JP2000271854A - Processing method and apparatus, and processing method of semiconductor substrate - Google Patents

Abstract

(57) Abstract: In a polishing such as a CMP, a processing method and an apparatus and a semiconductor substrate for uniforming a polishing rate in a surface to be processed, stabilizing an average in-plane polishing rate, and reducing scratches, and a semiconductor substrate. To provide a processing method. The present invention relates to a flatness measuring means for measuring the flatness of a polishing pad, a surface roughness measuring means for measuring a surface roughness of a polishing pad, and free abrasive grains supplied and dispersed on the surface of the polishing pad. Free abrasive grain measuring means 60 for measuring the distribution or amount of the workpiece on the processing surface with respect to, and measuring means 70 for measuring the elasticity or bubble rate of the polishing pad,
80 and a processing apparatus such as a CMP equipped with the same.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a CMP (Chemical Mecha) for supplying and dispersing free abrasive grains such as silica on a polishing pad to flatten and polish a surface of a workpiece such as a semiconductor substrate.
The present invention relates to a processing method such as polishing or grinding for embedding fixed abrasive grains such as diamond in a polishing pad, and flattening and grinding in the same manner as the polishing pad, a device therefor, and a method for processing a semiconductor substrate.

[0002]

2. Description of the Related Art Conventionally, CMP for flattening and polishing a surface of an insulating film such as a wafer by supplying and dispersing free abrasive grains such as silica on a polishing pad, or embedding fixed abrasive grains such as a diamond in a polishing pad, and flattening the same. In a polishing / grinding method (hereinafter, collectively referred to as polishing) in which chemical grinding is performed, the polishing amount (polishing rate) per unit time varies due to various factors. If the polishing rate is constant, the desired polishing amount (about 2 μm) can be processed by the polishing time obtained by the following equation (1).

Polishing time = target polishing amount / polishing rate (Equation 1) However, since the polishing rate varies every moment during polishing, time management alone was not sufficient to obtain a desired polishing amount. Then, instead of time management,
No. 113 (prior art 1), and JP-A-9-798
A technique for directly measuring the remaining film thickness during polishing, which is known from Japanese Patent Publication No. 5 (Prior Art 2), is required.

Japanese Patent Application Laid-Open No. 9-285555 (Prior Art 3) discloses measuring the amount of light reflected from the surface of a polishing pad in use in a CMP polishing process, and polishing based on the measured amount of reflected light. Calculate the polishing efficiency of the pad, evaluate the polishing performance of the polishing pad according to the change in the calculated polishing efficiency, and use it for determining the execution timing of the dressing process, calculating the polishing amount of the workpiece, etc. Is described.

[0005]

However, in these prior arts 1 and 2, no consideration has been given to the point that the polishing rate in the wafer surface can be made uniform and the variation in the in-plane average polishing rate can be coped with. . Prior Art 3 also considers the point of calculating the polishing efficiency of the polishing pad, but does not sufficiently consider the point of flattening in the wafer surface. Further, in the prior arts 1, 2, and 3, no consideration was given to preventing the occurrence of scratches such as scratches on the surface of the wafer.

[0006] An object of the present invention is to solve the above problems.
To provide a processing method, a device and a semiconductor substrate processing method for improving the flatness processing accuracy of a workpiece by making a polishing rate uniform in a processing surface in a polishing process such as CMP. It is in. Another object of the present invention is to provide a polishing process such as a CMP process in which a process is performed in accordance with a variation in an average polishing rate for each workpiece such as a semiconductor substrate to uniformly process a plurality of workpieces, and It is an object of the present invention to provide a processing method and apparatus for performing stable processing, and a method for processing a semiconductor substrate. Also,
Another object of the present invention is to provide a processing method, a device, and a method for processing a semiconductor substrate which are capable of performing processing without causing scratches on a processing surface of a workpiece such as a semiconductor substrate in polishing processing such as CMP. To provide.

[0007]

In order to achieve the above object, the present invention provides a flatness measuring step for measuring the flatness of a polishing pad placed on a surface plate, and a measuring method for the flatness measuring step. A dressing step of dressing the polishing pad by controlling the movement of the dresser in accordance with the flatness of the polishing pad, and polishing the work surface of the workpiece with respect to the polishing pad dressed in the dressing step. The loose abrasive grains supplied and sprayed on the surface of the pad are pressed and interposed, and a relatively rubbing motion is performed between the workpiece and the polishing pad to grind the workpiece surface of the workpiece flat. And a processing method such as CMP characterized by having a processing step. Further, the present invention provides a surface roughness measuring step of measuring the surface roughness of a polishing pad placed on a surface plate, and a dresser according to the surface roughness of the polishing pad measured in the surface roughness measuring step. A dressing step of dressing the polishing pad by controlling a dressing amount of the polishing pad, and a free polishing method in which a processing surface of a workpiece is supplied to the polishing pad dressed in the dressing step and supplied to the surface of the polishing pad. And pressing the workpiece with the grains interposed therebetween, and performing a motion of relatively rubbing between the workpiece and the polishing pad to polish the workpiece surface of the workpiece flat. This is a processing method such as CMP.

Further, the present invention provides a dressing step of dressing a polishing pad placed on a surface plate with a dresser, and a processing surface of a workpiece with respect to loose abrasive particles supplied and dispersed on the surface of the polishing pad. Free abrasive grains measuring step of measuring the distribution or amount in the, controlling the supply amount of free abrasive grains according to the distribution or amount of free abrasive grains in the surface to be processed measured in the free abrasive grain measuring step The free abrasive grain supply spraying step of supplying and spraying on the surface of the polishing pad, and the polishing surface dressed in the dressing step, the workpiece surface of the workpiece was supplied and sprayed in the free abrasive grain supply spraying step. Having a processing step of pressing the workpiece with loose abrasives interposed therebetween, and performing a relative rubbing motion between the workpiece and the polishing pad to flatly grind a workpiece surface of the workpiece. A processing method such as CMP characterized. The present invention also provides a surface roughness measuring step of measuring the surface roughness of a polishing pad placed on a surface plate, a dressing step of dressing the polishing pad with a dresser, and a polishing machine dressed in the dressing step. Movement of pressing a processing surface of a workpiece against a pad with loose abrasive particles supplied and sprayed on the surface of the polishing pad, and relatively rubbing between the workpiece and the polishing pad. A polishing step of controlling the amount of polishing according to the surface roughness of the polishing pad measured in the surface roughness measuring step and polishing the processed surface of the workpiece flat. This is a processing method such as CMP.

Further, the present invention provides a free abrasive grain measurement for measuring a distribution or an amount of free abrasive grains supplied and sprayed on a surface of a polishing pad placed on a surface plate on a work surface of a workpiece. Process, a dressing step of dressing the polishing pad with a dresser, and for the polishing pad dressed in the dressing step, the processing surface of the workpiece, the free abrasive grains supplied and sprayed on the surface of the polishing pad. Interposed and pressed, causing a relative rubbing motion between the workpiece and the polishing pad, according to the distribution or amount of free abrasive grains in the work surface measured in the free abrasive grain measuring step. A polishing step of controlling the amount of polishing to flatten the surface to be processed of the object to be processed, such as CMP. Further, the present invention measures the elastic modulus or the bubble rate of the polishing pad placed on the surface plate, and the polishing pad reaches the service limit based on the measured elastic modulus or the bubble rate of the polishing pad. A determining step of determining whether or not the polishing process has been performed; and supplying a processed surface of the workpiece to the polishing pad surface with respect to the polishing pad determined to be usable in the determining step and placed on the surface plate. The loose abrasive grains sprayed or the fixed abrasive grains embedded in the polishing pad are interposed and pressed, and the workpiece is subjected to a relative rubbing motion between the workpiece and the polishing pad, thereby causing the workpiece surface of the workpiece to be rubbed. And a processing step of polishing or grinding the flat surface.

Further, the present invention provides a dressing step of dressing a polishing pad placed on a surface plate with a dresser, measuring an elastic modulus or a bubble rate of the polishing pad, and measuring the measured elastic modulus of the polishing pad. Or a determination step of determining whether the polishing pad has reached the use limit based on the bubble rate, and for the polishing pad placed on the surface plate is determined to be usable in the determination step, The work surface of the work is pressed against the surface of the polishing pad with loose abrasive particles supplied and dispersed therebetween, and the work is performed by relatively rubbing between the work and the polishing pad. And a processing step of polishing the surface to be processed of the object flatly.

Further, the present invention is a method for processing a semiconductor substrate, comprising processing an insulating film formed on a semiconductor substrate by using the above processing method. Also, the present invention
A surface plate on which a polishing pad is placed, a flatness measuring means for measuring the flatness of the polishing pad, and a polishing pad which controls movement in accordance with the flatness of the polishing pad measured by the flatness measuring means. A dressing means (dresser device) for dressing, and a polishing pad dressed by the dressing means, pressing a work surface of a workpiece with intervening loose abrasive particles supplied and dispersed on the surface of the polishing pad;
A processing device for performing a relative rubbing motion between the workpiece and the polishing pad to polishes a workpiece surface of the workpiece flatly. is there. Further, the present invention is characterized in that the flatness measuring means in the processing apparatus such as the CMP is configured to optically measure the displacement of the surface of the polishing pad.

Further, the present invention provides a surface plate on which a polishing pad is placed, surface roughness measuring means for measuring the surface roughness of the polishing pad, and a surface of the polishing pad measured by the surface roughness measuring means. Dresser means for dressing the polishing pad by controlling the dressing amount in accordance with the roughness, and for the polishing pad dressed by the dresser means, the surface to be processed of the workpiece is supplied and dispersed on the surface of the polishing pad. Processing means for pressing the work piece with the loose abrasive particles interposed therebetween and making a relative rubbing motion between the work piece and the polishing pad to flatly grind the work surface of the work piece. And a processing apparatus such as CMP. Further, the present invention relates to the above C
The surface roughness measuring means in a processing apparatus such as an MP is configured to measure a regular reflectance and / or a diffuse reflectance of light from the surface of the polishing pad. Further, the present invention provides a surface plate on which a polishing pad is placed, a dresser means for dressing the polishing pad, and a free abrasive grain supplied and sprayed on the surface of the polishing pad in a processing surface of the workpiece. Free abrasive grain measuring means for measuring the distribution or amount, and a polishing pad by controlling the supply amount of free abrasive grains in accordance with the distribution or amount of free abrasive grains in the surface to be processed measured by the free abrasive grain measuring means The free abrasive supplied and sprayed by the free abrasive grain supply / spraying means to the surface of the workpiece with respect to the free abrasive grain supply / spreading means for supplying and spraying the surface of the workpiece and the polishing pad dressed by the dresser means. Pressing means with grains interposed therebetween, and a processing means for performing a motion of relatively rubbing between the workpiece and the polishing pad to flatly grind a workpiece surface of the workpiece. CMP etc. It is a processing apparatus.

Further, according to the present invention, the free abrasive grain measuring means in the processing apparatus such as the CMP is configured to detect scattered light generated from the free abrasive grains through an observation window provided partially on the polishing pad. It is characterized by having done. Also,
The present invention provides a surface plate on which a polishing pad is placed, a surface roughness measuring means for measuring the surface roughness of the polishing pad, a dresser means for dressing the polishing pad, and a polishing pad dressed by the dresser means. On the other hand, the work surface of the work is pressed against the surface of the polishing pad with the loose abrasive particles supplied and dispersed therebetween, and the movement of relatively rubbing between the work and the polishing pad is performed. Processing means for controlling the amount of polishing in accordance with the surface roughness of the polishing pad measured in the surface roughness measuring step and polishing the processing surface of the workpiece flat. It is a processing device such as CMP. Further, the present invention provides a surface plate on which a polishing pad is placed, and a free abrasive particle measurement for measuring a distribution or an amount of free abrasive particles supplied and sprayed on the surface of the polishing pad on the surface to be processed of the workpiece. Means, dresser means for dressing the polishing pad, and, for the polishing pad dressed by the dresser means, the surface to be processed of the workpiece, interposed with free abrasive grains supplied and dispersed on the surface of the polishing pad. To make a relative rubbing motion between the workpiece and the polishing pad, and polishing according to the distribution or amount of free abrasive grains in the work surface measured in the free abrasive grain measuring step. Processing means for controlling the amount of the workpiece to polish the surface to be processed of the workpiece flat.
P and other processing devices.

Further, the present invention provides a surface plate on which a polishing pad is placed, measuring means for measuring the elastic modulus or bubble rate of the polishing pad, and an elastic modulus or bubble rate of the polishing pad measured by the measuring means. Determining means for determining whether or not the polishing pad has reached a use limit based on the polishing pad, and determining whether the polishing pad can be used by the determining means and placing the polishing pad on a surface plate, Surface of the polishing pad is pressed with intervening loose abrasive particles supplied or dispersed on the surface of the polishing pad or fixed abrasive particles embedded in the polishing pad, and relatively rubbed between the workpiece and the polishing pad. And a processing means for performing a moving motion so as to flatten or grind a processing surface of the processing object.

Also, the present invention provides a surface plate on which a polishing pad is placed, a dresser means for dressing the polishing pad, a measuring means for measuring the elasticity or bubble rate of the polishing pad, and a measuring means for measuring the elasticity or bubble rate of the polishing pad. Determining means for determining whether or not the polishing pad has reached a use limit based on the elastic modulus or bubble rate of the polishing pad, and the determining means determines that the polishing pad can be used and is placed on a surface plate. The processing surface of the workpiece is pressed against the polishing pad with the loose abrasive particles supplied and sprayed on the surface of the polishing pad, and the workpiece is relatively rubbed between the workpiece and the polishing pad. And a processing means for making the surface to be processed of the object to be polished flat by moving the workpiece.
Further, the present invention, the measurement means in the above processing apparatus, when the elastic modulus of the polishing pad is constituted by an air micro sensor,
The polishing pad is characterized in that a dielectric constant is measured in the case of a bubble rate.

As described above, according to the above configuration,
In a polishing process such as CMP, it is possible to realize each of a uniform polishing rate in a surface to be processed, a stabilization of an average in-plane polishing rate, and a reduction in scratches. Factors that vary the polishing rate include the flatness of the polishing pad, the surface roughness of the processed surface of the polishing pad, and the distribution of free abrasive grains. In addition, factors that cause scratches include the elastic modulus and bubble rate of the polishing pad. According to the configuration of the present invention, a dresser in which diamond abrasive grains are embedded is called a dresser in which diamond abrasive grains are embedded so as to appropriately correspond to the state that changes momentarily with the polishing use time.
And the like can be controlled. Further, by measuring the elastic modulus or the bubble rate of the polishing pad, it is possible to extract a time immediately before the polishing pad reaches its usage limit, and it is possible to prevent the occurrence of scratches.

[0017]

BEST MODE FOR CARRYING OUT THE INVENTION A CMP (Chemical Mechanical Polishing) for scattering free abrasive grains such as silica on a polishing pad according to the present invention to flatten and polish a surface of a workpiece such as a wafer.
A description will be given of an embodiment of a polishing or grinding method and apparatus for embedding fixed abrasive grains such as a diamond on a polishing pad and similarly grinding a surface of a workpiece such as a wafer with reference to the drawings. I do. In recent years, in a semiconductor wafer on which semiconductor chips are arranged, it is necessary to form a multi-layered wiring layer.
It has become necessary to planarize the surface of an interlayer insulating film such as O ₂ or SiN by CMP and form a wiring layer thereon.
Therefore, in this embodiment, a case will be described in which a thin film such as an interlayer insulating film formed on the surface of a workpiece such as a wafer is polished by CMP and flattened. But,
This embodiment is similarly effective for grinding with fixed abrasive grains. Further, as a workpiece, a lens or the like whose final processed surface shape is not flat is also effective.

First, the configuration of an embodiment of a polishing or grinding method and an apparatus therefor according to the present invention will be described with reference to FIGS. FIG. 1 is a schematic diagram showing a configuration of an embodiment according to the present invention. FIG. 2 shows a configuration of a CMP apparatus according to an embodiment of the present invention. The embodiment according to the present invention polishes a rotating platen 4 configured to fix and revolve a polishing pad 3 formed of foamed polyurethane or the like, and a chuck 1 that grips a workpiece 2 such as a wafer. A vertical movement mechanism 11 for pressing against the pad 3,
To press down a horizontal moving mechanism 12 for reciprocating the chuck 1 in the radial direction of the polishing pad 3 and a polishing mechanism 10 including a rotating mechanism for rotating the chuck 1 and a dresser 6 for dressing the polishing surface of the polishing pad 3. A vertical moving mechanism 21, a horizontal moving mechanism 22 for reciprocating the dresser 6 in the radial direction of the polishing pad 3, and a dresser mechanism 20 including a rotating mechanism for rotating the dresser 6 in rotation, and free abrasive grains such as silica in a solvent. And a slurry supply mechanism 30 having a slurry supply nozzle for spraying the slurry on the polishing pad 3 in a mixed state. By the way, for example, foamed polyurethane is used as the polishing pad 3 of CMP. In addition, the CMP of the above embodiment
The apparatus has been described as a rotary type for rotating the surface plate and the polishing pad. However, a linear moving system for linearly moving the polishing pad on the surface plate may be used.

Therefore, the surface of the workpiece 2 such as a wafer is
Based on the interposition of the slurry supplied onto the polishing pad 3 by the slurry supply mechanism 30, the polishing pressure given by the vertical movement mechanism 11, and the rotation of the chuck 1 and the radial movement of the polishing pad 3 by the horizontal movement mechanism 12 By the swinging motion (reciprocating motion) and the revolving motion of the rotating disk 4, polishing is performed flat. That is, in the polishing mechanism 10,
The surface of the workpiece 2 is polished flat so as to always follow the surface condition of the polishing pad 3 dressed by the dresser 6. On the other hand, in the dresser mechanism 20,
At the same time as polishing, the surface of the polishing pad 3 is called a dresser 6 in which diamond abrasive grains are embedded in order to always ensure a certain surface roughness, and so-called dressing is performed. Also in the dresser mechanism 20, dressing pressure is applied by the vertical movement mechanism 20, and the rotation of the dresser 9 by the rotation mechanism and the reciprocation of the dresser 9 in the radial direction of the polishing pad 3 by the horizontal movement mechanism 22 cause the radius of the polishing pad 3. While performing dressing in the directions, the revolving rotation of the rotating platen 4 performs dressing for the entire polishing pad 3. In any case, the dresser mechanism 20 can control the swing range of the dresser 6 by the horizontal movement mechanism 22, the rotation speed by the rotation mechanism, and the vertical movement mechanism 2.
2 is the only pressing force on the polishing pad.

However, even if the surface of the polishing pad 3 is always dressed with the dresser 6, the flatness of the polishing pad, the surface roughness of the polishing pad processing surface,
In addition, the distribution of the free abrasive grains fluctuates, and the polishing rate (the amount of polishing per unit time) on the surface of the workpiece 2 by the polishing mechanism 10 varies. That is, after the dressing, when the flatness of the polishing pad fluctuates and the flatness of the surface of the polishing pad 3 deteriorates, the polishing rate (amount of polishing per unit time) becomes non-uniform in the processed surface of the workpiece. . This is because if the polishing pressure by the free abrasive grains is concave due to the unevenness of the surface shape of the polishing pad 3, the polishing pressure is small, and if the polishing pressure is convex, it is large. When the workpiece 2 is polished by the polishing mechanism 10, a stable polishing rate must be ensured unless a certain required amount of abrasive grains exists between the workpiece 2 and the polishing pad 3. Can not. Thus, the workpiece 2
Only the free abrasive grains interposed between the processing surface of the polishing pad 3 and the polishing pad 3 contribute to the processing, but the free abrasive grains scattered on the polishing pad due to the surface roughness of the surface of the polishing pad 3, The ratio between the surface to be processed and the polishing pad changes, and the polishing amount also changes. However, by controlling the flow rate at which the slurry is supplied to the polishing pad surface in the slurry supply mechanism 30, the amount of free abrasive grains that actually contributes to polishing can be controlled.

When foamed polyurethane or the like is used as the polishing pad 3, the slurry solvent may be contained in the foamed polyurethane foam during polishing.
The polishing pad 3 has a higher elastic modulus as the polishing use time becomes longer. In addition, as the polishing use time becomes longer, the bubbles of the foamed polyurethane are filled up with the slurry solvent and the coagulated abrasive grains. in this way,
When the elastic modulus of the polishing pad 3 is increased, the rigidity of the support of the free abrasive grains by the polishing pad becomes too large, and as a result, the cutting depth by the free abrasive grains becomes too deep, and scratches and the like are generated on the surface of the workpiece 2. Become. Whatever it is,
As the operating time of the polishing pad becomes longer, the polishing pad 3
When the elastic modulus and bubble rate of the workpiece 2 fluctuate and reach the use limit, a scratch or the like is generated on the surface of the workpiece 2.

Therefore, in the embodiment according to the present invention, as shown in FIG. 1, a pad flatness measuring means 40 for measuring the flatness of the polishing pad 3 dressed by the dresser mechanism 20, and a dressing mechanism by the dresser mechanism 20. Pad surface roughness measuring means 50 for measuring the surface roughness of the polished polishing pad 3
A pad elastic modulus measuring unit 70 for measuring the elastic modulus of the polishing pad 3; a pad bubble ratio measuring unit 80 for measuring the bubble ratio of the polishing pad 3; and the observation window 5 provided on the polishing pad and the rotating disk 4, for example. And a distribution measuring means 60 for measuring the distribution of the slurry in the surface of the workpiece. Furthermore, in the embodiment according to the present invention,
Dresser control data for controlling the dresser 15, slurry control data for controlling the supply of slurry, and chuck control data for controlling the chuck 1 based on the measurement data measured by these measuring means 40, 50, 70, 80, and 60. A calculation means (CPU) 90 is provided for creating the image data. The dresser mechanism 20 is controlled by the dresser control device 201 based on the dresser control data created by the calculation means 90, and based on the slurry control data created by the calculation means 90. The slurry control device 301 controls the slurry supply mechanism 30 and the chuck control device 101 controls the polishing mechanism 10 based on the chuck control data created by the calculation means 90. The processing means (apparatus) is constituted by the polishing mechanism 10 and the chuck control apparatus 101, the dresser means (apparatus) is constituted by the dresser mechanism 20 and the dresser control apparatus 201, and the loose abrasive supply and dispersion means is a slurry supply mechanism. 30 and a slurry control device 301.

Next, an embodiment of the pad flatness measuring means 101 for measuring the flatness of the polishing pad 3 will be described with reference to FIGS.
This will be described in detail with reference to FIG. FIG. 3 is a diagram of the CMP apparatus viewed from the side. As the pad flatness measuring means 40, in particular, since the flatness in the radial direction of the polishing pad greatly affects the polishing rate on the workpiece, the radius of the polishing pad 3 is measured so that the flatness in the radial direction of the polishing pad 3 can be measured. For example, about seven laser displacement sensors 41 composed of a laser interferometer or the like are arranged in the direction. The pad flatness measuring means 4
As 0, for example, it is possible to run (scan) on a member that supports one displacement sensor 41 in the polishing pad radial direction. The number of the displacement sensors 41 may be appropriately set according to the diameter of the polishing pad and the required flatness resolution.

FIG. 4 is an example in which the result measured by the laser displacement sensor 41 is taken into the calculation means 90 and is graphed. That is, according to the laser displacement sensor 41, the flatness in the radial direction of the polishing pad 3 dressed by the dresser mechanism 20 can be measured, and as a result, the flatness is degraded around the center of the radial distance. Can be grasped. FIG. 5 shows the pad flatness measuring means 4.
0 shows another embodiment. This is achieved by irradiating a slit light from a laser light source 42 onto the surface of the polishing pad 3 in an oblique direction, capturing a displacement of the slit light corresponding to the flatness of the polishing pad 3 by a CCD camera 43, and measuring the displacement. It was configured to measure flatness. FIG. 6 shows the result of taking the slit light measurement result by the CCD camera 43 into the calculating means 90 and converting it into the polishing pad flatness. Thus, FIG.
Unlike the embodiment shown in FIG. 1, continuous flatness data can be obtained.

Next, the calculation means 90 creates control data based on the flatness data of the polishing pad measured by the pad flatness measurement means 40, and based on the created control data, the dresser control device 201 causes the dresser mechanism 20 to operate. Will be described with reference to FIGS. 1, 4, and 7 to 9. FIG. 7 shows a laser displacement sensor 4 which is an embodiment of the pad flatness measuring method 40 described with reference to FIG.
FIG. 4 is a diagram showing a case where No. 1 is used. The dresser 6 moves while rotating on the polishing pad 3 in the radial direction by the horizontal moving mechanism 22. The pressing force against the polishing pad 3 is controlled using the vertical movement mechanism 21 while measuring the force by, for example, a load cell. For example, in the case where the pad flatness shown in FIG. 4 is measured, the calculation means 90 calculates the data for reducing the moving speed of the horizontal moving mechanism 22 near the center and the outer periphery of the convex polishing pad as shown in FIG. The movement speed of the horizontal movement mechanism 22 is reduced by giving the created data to the dresser control device 201 as shown in FIG.
By increasing the amount of sharpening near the center and the outer periphery of the polishing pad by controlling as shown in FIG.
Can be improved, and as a result, the processing accuracy of the flatness for polishing the workpiece can be significantly improved, for example, from ± 0.05 μm. The calculation means 90
9, data for increasing the rotation speed of the dresser near the center and the outer periphery of the polishing pad is created, and the created data is given to the dresser control device 201 so that the rotation speed of the dresser 6 is plotted. By controlling as shown in FIG. 9, the sharpening amount near the center and the periphery of the polishing pad can be increased, and the flatness of the polishing pad 3 can be improved. In addition, the same effect can be obtained by controlling the vertical movement mechanism 21 by the dresser control device 201 to similarly increase the pressing force in the vicinity of the center and the outer periphery of the polishing pad. Each of these techniques is also effective independently,
It is also effective to use them in combination.

Next, an embodiment of the pad surface roughness measuring means 50 for measuring the surface roughness of the polishing pad 3 will be described with reference to FIGS.
This will be described in detail with reference to FIG. The pad surface roughness measuring means 50 shown in FIG. 10 irradiates the polishing pad 3 with light emitted from a light source 51 such as a laser, and specularly reflects light (0th-order diffracted light) from the polishing pad 3 through a condenser lens 57. The light is condensed, reflected by a half mirror 52, detected by a photodetector 53 such as a photomultiplier, and diffused light (first-order or higher-order diffracted light) from the polishing pad 3.
Is condensed by the elliptical mirror 55, reflected by the half mirror 56, and detected by the light receiver 54. For example, the intensity of the regular reflection light detected by the light receiver 53 and the intensity of the scattered light detected by the light receiver 54 are calculated. In this configuration, the surface roughness of the polishing pad is measured in a ratio.
It is necessary to optimize the luminous flux of the light applied to the polishing pad 3 according to the standard surface roughness of the polishing pad. For example,
As the surface roughness of the polishing pad 3 increases, the regular reflectance decreases, the diffuse reflectance increases, and conversely, the polishing pad 3
Since the regular reflectance increases and the diffuse reflectance decreases when the surface roughness of the photodetector 5 decreases.
The surface roughness of the polishing pad can be measured by, for example, calculating the ratio between the intensity of the specularly reflected light detected in step 3 and the intensity of the scattered light detected in the light receiver 54 by the calculation means 90. As described above, the relationship between the surface roughness of the polishing pad 3 and the reflectance is obtained in advance and input to the calculating means 90, so that the calculating means 90 can measure the surface roughness with higher accuracy. The advantage of using both in combination is effective when the light absorption rate of the polishing pad 3 varies. This is because the amount of light irradiated and the amount of reflected and absorbed light are expressed by the following equation (2), and it is impossible to analyze separately the fluctuation of the amount of absorbed light by specular reflection and diffusely reflected light alone. Because it becomes. In other words, when the polishing pad changes every moment depending on the use condition, it is not possible to accurately measure the fluctuation of the reflectance by only measuring one of the regular reflection and the diffuse reflection. Therefore, both the regular reflection light amount and the diffuse reflection light amount were measured, and the ratio was determined. By determining the relationship between the ratio of the amount of diffuse reflection light / the amount of regular reflection light and the surface roughness in advance, it is possible to extract only the difference in reflectance caused by the surface roughness.

Irradiation light quantity = specular reflection light quantity + diffuse reflection light quantity + absorption light quantity (Equation 2) In any case, the regular reflectance and the diffuse reflectance change in accordance with the change in the surface roughness of the polishing pad 3. It is possible to measure the surface roughness of the polishing pad using only the diffused light detected by the detector 54 or only the specularly reflected light detected by the light receiver 53. Further, in the specular reflection detection optical system,
A plurality of light receivers 53 for detecting regular reflection light are installed at respective positions with different optical path lengths, and each light receiver 53 detects an image (image formed) that matches the unevenness of the polishing pad, By interpolating a plurality of focused images detected from the respective light receivers 53 and matching the unevenness of the polishing pad, an image signal corresponding to the surface roughness of the polishing pad can be detected. By the way, in order to remove the reflection noise due to the slurry existing on the polishing pad 3, it is also effective to blow the air to the polishing pad with the nozzle 57 to remove the slurry from the measurement range by the pad surface roughness measuring means 50. The present nozzle 57 is not essential, but when used, it is better to allow a sufficient distance from the chuck 1 so as not to cause a scratch.

As described above, the pad surface roughness measuring means 50 can optically measure the surface roughness of the polishing pad 3 as shown in FIG. The surface roughness of the polishing pad 3 increases as the polishing time increases.

Next, the calculating means 90 creates control data based on the polishing pad surface roughness data measured from the pad surface roughness measuring means 50, and the dresser control device 201 Mechanism 20
1 and / or a method for controlling the polishing apparatus 10 by the chuck controller 101.
2 will be described. That is, the calculating means 90 calculates the ratio between the intensity of the specular reflection light detected by, for example, the light receiver 53 and the intensity of the scattered light detected by the light receiver 54 of the pad surface roughness measuring means 50, as shown in FIG. As shown, the surface roughness of the polishing pad is measured, the dresser rotation speed data shown in FIG. 12 is calculated based on the measured surface roughness data, and the calculated dresser rotation speed data is transmitted to the dresser control device 201. I do. Dresser control device 201
By controlling the rotation speed of the dresser 6 based on the dresser rotation speed data, a desired surface roughness can be obtained, and as a result, the free abrasive grains scattered on the polishing pad can The ratio of entering the surface and the polishing pad is made substantially constant, and the polishing amount of the workpiece can be made substantially constant, so that the processing accuracy of the polishing can be improved.
That is, when the measured surface roughness of the polishing pad 3 becomes smaller, the rotation speed of the dresser is controlled to be faster to increase the sharpening amount. In addition, when the surface roughness is reduced, the pressing force of the dresser can be easily increased. It is also effective to control the dressing amount by combining these.

The calculating means 90 calculates the ratio of the intensity of the specular reflection light detected by the light receiver 53 and the intensity of the scattered light detected by the light receiver 54 of the pad surface roughness measuring means 50, for example. As shown in FIG. 11, the surface roughness of the polishing pad is measured, data relating to the polishing time in the polishing mechanism 10 is created based on the measured surface roughness data, and transmitted to the chuck control device 101. Chuck control device 10
1 is a polishing mechanism 1 based on the data on the polishing time.
By controlling the polishing time by 0, it is possible to obtain the same and stable polishing amount for the workpiece with respect to a slight variation in the surface roughness of the polishing pad. Further, by controlling the polishing pressure in accordance with the fluctuation of the measured surface roughness of the polishing pad, it is also possible to realize optimal polishing. In addition, by controlling the supply amount of the slurry in accordance with the variation in the surface roughness of the polishing pad to be measured, the ratio of free abrasive grains entering between the processing surface of the workpiece and the polishing pad is substantially constant. The polishing amount of the object can be made substantially constant.

Next, an embodiment of the distribution measuring means 60 for measuring the distribution of the slurry in the surface of the workpiece will be described in detail with reference to FIG. The distribution measuring means 60 in the surface of the slurry workpiece is provided with an optical system for measuring scattered light on the side opposite to the polished surface. An observation window 5 is partially provided in the polishing pad 3, and a light source 6 such as a laser is
1. A scattered light measurement optical system including a spatial filter 64, a lens 63, a polarization beam splitter 62, a detector 65, and a λ / 4 plate 66 is provided. S emitted from a light source 61 such as a laser
The polarized beam is reflected by the beam splitter 62, and λ
The light is converted into a circularly polarized beam by the / 4 plate 66, and is irradiated through the observation window 5 onto the surface of the workpiece 2 such as a wafer. The irradiated circularly polarized beam is scattered by free abrasive grains existing between the processing surface of the workpiece 2 and the polishing pad 3,
Only the scattered light is selected by the spatial filter 64 and received by the detector 65. The light returning as circularly polarized light is λ
The scattered light from the free abrasive grains, which is converted into P-polarized light by the / 4 plate 66 and condensed by the lens 63 through the polarization beam splitter 62 and is not shielded by the spatial filter 64, is detected by the detector 65. The spatial filter 64 shields scattered light generated from the circuit pattern on the inner surface of the workpiece 2 and is located at a position conjugate with the inner surface of the workpiece 2. In addition, a spatial filter (not shown) for blocking specularly reflected light from the observation window 5 is provided. Then, by measuring the intensity of the scattered light received by the detector 65 or its in-plane distribution, the amount of free abrasive grains existing between the work surface of the work 2 and the polishing pad 3 and contributing to polishing is measured. It is possible to measure the distribution of the slurry in the surface of the workpiece and the amount of the slurry represented by the following.

Next, the calculation means 90 creates control data based on the distribution data (average distribution or amount data) of the slurry in the workpiece surface measured by the slurry in-plane distribution measuring means 60, Based on the created control data, the slurry control device 301
And / or a method in which the chuck control device 101 controls the polishing apparatus 10 will be described with reference to FIGS. That is, the calculation means 90 calculates the slurry supply data based on the distribution data of the slurry in the work surface measured by the work in-plane distribution measurement means 60, and uses the calculated slurry supply data as a slurry control device. 30
Send to 1. The slurry control device 301 controls the slurry supply mechanism 30 based on the slurry supply data to spray the slurry on the polishing pad 3 with an optimum slurry supply amount. In other words, if the measured free abrasive grains tend to be insufficient, the amount of slurry supplied by the slurry supply mechanism 30 may be increased, and if the amount becomes excessive, control may be performed so as to decrease the amount of slurry supplied by the slurry supply mechanism 30.
In the case of excessive amount, it is only necessary to reduce the slurry supply amount because the rotating platen 4 revolves, and the slurry is constantly discharged by centrifugal force. Further, the polishing time by the polishing mechanism 10 may be controlled based on the measured distribution data of the slurry in the surface of the workpiece. This is because there is a correlation between the measured distribution data of the slurry in the surface of the workpiece and the polishing rate.

Next, an embodiment of the pad elastic modulus measuring means 70 for measuring the elastic modulus of the polishing pad 3 will be described in detail with reference to FIG. This pad elastic modulus measuring means 70
For example, the air micro sensors 71 and 72 are
And is arranged on the polishing surface of. The air microsensors 71 and 72 measure a pressure fluctuation ΔPd that fluctuates in accordance with a gap d that is a gap between the polishing pad 3 and compressed air, ie, a gap d when the compressed air having a pressure P is blown onto the polishing pad 3. is there. For example, the supply compressed air pressures P1 and P2 of the two air microsensors 71 and 72 (where P2>
P1. ), The gap amounts d1, d generated by the supply compressed air pressures P1, P2, respectively.
2 are measured as the pressure fluctuations ΔPd1 and ΔPd2 corresponding to. The supply air pressures P1 and P2 are measured from the two air microsensors 71 and 72, and at the same time, a reaction force is generated on the surface of the polishing pad 3 to reflect the compressed air P1 and P2. To generate gap amounts d1 and d2, respectively.
Pressure fluctuations ΔPd1 and ΔPd2 corresponding to d2, that is, gap amounts d1 and d2 are measured. Thus, the calculating means 90 obtains the elastic modulus of the polishing pad 3 based on P2, d2 and P1, d1 measured by the two air microsensors 71, 72 by the following equation (Equation 3). It becomes possible. Of course, the elasticity of the polishing pad does not need to be calculated by the calculating means 90, but can be calculated by the CPU or the like in the pad elasticity measuring means 70.

Elastic modulus = (P 2 −P 1) / (d 2 −d 1) (Equation 3) A case where the gap between the polishing pad 3 and the air microsensor in the state where compressed air is not blown can be accurately and always kept constant. Alternatively, when the gap is measured by means such as a displacement sensor, only one air microsensor may be used. This is because if the initial gap amount d0 before sending the compressed air is clear, the polishing is performed by the following equation (4) using the pressure measurement value P and the gap d by the air microsensor when the compressed air is blown. This is because the elastic modulus of the pad 3 can be calculated.

Elastic modulus = P / (d−d0) (Equation 4) Next, the calculating means 90 uses the elastic modulus of the polishing pad 3 measured by the pad elasticity measuring means 70 to determine the limit pad elastic modulus. Then, a method of outputting information such as an alarm to an operator or the like when the number has reached is described with reference to FIGS. 1 and 16. That is, as shown in FIG. 16, the calculating means 90 displays information such as an alarm when the pad elasticity reaches a certain use limit from the elasticity of the polishing pad 3 measured by the pad elasticity measuring means 70 as shown in FIG. And the like, such as display on output means 901. Then, the worker or the like replaces the polishing pad 3 of the usage limit with a new polishing pad based on the output of the information such as the alarm, so that the workpiece 2 is not scratched or the like.
Polishing can be continued. The calculating means 90 can also automatically replace the polishing pad by the replacement mechanism by issuing a command to a replacement mechanism (for example, a robot mechanism) for replacing the polishing pad with information such as an alarm. As shown in FIG. 16, the elastic modulus of the polishing pad 3 increases with the polishing use time due to factors such as the slurry solvent being included in the bubble portion of the polishing pad such as foamed polyurethane during polishing.

Next, an embodiment of the pad bubble rate measuring means 80 for measuring the bubble rate of the polishing pad 3 will be described in detail with reference to FIG. This pad bubble rate measuring means 80
The capacitance sensor 81 for measuring the dielectric constant of the polishing pad is provided above the polishing pad 3. In particular, the pad air bubble rate measuring means 80 may be provided not on the upper side but on the lower side. In the case of being provided on the lower side, it is necessary to embed in the rotating surface plate 4 because the rotating surface plate 4 exists.
When the polishing pad 3 is made of foamed polyurethane or the like,
The dielectric constant ε measured by the capacitance sensor 81 has the relationship of the following (Equation 5). ε0 is the dielectric constant of polyurethane, and ε1 is the known dielectric constant of air. α is the bubble rate of the polishing pad to be calculated. ε = (1−α) × ε0 + α × ε1 (Equation 5) Therefore, the calculating means 90 calculates the polishing pad 3 measured by the capacitance sensor 81 constituting the pad bubble rate measuring means 80.
The bubble rate α of the polishing pad 3 can be calculated from the following equation (Equation 6) from the dielectric constant ε. Since the permittivity ε0 of polyurethane and the permittivity ε1 of air are known values, they may be input in advance using the input means 902 or the like and stored in a storage device (not shown). Of course, the bubble rate of the polishing pad does not need to be calculated by the calculating means 90, but can be calculated by the CPU or the like in the pad bubble rate measuring means 80.

Α = (ε−ε0) / (ε1−ε0) (Equation 6) Next, the calculating means 90 determines the usage limit based on the bubble rate of the polishing pad 3 measured from the pad bubble rate measuring means 80. A method of outputting information such as an alarm to an operator or the like when the pad bubble rate is reached will be described with reference to FIGS. For example, the capacitance sensor 8 shown in FIG.
In the case where the bubble rate of the polishing pad calculated based on the dielectric constant ε measured in Step 1 deteriorates with time, the calculation means 90 displays alarm information for replacement of the polishing pad when the bubble rate falls below the usage limit value. The operator can be informed by outputting to the output means 901 such as. Therefore, by replacing the polishing pad with a new polishing pad by receiving the alarm information,
The workpiece 2 can be polished without generating scratches or the like. Note that it is obviously possible to automatically change the polishing pad using the measurement result.
As described above, the measurement of the elastic modulus of the polishing pad 3 by using the pad elastic modulus measuring means 70 and the measurement of the air bubble rate of the polishing pad 3 by using the pad porosity measuring means 80 In order to find a straight line that reaches the limit of use of the polishing pad in order to prevent scratches on the
Obviously, either method may be used. In any case, the generation of scratches can be prevented by releasing the slurry (free abrasive grains) that has aggregated in the bubble portion of the polishing pad 3 and has become huge. However, as the usage time of the polishing pad 3 becomes longer, the slurry solvent and the coagulated abrasive grains are filled up in the air bubbles, and scratches are generated. Therefore, by calculating the elastic modulus of the polishing pad 3 and the bubble rate of the polishing pad 3, the calculating means 90 extracts the immediately before the use limit of the polishing pad in which the slurry solvent and the coagulated abrasive grains are filled up in the bubble portion. You can do it.

In the embodiments described above, the embodiments of the non-contact measurement in each measurement technique have been described.
This is because when the measurement is performed in contact with the surface of the polishing pad, it is possible to prevent the surface of the polishing pad from being damaged and causing a scratch. However, if the contact pressure of the measurement probe is sufficiently small, a contact type measurement method may be used. Further, when a polishing pad in which fixed abrasive grains are embedded is used, the dresser 20 and the slurry supply mechanism 30 described in the above-described embodiment are generally unnecessary. Therefore, measurement of the elastic modulus and the bubble rate of the polishing pad is also effective when using a polishing pad in which fixed value abrasive grains are embedded.

[0039]

According to the present invention, in polishing such as CMP, the flatness of a polishing pad is measured, and dressing by a dresser is controlled in accordance with the measured flatness of the polishing pad. The polishing rate can be made uniform within the surface to be processed, and as a result, there is an effect that the accuracy of flatness processing of the workpiece can be improved. Further, according to the present invention, in a polishing process such as CMP, the surface roughness of the polishing pad and the distribution or amount of free abrasive grains in the surface to be processed of the workpiece are measured, and the measured surface of the polishing pad is measured. Dressing by a dresser, supply amount of free abrasive grains, polishing conditions, etc. are controlled according to the distribution or amount of roughness and free abrasive grains in the work surface, so that the average polishing for each workpiece such as semiconductor substrate Processing according to the change in the rate can be performed, and as a result, there is an effect that uniform and stable processing can be performed on a plurality of workpieces.

Further, according to the present invention, in the polishing process such as CMP, the elastic modulus and the bubble rate of the polishing pad are measured to determine whether the usage limit has been reached. Polishing can be performed without generating scratches on the work surface of the work, and the yield can be greatly improved. Further, according to the present invention, a highly accurate polishing process such as CMP can be performed on a semiconductor substrate.

[Brief description of the drawings]

FIG. 1 is a configuration diagram showing one embodiment of a CMP apparatus according to the present invention.

FIG. 2 is a perspective view showing one embodiment of a mechanical unit of the CMP apparatus according to the present invention.

FIG. 3 is a front view showing an embodiment of a pad flatness measuring means according to the present invention.

FIG. 4 is an explanatory diagram of measurement data measured by a pad flatness measuring unit shown in FIG. 3;

FIG. 5 is a perspective view showing another embodiment of the pad flatness measuring means according to the present invention.

FIG. 6 is an explanatory diagram of measurement data measured by a pad flatness measuring unit shown in FIG. 5;

FIG. 7 is a perspective view showing a mechanism of a CMP apparatus provided with a pad flatness measuring unit.

FIG. 8 is a diagram for explaining an embodiment in which the moving speed of the dresser is controlled according to the measured flatness of the polishing pad.

FIG. 9 is a view for explaining an embodiment in which the rotation speed of the dresser is controlled in accordance with the measured flatness of the polishing pad.

FIG. 10 is a schematic configuration diagram showing an embodiment of a pad surface roughness measuring means according to the present invention.

11 is an explanatory diagram of measurement data measured by the pad surface roughness measuring means shown in FIG.

FIG. 12 is a view for explaining an embodiment in which the rotation speed of the dresser is controlled in accordance with the measured surface roughness of the polishing pad.

FIG. 13 is a schematic configuration diagram showing an embodiment of a distribution measurement unit for a slurry-processed surface according to the present invention.

FIG. 14 shows a C having a distribution measuring means in the surface to be processed of slurry.
FIG. 2 is a perspective view showing a mechanism of the MP device.

FIG. 15 is a schematic configuration diagram showing one embodiment of a pad elastic modulus measuring means according to the present invention.

FIG. 16 is a view for explaining a method of using the measured elastic modulus data of the polishing pad.

FIG. 17 is a schematic configuration diagram showing one embodiment of a polishing pad bubble rate measuring means according to the present invention.

FIG. 18 is a diagram for explaining a method of using the measured bubble rate data of the polishing pad.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Chuck, 2 ... Workpiece (wafer), 3 ... Polishing pad, 4 ... Rotary surface plate, 5 ... Observation window, 6 ... Dresser, 1
0: polishing mechanism, 11: vertical moving mechanism, 12: horizontal moving mechanism, 20: dresser mechanism, 21: vertical moving mechanism, 22
... horizontal movement mechanism, 30 ... slurry supply mechanism, 40 ... pad flatness measuring means, 41 ... laser displacement sensor, 42 ... laser light source, 43 ... CCD camera, 50 ... pad surface roughness measuring means, 51 ... light source, 52 ... Half mirror, 53: light receiver, 54: light receiver, 55: elliptical mirror, 56: half mirror, 57: condenser lens, 58: nozzle, 60: distribution measuring means in the surface to be processed with slurry, 61: light source, 62 ... Polarizing beam splitter, 63 ... lens, 64 ... spatial filter,
65: Detector, 66: λ / 4 plate, 70: Pad elastic modulus measuring means, 71, 72: Air micro sensor, 80: Pad bubble rate measuring means, 81: Capacitance sensor, 90: Calculation means (CPU) , 101 ... chuck control device, 201 ...
Dresser control device 301 Slurry control device 90
1 ... output means, 902 ... input means.

 ──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Hidemi Sato 292 Yoshida-cho, Totsuka-ku, Yokohama-shi, Yokohama, Japan Inside the Manufacturing Research Laboratory, Hitachi, Ltd. (72) Inventor Ichiro Moriyama 6-16 Shinmachi, Ome-shi, Tokyo 3 F-term in Hitachi, Ltd. Device Development Center (reference) 3C058 AA07 AC04 BA02 BA07 BA09 BB02 BB06 BB08 BB09 CA01 CB01 CB03 DA02

Claims (15)

[Claims] A flatness measuring step of measuring a flatness of a polishing pad placed on a surface plate; and controlling a movement of a dresser in accordance with the flatness of the polishing pad measured in the flatness measuring step. A dressing step of dressing the polishing pad, and pressing the work surface of the work piece against the polishing pad dressed in the dressing step with loose abrasive particles supplied and dispersed on the surface of the polishing pad interposed therebetween. And a polishing step of causing the workpiece and the polishing pad to relatively rub against each other and polishing the workpiece surface of the workpiece flat. 2. A surface roughness measuring step of measuring the surface roughness of a polishing pad mounted on a surface plate, and a dresser according to the surface roughness of the polishing pad measured in the surface roughness measuring step. A dressing step of dressing the polishing pad by controlling the amount of dressing; and free abrasive grains supplied to the polishing pad dressed in the dressing step, by supplying the processing surface of the workpiece to the surface of the polishing pad. Pressurizing the workpiece, and performing a relative rubbing motion between the workpiece and the polishing pad to flatly grind a workpiece surface of the workpiece. Method. 3. A dressing step of dressing a polishing pad mounted on a surface plate with a dresser, and a distribution or a distribution of free abrasive grains supplied and sprayed on the surface of the polishing pad in a processing surface of the workpiece. Free abrasive grain measuring step of measuring the amount, controlling the supply amount of the free abrasive grains in accordance with the distribution or amount of the free abrasive grains in the surface to be processed measured in the free abrasive grain measuring step, and controlling the surface of the polishing pad The free abrasive grains supplied and sprayed in the free abrasive grain supply / spreading step are applied to the polishing surface dressed in the dressing step. A step of intervening and pressing to make a relative rubbing motion between the workpiece and the polishing pad so as to flatten the workpiece surface of the workpiece. Method. 4. A surface roughness measuring step of measuring a surface roughness of a polishing pad placed on a surface plate, a dressing step of dressing the polishing pad with a dresser, and a polishing pad dressed in the dressing step. On the other hand, the work surface of the work is pressed against the surface of the polishing pad with the loose abrasive particles supplied and dispersed therebetween, and the movement of relatively rubbing between the work and the polishing pad is performed. A polishing step of controlling the amount of polishing in accordance with the surface roughness of the polishing pad measured in the surface roughness measuring step and polishing the processed surface of the workpiece flat. Method. 5. A free abrasive grain measuring step for measuring a distribution or an amount of free abrasive grains supplied and sprayed on a surface of a polishing pad placed on a surface plate on a surface to be processed of the workpiece, A dressing step of dressing the polishing pad with a dresser, and pressing the work surface of the work piece against the polishing pad dressed in the dressing step with the intermediary of loose abrasive particles supplied and dispersed on the surface of the polishing pad. The movement of rubbing relatively between the workpiece and the polishing pad, the amount of polishing in accordance with the distribution or amount of free abrasive grains in the work surface measured in the free abrasive grain measurement step, A processing step of controlling the surface of the workpiece to be polished flat. 6. An elastic modulus or a bubble rate of a polishing pad placed on a surface plate is measured, and the polishing pad reaches a service limit based on the measured elastic modulus or a bubble rate of the polishing pad. A determining step of determining whether or not the workpiece is to be used in the determining step; and supplying the processing surface of the workpiece to the polishing pad placed on the surface plate on the surface of the polishing pad. The fixed abrasive grains embedded in the free abrasive grains or the polishing pad are pressed and interposed, and a relative rubbing motion is performed between the workpiece and the polishing pad to cause the workpiece surface of the workpiece to be rubbed. A processing step of polishing or grinding flat. 7. A dressing step of dressing a polishing pad placed on a surface plate with a dresser, measuring an elastic modulus or a bubble rate of the polishing pad, and measuring the elastic modulus or the bubble rate of the polishing pad. A determining step of determining whether or not the polishing pad has reached a use limit based on the polishing pad; and The work surface is pressed with intervening loose abrasive particles supplied and sprayed on the surface of the polishing pad, and the movement of relatively rubbing between the work object and the polishing pad is performed. A processing step of polishing the surface flat. 8. A method for processing a semiconductor substrate, comprising processing an insulating film formed on a semiconductor substrate by using the processing method according to claim 1. 9. A surface plate on which a polishing pad is placed, flatness measuring means for measuring the flatness of the polishing pad, and movement control in accordance with the flatness of the polishing pad measured by the flatness measuring means. Dressing means for dressing the polishing pad, and pressing the work surface of the work piece against the polishing pad dressed by the dresser means with loose abrasive particles supplied and dispersed on the surface of the polishing pad interposed therebetween. A processing means for relatively moving the workpiece and the polishing pad so as to rub against each other, and polishing the workpiece surface of the workpiece flat. 10. A surface plate on which a polishing pad is placed, surface roughness measuring means for measuring the surface roughness of the polishing pad, and a surface roughness of the polishing pad measured by the surface roughness measuring means. Means for dressing the polishing pad by controlling the amount of dressing, and free abrasive grains supplied to the polishing pad dressed by the dresser means, by supplying the processing surface of the workpiece to the surface of the polishing pad. And a processing means for performing a relative rubbing motion between the workpiece and the polishing pad to flatly grind a workpiece surface of the workpiece. Processing equipment. 11. A surface plate on which a polishing pad is mounted, a dresser means for dressing the polishing pad, and a distribution of free abrasive grains supplied and sprayed on the surface of the polishing pad in the surface to be processed of the workpiece. Or a free abrasive grain measuring means for measuring the amount, and controlling the supply amount of the free abrasive grains in accordance with the distribution or the amount of the free abrasive grains in the surface to be processed measured by the free abrasive grain measuring means to control the polishing pad. A free abrasive grain supply / spreading means for supplying / spraying the surface, and a free abrasive grain supplied / sprayed by the free abrasive grain supply / spray means with respect to the polishing surface dressed by the dresser means. And press
A processing apparatus, comprising: processing means for performing a relative rubbing motion between the workpiece and the polishing pad so as to flatten a workpiece surface of the workpiece. 12. A surface plate on which a polishing pad is placed, a surface roughness measuring means for measuring the surface roughness of the polishing pad, a dresser means for dressing the polishing pad, and a polishing machine dressed by the dresser means. Movement of pressing a processing surface of a workpiece against a pad with loose abrasive particles supplied and sprayed on the surface of the polishing pad, and relatively rubbing between the workpiece and the polishing pad. Processing means for controlling the amount of polishing in accordance with the surface roughness of the polishing pad measured in the surface roughness measuring step, and polishing the work surface of the work piece flat. Processing equipment. 13. A surface plate on which a polishing pad is placed, and a free abrasive particle measuring means for measuring a distribution or an amount of free abrasive particles supplied and sprayed on the surface of the polishing pad in the surface to be processed. Dresser means for dressing the polishing pad; and, with respect to the polishing pad dressed by the dresser means, a processing surface of a workpiece is interposed with loose abrasive grains supplied and dispersed on the surface of the polishing pad. Pressing, making the movement relatively rubbing between the workpiece and the polishing pad, the amount of polishing according to the distribution or amount of free abrasive grains in the work surface measured in the free abrasive grain measuring step And a processing means for controlling the surface of the workpiece to be polished flat. 14. A platen on which a polishing pad is placed, measuring means for measuring an elastic modulus or a bubble rate of the polishing pad, and a measuring means for measuring an elastic modulus or a bubble rate of the polishing pad measured by the measuring means. Determining means for determining whether or not the polishing pad has reached a use limit; and a processing surface of a workpiece with respect to the polishing pad which is determined to be usable by the determining means and placed on a surface plate. Is pressed with the interposition of loose abrasive particles supplied or sprayed on the surface of the polishing pad or fixed abrasive particles embedded in the polishing pad, thereby causing a relative rubbing motion between the workpiece and the polishing pad. Processing means for polishing or grinding the surface of the workpiece to be processed flat. 15. A surface plate on which a polishing pad is mounted, a dresser means for dressing the polishing pad, a measuring means for measuring an elastic modulus or a bubble rate of the polishing pad, and a polishing pad measured by the measuring means. Determining means for determining whether or not the polishing pad has reached a use limit based on the elastic modulus or bubble rate of the polishing pad, and determining whether the polishing pad can be used by the determining means and placing the polishing pad on a surface plate. On the other hand, the work surface of the work is pressed against the surface of the polishing pad with the loose abrasive particles supplied and interposed therebetween, and a movement of relatively rubbing between the work and the polishing pad is performed. Processing means for polishing the surface of the workpiece to be processed flat.