JP2003324088A - Polishing method and polishing device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide polishing method and device that rarely damages a material forming a target to be polished. <P>SOLUTION: In the polishing method for polishing a surface to be polished by pressing polishing pad rotated by a motor to the surface to be polished, the torque of the motor is controlled to control a stress in the intra-surface direction of the surface to be polished. Thereby the stress of the intra-surface direction which is a direct cause to damage the surface to be polished can be controlled. Thus the surface to be polished can be flattened with hardly damaging a target to be polished. <P>COPYRIGHT: (C)2004,JPO

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a polishing method and a polishing apparatus. More specifically, the present invention relates to a polishing apparatus and a polishing method suitable for manufacturing a semiconductor device.

[0002]

2. Description of the Related Art In recent years, electronic devices such as television receivers, personal computers and mobile phones have been downsized,
High performance and multi-functionality are required, and LSI, which is a semiconductor element mounted in these electronic devices, is required to have higher speed operability and power saving. In order to meet these demands, miniaturization of semiconductor elements and progress of multilayer structure have been advanced, and optimization of materials for forming semiconductor elements has been performed. At the present time, there is a demand for a wiring forming technology capable of coping with the 0.1 μm generation, which is a semiconductor device design rule, and the subsequent generations.

Further, in the manufacturing process of semiconductor devices, with the miniaturization of wirings formed on semiconductor elements, it has become difficult to form wirings with sufficient accuracy by wiring formation by photolithography. Therefore, a metal is embedded in a groove-shaped wiring pattern formed in advance on the interlayer insulating film, and a chemical mechanical polishing method (hereinafter referred to as CM) is used.
A method of forming wiring by removing excess metal by the P method) is widely performed.

[0004]

By the way, in response to the demand for further speeding up and power saving of LSI in the future, the CR of wiring is required.
In order to reduce the delay, use of an ultra-low dielectric constant material such as porous silica having a dielectric constant of 2 or less as a substrate material of a semiconductor element is being studied in addition to copper wiring.

However, the processing pressure applied to the wafer by the conventional CMP method is 4 to 6 psi (1 psi = about 70 g).
/ Cm ² ), and when forming a wiring on a fragile ultra-low dielectric constant material, it becomes difficult to form a good wiring due to crushing, cracking or peeling.

Further, the pressure at which these ultra-low dielectric constant materials are considered to be mechanically durable is 1.5 psi (105 g / c).
When the CMP pressure is reduced to about m ² ) or less, it is difficult to form the wiring without damaging the ultra-low dielectric constant film, for example, the polishing rate required for a normal production rate cannot be obtained. .

Further, in the ordinary CMP method, the material removal amount is in accordance with the so-called Preston's equation, the removal amount = proportional constant ×
It is expressed as relative speed x time. Conventionally, in general, the polishing amount is after the quality control of the polishing pad and slurry used,
The present condition is that the polishing apparatus is controlled by the polishing pressure and the polishing time. The commercially available CMP apparatus basically has only a mechanism for controlling the vertical pressing pressure and the polishing time.

Here, Lo formed of an ultra-low dielectric constant material
The breakdown of the w-k film is inferred from the breakdown situation and the normal stress F
Although the shear stress Ft in the tangential direction is dominant rather than the shear stress n, the vertical stress Fn is The Low-k film is easily destroyed if there is a sudden change in the shear stress Ft that occurs due to some factor (slurry supply status, pad surface status, etc.) even if the low-k film is managed by lowering it.

For example, an experiment conducted by the inventor of the present application will be described with reference to FIG. FIG. 5 shows the surface of the wafer 62 among the stresses applied to the surface of the wafer 62 when the polishing liquid (slurry) is interposed between the wafer 62 on which the porous silica film is formed and the polishing pad 61. FIG. 6 is a diagram illustrating an experiment in which the damage state of the wafer 62 is investigated with the vertical stress Fn applied in the direction perpendicular to the as a parameter. Here, as a result of using a general-purpose polishing pad and using an alumina slurry as the polishing liquid, in this experiment, as shown in Table 1, damage to the wafer was confirmed at a normal stress of 210 g / cm ² or more.

[Table 1]

However, as shown in FIG. 6, the friction coefficient between the wafer and the polishing pad fluctuates depending on the state of the wafer surface, which is the surface to be polished. The shear stress, which is a stress component parallel to the surface to be polished, fluctuates rather than the vertical stress with a sensitivity of 5 times. Therefore, even if the vertical stress is controlled to 140 g / cm ² or less as shown in Table 1, the wafer may be damaged by the shear stress. Therefore, it is important to manage not only the polishing condition based on the vertical stress on the wafer but also the stress component acting in the direction parallel to the surface to be polished.

Therefore, in view of the above problems, the present invention flattens a metal film to be a wiring in manufacturing a semiconductor device and polishes a fragile material forming an object to be polished with almost no damage. It is an object to provide a method and a polishing device.

[0012]

In the polishing method of the present invention, a polishing pad driven to rotate by a motor is pressed against a surface to be polished, and the surface to be polished is polished, the torque of the motor is controlled, It is characterized in that the stress component in the in-plane direction of the surface to be polished is controlled. Therefore, by pressing the wafer against the polishing pad so that the stress component in the in-plane direction of the surface to be polished becomes a predetermined value or less,
The metal film formed on the surface of the wafer can be flattened and wiring can be formed with almost no damage to the wafer.

Further, the polishing apparatus of the present invention comprises a polishing pad for polishing a surface to be polished, a motor for rotating the polishing pad, and a stress in the in-plane direction of the surface to be polished by controlling the torque of the motor. And a torque control mechanism for controlling the components. Therefore, by performing the polishing while controlling the motor torque, the wiring can be formed with almost no damage to the wafer.

[0014]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, a polishing method and a polishing apparatus of the present invention will be described in detail with reference to FIGS.

FIG. 1 is a schematic configuration diagram of a polishing apparatus of the present invention. The polishing apparatus 1 includes a polishing apparatus body 2, a motor driver 3 and a control unit 4 connected to the polishing apparatus body 2, and a control unit 4. The operation unit 5 connected to the.

The polishing apparatus main body 2 holds a wafer 11 as an object to be polished and presses it against a polishing pad 20, a polishing pad 20 abutting against a surface to be polished of the wafer 11, and a polishing pad. Although it is a rotary type polishing apparatus having a driving unit 30 for driving 20, the polishing apparatus of the present invention is not limited to the rotary type, and is not limited to the linear type.
It is also suitable for a polishing apparatus having a polishing type, a partial type, an orbital type and other polishing mechanisms.

The pressing mechanism 10 for pressing the wafer 11 against the polishing pad 20 is a wafer chuck 1 for holding the wafer.
2 and a wafer rotation shaft 1 connected to the wafer chuck 12.
3, and a counterweight 16 connected to the movable portion 14 via a roller 15 and a movable portion 14 which is vertically movable in the drawing. Further, the pressing mechanism unit 10 cancels the self-weight of the wafer chuck 12, the wafer rotation shaft 13, and the respective parts incidental to the pressing mechanism unit 10, and the pressing pressure for pressing the wafer 11 against the polishing pad 20 is, for example, 0.1 psi (7 g). / Cm ² ) It has a function that can be set in units. In particular, when the insulating film formed on the wafer 11 is a material having a relatively low mechanical strength such as porous silica, the pressing pressure is set to 0.5, for example.
To 1.5 psi (35 to 105 g / cm ² ).

The movable part 14 is moved in the vertical direction by, for example, an air cylinder or a servomotor whose pressure can be controlled to position the wafer 11 and to polish the polishing pad 20.
A pressing mechanism that presses the wafer 11 against the
Based on a control signal transmitted from the wafer 11, the surface 11a to be polished of the wafer 11 can be moved in the vertical direction, which is the vertical direction in the drawing.

The polishing pad 20 is fixed to a surface plate 21 having electrodes 22 formed thereon, and a polishing pad rotating shaft 31 connected to the surface plate 21 rotates to rotate the polishing pad 20 while rotating the wafer. The surface 11a to be polished 11 is polished. Further, the peripheral edge of the polishing pad is fixed to the wafer edge sliding rings 25a and 25b connected to the anode of the external power source, and when polishing the wafer 11, the surface 11a to be polished is polished.
When the wafer edge sliding rings 25a and 25b are in contact with each other, the surface 11a to be polished serves as an anode. In addition, the electrode 22
Is connected to an external electrode to serve as a cathode, and the polishing pad 20 together with the surface plate 21 is filled with the electrolytic solution 23 in the electrolytic solution 24.
Polishing is performed in a state of being immersed therein, and it is possible to perform polishing that combines mechanical polishing and electrolytic polishing on the surface 11a to be polished. Further, the electrolytic solution tank 24 may be provided with a transfer section that transfers the wafer 11.

Further, as the material for forming the polishing pad 20, a foamed material such as polyurethane foam, polypropylene polypropylene or polyvinyl acetal can be used, and the Young's modulus representing the hardness of the material forming the polishing pad 20 is , For example 0.02 to 0.10 GPa
The degree is suitable. Further, when the material forming the polishing pad 20 is hardly impregnated with the electrolytic solution, the polishing pad 2
The polishing pad 20 may be provided with a supply hole for sufficiently supplying the electrolytic solution between 0 and the surface 11a to be polished of the wafer 11. Further, in order to conduct electricity from the electrode 22 to the surface 11 a to be polished of the wafer 11, it is sufficient to form a hole in the surface plate 21 between the polishing pad 20 and the electrode 22 for interposing the electrolytic solution.

The drive unit 30 includes a polishing pad rotating shaft 31 for rotating the polishing pad 20 at a predetermined rotation speed, a motor 32 for generating a driving force for rotating the polishing pad 20, and a motor 32 to the polishing pad rotating shaft 31. It is composed of a pulley 33 that transmits a driving force, a belt 34, and a rotary joint 35. The polishing pad rotating shaft 31 is used for the wafer 11
When the insulating film formed in the above is a material such as porous silica having a lower mechanical strength than the conventionally used silicon oxide film-based material, for example, the rotation speed is 60 to 120.
Can be set to rpm.

The motor 32 generates a driving force for rotating the polishing pad 20 by a motor driving current supplied from the motor driver 3. When polishing the wafer 11 by bringing it into contact with the polishing pad 20, the surface to be polished 1 of the wafer 11
The torque of the polishing pad 20 may vary depending on conditions such as the state of 1a. At this time, the fluctuation of the torque of the polishing pad 20 is acquired by the motor driver as a motor torque signal of the motor 32 and transmitted to the control unit 4.

The control unit 4 compares the obtained motor torque signal with the polishing condition input from the operation unit 5 or the condition stored in the storage unit installed in the control unit 4 in advance, and the pressure drive signal is obtained. Is transmitted to the movable part 14 and the wafer 11
Position in the figure and the polishing pad 20 of the wafer 11
Controls the pressing force against. Here, the fluctuation of the torque of the polishing pad 20 corresponds to the fluctuation of the shear stress which is the stress component in the in-plane direction of the surface 11a to be polished among the stresses applied to the surface 11a to be polished, and the torque of the polishing pad 20 By controlling the fluctuation, it becomes possible to control the shear stress applied to the surface 11a to be polished, and the damage to the surface 11a to be polished can be reduced. Therefore, according to the driving force of the motor 32 corresponding to the torque of the polishing pad 20, the wafer 11
By controlling the pressing force of the polishing pad 20 against the polishing pad 20, an excessive load may be applied to the surface 11a to be polished, as compared with the case where polishing is performed by setting only the polishing time and the load for pressing the wafer 11 against the polishing pad 20. Almost never. Therefore, even when the insulating film is formed on the wafer 11 by using a material having a relatively low mechanical strength such as porous silica, the shear stress in the in-plane direction of the surface to be polished 11a, which is considered to be the direct cause of the damage of the insulating film, is excessive. Can be reduced.

Here, the results of calculation by the present inventor of the shear stress, which is a stress component parallel to the surface 11a to be polished, are shown based on the values of the following parameters. As a result, the surface to be polished 11 is polished by using the polishing apparatus of the present invention.
It is understood that the polishing can be performed under the condition where the shear stress that damages a is less than the fracture limit. The torque when the polishing pad is not loaded is the torque when the polishing pad 20 is rotated in a state where the polishing pad 20 and the wafer 11 are not in contact with each other.

Wafer rotation speed: n = 10 [rpm] Wafer diameter: 200 [mm] Wafer area: S = 314 [cm ² ] Polishing pad rotation speed: N = 60 [rpm] Polishing pad diameter: 500 [mm] Polishing Pad material: Polyurethane foam Hardness of polyurethane foam (Young's modulus): 0.02 to 0.10 [GPa] Wafer rotation axis radius: D = 350 [mm] Torque during no-load rotation of polishing pad: Tf = 400 [kg
・ Cm]

When the shearing stress (ft) when the torque of the polishing pad 20 is set to T = 500 [kg · cm] is calculated based on the values of these parameters, the following values are obtained.

Ft = (T−Tf) / D / S = (500−400) [kg · cm] / 350 [mm] / 314 [cm ² ] = 200 [g · cm ² ]

Here, the surface to be polished 11a and the polishing pad 20.
The coefficient of friction μ between and fluctuates, and the ratio of the vertical stress (fn) acting in the normal direction of the surface 11a to be polished and the shear stress (ft) is in the range of fn / ft = 0.2 to 0.5. The vertical stress (fn) is fn = 40 to 100
Within the range of [g / cm ² ], L such as porous silica
It is possible to suppress the shear stress to 140 [g · cm ² ] or less, which is the breaking limit of the ow-k film. Polishing pad 2
By controlling the pressing force of the wafer 11 based on the torque of 0, the surface 11 to be polished can be flattened without damaging the wafer 11.

Further, the structure in the vicinity of the polishing pad 20 will be described in detail with reference to FIGS. 2 and 3. Figure 2
(A) is a figure explaining the whole structure of polishing pad 20, (b) is an enlarged view which expanded and showed the surface of polishing pad 20. As shown in FIG. 2A, the polishing pad 2 is provided between the circular wafer edge sliding rings 25a and 25b.
0 is fixed, and the displacement of the polishing pad 20 in the radial direction is prevented. The width of the polishing pad 20 in the radial direction is set to be approximately the same as the diameter of the wafer 11 to be polished, and the surface to be polished 11a (not shown) can be collectively polished because it is on the back surface side in the drawing. Further, the polishing pad 20 rotates about the rotation axis 31 of the polishing pad, and the wafer 11 also rotates about the rotation axis.
The surface 11a to be polished can be efficiently polished by the rotation of the wafer 11 and the wafer 11.

Further, in particular, when the polishing pad 20 is formed of a material that does not impregnate the electrolytic solution that also functions as a slurry for polishing, the slurry is formed so that both surfaces of the polishing pad 20 communicate with the entire surface of the polishing pad. A supply hole 26 is formed. As shown in FIG. 6B, the surface 11a to be polished is so arranged that the electrolytic polishing and the mechanical polishing can be efficiently performed.
Is formed so that the total area of the opening of the slurry supply hole 26 facing the above-mentioned surface has a required value. In addition, the slurry supply hole 26
In order to uniformly polish the entire surface 11a to be polished, the vertical and horizontal intervals are constant over the entire polishing pad 20, but the arrangement pattern of the slurry supply holes 26 is limited to the arrangement pattern of this example. It may be formed on the concentric circles of the polishing pad 20 instead of the one. Therefore, surface plate 2
The slurry supplied from the first side is also the electrolytic solution 23 that is fluidized in the radial direction along the periphery from the center of the wafer 11 by the rotation of the wafer 11 and comes into contact with the surface 11a to be polished. Flows in a reduced state. Therefore, the current density distribution in the surface to be polished rarely varies due to the variation in the distribution of the components of the electrolytic solution, and the entire surface 11a to be polished is electropolished uniformly and mechanically polished.

Further, FIG. 2B is an enlarged view of the surface of the polishing pad 20 of FIG. 1A, and the slurry supply holes 26 are arranged in rows in the plane of the polishing pad 20 in the vertical and horizontal directions in the drawing. In addition to being formed in a shape, it is formed on the entire polishing pad 20. At this time, the diameter of the opening of the slurry supply hole 26 is formed to a value that enables efficient electrolytic polishing and mechanical polishing.

FIG. 3 is a cross-sectional structural view near the polishing pad 20. As shown in FIG. 3A, a polishing pad rotation shaft 31 is connected to the center of an electrode 22 that functions as a cathode facing the wafer 11, and the electrode 22 is mounted on a surface plate 21 so that the entire upper surface of the electrode 22 is covered. It is fixed. A conductive material such as platinum or copper can be used as a material for forming the electrode 22, and the shape of the electrode 22 may be formed according to the shape of the wafer 11, and is, for example, a disk shape. Further, the polishing pad 20 is arranged on the surface plate 21, and the polishing pad 20 rotates to rotate the polishing pad 20 to polish the wafer 11. Further, the polishing pad 20 includes the wafer edge sliding rings 25a and 25b.
Is fixed in the radial direction. Further, the wafer edge sliding rings 25a and 25b are connected to the anode of the external power source, and the wafer edge sliding rings 25a and 25b come into contact with the metal film formed on the polished surface 11a of the wafer 11 so that the metal film becomes an anode. It is said that A conductive material such as graphite, a sintered copper alloy, a sintered silver alloy, platinum, or copper can be used as a material for forming the wafer edge sliding rings 25a and 25b.

The wafer 11 is fixed to a wafer chuck 12 connected to a wafer rotation shaft 13, and the surface 11a of the wafer 11 is pressed against the polishing pad 20 while the wafer 11 rotates to rotate the surface to be polished. 11a is polished and flattened. Therefore, the cathode 22 and the surface plate 21
The electrode pad 20 is dipped in the electrolytic solution 23 filled in the electrolytic solution tank 24, and the wafer 11 also has the electrolytic solution 23.
Then, mechanical polishing is performed by the polishing pad 20, and electrolytic polishing by electrolytic action is performed.
When performing electrolytic polishing, for example, a voltage of about 1 to 3 V is applied between the surface 11a to be polished and the electrode 22, and the current density of the current flowing between the surface 111a to be polished and the electrode 22 is 1 to 50 mA / It is about cm ² . Further, the current passed between the surface 11a to be polished and the electrode 22 is not limited to direct current, and the ON / OFF switching time is 10 to 100.
A rectangular wave DC pulse of about 10 ms to 1000 ms may be used.

Further, FIG. 3B is an enlarged view in which the vicinity of the edge of the wafer 11 is enlarged. An electrode 22 serving as a cathode is arranged on the surface plate 21, and the polishing pad 20 is fixed on the electrode 22 via a pad supporting net 27. Pad support net 2
An electrolytic solution 23 is interposed between 7 and the electrode 22. The pad support net 27 has a structure that supports the polishing pad 20 and has a net shape so that the electrolytic solution 23 can pass therethrough, and can supply the electrolytic solution 23 to the polishing pad 20. The polishing pad 20 has a slurry supply hole 26 that communicates from the pad support net 27 to the surface in contact with the metal film 28 formed on the wafer 11, and the slurry supply hole 26 is formed on the surface of the metal film 28 that is the surface to be polished on the surface of the wafer 11. The electrolytic solution 23 that also functions as a slurry is supplied. Also,
The wafer 11 is fixed to the wafer chuck 12 via a wafer backing material 29. Since the wafer 11 is connected to an external power source by coming into contact with the wafer edge sliding rings 25a and 25b, the metal film 28 serves as an anode and is electrolytically polished. Then, the excess metal film 28 is removed and the surface of the metal film 28 is flattened to form wirings embedded in the grooves formed on the wafer 11.

The polishing apparatus of the present invention is not limited to the combination of mechanical polishing and electrolytic polishing, and chemical mechanical polishing (Chemical Mechanical Polishing;
It can also be used as a polishing apparatus for removing excess metal by CMP method) to form wiring. FIG. 4 shows C
It is a schematic structure figure of the polisher which polishes wafer 41 by MP method, Drawing 4 (a) is a plane structure figure and the figure (b) is a section structure figure. As shown in FIGS. 4A and 4B, the substantially circular wafer 41 is pressed against the substantially circular polishing pad 42, and the metal film serving as the wiring is polished to thereby bury the wiring embedded in the groove of the wafer 41. To form. Wafer 41
When polishing the wafer, a polishing liquid such as a slurry is supplied between the wafer 41 and the polishing pad 42, and the wafer 41 itself rotates on the wafer rotating shaft 45 while rotating.
While being pressed against, the polishing pad 42 also mechanically polishes the wafer 41 while rotating by the polishing pad rotation shaft 44. Here, the pressing force that presses the wafer 41 against the polishing pad 42 is controlled based on the torque of the polishing pad 42. Therefore, even if the insulating material forming the wafer 41 is a material having a low mechanical strength, the pressing force that presses the wafer 41 against the polishing pad 42 is controlled according to the torque of the polishing pad 42, thereby damaging the wafer 41. Mechanical polishing can be performed while applying a shearing stress that is not received to the surface to be polished of the wafer 41.

As described above, according to the polishing method and the polishing apparatus of the present invention, even if the wafer to be polished is made of a mechanically weak material, it is possible to adjust the torque of the polishing pad according to the torque of the polishing pad. By controlling the pressing force of the wafer, the excess metal film formed on the surface to be polished can be removed with almost no damage to the wafer, and the metal film embedded in the groove of the wafer is flattened. As a result, fine wiring can be formed on the wafer. Further, as compared with the conventional case where the polishing conditions are set only by the load for pressing the wafer against the polishing pad and the polishing time, it is possible to form high-quality wiring with almost no decrease in the polishing rate.

[0037]

According to the polishing method of the present invention, it is possible to control the pressing force for pressing the wafer against the polishing pad based on the torque of the polishing pad when polishing the wafer, and to directly damage the wafer. It is possible to polish the wafer so that the shear stress, which is the cause, becomes a value below the fracture limit. Furthermore, since the polishing can be performed without excessively weakening the pressing force for pressing the wafer against the polishing pad, the polishing rate is not excessively reduced. Therefore, while removing the excess metal film of the metal film embedded in the groove of the wafer, the wiring having the flattened surface is formed and the efficiency of the manufacturing process is not excessively reduced.

Further, according to the polishing apparatus of the present invention, the polishing force is not limited to the combination of the electrolytic polishing and the mechanical polishing, and the pressing force for pressing the wafer to be polished against the polishing pad is set to the torque of the polishing pad. By controlling based on this, it becomes possible to efficiently flatten the surface to be polished.

[Brief description of drawings]

FIG. 1 is a schematic configuration diagram showing a configuration of a polishing apparatus of the present invention.

2A and 2B are plan views of an example of a polishing pad used in the polishing apparatus of the present invention, FIG. 2A being an overall view and FIG.
FIG. 4 is an enlarged view of the polishing pad surface.

3A and 3B are cross-sectional structural views showing the structure of an example of a polishing pad used in the polishing apparatus of the present invention, FIG. 2A is an overall view, and FIG. 2B is an enlarged view near the edge of the polishing pad. is there.

FIG. 4 is a schematic structural view showing the structure of another example of the polishing pad used in the polishing apparatus of the present invention, FIG. 2 (a) is a plan view and FIG. 2 (b) is a sectional view.

FIG. 5 is a schematic configuration diagram of a polishing apparatus used in an experiment conducted by the inventor of the present application.

FIG. 6 is a diagram illustrating stress applied to a wafer.

[Explanation of symbols]

1 Polishing device 2 Polishing device body 3 motor driver 4 control unit 5 Operation part 10 Pressing mechanism 11, 41, 62 wafers 11a Surface to be polished 12 Wafer chuck 13, 45 Wafer rotation axis 14 Moving part 15 Laura 16 counter weight 20 electrode pads 21 surface plate 22 electrodes 23 Electrolyte 24 Electrolyte tank 25a, 25b Wafer edge sliding ring 26 Slurry supply hole 27 Pad support net 28 Metal film 29 Wafer backing material 30 Drive 31,44 Polishing pad rotation axis 32 motor 42, 61 polishing pad

   ─────────────────────────────────────────────────── ─── Continued front page    (72) Inventor Shingo Takahashi             6-735 Kita-Shinagawa, Shinagawa-ku, Tokyo Soni             -Inside the corporation (72) Inventor Naoki Komai             6-735 Kita-Shinagawa, Shinagawa-ku, Tokyo Soni             -Inside the corporation (72) Inventor Kaori Tai             6-735 Kita-Shinagawa, Shinagawa-ku, Tokyo Soni             -Inside the corporation (72) Inventor Hiroshi Horikoshi             6-735 Kita-Shinagawa, Shinagawa-ku, Tokyo Soni             -Inside the corporation (72) Inventor Hide Otorii             6-735 Kita-Shinagawa, Shinagawa-ku, Tokyo Soni             -Inside the corporation F term (reference) 3C034 AA19 CA16 CB01 DD10                 3C058 AA07 AA12 AC02 BA05 BA13                       BB02 BC02 CB02 CB03 DA13                       DA17

Claims (11)

[Claims] 1. A polishing method in which a polishing pad rotationally driven by a motor is pressed against a surface to be polished, and the surface to be polished is polished, the torque of the motor is controlled, and a stress component in an in-plane direction of the surface to be polished. The polishing method is characterized by controlling the. 2. The polishing method according to claim 1, wherein the torque is controlled to be substantially constant. 3. The polishing method according to claim 1, wherein the torque is controlled so that the stress component in the in-plane direction becomes a predetermined value or less. 4. The torque is controlled by controlling the pressing force of the polishing pad.
The polishing method described. 5. The polishing method according to claim 1, wherein electrolytic polishing is performed by interposing an electrolytic solution between the polishing pad and the surface to be polished. 6. The polishing method according to claim 1, wherein a metal film is formed on the surface to be polished. 7. The polishing method according to claim 6, wherein the material forming the metal film is copper. 8. A polishing pad for polishing a surface to be polished, a motor for rotationally driving the polishing pad, and a torque control mechanism for controlling a torque component of the motor to control a stress component in the in-plane direction of the surface to be polished. And a polishing device. 9. The torque control mechanism comprises a pressing mechanism for pressing the polishing pad against the surface to be polished by relatively moving the polishing pad in a direction perpendicular to the surface to be polished. The polishing device described. 10. The polishing apparatus according to claim 9, wherein the torque control mechanism has a pressing force control mechanism that controls the pressing force of the pressing mechanism. 11. The pressing force control mechanism corrects the pressing force according to a torque signal obtained from a motor driver that drives the motor.
No. 0 polishing apparatus.