JP2000000757A - Polishing device and polishing method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce the total load for pressurization, and to almost uniformly polish a wafer by setting the size of a polishing pad smaller than the size of a polishing object member. SOLUTION: A polishing device has the polishing pad part 10 and the polishing object member part (the wafer part) 20. The polishing pad part 10 has a polishing pad 4 having the size sufficiently smaller than the size of a wafer 1 being a polishing object member, a head 30 composed of a base 5 for holding this polishing pad 4 and a vibration mechanism 9, a rectilinearly moving mechanism and a pressurizing mechanism (showing only the pressurizing direction 7). Since a relative speed of the polishing pad 4 and the polishing object surface of the wafer 1 becomes almost uniform on the whole surface of the polishing pad 4 since the size of the polishing pad 4 is sufficiently smaller than the size of the wafer 1, the whole surface of the polishing pad 4 easily strikes on the wafer surface 1, so that polishing pressure with the polishing object surface of the wafer 1 becomes uniform on the whole polishing surface of the polishing pad 4.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a polishing apparatus for flattening semiconductor devices on a wafer in a semiconductor process.

[0002]

2. Description of the Related Art In a semiconductor process for forming a semiconductor device on a wafer, a patterned electrode layer and a dielectric layer as an interlayer insulating film of the electrode layer are laminated. A step which is an influence is caused, and the existence of the step becomes a hindrance to a semiconductor process such as a subsequent exposure step. Therefore, a demand for flattening the step is increasing with a high definition of a semiconductor device pattern.
Further, there is a high demand for so-called inlay (plug, damascene) for embedding a metal electrode layer. In this case, removal and flattening of an extra metal layer after lamination of the metal layer are indispensable steps.

As a method of flattening the surface of a semiconductor device, a chemical mechanical polishing (Chemical Mechanical Polishing) method is used.
ng or Chemical Mechanical Planarization (hereinafter referred to as CMP) technology is considered a promising method. C
A general method of MP is to attach a polishing pad made of a polishing cloth or a polymer material on a polishing platen, and drop a slurry-type polishing agent (hereinafter simply referred to as a polishing agent) while coating the polishing plate with a polishing pad. In this method, a polishing head holding a wafer as a polishing member is rotated and vibrated to polish a semiconductor device surface layer in the middle of the process.

FIG. 5A shows the most common conventional disk-shaped polishing apparatus. 100 is a polishing platen called a platen, 101 is a polishing pad, 102 is a wafer, 1
03 is a polishing head for holding a wafer, and 104 is a polishing agent supply mechanism. This polishing apparatus rotates the platen and the polishing head in the same direction at substantially the same rotational speed while applying a load P to the surface to be polished of the wafer, and further oscillates the polishing head, thereby causing a relative movement between the wafer and the polishing pad. An apparatus that imparts motion and polishes the surface of a semiconductor device on a wafer. FIG. 5B is a diagram of the disk-shaped polishing apparatus of FIG. 5A as viewed from above.

FIG. 5C shows a conventional belt-type polishing apparatus often used for polishing an optical disk. The polishing pad 105 has a belt shape and is fixed to a conveyor belt material. This is a polishing method in which a belt-shaped polishing pad is moved linearly in one direction, and the polishing is performed by rotating a polishing head 106 to which a wafer as a member to be polished is fixed. The polishing pad 105 moves linearly, and has a motion corresponding to the vibration.

FIG. 5D shows the polishing pad 101 eccentrically rotated (rotated by a satellite such as an ellipse) to be polished (wafer) 102.
This is a type of polishing apparatus that rotates. The oscillating motion is performed using eccentric rotation.

[0007]

The conventional CMP polishing apparatus has the following problems. As can be easily understood from the drawings, the conventional CMP polishing apparatus shown in FIGS. 5A and 5C has a large polishing pad area with respect to the wafer area, so that the polishing apparatus becomes large and the installation space for the apparatus is increased. There was a problem that became wide. The problem is that semiconductor process wafers have diameters of more than 8 inches, 12 inches,
Since the size of the polishing apparatus is increasing to 6 inches, the polishing apparatus for the semiconductor process must be installed in a clean room where the equipment cost is extremely high, which causes an increase in the manufacturing cost and is a serious problem for the manufacturer.

In the conventional apparatus, the surface to be polished of the wafer faces downward as shown in FIGS. 5 (a), 5 (c) and 5 (d).
When the wafer was transferred from the wafer carrier to the polishing apparatus, the wafer surface had to be inverted. For this reason, it was necessary to equip the device with a reversing mechanism. This reversing mechanism not only increases the size of the entire system, but also adds a reversing process to the system.
The yield of the entire P process was reduced. The reason for the decrease in the yield is that the reversing mechanism itself pollutes the polishing environment, and not only the polishing yield decreases due to the contamination of the polishing environment, but also the contamination of the reversing mechanism due to use in the environment where the abrasive exists (due to the abrasive). This is because the danger that the reversing mechanism causes an operation failure cannot be ignored.

[0009] Furthermore, a conventional CMP polishing apparatus has a structure shown in FIG.
As can be seen from the figure of (a), since the plane dimension of the platen to which the polishing pad is attached is large and the rotation axis of the platen and the pressing axis of the polishing head are largely eccentric, the pressure on the member to be polished (wafer) is increased. Thereby, the platen is easily deformed. In order to prevent this deformation and maintain the flatness of the platen surface, it is necessary to increase the thickness of the platen or to use a static pressure bearing, etc., and as a result, the CMP polishing apparatus inevitably becomes heavy. Did not get. The CMP polishing apparatus has a total weight of 2 to 4 tons, and requires a building with a large floor load to install the apparatus, which causes an increase in manufacturing cost.

Furthermore, in the conventional CMP polishing apparatus, it has been difficult to keep the relative speed with respect to the polishing pad uniform at each position on the surface to be polished of the wafer. The polishing rate is said to be proportional to the relative speed between the wafer and the polishing pad. Therefore, it has been difficult for a conventional CMP polishing apparatus to maintain a uniform polishing rate at each position on the surface to be polished of the wafer. Further, in the conventional CMP polishing apparatus of FIG. 5A, as shown in FIG. 5B, the residence time of the wafer at each position on the polishing pad surface is different, so that the surface of the polishing pad is not consumed. Become uniform,
At the stage of performing continuous polishing, it was necessary to maintain the surface state by dressing operation (with complicated dressing) of the polishing pad. Generally, in the dressing process, diamond abrasive grains are used, and the abrasive grains fall during dressing, causing scratches on the wafer surface and causing a decrease in yield, and because the polishing pads are scraped off by dressing, wear of the polishing pads And the replacement period of the polishing pad is shortened, thereby increasing the manufacturing cost.

The present invention provides a CM for solving the above problems.
An object of the present invention is to provide a P polishing apparatus.

[0012]

SUMMARY OF THE INVENTION In order to solve the above problems of increasing the size and weight, the present invention is to reduce the amount of eccentricity between the pressing center of the polishing head and the rotation center of the wafer. Tried. Therefore, the diameter of the platen (polishing pad) was reduced to be smaller than the diameter of the wafer. As a result, even if the platen (polishing pad) was made thinner and lighter, no significant deformation occurred in the platen, and preferable polishing could be performed. Further, by reducing the size of the polishing pad, the speed due to the vibration of the polishing pad was increased, and the polishing rate could be increased. Polishing is performed only by rotation of the wafer and high-speed vibration of the polishing pad, or by rotation of the wafer and vibration and rotation of the polishing pad. Since the polishing pad is small, the polishing pad can be disposed above the wafer, and the wafer being polished can be disposed with the surface to be polished facing upward. Rotation speed of the wafer according to the relative position of the polishing pad with respect to the wafer,
The relative speed of the polishing pad to the wafer at each position on the entire surface to be polished of the wafer by changing at least one selected from the polishing pressure, the moving speed of the polishing pad, the vibration frequency of the polishing pad, and the vibration amplitude of the polishing pad. Can be made uniform. Further, even if the relative speed was not made uniform, the polishing speed could be made uniform by changing at least one selected from the polishing pressure and the moving speed of the polishing pad.

For this reason, the present invention firstly provides a polishing apparatus having a member to be polished having a holding portion to which the member to be polished is fixed, and a polishing pad having a head to which the polishing pad is fixed. And a polishing apparatus wherein the size of the polishing pad is smaller than the size of the member to be polished. Secondly, "the member to be polished further has a rotating shaft and a rotating mechanism for rotating the member to be polished together with the holding portion, and the polishing pad portion vibrates the polishing pad. A polishing apparatus according to claim 1 (claim 2), further comprising a vibration mechanism.

Thirdly, there is provided "a polishing apparatus according to claim 2, wherein the polishing pad section further includes a moving mechanism for moving the polishing pad." Fourthly, "the head further has an abrasive supply hole for supplying an abrasive.
A polishing apparatus according to any one of claims 1 to 3 (Claim 4). "

Fifth, "the surface to be polished of the member to be polished is upward with respect to the direction of gravity.
A polishing apparatus according to any one of claims 1 to 4 (Claim 5). " Sixth, "the apparatus further includes a housing having at least a ceiling, a floor, a left wall, a right wall, and a space therein, and which is substantially integrated with the polishing pad and the polishing pad. The member to be polished is fixed to any one or more of the ceiling or the floor or the left wall or the right wall,
2. The storage device according to claim 1, wherein the storage device is housed in the space.
A polishing apparatus according to any one of claims 1 to 5, (claim 6). "

Seventh, the polishing according to any one of claims 2 to 6, wherein the thickness of the rotating shaft is at least 1/2 ^1/2 of the diameter of the member to be polished. Device (Claim 7) "is provided. Eighth, "a polishing method for polishing using the polishing apparatus according to any one of claims 2 to 7, wherein the rotation of the member to be polished is 10rpm or more and 300rpm or less,
And a polishing method for polishing the polishing pad at a frequency of 30 Hz or more and 10 KHz or less.

Ninth, there is provided a polishing method for polishing using the polishing apparatus according to any one of claims 2 to 7, wherein the polishing is performed from a center position of the member to be polished in order to uniformly polish the member to be polished. One or more selected from the rotation speed of the member to be polished, the polishing pressure, the moving speed of the polishing pad, the frequency of the polishing pad, and the vibration amplitude of the polishing pad according to the distance to the center position of the polishing pad at the center. A polishing method characterized by changing the thickness (claim 9). "

Tenthly, there is provided a polishing apparatus according to any one of claims 1 to 7, wherein the member to be polished is a wafer. Eleventh, there is provided "a polishing method according to any one of claims 8 to 9, wherein the member to be polished is a wafer (claim 11)."

[0019]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, the present invention will be described by way of examples.
The scope of the present invention is not limited to the scope of the description and the drawings used for the description, but includes all the scope that can be easily modified by those skilled in the art. FIG. 1A is a side view of the polishing apparatus according to the present embodiment, and FIG. 1B is a top view.

As shown in FIG. 1A, a polishing apparatus according to an embodiment of the present invention includes a polishing pad section 10 and a member to be polished (wafer section) 20. The polishing pad section 10 includes a polishing pad 4 having a size sufficiently smaller than the size of the wafer 1 to be polished, a base 5 holding the polishing pad 4, and a vibration mechanism 9 (the vibration direction is indicated by an arrow 11). And a pressurizing mechanism (showing only the pressurizing direction 7). The wafer unit 20 includes a holding unit 2 that holds the wafer 1.
And a rotation shaft 3 and a rotation mechanism 8 for rotating the wafer 1. FIG. 1B is a view seen from above.

In this polishing apparatus, polishing is performed as follows. The polishing pad 4 is pressurized 7 on the surface to be polished of the wafer 1 by the pressurizing mechanism, and the rotational movement 16 of the wafer 1 provided by the rotating mechanism 8 via the rotating shaft 3 and the polishing pad 4 provided by the vibration mechanism 9. By vibrating motion 11 and linear movement 12 for moving polishing pad 4 that makes vibrating motion 11 from the edge of the wafer toward the center, the entire surface to be polished of wafer 1 is polished. Further, the rotation speed of the rotation of the holding portion of the wafer is made variable, and the vibration motion 11 and the linear movement 12 of the polishing pad 4 are given independently.

Here, the rotational speed of the wafer 1 is the slowest when the polishing pad 4 is at the outermost side of the wafer, and as the polishing pad 4 moves toward the center of the wafer by the linear motion 12, the distance from the center of the wafer increases. Raise in response to. This makes it possible to make the relative speed of the polishing pad relative to the wafer uniform at all points on the surface to be polished of the wafer. The relative speed is the rotational motion of the wafer 1
3 is given by the combined speed of the speed of the polishing pad 11 and the speed of the vibration of the polishing pad 11, the relative speed can be made uniform even if the frequency or amplitude of the polishing pad is adjusted in addition to the rotational speed of the wafer. . As a result of making the relative speed at each position on the surface to be polished of the wafer uniform, the polishing speed can also be made uniform.

According to the distance of the polishing pad from the center of the wafer, the polishing speed can be adjusted even if the polishing pressure and / or the moving speed of the polishing pad are adjusted, without making the relative speed of the polishing pad to the wafer uniform. Can be made uniform. Further, in the conventional polishing apparatus, the shape of the polishing pad surface is deformed due to uneven polishing of the polishing pad, and a dressing operation is required to correct the deformation. In this polishing apparatus, the relative speed of the polishing pad at each position of the surface to be polished of the wafer is basically made substantially uniform, and the polishing pad is uniformly worn, especially in the case of a hard polishing pad having a groove structure. Furthermore, the need for a dressing operation using diamond abrasive grains is eliminated.

The reason is that the relative speed between the polishing pad and the surface to be polished of the wafer becomes almost uniform over the entire surface of the polishing pad because the size of the polishing pad is sufficiently smaller than the size of the wafer. This is because the entire surface of the polishing pad easily hits the wafer surface, and therefore the polishing pressure with the surface to be polished of the wafer becomes uniform over the entire polishing surface of the polishing pad.

The size of the polishing pad (the diameter of the polishing pad in the case of a circular polishing pad, the average of the length of the long side and the length of the short side in the case of a rectangular polishing pad) is 5 to 50% of the diameter of the wafer.
Is preferred. If the polishing rate is too small, the polishing rate will decrease. If the rate is too high, uniformity of the polishing rate cannot be ensured. The rotation speed of the wafer is preferably 10 rpm or more and 300 rpm or less, and more preferably has a variable mechanism.

In order to avoid distortion of the polished surface of the wafer 1 due to pressurization of the polished surface, the diameter of the rotating shaft 3 is set to be equal to the diameter of the wafer.
/ 2 ^1/2 or more is most preferable. In order to ensure a sufficient polishing speed, the frequency and amplitude of the vibration of the polishing pad are determined so that the speed of the polishing pad due to the oscillating motion becomes high. If the frequency of the vibration of the polishing pad is too low, the speed of the polishing pad will not increase, and if it is too high, the motion of the vibration of the polishing pad will be unstable. In this sense, the frequency of vibration of the polishing pad is preferably 30 Hz.
It is not less than 10 KHz and more preferably has a frequency variable mechanism.

If the amplitude of the vibration of the polishing pad is too small, it becomes difficult to increase the speed of the polishing pad, and if it is too large, it becomes difficult to increase the uniformity of the polishing rate on the wafer surface. In this sense, the amplitude of the vibration is preferably 100
It is not less than μm and not more than 10 mm, and more preferably has an amplitude variable mechanism. Twice the amplitude here corresponds to the maximum vibration width of the vibration motion of the polishing pad.

As a vibration mechanism of the polishing pad, an ultrasonic motor, an electromagnetic motor, an ultrasonic linear motor, an electromagnetic linear motor, a piezo element, and a voice coil are preferably used.
Since the polishing pad can reduce the diameter of the polishing pad and make it lighter, the polishing pad can be installed above the CMP apparatus, and the polished surface of the wafer can be arranged upward with respect to the direction of gravity. It becomes possible. Such an arrangement is difficult because the polishing pad is large in an ordinary CMP apparatus. In the semiconductor process, the pre-process of the CMP polishing process is usually completed with the surface to be polished of the wafer facing upward with respect to gravity. In the conventional CMP polishing apparatus, the polishing head was always positioned above the polishing pad, so that the surface to be polished of the wafer had to be turned downward, and a wafer reversing mechanism for that was required. In the CMP polishing apparatus of the present invention, since the surface to be polished can be polished in an upward state,
This eliminates the need for a wafer reversing mechanism used in a conventional CMP polishing apparatus, and further eliminates a wafer drop accident caused by the reversing mechanism.

Further, in the present polishing apparatus, since the size of the polishing pad is smaller than the size of the wafer, an optical end point detecting mechanism is used as an end point detecting mechanism, and the probe light is not polished from the upper side (the upper side). The remaining film thickness and the end point can be preferably detected by analyzing reflected light or transmitted light obtained by irradiating the surface with no polishing pad.

The polishing agent is supplied from a polishing agent supply mechanism above the surface to be polished of the wafer. It is also possible to provide a hole for supplying the polishing agent at the center of the polishing pad and supply the polishing agent from the hole. Polisher pad hardness is AskerC
Those having a hardness of 70 to 98 are preferably used. A polishing pad having a hardness in this range has good polishing performance such as a degree of eliminating a step in a pattern of a semiconductor device or the like.

As described above, in the polishing apparatus of the present embodiment, since the size of the polishing pad is small, it is possible to vibrate the polishing pad at a high speed. As a result, a sufficient polishing speed can be secured, and Even if the thickness of the holding portion is reduced, deformation of the polished surface due to pressure can be prevented, and the polishing apparatus can be reduced in weight and size. Example 1 Polishing was performed using the polishing apparatus shown in FIG. As the polishing pad, a polishing pad having a spiral groove of 0.5 mm pitch and a lattice groove of 5 mm pitch was used based on an epoxy resin molded into 10 mm × 10 mm, and this was attached to the base 5 of the polishing head 30. The hardness of the polishing pad was 90 with AskerC. A 5 kg load was applied to the base. Further, a piezo element (not shown) was used to reciprocate the substrate. As a member to be polished, a 6-inch wafer having a 1 μm-thick thermal oxide film formed thereon was used. The wafer was held by a vacuum chuck.

The polishing condition is that the load on the wafer surface is 5000
g / cm ² , the amplitude of vibration of the polishing pad is ± 0.10 mm
(The maximum vibration width was 0.20 mm), and the frequency was variable at 3.5 KHz at the start of polishing. The polishing pad 11 is moved along the radius of the surface to be polished of the wafer 1 by a linear moving mechanism (only the moving direction is indicated by 12). During this time, the relative speed between the wafer and the polishing pad is 2.2 m in RMS value. The frequency was adjusted to maintain / sec.

As a polishing agent, Cabot SS12 was supplied at a rate of 5 ml / min through a hole formed in the center of the polishing pad. The average polishing rate of the entire wafer surface was 300 nm / min, and the uniformity was within ± 5%. [Embodiment 2] The apparatus of FIG. 3 is basically an apparatus in which an optical monitor 13 is attached to the apparatus of FIG. During polishing, the unpolished portion of the surface to be polished is irradiated with probe light, and the reflectance information of the reflected light is monitored. The resulting waveform changes as the film thickness changes, and the timing of the end point of polishing is detected. Was available to The optical end point can be easily detected without processing the polishing head.

Further, by moving the optical monitor 13 in synchronization with the linear movement of the polishing pad and irradiating the wafer portion immediately after polishing with probe light, the distribution of the remaining film thickness on the surface to be polished can be measured immediately. By feeding back a signal for correcting the distribution of the remaining film thickness to be uniform at an appropriate timing of the polishing progress to the control system of the vibration mechanism of the polishing pad, the remaining film is formed at each position on the entire surface to be polished of the wafer. It is possible to make the thickness distribution uniform. [Example 3] Polishing was performed under the same conditions as in Example 1 using a wafer with a pattern in Example 1 and the degree of level difference elimination was measured. As a result, extremely good results were obtained without dishing. [Embodiment 4] As shown in FIG. 4, a mechanism for pressing a surface to be polished of a wafer was provided by attaching the wafer unit 20 and a polishing pad unit 10 to a casing which is a structure integrally formed. . Not only can the entire device be smaller and lighter,
Since the size of the polishing pad is small, there is an advantage that an extremely small load needs to be applied to obtain a polishing pressure required for polishing. Embodiment 5 FIGS. 2A, 2B, 2C and 2D show a polishing pad used in the polishing apparatus of the present invention. (A) is a rectangular polishing pad and (c) is a circular polishing pad, which can be used depending on the application. In (b) and (d), a hole 6 for supplying an abrasive was provided at the center of the polishing pad. Thus, the polishing agent can be supplied from the polishing pad side.

In these polishing pads, grooves are formed to ensure the fluidity and supply of the abrasive. Although the groove structure is basically a lattice groove, a spiral groove and a concentric groove may be combined. Example 6 200-inch 6-inch wafers were polished by the polishing apparatus of Example 1, and the change in uniformity of the remaining film thickness of the wafer and the change in polishing rate as an average over the entire wafer surface were measured. It was found that there was almost no change even after the polishing, and a favorable result was obtained.

As described above, in the first embodiment, the vibration direction of the polishing pad is parallel to the moving direction of the polishing pad. However, the vibration direction may be the vertical direction (rotation direction of the wafer) or another appropriate direction. Not even. As described above, the first to sixth embodiments have been described with reference to the drawings. However, the embodiments are not limited to these drawings, and the present invention is not limited to these embodiments.

[0037]

As described above, according to the present invention, by making the size of the polishing pad sufficiently smaller than the size of the member to be polished, the total load for pressing can be reduced, and the entire polishing apparatus is also reduced. As a result, the wafer can be arranged upward and not only is resistant to trouble, but also the wafer is almost uniformly polished, and the degree of eliminating the step is good. In addition, since the wear rate at each position on the polishing pad surface is also uniform, the life of the polishing pad can be extended without dressing. Further, since the size of the polishing pad is small, maintenance for replacement can be easily performed. Furthermore, because partial polishing is possible,
Secondary correction polishing is also possible. Furthermore, it is possible to easily detect the optical end point structurally.

[Brief description of the drawings]

FIG. 1 is a diagram illustrating a polishing apparatus according to an embodiment of the present invention and a polishing apparatus according to a first embodiment.

FIG. 2 is a polishing pad according to a fifth embodiment of the present invention.

FIG. 3 shows a polishing apparatus provided with an optical monitor according to a second embodiment of the present invention.

FIG. 4 is an integrated polishing apparatus according to a fourth embodiment of the present invention.

FIG. 5 is a conventional polishing apparatus. (A) Disc-shaped polishing device (b) Area in which polishing pad is used in polishing machine of (a) (c) Belt-shaped polishing device (c) Eccentric, rotating type polishing device

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Polished member (wafer) 2 Holder 3 Rotating shaft 4 Polishing pad 5 Base (platen) holding polishing pad 6 Hole for supplying abrasive 7 Shows pressure 8 Rotation mechanism 9 Vibration mechanism 10 Polishing pad section 11 Shows vibration direction 12 Shows linear movement direction of polishing pad 13 Optical monitor 14 Shows irradiation light and reflected light 15 Shows linear movement of optical monitor 16 Rotational motion 20 Member to be polished (wafer part) 30 Head 100 Platen 101 Polishing pad 102 Wafer 103 Polishing head for holding wafer 104 Abrasive supply mechanism 105 Belt-like polishing pad 106 Polishing head

Claims (11)

[Claims] 1. A polishing apparatus comprising: a member to be polished having a holding portion to which a member to be polished is fixed; and a polishing pad having a head to which a polishing pad is fixed, wherein the polishing pad has a size. A polishing apparatus characterized in that it is smaller than the size of the member to be polished. 2. A polishing apparatus according to claim 1, wherein said member to be polished further comprises a rotating shaft and a rotating mechanism for rotating said member to be polished together with said holding portion, and said polishing pad portion causes said polishing pad to vibrate. The polishing apparatus according to claim 1, further comprising a vibration mechanism. 3. The polishing apparatus according to claim 2, wherein said polishing pad section further includes a moving mechanism for moving said polishing pad. 4. The head according to claim 1, wherein said head further has an abrasive supply hole for supplying an abrasive.
The polishing apparatus according to claim 1. 5. The polishing apparatus according to claim 1, wherein a surface to be polished of said member to be polished is upward with respect to a direction of gravity. 6. A polishing apparatus further comprising a substantially integrated housing having at least a ceiling part, a floor part, a left wall part, a right wall part, and a space inside the polishing pad part and the polishing pad part. The member to be polished is fixed to any one or more of the ceiling, the floor, the left wall, and the right wall, and is housed in the space. Item 1
5. The polishing apparatus according to claim 1. 7. The apparatus according to claim 2, wherein the thickness of said rotating shaft is at least 1/2 ^1/2 of the diameter of said member to be polished.
The polishing apparatus according to any one of claims 1 to 6. 8. A polishing method for polishing using the polishing apparatus according to claim 2, wherein the rotation of the member to be polished is from 10 rpm to 300 rpm, and the vibration of the polishing pad is from 30 Hz to 10 KHz. A polishing method characterized by polishing below. 9. A polishing method for polishing using the polishing apparatus according to claim 2, wherein the polishing is performed from a center position of the member to be polished to a center of vibration for uniform polishing of the member to be polished. Changing at least one selected from the rotation speed of the member to be polished, the polishing pressure, the moving speed of the polishing pad, the frequency of the polishing pad, and the vibration amplitude of the polishing pad according to the distance to the center position of the polishing pad. A polishing method characterized by the above-mentioned. 10. The polishing apparatus according to claim 1, wherein said member to be polished is a wafer. 11. The polishing method according to claim 8, wherein said member to be polished is a wafer.