JP2001358101A - Polishing pad - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a polishing pad for mechanically planarizing an insulating layer formed on a silicon substrate or the surface of a metal wiring, where sticking of dust and scratches are reduced, polishing rate is high, a global step is small, dishing of the metal wiring hardly occurs, and clogging and wearing out at the surface layer part hardly generate, with stable polishing rate. SOLUTION: A polishing pad is provided, which has micro rubber A hardness of 80 degrees or higher, the number of independent air bubbles is 150-2,500 (number/mm2), density is 0.6-0.95 (g/cm3), and equilibrium water-absorption factor is 5% or higher.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a polishing pad, and more particularly to a polishing pad for polishing a semiconductor substrate.
Further, the present invention relates to a polishing pad that can be used for chemical mechanical polishing in a step of mechanically flattening the surface of an insulating layer formed on a semiconductor substrate such as silicon or the surface of metal wiring.

[0002]

2. Description of the Related Art Large-scale integrated circuits (LSI) typified by semiconductor memories have been increasingly integrated year by year, and accordingly, the technology for manufacturing large-scale integrated circuits has been increasing. Further, with the increase in density, the number of stacked semiconductor device manufacturing locations has also increased. Due to the increase in the number of layers, unevenness on the main surface of the semiconductor wafer caused by stacking, which has not been a problem in the past, has become a problem. As a result, for example, the Nikkei Microdevice July 1994 issue 50
As described on page 57, a chemical mechanical polishing technique is used for the purpose of compensating for a lack of depth of focus at the time of exposure due to unevenness caused by laminating, or for improving wiring density by flattening a through-hole portion. The flattening of a semiconductor wafer that has been used has been studied.

In general, a chemical mechanical polishing apparatus comprises a polishing head for holding a semiconductor wafer as an object to be processed, a polishing pad for performing a polishing process on the object to be processed, and a polishing platen for holding the polishing pad. . Then, in the polishing process of the semiconductor wafer, the protruding portion of the layer on the surface of the semiconductor wafer is removed by moving the semiconductor wafer and the polishing pad relative to each other using a slurry composed of an abrasive and a chemical solution, thereby smoothing the layer on the wafer surface. It is to be. The polishing rate is substantially proportional to the relative speed and load between the semiconductor wafer and the polishing pad. Therefore, in order to uniformly polish each part of the semiconductor wafer, it is necessary to make the load applied to the semiconductor wafer uniform.

When polishing an insulating layer or the like formed on the main surface of a semiconductor wafer, if the polishing pad is soft, local flatness deteriorates. For this reason, a polyurethane foam sheet having a Shore A hardness of 90 degrees or more is currently used (Japanese Patent Application Laid-Open No. Hei 8-500622).

[0005]

However, the high-hardness polyurethane foam pad has a problem that the degree of flatness is different in portions having different densities of irregularities such as an insulating layer, and a global step is generated. There is a problem that dishing occurs in a wide area (the center of the metal wiring is lower in height than the edge). In addition, abrasives are easily adsorbed and clogging occurs immediately,
During polishing, there is a problem that the surface layer of the pad is set and the polishing rate is reduced.

[0006]

SUMMARY OF THE INVENTION An object of the present invention is to provide a polishing pad for mechanically planarizing the surface of an insulating layer or a metal wiring formed on a silicon substrate, which has a high polishing rate and a global step. An object of the present invention is to provide a polishing pad which is small in size, hardly causes dishing in metal wiring, hardly causes clogging and sag of a surface layer portion, and has a stable polishing rate.

[0007]

Means for Solving the Problems As means for solving the problems, the present invention has the following constitution. (1) The micro rubber A hardness is 80 degrees or more, the number of closed cells is in the range of 150 to 2500 cells / mm ² , the density is in the range of 0.6 to 0.95 (g / cm ³ ), and A polishing pad having an equilibrium water absorption of 5% or more. (2) The polishing pad according to (1), wherein the constituent material is mainly composed of polyurethane. (3) The polishing pad according to (1), wherein the constituent material contains a polymer polymerized from polyurethane and a vinyl compound. (4) The polishing pad according to (3), wherein a polymer polymerized from a polyurethane and a vinyl compound is integrally contained. (5) The content ratio of the polymer polymerized from the polyurethane and the vinyl compound in the polymer is 40/60 to 10 / by weight.
90. The polishing pad according to (3) or (4), wherein the polishing pad is 90. (6) The vinyl compound is characterized in that CH ₂ ＣＲCR ¹ COOR ² (R ¹ : methyl group or ethyl group, R ² : methyl group, ethyl group, propyl group or butyl group) (3)
To (5) any of the polishing pads. (7) The polishing pad according to any one of (1) to (6), wherein the average diameter of the closed cells is 20 μm to 90 μm.

[0008]

Embodiments of the present invention will be described below. First, the micro rubber A hardness referred to in the present invention will be described. This hardness refers to a value evaluated by a micro rubber hardness meter MD-1 manufactured by Kobunshi Keiki Co., Ltd. The micro rubber hardness tester MD-1 realizes the measurement of hardness of thin and small samples, which is difficult to measure with a conventional hardness tester, and is about 1/5 of a spring type rubber hardness tester (durometer) type A. Since it is designed and manufactured as a reduced model of, a measured value corresponding to the hardness of the spring type rubber hardness meter A type is obtained. The micro rubber hardness tester MD-1 has a diameter of 0.16 mm in diameter and a height of 0.5 mm. The load method is a cantilever type leaf spring. The spring load is 2.24 mN at 0 point and 3 at 100 points.
3.85 mN. Needle descent speed is 10-30mm /
The range of sec is measured by controlling with a stepping motor. In a normal polishing pad, the thickness of the polishing layer or the hard layer is less than 5 mm, and cannot be evaluated with a spring-type rubber hardness meter A because it is too thin.
D-1.

The polishing pad of the present invention needs to have a micro rubber A hardness of 80 degrees or more, preferably 90 degrees or more.
If the micro rubber A hardness is less than 80 degrees, the flatness of the local unevenness of the semiconductor substrate becomes poor, which is not preferable.

The polishing pad according to the present invention has elasticity in the thickness direction due to having closed cells, so that even if agglomerates of slurry or polishing debris are interposed between the surface to be polished and the polishing pad, the polishing pad is not damaged. This is necessary because generation can be prevented. The number of closed cells refers to the number of bubbles per 1 mm ² observed when an arbitrary cross section of the polishing pad is observed with an optical microscope or a scanning electron microscope. In the present invention, the number of closed cells is 150 to
It needs to be 2500 pieces / mm ² . Number of closed cells is 1
When the number is less than 50 pieces / mm ² or more than 2500 pieces / mm ² , the polishing rate of the polishing pad is not sufficiently increased, and dust and scratches are easily generated. The preferred number of closed cells is 250 to 1500 cells /
mm ² . A more preferred number of closed cells is 330 to
It is 1100 pieces / mm ² .

The polishing pad of the present invention has a density of 0.6 to 0.6.
It must be in the range of 0.95 (g / cm ³ ). Density is 0.
When it is less than 6 (g / cm ³ ), the flatness of the local unevenness is poor, and the global step is undesirably large. If the density exceeds 0.95 (g / cm ³ ), scratches are likely to occur, which is not preferable. A more preferred density is in the range of 0.65 to 0.92 (g / cm ³ ).
Further, a more preferable density is 0.70 to 0.88 (g / c
m ³ ).

The equilibrium moisture content of the polishing pad of the present invention refers to a value determined by the following method.

The test piece is a square with a side of 50 mm,
A plate having a thickness of 1.0 to 2.0 mm is prepared, dried in a thermostat kept at 50 ° C. for 24 hours, and then allowed to cool to room temperature in a desiccator. The mass of the test piece is measured to 0.1 mg, and this is defined as M1. Next, the test piece is immersed in a container containing water kept at 23 ° C. After a lapse of 30 days, the test piece is taken out of the water, the water adhering to the test piece surface is wiped off with a filter paper, and then the mass of the test piece is measured to 0.1 mg, which is defined as M2. Note that this measurement was taken 1 hour after removing from water.
Do it within minutes. The value obtained by the formula (I), that is, the ratio of the original mass of the test piece to the mass increase before and after water absorption is defined as the equilibrium water absorption.

(M2−M1) / M1 × 100 (%): (I) The equilibrium water absorption must be 5% or more. If the equilibrium water absorption is less than 5%, dust is liable to adhere to the wafer and scratches are likely to occur, which is not preferable. A more preferable equilibrium water absorption is 7% or more.

The polyurethane in the polishing pad of the present invention is a polymer synthesized based on a polyaddition reaction or polymerization reaction of polyisocyanate. The compound used as the symmetry of the polyisocyanate is an active hydrogen compound, that is, a compound containing two or more polyhydroxy or amino groups. Examples of the polyisocyanate include, but are not limited to, tolylene diisocyanate, diphenylmethane diisocyanate, naphthalene diisocyanate, tolidine diisocyanate, hexamethylene diisocyanate, and isophorone diisocyanate. Polyol is typical as polyhydroxy, but as polyol, polyether polyol, polypropylene glycol, polytetramethylene ether glycol, epoxy resin-modified polyol,
Examples include polyester polyol, acrylic polyol, polybutadiene polyol, and silicone polyol. Among them, tolylene diisocyanate, diphenylmethane diisocyanate as polyisocyanate,
As the polyol, a polyurethane obtained in combination with polypropylene glycol and polytetramethylene ether glycol is preferable because it has excellent moldability and is widely used.

The vinyl compound in the present invention is a compound having a vinyl group having a carbon-carbon double bond. Specifically, methyl methacrylate, ethyl methacrylate, propyl methacrylate, n-butyl methacrylate, isobutyl methacrylate, methyl (α-ethyl) acrylate, ethyl (α-ethyl) acrylate, propyl (α
-Ethyl) acrylate, butyl (α-ethyl) acrylate, 2-ethylhexyl methacrylate, isodecyl methacrylate, n-lauryl methacrylate, 2-
Hydroxyethyl methacrylate, 2-hydroxypropyl methacrylate, 2-hydroxyethyl acrylate, 2-hydroxypropyl acrylate, 2-hydroxybutyl methacrylate, dimethylaminoethyl methacrylate, diethylaminoethyl methacrylate, methacrylic acid, glycidyl methacrylate, ethylene glycol dimethacrylate, fumaric acid , Dimethyl fumarate, diethyl fumarate, dipropyl fumarate, maleic acid, dimethyl maleate, diethyl maleate, dipropyl maleate, acrylonitrile, acrylamide,
Examples thereof include vinyl chloride, styrene, and α-methylstyrene. Among them, preferred vinyl compounds are methyl methacrylate, ethyl methacrylate, propyl methacrylate, n-butyl methacrylate, isobutyl methacrylate, methyl (α-ethyl) acrylate, ethyl (α-ethyl) acrylate, propyl (α-ethyl)
Acrylate and butyl (α-ethyl) acrylate. The polymer polymerized from the vinyl compound in the present invention is a polymer obtained by polymerizing the vinyl compound, and specifically, polymethyl methacrylate, polyethyl methacrylate, polypropyl methacrylate, poly (n-butyl) (Methacrylate), polyisobutyl methacrylate, polymethyl (α-ethyl) acrylate, polyethyl (α-ethyl) acrylate, polypropyl (α-ethyl) acrylate, polybutyl (α-ethyl) acrylate, poly (2-ethylhexyl methacrylate), polyiso Decyl methacrylate, poly (n-
Lauryl methacrylate), poly (2-hydroxyethyl methacrylate), poly (2-hydroxypropyl methacrylate), poly (2-hydroxyethyl acrylate), poly (2-hydroxypropyl acrylate), poly (2-hydroxybutyl methacrylate),
Polydimethylaminoethyl methacrylate, polydiethylaminoethyl methacrylate, polymethacrylic acid, polyglycidyl methacrylate, polyethylene glycol dimethacrylate, polyfumaric acid, polydimethyl dimethyl, diethyl polyfumarate, dipropyl polyfumarate,
Examples thereof include polymaleic acid, dimethyl polymaleate, diethyl polymaleate, dipropyl polymaleate, polyacrylonitrile, polyacrylamide, polyvinyl chloride, polystyrene, and poly (α-methylstyrene). Among them, preferred polymers are polymethyl methacrylate, polyethyl methacrylate, polypropyl methacrylate, poly (n-butyl methacrylate), polyisobutyl methacrylate, polymethyl (α-ethyl) acrylate, polyethyl (α-ethyl) acrylate, polypropyl (Α-ethyl) acrylate and polybutyl (α-ethyl) acrylate can increase the hardness of the polishing pad and improve the flattening characteristics.

The content ratio of the polyurethane and the vinyl compound in the polymer obtained by polymerizing the polyurethane and the vinyl compound in the present invention is preferably 60/40 to 10/90 by weight. When the content ratio of the vinyl compound is less than 40 in weight ratio, the hardness of the polishing pad becomes low, which is not preferable. If the content ratio exceeds 90, the elasticity of the pad is impaired, which is not preferable. The content of the polymer polymerized from the polyurethane or vinyl compound in the polishing pad can be measured by pyrolysis gas chromatography / mass spectrometry of the polishing pad.
Apparatuses that can be used in this method include a double-shot pyrolyzer "PY-2010D" (manufactured by Frontier Laboratories) as a pyrolyzer and "TRIO-1" (manufactured by VG) as a gas chromatograph / mass spectrometer. Can be.

In the present invention, the expression that the polymer which is polymerized from the polyurethane and the vinyl compound is contained integrally means that the polyurethane and the polymer which is polymerized from the vinyl compound are contained in a separated state. However, when quantitatively expressed, various spots of the layer having essentially the polishing function in the pad have a spot size of 50%.
The infrared spectrum observed with a micrometer infrared spectrometer has an infrared absorption peak of polyurethane and an infrared absorption peak of a polymer polymerized from a vinyl compound. It is to be. As a micro-infrared spectrometer used here, SPECTRA-
"IRμs" manufactured by TECH may be mentioned.

The average cell diameter of the closed cells of the polishing pad of the present invention is preferably in the range of 20 to 90 μm. If the average bubble diameter is less than 20 μm, the polishing rate is not sufficiently high, which is not preferable. If the average bubble diameter exceeds 90 μm, the global flatness becomes poor, which is not preferable.

The method for preparing the polishing pad of the present invention is preferably
A preferable method is that the number of closed cells is 150 to 250 in advance.
0 (pcs / mm^Two) And a density of 0.6 to 0.9.
5 (g / cm^Three) And foaming with an equilibrium water absorption of 5% or more
After swelling the vinyl compound on the polyurethane sheet,
For polymerizing vinyl compounds in foamed polyurethane sheet
The method uses polyurethane with a structure with closed cells and vinylation.
Polishing in which the polymer polymerized from the compound is contained integrally
A pad can be created, and the resulting polishing pad provides local irregularities
Is preferable because it can reduce the flatness of the
No. A more preferable method is that the average bubble diameter is 2 in advance.
It has closed cells of 0 to 90 μm and the number of closed cells is 250 to
1500 (pcs / mm^Two) And a density of 0.6 to
0.95 (g / cm ^Three))
After swelling the carbonyl compound, the foamed polyurethane sheet
The method of polymerizing vinyl compounds with
Polymerized from polyurethane and vinyl compounds in a structure
Polishing pad with integrated body can be made,
Polished pad with local unevenness flatness and global step
This is preferable because the difference can be reduced. Foamed poly in the present invention
Depending on hardness, cell diameter and expansion ratio, polyurethane sheet
Isocyanates and polyols and catalysts, foam stabilizers, foaming
It is necessary to determine the combination of the agents and the optimal amount. Foamed poly
As the urethane sheet, the above-mentioned polyurethane is foamed.
What has been used is preferably used.

As a method of polymerizing the vinyl compound in the foamed polyurethane sheet after the vinyl compound is swollen in the foamed polyurethane sheet, the vinyl compound is swollen together with a photodegradable radical initiator and then exposed to light for polymerization. Examples of the method include a method of swelling a vinyl compound together with a thermally decomposable radical initiator and then applying heat to polymerize the same, and a method of swelling the vinyl compound and then polymerizing it by emitting an electron beam or radiation.

The polishing pad of the present invention may contain abrasive grains. Examples of the abrasive include a silica-based abrasive, an aluminum oxide-based abrasive, and a cerium oxide-based abrasive. The method for preparing the polishing pad of the present invention containing abrasive grains is such that the foamed polyurethane sheet described above contains abrasive grains in advance, and the vinyl compound is swollen into the abrasive grain-containing foamed polyurethane sheet by the above method. As a method of polymerizing a vinyl compound in a foamed polyurethane sheet, after swelling the vinyl compound with a photodegradable radical initiator, a method of polymerizing by exposure to light, or a method of swelling the vinyl compound with a thermally decomposable radical initiator Then, a method of polymerizing by applying heat or a method of swelling a vinyl compound and then radiating an electron beam or radiation to polymerize.

The polishing pad obtained by the present invention can be used as a composite polishing pad by laminating it with a cushion sheet having cushioning properties. A semiconductor substrate has slightly larger undulations apart from local irregularities, and a polishing sheet is often polished with a cushion sheet below a hard polishing pad (on the polishing platen side) as a layer for absorbing the undulations.

Using the polishing pad of the present invention, silica slurry, aluminum oxide slurry,
Using a cerium oxide-based slurry or the like, unevenness of an insulating film and unevenness of a metal wiring on a semiconductor wafer can be locally flattened, global steps can be reduced, and dishing can be suppressed. As a specific example of the slurry, CAB-O-SPIRESE S for CMP manufactured by CABO
CA-1, CAB-O-SPERSE SC-1 for CMP
12, SEMI-SPERSE AM100 for CMP
SEMI-SPERSE AM100C for CMP, CM
SEMI-SPERSE 12 for P, SEMI for CMP
-SPERSE 25, SEMI-SPERS for CMP
EW2000, SEMI-SPERSE W for CMP
-A400 and the like, but are not limited thereto.

The object of the polishing pad of the present invention is an insulating layer formed on a semiconductor wafer or a surface of a metal wiring. As the insulating layer, an interlayer insulating film of a metal wiring, a lower insulating film of a metal wiring, Examples of the shallow trench isolation used for element isolation include aluminum, tungsten, copper, and the like, and structurally include damascene, dual damascene, and plug. When copper is used as the metal wiring, a barrier metal such as silicon nitride is also polished. At present, silicon oxide is mainly used as an insulating film, but a low dielectric constant insulating film is used due to a problem of delay time. The low-dielectric-constant insulating film is softer and more brittle than silicon oxide, but the polishing pad of the present invention can be polished in a state where scratches are relatively difficult to enter. It can also be used for polishing magnetic heads, hard disks, sapphire, etc. other than semiconductor wafers.

The surface shape of the polishing pad of the present invention is used in a shape that a normal polishing pad can take, such as a grooved shape, a dimple shape, a spiral shape, and a concentric shape, in order to suppress the hydroplane phenomenon. The polishing pad is used in the form of a disk, but it may be used in the form of a belt depending on the type of polishing machine.

The polishing pad of the present invention is fixed to a polishing platen (platen) of a polishing machine. The wafer is fixed to a wafer holding sample stage (carrier) by a vacuum chuck method. The polishing platen is rotated, and the wafer holding sample table is rotated in the same direction, and pressed against the polishing pad. At this time, the slurry is supplied from a position where the slurry enters between the polishing pad and the semiconductor wafer. The supply amount of the slurry is 0.005 to 0.15 per 1 cm ² area of the polishing pad.
(Cc / min) is the optimal range. If the supply amount of the slurry is less than 0.005 (cc / min), a sufficient lubrication effect of the slurry cannot be obtained, so that the surface of the semiconductor wafer is scratched or the semiconductor wafer rotates smoothly on the polishing pad. This is not preferable because it hardly occurs and the in-plane uniformity is impaired. Supply amount of slurry is 0.15 (cc / min)
In the case where it exceeds, a slurry liquid film is likely to be formed between the semiconductor wafer and the surface of the polishing pad, and the flattening characteristics deteriorate, which is not preferable. The rotational speed of the polishing table is such that the linear velocity of the polishing table at the center position of the semiconductor wafer is 2000 to 50.
It is preferably in the range of 00 (cm / min). When the linear velocity of the polishing platen is lower than 2000 (cm / min), the flattening rate becomes slow, which is not preferable. If the linear velocity of the polishing platen exceeds 5000 (cm / min), scratches are likely to occur, which is not preferable. The pressing pressure is controlled by controlling the force applied to the wafer holding sample stage. A pressing pressure of 0.01 to 0.1 MPa is preferable because local flatness can be obtained. However, depending on the polishing machine, a high-speed, low-pressure platen system has also been developed, and it is not impossible to use it under conditions other than the above polishing conditions.

The surface of the polishing pad of the present invention is usually dressed with a conditioner in which diamond abrasive grains are electrodeposited before polishing. As a method of dressing, it is possible to use either batch dressing performed before polishing or in-situ dressing performed simultaneously with polishing.

[0029]

The present invention will be described below in further detail with reference to examples. In this example, each characteristic was measured by the following method. 1. Micro rubber A hardness: Polymer Instruments Co., Ltd. (Location:
It is measured with a micro rubber hardness tester “MD-1” from Kamimyo-ku, Kyoto.

The configuration of the micro rubber hardness meter "MD-1" is as follows. 1.1 Sensor part (1) Load method: cantilever leaf spring (2) Spring load: 0 point / 2.24 gf. 100 points / 33.85 gf (3) Spring load error: ± 0.32 gf (4) Needle dimensions: Diameter: 0.16 mm cylinder. Height: 0.5 mm (5) Displacement detection method: strain gauge type (6) Pressing leg dimensions: outer diameter 4 mm inner diameter 1.5 mm 1.2 sensor driving unit (1) Driving method: vertical drive by stepping motor.
Lowering speed control by air damper (2) Vertical movement stroke: 12 mm (3) Lowering speed: 10 to 30 mm / sec (4) Height adjustment range: 0 to 67 mm (distance between sample table and sensor pressing surface) 1.3 Sample stand (1) Sample stage dimensions: diameter 80 mm (2) Fine movement mechanism: Fine movement by XY table and micrometer head. Stroke: 15 mm for both X and Y axes. (3) Level adjuster: Main body leg for level adjustment and round level. 2. Test wafer for dust and scratch evaluation: 4-inch silicon wafer with oxide film (oxide film thickness: 2 μm) Test wafer for global level difference evaluation: 4 with oxide film
10 mm on inch silicon wafer (oxide film thickness: 2 μm)
Place the corner die. A mask exposure is performed using a photoresist, and a line having a width of 20 μm and a height of 0.7 μm and a space of 230 μm are arranged on the left half by line and space in a 10 mm square die by RIE.
A line having a width of 30 μm and a height of 0.7 μm is arranged in a line and space on the right half in a space of 20 μ. Thus, a test wafer for global step evaluation was prepared.

4. Test wafer for dishing evaluation of tungsten wiring: 4-inch silicon wafer with oxide film (oxide film thickness: 2 μm), 100 μm width and 0.7 μ depth
m grooves are formed at intervals of 100 μm. A tungsten film having a thickness of 2 μm was formed thereon by sputtering to prepare a test wafer for evaluating dishing of tungsten wiring.

5. Polishing pad and polishing machine: 1.2m thickness
A circular polishing layer having a diameter of 38 m and a diameter of 38 cm was prepared, and the surface was subjected to so-called XY groove processing (grid-like groove processing) having a width of 2.0 mm, a depth of 0.5 mm, and a pitch of 15 mm. A polishing machine (Lapmaster SFT, L / L)
As a cushion layer, "Suba400" manufactured by Rodale was applied to the surface plate of M-15E), and a double-sided adhesive tape ("442J" manufactured by 3M) was applied thereon. Conditioner of Asahi Diamond Industrial Co., Ltd. (“CMP-
M ", diameter 14.2 cm) and a pressing pressure of 0.0
4MPa, rotated in the same direction at a platen rotation speed of 25rpm and a conditioner rotation speed of 25rpm.
The polishing pad was conditioned for 5 minutes while being supplied in minutes. The polishing pad is washed for 2 minutes while flowing 100 cc / min of pure water through the polishing machine. Then, a test wafer for dust and scratch evaluation or a test wafer for global level difference evaluation is set in the polishing machine, and a cabot having a working concentration described in the manual is used. While supplying the slurry (“SC-1”) manufactured by the company in a predetermined supply amount onto the polishing pad, the pressing pressure was 0.04MP.
a, The platen rotation speed was 45 rpm (linear velocity at the center of the wafer was 3000 (cm / min)), the semiconductor wafer holding sample table was rotated in the same direction at a rotation speed of 45 rpm, and polishing was performed for a predetermined time. The surface of the semiconductor wafer was not dried, and the surface of the wafer was washed with a polyvinyl alcohol sponge while immediately applying pure water, and dried by blowing dry compressed air. The test wafer for dust and scratch evaluation was inspected for dust of 0.5 μm or more with a dust inspection device WM-3 manufactured by Topcon, and then inspected for scratches with a microscope. Lambda Ace (“VM”
-2000 "), and the difference between the thicknesses was evaluated as a global step. The same conditioning as described above was performed, and a test wafer for evaluating tungsten wiring dishing was set on a polishing machine and used as described in the instruction manual. Concentration Cabot slurry (“SEMI-SPERSE
WA-400 ”) and an oxidizing agent manufactured by Cabot (“ SEM
I-SPERSE FE-400 ″) at a pressure of 0.04 MPa and a platen rotation speed of 45 r while supplying a slurry solution mixed at 1: 1 on the polishing pad in a predetermined supply amount.
pm (linear velocity at the center of the wafer is 3000 (cm /
Min)), the semiconductor wafer holding sample stage was rotated in the same direction at a rotation speed of 45 rpm, and polishing was performed for a predetermined time. The surface of the semiconductor wafer was not dried, and the surface of the wafer was washed with a polyvinyl alcohol sponge while immediately applying pure water, and dried by blowing dry compressed air. The dishing state of the tungsten surface was measured with an ultra-depth shape measuring microscope “VK-8500” manufactured by Keyence Corporation.

Example 1 35 parts by weight of polypropylene glycol, 40 parts by weight of diphenylmethane diisocyanate, 0.5 part by weight of water, 0.3 part by weight of triethylamine, 1.7 parts by weight of a silicone foam stabilizer, and 0.09 parts by weight of tin octylate Are mixed by a RIM molding machine, and are discharged into a mold to perform pressure molding to form a thickness of 2.2.
mm polyurethane foam sheet (micro rubber A hardness =
47 degrees, density: 0.70 (g / cm ³ ), closed cell average diameter: 5
2 μm, number of bubbles: 279 / mm ² , equilibrium water absorption: 21
%). The foamed polyurethane sheet was immersed in methyl methacrylate containing 0.1 part by weight of azobisisobutylnitrile for 35 minutes. The foamed polyurethane sheet swollen with methyl methacrylate was sandwiched between glass plates, heated at 65 ° C. for 6 hours, and then heated at 100 ° C. for 3 hours. After heating, it was removed from the glass plate and vacuum dried at 50 ° C. The obtained hard foam sheet was ground on both sides to produce a polishing pad having a thickness of 1.2 mm. The obtained polishing pad had a micro rubber A hardness of 93 degrees and a density of 0.7.
6. Closed cell average diameter: 64 μm, number of bubbles: 171 / m
m ² , D hardness: 54 degrees, and the content of polymethyl methacrylate in the polishing pad was 60% by weight. The resulting polishing pad had an equilibrium water absorption of 8.1%. A cushion layer “Suba400” was bonded to the polishing pad to produce a composite polishing pad. Attach the test wafer for global level difference evaluation to the polishing head of the polishing machine.
The composite polishing pad was fixed to a platen of a polishing machine by rotating the polishing pad at 5 rpm, and was rotated in the same direction as the polishing head at 45 rpm.
Minute (polishing pad 1cm ² area per 0.031cc /
) And polishing was performed at a polishing pressure of 0.04 MPa. 20 μm test wafer for global level difference evaluation
The global step between the width wiring region and the 230 μm width wiring region became 0.2 μm, and the polishing time was 4 minutes. Further, the test wafer for dust and scratch evaluation was attached to the polishing head of the polishing machine and rotated at 45 rpm, and the composite polishing pad was fixed to the platen of the polishing machine, and rotated at 45 rpm in the same direction as the rotation direction of the polishing head. 35 cc / min.
Polishing was performed at a polishing pressure of 0.04 MPa while supplying at a rate of 0.031 cc / min per cm ² area). The number of dusts on the wafer was 3, and no scratch was observed. Also, a test wafer for dishing evaluation of tungsten wiring was attached to a polishing head of a polishing machine at 45 rpm.
And the composite polishing pad is fixed to a platen of a polishing machine, and rotated at 45 rpm in the same direction as the rotation direction of the polishing head.
5 cc / min (0.031 per 1 cm ² area of polishing pad)
(cc / min) and polishing was performed at a polishing pressure of 0.04 MPa. The dishing depth at the center of the tungsten wiring (100 μm width) when the surface of the oxide film is exposed is 0.1 mm.
03 μm.

Example 2 30 parts by weight of polypropylene glycol, 40 parts by weight of diphenylmethane diisocyanate, 0.6 parts by weight of water, 0.3 parts by weight of triethylamine, 1.7 parts by weight of a silicone foam stabilizer, and 0.09 parts by weight of tin octylate Are mixed in a RIM molding machine, and are discharged into a mold to perform pressure molding, and a thickness of 2.2 is obtained.
mm polyurethane foam sheet (micro rubber A hardness =
50 degrees, density: 0.80, closed cell average diameter: 29 μm,
(The number of air bubbles: 688 / mm ² , equilibrium water absorption: 23%). The foamed polyurethane sheet was immersed in methyl methacrylate containing 0.1 part by weight of azobisisobutylnitrile for 35 minutes. The foamed polyurethane sheet swollen with methyl methacrylate was sandwiched between glass plates, heated at 65 ° C. for 6 hours, and then heated at 100 ° C. for 3 hours. After heating, it was removed from the glass plate and vacuum dried at 50 ° C. The obtained rigid foam sheet was ground on both sides to have a thickness of 1.
A 2 mm polishing pad was prepared. The resulting polishing pad had a micro rubber A hardness of 96 degrees, a density of 0.81, an average closed cell diameter of 40 μm, a number of bubbles: 363 / mm ² , and a D hardness of 57 degrees. The methyl methacrylate content was 60% by weight. The resulting polishing pad had an equilibrium water absorption of 7.5%. A cushion layer “Suba400” was bonded to the polishing pad to produce a composite polishing pad. The test wafer for global level difference evaluation was attached to a polishing head of a polishing machine and rotated at 45 rpm, the composite polishing pad was fixed to a platen of the polishing machine, and rotated at 45 rpm in the same direction as the rotation direction of the polishing head to obtain a slurry “SC- Polishing was performed at a polishing pressure of 0.04 MPa while supplying 1 ″ at 35 cc / min (0.031 cc / min per 1 cm ² area of the polishing pad). The global step between the 20 μm-wide wiring region and the 230 μm-wide wiring region of the test wafer for global step evaluation became 0.2 μm, and the polishing time was 4 minutes. Further, the test wafer for dust and scratch evaluation was attached to the polishing head of the polishing machine and rotated at 45 rpm, and the composite polishing pad was fixed to the platen of the polishing machine, and rotated at 45 rpm in the same direction as the rotation direction of the polishing head. Company slurry ”
SC-1 "is supplied at a rate of 35 cc / min (0.031 cc / min per 1 cm ² area of the polishing pad) while the polishing pressure is set at 0.1 cc / min.
Polishing was performed at 04 MPa. The number of dust on the wafer is 2
And no scratch was observed. Further, a test wafer for evaluating tungsten wiring dishing was attached to a polishing head of a polishing machine and rotated at 45 rpm, and the composite polishing pad was fixed to a platen of the polishing machine to be fixed at 45 rpm.
m, the polishing head is rotated in the same direction as the rotation direction, and polishing is performed at a polishing pressure of 0.04 MPa while supplying a slurry for tungsten made by Cabot at a rate of 35 cc / min (0.031 cc / min per 1 cm ² area of the polishing pad). did.
Tungsten wiring (100μ) when the oxide film surface is exposed
(m width) The dishing depth at the center was 0.03 μm.

Example 3 30 parts by weight of polypropylene glycol, 40 parts by weight of diphenylmethane diisocyanate, 0.7 parts by weight of water, 0.3 parts by weight of triethylamine, 1.7 parts by weight of a silicone foam stabilizer, and 0.09 parts by weight of tin octylate Are mixed in a RIM molding machine, and are discharged into a mold to perform pressure molding, and a thickness of 2.2 is obtained.
mm polyurethane foam sheet (micro rubber A hardness =
46 degrees, density: 0.88, closed cell average diameter: 29 μm,
(The number of bubbles: 697 / mm ² , equilibrium water absorption: 24%). The foamed polyurethane sheet was immersed in methyl methacrylate to which 0.1 parts by weight of azobisisobutylnitrile was added for 50 minutes. The foamed polyurethane sheet swollen with methyl methacrylate was sandwiched between glass plates, heated at 65 ° C. for 6 hours, and then heated at 100 ° C. for 3 hours. After heating, it was removed from the glass plate and vacuum dried at 50 ° C. The obtained rigid foam sheet was ground on both sides to have a thickness of 1.
A 2 mm polishing pad was prepared. The resulting polishing pad had a micro rubber A hardness of 98 degrees, a density of 0.84, an average closed cell diameter of 42 μm, the number of bubbles: 329 / mm ² , and a D hardness of 56 degrees. The methyl methacrylate content was 70% by weight. The obtained polishing pad had an equilibrium water absorption of 7.8%. A cushion layer “Suba400” was bonded to the polishing pad to produce a composite polishing pad. The test wafer for global level difference evaluation was attached to a polishing head of a polishing machine and rotated at 45 rpm, the composite polishing pad was fixed to a platen of the polishing machine, and rotated at 45 rpm in the same direction as the rotation direction of the polishing head to obtain a slurry “SC- Polishing was performed at a polishing pressure of 0.04 MPa while supplying 1 ″ at 35 cc / min (0.031 cc / min per 1 cm ² area of the polishing pad). The global step between the 20 μm-wide wiring region and the 230 μm-wide wiring region of the test wafer for global step evaluation became 0.2 μm, and the polishing time was 4 minutes. Further, the test wafer for dust and scratch evaluation was attached to the polishing head of the polishing machine and rotated at 45 rpm, and the composite polishing pad was fixed to the platen of the polishing machine, and rotated at 45 rpm in the same direction as the rotation direction of the polishing head. Company slurry ”
SC-1 "is supplied at a rate of 35 cc / min (0.031 cc / min per 1 cm ² area of the polishing pad) while the polishing pressure is set at 0.1 cc / min.
Polishing was performed at 04 MPa. 5 dust on wafer
And no scratch was observed. Further, a test wafer for evaluating tungsten wiring dishing was attached to a polishing head of a polishing machine and rotated at 45 rpm, and the composite polishing pad was fixed to a platen of the polishing machine to be fixed at 45 rpm.
m, the polishing head is rotated in the same direction as the rotation direction, and polishing is performed at a polishing pressure of 0.04 MPa while supplying a slurry for tungsten made by Cabot at a rate of 35 cc / min (0.031 cc / min per 1 cm ² area of the polishing pad). did.
Tungsten wiring (100μ) when the oxide film surface is exposed
(m width) The dishing depth at the center was 0.03 μm.

Example 4 30 parts by weight of polypropylene glycol, 40 parts by weight of diphenylmethane diisocyanate, 0.5 part by weight of water, 0.3 part by weight of triethylamine, 1.7 parts by weight of a silicone foam stabilizer, and 0.09 parts by weight of tin octylate Are mixed in a RIM molding machine, and are discharged into a mold to perform pressure molding, and a thickness of 2.2 is obtained.
mm polyurethane foam sheet (micro rubber A hardness =
58 degrees, density: 0.90, closed cell average diameter: 26 μm,
(The number of bubbles: 534 / mm ² , equilibrium water absorption: 21%). The foamed polyurethane sheet was immersed in methyl methacrylate containing 0.1 part by weight of azobisisobutylnitrile for 28 minutes. The foamed polyurethane sheet swollen with methyl methacrylate was sandwiched between glass plates, heated at 65 ° C. for 6 hours, and then heated at 100 ° C. for 3 hours. After heating, it was removed from the glass plate and vacuum dried at 50 ° C. The obtained rigid foam sheet was ground on both sides to have a thickness of 1.
A 2 mm polishing pad was prepared. The resulting polishing pad had a micro rubber A hardness of 100 degrees, a density of 0.91, a closed cell average diameter of 37 μm, a number of bubbles of 370 / mm ² , and D
Hardness: 67 degrees, and the content of polymethyl methacrylate in the polishing pad was 60% by weight. The obtained polishing pad had an equilibrium water absorption of 7.8%. A cushion layer “Suba400” was bonded to the polishing pad to produce a composite polishing pad. Attach the test wafer for global level difference evaluation to the polishing head of the polishing machine at 45 rpm
The composite polishing pad is fixed to a platen of a polishing machine, and is rotated at 45 rpm in the same direction as the rotation direction of the polishing head. The slurry “SC-1” is 35 cc / min (0.031 cc per 1 cm ^{2 of} polishing pad area). / Min) while polishing at a polishing pressure of 0.04 MPa. The global step between the 20 μm-wide wiring region and the 230 μm-wide wiring region of the test wafer for global step evaluation is 0.2 μm.
Polishing time was 4 minutes. Further, the test wafer for dust and scratch evaluation was attached to the polishing head of the polishing machine and rotated at 45 rpm, and the composite polishing pad was fixed to the platen of the polishing machine, and rotated at 45 rpm in the same direction as the rotation direction of the polishing head. Polishing was performed at a polishing pressure of 0.04 MPa while supplying a slurry “SC-1” manufactured by the company at a rate of 35 cc / min (0.031 cc / min per 1 cm ² area of the polishing pad). The number of dusts on the wafer was 3, and no scratch was observed. Also,
A test wafer for evaluating tungsten wiring dishing was attached to a polishing head of a polishing machine and rotated at 45 rpm to fix the composite polishing pad to a platen of the polishing machine.
At 5 rpm, the polishing head is rotated in the same direction as the rotation direction, and 35 cc of Cabot tungsten slurry is supplied.
/ Min (0.031 cc / per 1 cm ² area of polishing pad)
) And polishing was performed at a polishing pressure of 0.04 MPa. The dishing depth at the center of the tungsten wiring (100 μm width) when the oxide film surface is exposed is 0.03
μm.

Example 5 30 parts by weight of polypropylene glycol, 40 parts by weight of diphenylmethane diisocyanate, 0.55 parts by weight of water, 0.3 parts by weight of triethylamine, 1.7 parts by weight of a silicone foam stabilizer, and 0.09 parts by weight of tin octylate Is mixed by a RIM molding machine, and is discharged into a mold to perform pressure molding.
2 mm foamed polyurethane sheet (micro rubber A hardness = 48 degrees, density: 0.80, closed cell average diameter: 34μ)
m, number of bubbles: 584 / mm ² , equilibrium water absorption: 19%)
Was prepared. The foamed polyurethane sheet was immersed in methyl methacrylate containing 0.1 part by weight of azobisisobutylnitrile for 15 minutes. The foamed polyurethane sheet swollen with methyl methacrylate was sandwiched between glass plates and heated at 65 ° C. for 24 hours, and then heated at 100 ° C. for 3 hours. After heating, it was removed from the glass plate and vacuum dried at 50 ° C. The obtained hard foam sheet was ground on both sides to produce a polishing pad having a thickness of 1.2 mm. The resulting polishing pad had a micro rubber A hardness of 94 degrees and a density of 0.
845, average diameter of closed cells: 34 μm, number of cells: 429 / mm ² , D hardness: 49 degrees, and the content of polymethyl methacrylate in the polishing pad was 43% by weight. The resulting polishing pad had an equilibrium water absorption of 8.1%. A cushion layer “Suba400” was bonded to the polishing pad to produce a composite polishing pad. The test wafer for global level difference evaluation was attached to a polishing head of a polishing machine and rotated at 45 rpm, the composite polishing pad was fixed to a platen of the polishing machine, and rotated at 45 rpm in the same direction as the rotation direction of the polishing head to obtain a slurry “SC- 1 "to 35
cc / min (0.031 c per 1 cm ² area of polishing pad)
c / min), and polishing was performed at a polishing pressure of 0.04 MPa. 20 test wafers for global level difference evaluation
The global step between the μm-width wiring region and the 230 μm-width wiring region became 0.2 μm, and the polishing time was 4 minutes. Further, a test wafer for dust and scratch evaluation was attached to a polishing head of a polishing machine and rotated at 45 rpm, and the composite polishing pad was fixed to a platen of the polishing machine to be fixed at 45 rpm.
To rotate in the same direction as the rotation direction of the polishing head, and polishing at a polishing pressure of 0.04 MPa while supplying Cabot's slurry “SC-1” at 35 cc / min (0.031 cc / min per 1 cm ² area of the polishing pad). Was carried out. The number of dusts on the wafer was 2, and no scratch was observed. In addition, a test wafer for evaluating tungsten wiring dishing was attached to a polishing head of a polishing machine for 45 r.
, the composite polishing pad is fixed to a platen of a polishing machine, and rotated at 45 rpm in the same direction as the rotation direction of the polishing head. The slurry for tungsten made by Cabot Co., Ltd. is 35 cc / min (0.1 cm per area of polishing pad 1 cm ²⁾ . 0
Polishing pressure 0.04MPa while supplying at 31cc / min)
Was polished. The dishing depth at the center of the tungsten wiring (100 μm width) when the oxide film surface was exposed was 0.03 μm.

Example 6 30 parts by weight of polypropylene glycol, 40 parts by weight of diphenylmethane diisocyanate, 0.3 part by weight of water, 0.3 part by weight of triethylamine, 1.7 parts by weight of a silicone foam stabilizer, and 0.09 parts by weight of tin octylate Are mixed in a RIM molding machine, and are discharged into a mold to perform pressure molding, and a thickness of 2.2 is obtained.
mm polyurethane foam sheet (micro rubber A hardness =
50 °, density: 0.77, closed cell average diameter: 32 μm,
(The number of air bubbles: 625 / mm ² , equilibrium water absorption: 22%). The foamed polyurethane sheet was immersed in methyl methacrylate to which 0.1 parts by weight of azobisisobutylnitrile was added for 22 minutes. The foamed polyurethane sheet swollen with methyl methacrylate was sandwiched between glass plates and heated at 65 ° C. for 24 hours, and then heated at 100 ° C. for 3 hours. After heating, it was removed from the glass plate and vacuum dried at 50 ° C. The obtained hard foam sheet was ground on both sides to produce a polishing pad having a thickness of 1.2 mm. The obtained polishing pad had a micro rubber A hardness of 95 degrees and a density of 0.8.
2. Closed cell average diameter: 36 μm, number of bubbles: 438 / m
m ² , D hardness: 50 degrees, and the content of polymethyl methacrylate in the polishing pad was 50% by weight. The obtained polishing pad had an equilibrium water absorption of 7.9%. A cushion layer “Suba400” was bonded to the polishing pad to produce a composite polishing pad. Attach the test wafer for global level difference evaluation to the polishing head of the polishing machine.
The composite polishing pad was fixed to a platen of a polishing machine by rotating the polishing pad at 5 rpm, and was rotated in the same direction as the polishing head at 45 rpm.
Minute (polishing pad 1cm ² area per 0.031cc /
) And polishing was performed at a polishing pressure of 0.04 MPa. 20 μm test wafer for global level difference evaluation
The global step between the width wiring region and the 230 μm width wiring region became 0.2 μm, and the polishing time was 4 minutes. Further, the test wafer for dust and scratch evaluation was attached to the polishing head of the polishing machine and rotated at 45 rpm, and the composite polishing pad was fixed to the platen of the polishing machine, and rotated at 45 rpm in the same direction as the rotation direction of the polishing head. 35 cc / min.
Polishing was performed at a polishing pressure of 0.04 MPa while supplying at a rate of 0.031 cc / min per cm ² area). The number of dust on the wafer was one, and no scratch was observed. Also, a test wafer for dishing evaluation of tungsten wiring was attached to a polishing head of a polishing machine at 45 rpm.
And the composite polishing pad is fixed to a platen of a polishing machine, and rotated at 45 rpm in the same direction as the rotation direction of the polishing head.
5 cc / min (0.031 per 1 cm ² area of polishing pad)
(cc / min) and polishing was performed at a polishing pressure of 0.04 MPa. The dishing depth at the center of the tungsten wiring (100 μm width) when the surface of the oxide film is exposed is 0.1 mm.
03 μm.

Example 7 30 parts by weight of polypropylene glycol, 40 parts by weight of diphenylmethane diisocyanate, 0.8 parts by weight of water, 0.3 parts by weight of triethylamine, 1.7 parts by weight of a silicone foam stabilizer, and 0.09 parts by weight of tin octylate Are mixed in a RIM molding machine, and are discharged into a mold to perform pressure molding, and a thickness of 2.2 is obtained.
mm polyurethane foam sheet (micro rubber A hardness =
50 degrees, density: 0.77, closed cell average diameter: 35 μm,
(The number of bubbles: 606 / mm ² , equilibrium water absorption: 21%). The foamed polyurethane sheet was immersed in methyl methacrylate containing 0.1 part by weight of azobisisobutylnitrile for 28 minutes. The foamed polyurethane sheet swollen with methyl methacrylate was sandwiched between glass plates and heated at 65 ° C. for 24 hours, and then heated at 100 ° C. for 3 hours. After heating, it was removed from the glass plate and vacuum dried at 50 ° C. The obtained hard foam sheet was ground on both sides to produce a polishing pad having a thickness of 1.2 mm. The obtained polishing pad has a micro rubber A hardness of 97 degrees and a density of 0.8.
1. Closed cell average diameter: 35 μm, number of bubbles: 469 / m
m ² , D hardness: 56 degrees, and the content of polymethyl methacrylate in the polishing pad was 55% by weight. The obtained polishing pad had an equilibrium water absorption of 7.9%. A cushion layer “Suba400” was bonded to the polishing pad to produce a composite polishing pad. Attach the test wafer for global level difference evaluation to the polishing head of the polishing machine.
The composite polishing pad was fixed to a platen of a polishing machine by rotating the polishing pad at 5 rpm, and was rotated in the same direction as the polishing head at 45 rpm.
Minute (polishing pad 1cm ² area per 0.031cc /
) And polishing was performed at a polishing pressure of 0.04 MPa. 20 μm test wafer for global level difference evaluation
The global step between the width wiring region and the 230 μm width wiring region became 0.2 μm, and the polishing time was 4 minutes. Further, the test wafer for dust and scratch evaluation was attached to the polishing head of the polishing machine and rotated at 45 rpm, and the composite polishing pad was fixed to the platen of the polishing machine, and rotated at 45 rpm in the same direction as the rotation direction of the polishing head. 35 cc / min.
Polishing was performed at a polishing pressure of 0.04 MPa while supplying at a rate of 0.031 cc / min per cm ² area). The number of dust on the wafer was one, and no scratch was observed. Also, a test wafer for dishing evaluation of tungsten wiring was attached to a polishing head of a polishing machine at 45 rpm.
And the composite polishing pad is fixed to a platen of a polishing machine, and rotated at 45 rpm in the same direction as the rotation direction of the polishing head.
5 cc / min (0.031 per 1 cm ² area of polishing pad)
(cc / min) and polishing was performed at a polishing pressure of 0.04 MPa. The dishing depth at the center of the tungsten wiring (100 μm width) when the surface of the oxide film is exposed is 0.1 mm.
03 μm.

Example 8 30 parts by weight of polypropylene glycol, 40 parts by weight of diphenylmethane diisocyanate, 0.5 part by weight of water, 0.3 part by weight of triethylamine, 1.7 parts by weight of a silicone foam stabilizer, and 0.09 parts by weight of tin octylate Are mixed by a RIM molding machine, and are discharged into a mold to perform pressure molding to form a thickness of 2.2.
mm polyurethane foam sheet (micro rubber A hardness =
55 °, density: 0.87, closed cell average diameter: 28 μm,
(The number of bubbles: 674 cells / mm ² , equilibrium water absorption: 22%). The foamed polyurethane sheet was immersed in methyl methacrylate to which 0.1 part by weight of azobisisobutylnitrile was added for 20 minutes. The foamed polyurethane sheet swollen with methyl methacrylate was sandwiched between glass plates and heated at 65 ° C. for 24 hours, and then heated at 100 ° C. for 3 hours. After heating, it was removed from the glass plate and vacuum dried at 50 ° C. The obtained hard foam sheet was ground on both sides to produce a polishing pad having a thickness of 1.2 mm. The obtained polishing pad has a micro rubber A hardness of 96 degrees and a density of 0.8.
7, average diameter of closed cells: 38 μm, number of bubbles: 323 / m
m ² , D hardness: 53 degrees, and the content of polymethyl methacrylate in the polishing pad was 50% by weight. The resulting polishing pad had an equilibrium water absorption of 8.3%. A cushion layer “Suba400” was bonded to the polishing pad to produce a composite polishing pad. Attach the test wafer for global level difference evaluation to the polishing head of the polishing machine.
The composite polishing pad was fixed to a platen of a polishing machine by rotating the polishing pad at 5 rpm, and was rotated in the same direction as the polishing head at 45 rpm.
Minute (polishing pad 1cm ² area per 0.031cc /
) And polishing was performed at a polishing pressure of 0.04 MPa. 20 μm test wafer for global level difference evaluation
The global step between the width wiring region and the 230 μm width wiring region became 0.2 μm, and the polishing time was 4 minutes. Further, the test wafer for dust and scratch evaluation was attached to the polishing head of the polishing machine and rotated at 45 rpm, and the composite polishing pad was fixed to the platen of the polishing machine, and rotated at 45 rpm in the same direction as the rotation direction of the polishing head. 35 cc / min.
Polishing was performed at a polishing pressure of 0.04 MPa while supplying at a rate of 0.031 cc / min per cm ² area). The number of dust on the wafer was one, and no scratch was observed. Also, a test wafer for dishing evaluation of tungsten wiring was attached to a polishing head of a polishing machine at 45 rpm.
And the composite polishing pad is fixed to a platen of a polishing machine, and rotated at 45 rpm in the same direction as the rotation direction of the polishing head.
5 cc / min (0.031 per 1 cm ² area of polishing pad)
(cc / min) and polishing was performed at a polishing pressure of 0.04 MPa. The dishing depth at the center of the tungsten wiring (100 μm width) when the surface of the oxide film is exposed is 0.1 mm.
03 μm.

Example 9 35 parts by weight of polypropylene glycol and diphenyl meta
40 parts by weight of diisocyanate, 0.6 parts by weight of water and
0.3 parts by weight of ethylamine and 1.7 parts by weight of silicone foam stabilizer
Part and 0.09 parts by weight of tin octylate are mixed with a RIM molding machine.
Then, the mixture is discharged into a mold and subjected to pressure molding to form a thickness of 2.2.
mm polyurethane foam sheet (micro rubber A hardness =
58 degrees, density: 0.87, closed cell average diameter: 29 μm,
Number of bubbles: 690 / mm^Two, Equilibrium water absorption: 23%)
Made. The foamed polyurethane sheet is azobisisobuty
Methyl methacrylate to which 0.1 part by weight of nitrile is added
For 8 minutes. Methyl methacrylate swells
Sandwich the foamed polyurethane sheet between the glass plates
Heat at 5 ° C for 24 hours, then at 100 ° C for 3 hours
Was. After heating, remove from glass plate and dry under vacuum at 50 ℃
Was done. Grind the obtained rigid foam sheet on both sides and thickness
Produced a polishing pad having a thickness of 1.2 mm. The obtained polishing pad
The micro rubber A hardness of the pad is 98 degrees, the density is 0.91,
Average diameter of closed cells: 39 μm, number of bubbles: 295 / m
m^Two, D hardness: 60 degrees, polymer in polishing pad
The chill methacrylate content was 56% by weight. Profit
The resulting polishing pad had an equilibrium water absorption of 8.4%. K
And a polishing layer “Suba400” bonded to the polishing pad.
In this way, a composite polishing pad was produced. Global step review
The test wafer is attached to the polishing head of the polishing machine and
5 rpm, the composite polishing pad is
At 45 rpm, the same as the rotation direction of the polishing head
The slurry “SC-1” at 35 cc /
Min (polishing pad 1cm ^Two0.031cc / area
The polishing is performed at a polishing pressure of 0.04 MPa while supplying
gave. 20 μm test wafer for global level difference evaluation
The global step between the wide wiring area and the 230 μm wide wiring area is
The polishing time when the thickness reached 0.2 μm was 4 minutes. Also,
Polishing of test wafer for evaluation of strike and scratch
Attached to the head and rotated at 45 rpm, the composite polishing
The pad is fixed to the platen of the polishing machine and polished at 45 rpm
Rotate the head in the same direction as the head
35 cc / min of the slurry “SC-1” (polishing pad 1
cm^Two0.031cc / min per area)
Polishing was performed at a polishing pressure of 0.04 MPa. On wafer
The number of dust is 1 and no scratch is observed
Was. Also, a test for evaluating dishing of tungsten wiring
Attach the wafer to the polishing head of the polishing machine at 45 rpm
And fix the composite polishing pad to the platen of the polishing machine.
At 45 rpm in the same direction as the rotation direction of the polishing head
Rotate and use Cabot tungsten slurry for 3 times.
5cc / min (polishing pad 1cm^Two0.031 per area
(cc / min) while polishing at a polishing pressure of 0.04 MPa.
Polishing was carried out. Tungsten when the oxide film surface is exposed
The dishing depth at the center of the wiring (100 μm width) is 0.
03 μm.

Example 10 32 parts by weight of polypropylene glycol, 43 parts by weight of diphenylmethane diisocyanate, 0.6 parts by weight of water, 0.3 parts by weight of triethylamine, 1.7 parts by weight of a silicone foam stabilizer, and 0.09 parts by weight of tin octylate Are mixed by a RIM molding machine, and are discharged into a mold to perform pressure molding to form a thickness of 2.2.
mm polyurethane foam sheet (micro rubber A hardness =
41 degrees, density: 0.74, closed cell average diameter: 31 μm,
(The number of bubbles: 700 / mm ² , equilibrium water absorption: 21%). The foamed polyurethane sheet was immersed in methyl methacrylate to which 0.1 parts by weight of azobisisobutylnitrile was added for 25 minutes. The foamed polyurethane sheet swollen with methyl methacrylate was sandwiched between glass plates and heated at 65 ° C. for 24 hours, and then heated at 100 ° C. for 3 hours. After heating, it was removed from the glass plate and vacuum dried at 50 ° C. The obtained hard foam sheet was ground on both sides to produce a polishing pad having a thickness of 1.2 mm. The obtained polishing pad had a micro rubber A hardness of 95 degrees and a density of 0.7.
6. Closed cell average diameter: 37 μm, number of bubbles: 434 / m
m ² , D hardness: 59 degrees, and the content of polymethyl methacrylate in the polishing pad was 64% by weight. The obtained polishing pad had an equilibrium water absorption of 8.2%. A cushion layer “Suba400” was bonded to the polishing pad to produce a composite polishing pad. Attach the test wafer for global level difference evaluation to the polishing head of the polishing machine.
The composite polishing pad was fixed to a platen of a polishing machine by rotating the polishing pad at 5 rpm, and was rotated in the same direction as the polishing head at 45 rpm.
Minute (polishing pad 1cm ² area per 0.031cc /
) And polishing was performed at a polishing pressure of 0.04 MPa. 20 μm test wafer for global level difference evaluation
The global step between the width wiring region and the 230 μm width wiring region became 0.2 μm, and the polishing time was 4 minutes. Further, the test wafer for dust and scratch evaluation was attached to the polishing head of the polishing machine and rotated at 45 rpm, and the composite polishing pad was fixed to the platen of the polishing machine, and rotated at 45 rpm in the same direction as the rotation direction of the polishing head. 35 cc / min.
Polishing was performed at a polishing pressure of 0.04 MPa while supplying at a rate of 0.031 cc / min per cm ² area). The number of dusts on the wafer was 2, and no scratch was observed. Also, a test wafer for dishing evaluation of tungsten wiring was attached to a polishing head of a polishing machine at 45 rpm.
And the composite polishing pad is fixed to a platen of a polishing machine, and rotated at 45 rpm in the same direction as the rotation direction of the polishing head.
5 cc / min (0.031 per 1 cm ² area of polishing pad)
(cc / min) and polishing was performed at a polishing pressure of 0.04 MPa. The dishing depth at the center of the tungsten wiring (100 μm width) when the surface of the oxide film is exposed is 0.1 mm.
03 μm.

Example 11 32 parts by weight of polypropylene glycol, 43 parts by weight of diphenylmethane diisocyanate, 0.6 parts by weight of water, 0.3 parts by weight of triethylamine, 1.7 parts by weight of a silicone foam stabilizer, and 0.09 parts by weight of tin octylate Are mixed by a RIM molding machine, and are discharged into a mold to perform pressure molding to form a thickness of 2.2.
mm polyurethane foam sheet (micro rubber A hardness =
41 degrees, density: 0.74, closed cell average diameter: 31 μm,
(The number of bubbles: 700 / mm ² , equilibrium water absorption: 21%). The foamed polyurethane sheet was immersed in methyl methacrylate to which 0.1 part by weight of azobisisobutylnitrile was added for 20 minutes. The foamed polyurethane sheet swollen with methyl methacrylate was sandwiched between glass plates and heated at 65 ° C. for 24 hours, and then heated at 100 ° C. for 3 hours. After heating, it was removed from the glass plate and vacuum dried at 50 ° C. The obtained hard foam sheet was ground on both sides to produce a polishing pad having a thickness of 1.2 mm. The obtained polishing pad had a micro rubber A hardness of 94 degrees and a density of 0.7.
6, average diameter of closed cells: 35 μm, number of bubbles: 468 / m
m ² , D hardness: 54 degrees, and the content of polymethyl methacrylate in the polishing pad was 56% by weight. The resulting polishing pad had an equilibrium water absorption of 8.3%. A cushion layer “Suba400” was bonded to the polishing pad to produce a composite polishing pad. Attach the test wafer for global level difference evaluation to the polishing head of the polishing machine.
The composite polishing pad was fixed to a platen of a polishing machine by rotating the polishing pad at 5 rpm, and was rotated in the same direction as the polishing head at 45 rpm.
Minute (polishing pad 1cm ² area per 0.031cc /
) And polishing was performed at a polishing pressure of 0.04 MPa. 20 μm test wafer for global level difference evaluation
The global step between the width wiring region and the 230 μm width wiring region became 0.2 μm, and the polishing time was 4 minutes. Further, the test wafer for dust and scratch evaluation was attached to the polishing head of the polishing machine and rotated at 45 rpm, and the composite polishing pad was fixed to the platen of the polishing machine, and rotated at 45 rpm in the same direction as the rotation direction of the polishing head. 35 cc / min.
Polishing was performed at a polishing pressure of 0.04 MPa while supplying at a rate of 0.031 cc / min per cm ² area). The number of dusts on the wafer was 4, and no scratch was observed. Also, a test wafer for dishing evaluation of tungsten wiring was attached to a polishing head of a polishing machine at 45 rpm.
And the composite polishing pad is fixed to a platen of a polishing machine, and rotated at 45 rpm in the same direction as the rotation direction of the polishing head.
5 cc / min (0.031 per 1 cm ² area of polishing pad)
(cc / min) and polishing was performed at a polishing pressure of 0.04 MPa. The dishing depth at the center of the tungsten wiring (100 μm width) when the surface of the oxide film is exposed is 0.1 mm.
03 μm.

Example 12 32 parts by weight of polypropylene glycol, 43 parts by weight of diphenylmethane diisocyanate, 0.6 parts by weight of water, 0.3 parts by weight of triethylamine, 1.7 parts by weight of a silicone foam stabilizer, and 0.09 parts by weight of tin octylate Is mixed with a RIM molding machine, and is discharged into a mold to perform pressure molding to form a thickness of 2.2.
mm polyurethane foam sheet (micro rubber A hardness =
41 degrees, density: 0.74, closed cell average diameter: 31 μm,
(The number of bubbles: 700 / mm ² , equilibrium water absorption: 21%). The foamed polyurethane sheet was immersed in methyl methacrylate to which 0.1 parts by weight of azobisisobutylnitrile was added for 18 minutes. The foamed polyurethane sheet swollen with methyl methacrylate was sandwiched between glass plates and heated at 65 ° C. for 24 hours, and then heated at 100 ° C. for 3 hours. After heating, it was removed from the glass plate and vacuum dried at 50 ° C. The obtained hard foam sheet was ground on both sides to produce a polishing pad having a thickness of 1.2 mm. The obtained polishing pad had a micro rubber A hardness of 93 degrees and a density of 0.7.
6. Closed cell average diameter: 34 μm, number of bubbles: 483 / m
m ² , D hardness: 50 degrees, and the content of polymethyl methacrylate in the polishing pad was 50% by weight. The obtained polishing pad had an equilibrium water absorption of 8.5%. A cushion layer “Suba400” was bonded to the polishing pad to produce a composite polishing pad. Attach the test wafer for global level difference evaluation to the polishing head of the polishing machine.
The composite polishing pad was fixed to a platen of a polishing machine by rotating the polishing pad at 5 rpm, and was rotated in the same direction as the polishing head at 45 rpm.
Minute (polishing pad 1cm ² area per 0.031cc /
) And polishing was performed at a polishing pressure of 0.04 MPa. 20 μm test wafer for global level difference evaluation
The global step between the width wiring region and the 230 μm width wiring region became 0.2 μm, and the polishing time was 4 minutes. Further, the test wafer for dust and scratch evaluation was attached to the polishing head of the polishing machine and rotated at 45 rpm, and the composite polishing pad was fixed to the platen of the polishing machine, and rotated at 45 rpm in the same direction as the rotation direction of the polishing head. 35 cc / min.
Polishing was performed at a polishing pressure of 0.04 MPa while supplying at a rate of 0.031 cc / min per cm ² area). The number of dusts on the wafer was 3, and no scratch was observed. Also, a test wafer for dishing evaluation of tungsten wiring was attached to a polishing head of a polishing machine at 45 rpm.
And the composite polishing pad is fixed to a platen of a polishing machine, and rotated at 45 rpm in the same direction as the rotation direction of the polishing head.
5 cc / min (0.031 per 1 cm ² area of polishing pad)
(cc / min) and polishing was performed at a polishing pressure of 0.04 MPa. The dishing depth at the center of the tungsten wiring (100 μm width) when the surface of the oxide film is exposed is 0.1 mm.
03 μm.

Example 13 32 parts by weight of polypropylene glycol, 43 parts by weight of diphenylmethane diisocyanate, 0.6 parts by weight of water, 0.3 parts by weight of triethylamine, 1.7 parts by weight of a silicone foam stabilizer, and 0.09 parts by weight of tin octylate Are mixed in a RIM molding machine, and are discharged into a mold to perform pressure molding, and a thickness of 2.2 is obtained.
mm polyurethane foam sheet (micro rubber A hardness =
43 degrees, density: 0.75, closed cell average diameter: 29 μm,
(The number of bubbles: 737 / mm ² , equilibrium water absorption: 22%). The foamed polyurethane sheet was immersed in methyl methacrylate to which 0.1 parts by weight of azobisisobutylnitrile was added for 25 minutes. The foamed polyurethane sheet swollen with methyl methacrylate was sandwiched between glass plates and heated at 65 ° C. for 24 hours, and then heated at 100 ° C. for 3 hours. After heating, it was removed from the glass plate and vacuum dried at 50 ° C. The obtained hard foam sheet was ground on both sides to produce a polishing pad having a thickness of 1.2 mm. The obtained polishing pad had a micro rubber A hardness of 93 degrees and a density of 0.7.
6. Closed cell average diameter: 37 μm, number of bubbles: 410 / m
m ² , D hardness: 59 degrees, and the content of polymethyl methacrylate in the polishing pad was 64% by weight. The resulting polishing pad had an equilibrium water absorption of 8.0%. A cushion layer “Suba400” was bonded to the polishing pad to produce a composite polishing pad. Attach the test wafer for global level difference evaluation to the polishing head of the polishing machine.
The composite polishing pad was fixed to a platen of a polishing machine by rotating the polishing pad at 5 rpm, and was rotated in the same direction as the polishing head at 45 rpm.
Minute (polishing pad 1cm ² area per 0.031cc /
) And polishing was performed at a polishing pressure of 0.04 MPa. 20 μm test wafer for global level difference evaluation
The global step between the width wiring region and the 230 μm width wiring region became 0.2 μm, and the polishing time was 4 minutes. Further, the test wafer for dust and scratch evaluation was attached to the polishing head of the polishing machine and rotated at 45 rpm, and the composite polishing pad was fixed to the platen of the polishing machine, and rotated at 45 rpm in the same direction as the rotation direction of the polishing head. 35 cc / min.
Polishing was performed at a polishing pressure of 0.04 MPa while supplying at a rate of 0.031 cc / min per cm ² area). The number of dusts on the wafer was 2, and no scratch was observed. Also, a test wafer for dishing evaluation of tungsten wiring was attached to a polishing head of a polishing machine at 45 rpm.
And the composite polishing pad is fixed to a platen of a polishing machine, and rotated at 45 rpm in the same direction as the rotation direction of the polishing head.
5 cc / min (0.031 per 1 cm ² area of polishing pad)
(cc / min) and polishing was performed at a polishing pressure of 0.04 MPa. The dishing depth at the center of the tungsten wiring (100 μm width) when the surface of the oxide film is exposed is 0.1 mm.
03 μm.

Example 14 32 parts by weight of polypropylene glycol, 43 parts by weight of diphenylmethane diisocyanate, 0.6 parts by weight of water, 0.3 parts by weight of triethylamine, 1.7 parts by weight of a silicone foam stabilizer, and 0.09 parts by weight of tin octylate Are mixed in a RIM molding machine, and are discharged into a mold to perform pressure molding, and a thickness of 2.2 is obtained.
mm polyurethane foam sheet (micro rubber A hardness =
43 degrees, density: 0.75, closed cell average diameter: 29 μm,
(The number of bubbles: 737 / mm ² , equilibrium water absorption: 22%). The foamed polyurethane sheet was immersed in methyl methacrylate to which 0.1 part by weight of azobisisobutylnitrile was added for 20 minutes. The foamed polyurethane sheet swollen with methyl methacrylate was sandwiched between glass plates and heated at 65 ° C. for 24 hours, and then heated at 100 ° C. for 3 hours. After heating, it was removed from the glass plate and vacuum dried at 50 ° C. The obtained hard foam sheet was ground on both sides to produce a polishing pad having a thickness of 1.2 mm. The obtained polishing pad had a micro rubber A hardness of 95 degrees and a density of 0.7.
7. Closed cell average diameter: 38 μm, Number of bubbles: 432 / m
m ² , D hardness: 54 degrees, and the content of polymethyl methacrylate in the polishing pad was 56% by weight. The obtained polishing pad had an equilibrium water absorption of 8.2%. A cushion layer “Suba400” was bonded to the polishing pad to produce a composite polishing pad. Attach the test wafer for global level difference evaluation to the polishing head of the polishing machine.
The composite polishing pad was fixed to a platen of a polishing machine by rotating the polishing pad at 5 rpm, and was rotated in the same direction as the polishing head at 45 rpm.
Minute (polishing pad 1cm ² area per 0.031cc /
) And polishing was performed at a polishing pressure of 0.04 MPa. 20 μm test wafer for global level difference evaluation
The global step between the width wiring region and the 230 μm width wiring region became 0.2 μm, and the polishing time was 4 minutes. Further, the test wafer for dust and scratch evaluation was attached to the polishing head of the polishing machine and rotated at 45 rpm, and the composite polishing pad was fixed to the platen of the polishing machine, and rotated at 45 rpm in the same direction as the rotation direction of the polishing head. 35 cc / min.
Polishing was performed at a polishing pressure of 0.04 MPa while supplying at a rate of 0.031 cc / min per cm ² area). The number of dusts on the wafer was 3, and no scratch was observed. Also, a test wafer for dishing evaluation of tungsten wiring was attached to a polishing head of a polishing machine at 45 rpm.
And the composite polishing pad is fixed to a platen of a polishing machine, and rotated at 45 rpm in the same direction as the rotation direction of the polishing head.
5 cc / min (0.031 per 1 cm ² area of polishing pad)
(cc / min) and polishing was performed at a polishing pressure of 0.04 MPa. The dishing depth at the center of the tungsten wiring (100 μm width) when the surface of the oxide film is exposed is 0.1 mm.
03 μm.

Example 15 32 parts by weight of polypropylene glycol, 43 parts by weight of diphenylmethane diisocyanate, 0.6 parts by weight of water, 0.3 parts by weight of triethylamine, 1.7 parts by weight of a silicone foam stabilizer, and 0.09 parts by weight of tin octylate Are mixed in a RIM molding machine, and are discharged into a mold to perform pressure molding, and a thickness of 2.2 is obtained.
mm polyurethane foam sheet (micro rubber A hardness =
43 degrees, density: 0.75, closed cell average diameter: 29 μm,
(The number of bubbles: 737 / mm ² , equilibrium water absorption: 22%). The foamed polyurethane sheet was immersed in methyl methacrylate to which 0.1 parts by weight of azobisisobutylnitrile was added for 18 minutes. The foamed polyurethane sheet swollen with methyl methacrylate was sandwiched between glass plates and heated at 65 ° C. for 24 hours, and then heated at 100 ° C. for 3 hours. After heating, it was removed from the glass plate and vacuum dried at 50 ° C. The obtained hard foam sheet was ground on both sides to produce a polishing pad having a thickness of 1.2 mm. The obtained polishing pad had a micro rubber A hardness of 95 degrees and a density of 0.7.
7. Closed cell average diameter: 34 μm, number of bubbles: 481 / m
m ² , D hardness: 50 degrees, and the content of polymethyl methacrylate in the polishing pad was 50% by weight. The obtained polishing pad had an equilibrium water absorption of 8.2%. A cushion layer “Suba400” was bonded to the polishing pad to produce a composite polishing pad. Attach the test wafer for global level difference evaluation to the polishing head of the polishing machine.
The composite polishing pad was fixed to a platen of a polishing machine by rotating the polishing pad at 5 rpm, and was rotated in the same direction as the polishing head at 45 rpm.
Minute (polishing pad 1cm ² area per 0.031cc /
) And polishing was performed at a polishing pressure of 0.04 MPa. 20 μm test wafer for global level difference evaluation
The global step between the width wiring region and the 230 μm width wiring region became 0.2 μm, and the polishing time was 4 minutes. Further, the test wafer for dust and scratch evaluation was attached to the polishing head of the polishing machine and rotated at 45 rpm, and the composite polishing pad was fixed to the platen of the polishing machine, and rotated at 45 rpm in the same direction as the rotation direction of the polishing head. 35 cc / min.
Polishing was performed at a polishing pressure of 0.04 MPa while supplying at a rate of 0.031 cc / min per cm ² area). The number of dust on the wafer was one, and no scratch was observed. Also, a test wafer for dishing evaluation of tungsten wiring was attached to a polishing head of a polishing machine at 45 rpm.
And the composite polishing pad is fixed to a platen of a polishing machine, and rotated at 45 rpm in the same direction as the rotation direction of the polishing head.
5 cc / min (0.031 per 1 cm ² area of polishing pad)
(cc / min) and polishing was performed at a polishing pressure of 0.04 MPa. The dishing depth at the center of the tungsten wiring (100 μm width) when the surface of the oxide film is exposed is 0.1 mm.
03 μm.

Example 16 33 parts by weight of polypropylene glycol, 44 parts by weight of diphenylmethane diisocyanate, 0.7 parts by weight of water, 0.3 parts by weight of triethylamine, 1.7 parts by weight of a silicone foam stabilizer, and 0.09 parts by weight of tin octylate Are mixed in a RIM molding machine, and are discharged into a mold to perform pressure molding, and a thickness of 2.2 is obtained.
mm polyurethane foam sheet (micro rubber A hardness =
42 degrees, density: 0.69, closed cell average diameter: 31 μm,
(The number of bubbles: 774 / mm ² , equilibrium water absorption: 23%). The foamed polyurethane sheet was immersed in methyl methacrylate to which 0.1 parts by weight of azobisisobutylnitrile was added for 25 minutes. The foamed polyurethane sheet swollen with methyl methacrylate was sandwiched between glass plates and heated at 65 ° C. for 24 hours, and then heated at 100 ° C. for 3 hours. After heating, it was removed from the glass plate and vacuum dried at 50 ° C. The obtained hard foam sheet was ground on both sides to produce a polishing pad having a thickness of 1.2 mm. The obtained polishing pad had a micro rubber A hardness of 97 degrees and a density of 0.7.
2, average diameter of closed cells: 38 μm, number of bubbles: 420 / m
m ² , D hardness: 59 degrees, and the content of polymethyl methacrylate in the polishing pad was 64% by weight. The obtained polishing pad had an equilibrium water absorption of 7.8%. A cushion layer “Suba400” was bonded to the polishing pad to produce a composite polishing pad. Attach the test wafer for global level difference evaluation to the polishing head of the polishing machine.
The composite polishing pad was fixed to a platen of a polishing machine by rotating the polishing pad at 5 rpm, and was rotated in the same direction as the polishing head at 45 rpm.
Minute (polishing pad 1cm ² area per 0.031cc /
) And polishing was performed at a polishing pressure of 0.04 MPa. 20 μm test wafer for global level difference evaluation
The global step between the width wiring region and the 230 μm width wiring region became 0.2 μm, and the polishing time was 4 minutes. Further, the test wafer for dust and scratch evaluation was attached to the polishing head of the polishing machine and rotated at 45 rpm, and the composite polishing pad was fixed to the platen of the polishing machine, and rotated at 45 rpm in the same direction as the rotation direction of the polishing head. 35 cc / min.
Polishing was performed at a polishing pressure of 0.04 MPa while supplying at a rate of 0.031 cc / min per cm ² area). The number of dusts on the wafer was 2, and no scratch was observed. Also, a test wafer for dishing evaluation of tungsten wiring was attached to a polishing head of a polishing machine at 45 rpm.
And the composite polishing pad is fixed to a platen of a polishing machine, and rotated at 45 rpm in the same direction as the rotation direction of the polishing head.
5 cc / min (0.031 per 1 cm ² area of polishing pad)
(cc / min) and polishing was performed at a polishing pressure of 0.04 MPa. The dishing depth at the center of the tungsten wiring (100 μm width) when the surface of the oxide film is exposed is 0.1 mm.
03 μm.

Example 17 33 parts by weight of polypropylene glycol, 44 parts by weight of diphenylmethane diisocyanate, 0.7 parts by weight of water, 0.3 parts by weight of triethylamine, 1.7 parts by weight of a silicone foam stabilizer, and 0.09 parts by weight of tin octylate Are mixed in a RIM molding machine, and are discharged into a mold to perform pressure molding, and a thickness of 2.2 is obtained.
mm polyurethane foam sheet (micro rubber A hardness =
42 degrees, density: 0.69, closed cell average diameter: 31 μm,
(The number of bubbles: 774 / mm ² , equilibrium water absorption: 23%). The foamed polyurethane sheet was immersed in methyl methacrylate to which 0.1 part by weight of azobisisobutylnitrile was added for 20 minutes. The foamed polyurethane sheet swollen with methyl methacrylate was sandwiched between glass plates and heated at 65 ° C. for 24 hours, and then heated at 100 ° C. for 3 hours. After heating, it was removed from the glass plate and vacuum dried at 50 ° C. The obtained hard foam sheet was ground on both sides to produce a polishing pad having a thickness of 1.2 mm. The resulting polishing pad has a micro rubber A hardness of 96 degrees and a density of 0.7.
1. Closed cell average diameter: 35 μm, number of bubbles: 445 / m
m ² , D hardness: 54 degrees, and the content of polymethyl methacrylate in the polishing pad was 55% by weight. The obtained polishing pad had an equilibrium water absorption of 7.8%. A cushion layer “Suba400” was bonded to the polishing pad to produce a composite polishing pad. Attach the test wafer for global level difference evaluation to the polishing head of the polishing machine.
The composite polishing pad was fixed to a platen of a polishing machine by rotating the polishing pad at 5 rpm, and was rotated in the same direction as the polishing head at 45 rpm.
Minute (polishing pad 1cm ² area per 0.031cc /
) And polishing was performed at a polishing pressure of 0.04 MPa. 20 μm test wafer for global level difference evaluation
The global step between the width wiring region and the 230 μm width wiring region became 0.2 μm, and the polishing time was 4 minutes. Further, the test wafer for dust and scratch evaluation was attached to the polishing head of the polishing machine and rotated at 45 rpm, and the composite polishing pad was fixed to the platen of the polishing machine, and rotated at 45 rpm in the same direction as the rotation direction of the polishing head. 35 cc / min.
Polishing was performed at a polishing pressure of 0.04 MPa while supplying at a rate of 0.031 cc / min per cm ² area). The number of dust on the wafer was one, and no scratch was observed. Also, a test wafer for dishing evaluation of tungsten wiring was attached to a polishing head of a polishing machine at 45 rpm.
And the composite polishing pad is fixed to a platen of a polishing machine, and rotated at 45 rpm in the same direction as the rotation direction of the polishing head.
5 cc / min (0.031 per 1 cm ² area of polishing pad)
(cc / min) and polishing was performed at a polishing pressure of 0.04 MPa. The dishing depth at the center of the tungsten wiring (100 μm width) when the surface of the oxide film is exposed is 0.1 mm.
03 μm.

Example 18 33 parts by weight of polypropylene glycol, 44 parts by weight of diphenylmethane diisocyanate, 0.7 parts by weight of water, 0.3 parts by weight of triethylamine, 1.7 parts by weight of a silicone foam stabilizer, and 0.09 parts by weight of tin octylate Are mixed in a RIM molding machine, and are discharged into a mold to perform pressure molding, and a thickness of 2.2 is obtained.
mm polyurethane foam sheet (micro rubber A hardness =
42 degrees, density: 0.69, closed cell average diameter: 31 μm,
(The number of bubbles: 774 / mm ² , equilibrium water absorption: 23%). The foamed polyurethane sheet was immersed in methyl methacrylate to which 0.1 parts by weight of azobisisobutylnitrile was added for 18 minutes. The foamed polyurethane sheet swollen with methyl methacrylate was sandwiched between glass plates and heated at 65 ° C. for 24 hours, and then heated at 100 ° C. for 3 hours. After heating, it was removed from the glass plate and vacuum dried at 50 ° C. The obtained hard foam sheet was ground on both sides to produce a polishing pad having a thickness of 1.2 mm. The obtained polishing pad had a micro rubber A hardness of 97 degrees and a density of 0.7.
2, average diameter of closed cells: 34 μm, number of bubbles: 483 / m
m ² , D hardness: 49 degrees, and the content of polymethyl methacrylate in the polishing pad was 50% by weight. The resulting polishing pad had an equilibrium water absorption of 8.4%. A cushion layer “Suba400” was bonded to the polishing pad to produce a composite polishing pad. Attach the test wafer for global level difference evaluation to the polishing head of the polishing machine.
The composite polishing pad was fixed to a platen of a polishing machine by rotating the polishing pad at 5 rpm, and was rotated in the same direction as the polishing head at 45 rpm.
Minute (polishing pad 1cm ² area per 0.031cc /
) And polishing was performed at a polishing pressure of 0.04 MPa. 20 μm test wafer for global level difference evaluation
The global step between the width wiring region and the 230 μm width wiring region became 0.2 μm, and the polishing time was 4 minutes. Further, the test wafer for dust and scratch evaluation was attached to the polishing head of the polishing machine and rotated at 45 rpm, and the composite polishing pad was fixed to the platen of the polishing machine, and rotated at 45 rpm in the same direction as the rotation direction of the polishing head. 35 cc / min.
Polishing was performed at a polishing pressure of 0.04 MPa while supplying at a rate of 0.031 cc / min per cm ² area). The number of dusts on the wafer was 3, and no scratch was observed. Also, a test wafer for dishing evaluation of tungsten wiring was attached to a polishing head of a polishing machine at 45 rpm.
And the composite polishing pad is fixed to a platen of a polishing machine, and rotated at 45 rpm in the same direction as the rotation direction of the polishing head.
5 cc / min (0.031 per 1 cm ² area of polishing pad)
(cc / min) and polishing was performed at a polishing pressure of 0.04 MPa. The dishing depth at the center of the tungsten wiring (100 μm width) when the surface of the oxide film is exposed is 0.1 mm.
03 μm.

Example 19 33 parts by weight of polypropylene glycol, 44 parts by weight of diphenylmethane diisocyanate, 0.7 parts by weight of water, 0.3 parts by weight of triethylamine, 1.7 parts by weight of a silicone foam stabilizer and 0.09 parts by weight of tin octylate Are mixed by a RIM molding machine, and are discharged into a mold to perform pressure molding to form a thickness of 2.2.
mm polyurethane foam sheet (micro rubber A hardness =
50 degrees, density: 0.87, closed cell average diameter: 26 μm,
(The number of air bubbles: 687 / mm ² , equilibrium water absorption: 23%). The foamed polyurethane sheet was immersed in methyl methacrylate to which 0.1 parts by weight of azobisisobutylnitrile was added for 25 minutes. The foamed polyurethane sheet swollen with methyl methacrylate was sandwiched between glass plates and heated at 65 ° C. for 24 hours, and then heated at 100 ° C. for 3 hours. After heating, it was removed from the glass plate and vacuum dried at 50 ° C. The obtained hard foam sheet was ground on both sides to produce a polishing pad having a thickness of 1.2 mm. The obtained polishing pad has a micro rubber A hardness of 97 degrees and a density of 0.8.
8. Closed cell average diameter: 37 μm, number of bubbles: 412 / m
m ² , D hardness: 60 degrees, and the content of polymethyl methacrylate in the polishing pad was 64% by weight. The obtained polishing pad had an equilibrium water absorption of 7.8%. A cushion layer “Suba400” was bonded to the polishing pad to produce a composite polishing pad. Attach the test wafer for global level difference evaluation to the polishing head of the polishing machine.
The composite polishing pad was fixed to a platen of a polishing machine by rotating the polishing pad at 5 rpm, and was rotated in the same direction as the polishing head at 45 rpm.
Minute (polishing pad 1cm ² area per 0.031cc /
) And polishing was performed at a polishing pressure of 0.04 MPa. 20 μm test wafer for global level difference evaluation
The global step between the width wiring region and the 230 μm width wiring region became 0.2 μm, and the polishing time was 4 minutes. Further, the test wafer for dust and scratch evaluation was attached to the polishing head of the polishing machine and rotated at 45 rpm, and the composite polishing pad was fixed to the platen of the polishing machine, and rotated at 45 rpm in the same direction as the rotation direction of the polishing head. 35 cc / min.
Polishing was performed at a polishing pressure of 0.04 MPa while supplying at a rate of 0.031 cc / min per cm ² area). The number of dust on the wafer was one, and no scratch was observed. Also, a test wafer for dishing evaluation of tungsten wiring was attached to a polishing head of a polishing machine at 45 rpm.
And the composite polishing pad is fixed to a platen of a polishing machine, and rotated at 45 rpm in the same direction as the rotation direction of the polishing head.
5 cc / min (0.031 per 1 cm ² area of polishing pad)
(cc / min) and polishing was performed at a polishing pressure of 0.04 MPa. The dishing depth at the center of the tungsten wiring (100 μm width) when the surface of the oxide film is exposed is 0.1 mm.
03 μm.

Example 20 33 parts by weight of polypropylene glycol, 44 parts by weight of diphenylmethane diisocyanate, 0.7 parts by weight of water, 0.3 parts by weight of triethylamine, 1.7 parts by weight of a silicone foam stabilizer, and 0.09 parts by weight of tin octylate Are mixed by a RIM molding machine, and are discharged into a mold to perform pressure molding to form a thickness of 2.2.
mm polyurethane foam sheet (micro rubber A hardness =
50 degrees, density: 0.87, closed cell average diameter: 26 μm,
(The number of air bubbles: 687 / mm ² , equilibrium water absorption: 23%). The foamed polyurethane sheet was immersed in methyl methacrylate to which 0.1 part by weight of azobisisobutylnitrile was added for 20 minutes. The foamed polyurethane sheet swollen with methyl methacrylate was sandwiched between glass plates and heated at 65 ° C. for 24 hours, and then heated at 100 ° C. for 3 hours. After heating, it was removed from the glass plate and vacuum dried at 50 ° C. The obtained hard foam sheet was ground on both sides to produce a polishing pad having a thickness of 1.2 mm. The obtained polishing pad has a micro rubber A hardness of 96 degrees and a density of 0.8.
9, average diameter of closed cells: 36 μm, number of bubbles: 443 / m
m ² , D hardness: 54 degrees, and the content of polymethyl methacrylate in the polishing pad was 55% by weight. The resulting polishing pad had an equilibrium water absorption of 8.1%. A cushion layer “Suba400” was bonded to the polishing pad to produce a composite polishing pad. Attach the test wafer for global level difference evaluation to the polishing head of the polishing machine.
The composite polishing pad was fixed to a platen of a polishing machine by rotating the polishing pad at 5 rpm, and was rotated in the same direction as the polishing head at 45 rpm.
Minute (polishing pad 1cm ² area per 0.031cc /
) And polishing was performed at a polishing pressure of 0.04 MPa. 20 μm test wafer for global level difference evaluation
The global step between the width wiring region and the 230 μm width wiring region became 0.2 μm, and the polishing time was 4 minutes. Further, the test wafer for dust and scratch evaluation was attached to the polishing head of the polishing machine and rotated at 45 rpm, and the composite polishing pad was fixed to the platen of the polishing machine, and rotated at 45 rpm in the same direction as the rotation direction of the polishing head. 35 cc / min.
Polishing was performed at a polishing pressure of 0.04 MPa while supplying at a rate of 0.031 cc / min per cm ² area). The number of dusts on the wafer was 3, and no scratch was observed. Also, a test wafer for dishing evaluation of tungsten wiring was attached to a polishing head of a polishing machine at 45 rpm.
And the composite polishing pad is fixed to a platen of a polishing machine, and rotated at 45 rpm in the same direction as the rotation direction of the polishing head.
5 cc / min (0.031 per 1 cm ² area of polishing pad)
(cc / min) and polishing was performed at a polishing pressure of 0.04 MPa. The dishing depth at the center of the tungsten wiring (100 μm width) when the surface of the oxide film is exposed is 0.1 mm.
03 μm.

Example 21 33 parts by weight of polypropylene glycol, 44 parts by weight of diphenylmethane diisocyanate, 0.7 parts by weight of water, 0.3 parts by weight of triethylamine, 1.7 parts by weight of a silicone foam stabilizer, and 0.09 parts by weight of tin octylate Are mixed in a RIM molding machine, and are discharged into a mold to perform pressure molding, and a thickness of 2.2 is obtained.
mm polyurethane foam sheet (micro rubber A hardness =
50 degrees, density: 0.87, closed cell average diameter: 26 μm,
(The number of air bubbles: 687 / mm ² , equilibrium water absorption: 23%). The foamed polyurethane sheet was immersed in methyl methacrylate to which 0.1 parts by weight of azobisisobutylnitrile was added for 18 minutes. The foamed polyurethane sheet swollen with methyl methacrylate was sandwiched between glass plates and heated at 65 ° C. for 24 hours, and then heated at 100 ° C. for 3 hours. After heating, it was removed from the glass plate and vacuum dried at 50 ° C. The obtained hard foam sheet was ground on both sides to produce a polishing pad having a thickness of 1.2 mm. The obtained polishing pad had a micro rubber A hardness of 95 degrees and a density of 0.8.
8. Closed cell average diameter: 36 μm, number of bubbles: 483 / m
m ² , D hardness: 49 degrees, and the content of polymethyl methacrylate in the polishing pad was 50% by weight. The resulting polishing pad had an equilibrium water absorption of 8.4%. A cushion layer “Suba400” was bonded to the polishing pad to produce a composite polishing pad. Attach the test wafer for global level difference evaluation to the polishing head of the polishing machine.
The composite polishing pad was fixed to a platen of a polishing machine by rotating the polishing pad at 5 rpm, and was rotated in the same direction as the polishing head at 45 rpm.
Minute (polishing pad 1cm ² area per 0.031cc /
) And polishing was performed at a polishing pressure of 0.04 MPa. 20 μm test wafer for global level difference evaluation
The global step between the width wiring region and the 230 μm width wiring region became 0.2 μm, and the polishing time was 4 minutes. Further, the test wafer for dust and scratch evaluation was attached to the polishing head of the polishing machine and rotated at 45 rpm, and the composite polishing pad was fixed to the platen of the polishing machine, and rotated at 45 rpm in the same direction as the rotation direction of the polishing head. 35 cc / min.
Polishing was performed at a polishing pressure of 0.04 MPa while supplying at a rate of 0.031 cc / min per cm ² area). The number of dusts on the wafer was 4, and no scratch was observed. Also, a test wafer for dishing evaluation of tungsten wiring was attached to a polishing head of a polishing machine at 45 rpm.
And the composite polishing pad is fixed to a platen of a polishing machine, and rotated at 45 rpm in the same direction as the rotation direction of the polishing head.
5 cc / min (0.031 per 1 cm ² area of polishing pad)
(cc / min) and polishing was performed at a polishing pressure of 0.04 MPa. The dishing depth at the center of the tungsten wiring (100 μm width) when the surface of the oxide film is exposed is 0.1 mm.
03 μm.

Example 22 31 parts by weight of polypropylene glycol, 40 parts by weight of diphenylmethane diisocyanate, 0.6 parts by weight of water, 0.3 parts by weight of triethylamine, 1.7 parts by weight of a silicone foam stabilizer, and 0.09 parts by weight of tin octylate Are mixed by a RIM molding machine, and are discharged into a mold to perform pressure molding to form a thickness of 2.2.
mm polyurethane foam sheet (micro rubber A hardness =
43 degrees, density: 0.68, average closed cell diameter: 30 μm,
(The number of bubbles: 886 / mm ² , equilibrium water absorption: 24%). The foamed polyurethane sheet was immersed in methyl methacrylate to which 0.1 parts by weight of azobisisobutylnitrile was added for 25 minutes. The foamed polyurethane sheet swollen with methyl methacrylate was sandwiched between glass plates and heated at 65 ° C. for 24 hours, and then heated at 100 ° C. for 3 hours. After heating, it was removed from the glass plate and vacuum dried at 50 ° C. The obtained hard foam sheet was ground on both sides to produce a polishing pad having a thickness of 1.2 mm. The obtained polishing pad had a micro rubber A hardness of 98 degrees and a density of 0.7.
2. Closed cell average diameter: 37 μm, number of bubbles: 480 / m
m ² , D hardness: 59 degrees, and the content of polymethyl methacrylate in the polishing pad was 64% by weight. The obtained polishing pad had an equilibrium water absorption of 7.8%. A cushion layer “Suba400” was bonded to the polishing pad to produce a composite polishing pad. Attach the test wafer for global level difference evaluation to the polishing head of the polishing machine.
The composite polishing pad was fixed to a platen of a polishing machine by rotating the polishing pad at 5 rpm, and was rotated in the same direction as the polishing head at 45 rpm.
Minute (polishing pad 1cm ² area per 0.031cc /
) And polishing was performed at a polishing pressure of 0.04 MPa. 20 μm test wafer for global level difference evaluation
The global step between the width wiring region and the 230 μm width wiring region became 0.2 μm, and the polishing time was 4 minutes. Further, the test wafer for dust and scratch evaluation was attached to the polishing head of the polishing machine and rotated at 45 rpm, and the composite polishing pad was fixed to the platen of the polishing machine, and rotated at 45 rpm in the same direction as the rotation direction of the polishing head. 35 cc / min.
Polishing was performed at a polishing pressure of 0.04 MPa while supplying at a rate of 0.031 cc / min per cm ² area). The number of dusts on the wafer was 2, and no scratch was observed. Also, a test wafer for dishing evaluation of tungsten wiring was attached to a polishing head of a polishing machine at 45 rpm.
And the composite polishing pad is fixed to a platen of a polishing machine, and rotated at 45 rpm in the same direction as the rotation direction of the polishing head.
5 cc / min (0.031 per 1 cm ² area of polishing pad)
(cc / min) and polishing was performed at a polishing pressure of 0.04 MPa. The dishing depth at the center of the tungsten wiring (100 μm width) when the surface of the oxide film is exposed is 0.1 mm.
03 μm.

Example 23 31 parts by weight of polypropylene glycol, 40 parts by weight of diphenylmethane diisocyanate, 0.6 parts by weight of water, 0.3 parts by weight of triethylamine, 1.7 parts by weight of a silicone foam stabilizer, and 0.09 parts by weight of tin octylate Are mixed by a RIM molding machine, and are discharged into a mold to perform pressure molding to form a thickness of 2.2.
mm polyurethane foam sheet (micro rubber A hardness =
43 degrees, density: 0.68, average closed cell diameter: 30 μm,
(The number of bubbles: 886 / mm ² , equilibrium water absorption: 24%). The foamed polyurethane sheet was immersed in methyl methacrylate to which 0.1 part by weight of azobisisobutylnitrile was added for 20 minutes. The foamed polyurethane sheet swollen with methyl methacrylate was sandwiched between glass plates and heated at 65 ° C. for 24 hours, and then heated at 100 ° C. for 3 hours. After heating, it was removed from the glass plate and vacuum dried at 50 ° C. The obtained hard foam sheet was ground on both sides to produce a polishing pad having a thickness of 1.2 mm. The obtained polishing pad had a micro rubber A hardness of 98 degrees and a density of 0.7.
2. Closed cell average diameter: 37 μm, number of bubbles: 512 / m
m ² , D hardness: 53 degrees, and the content of polymethyl methacrylate in the polishing pad was 55% by weight. The resulting polishing pad had an equilibrium water absorption of 8.1%. A cushion layer “Suba400” was bonded to the polishing pad to produce a composite polishing pad. Attach the test wafer for global level difference evaluation to the polishing head of the polishing machine.
The composite polishing pad was fixed to a platen of a polishing machine by rotating the polishing pad at 5 rpm, and was rotated in the same direction as the polishing head at 45 rpm.
Minute (polishing pad 1cm ² area per 0.031cc /
) And polishing was performed at a polishing pressure of 0.04 MPa. 20 μm test wafer for global level difference evaluation
The global step between the width wiring region and the 230 μm width wiring region became 0.2 μm, and the polishing time was 4 minutes. Further, the test wafer for dust and scratch evaluation was attached to the polishing head of the polishing machine and rotated at 45 rpm, and the composite polishing pad was fixed to the platen of the polishing machine, and rotated at 45 rpm in the same direction as the rotation direction of the polishing head. 35 cc / min.
Polishing was performed at a polishing pressure of 0.04 MPa while supplying at a rate of 0.031 cc / min per cm ² area). The number of dusts on the wafer was 3, and no scratch was observed. Also, a test wafer for dishing evaluation of tungsten wiring was attached to a polishing head of a polishing machine at 45 rpm.
And the composite polishing pad is fixed to a platen of a polishing machine, and rotated at 45 rpm in the same direction as the rotation direction of the polishing head.
5 cc / min (0.031 per 1 cm ² area of polishing pad)
(cc / min) and polishing was performed at a polishing pressure of 0.04 MPa. The dishing depth at the center of the tungsten wiring (100 μm width) when the surface of the oxide film is exposed is 0.1 mm.
03 μm.

Example 24 31 parts by weight of polypropylene glycol, 40 parts by weight of diphenylmethane diisocyanate, 0.6 parts by weight of water, 0.3 parts by weight of triethylamine, 1.7 parts by weight of a silicone foam stabilizer, and 0.09 parts by weight of tin octylate Are mixed in a RIM molding machine, and are discharged into a mold to perform pressure molding, and a thickness of 2.2 is obtained.
mm polyurethane foam sheet (micro rubber A hardness =
43 degrees, density: 0.68, average closed cell diameter: 30 μm,
(The number of bubbles: 886 / mm ² , equilibrium water absorption: 24%). The foamed polyurethane sheet was immersed in methyl methacrylate to which 0.1 parts by weight of azobisisobutylnitrile was added for 18 minutes. The foamed polyurethane sheet swollen with methyl methacrylate was sandwiched between glass plates and heated at 65 ° C. for 24 hours, and then heated at 100 ° C. for 3 hours. After heating, it was removed from the glass plate and vacuum dried at 50 ° C. The obtained hard foam sheet was ground on both sides to produce a polishing pad having a thickness of 1.2 mm. The obtained polishing pad had a micro rubber A hardness of 98 degrees and a density of 0.7.
2. Closed cell average diameter: 37 μm, number of bubbles: 612 / m
m ² , D hardness: 49 degrees, and the content of polymethyl methacrylate in the polishing pad was 50% by weight. The resulting polishing pad had an equilibrium water absorption of 8.1%. A cushion layer “Suba400” was bonded to the polishing pad to produce a composite polishing pad. Attach the test wafer for global level difference evaluation to the polishing head of the polishing machine.
The composite polishing pad was fixed to a platen of a polishing machine by rotating the polishing pad at 5 rpm, and was rotated in the same direction as the polishing head at 45 rpm.
Minute (polishing pad 1cm ² area per 0.031cc /
) And polishing was performed at a polishing pressure of 0.04 MPa. 20 μm test wafer for global level difference evaluation
The global step between the width wiring region and the 230 μm width wiring region became 0.2 μm, and the polishing time was 4 minutes. Further, the test wafer for dust and scratch evaluation was attached to the polishing head of the polishing machine and rotated at 45 rpm, and the composite polishing pad was fixed to the platen of the polishing machine, and rotated at 45 rpm in the same direction as the rotation direction of the polishing head. 35 cc / min.
Polishing was performed at a polishing pressure of 0.04 MPa while supplying at a rate of 0.031 cc / min per cm ² area). The number of dusts on the wafer was 2, and no scratch was observed. Also, a test wafer for dishing evaluation of tungsten wiring was attached to a polishing head of a polishing machine at 45 rpm.
And the composite polishing pad is fixed to a platen of a polishing machine, and rotated at 45 rpm in the same direction as the rotation direction of the polishing head.
5 cc / min (0.031 per 1 cm ² area of polishing pad)
(cc / min) and polishing was performed at a polishing pressure of 0.04 MPa. The dishing depth at the center of the tungsten wiring (100 μm width) when the surface of the oxide film is exposed is 0.1 mm.
03 μm.

Example 25 33 parts by weight of polypropylene glycol, 42 parts by weight of diphenylmethane diisocyanate, 0.4 part by weight of water, 0.3 part by weight of triethylamine, 1.7 parts by weight of a silicone foam stabilizer, and 0.09 parts by weight of tin octylate Are mixed by a RIM molding machine, and are discharged into a mold to perform pressure molding to form a thickness of 2.2.
mm polyurethane foam sheet (micro rubber A hardness =
49 degrees, density: 0.83, closed cell average diameter: 29 μm,
(The number of air bubbles: 656 / mm ² , equilibrium water absorption: 24%). The foamed polyurethane sheet was immersed in methyl methacrylate to which 0.1 parts by weight of azobisisobutylnitrile was added for 25 minutes. The foamed polyurethane sheet swollen with methyl methacrylate was sandwiched between glass plates and heated at 65 ° C. for 24 hours, and then heated at 100 ° C. for 3 hours. After heating, it was removed from the glass plate and vacuum dried at 50 ° C. The obtained hard foam sheet was ground on both sides to produce a polishing pad having a thickness of 1.2 mm. The resulting polishing pad has a micro rubber A hardness of 98 degrees and a density of 0.8.
4. Closed cell average diameter: 38 μm, number of bubbles: 412 / m
m ² , D hardness: 61 degrees, and the content of polymethyl methacrylate in the polishing pad was 64% by weight. The obtained polishing pad had an equilibrium water absorption of 7.7%. A cushion layer “Suba400” was bonded to the polishing pad to produce a composite polishing pad. Attach the test wafer for global level difference evaluation to the polishing head of the polishing machine.
The composite polishing pad was fixed to a platen of a polishing machine by rotating the polishing pad at 5 rpm, and was rotated in the same direction as the polishing head at 45 rpm.
Minute (polishing pad 1cm ² area per 0.031cc /
) And polishing was performed at a polishing pressure of 0.04 MPa. 20 μm test wafer for global level difference evaluation
The global step between the width wiring region and the 230 μm width wiring region became 0.2 μm, and the polishing time was 4 minutes. Further, the test wafer for dust and scratch evaluation was attached to the polishing head of the polishing machine and rotated at 45 rpm, and the composite polishing pad was fixed to the platen of the polishing machine, and rotated at 45 rpm in the same direction as the rotation direction of the polishing head. 35 cc / min.
Polishing was performed at a polishing pressure of 0.04 MPa while supplying at a rate of 0.031 cc / min per cm ² area). The number of dusts on the wafer was 5, and no scratch was observed. Also, a test wafer for dishing evaluation of tungsten wiring was attached to a polishing head of a polishing machine at 45 rpm.
And the composite polishing pad is fixed to a platen of a polishing machine, and rotated at 45 rpm in the same direction as the rotation direction of the polishing head.
5 cc / min (0.031 per 1 cm ² area of polishing pad)
(cc / min) and polishing was performed at a polishing pressure of 0.04 MPa. The dishing depth at the center of the tungsten wiring (100 μm width) when the surface of the oxide film is exposed is 0.1 mm.
03 μm.

Example 26 33 parts by weight of polypropylene glycol, 42 parts by weight of diphenylmethane diisocyanate, 0.4 part by weight of water, 0.3 part by weight of triethylamine, 1.7 parts by weight of a silicone foam stabilizer and 0.09 parts by weight of tin octylate Are mixed in a RIM molding machine, and are discharged into a mold to perform pressure molding, and a thickness of 2.2 is obtained.
mm polyurethane foam sheet (micro rubber A hardness =
49 degrees, density: 0.83, closed cell average diameter: 29 μm,
(The number of air bubbles: 656 / mm ² , equilibrium water absorption: 24%). The foamed polyurethane sheet was immersed in methyl methacrylate to which 0.1 part by weight of azobisisobutylnitrile was added for 20 minutes. The foamed polyurethane sheet swollen with methyl methacrylate was sandwiched between glass plates and heated at 65 ° C. for 24 hours, and then heated at 100 ° C. for 3 hours. After heating, it was removed from the glass plate and vacuum dried at 50 ° C. The obtained hard foam sheet was ground on both sides to produce a polishing pad having a thickness of 1.2 mm. The obtained polishing pad has a micro rubber A hardness of 96 degrees and a density of 0.8.
4. Closed cell average diameter: 35 μm, number of bubbles: 464 / m
m ² , D hardness: 55 degrees, and the content of polymethyl methacrylate in the polishing pad was 55% by weight. The resulting polishing pad had an equilibrium water absorption of 8.1%. A cushion layer “Suba400” was bonded to the polishing pad to produce a composite polishing pad. Attach the test wafer for global level difference evaluation to the polishing head of the polishing machine.
The composite polishing pad was fixed to a platen of a polishing machine by rotating the polishing pad at 5 rpm, and was rotated in the same direction as the polishing head at 45 rpm.
Minute (polishing pad 1cm ² area per 0.031cc /
) And polishing was performed at a polishing pressure of 0.04 MPa. 20 μm test wafer for global level difference evaluation
The global step between the width wiring region and the 230 μm width wiring region became 0.2 μm, and the polishing time was 4 minutes. Further, the test wafer for dust and scratch evaluation was attached to the polishing head of the polishing machine and rotated at 45 rpm, and the composite polishing pad was fixed to the platen of the polishing machine, and rotated at 45 rpm in the same direction as the rotation direction of the polishing head. 35 cc / min.
Polishing was performed at a polishing pressure of 0.04 MPa while supplying at a rate of 0.031 cc / min per cm ² area). The number of dusts on the wafer was 3, and no scratch was observed. Also, a test wafer for dishing evaluation of tungsten wiring was attached to a polishing head of a polishing machine at 45 rpm.
And the composite polishing pad is fixed to a platen of a polishing machine, and rotated at 45 rpm in the same direction as the rotation direction of the polishing head.
5 cc / min (0.031 per 1 cm ² area of polishing pad)
(cc / min) and polishing was performed at a polishing pressure of 0.04 MPa. The dishing depth at the center of the tungsten wiring (100 μm width) when the surface of the oxide film is exposed is 0.1 mm.
03 μm.

Example 27 33 parts by weight of polypropylene glycol, 42 parts by weight of diphenylmethane diisocyanate, 0.4 part by weight of water, 0.3 part by weight of triethylamine, 1.7 parts by weight of a silicone foam stabilizer, and 0.09 parts by weight of tin octylate Are mixed in a RIM molding machine, and are discharged into a mold to perform pressure molding, and a thickness of 2.2 is obtained.
mm polyurethane foam sheet (micro rubber A hardness =
49 degrees, density: 0.83, closed cell average diameter: 29 μm,
(The number of air bubbles: 656 / mm ² , equilibrium water absorption: 24%). The foamed polyurethane sheet was immersed in methyl methacrylate to which 0.1 parts by weight of azobisisobutylnitrile was added for 18 minutes. The foamed polyurethane sheet swollen with methyl methacrylate was sandwiched between glass plates and heated at 65 ° C. for 24 hours, and then heated at 100 ° C. for 3 hours. After heating, it was removed from the glass plate and vacuum dried at 50 ° C. The obtained hard foam sheet was ground on both sides to produce a polishing pad having a thickness of 1.2 mm. The obtained polishing pad had a micro rubber A hardness of 95 degrees and a density of 0.8.
4. Closed cell average diameter: 34 μm, number of bubbles: 485 / m
m ² , D hardness: 50 degrees, and the content of polymethyl methacrylate in the polishing pad was 50% by weight. The resulting polishing pad had an equilibrium water absorption of 8.4%. A cushion layer “Suba400” was bonded to the polishing pad to produce a composite polishing pad. Attach the test wafer for global level difference evaluation to the polishing head of the polishing machine.
The composite polishing pad was fixed to a platen of a polishing machine by rotating the polishing pad at 5 rpm, and was rotated in the same direction as the polishing head at 45 rpm.
Minute (polishing pad 1cm ² area per 0.031cc /
) And polishing was performed at a polishing pressure of 0.04 MPa. 20 μm test wafer for global level difference evaluation
The global step between the width wiring region and the 230 μm width wiring region became 0.2 μm, and the polishing time was 4 minutes. Further, the test wafer for dust and scratch evaluation was attached to the polishing head of the polishing machine and rotated at 45 rpm, and the composite polishing pad was fixed to the platen of the polishing machine, and rotated at 45 rpm in the same direction as the rotation direction of the polishing head. 35 cc / min.
Polishing was performed at a polishing pressure of 0.04 MPa while supplying at a rate of 0.031 cc / min per cm ² area). The number of dusts on the wafer was 2, and no scratch was observed. Also, a test wafer for dishing evaluation of tungsten wiring was attached to a polishing head of a polishing machine at 45 rpm.
And the composite polishing pad is fixed to a platen of a polishing machine, and rotated at 45 rpm in the same direction as the rotation direction of the polishing head.
5 cc / min (0.031 per 1 cm ² area of polishing pad)
(cc / min) and polishing was performed at a polishing pressure of 0.04 MPa. The dishing depth at the center of the tungsten wiring (100 μm width) when the surface of the oxide film is exposed is 0.1 mm.
03 μm.

Example 28 33 parts by weight of polypropylene glycol, 42 parts by weight of diphenylmethane diisocyanate, 0.4 part by weight of water, 0.3 part by weight of triethylamine, 1.7 parts by weight of a silicone foam stabilizer, and 0.09 parts by weight of tin octylate Are mixed by a RIM molding machine, and are discharged into a mold to perform pressure molding to form a thickness of 2.2.
mm polyurethane foam sheet (micro rubber A hardness =
49 degrees, density: 0.72, closed cell average diameter: 22 μm,
(The number of bubbles: 2300 cells / mm 2, equilibrium water absorption: 24%). The foamed polyurethane sheet was immersed in methyl methacrylate to which 0.1 parts by weight of azobisisobutylnitrile was added for 18 minutes. The foamed polyurethane sheet swollen with methyl methacrylate was sandwiched between glass plates and heated at 65 ° C. for 24 hours, and then heated at 100 ° C. for 3 hours. After heating, it was removed from the glass plate and vacuum dried at 50 ° C. The obtained hard foam sheet was ground on both sides to produce a polishing pad having a thickness of 1.2 mm. The obtained polishing pad had a micro rubber A hardness of 95 degrees and a density of 0.7.
5. Closed cell average diameter: 24 μm, number of bubbles: 2200 /
mm2, D hardness: 50 degrees, and the content of polymethyl methacrylate in the polishing pad was 50% by weight.
The obtained polishing pad had an equilibrium water absorption of 5.2%.
A cushion layer “Suba400” was bonded to the polishing pad to produce a composite polishing pad. The test wafer for global level difference evaluation was attached to a polishing head of a polishing machine and rotated at 45 rpm, the composite polishing pad was fixed to a platen of the polishing machine, and rotated at 45 rpm in the same direction as the rotation direction of the polishing head to obtain a slurry “SC- 1 "for 35cc
/ Min (0.031 cc / per 1 cm2 area of polishing pad)
) And polishing was performed at a polishing pressure of 0.04 MPa. 20 μm test wafer for global level difference evaluation
The global step between the width wiring region and the 230 μm width wiring region became 0.2 μm, and the polishing time was 4 minutes. Further, the test wafer for dust and scratch evaluation was attached to the polishing head of the polishing machine and rotated at 45 rpm, and the composite polishing pad was fixed to the platen of the polishing machine, and rotated at 45 rpm in the same direction as the rotation direction of the polishing head. 35 cc / min.
Polishing was performed at a polishing pressure of 0.04 MPa while supplying at a rate of 0.031 cc / min per cm 2 area. The number of dusts on the wafer was 2, and no scratch was observed. Also, a test wafer for dishing evaluation of tungsten wiring was attached to a polishing head of a polishing machine at 45 rpm.
And the composite polishing pad is fixed to a platen of a polishing machine, and rotated at 45 rpm in the same direction as the rotation direction of the polishing head.
5 cc / min (0.031 per 1 cm2 area of polishing pad)
(cc / min) and polishing was performed at a polishing pressure of 0.04 MPa. The dishing depth at the center of the tungsten wiring (100 μm width) when the surface of the oxide film is exposed is 0.1 mm.
03 μm.

Comparative Example 1 30 parts by weight of polypropylene glycol, 40 parts by weight of diphenylmethane diisocyanate, 0.1 part by weight of water, 0.3 part by weight of triethylamine, 0.7 part by weight of a silicone foam stabilizer, and 0.09 part by weight of tin octylate Are mixed in a RIM molding machine, and are discharged into a mold to perform pressure molding, and a thickness of 2.2 is obtained.
mm polyurethane foam sheet (micro rubber A hardness =
49 degrees, density: 0.83, average diameter of closed cells: 170μ
m, number of bubbles: 130 / mm ² , equilibrium water absorption: 24%)
Was prepared. The foamed polyurethane sheet was immersed in methyl methacrylate to which 0.1 parts by weight of azobisisobutylnitrile was added for 25 minutes. The foamed polyurethane sheet swollen with methyl methacrylate was sandwiched between glass plates and heated at 65 ° C. for 24 hours, and then heated at 100 ° C. for 3 hours. After heating, it was removed from the glass plate and vacuum dried at 50 ° C. The obtained hard foam sheet was ground on both sides to produce a polishing pad having a thickness of 1.2 mm. The resulting polishing pad has a micro rubber A hardness of 95 degrees and a density of 0.
The average diameter of closed cells was 180 μm, the number of cells was 112 / mm ² , the D hardness was 59 degrees, and the content of polymethyl methacrylate in the polishing pad was 64% by weight. The equilibrium water absorption was 7%. Cushion layer “Sub”
a400 ″ was bonded to the polishing pad to produce a composite polishing pad. A test wafer for global step evaluation was attached to a polishing head of a polishing machine and rotated at 45 rpm to fix the composite polishing pad to a platen of the polishing machine. 4
Polishing is performed at a polishing pressure of 0.04 MPa while supplying the slurry “SC-1” at 35 cc / min (0.031 cc / min per 1 cm ² area of the polishing pad) while rotating the polishing head at 5 rpm in the same direction as the rotation direction of the polishing head. did. 20 μm wide wiring area and 23
The polishing time when the global step in the 0 μm width wiring region became 0.2 μm was 7 minutes. Further, the test wafer for dust and scratch evaluation was attached to the polishing head of the polishing machine and rotated at 45 rpm, and the composite polishing pad was fixed to the platen of the polishing machine, and rotated at 45 rpm in the same direction as the rotation direction of the polishing head. Slurry “SC”
-1 "was supplied at a rate of 35 cc / min (0.031 cc / min per 1 cm ² area of the polishing pad) while the polishing pressure was 0.04.
Polishing was performed at MPa. The number of dusts on the wafer was as large as 60, and one scratch was observed. Further, a test wafer for evaluating tungsten wiring dishing was attached to a polishing head of a polishing machine and rotated at 45 rpm, and the composite polishing pad was fixed to a platen of the polishing machine, and rotated at 45 rpm in the same direction as the rotation direction of the polishing head. Polishing was performed at a polishing pressure of 0.04 MPa while supplying a slurry for tungsten manufactured by Co., Ltd. at 35 cc / min (0.031 cc / min per 1 cm ² area of the polishing pad). The tungsten wiring (100 μm
Width) The dishing depth at the center was 0.13 μm.

Comparative Example 2 78 parts by weight of a polyether urethane polymer (Adiprene L-325 manufactured by Uniroyal Co.) and 4,4′-methylene-
Twenty parts by weight of bis 2-chloroaniline is mixed with a RIM molding machine, and further mixed with hollow polymer microspheres (Expancel 551).
DE) 1.8 parts by weight are mixed, discharged into a mold and subjected to pressure molding to form a 2.2 mm thick foamed polyurethane sheet (micro rubber A hardness = 95 degrees, density: 0.83, closed cell average diameter: 30 μm, number of bubbles: 655 / mm 2, equilibrium water absorption: 4%). The obtained hard foam sheet was ground on both sides to prepare a polishing pad having a thickness of 1.2 mm. The D hardness was 60 degrees. Cushion layer “Suba
400 "was bonded to the polishing pad to produce a composite polishing pad. A test wafer for global step evaluation was attached to a polishing head of a polishing machine and rotated at 45 rpm.
The composite polishing pad is fixed to a platen of a polishing machine, and 45r
pm, the slurry “SC-1” is rotated at 35 cc / min (polishing pad 1 cm
Polishing was performed at a polishing pressure of 0.04 MPa while supplying at a rate of 0.031 cc / min per two areas). 20 μm wide wiring area and 230 μm of global level difference test wafer
The global step in the width wiring region became 0.2 μm, and the polishing time was 8 minutes. A test wafer for dust and scratch evaluation was attached to the polishing head of
By rotating the composite polishing pad on a platen of a polishing machine at 45 rpm and rotating in the same direction as the rotation of the polishing head at 45 rpm, a slurry "SC-1" manufactured by Cabot Corporation was rotated.
35 cc / min (0.0 per cm 2 area of polishing pad)
Polishing pressure 0.04MPa while supplying at 31cc / min)
Was polished. The number of dusts on the wafer was as large as 70, and one scratch was observed. Further, a test wafer for evaluating tungsten wiring dishing was attached to a polishing head of a polishing machine and rotated at 45 rpm, and the composite polishing pad was fixed to a platen of the polishing machine, and rotated at 45 rpm in the same direction as the rotation direction of the polishing head. Polishing was performed at a polishing pressure of 0.04 MPa while supplying a slurry for tungsten manufactured by Co., Ltd. at 35 cc / min (0.031 cc / min per 1 cm 2 area of the polishing pad). Table 1 shows the evaluation results of Examples and Comparative Examples in which the dishing depth at the center of the tungsten wiring (100 μm width) when the oxide film surface was exposed was 0.10 μm.

[0063]

[Table 1]

[0064]

According to the present invention, there is little dust adhesion and scratching, the polishing rate is high, the global step is small, dishing in metal wiring hardly occurs, clogging and sagging of the surface layer hardly occur. A polishing pad with a stable rate could be provided.

 ──────────────────────────────────────────────────続 き Continued on front page F term (reference) 3C058 AA07 AA09 CA01 CB01 CB03 4F071 AA33 AA53 AF22 AF25 AH19 DA19 DA20 4J002 BG05X BG06X BG07X CD19X CK04W CK05W GT00

Claims (7)

[Claims] 1. A micro rubber A having a hardness of 80 degrees or more, a number of closed cells in a range of 150 to 2500 (cells / mm ² ), and a density of 0.6 to 0.95 (g / cm ³ ). A polishing pad, wherein the polishing pad has an equilibrium water absorption of at least 5%. 2. The polishing pad according to claim 1, wherein the constituent material is mainly composed of polyurethane. 3. The polishing pad according to claim 1, wherein the constituent material comprises a polymer polymerized from polyurethane and a vinyl compound. 4. The polishing pad according to claim 3, wherein a polymer polymerized from a polyurethane and a vinyl compound is integrally contained. 5. The content ratio of a polymer polymerized from a polyurethane and a vinyl compound in the polymer is 60/40 to 60/40 by weight.
5. The polishing pad according to claim 3, wherein the ratio is 10/90. 6. The method according to claim 1, wherein the vinyl compound is CH ₂ ＣＲCR ¹ COOR.
² polishing pad according to any one of claims 3-5, characterized in that the (R ^1:: methyl group or an ethyl group, R ² a methyl group, an ethyl group, a propyl group or a butyl group). 7. The closed cell has an average cell diameter of 20 μm to 90 μm.
The polishing pad according to claim 1, wherein m is m.