JPH11320371A - Polishing device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a polishing device to uniformly polish the whole surface of a substrate to be polished. SOLUTION: This polishing device comprises a substrate 100 to be polished held by a rotating substrate holder 12; a grinding wheel mechanism 13 be formed that a plurality of grinding wheels 14 are mounted on a rotating belt 15; and a linear movement mechanism to cause linear movement of the substrate holder 12. Simultaneously with rotation of the belt 15 with the substrate 100 to be polished brought into contact with the surface of the grinding wheel 14 of the grinding wheel mechanism 13, the substrate holder 12 is rotated and further, by effecting linear movement of the substrate holder 12, the substrate 100 to be polished is polished.

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 polishing a substrate to be polished such as a semiconductor wafer, various hard disks, a glass substrate and a liquid crystal panel.

[0002]

2. Description of the Related Art Conventionally, a CMP (Chemical Mechanical Polishing) apparatus used in a manufacturing process of a semiconductor integrated circuit device includes a substrate to be polished mounted on a rotating top ring on a polishing cloth surface stuck on a turntable. And polishing the polishing surface of the substrate to be polished (free abrasive polishing) while supplying polishing slurry onto the polishing cloth. However, in the case of this CMP apparatus, there is a problem that it cannot be sufficiently flattened depending on the type of the pattern on the polished surface and the state of the steps (irregularities).

Therefore, instead of the CMP apparatus having the above structure,
A fixed-abrasive polishing method has been developed in which a grindstone is pressed against a substrate to be polished, and a polishing liquid (solution) is supplied to the surface of the grindstone while the two are relatively moved to polish the substrate to be polished. Among such grindstones, there is a cup-shaped grindstone having a structure in which a pellet-shaped grindstone is attached to a grindstone support member in a ring shape.

[0004]

However, in the polishing of a substrate to be polished with a pellet-type grindstone, it is difficult to uniformly polish the substrate to be polished over its entire surface. It has also been difficult to arbitrarily adjust the amount of polishing in each part of the substrate to be polished and correct it.

[0005] In addition, in the polishing with a grindstone, since the grindstone itself is worn, it is necessary to appropriately replace the grindstone, which is complicated.

The present invention has been made in view of the above points, and an object of the present invention is to provide a polishing apparatus capable of uniformly polishing the entire surface of a substrate to be polished.

Another object of the present invention is to provide a polishing apparatus which can easily correct even if the polishing amount becomes non-uniform.

[0008] Another object of the present invention is to provide a polishing apparatus which can eliminate the necessity of replacing a grindstone.

[0009]

In order to solve the above-mentioned problems, a polishing apparatus according to the present invention comprises a substrate to be polished held by a rotating substrate holder and a plurality of grindstones attached to or rotated by a rotating belt. A whetstone mechanism that uses the surface of the belt itself as a whetstone, and the substrate holder is moved in a direction different from the traveling direction of the belt of the whetstone mechanism, or the whetstone mechanism is moved in a direction different from the traveling direction of the belt of the whetstone mechanism. A rotation mechanism for moving the substrate holder at the same time as rotating the belt while the substrate to be polished is in contact with the surface of the grindstone of the grindstone mechanism, and further moving the substrate holder and / or the grindstone mechanism to the movement mechanism. The substrate to be polished is polished by moving the substrate. It is preferable that the grindstone mechanism is provided with one or more pressing means for pressing the belt of the grindstone mechanism from the inside toward the substrate to be polished. A grindstone mechanism that uses the rotating belt surface itself as a grindstone has a grindstone material application unit that applies a grindstone material having a predetermined thickness to the rotating belt surface, and a grindstone material drying unit that dries the applied grindstone material. It is preferable to provide a grindstone generation mechanism configured to include: Further, the polishing apparatus according to the present invention, a substrate to be polished held by a rotating substrate holder, a grinding wheel attached to one end of the rotating belt or a grinding wheel mechanism using one end of the rotating belt itself as a grinding stone, A movement mechanism for moving the substrate holder in a direction different from the traveling direction of the belt of the grinding wheel mechanism, or a movement mechanism for moving the grinding wheel mechanism in a direction different from the traveling direction of the belt of the grinding wheel mechanism; The belt is set so that its surface is perpendicular to the substrate to be polished. Further, the substrate to be polished is polished by moving the substrate holder and / or the grindstone mechanism by the moving mechanism. The belt is wound around two belt rollers. On the other hand, a belt guide roller for maintaining the tension of the belt by pressing against the belt is installed. It is preferable to change the belt shape by adjusting the center distance between the belt rollers.

[0010]

Embodiments of the present invention will be described below in detail with reference to the drawings. FIG. 1 is an overall schematic perspective view of a polishing apparatus according to a first embodiment of the present invention. As shown in the figure, the polishing apparatus includes a substrate (semiconductor wafer) 1 to be polished.
00, a substrate holder 12, a grindstone mechanism 13 having a grindstone 14, a belt 15, and a belt roller 16, and a base 17
And a U-shaped arch 19. Hereinafter, each component will be described.

The substrate holder 12 holds the substrate 100 to be polished.
Disk-shaped holder body 12 for mounting and holding the
The supporting column 123 is configured to protrude from the center of the lower surface of the base 1, and the lower end of the supporting column 123 is provided with an engaging portion 125 that is engaged with a guide groove 171 provided in the base 17 described below. The holder main body 121 is driven to rotate by a driving mechanism (not shown) built in the support column 123.

Next, the belt 15 has two belt rollers 1.
6, a number of grinding wheels 14 are mounted on the outer surface of the wheel 6 in a row.

FIG. 2 is a view showing an example of actual attachment of the grindstone 14 to the belt 15. FIG. 2A is a plan view of a main part, and FIG. 2B is a sectional side view of the main part. FIG. 1A is a cross-sectional view taken along line AA, and FIG. 1C is a perspective view of the belt roller 16.

As shown in FIG. 1, the grindstone 14 is mounted by fastening a grindstone holder 21 holding the grindstone 14 from behind the belt 15 with bolts 23. In the center of the belt roller 16, an escape groove 161 (see FIG. 2C) for the head of the bolt 23 is provided.

The two belt rollers 16 are suspended from the arch portion 19 by an arm 25, and the belt roller 16 is configured to be rotationally driven by a driving mechanism (not shown).

When the belt roller 16 is rotated by a driving mechanism (not shown) to rotate the belt 15, the head of the bolt 23 passes through the clearance groove 161.
It does not hinder the rotation of. Further, since each of the grindstones 14 and the grindstone holder 21 is fastened to the belt 15 at only one place, the fastening state is maintained even when the grindstone 14 and the grindstone holder 21 approach the curved portion of the belt 15, and the flat surface portion , The grindstone 14 and the grindstone holder 21 are along the belt 15.

In this embodiment, the belt 15 is made of, for example, a rubber material. However, various other materials and structures, such as a metal or plastic member connected in a caterpillar shape, may be used.

Next, the base 17 is provided with a linear guide groove 171 at the center thereof. And this base 1
A drive mechanism (not shown) for driving the engagement portion 125 so as to be able to linearly move in the guide groove 171 is built in the inside of the guide groove 171.

Next, the substrate 10 to be polished is
In order to polish the substrate 0, the substrate holder 12 on which the substrate to be polished 100 is mounted is rotated, and the grindstone 14 linearly moving on the lower surface of the belt 15 rotationally driven by the belt roller 16 is rotated. 100, the substrate holder 12 is moved linearly by moving the engaging portion 125 in the guide groove 171 of the base 17, and the relative movement of these members causes the substrate 100 to be polished.
The surface is uniformly polished. The rotation speed of the outer peripheral portion of the substrate holder 12 is usually set to be higher than the moving speed of the belt 15 and the linear movement speed of the entire substrate holder 12.

In the above embodiment, the whole substrate holder 12 is linearly moved with respect to the base 17 as an example of the relative movement.
7 may be configured to perform a scrolling motion, a rotating motion, or the like. Further, instead of the substrate holder 12, the grindstone mechanism 13 may be configured to move linearly. Further, both the substrate holder 12 and the grindstone mechanism 13 may be configured to move linearly. In short, the substrate holder 12 is moved in a direction different from the rotation direction of the substrate holder 12, or the grindstone mechanism 13 is moved to the grindstone mechanism 13.
Any movement mechanism may be used as long as it can move in a direction different from the traveling direction of the belt 15. This is the same in the second, third, and fourth embodiments described below.

FIGS. 3A and 3B are views showing a main part of a second embodiment of the present invention. FIG. 3A is a side view of the main part, and FIG. 3B is a sectional view taken along line BB of FIG. It is. In the embodiment shown in the figure, the same parts as those in the first embodiment are denoted by the same reference numerals, and detailed description thereof will be omitted.

This embodiment is different from the first embodiment only in that three pressing means 31 are provided between the left and right arms 25, 25 suspended from the arch portion 19.

Each of these three pressing means 31 projects the rod 35 downward from a pressing cylinder 33 fixed to the lower surface of the arch portion 19, straddles the tip of the rod 35 and straddles the upper belt 15, A pressure roller 37 is rotatably mounted between both ends.

The belt 15 is rotated and driven in the same manner as in the first embodiment shown in FIG.
When polishing the substrate 100, the pressures of the three pressing cylinders 33 are changed as needed, so that the substrate to be polished 100
The pressing pressure of the grindstone 14 on each part of
Each of them is set to a predetermined value within the range of 600 [gf / cm ² ].

As a result, the polishing amount of the substrate to be polished 100 can be changed according to its location, and even if the polishing amount of the substrate 100 to be polished is uneven, this can be corrected.

The number of the pressing means 31 is not limited to three, but may be one or two or more. Needless to say, the shape and structure of the pressing means 31 itself can be variously modified.

FIG. 4 is a schematic side view showing a main part of a third embodiment of the present invention. That is, in the case of this embodiment, FIG.
Instead of attaching a large number of grindstones 14 to the belt 15 as in the first embodiment, an example is shown in which the surface itself of the belt 15 is configured as a grindstone. In the case of this embodiment, a grindstone generating mechanism 41 for sequentially applying and generating a grindstone material having a predetermined thickness on the surface of the rotating belt 15 is provided.

That is, the grindstone generating mechanism 41 includes a grindstone material supply means 45 for supplying a grindstone material 43 in a liquid state, and a flat cylindrical grindstone material application means 47 for applying the grindstone material 43 to the entire width of the belt 15. And a grindstone material drying means 49 comprising a dryer. Whetstone material 43
For example, a liquid phenol binder mixed with silica abrasive grains and dispersed in a volatile mixed medium (such as alcohol) is used. As the grinding wheel material drying unit 49, various other grinding wheel material drying units such as a drying unit using infrared rays using an electric heater or the like other than a dryer or a vacuum drying unit may be used.

Then, while polishing the substrate 100 to be polished by the belt 15 rotated by the belt roller 16, the grindstone material is supplied from the grindstone material supply means 45 to the grindstone material application means 47 at the same time, and the grindstone material is applied to the surface of the belt 15 by a predetermined amount. Then, the grindstone material is solidified by the grindstone material drying means 49, and a layer of grindstone is sequentially formed on the surface of the belt 15.

With this configuration, even if the grindstone is worn over time due to polishing, it is not necessary to replace the grindstone.

The structure of the grindstone generating mechanism 41 is not limited to this embodiment, but can be variously changed. In short, a grindstone material having a predetermined thickness is applied to the rotating belt surface to generate the grindstone. Any structure may be used as long as it is a whetstone generating mechanism.

FIGS. 5A and 5B are views showing a fourth embodiment of the present invention. FIG. 5A is a schematic sectional side view, and FIG. 5B is a schematic plan view (however, the pressing cylinder 79 is not shown. The support arm 83 is shown by a two-dot chain line).

The polishing apparatus according to this embodiment includes a substrate to be polished 100, a substrate holder 51, a grindstone 55 and a belt 5
And a linear motion mechanism 81 including a support arm 83 and a ball screw 85.
Is provided. Hereinafter, each component will be described.

The substrate holder 51 has a substrate 1 to be polished on its upper surface.
00 and a motor 61 installed on the lower surface thereof.
Is driven to rotate.

Next, the linear motion mechanism 81 is formed by screwing ball screws 85 to both ends of a U-shaped support arm 83, respectively. Motors 87, 87 are attached to one end of each ball screw 85.
The support arm 83 is moved in a straight line (in the direction of arrow C) by driving the actuators 7 and 87 simultaneously.

Next, the grindstone mechanism 53 has its rotating shafts 63, 6
3 faces in a direction perpendicular to the surface of the substrate 100 to be polished 2
One flat belt 5 on one belt roller 59, 59
7 and a number of pellet-like grinding wheels 55 are attached to one end of the lower side of the belt 57 in a row.
The upper portions of the rotary shafts 63 and 63 are rotatably supported by bearing mechanisms 65 and 65, and a drive motor 67 is attached to one end of one rotary shaft 63. In addition, both bearing mechanisms 65, 6
5 includes a rod 7 projecting from the center distance adjusting cylinder 69.
1 and 71 are attached, and another inter-axis distance adjusting cylinder 73 is fixed to the upper part of the inter-axis distance adjusting cylinder 69 so as to be orthogonal thereto, and rods 75 projecting from both sides of the inter-axis distance adjusting cylinder 73 are provided. 75 is bent at a right angle downward, and the belt guide roller 77,
77 is attached.

The belt guide rollers 77, 77 are located at positions where their outer peripheries just contact the side surfaces of the belt 57.

A tip of a rod 78 projecting from a lower end of the pressing cylinder 79 is fixed to an upper portion of the inter-axis distance adjusting cylinder 73. The pressing cylinder 79 includes a support arm 83
It is fixed to. That is, each member of the grindstone mechanism 53 is suspended by the pressing cylinder 79 fixed to the support arm 83.

FIG. 6 is an enlarged side sectional view showing a main part of an example of attaching the grindstone 55 to one end of the belt 57. As shown in FIG. As shown in the figure, the grindstone 55 is attached by fastening the grindstone holder 101 holding the grindstone 55 to the belt 57 with bolts 103. When the belt 57 is made of a soft material such as rubber, the grindstone holder 101 may be fastened by driving a female screw into the belt 57 and screwing the bolt 103 to the female screw.

Next, the operation of the polishing apparatus will be described. First, the substrate 61 to be polished held on the upper surface of the substrate holder 51 is rotated by driving the motor 61.

On the other hand, when the pressing cylinder 79 is pressurized, the whole grindstone mechanism 53 is moved downward, and the grindstone 55 attached to the lower end of the belt 57 is pressed by the predetermined pressure onto the substrate 1 to be polished.
The belt 55 is driven by rotating the belt rollers 59, 59 by driving the drive motor 67, and the grindstone 55 is moved while being rubbed on the substrate 100 to be polished.

At the same time, by driving the motors 87, 87, the support arm 83 is moved linearly (in the direction of arrow C), whereby the surface of the substrate 100 to be polished is uniformly polished by the relative movement of these members.

By driving the inter-axis distance adjusting cylinder 69, for example, the rotating shaft 6 of the two belt rollers 59, 59 is rotated.
If the distance between the belt guide rollers 77 and 77 is reduced by moving the inter-axis distance adjusting cylinder 73 in the direction of the arrow E, the belt is narrowed. Belt 5 while maintaining the tension of 57
7 can be changed. That is, the shape of the belt 57 can be arbitrarily adjusted by controlling the distance adjusting cylinders 69 and 73 between both shafts. Thus, for example, even when the surface of the substrate 100 is unevenly polished, the surface of the substrate 100 is locally polished by adjusting the shape of the belt 57 to a desired shape. The correction can be made so that the entire surface of the substrate to be polished 100 is polished uniformly.

In this embodiment, a large number of pellet-shaped grindstones 55 are attached to one end of the belt 57. Instead, a layer of grindstone is formed on one end of the belt 57 itself, and this is configured as a grindstone. Is also good.

In some cases, in addition to the polishing apparatus using the grindstone according to the present invention, a CMP apparatus including a polishing cloth or the like described in the section of the related art is installed.
The substrate to be polished may be polished by the CMP apparatus in the steps before and after the polishing by the polishing apparatus using the grindstone according to the present invention.

[0046]

As described in detail above, the present invention has the following excellent effects. The belt is rotated at the same time as the belt is rotated while the substrate to be polished is in contact with the surface of the grindstone attached to the belt of the grindstone mechanism, and the substrate holder and / or the grindstone mechanism is moved in a direction different from the rotation direction of the substrate holder or the grindstone. Since the substrate to be polished is polished by moving in a direction different from the traveling direction of the belt of the mechanism, the entire surface of the substrate to be polished can be uniformly polished.

Since the pressing means for pressing the belt of the grindstone mechanism from the inside toward the substrate to be polished is provided, even if the polishing amount is uneven on the surface of the substrate to be polished, it can be corrected. Can be.

Since a grindstone generating mechanism for applying and drying a grindstone material to the rotating belt surface is provided, it is not necessary to replace the grindstone.

Since the inter-axis distance between the two belt rollers wound around the belt is adjusted by the inter-axis distance adjusting means so as to change the belt shape, even if the polishing amount is uneven on the surface of the substrate to be polished. If so,
This can be corrected.

[Brief description of the drawings]

FIG. 1 is an overall schematic perspective view of a polishing apparatus according to a first embodiment of the present invention.

FIGS. 2A and 2B are views showing an example of actual mounting of the grindstone 14 to a belt 15, wherein FIG. 2A is a plan view of a main part, FIG. 2B is a sectional side view of a main part, and FIG. FIG. 3 is a perspective view of a belt roller 16.

FIG. 3 is a diagram showing a main part of a second embodiment of the present invention,
FIG. 3A is a side view of a main part, and FIG.
It is -B sectional drawing.

FIG. 4 is a schematic side view showing a main part of a third embodiment of the present invention.

FIGS. 5A and 5B are views showing a fourth embodiment of the present invention, wherein FIG. 5A is a schematic side sectional view, and FIG. 5B is a schematic plan view.

FIG. 6 is an enlarged side sectional view of a main part showing an example of attaching one of the grindstones 55 to one end side of a belt 57.

[Explanation of symbols]

 REFERENCE SIGNS LIST 100 substrate to be polished 12 substrate holder 13 grindstone mechanism 14 grindstone 15 belt 16 belt roller 17 base 171 guide groove (linear motion mechanism) 125 engaging portion (linear motion mechanism) 31 pressing means 41 grindstone generation mechanism 51 substrate holder 53 grindstone mechanism 55 grindstone 57 belt 59 belt roller 69 inter-axis distance adjusting cylinder (inter-axis distance adjusting means) 77 belt guide roller 81 linear motion mechanism

 ────────────────────────────────────────────────── ─── Continued on the front page (72) Inventor Hitoshi Hirokawa 4-2-1 Motofujisawa, Fujisawa-shi, Kanagawa Inside Ebara Research Institute, Ltd.

Claims (5)

[Claims] 1. A substrate to be polished held by a rotating substrate holder, a plurality of grinding stones attached to a rotating belt or a grinding wheel mechanism using the surface of the rotating belt itself as a grinding stone; A movement mechanism for moving the grinding wheel mechanism in a direction different from the traveling direction of the belt of the grinding wheel mechanism, or a movement mechanism for moving the grinding wheel mechanism in a direction different from the traveling direction of the belt of the grinding wheel mechanism. A polishing apparatus for polishing a substrate to be polished by rotating the substrate holder at the same time as rotating the belt in a state of being in contact with the surface, and further moving the substrate holder and / or the grindstone mechanism by the movement mechanism. 2. A belt for pressing the belt of the grindstone mechanism from the inside toward the substrate to be polished.
The polishing apparatus according to claim 1, wherein two or more pressing means are provided. 3. A whetstone mechanism for applying a whetstone material having a predetermined thickness to a surface of the rotating belt, wherein the whetstone mechanism uses the surface of the rotating belt itself as a whetstone. 3. The polishing apparatus according to claim 1, further comprising a grindstone generating mechanism configured to include a grindstone material drying unit. 4. A substrate to be polished held by a rotating substrate holder, a grinding wheel attached to one end of the rotating belt or a grinding wheel mechanism using one end of the rotating belt itself as a grinding stone. A movement mechanism for moving the grinding stone mechanism in a direction different from the traveling direction of the belt, or a movement mechanism for moving the grinding stone mechanism in a direction different from the traveling direction of the belt of the grinding stone mechanism; The substrate is set so that the surface is perpendicular to the substrate to be polished, and the belt is rotated while the grindstone at one end of the belt of the grindstone mechanism is in contact with the surface of the substrate to be polished. as well as/
Alternatively, a polishing apparatus is characterized in that a substrate to be polished is polished by moving a whetstone mechanism by the motion mechanism. 5. The belt is wound around two belt rollers. On the other hand, a belt guide roller for maintaining the tension of the belt by pressing against the belt is provided, and an inter-axis distance adjusting means is provided between the two belt rollers. 5. The polishing apparatus according to claim 4, wherein the distance between the two belt rollers is adjusted to change the shape of the belt.