vacuum adsorbing and clamping mechanism, or the magnetic, through each of the divided grindstone bases. The semiconductor wafer flattening apparatus according to claim 2, wherein the surface of the surface plate is attracted to the surface plate by a combination of suction and a clamp mechanism. 4. A semiconductor wafer flattening apparatus comprising: a surface plate having a rotating mechanism; and a grindstone attached to the surface plate, for flattening the surface of a semiconductor wafer subjected to a process treatment using the grindstone. , The grindstone is a grindstone of a fixed-abrasive polishing method that contains abrasive grains and a substance that binds and holds these grits, and is divided into a plurality of segments, which are also bonded to a similarly divided grindstone base, and the grindstone The grindstone bases are mounted in a replaceable manner on the surface plate in a divided unit of the grindstone base via the base, and the sliding frictional force due to the flattening process of the semiconductor wafer is divided on the surface plate. A flattening apparatus for a semiconductor wafer, wherein a plurality of keys are arranged so as to be locked and received by the. 5. The flattening apparatus for the semiconductor wafer according to claim 4, wherein the size of the gap between the segments of the grindstone is defined by the key.