JPH1034524A - Polishing device for cmp - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent edge sagging of the surface of a polished object caused by polishing by forming a polisher for polishing the surface of the polished object, of curved material of epoxy resin with nylon powder added thereto, and forming this polisher directly on a surface table or bonding it with a bond. SOLUTION: A polishing device for CMP(chemical mechanical polishing) ideally used for flattening polishing of a semiconductor device is provided with a polisher 1 directly formed on the upper face of a surface table 2. At the time of manufacturing this polisher 1, a resin mixture 6 obtained by adding nylon powder to a main agent and a curing agent of epoxy resin is made drip on the surface table 2 held to a polisher manufacturing tool 8. A clad sheet 9 of plane shape with a mold release agent applied thereto is fitted to the polisher manufacturing tool 8 and pressed to the resin mixture 6 from above to set the thickness of the polisher 1. After being cured by heating, the resin mixture 6 is separated from the clad sheet 9, and a groove for a polishing solution to pass is formed in the cured material to complete the polisher 1.

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 CMP suitable for use in flattening and polishing a semiconductor device in a process of manufacturing a semiconductor such as ULSI.

[0002]

2. Description of the Related Art In semiconductor device manufacturing in recent years,
The number of steps in the manufacturing process increases, and the process becomes complicated (for example, multi-layer wiring). Therefore, the shape of the surface of the semiconductor device is not always flat. For example, as shown in FIGS. 5A and 5C. It may have a convex part (step).

Further, in the manufacture of semiconductor devices, as the line width of fine processing becomes narrower, the light source wavelength of photolithography becomes shorter, and the numerical aperture (so-called NA) becomes larger.
The depth of focus for obtaining high resolution is reduced. for that reason,
The line width of fine processing in the manufacture of semiconductor devices is narrow,
As the complexity increases, the surface state of the semiconductor device is not always flat, and there are steps.

The presence of a step on the surface of a semiconductor device causes disconnection of the wiring and an increase in the local resistance value, thereby causing a disconnection or a reduction in current capacity. Further, the presence of a step in the insulating film also leads to deterioration in breakdown voltage and generation of leakage. The existence of such a step indicates that the depth of focus of the semiconductor exposure apparatus has become substantially shallow as described above. That is, when the yield and the reliability are improved and the resolution is increased, the margin of the depth of focus is reduced, so that the semiconductor device needs to be flattened.

Specifically, in a semiconductor manufacturing process, for example, a flattening technique as shown in FIG. 5 is required. Here, FIG. 5A shows an example in which an insulating film (for example, a film such as BPSG or TEOS-SiO ₂ ) formed on a semiconductor device is flattened to flatten an interlayer film. FIG. 5 shows an example of flattening a contact hole by flattening a metal (W, Al, Cu, etc.) film formed on a semiconductor device.
(C) shows the metal (W, A) formed on the semiconductor device.
This is an example in which an embedded wiring (damascene) is formed by flattening a film (1, l, Cu, etc.).

[0006] As a method of flattening the semiconductor surface, chemical mechanical polishing (Chemical Mechanical Polishing) is used.
Or Chemical Mechanical Planarization, CM
A flattening method using the technique (abbreviated as P) is expected to be promising. FIG. 6 is an explanatory view of a conventional semiconductor polishing apparatus using the CMP technique. FIG. 6 (a) is a side view of the apparatus, and FIG.
(B) is a plan view of the device.

In this semiconductor polishing apparatus, a polishing cloth (one or two layers) 15 is adhered onto a surface plate 18 to form a polisher, and a semiconductor carrier (wafer holder) 5 is mounted on the polishing cloth 15 by a wafer carrier (wafer holder) 5. (Silicon wafer) 3 is conveyed. Then, the surface of the semiconductor substrate (silicon wafer) 3 is pressed against the polishing cloth 15 by the pressure mechanism 10, and the wafer carrier (wafer holder) 5 is rotated while the polishing plate 4 is dropped from the abrasive supply mechanism 17 and the platen 18 is rotated. Is rotated and oscillated, ie, a semiconductor substrate (silicon wafer)
3. The semiconductor surface is polished by rotating and oscillating motion of 3.

As the polishing cloth 15, the lower side is a nonwoven fabric,
A felt-like sheet having a two-layer structure made of foamed polyurethane having a fine pore on the upper side is often used. In a conventional semiconductor polishing apparatus using the CMP technique, the method of detecting the amount of polishing on the surface of the semiconductor substrate 3 or the end point of polishing during polishing is controlled by controlling the polishing time and changing by the material to be polished. The rotational torque of the wafer carrier to be detected by a current value or the like, to detect a change in sound due to friction from the surface being polished, to make a hole in the surface plate 18 and the polishing cloth 15 and to pass laser light through this hole. A detection method is used, for example, by irradiating the surface of the substrate 3 and measuring the reflected light.

[0009]

However, in the CMP polishing by the conventional semiconductor polishing apparatus using the felt-like polisher, (1) the edge of the semiconductor surface by polishing is large, and (2) when a load is applied. The polisher is apt to undergo compression deformation. (3) When attaching a polishing cloth to the polishing platen,
Unevenness is likely to occur in the adhesive layer, and it is difficult to obtain high flatness.
(4) There is a problem that dressing (sharpening) is necessary because the polisher is liable to be clogged, and (5) it is difficult to obtain a surface accuracy of the workpiece to be polished below λ.

Further, among the methods for detecting the polishing amount and the polishing end point of the surface of the semiconductor substrate 3 during polishing, there is a problem that the detection accuracy is not good at present, or the polishing amount detection and the polishing end point In order to detect optically,
There is a problem that it is necessary to make a hole in the surface plate 18 and the polishing pad 15, and the detection target position is limited to the vicinity of the hole.

The present invention has been made in view of such a problem. Polished object (eg semiconductor)
1. Edge dripping of the surface can be prevented or suppressed; 2. The polisher hardly undergoes compression deformation even when a load is applied. 4. Poor flatness due to joining of the polisher and the polishing plate hardly occurs. 4. No dressing of the polisher is required. 5. High surface accuracy of the object to be polished (for example, a semiconductor) of λ or less can be obtained; 6. During polishing, the amount of polishing on the surface of the object to be polished (for example, a semiconductor) and the end point of polishing can be detected with high accuracy. Since it is not necessary to make a hole in the polisher when optically detecting the polishing amount or the end point of polishing, it is possible to detect the polishing state without changing the polishing conditions,
In addition, a CMP having a part or all of the feature that a detection target position is not limited to a specific region (a direct observation or measurement of a surface of an object to be polished such as a semiconductor surface by light is possible).
An object of the present invention is to provide a polishing apparatus for polishing.

[0012]

Accordingly, the present invention firstly provides a CMP polishing apparatus having at least a platen and a polishing polisher provided on the platen for polishing the surface of an object to be polished. The polishing polisher is formed of a cured product of an epoxy resin to which nylon powder has been added, and the polishing polisher is directly formed on the surface plate, or is bonded by a bonding material. Polishing apparatus for CMP (Claim 1) ".

The present invention also provides a second polishing apparatus for CMP comprising at least a surface plate and a polishing polisher provided on the surface plate for polishing a surface of an object to be polished, wherein the polishing polisher is made of nylon The polishing polisher is formed of a cured product of an epoxy resin to which powder and glycerin are added, and the polishing polisher is directly formed on the surface plate or bonded by a bonding material.
Polishing apparatus (Claim 2) ".

[0014] The present invention also provides a third aspect of the present invention wherein the surface plate is formed of an opaque material and emits light from an end surface of the polishing polisher toward an end surface of the polishing polisher; A light receiving unit for detecting reflected light from the surface of the object to be polished and taken out, and confirming a polishing state of the surface of the object to be polished based on a change in the reflected light detected by the light receiving unit, and a polishing end point. The polishing monitor for detecting CMP is provided, and a polishing apparatus for CMP according to claim 1 or 2 is provided.

[0015] The present invention also provides a fourth aspect of the present invention wherein the surface plate is formed of a transparent material, and a light-emitting portion for emitting light from one surface side of the surface plate toward the surface plate and the polishing polisher; A light receiving unit for detecting reflected light from the surface of the object to be polished taken out through the polishing polisher and the surface plate; and polishing the surface of the object to be polished based on a change in the reflected light detected by the light receiving unit. 2. A polishing monitor for checking a state and detecting a polishing end point is provided.
Or a polishing apparatus for CMP according to (2) (claim 4).

[0016]

BEST MODE FOR CARRYING OUT THE INVENTION A polishing apparatus for a CMP according to the present invention (claims 1 to 4), comprising at least a surface plate and a polishing polisher provided on the surface plate for polishing the surface of an object to be polished. In the above method, the polishing polisher is formed of a cured product of an epoxy resin to which nylon powder has been added, and the polishing polisher is directly formed on the surface plate or is joined by a bonding material.

Therefore, the CMP polishing apparatus according to the present invention (claims 1 to 4) has the following features. 1. The edge of the surface of the object to be polished (for example, a semiconductor) due to polishing can be prevented or suppressed.
Even if a load is applied, the polisher is unlikely to undergo compressive deformation,
3. 4. Poor flatness due to joining of the polisher and the polishing plate hardly occurs. 4. No dressing of the polisher is required. 6. High surface accuracy of the object to be polished of not more than λ can be obtained; Since it is not necessary to make holes in the polisher when optically detecting the amount of polishing or the end point of polishing,
It is possible to detect a polishing state without changing polishing conditions, and it is possible to obtain an effect that a detection target position is not limited to a specific region.

First, C according to the present invention (claims 1 to 4)
In the MP polishing apparatus, the polishing polisher is formed of a cured product of an epoxy resin to which nylon powder is added, so that the polishing polisher required for polishing an object to be polished (eg, a semiconductor) has sufficient hardness (or viscoelasticity). It is possible to secure the hardness (and the viscoelasticity) of the polishing polisher for a long time.

Therefore, if a polishing polisher suitable for not only normal polishing but also polishing under high-speed and high-pressure conditions is formed from a cured product of epoxy resin to which nylon powder is added and polishing is performed, high polishing with little edge droop can be obtained. A highly polished object (for example, a semiconductor) surface can be stably obtained over a long period of time. That is, the CM according to the present invention (claims 1 to 4)
The polishing apparatus for P includes: 1. The edge of the surface of the object to be polished (for example, a semiconductor) due to polishing can be prevented or suppressed. This has the effect that the polisher is less likely to undergo compressive deformation even when a load is applied.

In the polishing apparatus for CMP according to the present invention (claims 1 to 4), since the epoxy resin, which is a main component of the polishing polisher, has adhesiveness, the polishing polisher is formed on the surface plate. The surface plate and polishing polisher can be directly joined. For this reason, the polishing apparatus for CMP according to the present invention (claims 1 to 4) has the problem of poor flatness of the polisher surface due to uneven thickness of the bonding layer when the polishing polisher and the surface plate are bonded via an adhesive. Less likely to cause problems.

Further, in the polishing apparatus for CMP according to the present invention (claims 1 to 4), a polishing polisher can be bonded on the surface plate using a bonding material. As such a bonding material, for example,
Various adhesives such as a rubber-based adhesive and a cyanoacrylate-based adhesive, and a tape-shaped joining member such as a double-sided tape can be used. When a polishing polisher is bonded to the surface plate using a bonding material, the polishing polisher after bonding is subjected to precision processing to improve the flatness defect of the polisher surface due to uneven thickness of the bonding layer. And good flatness can be obtained.

That is, C according to the present invention (claims 1 to 4)
The polishing apparatus for MP is as follows. This has the effect that flatness defects associated with the joining of the polisher and the polishing plate are unlikely to occur.
Further, in the polishing apparatus for CMP of the present invention (claims 1 to 4), since the polishing polisher is a cured product of an epoxy resin to which nylon powder is added, there is an effect that dressing (sharpening) of the polisher is unnecessary. To play.

The epoxy resin has a small curing shrinkage,
Since the transferability with the mold for curing molding is excellent, and the cutting property of the cured product is excellent, the polished surface of the polishing polisher made of the cured product can be formed with high precision. Since the polishing surface precision of the polishing polisher is directly related to the polishing precision of the sample to be polished (semiconductor substrate), it is preferable to be as high as possible.

Therefore, the present invention using such a polishing polisher having a polishing surface formed with high precision (claims 1 to 4)
4) CMP polishing apparatus There is an effect that the surface accuracy of the object to be polished (for example, a semiconductor) having a value of λ or less can be obtained. Further, since the cured material constituting the polishing polisher is transparent, the CM according to the present invention (claims 1 to 4) may be used.
The polishing apparatus for P is as follows. When optically detecting the amount of polishing or the end point of polishing, it is not necessary to make a hole in the polisher, it is possible to detect the polishing state without changing the polishing conditions, and the detection target position is specified area. Not limited to
This has the effect.

Further, according to the present invention (claims 1 to 4),
7. The MP polishing apparatus has a polishing polisher made of a cured epoxy resin to which nylon powder (having excellent properties such as heat resistance, thermal shock resistance, and lubricity) is added. The heat distortion temperature of the polishing polisher increases,
9. An effect is also obtained that generation of frictional heat during polishing of the object to be polished (for example, a semiconductor) can be suppressed.

The epoxy resin has mechanical strength characteristics,
Since it has excellent characteristics in resistance to chemicals, a polishing polisher formed using this epoxy resin also has the same excellent characteristics. Polishing polisher according to the polishing apparatus for CMP of the present invention, not only nylon powder,
Further, it is preferably formed of a cured epoxy resin to which glycerin has been added (claim 2).

When glycerin (having excellent properties as a desiccant and a lubricant) is further added to the epoxy resin, the curing shrinkage of the epoxy resin is further reduced, so that the transferability with a mold for curing molding is improved, and the curing property is improved. 8. The property that the hardness (or viscoelasticity) of the product can be stably maintained for a long time and the cutability of the cured product are further improved; This produces an effect that generation of frictional heat during polishing of a workpiece (for example, a semiconductor) can be suppressed.

When the surface plate of the polishing apparatus for CMP according to the present invention is formed of an opaque material (for example, cast iron, zeolite, or the like), light is directed from the end face of the polishing polisher to the end face of the polishing polisher. A light emitting unit that emits light,
A light receiving unit for detecting light reflected from the surface of the object to be polished (for example, a semiconductor) taken out through the polishing polisher;
It is preferable that a polishing monitor unit is provided for checking a polishing state of the surface of the object to be polished (for example, a semiconductor) based on a change in reflected light detected by the light receiving unit and detecting a polishing end point. 3).

Further, the platen of the CMP polishing apparatus according to the present invention is formed of a transparent material (for example, fused quartz) (when the polishing polisher is bonded on the platen using a bonding material, In the case where the bonding material is also formed of a transparent material), a light emitting unit that emits light from one surface side of the surface plate toward the surface plate and the polishing polisher,
A light-receiving unit for detecting light reflected from the surface of the object to be polished (for example, a semiconductor) taken out through the polishing polisher and the surface plate; and a light-receiving unit based on a change in reflected light detected by the light-receiving unit. It is preferable that a polishing monitor for checking the polishing state of the surface of the polished object (for example, a semiconductor) and detecting the polishing end point is provided (claim 4).

With this configuration, the polishing apparatus for CMP according to the present invention (claims 3 and 4) has the following features. During the polishing, the polishing amount and the polishing end point on the surface of the object to be polished (for example, a semiconductor) can be detected with high accuracy. Also,
When the surface plate is formed of a transparent material (when the polishing polisher is bonded on the surface plate using a bonding material, the bonding material is also formed of a transparent material) (claim 4). Direct observation and measurement by light of the entire surface of the object to be polished (for example, a semiconductor) during polishing can be performed.

That is, C according to the present invention (claims 3 and 4)
According to the MP polishing apparatus, the surface state of the object to be polished (eg, a semiconductor) can be easily observed or measured from the polisher side during polishing, and the amount to be polished can be easily managed optically. FIG. 1 is a schematic diagram showing a partial configuration of a polishing apparatus (one example) for CMP of the present invention. FIG. 1 (a) is a side view, and FIG. 1 (b) is a plan view.

The polishing apparatus for CMP shown in FIG. 1 includes a polishing table 1, a polishing polisher 1 directly formed on the upper surface of the polishing table 2, which is made of a cured epoxy resin to which nylon powder is added, and a polishing object (wafer) 3. , A polishing agent supply mechanism 17 for supplying the polishing agent 4, and a pressure applying mechanism 10 for applying a pressure to an object to be polished (wafer). FIG. 2 is a process chart showing a method of manufacturing the polishing polisher 1.

First, an appropriate amount of the epoxy resin base material and the curing agent is collected, and nylon powder is added thereto, and the mixture is sufficiently stirred with a stirring bar 7 or the like (FIG. 2 (a)). A resin mixture 6 composed of a curing agent and nylon powder is dropped on the surface plate 2 held by a polisher making tool 8. In addition, glycerin may be further added to the epoxy resin.

Next, a flat plate 9 coated with a release agent is mounted on a polisher making tool 8 and pressed against the resin mixture 6 from above (FIG. 2 (c)). The thickness of the polishing polisher to be manufactured is set to a predetermined value by adjusting the position (additional pressure) of the matching plate at this time. Here, the polisher making tool 8 and the combination plate 9 provided with the pressure applying mechanism correspond to a mold for curing and molding the resin mixture 6.

Next, they are placed in a thermostat and heated and cured at a constant temperature (FIG. 2D). After the temperature is lowered to room temperature, the cured product of the resin mixture 6 is peeled off from the combination dish 9 (FIG. 2E). Then, a groove through which the polishing liquid passes is formed in the cured product (FIG. 2F) to complete the polishing polisher. The surface accuracy of the polishing polisher, which is directly related to the polishing accuracy of the work, can be obtained by using a high-precision lathe with a grinding machine, a method of grinding these plates with a high-precision lathe, a method of grinding these replicas with a high-precision lathe. Method by precision cutting,
It may be performed by any of the above.

The hardness of the polishing polisher can be set by adjusting the mixing ratio of the resin mixture, the curing conditions of the resin mixture, and the like according to the material of the object to be polished. Hereinafter, the present invention will be described in more detail with reference to examples, but the present invention is not limited to these examples.

[0037]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A polishing polisher for CMP is manufactured in accordance with the above-described manufacturing process, and this polishing polisher is subjected to high-precision high-speed
An example in which the present invention is applied to a flattening machine (a polishing apparatus for CMP) and an example in which the end point of polishing is detected by using a transparent polishing polisher will be described. Example 1 FIG. 2 shows a polishing polisher for CMP which is a cured product obtained by heating and curing a resin mixture composed of Bond Quick # 5 (epoxy resin polythiol, manufactured by Konishi), an epoxy resin adhesive, and glycerin and nylon powder. It was manufactured according to the manufacturing process described above.

First, the mixing ratio (weight ratio) of the resin mixture 6 consisting of the main component of Bond Quick # 5, a curing agent, glycerin and nylon powder (Toray Nylon Powder SP-500) is 3: 1: 1: 0.05. Then, the mixture was collected in a container and sufficiently stirred with a stirring rod 7 (FIG. 2A). The resin mixture 6 was dropped onto a flat platen 2 (made of cast iron or fused quartz, etc.) having a diameter φ: 300 mm held by a polisher manufacturing tool 8 (FIG. 2B).

Next, a flat matching plate 9 (made of cast iron, having the same diameter as the surface plate 2) coated with a release agent is attached to the production tool 8, and this is added to the resin mixture 6 on the surface plate 2 from above. Adjust the position while pressing to make the layer thickness of the resin mixture 6 3 mm
(FIG. 2C). Subsequently, the resin mixture 6 was placed in a thermostat while being held at a layer thickness of 3 mm, and heated at 70 ° C. for 1 hour to cure the resin mixture 6 (FIG. 2D). . Then, after the temperature is sufficiently lowered, the cured product of the resin mixture 6 is peeled from the combination dish 9 (FIG. 2E), and radial grooves through which the polishing liquid passes are formed in the cured product by cutting (FIG. 2E). 2 (f)) A polishing polisher was used.

The polishing polisher was surfaced using an Oscar-type polishing machine and a flat plate having a diameter of 300 mm and a 5%
(% By weight) of a cerium oxide polishing liquid. The finished surface of the polishing polisher had a surface roughness of about 1 μm. Note that the cured product of the resin mixture 6 may not be directly formed on the surface plate 2 but may be bonded to the surface plate using a rubber adhesive, a cyanoacrylate adhesive, or a double-sided tape to form a polishing polisher. .

In this case, polishing of the polishing polisher is performed by cutting with an ultraprecision lathe, and the finished surface of the polishing polisher can have a surface roughness of 1 μm or less. Next, CMP using the polishing polisher manufactured as described above
A polishing process for flattening a semiconductor by a polishing apparatus for polishing (see FIG. 1) will be described. The wafer to be polished is a Si wafer having a diameter of 3 inches and a thickness of 25 μm.
forming a silicon oxide film (SiO ₂ ) by CVD with a thickness of m
A pattern was formed by photolithography.

Further, a 1 μm aluminum layer was formed thereon to prepare a sample having the sectional structure shown in FIG. 5B. The pattern surface of this sample (wafer) was polished under the following conditions. Processing conditions ・ Spindle (work) rotation speed: 250 rpm ・ Swing distance of carrier (holder) to be polished: 15 mm ・ Number of swings of carrier (holder) to be polished: 45 reciprocations /
Min. ・ Additional load by pressure application mechanism: 190 g / cm ²・ Polishing liquid (agent): 6% concentration of cerium oxide (automatic supply) ・ Polishing time: 1 minute Under these polishing conditions, 130 samples (wafers) are continuously formed When polished, Newton stripes 2-4
A book plane was obtained. In addition, the influence of the flatness and the edge droop due to the pattern density was not observed.

When inspecting the polished surface after polishing,
Dressing was unnecessary because it had not changed from the initial state. In the conventional method using a polishing cloth, dressing was necessary, but there was no problem particularly with the present polisher. "Example 2" A cured product obtained by heat-curing a resin mixture of Bond Quick # 5 used in Example 1, a resin mixture of tetraethylenepentamine as a curing agent, glycerin, and nylon powder (SP-500 manufactured by Toray). Some CMP
A polishing polisher was manufactured according to the process shown in FIG.

The mixing ratio (weight ratio) of the resin mixture consisting of the main component of BondQuick, tetraethylenepentamine, glycerin, and nylon powder was 3: 1: 0.5: 0.05. The subsequent steps are the same as in the first embodiment. However, the grooves of the polishing polisher were spiral. Using a polishing apparatus for polishing using the polishing polisher manufactured as described above, 130 samples of the same type as in Example 1 were continuously processed under the same conditions as in Example 1. As a result, 2 to 4 Newton stripes and a flatness λ (rms) were obtained.
Accuracy was obtained. The surface roughness was 3 to 7 A by RMS.

When the polished surface after polishing was inspected,
Dressing was unnecessary because it had not changed from the initial state. Example 3 The same polishing polisher as in Example 1 was formed on a plate made of cast iron. In the manufacture of the polishing polisher, a matching plate method was employed as in the polisher manufacturing method described in the above embodiment.

The same semiconductor surface polishing as in Example 1 was performed by a CMP polishing apparatus using the manufactured polishing polisher together with end point detection using light. As a result of continuous processing, the accuracy of 2 to 4 Newton stripes and flatness λ (rms) is obtained.
The surface roughness was 3-9A by RMS. Inspection of the polished surface after polishing showed that the dressing was not necessary since it had not changed from the initial state.

The observation system for the surface of the object to be polished (semiconductor) was configured as shown in FIG. Laser light source 11 as light emitting unit
A detector (light receiving portion) 12 disposed opposite to the light source with a polishing polisher interposed therebetween is fixed to the surface plate 2, and has a structure that rotates with the rotation of the surface plate 2.
In addition, the polishing monitor section 16 has a function of confirming the polishing state of the surface of the object to be polished (semiconductor) based on a change in the amount of light detected by the detector 12 and detecting the polishing end point.

According to the observation system for the surface of the object to be polished (semiconductor),
The polishing state of the semiconductor surface during polishing can be confirmed as follows. When a transparent polishing polisher (mixed epoxy resin layer) is used like a waveguide by obliquely inputting a laser beam from a laser light source 11 from the end face side of the polishing polisher 1 in the observation system, the aluminum layer on the semiconductor surface is entirely covered. The amount of light entering the detector 12 decreases as the polishing state changes from the remaining state, and at the polishing end point where the aluminum layer to be polished disappears, a change in reflected light rapidly occurs. Check
Also, the polishing end point can be detected.

As described above, according to the polishing apparatus for CMP of this embodiment, the surface condition of the object to be polished (semiconductor) can be easily observed or measured from the end face side of the polisher during polishing.
The amount to be polished can be easily controlled optically. "Example 4" In the above example, the surface plate was made of an opaque material, whereas in the present example, the surface plate 13 was made of transparent fused quartz, and an epoxy A mixture of resin, glycerin and nylon powder was cured to form a polishing polisher.

Then, the polishing polisher is subjected to grooving by grinding and surfacing by polishing in the same manner as in the first embodiment, and the same polishing of the semiconductor surface as in the first embodiment by the polishing apparatus for CMP using the polishing polisher is performed. This was performed together with the end point detection using. The result of continuous processing is 2 to 4 Newton stripes,
The accuracy of flatness λ (rms) was obtained, and the surface roughness was 3 to 9 A in RMS. Inspection of the polished surface after polishing showed that the dressing was not necessary since it had not changed from the initial state.

The observation system for the surface of the object to be polished (semiconductor) was configured as shown in FIG. A laser light source 11 which is a light emitting unit and a detector 12 which is a light receiving unit are made of a platen 13 made of fused silica.
It is arranged below. Also, the polishing monitor 16
Has a function of confirming the polishing state of the surface of the object to be polished (semiconductor) based on a change in the amount of light detected by the detector 12 and detecting the polishing end point.

The observation system for the surface of the object (semiconductor) to be polished
The polishing state of the object to be polished (semiconductor) during polishing can be confirmed as follows. When the laser light from the laser light source 11 is introduced from obliquely downward or downward toward the transparent surface plate 13, the polishing polisher 1, and the surface of the workpiece (semiconductor) 3, the reflected light from the surface of the workpiece (semiconductor) 3 Is guided to the detector 12 through the partial reflection mirror 14, so that direct observation or measurement of the entire surface of the object to be polished (semiconductor) 3 by light is possible.

At this time, the amount of light entering the detector 12 decreases as the aluminum layer on the semiconductor surface is polished from the state in which the aluminum layer remains on the entire surface, and the reflected light changes at the polishing end point when the aluminum layer to be polished is gone. Suddenly, the polishing monitor unit 16 confirms the polishing state from now on,
Also, the polishing end point can be detected. In the state where the aluminum layer to be polished is gone, the reflected light suddenly decreases and the reflected light starts to fluctuate so as to vibrate. Thus, the polishing monitor 16 can detect the polishing end point.

As described above, according to the polishing apparatus for CMP of this embodiment, the surface state of the object to be polished (semiconductor) can be easily observed or measured from the polisher side during polishing, and the amount to be polished can be determined optically. Can be easily managed.

[0055]

As described above, the present invention (Claim 1)
According to the polishing apparatus for CMP of 4) to 4), 1. The edge of the surface of the object to be polished (for example, a semiconductor) due to polishing can be prevented or suppressed. 2. The polisher hardly undergoes compression deformation even when a load is applied. 4. Poor flatness due to joining of the polisher and the polishing plate hardly occurs. 4. No dressing of the polisher is required. 5. High surface accuracy of the object to be polished (for example, a semiconductor) of λ or less can be obtained; 6. During polishing, the amount of polishing on the surface of the object to be polished (for example, a semiconductor) and the end point of polishing can be detected with high accuracy. It is not necessary to make holes in the polisher when optically detecting the amount of polishing or the end point of polishing, so it is possible to detect the polishing state without changing the polishing conditions, and specify the target position for detection. 7. It is not limited to a region (direct observation or measurement by light on the surface of the object to be polished is possible). 8. the heat distortion temperature of the polishing polisher is increased; Some or all of the effects of being able to suppress the generation of frictional heat during polishing of the object to be polished (for example, a semiconductor) are exhibited.

According to the polishing apparatus for CMP of the present invention (claims 1 to 4), dressing is not required unlike a conventional polishing cloth, and polisher hardness (or viscoelasticity) can be kept constant for a long period of time. Since it is possible, once the surface accuracy of the polishing polisher has been obtained, subsequent surface accuracy adjustment is unnecessary. If the surface of the same type of object to be polished (eg, a semiconductor) is to be flattened, the polishing polisher is replaced or adjusted. Polishing can be performed many times without the need for polishing.

Therefore, the time required for the replacement operation of the polishing polisher can be reduced, and the downtime of the apparatus can be reduced.
In addition, a high-precision object to be polished (for example, a semiconductor) having a high surface accuracy and a small edge is eliminated while eliminating polishing skill.
It goes without saying that the surface can be flattened continuously in a short time. In addition, C of the present invention (claims 3 and 4)
According to the MP polishing apparatus, in confirming the state of the surface of the object to be polished (for example, a semiconductor) during polishing and detecting the polishing end point, the accuracy is higher than the conventional method using indirect information (sound, heat, etc.). There is an advantage that a system according to an optical observation method capable of confirmation and detection can be more easily adopted.

[Brief description of the drawings]

FIG. 1 is a schematic view showing a partial configuration of a polishing apparatus (one example) for CMP of the present invention. FIG. 1 (a) is a side view, and FIG.
(B) is a plan view.

FIG. 2 is a process chart showing a method of manufacturing a polishing polisher.

FIG. 3 is a side view illustrating an example of an optical measurement technique according to a third embodiment.

FIG. 4 is a side view illustrating an example of an optical measurement method according to a fourth embodiment.

FIG. 5 is a diagram showing an example of a cross-sectional structure of a semiconductor device which is one of the objects to be polished by the CMP polishing apparatus according to the present invention.

FIG. 6 is a schematic view showing a partial configuration of a conventional CMP polishing apparatus (one example), FIG. 1 (a) is a side view, and FIG. 1 (b).
Is a plan view.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Polishing polisher (for example, nylon epoxy polisher) 2 ... Surface plate 3 ... Wafer (an example of an object to be polished) 4 ... Abrasive agent 5 ... Wafer holder and carrier (holder of object to be polished) 6) Resin mixture (e.g. epoxy resin base and curing agent, glycerin, nylon powder) 7 ... Stirrer bar 8 ... Polisher manufacturing tool 9 ... Matching plate 10 ... Pressure applying mechanism DESCRIPTION OF SYMBOLS 11 ... Laser light source (light emitting part) 12 ... Detector part (light receiving part) 13 ... Surface plate made of fused quartz 14 ... Partial reflection mirror 15 ... Polishing cloth 16 ... Polishing monitor Part 17: Abrasive supply mechanism 18: Surface plate

Claims (4)

[Claims] 1. A C comprising at least a surface plate and a polishing polisher provided on the surface plate for polishing a surface of an object to be polished.
In the polishing apparatus for MP, the polishing polisher is formed of a cured product of an epoxy resin to which nylon powder is added, and the polishing polisher is directly formed on the surface plate, or is bonded by a bonding material. Polishing apparatus for CMP. 2. A C comprising at least a surface plate and a polishing polisher provided on the surface plate for polishing a surface of an object to be polished.
In a polishing apparatus for MP, the polishing polisher is formed of a cured product of an epoxy resin to which nylon powder and glycerin are added, and
The polishing apparatus according to claim 1, wherein the polishing polisher is directly formed on the surface plate or is bonded by a bonding material. 3. The platen is formed of an opaque material,
A light emitting unit that emits light from the end surface side of the polishing polisher toward the end surface of the polishing polisher, a light receiving unit that detects reflected light from the surface of the object to be polished extracted through the polishing polisher, 3. A polishing monitor unit for confirming a polishing state of the surface of the object to be polished based on a change in reflected light detected by a light receiving unit and detecting a polishing end point. Polishing equipment for CMP. 4. A light emitting unit which is formed of a transparent material and emits light from one surface side of the surface plate toward the surface plate and the polishing polisher; A light-receiving unit that detects light reflected from the surface of the object to be polished taken out via the light-receiving unit, and confirms a polishing state of the surface of the object to be polished based on a change in reflected light detected by the light-receiving unit; 3. The CMP according to claim 1, further comprising a polishing monitor for detecting an end point.
Polishing equipment.