Polishing pads and polishing methods

Abstract

To provide a polishing pad with excellent thermal stability. [Solution] The polishing pad includes a polishing layer, and in dynamic viscoelasticity measurements performed at a frequency of 1.6 Hz, the polishing layer does not have a peak temperature for the loss coefficient (tanδ) within the temperature range of 15°C to 120°C, and the rate of change of the tanδ value, calculated by the following formula for the tanδ value within the temperature range of 15°C to 120°C, is 20% or less. tanδ value change rate = |(maximum value of tanδ within the temperature range of 15℃ to 120℃) - (minimum value of tanδ within the temperature range of 15℃ to 120℃)| / (maximum value of tanδ within the temperature range of 15℃ to 120℃) × 100%

Description

Technical Field

[0001] The present invention relates to a polishing pad and a polishing method, and particularly relates to a polishing pad with excellent thermal stability and an extended service life, and a polishing method using the polishing pad.

Background Art

[0002] In the process of manufacturing industrial elements, the polishing process is currently a relatively commonly used technology for planarizing the surface of a workpiece to be polished. In the polishing process, the object is planarized by the relative movement between itself and the polishing pad, and selectively providing a polishing liquid between the object surface and the polishing pad. Therefore, the physical properties of the polishing pad are one of the factors affecting the polishing effect or performance.

[0003] The loss factor (tanδ) can reflect the physical properties of the polishing pad. This is the ratio of the loss modulus E’’ (viscous component) to the storage modulus E’ (elastic component), and represents that under the measurement conditions, it is an index of the balance between the elasticity and viscosity exhibited by the measured substance. Currently, Taiwan Patent Publication No. 202228917 and Japanese Patent Laid-Open No. 2021-053760 both disclose that the polishing effect or performance can be adjusted by the polishing pad having a specific tanδ value within a specific temperature range. The polishing pad disclosed in Taiwan Patent Publication No. 202228917 can provide excellent flatness to the workpiece to be polished, and the polishing pad disclosed in Japanese Patent Laid-Open No. 2021-053760 can suppress the occurrence of polishing scratches.

[0004] However, these polishing pads already on the market cannot meet various specific requirements, such as high-temperature polishing processes (temperatures exceeding 60°C) or processes requiring thermal stability. Generally, the temperature of the polishing pad rises during the polishing process due to the heat generated by friction, and this temperature increase easily causes changes in the physical properties of the polishing pad, further affecting the polishing effect or performance. Therefore, there is still a need to provide polishing pads with excellent thermal stability and give the industry more options. [Overview of the project] [Problems that the invention aims to solve]

[0005] This invention provides a polishing pad with excellent thermal stability.

[0006] The present invention further provides a polishing pad that has excellent thermal stability and is less susceptible to changes in its physical properties due to temperature increases during the polishing process, that is, a polishing pad whose physical properties do not change easily even under different temperature conditions.

[0007] The present invention further provides a polishing method in which the polishing pad can maintain a stable polishing speed during the polishing process and has an extended service life. [Means for solving the problem]

[0008] The polishing pad of the present invention includes a polishing layer. In dynamic viscoelasticity measurements performed at a frequency of 1.6 Hz, the polishing layer does not have a peak temperature for the loss coefficient (tanδ) within the temperature range of 15°C to 120°C, and the rate of change of tanδ, calculated by the following formula for the tanδ value within the temperature range of 15°C to 120°C, is 20% or less. Rate of change of tanδ = |(Maximum value of tanδ within the temperature range of 15°C to 120°C) - (Minimum value of tanδ within the temperature range of 15°C to 120°C)| / (Maximum value of tanδ within the temperature range of 15°C to 120°C) × 100%.

[0009] Another polishing pad of the present invention includes a polishing layer. In dynamic viscoelasticity measurements performed at a frequency of 1.6 Hz, the polishing layer does not have a tanδ peak value temperature within the temperature range of 15°C to 120°C, and in dynamic viscoelasticity measurements performed at a frequency of 1.6 Hz, the ratio of the storage modulus of the polishing layer in a water-absorbed state to the storage modulus of the dry state at any temperature within the temperature range of 30°C to 65°C is 0.9 to 1.0.

[0010] The polishing method of the present invention comprises the following steps: Provide a polishing pad. Here, the polishing pad is one of the polishing pads described above. Apply pressure to an object and press it onto the polishing pad. Provide relative motion between the object and the polishing pad to perform the polishing process. [Effects of the Invention]

[0011] As described above, the polishing pad of the present invention, in dynamic viscoelasticity measurements performed at a frequency of 1.6 Hz and a temperature range of 15°C to 120°C, does not have a tanδ peak value temperature, and the rate of change of tanδ value, as determined by the above formula, is 20% or less. By including this polishing layer, the polishing pad can have excellent thermal stability. In this way, when an object is polished using the polishing pad of the present invention, a stable polishing speed can be maintained, and furthermore, excellent polishing quality and an extended service life can be provided.

[0012] Furthermore, the polishing pad of the present invention includes a polishing layer in which, in dynamic viscoelasticity measurements performed at a frequency of 1.6 Hz and a temperature range of 15°C to 120°C, there is no tanδ peak value temperature, and in dynamic viscoelasticity measurements performed at a frequency of 1.6 Hz, the ratio of storage modulus in different states (water-absorbing state and dry state) at any temperature within the temperature range of 30°C to 65°C is 0.9 to 1.0. As a result, the polishing pad not only has excellent thermal stability, but its physical properties do not change easily even under different usage conditions. In this way, the polishing pad of the present invention can meet the requirements of different polishing processes in industry, maintain a stable polishing speed during the polishing period, and further provide excellent polishing quality and an extended service life.

[0013] To make the above-mentioned features and advantages of the present invention easier to understand, embodiments are described below in detail in conjunction with the accompanying drawings. [Brief explanation of the drawing]

[0014] [Figure 1] This is a flowchart of a polishing method according to one embodiment of the present invention. [Figure 2] This diagram shows the relationship between temperature and tanδ in the dynamic viscoelasticity measurement of the bending mode of the polishing pad in the dry state of Sample 1. [Figure 3] This diagram shows the relationship between temperature and storage modulus of dynamic viscoelasticity measurement of the bending mode of the abrasive pad of Sample 1 in both dry and water-absorbed states. [Figure 4] This diagram shows the relationship between temperature and tanδ when dynamic viscoelasticity measurements were performed in the bending and tensile modes on the polishing pad of Sample 2 in a dry state. [Figure 5] This diagram shows the relationship between temperature and tanδ when dynamic viscoelasticity measurements were performed in the bending and tensile modes on the polishing pad of Sample 2 in a water-absorbed state. [Modes for carrying out the invention]

[0015] In this text, the range indicated by "from one number to another number" is a general representation to avoid listing each number within that range individually in the specification. Therefore, the description of a particular numerical range includes any number within that range and any smaller numerical range defined by any number within that range, and is equivalent to specifying that any number and smaller numerical range in the specification.

[0016] As used in this text, "about" includes the mean value within an acceptable range of deviations of the stated value and any specific value determined by a person skilled in the art, taking into account the measurement and any specific amount of error associated with the measurement (i.e., the limits of the measurement system). For example, "about" can mean within one or more standard deviations of the stated value, or within, for example, ±30%, ±20%, ±15%, ±10%, ±5%. Furthermore, as used in this text, "about" or "substantially" may mean that a more acceptable range of deviations or standard deviations can be selected depending on the nature of the measurement or other properties, and it is not necessary to apply one standard deviation to all properties.

[0017] In this embodiment, the polishing pad includes an abrasive layer. That is, in this embodiment, the polishing pad is a single-layer polishing pad. However, the present invention is not limited thereto. In other embodiments, the polishing pad may further include a base layer or an adhesive layer.

[0018] In this embodiment, in dynamic viscoelasticity measurements performed at a frequency of 1.6 Hz, the polished layer does not have a peak temperature for the loss coefficient (tanδ) within the temperature range of 15°C to 120°C. The so-called "tanδ peak temperature" refers to the temperature at which tanδ reaches its peak value in the tanδ distribution curve. Furthermore, a tanδ peak value means that the value of tanδ increases before a certain temperature, but decreases after that temperature, and a peak value of tanδ exists. In this embodiment, within the temperature range of 15°C to 120°C, the tanδ distribution curve of the polished layer is flat, and no clear peak appears (meaning that the value of tanδ increases before a certain temperature, but decreases after that temperature). Also, in this embodiment, in dynamic viscoelasticity measurements performed at a frequency of 1.6 Hz, the rate of change of the tanδ value of the polished layer within the temperature range of 15°C to 120°C, calculated by the following formula, is 20% or less. The rate of change of tanδ value = |(maximum value of tanδ within the temperature range of 15℃ to 120℃) - (minimum value of tanδ within the temperature range of 15℃ to 120℃)| / (maximum value of tanδ within the temperature range of 15℃ to 120℃) × 100%. In other words, in this embodiment, within a specific temperature range, the polished layer has a tanδ with small numerical fluctuations.

[0019] Since tanδ is an indicator of the balance between elasticity and viscosity exhibited by the material being measured under the measurement conditions, the polishing layer does not have a tanδ peak value temperature within a specific temperature range (i.e., a temperature range of 15°C to 120°C), and the rate of change of tanδ value is 20% or less. This indicates that the physical properties (e.g., thermal properties) of the polishing layer do not change significantly due to temperature changes. In other words, in this embodiment, the polishing pad can have excellent thermal stability. Thus, when an object is polished using the polishing pad of this embodiment, a stable polishing speed can be maintained, and furthermore, excellent polishing quality and an extended service life can be provided, making it particularly applicable to high-temperature polishing processes.

[0020] As measurement modes in dynamic viscoelasticity measurement, a tensile mode, a bending mode, a compression mode, etc. are known. In the present embodiment, the dynamic viscoelasticity measurement performed on the polishing layer under the conditions of a frequency of 1.6 Hz and a temperature range of 15°C to 120°C may be in the tensile mode or the bending mode. That is, in the present embodiment, the physical properties of the polishing layer (i.e., the measurement results) do not change even when measured using different measurement modes.

[0021] Viewed from another perspective, in the present embodiment, in the dynamic viscoelasticity measurement performed at a frequency of 1.6 Hz, the absolute value of the slope within the temperature range of 15°C to 120°C of the distribution curve of the temperature of the polishing layer and the tanδ value is less than about 5. That is, in the present embodiment, within a specific temperature range, the polishing layer has a tanδ with small numerical fluctuations. From the perspective of improving the thermal stability of the polishing pad, it is preferable that the absolute value of the slope within the temperature range of 45°C to 100°C of the distribution curve of the temperature of the polishing layer and the tanδ value approaches 0. That is, the physical properties of the polishing layer of the polishing pad are hardly affected by temperature changes. During actual CMP application, the temperature change range of the polishing layer is generally within the temperature range of 25°C to 70°C, but the polishing layer of the present invention is hardly affected by temperature changes within this temperature range, and it is possible to surely guarantee that the physical properties of the polishing layer do not easily change during the CMP polishing process. Therefore, not only can a constant polishing rate be maintained, but also the service life of the polishing pad can be extended.

[0022] In the present embodiment, the tanδ value of the polishing layer within the temperature range of 15°C to 120°C is less than 0.1. Such a low tanδ value means that the material has a relatively low loss elastic modulus and a relatively high storage elastic modulus, indicating that the energy consumption in the deformation process of the material is small and most of the energy is stored and not converted into thermal energy. Therefore, the material has relatively high elastic recovery, and when applied to the polishing process, the elasticity of the material can recover more quickly between consecutive polishing passes, thereby improving the polishing efficiency.

[0023] Also, in the present embodiment, in the dynamic viscoelasticity measurement performed at a frequency of 1.6 Hz, the ratio of the storage modulus in the water absorption state to the storage modulus in the dry state at any temperature within the temperature range of 30°C to 65°C of the polishing layer is 0.9 to 1.0. In one embodiment of the present invention, the "water absorption state" refers to a state in which the object to be measured (for example, the polishing layer) is immersed in deionized water at 15°C to 40°C for 18 hours to 36 hours and the surface moisture is wiped off. In one embodiment of the present invention, the "dry state" refers to a state in which the object to be measured (for example, the polishing layer) is placed in a normal atmospheric environment. That is, in the present embodiment, when the surface state of the polishing layer in contact with the object to be measured is different, the physical properties of the surface (that is, the measurement results) do not change or change little.

[0024] In some embodiments, the polishing process includes planarization by a chemical action brought about by a polishing liquid supplied between the polished surface of an object and a polishing pad. During the polishing process described above, the surface of the polishing layer in contact with the object can be regarded as being in the "water absorption state". In some other embodiments, the polishing process does not require supplying a polishing liquid between the polished surface of the object and the polishing pad for planarization. During the polishing process described above, the surface of the polishing layer in contact with the object can be regarded as being in the "dry state". In this way, since the physical properties of the polishing layer of the present embodiment are less likely to change significantly due to changes in its surface state, it can meet the requirements of different polishing processes in the industry and provide excellent polishing quality.

[0025] In the present embodiment, from the perspective of improving the thermal stability of the polishing pad, the ratio (E'30 / E'50) of the storage modulus (E'30) of the dynamic viscoelasticity measurement performed at 30°C of the polishing layer to the storage modulus (E'50) of the dynamic viscoelasticity measurement performed at 50°C is more preferably less than about 1.5, and even more preferably less than about 1.3.

[0026] In this embodiment, from the viewpoint of improving the thermal stability of the polishing pad, the ratio (E'30 / E'90) of the storage modulus of elasticity measured at 30°C in the polishing layer to the storage modulus of elasticity measured at 90°C is more preferably less than 2.5, and even more preferably less than about 2.0.

[0027] Furthermore, in this embodiment, in dynamic viscoelasticity measurements performed at a frequency of 1.6 Hz, the value of the storage modulus (E') of the polished layer within the temperature range of 15°C to 120°C is not limited, but it is more preferably about 100 MPa to about 720 MPa. In the embodiment of the present invention, by adjusting the values ​​of the loss modulus E'' and the storage modulus E', the rate of change of the ratio of the loss modulus E'' to the storage modulus E' (i.e., the tanδ value) can be reduced to 20% or less. In other words, as long as the rate of change of the tanδ value is 20% or less, the values ​​of the loss modulus E'' and the storage modulus E' are not particularly limited.

[0028] In this embodiment, the material of the abrasive layer of the polishing pad is not particularly limited, as long as the measurement results of the dynamic viscoelasticity measurement of the abrasive layer satisfy the conditions described above. In this embodiment, the abrasive layer is composed of a polymer foam. Here, the polymer foam may be polyurea, polyurethane, urea / urethane copolymer, or a combination thereof. However, the present invention is not limited thereto. In other embodiments, the abrasive layer may contain conductive materials, abrasive particles, microspheres, or soluble additives in addition to the polymer foam.

[0029] In one embodiment, the polymer foam comprises a reaction mixture formed by an isocyanate-terminated prepolymer and a curing agent. Here, the isocyanate-terminated prepolymer is formed by an isocyanate compound and a polyol. In one embodiment, the isocyanate compound includes an aliphatic isocyanate compound, an alicyclic isocyanate compound, or a combination thereof. Examples of isocyanate compounds include isophorone diisocyanate (IPDI) and dicyclohexylmethane diisocyanate (H 12 It includes MDI, hexamethylene diisocyanate (HDP). It should be noted that, in this embodiment, the use of an aliphatic isocyanate compound to produce the polishing layer helps to improve the yellowing resistance of the polishing pad, and therefore the polishing pad can be applied to copper processes.

[0030] Furthermore, polyols include, for example, diol compounds such as ethylene glycol, diethylene glycol (DEG), and butanediol, triol compounds, etc.; polyether polyol compounds such as polypropylene glycol (PPG) and poly(oxytetramethylene)diol (PTMG); polyester polyol compounds such as the reaction product of ethylene glycol and adipic acid or the reaction product of butanediol and adipic acid; polycarbonate polyol compounds, and polycaprolactone polyol compounds. In one embodiment of this invention, the curing agent may be a polyamine compound, and may be at least one selected from the group consisting of aliphatic amine compounds and aromatic amine compounds, for example. Examples of polyamine compounds include polyetheramine, diethyltoluenediamine (DETDA), dimethylthiotoluenediamine (DMTDA), etc.

[0031] Furthermore, in this embodiment, a groove pattern may be included on the surface of the polishing layer that comes into contact with the object (i.e., the polishing surface), and the groove pattern may have a variety of different pattern distributions, such as concentric rings, non-concentric rings, elliptic rings, wavy rings, irregular rings, multiple linear patterns, parallel linear patterns, radial linear patterns, radial arc patterns, spiral patterns, polygonal grid patterns, or combinations thereof, but the present invention is not limited thereto.

[0032] The base layer is used to support the polishing layer within the polishing pad. The material of the base layer may be, but is not limited to, polyurethane, polybutadiene, polyethylene, polypropylene, a copolymer of polyethylene and ethylene vinyl acetate, or a copolymer of polypropylene and ethylene vinyl acetate.

[0033] The adhesive layer is placed between the polishing layer and the base layer and is used to bond the polishing layer and the base layer. The adhesive layer includes, for example, a carrier-free adhesive, double-sided tape, hot-melt adhesive, or moisture-curing adhesive (but is not limited to these). The material of the adhesive layer is, for example, an acrylic adhesive, a silicone adhesive, a rubber adhesive, an epoxy resin adhesive, or a polyurethane adhesive, but is not limited to these.

[0034] Figure 1 is a flowchart of a polishing method according to one embodiment of the present invention. This polishing method is applied to the polishing of objects. More specifically, this polishing method can be applied to polishing processes for manufacturing industrial elements, for example, to elements in the electronics industry, including elements such as semiconductors, integrated circuits, micro-electromechanical systems, energy conversion, communications, optics, memory disks, and displays. The objects used in the manufacture of these elements may include, but are not limited to, semiconductor wafers, III-V wafers, memory element carriers, ceramic substrates, polymer substrates, and glass substrates.

[0035] Referring to Figure 1, first, step S10 is performed to provide the polishing pad. More specifically, in this embodiment, the polishing pad includes the polishing layer of any of the embodiments described above. Further details regarding the polishing pad have been explained in detail in the preceding paragraph and will not be repeated here.

[0036] Next, step S20 is performed to apply pressure to the object. This presses the object against the polishing pad, causing it to come into contact with the polishing pad. More specifically, as mentioned earlier, the object comes into contact with the polishing surface within the polishing layer. The method of applying pressure to the object is, for example, by using a carrier capable of holding the object.

[0037] Subsequently, step S30 is performed to provide relative motion to the object and the polishing pad, thereby using the polishing pad to perform a polishing process on the object and achieving the objective of planarization. More specifically, a method of providing relative motion to the object and the polishing pad is, for example, a method of rotating the polishing platform so that the polishing pad fixed on the polishing platform rotates.

[0038] To demonstrate that the polishing pad proposed in this invention has excellent thermal stability, we conducted an experiment measuring dynamic viscoelasticity. The measurement method and sample setup used in the experiment are as follows.

[0039] Sample 1 and Sample 2: Both Sample 1 and Sample 2 are single-layer polishing pads (i.e., polishing pads containing a polishing layer), and the aforementioned polishing layer is dicyclohexylmethane diisocyanate (H 12 This is a polyurethane foam formed by the reaction of an isocyanate-terminated prepolymer (MDI) and poly(oxytetramethylene)diol (PTMG) with the curing agent diethyltoluenediamine (DETDA). Samples 1 and 2 have the same material formulation but are completed in different injection batches.

[0040] [Dynamic viscoelasticity measurement of bending modes in a water-absorbed state]

[0041] First, the polishing pads of Sample 1 and Sample 2 were kept in a constant temperature and humidity chamber at 23°C (±2°C) and 50% relative humidity (±5%) for 40 hours. Next, the polishing pads of Sample 1 and Sample 2 were immersed in deionized water at 25°C for 24 hours, after which the moisture on the surface of the polishing layer was wiped off. Subsequently, dynamic viscoelasticity measurements in the bending mode were performed on the polishing layer under the following conditions. The dynamic viscoelasticity measuring device used was a Waters TA product named "Q800". Sample size: Length 35mm x Width 12.5-13.5mm (width varies depending on the blade type) Test mode: 3-point bending Frequency: 1.6Hz Temperature range: 25℃~150℃ Heating rate: 2°C / min Amplitude: 20±1μm Initial load: 0g Measurement interval: 1 point / °C

[0042] [Dynamic viscoelasticity measurement of bending modes in a dry state]

[0043] First, polishing pads for Sample 1 and Sample 2 were kept in a constant temperature and humidity chamber at 23°C (±2°C) and 50% relative humidity (±5%) for 40 hours. Next, dynamic viscoelasticity measurements in the bending mode were performed on the polishing layers under normal atmospheric conditions. The dynamic viscoelasticity measuring device used was a Waters TA product named "Q800". Sample size: Length 35mm x Width 12.5-13.5mm (width varies depending on the blade type) Test mode: 3-point bending Frequency: 1.6Hz Temperature range: 25℃~150℃ Heating rate: 2°C / min Amplitude: 20±1μm Initial load: 0g Measurement interval: 1 point / °C

[0044] [Dynamic viscoelasticity measurement of the tensile mode under water absorption]

[0045] First, the polishing pads of Sample 1 and Sample 2 were kept in a constant temperature and humidity chamber at 23°C (±2°C) and 50% relative humidity (±5%) for 40 hours. Next, the polishing pads of Sample 1 and Sample 2 were immersed in deionized water at 25°C for 24 hours, after which the moisture on the surface of the polishing layer was wiped off. Subsequently, dynamic viscoelasticity measurements in tensile mode were performed on the polishing layer under the following conditions. The dynamic viscoelasticity measuring device used was a Waters TA product named "Q800". Sample size: Length 8.0-8.2mm x Width 5.45-5.70mm (may vary depending on the blade type) Frequency: 1.6Hz Temperature range: 25℃~150℃ Heating rate: 2°C / min Amplitude: 20±1μm Tensile load: 0.01N Dynamic distortion: 125% Measurement interval: 1 point / °C

[0046] [Dynamic viscoelasticity measurement in tensile mode under dry conditions]

[0047] First, polishing pads of Sample 1 and Sample 2 were kept in a constant temperature and humidity chamber at 23°C (±2°C) and 50% relative humidity (±5%) for 40 hours. Next, dynamic viscoelasticity measurements in tensile mode were performed on the polishing layers under normal atmospheric conditions. The dynamic viscoelasticity measuring device used was a Waters TA product named "Q800". Sample size: Length 8.0-8.2mm x Width 5.45-5.70mm (may vary depending on the blade type) Frequency: 1.6Hz Temperature range: 25℃~150℃ Heating rate: 2°C / min Amplitude: 20±1μm Tensile load: 0.01N Dynamic distortion: 125% Measurement interval: 1 point / °C

[0048] The results obtained from the dynamic viscoelasticity measurement experiments described above are shown in Figures 2 to 5. Figure 2 is a diagram showing the relationship between temperature and tanδ in the dynamic viscoelasticity measurement of the bending mode of the polishing pad of Sample 1 in a dry state; Figure 3 is a diagram showing the relationship between temperature and storage modulus in the dynamic viscoelasticity measurement of the bending mode of the polishing pad of Sample 1 in a dry state and a water-absorbed state; Figure 4 is a diagram showing the relationship between temperature and tanδ in the dynamic viscoelasticity measurement of the bending mode and a tension mode of the polishing pad of Sample 2 in a dry state; and Figure 5 is a diagram showing the relationship between temperature and tanδ in the dynamic viscoelasticity measurement of the bending mode and a tension mode of the polishing pad of Sample 2 in a water-absorbed state.

[0049] As can be clearly seen from Figure 2, within the temperature range of 15°C to 120°C, the tanδ distribution curve of the polishing pad of Sample 1 is very flat, with an absolute value of the slope less than approximately 5, and within the temperature range of 45°C to 100°C, the absolute value of the slope approaches 0. Furthermore, the tanδ distribution curve shown in Figure 2 does not show a clear peak (i.e., the tanδ value increases before a certain temperature, but decreases beyond that temperature). In other words, the polishing pad of Sample 1 does not have a peak temperature for the loss coefficient (tanδ) within the temperature range of 15°C to 120°C. Also, as can be seen from Figure 2, the tanδ value within the temperature range of 15°C to 120°C is less than 0.1, so it falls in the interval of 0.06 to 0.08. Also, as can be seen from Figure 2, the rate of change of the tanδ value within the temperature range of 15°C to 120°C, calculated by the following formula, is 20% or less. The rate of change of tanδ value = |(maximum value of tanδ within the temperature range of 15℃ to 120℃) - (minimum value of tanδ within the temperature range of 15℃ to 120℃)| / (maximum value of tanδ within the temperature range of 15℃ to 120℃) × 100%.

[0050] The results in Figure 2 demonstrate that the polishing pad of this embodiment has excellent thermal stability within a temperature range of 15°C to 120°C. When polishing an object using the polishing pad of this embodiment, a stable polishing speed can be maintained, and furthermore, excellent polishing quality and extended service life can be provided, making it particularly applicable to high-temperature polishing processes.

[0051] As can be clearly seen from Figure 3, the ratio of the storage modulus of the polishing pad in a water-absorbed state to the storage modulus of the dry state at any temperature within the temperature range of 30°C to 65°C is 0.9 to 1.0. This indicates that the change in the storage modulus of the polishing pad is very small under different usage conditions (water absorption and dryness), and that it has excellent thermal stability. This feature is extremely important in the CMP polishing process. This is because, in the CMP polishing process, the surface of the polishing pad is wetted by the polishing fluid, but the storage modulus of the polishing pad in this embodiment does not change significantly even when the surface of the polishing pad is wet, and it can maintain stable physical properties during the polishing process. Therefore, it can meet the requirements of various types of different polishing processes, maintain a stable polishing speed during the polishing period, and furthermore, provide excellent polishing quality and an extended service life.

[0052] As can be seen from Figures 4 and 5, regardless of whether the pad is dry or wet, and regardless of whether the water absorption is measured in bending mode or tensile mode, none of the polishing pads of Sample 2 exhibit a tanδ peak temperature within the measured temperature range. Furthermore, the tanδ distribution curves under different conditions all show very similar trends. This indicates that, even under different usage conditions, the physical properties of the polishing layer of the polishing pad of the present invention do not change significantly due to temperature changes. In other words, the polishing pad of the present invention can exhibit excellent thermal stability under different usage conditions.

[0053] Furthermore, although Sample 1 and Sample 2 are completed in different injection batches, the results in Figures 2 to 5 demonstrate that the polishing layer of the polishing pad of the present invention exhibits consistent physical properties even when produced in different batches, that is, the physical properties are reproducible.

[0054] The present invention is disclosed by the embodiments described above, but this does not limit the invention. Those skilled in the art can make some modifications and changes without departing from the spirit and scope of the invention, so the scope of protection of the present invention shall be as defined by the claims appended later. [Industrial applicability]

[0055] The polishing pad and polishing method of the present invention can be used in the polishing process in the manufacturing process of an element. [Explanation of Symbols]

[0056] S10, S20, S30 Step

Claims

1. A polishing pad including an abrasive layer, In dynamic viscoelasticity measurements performed at a frequency of 1.6 Hz, the polished layer does not have a peak temperature for the loss coefficient (tanδ) within the temperature range of 15°C to 120°C. The rate of change of the tanδ value, calculated using the following formula for the tanδ value within the temperature range of 15°C to 120°C, is 20% or less. A polishing pad where the tanδ value change rate = |(maximum value of tanδ within the temperature range of 15°C to 120°C) - (minimum value of tanδ within the temperature range of 15°C to 120°C)| / (maximum value of tanδ within the temperature range of 15°C to 120°C) × 100%.

2. The polishing pad according to claim 1, wherein the dynamic viscoelasticity measurement performed at a frequency of 1.6 Hz is a dynamic viscoelasticity measurement in the bending mode.

3. The polishing pad according to claim 1, wherein the dynamic viscoelasticity measurement performed at a frequency of 1.6 Hz is a dynamic viscoelasticity measurement in tensile mode.

4. The polishing pad according to any one of claims 1 to 3, wherein the tanδ value of the polishing layer within a temperature range of 15°C to 120°C is less than 0.

1.

5. The polishing pad according to any one of claims 1 to 3, wherein the ratio (E'30 / E'50) of the storage modulus of the polishing layer measured at 30°C (E'30) to the storage modulus of the polishing layer measured at 50°C (E'50) is less than 1.

5.

6. The polishing pad according to any one of claims 1 to 3, wherein the ratio (E'30 / E'90) of the storage modulus of the polishing layer measured at 30°C (E'30) to the storage modulus of the polishing layer measured at 90°C (E'90) is less than 2.

5.

7. The polishing pad according to any one of claims 1 to 3, wherein, in a dynamic viscoelasticity measurement performed at a frequency of 1.6 Hz, the storage modulus (E') of the polishing layer within a temperature range of 15°C to 120°C is 100 MPa to 720 MPa.

8. The polishing pad according to any one of claims 1 to 3, wherein, in the dynamic viscoelasticity measurement performed at a frequency of 1.6 Hz, the absolute value of the slope of the distribution curve of the temperature of the polishing layer and the tanδ value within the temperature range of 15°C to 120°C is less than 5.

9. A polishing pad including an abrasive layer, In dynamic viscoelasticity measurements performed at a frequency of 1.6 Hz, the polished layer does not have a tanδ peak temperature within the temperature range of 15°C to 120°C. An abrasive pad in which, in the dynamic viscoelasticity measurement performed at a frequency of 1.6 Hz, the ratio of the storage modulus of the abrasive layer in a water-absorbed state to the storage modulus of the dry state at any temperature within the temperature range of 30°C to 65°C is 0.9 to 1.

0.

10. The polishing pad according to claim 9, wherein the tanδ value of the polishing layer within a temperature range of 15°C to 120°C is less than 0.

1.

11. The polishing pad according to claim 9, wherein the ratio (E'30 / E'50) of the storage modulus of the polishing layer measured at 30°C (E'30) to the storage modulus of the polishing layer measured at 50°C (E'50) is less than 1.

5.

12. The polishing pad according to claim 9, wherein the ratio (E'30 / E'90) of the storage modulus of the polishing layer measured at 30°C (E'30) to the storage modulus of the polishing layer measured at 90°C (E'90) is less than 2.

5.

13. The polishing pad according to claim 9, wherein, in a dynamic viscoelasticity measurement performed at a frequency of 1.6 Hz, the storage modulus (E') of the polishing layer within a temperature range of 15°C to 120°C is 100 MPa to 720 MPa.

14. The polishing pad according to claim 9, wherein, in the dynamic viscoelasticity measurement performed at a frequency of 1.6 Hz, the absolute value of the slope of the distribution curve of the temperature of the polishing layer and the tanδ value within the temperature range of 15°C to 120°C is less than 5.

15. The steps of providing a polishing pad according to claim 1 or 9, The steps include applying pressure to an object and pressing it onto the polishing pad, A step of providing relative motion to the object and the polishing pad to perform a polishing process, Polishing methods, including those mentioned above.

Images