Polishing pad and method for manufacturing polished product

Abstract

To provide a polishing pad that is low in slurry dependence of a selection ratio and can be used for high-precision torque endpoint detection, and a method for manufacturing a polished product using the same.SOLUTION: A polishing pad comprises a polishing layer that contains a water-soluble organic compound having a carboxylic acid group and / or a sulfonic acid group.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a method for manufacturing a polishing pad and a polished workpiece. [Background technology]

[0002] In the semiconductor manufacturing process, chemical mechanical polishing (CMP) is used for planarization after insulating film deposition and for forming metal wiring. One of the important technologies required for chemical mechanical polishing is the polishing end point detection to detect whether the polishing process is complete. For example, over-polishing or under-polishing with respect to the target polishing end point directly leads to product defects. Therefore, in chemical mechanical polishing, it is necessary to strictly control the amount of polishing by detecting the polishing end point.

[0003] Chemical mechanical polishing is a complex process, and the polishing speed (polishing rate) changes depending on the operating conditions of the polishing equipment, the quality of consumables (slurry, polishing pads, dressers, etc.), and the influence of variations in conditions over time during the polishing process. Furthermore, in recent years, the accuracy of the remaining film thickness and the uniformity of the surface are becoming increasingly strict in the semiconductor manufacturing process. For these reasons, it is becoming more difficult to detect the polishing end point with sufficient accuracy.

[0004] Known main methods for detecting the polishing end point include an optical end point detection method, a torque end point detection method, and an eddy current end point detection method.

[0005] In the optical end point detection method, the wafer is irradiated with light through a transparent window member on the polishing pad, and the end point is detected by monitoring the reflected light. However, slurry may leak from around the window member during polishing, which may reduce the detection accuracy. In addition, it is necessary to provide a window member with different materials and physical properties on the polishing pad, which causes problems such as uneven polishing in the area where the window member is provided.

[0006] In addition, in the torque end point detection method, the end point of polishing is indirectly detected from the torque of the rotating shaft caused by the difference in friction coefficient between materials (for example, see Patent Document 1). [Prior art documents] [Patent documents]

[0007] [Patent Document 1] Japanese Patent Application Publication No. 06-315850 Summary of the Invention [Problem to be solved by the invention]

[0008] Since the difference in the polishing speed between the film to be polished and the stopper film (hereinafter referred to as the "selectivity ratio") depends on the slurry used, the torque end point detection method has the problem that the end point cannot be detected accurately unless an appropriate slurry is selected. However, no technology has been proposed that solves this problem from the viewpoint of the polishing pad configuration.

[0009] The present invention has been made in consideration of the above problems, and aims to provide a polishing pad having a low slurry dependency of the selectivity ratio and capable of being used for highly accurate torque end point detection, and a method for manufacturing a polished workpiece using the same. [Means for solving the problem]

[0010] As a result of intensive research into solving the above problems, the inventors discovered that the above problems can be solved by using a polishing pad having a polishing surface in which the dynamic friction coefficients of an oxide film, such as a silicon oxide film, and a nitride film, such as a silicon nitride film, are different, and thus completed the present invention.

[0011] That is, the present invention is as follows. [1] The polishing layer contains a water-soluble organic compound having a carboxylic acid group and / or a sulfonic acid group. Polishing pad. [2] The content of the water-soluble organic compound is 0.01 to 10% by weight based on the total amount of the polishing layer. The polishing pad described in [1]. [3] The water-soluble organic compound is at least one selected from the group consisting of poly(meth)acrylic acid, malic acid, lactic acid, tartaric acid, gluconic acid, adipic acid, naphthalenesulfonic acid-formalin condensates, laurylbenzenesulfonic acid, and salts thereof. The polishing pad according to [1] or [2]. [4] The water-soluble organic compound is ammonium polyacrylate or a naphthalenesulfonic acid-formaldehyde condensate. The polishing pad according to any one of [1] to [3]. [5] The molecular weight of the water-soluble organic compound is 500 to 10,000. The polishing pad according to any one of [1] to [4]. [6] The method includes a polishing step of polishing a workpiece having an oxide film and a nitride film using the polishing pad according to any one of [1] to [5] to obtain a polished product, and an end point detection step of detecting an end point during the polishing by a torque method. A method for manufacturing polished workpieces. Effect of the Invention

[0012] According to the present invention, it is possible to provide a polishing pad having a low slurry dependency of the selectivity and capable of being used for highly accurate torque detection type end point detection, and a method for manufacturing a polished product using the same. [Brief description of the drawings]

[0013] [Figure 1] 1 is a schematic cross-sectional view of a polishing pad according to an embodiment of the present invention. [Diagram 2] FIG. 1 is a schematic diagram showing a film thickness control system installed in CMP. [Diagram 3] FIG. 1 is a schematic diagram showing the measurement principle of endpoint detection using a torque method. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0014] Below, we will explain in detail the embodiment of the present invention (hereinafter referred to as the "present embodiment"). However, the present invention is not limited to this embodiment, and various modifications are possible without departing from the gist of the present invention.

[0015] [Polishing pad] The polishing pad of this embodiment has a polishing layer containing a water-soluble organic compound having a carboxylic acid group and / or a sulfonic acid group (hereinafter also simply referred to as a "water-soluble organic compound").

[0016] As shown in FIG. 1, the polishing pad 10 of this embodiment includes a polishing layer 11 containing the water-soluble organic compound, and optionally includes a substrate layer 12. By including the water-soluble organic compound, the polishing layer 11 has a different friction coefficient with respect to the oxide layer and the nitride layer. Therefore, in the torque end point detection method, it is possible to detect the difference in torque of the rotating shaft caused by the difference in friction coefficient between materials with higher accuracy, and as a result, the accuracy of the end point detection is improved. The detailed configuration will be described below.

[0017] [Polishing layer] The polishing layer 11 has a polishing surface 11a for polishing an object to be polished. The polishing layer is not particularly limited as long as it contains a resin that is the main component constituting the polishing layer and a water-soluble organic compound different from the resin. Examples of the composition of the polishing layer include a foamed resin body, a non-foamed resin body, and a resin-impregnated substrate. In these compositions, the water-soluble organic compound can be mixed with the resin that is the main component.

[0018] Here, the foamed resin body refers to a foamed resin body that does not have a fiber substrate. The foam shape is not particularly limited, but examples thereof include spherical bubbles, nearly spherical bubbles, teardrop-shaped bubbles, and open bubbles in which each bubble is partially connected.

[0019] In addition, the non-foamed resin molded body refers to a non-foamed body composed of a specific resin without a fiber substrate. The non-foamed body refers to a body that does not have bubbles as described above. In this embodiment, the non-foamed resin molded body also includes a body in which a curable composition is attached to a substrate such as a film and cured. More specifically, the non-foamed resin molded body also includes a resin cured product formed by a labia coater method, a small diameter gravure coater method, a reverse roll coater method, a transfer roll coater method, a kiss coater method, a die coater method, a screen printing method, a spray coating method, or the like.

[0020] Furthermore, the resin-impregnated substrate refers to a substrate obtained by impregnating a fiber substrate with a resin. The fiber substrate is not particularly limited, but examples thereof include woven fabric, nonwoven fabric, and knitted fabric.

[0021] (Water-soluble organic compound) Water-soluble organic compounds are used to adjust the friction coefficient for oxide films such as silicon oxide films and nitride films such as silicon nitride films. By using a water-soluble organic compound, the friction adjustment function of the organic compound in the presence of a slurry is exerted, and in the torque end point detection method, it becomes possible to detect with high accuracy the difference in torque of a rotating shaft caused by the difference in friction coefficient between materials.

[0022] The water-soluble organic compound having a carboxylic acid group is not particularly limited, but examples thereof include poly(meth)acrylic acid, malic acid, lactic acid, tartaric acid, gluconic acid, adipic acid, and salts thereof.

[0023] The water-soluble organic compound having a sulfonic acid group is not particularly limited, but examples thereof include naphthalenesulfonic acid-formaldehyde condensates, laurylbenzenesulfonic acid, and salts thereof.

[0024] Among these, poly(meth)acrylic acid, naphthalenesulfonic acid-formaldehyde condensate and their salts are more preferred, and ammonium polyacrylate and naphthalenesulfonic acid-formaldehyde condensate are even more preferred. By using such water-soluble organic compounds, the detection accuracy in the torque end point detection method tends to be further improved. The water-soluble organic compounds may be used alone or in combination of two or more kinds.

[0025] The molecular weight of the water-soluble organic compound is preferably 90 to 15,000, more preferably 500 to 10,000, and even more preferably 500 to 2,000. When the molecular weight is within the above range, the detection accuracy in the torque end point detection method tends to be improved. When the water-soluble organic compound is a polymer, the "molecular weight of the water-soluble organic compound" refers to the number average molecular weight of the polymer.

[0026] The content of the water-soluble organic compound is preferably 0.01 to 10% by weight, more preferably 0.05 to 5% by weight, and even more preferably 0.1 to 3% by weight, based on the total weight of the polishing layer. When the content of the water-soluble organic compound is within the above range, the accuracy of end point detection in the torque end point detection method tends to be improved. Note that the "content of the water-soluble organic compound" refers to the total content when multiple water-soluble organic compounds are used.

[0027] (resin) The resin that is the main component constituting the polishing layer includes a wet-solidifiable resin, a dry-solidifiable resin, other curable resins, etc. These resins may be used alone or in combination of two or more kinds.

[0028] Here, "wet coagulation" refers to a method in which a resin solution in which a resin is dissolved is impregnated into a fiber substrate, and the fiber substrate is immersed in a bath of a coagulation liquid (such as water, which is a poor solvent for the resin), thereby coagulating and regenerating the resin in the impregnated resin solution. Alternatively, a resin solution in which a resin is dissolved may be applied to a film or the like, and the film may be immersed in a bath of the coagulation liquid to obtain a resin molded body that does not contain a fiber substrate. In this wet coagulation, the solvent in the resin solution is replaced with the coagulation liquid, so that the resin in the resin solution coagulates and coagulates. Note that bubbles are formed in areas other than the areas where the resin is coagulated and coagulated. The shape of the formed bubbles is not particularly limited, but they tend to be teardrop-shaped.

[0029] "Dry coagulation" refers to a method in which a liquid containing a prepolymer and a curing agent is impregnated into a fiber substrate, and the prepolymer and the curing agent are reacted to form a resin. Alternatively, a liquid containing a prepolymer and a curing agent may be applied to a film or the like, and the prepolymer and the curing agent may be reacted to obtain a molded resin body that does not include a fiber substrate. In this wet coagulation, a foam is obtained when gas is generated by the reaction between the prepolymer and the curing agent or when a foaming agent is used, and a non-foamed body is obtained in other cases. The shape of the foam is not particularly limited, but it tends to be spherical or approximately spherical.

[0030] Specific examples of each resin are given below, but the resin constituting the polishing layer of this embodiment is not limited to the following.

[0031] Examples of resins that can be wet-solidified include, but are not limited to, polyurethane-based resins such as polyurethane and polyurethane polyurea; acrylic-based resins such as polyacrylate and polyacrylonitrile; vinyl-based resins such as polyvinyl chloride, polyvinyl acetate and polyvinylidene fluoride; polysulfone-based resins such as polysulfone and polyethersulfone; acylated cellulose-based resins such as acetylated cellulose and butyrylated cellulose; polyamide-based resins; and polystyrene-based resins.

[0032] Among these, it is preferable to include a polyurethane resin. Examples of the polyurethane resin include, but are not limited to, polyester polyurethane resin, polyether polyurethane resin, and polycarbonate polyurethane resin. By using such a resin, the polishing rate tends to be further improved.

[0033] The prepolymer constituting the dry-solidifiable resin is not particularly limited, but examples thereof include an adduct of hexamethylene diisocyanate and hexanetriol; an adduct of 2,4-tolylene diisocyanate and polyoxytetramethylene glycol; an adduct of tolylene diisocyanate and hexanetriol; an adduct of tolylene diisocyanate and trimethylolpropane; an adduct of xylylene diisocyanate and trimethylolpropane; an adduct of hexamethylene diisocyanate and trimethylolpropane; and an adduct of isocyanuric acid and hexamethylene diisocyanate. The prepolymer may be used alone or in combination of two or more kinds.

[0034] The curing agent constituting the dry-solidifying resin is not particularly limited, but examples thereof include amine compounds such as 3,3'-dichloro-4,4'-diaminodiphenylmethane, 4-methyl-2,6-bis(methylthio)-1,3-benzenediamine, 2-methyl-4,6-bis(methylthio)-1,3-benzenediamine, 2,2-bis(3-amino-4-hydroxyphenyl)propane, 2,2-bis[3-(isopropylamino)-4-hydroxyphenyl]propane, 2,2-bis[3-(1-methylpropylamino)-4-hydroxyphenyl]propane, 2,2-bis[3-(1-methylpentylamino)-4-hydroxyphenyl]propane, 2,2-bis(3,5-diamino-4-hydroxyphenyl)propane, 2,6-diamino-4-methylphenol, trimethylethylenebis-4-aminobenzoate, and polytetramethylene oxide-di-p-aminobenzoate; ethylene glycol, propylene glycol, and the like. Examples of polyhydric alcohol compounds include polyhydric alcohol compounds such as ethylene glycol, diethylene glycol, trimethylene glycol, tetraethylene glycol, triethylene glycol, dipropylene glycol, 1,4-butanediol, 1,3-butanediol, 2,3-butanediol, 1,2-butanediol, 3-methyl-1,2-butanediol, 1,2-pentanediol, 1,4-pentanediol, 2,4-pentanediol, 2,3-dimethyltrimethylene glycol, tetramethylene glycol, 3-methyl-4,3-pentanediol, 3-methyl-4,5-pentanediol, 2,2,4-trimethyl-1,3-pentanediol, 1,6-hexanediol, 1,5-hexanediol, 1,4-hexanediol, 2,5-hexanediol, 1,4-cyclohexanedimethanol, neopentyl glycol, glycerin, trimethylolpropane, trimethylolethane, and trimethylolmethane. The curing agents may be used alone or in combination of two or more.

[0035] Other compositions constituting the curable resin are not particularly limited, and may be, for example, a photocurable composition containing a photopolymerization initiator and a polymerizable compound, a thermosetting composition containing a thermal polymerization initiator and a polymerizable compound, a thermosetting resin, a UV-curable resin, or a two-liquid mixed curable resin. The curable composition may also contain a crosslinking agent having two or more polymerizable functional groups, as necessary.

[0036] The polymerizable compound is not particularly limited, but examples thereof include (meth)acrylate, epoxy (meth)acrylate, urethane (meth)acrylate, and polyester (meth)acrylate.

[0037] The photopolymerization initiator is not particularly limited, but examples thereof include benzophenone-based compounds, acetophenone-based compounds, and thioxanthones. The thermal polymerization initiator is not particularly limited, but examples thereof include azo compounds such as 2,2'-azobisbutyronitrile, and peroxides such as benzoyl peroxide (BPO).

[0038] The thermosetting resin is not particularly limited, but examples thereof include phenol resin, epoxy resin, acrylic resin, urea resin, and formaldehyde resin.

[0039] The UV-curable resin is not particularly limited, but examples thereof include prepolymers having a number average molecular weight of about 1,000 to 10,000, acrylic (methacrylic) esters and their urethane modifications, thiokol-based compounds, etc., and reactive diluents and organic solvents can be used as appropriate depending on the application.

[0040] The two-liquid mixed curable resin is not particularly limited, but for example, prepolymers having different physical properties can be used.

[0041] [Base material layer] The polishing pad of this embodiment has a base layer on the opposite side of the polishing surface of the polishing layer. By having the base layer, the conformability to the workpiece to be polished is improved, and the uniformity of the polishing pressure on the workpiece tends to be improved.

[0042] The substrate layer is not particularly limited, and examples thereof include impregnated nonwoven fabrics and resin foams impregnated with resin. Examples of impregnated nonwoven fabrics include polyolefin-based, polyamide-based, polyester-based, and other nonwoven fabrics impregnated with polyurethane-based resins such as polyurethane and polyurethane polyurea, acrylic-based resins such as polyacrylate and polyacrylonitrile, vinyl-based resins such as polyvinyl chloride, polyvinyl acetate, and polyvinylidene fluoride, polysulfone-based resins such as polysulfone and polyethersulfone, acylated cellulose-based resins such as acetylated cellulose and butyrylated cellulose, polyamide-based resins, and polystyrene-based resins. Examples of resin foams include polyolefin-based foams, polyurethane-based foams, polystyrene-based foams, phenol-based foams, synthetic rubber-based foams, and silicone rubber-based foams.

[0043] [Method of manufacturing polishing pad] The polishing pad of this embodiment can be manufactured by known methods such as a method of bonding a polishing layer and a base layer together, or a method of forming a polishing layer on a base layer.

[0044] The method for forming the polishing layer is not particularly limited, and examples thereof include the above-mentioned wet solidification method, the above-mentioned dry solidification method, and a method for curing a curable resin, etc. In this embodiment, a method for making the polishing layer contain a compound having a carboxylic acid group and / or a sulfonic acid group includes a method of mixing a compound having a carboxylic acid group and / or a sulfonic acid group with a resin before curing and curing the resin in that state.

[0045] The method for forming the base layer is not particularly limited, and examples thereof include a method for forming each of the above foams by a known method.

[0046] [Method for manufacturing polished product] The method for producing a polished product of this embodiment includes a polishing step of polishing a workpiece using the above-mentioned polishing pad to obtain a polished product, and an end point detection step of detecting the end point during the polishing using a torque method.

[0047] [Polishing process] The polishing process may be a primary lapping process (rough lapping), a secondary lapping process (finish lapping), a primary polishing process (rough polishing), a secondary polishing process (finish polishing), or a process that combines these processes. Note that, here, "lapping" refers to polishing at a relatively high rate using coarse abrasive grains, and "polishing" refers to polishing at a relatively low rate using fine abrasive grains to improve the surface quality.

[0048] Among these, the polishing pad of the present embodiment is preferably used for chemical mechanical polishing. On the other hand, it can also be used for holding a workpiece in a machining process such as grinding or cutting. Hereinafter, the method for manufacturing the polishing product of the present embodiment will be described using chemical mechanical polishing as an example, but the method for manufacturing the polishing product of the present embodiment is not limited to the following.

[0049] The object to be polished is not particularly limited, but examples thereof include materials such as semiconductor devices and electronic components, in particular thin substrates (objects to be polished) such as Si substrates (silicon wafers), SiC (silicon carbide) substrates, GaAs (gallium arsenide) substrates, glass, and substrates for hard disks and LCDs (liquid crystal displays).

[0050] The polishing method may be a conventionally known method, and is not particularly limited. For example, first, the object to be polished held on a holding platen arranged to face the polishing pad is pressed against the polishing surface, and the polishing pad and / or the holding platen are rotated while supplying a slurry from the outside. The polishing pad and the holding platen may rotate in the same direction at different rotation speeds, or in different directions. The object to be polished may be polished while moving (rotating) inside the frame during the polishing process.

[0051] Slurry is a mixture of chemical components such as water, oxidizing agents such as hydrogen peroxide, additives, and abrasives (polishing particles; e.g., SiC, SiO 2 , Al 2 O 3 , CEO 2 ) etc.

[0052] [End point detection process] The method for manufacturing a polished workpiece according to the present embodiment includes an end point detection step in which the end point is detected by a torque method in the polishing step. As the end point detection method by the torque method, a conventionally known method can be specifically used. FIG. 2 shows a schematic diagram of the end point detection method by the torque method. This schematic diagram shows a chemical mechanical polishing process in which a target film on the surface of the wafer W is polished and flattened by pressing a wafer W held by a top ring 21 onto a polishing pad 10 attached on a table 22 while flowing a slurry (not shown). The polishing device 20 is equipped with a film thickness detection sensor 23 of a torque detection method around the top ring 22 in order to perform an end check and end the process with high accuracy. The wafer W has a polishing target film W1 and a stopper film W2 arranged on the underside of the polishing target film.

[0053] The polishing target film W1 and the stopper film W2 are exemplified by a silicon oxide film and a silicon nitride film.

[0054] In the torque method, a change in the friction coefficient between the wafer W and the polishing pad 10 is detected as a change in the torque of the rotation shaft of the top ring 21 or the table 22. The torque change can be detected, for example, by measuring the drive motor current of the rotation shaft of the top ring 21 or the table 22. More specifically, as shown in FIG. 3, when the film W1 to be polished is removed (STEP 1), the stopper film W2 underneath is exposed and a torque change is detected (STEP 2). In the torque method, the end point is detected by detecting this torque change. Note that in the torque method, the torque change is likely to depend on the selection of the slurry, so it is preferable to select the slurry in advance from the viewpoint of accurate end point detection. EXAMPLES

[0055] The present invention will be described in more detail below using examples and comparative examples, but the present invention is not limited to the following examples.

[0056] Example 1 A prepolymer containing an adduct of 2,4-tolylene diisocyanate and polyoxytetramethylene glycol was added with ammonium polyacrylate (number average molecular weight 1000) as an interacting compound in an amount of 0.5% by weight relative to the total amount of resin, and 3,3'-dichloro-4,4'-diaminodiphenylmethane was added as a curing agent and cured to form a polishing layer. The base layer was obtained by impregnating a nonwoven fabric made of polyethylene fibers with a polyurethane resin solution, followed by wet coagulation and drying. The base layer was attached to the polishing layer with a double-sided tape having a hot-melt adhesive layer to obtain the polishing pad of Example 1.

[0057] (Examples 2 to 6) Polishing pads of Examples 2 to 6 were obtained by the same manufacturing method as in Example 1, except that the type and amount of the interacting compound were changed as shown in Table 1.

[0058] Comparative Example 1 A polishing pad of Comparative Example 1 was obtained by the same manufacturing method as in Example 1, except that ammonium polyacrylate (number average molecular weight 1000), which is an interactive compound, was not used.

[0059] Comparative Example 2 A conventional polishing pad IC1000 (manufactured by Nitta Haas Corporation) was used.

[0060] (Measurement of dynamic friction coefficient) The surface of each polishing pad of the Examples and Comparative Examples was roughened for 30 minutes using a dresser equipped with a diamond grindstone of #160. After surface roughening, a sample was cut into a rectangular shape of 20 mm x 10 mm, and a reciprocating sliding friction tester (HEIDON-14D) was used to measure the resistance force while a slider was pressed against the sample with a constant load of 5 g. The slider was made of silicon oxide and silicon nitride, each with a side length of 5 mm, and moved at a speed of 1 mm / sec over a range of 12 mm. Measurements were performed by reciprocating 10 times for each sample and load, and the dynamic friction coefficient μ was calculated using the average load of the 10th time. O and μ N I asked.

[0061] [Table 1]

[0062] In all of Examples 1 to 6, the additive ammonium polyacrylate or naphthalenesulfonic acid-formaldehyde condensate specifically adsorbed to the silicon nitride film, increasing the frictional resistance of the silicon nitride film and decreasing the frictional resistance to the silicon oxide film. As a result, the dynamic friction coefficient μ O and the dynamic friction coefficient μ for silicon nitride film N Ratio to μ N / μ O was increased, and the torque type end point detection was performed with high accuracy. [Industrial Applicability]

[0063] The polishing pad of the present invention is used for polishing optical materials, semiconductor devices, glass substrates for hard disks, etc., and has industrial applicability as a pad that is particularly suitable for polishing devices in which an oxide layer, metal layer, etc. are formed on a semiconductor wafer. [Explanation of symbols]

[0064] 10: polishing pad, 11: polishing layer, 11a: polishing surface, 12: base layer, 20: polishing device, 21: top ring, 22: table, 23: film thickness detection sensor, W: wafer, W1: film to be polished, W2: stopper film

Claims

1. The polishing layer contains a water-soluble organic compound having a carboxylic acid group and / or a sulfonic acid group. Polishing pad.

2. The content of the water-soluble organic compound is 0.01 to 10% by weight based on the total amount of the polishing layer. The polishing pad of claim 1.

3. The water-soluble organic compound is at least one selected from the group consisting of poly(meth)acrylic acid, malic acid, lactic acid, tartaric acid, gluconic acid, adipic acid, naphthalenesulfonic acid-formalin condensates, laurylbenzenesulfonic acid, and salts thereof.

3. The polishing pad according to claim 1 or 2.

4. The water-soluble organic compound is ammonium polyacrylate or a naphthalenesulfonic acid-formaldehyde condensate. The polishing pad according to any one of claims 1 to 3.

5. The molecular weight of the water-soluble organic compound is 500 to 10,000. The polishing pad according to any one of claims 1 to 4.

6. The method includes a polishing step of polishing a workpiece having an oxide film and a nitride film by using the polishing pad according to any one of claims 1 to 5 to obtain a polished product, and an end point detection step of detecting an end point by a torque method during the polishing. A method for manufacturing polished workpieces.

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