Method for refurbishing a polishing pad, method for manufacturing a semiconductor element, and manufacturing apparatus

Abstract

This invention relates to a method for refurbishing polishing pads. By increasing the lifespan of the polishing pads used in the polishing process, the number of discarded polishing pads can be reduced, and the time required for polishing pad replacement can be shortened, thereby significantly improving polishing efficiency. Furthermore, the semiconductor device manufacturing method according to this application utilizes the aforementioned polishing pad refurbishment method to achieve polishing performance comparable to new polishing pads, enabling repeated use and improving process efficiency by reducing the number of polishing pad replacements.

Description

Technical Field

[0001] This invention relates to a method for refurbishing a polishing pad, and to a method for manufacturing a semiconductor device using the polishing pad refurbishment method, as well as an apparatus for manufacturing a semiconductor device. Background Technology

[0002] Chemical mechanical planarization (CMP) or chemical mechanical polishing (CMP) processes can be used for various purposes in a variety of technical fields. CMP processes treat a specified surface of the object to be polished as the polishing target and can be performed for purposes such as planarizing the polished surface, removing aggregated material, eliminating lattice damage, and removing scratches and contaminants.

[0003] CMP (Chemical Metallurgy) processes in semiconductor manufacturing can be classified based on the film material being polished or the surface shape after polishing. For example, based on the film material, they can be categorized as single-crystal silicon or polycrystalline silicon. Based on the type of impurities, they can be classified as CMP processes using various oxide films or metal films such as tungsten (W), copper (Cu), aluminum (Al), ruthenium (Ru), and tantalum (Ta). Furthermore, based on the surface shape after polishing, they can be categorized as processes for improving substrate surface roughness, processes for planarizing steps caused by multilayer circuit wiring, and component separation processes for selectively forming circuit wiring after polishing.

[0004] CMP (Chemical Motion Processing) can be used multiple times during the manufacturing of semiconductor devices. Semiconductor devices can comprise multiple layers, each containing complex and intricate circuit patterns. Furthermore, in recent semiconductor devices, the size of individual chips has decreased, and the patterns of each layer have evolved towards greater complexity and finer detail. Therefore, in the manufacturing process of semiconductor devices, the purpose of CMP has expanded beyond just planarizing circuit traces to include separating circuit traces and improving trace surfaces, resulting in a demand for more precise and reliable CMP performance.

[0005] The polishing pad used in this CMP process is a process component that uses friction to process the polished surface to the required level. It can be regarded as one of the most important factors in terms of the uniformity of the thickness of the polished object, the flatness of the polished surface, and the polishing quality.

[0006] The polishing pads used in the CMP process take the specified polishing surface of the polishing object as the polishing object, and perform the polishing process with the purpose of planarizing the polishing surface, removing aggregated substances, eliminating lattice damage, and removing scratches and contaminants. If the polishing performance of the polishing pads decreases due to repeated polishing processes, the polishing pads need to be replaced, and the used polishing pads may be discarded.

[0007] Used polishing pads cannot be reused, and their disposal can cause environmental pollution. To prevent this problem, a method for handling polishing pads that can be used in the polishing process for a longer period than existing pads is needed. Summary of the Invention

[0008] The problem the invention aims to solve

[0009] The purpose of this invention is to provide a method for refurbishing polishing pads, which can reduce the amount of polishing pads discarded by increasing the service life of the polishing pads used in the polishing process.

[0010] Another object of the present invention is to provide a method for manufacturing semiconductor devices that can improve the service life of polishing pads by using the polishing pad refurbishment method and extend the replacement cycle of polishing pads in the polishing process, thereby significantly improving the efficiency of the semiconductor device manufacturing process.

[0011] Another object of the present invention is to provide a semiconductor device manufacturing apparatus that can improve the service life of polishing pads used in the polishing process.

[0012] means for solving problems

[0013] To achieve the above objectives, a method for refurbishing a polishing pad according to an embodiment of the present invention includes a step of supplying water vapor to the polishing pad, the polishing pad including a polishing layer having a polishing surface, the polishing layer including a plurality of pores, and the polishing surface including micro-recesses formed by the plurality of pores.

[0014] A method for manufacturing a semiconductor element according to another embodiment of the present invention includes: mounting a polishing pad including a polishing surface on a flat plate; placing a polishing object on the polishing surface such that its polished surface contacts the polishing surface; and, under pressure, rotating the polishing pad and the polishing object relative to each other and polishing the polishing object; and supplying water vapor to the polishing surface of the polishing pad.

[0015] A semiconductor element manufacturing apparatus according to another embodiment of the present invention includes: a plate for mounting a polishing pad; a carrier for mounting a semiconductor substrate; and a water vapor jet section for supplying water vapor to the polishing pad mounted on the plate.

[0016] Invention Effects

[0017] A method for refurbishing polishing pads is disclosed, which can reduce the amount of polishing pads discarded by increasing the lifespan of the polishing pads used in the polishing process.

[0018] Furthermore, by utilizing the polishing pad refurbishment method, the service life of the polishing pad can be improved, thereby reducing the number of times the polishing pad needs to be replaced during the polishing process, which can significantly improve the efficiency of the semiconductor device manufacturing process. Attached Figure Description

[0019] Figure 1 This is a flowchart of the polishing process.

[0020] Figure 2 It is a flowchart of a polishing process that includes a refurbishment method for polishing pads.

[0021] Figure 3 This is a conceptual diagram of three-dimensional surface roughness parameters.

[0022] Figure 4 This is a conceptual diagram of the surface roughness parameters Svk and Spk.

[0023] Figure 5 This is a diagram showing the shape changes of the micro-recesses formed on the polished surface of the polishing pad through a polishing process.

[0024] Figures 6A to 6D This is a conceptual diagram of a polishing apparatus according to an embodiment of the present invention.

[0025] Figure 7 This is a conceptual diagram of a polishing apparatus according to an embodiment of the present invention.

[0026] Figure 8 This is a 3D image of the surface of a polishing pad according to an embodiment of the present invention.

[0027] Figure 9 This is a 3D image of the surface of a polishing pad according to an embodiment of the present invention.

[0028] Figure 10 This is a SEM image of a polished surface according to an embodiment of the present invention.

[0029] Figure 11 This is a SEM image of a polished surface according to an embodiment of the present invention.

[0030] Figure 12 This is a SEM image of a polished surface according to an embodiment of the present invention.

[0031] Figure 13 This is a SEM image of a polished surface according to an embodiment of the present invention.

[0032] Explanation of reference numerals in the attached figures

[0033] 10: Polishing Pad Installation Steps

[0034] 20: Polishing process execution steps

[0035] 21: Slurry Injection Steps

[0036] 22: Adjustment steps

[0037] 30: Inspection steps regarding the time required for polishing

[0038] 31: Repeated steps of the polishing process

[0039] 32: Stopping steps for polishing processes that have exceeded the target polishing time.

[0040] 40: Step of spraying water vapor onto the polishing pad that is not within the target polishing time range.

[0041] 41: Adjustment steps

[0042] 42: Slurry Injection Steps

[0043] 50: Re-inspection steps regarding the time required for polishing

[0044] 51: Repeated steps of the polishing process

[0045] 52: Stopping steps for polishing processes that have exceeded the target polishing time.

[0046] 100: Polishing pad

[0047] 101: Polished layer

[0048] 102: Polished surface

[0049] 103: Stomata

[0050] 104: Micro concavity

[0051] 200: Tablet

[0052] 300: Nozzle section

[0053] 310: Slurry

[0054] 400: Carrier

[0055] 500: Semiconductor substrate

[0056] 600: Regulator

[0057] 700: Steam injection section

[0058] 710: Heated water vapor Detailed Implementation

[0059] The advantages and features of the present invention, as well as the methods of implementing them, will become clear from the following implementations or embodiments. However, the present invention is not limited to the implementations or embodiments disclosed below, but can be embodied in various forms that differ from each other. The following explicit implementations or embodiments are provided only to complete the disclosure of the present invention and to inform those skilled in the art of the scope of the invention, the scope of which is defined by the scope of the claims.

[0060] In the accompanying drawings, the thickness of certain components is shown enlarged as needed to clearly indicate layers or regions. Furthermore, the thickness of some layers and regions is exaggerated for ease of description. Throughout the specification, the same reference numerals refer to the same elements.

[0061] When a layer, film, region, plate, or other part is described as being "above" or "upper" another part in this specification, this includes not only the case where it is "directly above" the other part, but also the case where there are other parts in between. Describing a part as being "directly above" another part is interpreted as meaning that there are no other parts in between. Similarly, when a layer, film, region, plate, or other part is described as being "below" or "lower" of another part, this is interpreted as including not only the case where it is "directly below" the other part, but also the case where there are other parts in between. Describing a part as being "directly below" another part is interpreted as meaning that there are no other parts in between.

[0062] In this specification, when indicating a numerical range, "~ and above" is interpreted as including the corresponding number or more. For example, "2 and above" means two or more cases. Furthermore, the description of a numerical range as "X to Y" is interpreted as including a range of either X or Y. For example, "25 to 50" means a numerical range including 25 and 50.

[0063] In this specification, for any component modified by "first" or "second", its superordinate components are different from each other. Therefore, these are only modified and described in order to distinguish them, and these descriptions themselves are not to be construed as including mutually different components or different structures.

[0064] In this specification, "the state before water vapor is supplied to the polishing pad" refers to the state corresponding to either the state 1 to 10 minutes before the moment water vapor is supplied to the polishing pad or the state where the surface roughness (Sa) of the polished surface of the polishing pad is within 3 μm to 4.5 μm, or the state corresponding to both of these states.

[0065] In this specification, "the state after water vapor is supplied to the polishing pad" refers to the state after 1 to 10 minutes have elapsed since the water vapor supply was stopped.

[0066] In this specification, "polishing pad that fails to achieve the target polishing rate" refers to a polishing rate achieved under the following process conditions: calcined cerium dioxide slurry is supplied at a rate of 200 mL / min, pressure is applied to the semiconductor substrate to be polished at a load of 3.5 psi, and the silicon oxide film is polished for 60 seconds at a polishing pad rotation speed of 93 rpm and a semiconductor substrate rotation speed of 87 rpm. The following situations apply.

[0067] In this specification, "polishing pad that does not achieve the target polishing non-uniformity" refers to a polishing non-uniformity of 9% or less under the following process conditions: calcined cerium dioxide slurry is supplied at a rate of 200 mL / min, the semiconductor substrate to be polished is pressurized at a load of 3.5 psi, and the silicon oxide film is polished for 60 seconds at a speed of 93 rpm for the polishing pad and 87 rpm for the semiconductor substrate.

[0068] In this specification, "refresh" refers to the process of increasing the lifespan of polishing pads used in the polishing process, polishing pads that have not achieved the target polishing rate, and / or polishing pads that have not achieved the target polishing unevenness, through treatments such as i) supplying water vapor, or ii) supplying water vapor and adjustments.

[0069] In this specification, "continuous" refers to the time during which water vapor is supplied while the used polishing pad is mounted on the flat plate, and the time from when the semiconductor substrate used in the polishing process is removed from the carrier and a new semiconductor substrate is mounted on the carrier until the polishing process restarts.

[0070] In the following sections, exemplary implementations of the present invention will be described in detail.

[0071] One embodiment of the present invention provides a method for refurbishing a polishing pad, which includes the step of supplying water vapor to the polishing pad, the polishing pad including a polishing layer having a polishing surface, the polishing layer including a plurality of pores, and the polishing surface 102 including micro-recesses 104 formed by the plurality of pores 103.

[0072] Figure 1This is a flowchart of the polishing process. Specifically, a polishing pad is mounted on the upper part of the flat plate, and a semiconductor substrate is mounted on the carrier (step 10). After the polishing surface of the semiconductor substrate in the carrier is arranged in contact with the polishing layer of the polishing pad, the polishing process can be performed by relative rotation under pressure (step 20).

[0073] In the polishing process, slurry flows into the polishing surface (step 21), and the polishing process can be performed by rotating a semiconductor substrate mounted on a carrier relative to the polishing surface while in contact with it. Simultaneously, a polishing layer adjustment process 22 can be performed using a conditioner.

[0074] The adjustment process 22 can be a process to maintain the polishing performance of the polishing layer at a certain level or above. Specifically, the polishing pad includes a polishing layer with a polishing surface, the polishing layer including multiple pores, and the polishing surface including micro-recesses formed by the multiple pores. Processing residues and reaction products in the polishing process may reduce the polishing performance of the micro-recesses. To prevent this reduction in polishing performance, the adjustment process 22 can maintain polishing performance by preventing the micro-recesses from being blocked by processing residues and reaction products.

[0075] However, since the adjustment process 22 is a process of scraping the surface of the polishing layer, simply repeating the adjustment process 22 cannot maintain the polishing performance at the same level as the initial polishing pad.

[0076] That is, during the polishing process, the polishing performance of the polishing pad is kept above a certain level by adjusting process 22. However, the polishing performance of the polishing pad is reduced due to repeated polishing processes. In such cases, the polishing pad with reduced polishing performance can be replaced.

[0077] Whether the polishing pad needs to be replaced can be confirmed by whether the actual polishing process is performed within the target polishing time range (step 30). If the polishing process 22 is performed and the time required for the polishing process 22 remains within the target polishing time range (step 31), the polishing process is performed continuously without replacing the polishing pad. If the time required for the polishing process 22 exceeds the target time range (step 32), the polishing pad is replaced, and the replaced polishing pad cannot be reused.

[0078] Depending on the characteristics of the surface being polished within the semiconductor substrate, the polishing process 22 described above may require different polishing pad usage times, and there may be instances where the polishing pad needs to be replaced more quickly than is used in the polishing process.

[0079] That is, if the number of polishing pads used in the polishing process increases, and consequently the number of polishing pads discarded increases, it will cause environmental pollution problems. Furthermore, since the polishing process is performed continuously, as mentioned above, the polishing process needs to be stopped to replace the polishing pads, which will lead to inefficiencies in the semiconductor device manufacturing process.

[0080] To prevent the above-mentioned problems, the present invention relates to a method for refurbishing a polishing pad, which includes the step of supplying water vapor to the polishing pad.

[0081] Figure 2 This is a flowchart of the polishing process for the refurbishment method using the polishing pad of the present invention. As described above... Figure 1 After installing the polishing pad in the sequence shown (step 10), perform the polishing process (step 20).

[0082] When performing the polishing process, it can be confirmed whether the actual polishing process is carried out within the target polishing time range (step 30). If previously... Figure 1 When the existing polishing process shown in step 30 is included in the target polishing time range, the polishing process is performed (step 31); when it is not included in the target polishing time range, the polishing pad is replaced (step 32).

[0083] However, in this invention, the lifespan of the polishing pad can be increased by supplying water vapor at 50°C to 120°C for 1 to 10 minutes (step 40) without replacing polishing pads not included in the target polishing time range.

[0084] By supplying water vapor to the polishing pad in step 40, the morphology of the micro-recesses on the polished surface formed by the plurality of pores included in the polishing layer can be changed. In one embodiment, according to Formula 1, the rate of change of the surface roughness Sa of the polished surface based on the morphological change of the micro-recesses can be 30% to 70%.

[0085] [Formula 1]

[0086] (Sa r -Sa f ) / Sa f ×100

[0087] in,

[0088] Sa f The surface roughness Sa of the polished surface before water vapor is supplied to the polishing pad.

[0089] Sa r The surface roughness Sa of the polished surface after water vapor is supplied to the polishing pad.

[0090] The three-dimensional arithmetic mean surface roughness Sa is a parameter that extends the surface roughness parameter Ra in three dimensions. It refers to the average of the absolute values ​​of Z(x, y) on the thin film surface. That is, it refers to the arithmetic mean height when the valley regions in three dimensions are transformed into absolute values ​​and become peak values. The surface roughness parameter Sa is the average of the average height differences of the average surface and is one of the most widely used parameters. This parameter is not significantly affected by scratches, contamination, and measurement noise.

[0091] The rate of change of the surface roughness Sa of the polished surface is based on Equation 1, ranging from 30% to 70%, 40% to 69%, and 43% to 68%. Within these ranges, the morphology of the micro-recesses on the polished surface changes due to the supply of water vapor, and the degree of change in the morphology of the micro-recesses may affect the removal rate (RR) and the within-wafer nonuniformity (WIWNU).

[0092] Another three-dimensional surface roughness parameter, Spk, is the average height of the upward-protruding peak at the center of the polished layer, while Svk is the average height of the downward-protruding groove (valley) at the center of the polished layer.

[0093] Spk and Svk are defined using the Abbott curve. Figure 4 The Abbott curve represents the height distribution of surface material. It is a cumulative function of the material fraction of the surface at a specific depth below the highest peak. In other words, the Abbott curve shows that as the depth of the roughness profile increases, the surface material fraction increases. At the highest peak, the material fraction is 0%, while at the deepest point (or "valley"), the material fraction is 100%. The minimum secant slope, i.e., the optimally defined line, divides the Abbott curve into the following three ranges:

[0094] a) Core roughness depth S k [μm] represents the depth of the roughness core profile;

[0095] b) The reduced peak height Spk[μm], i.e., the average height of the peak bulging upwards from the center; and

[0096] c) Reduced groove depth Svk[μm], which is the average depth of the groove protruding downward from the center.

[0097] Polishing performance, such as polishing rate and polishing unevenness, can be affected by the surface roughness of the polished layer. In particular, parameters used to assess changes before and after wear can be Spk and Svk. In the polished layer of a polishing pad, the surface roughness varies due to the polishing process, and changes in surface roughness result in decreased polishing performance. Typically, wear occurs at the highest points of the surface; therefore, to assess the wear condition, it may be important to confirm the degree of change using parameters based on height distribution.

[0098] In one embodiment, the rate of change of Svk of the polished surface, as expressed by Equation 4 below, can be from 0.5% to 50%:

[0099] [Formula 4]

[0100] (Svk r -Svk f ) / Svk f ×100

[0101] in,

[0102] Svk f The surface roughness Svk of the polished surface before water vapor is supplied to the polishing pad.

[0103] Svk r The surface roughness Svk of the polished surface is determined after water vapor is supplied to the polishing pad.

[0104] The rate of change of the surface roughness Svk of the polished surface calculated by Equation 4 can be 0.5% to 50%, 10% to 45%, or 15% to 42%. In the confirmation results of the rate of change of the parameters used to assess the wear condition, the degree of change relative to before the supply of water vapor to the polishing pad can be confirmed, which may mean that the polishing pad can be refurbished by supplying water vapor.

[0105] The polishing pad refurbishment method of the present invention may further include step 41 for adjustment. Specifically, the polishing pad is mounted on a flat plate (step 10), and a polishing process can be performed (step 20). When the polishing process (step 20) is performed, it can be confirmed whether the actual polishing process is performed within the target polishing time range (step 30). In step 30, polishing process 31 is performed when the target polishing time range is included; when the range is not included, the polishing pad is not replaced, but water vapor at 50°C to 120°C is supplied for 1 to 10 minutes (step 40), and the lifespan of the polishing pad is increased by making adjustments (step 41).

[0106] In step 40, water vapor at a temperature of 50°C to 120°C can be supplied for 1 to 10 minutes. The temperature of the water vapor can be 50°C to 120°C, 60°C to 120°C, 70°C to 120°C, 50°C to 110°C, 60°C to 110°C, or 70°C to 110°C. If water vapor is supplied within the temperature range described above, the morphology of the micro-recesses changes, and the surface roughness of the polished surface changes due to this morphological change, thereby improving polishing performance and enabling the refurbishment of the polishing pad. Corrosion of the polishing equipment can be prevented. While water vapor at temperatures up to 120°C can be used for stable maintenance of the polishing equipment, it is not limited to this range. Water vapor that enables the refurbishment of the polishing pad by changing the surface roughness of the polished surface is not limited by a specific temperature range and can be used.

[0107] In the step of supplying the water vapor, the water vapor can be supplied for 1 to 10 minutes, specifically 2 to 8 minutes, 3 to 7 minutes, 4 to 6 minutes, 4 to 8 minutes, or 4 to 10 minutes. When water vapor is supplied within this time range, the surface roughness of the polished surface can be varied, thereby enabling the refurbishment of the polishing pad. Furthermore, by supplying water vapor within this time range, the supply time range of water vapor for refurbishing the polishing pad in the polishing process is optimized, allowing the polishing pad to be refurbished in a shorter time compared to pad replacement, thus optimizing the efficiency of the polishing process.

[0108] The adjustment step 41 changes the surface roughness by scraping the surface of the polishing layer. In the polishing pad refurbishment method of the present invention, the polishing performance of the polishing pad can be improved by step 40 of supplying water vapor to the polishing pad and by the adjustment step 41. By supplying water vapor to the polishing pad to change the morphology of the micro-recesses, and then changing the surface roughness through the adjustment process, the polishing performance can be improved.

[0109] Specifically, the polishing pad includes a polishing layer with a polishing surface, the polishing layer including a plurality of pores, and the polishing surface including micro-recesses formed by the plurality of pores. For example... Figure 5 As shown, the micro-recesses formed on the polished surface cannot be maintained by the polishing process to maintain their concave shape, but can form gentle grooves. The polished surface including the gentle grooves has a low surface roughness, resulting in lower polishing performance, and therefore cannot be used in polishing processes.

[0110] When water vapor is supplied (step 40), the smooth groove can be partially restored to a shape similar to its original state, and by additional adjustment process 41, it can exhibit a surface roughness at the same level as the shape of the fine recess before the polishing process.

[0111] Step 40, supplying water vapor to the polishing pad, can be performed with the polishing pad mounted on a flat plate. Specifically, the polishing pad is mounted on a flat plate for use in a polishing process, and after use in the polishing process, it is confirmed whether the actual polishing process is performed within the target polishing time range (step 30). If it is not within the range, water vapor can be supplied to the polishing pad (step 40), and adjustment 41 can be performed. At this time, the steps of supplying water vapor to the polishing pad (step 40) and the adjustment (step 41) can be performed with the polishing pad mounted on a flat plate.

[0112] That is, in order to refurbish the polishing pad, water vapor is supplied while the polishing pad is mounted on a flat plate (step 40) and adjustments are made (step 41) so that the process required to refurbish the polishing pad can be minimized.

[0113] In another embodiment, step 40, supplying water vapor to the polishing pad, can be performed with the polishing pad removed from the plate. The polishing pad, removed as described above, is cleaned, and water vapor is supplied to it (step 40). The polishing pad, now supplied with water vapor, is mounted on the plate and can be reused after adjustments (step 41).

[0114] Step 40, which involves supplying water vapor to the polishing pad, can be categorized based on whether the polishing pad is attached to a plate. In the method of supplying water vapor (step 40) and adjusting (step 41) while the pad is attached to a plate, the step of removing the polishing pad from the plate can be omitted, simplifying the process and resulting in a relatively higher surface roughness recovery compared to the method described later, which involves removing the pad from the plate and supplying water vapor. This high surface roughness recovery depends on whether water vapor is supplied quickly after the polishing process. This utilizes the property that if the polished surface containing the porous polyurethane polishing layer is deformed by the polishing process and water vapor is supplied, the porous polyurethane will recover to its original shape, thus restoring the surface roughness to a higher level. Conversely, if time passes after the polishing process, the restorative property of the porous polyurethane will decrease, resulting in differences in surface roughness even when water vapor is supplied to the polished surface.

[0115] In contrast to the previous refurbishment method that supplied water vapor while the polishing pad was attached to the plate, the refurbishment method that removes the polishing pad from the plate adds a process for removing the plate. Although the surface roughness after refurbishment is relatively low, the polishing pad separated from the plate can be cleaned separately, and foreign matter generated during the polishing process can be removed. This prevents defects caused by foreign matter from occurring in the polishing process performed after the refurbishment process.

[0116] Subsequently, the polishing pad, with its improved service life, can be used to perform a polishing process. Step 50, used to check whether the polishing pad needs to be replaced, determines whether the refurbished polishing pad has exceeded the target polishing time range. If polishing is performed exceeding the target polishing time range, the polishing pad is discarded (step 52) and can be replaced with a new polishing pad.

[0117] Specifically, the polishing layer of the polishing pad according to the refurbishment method of the present invention is characterized in that the polishing recovery index PRI of Formula 2 can be from 3.10 to 3.80.

[0118] [Equation 2]

[0119]

[0120] in,

[0121] Sa is the value of the three-dimensional arithmetic mean surface roughness according to ISO 25178.

[0122] Spk is a value representing the average height of the peak protruding from the center of the surface of the polished layer.

[0123] Svk is a value representing the average height of the groove protruding downwards from the center of the surface of the polished layer.

[0124] The polishing recovery index (PRI) can be an index that has a significant impact on the degree of variation in surface roughness values, which are related to polishing performance, namely the removal rate (RR) and the within-wafer nonuniformity (WIWNU).

[0125] The PRI value represents the degree of recovery of polishing performance. The numerator is the sum of Spk and Svk, and the denominator is Sa. It is the average of the sum of the average height of the peak protruding from the center of the polished layer and the average height of the groove protruding downwards from the center of the polished layer, divided by the average height difference of the average surface. This numerical value can confirm the uniformity of surface roughness. When the PRI value is within the range of this invention, a high level of polishing performance can be achieved.

[0126] Furthermore, within the scope of this invention, the PRI value is the sum of the average height of the peak protruding from the center of the polished layer and the average height of the groove protruding downwards from the center of the polished layer, which increases due to the supply of water vapor. This means that the fine recesses of the polished surface, whose shape has been altered by the polishing process, are restored to their original shape, and the glazed portion of the polished surface is reduced, allowing it to be reused in the polishing process, thereby improving its service life. The polishing recovery index PRI in Formula 2 can be 3.10 to 3.80, for example, 3.11 to 3.79, for example, 3.11 to 3.78. When the polishing recovery index PRI is within the specified range, the polishing rate of the polished surface is excellent, and it also exhibits excellent effects in terms of polishing unevenness.

[0127] Furthermore, in one embodiment, the value of the polishing pad in the refurbishment method according to the present invention, based on Formula 3, can be from 0.01 to 0.22.

[0128] [Formula 3]

[0129]

[0130] in,

[0131] Sa is the value of the three-dimensional arithmetic mean surface roughness.

[0132] Spk is a value representing the average height of the peak protruding from the center of the polished layer's surface.

[0133] Svk is the value for the average height of the groove protruding downwards from the center of the polished layer's surface.

[0134] In Equation 3, the ratio of the difference between the average height Spk of the peak protruding from the center of the polished layer and the average height of the average surface of the polished layer, and the ratio of the difference between the average height of the groove protruding downward from the center of the polished layer and the average height of the average surface of the polished layer, is calculated. The average roughness of the polished layer and the difference between the peak height and the groove height at the center of the surface are then calculated using this ratio, thereby enabling the prediction of polishing performance.

[0135] The value of Equation 3 can be from 0.01 to 0.22, for example from 0.05 to 0.20, or for example from 0.06 to 0.18. When the value of Equation 3 meets the specified range, a high level of polishing performance can be exhibited by maintaining the surface roughness of the polishing layer within an appropriate range. Therefore, when the value of Equation 3 meets the specified range, the polishing pad can be used additionally by the refurbishment method of the present invention, thereby improving the lifespan of the polishing pad while maintaining excellent polishing performance within the improved lifespan range.

[0136] Furthermore, the shape of the fine recesses on the polished surface changes due to the polishing process, and glazing occurs on a portion of the polished surface, which may reduce the polishing performance of the polishing pad. Therefore, by supplying water vapor to the polishing pad and adjusting it according to the refurbishment method of the present invention, the value obtained by Equation 3 being included within the scope of the present invention means that the fine recesses on the polished surface are restored to their original shape, and the glazed portion of the polished surface is reduced, ultimately restoring the polishing performance.

[0137] The polishing pad used in the refurbishment method of the present invention can be applied to a process in which calcined cerium dioxide slurry is supplied at a rate of 200 mL / min, a semiconductor substrate to be polished is pressurized at a load of 3.5 psi, and the silicon oxide film is polished for 60 seconds at a polishing pad rotation speed of 93 rpm and a semiconductor substrate rotation speed of 87 rpm. The polishing rate can be [missing information]. to The polishing non-uniformity (WIWNU) can be 8% to 9%. Polishing pads within the range of the polishing rate and polishing non-uniformity can have their service life improved using the refurbishment method of the present invention, but are not limited to the polishing pads mentioned above, and polishing pads whose polishing performance has been partially degraded due to the polishing process can have their polishing performance restored using the refurbishment method of the present invention.

[0138] The polishing rate and polishing unevenness are affected by the film quality of the object and the type of slurry. When the polishing process is performed under the conditions described above, the polishing rate is... to The polishing rate is lower than the target polishing rate, which may mean a decrease in polishing efficiency. Furthermore, a polishing unevenness of 8% to 9% may also mean a decrease in polishing performance compared to the target polishing unevenness.

[0139] As described above, polishing pads whose polishing performance has decreased due to polishing rate and polishing unevenness can have their service life extended by spraying water vapor at 50°C to 120°C onto the surface of the polishing layer for 1 to 10 minutes and adjusting it, as previously explained. The temperature of the water vapor can be 50°C to 120°C, 60°C to 120°C, 70°C to 120°C, 50°C to 110°C, 60°C to 110°C, or 70°C to 110°C. Within these ranges, the surface roughness of the polishing layer can be made to achieve a level equivalent to that of a new polishing pad. Using water vapor within these temperature ranges can prevent corrosion of the polishing equipment and enable stable maintenance. However, the use of water vapor within these temperature ranges, which allows for the refurbishment of the polishing pad by changing the surface roughness of the polished surface, is not limited to these temperature ranges and can be used in any range.

[0140] In the step of spraying and adjusting the water vapor, specifically, the polishing process for the polishing object, namely the semiconductor substrate, is completed while the substrate is mounted on a flat plate, and the water vapor can be sprayed and adjusted within the time required to mount the new semiconductor substrate on the carrier.

[0141] The polishing pad can be separated from the plate in another way, and after cleaning with DIW, it can be sprayed with water vapor at 50°C to 120°C for 1 to 10 minutes, then installed on the plate and adjusted before reuse.

[0142] That is, in the refurbishment method, the following methods can be used: continuously spraying water vapor and adjusting it while it is mounted on the plate; and first cleaning the polishing pad separated from the plate, then spraying water vapor, and then mounting it on the plate and adjusting it.

[0143] As described above, the lifespan of the polishing pad can be increased whether it is mounted on a flat plate or detached from a flat plate. The polishing pad's lifespan can be extended by applying the refurbishment method of the present invention when any one or more of the following conditions are met.

[0144] i) Polishing pads used in the polishing process

[0145] ii) The surface roughness Sa of the polished surface is less than 6 μm.

[0146] iii) The surface roughness Spk of the polished surface is below 5 μm.

[0147] iv) The surface roughness Svk of the polished surface is below 16 μm.

[0148] The polishing pad used in the i) polishing process can specifically mean: in a process where calcined cerium dioxide slurry is supplied at a rate of 200 mL / min, and the semiconductor substrate to be polished is subjected to a load of 3.5 psi, the polishing pad rotates at 93 rpm, the semiconductor substrate rotates at 87 rpm, and the silicon oxide film is polished for 60 seconds, the polishing rate is... to The polishing nonuniformity (WIWNU) is 8% to 9%, as mentioned above, which reduces polishing efficiency due to a low polishing rate or polishing performance due to low polishing nonuniformity. However, polishing pads with reduced polishing performance are not limited to the aforementioned polishing pads and can be used without any restriction.

[0149] Furthermore, for the process of separating from the plate and spraying water vapor and making adjustments, compared to performing subsequent processes while the plate is mounted on the plate, additional time is required to separate from and reinstall the plate. However, the step of cleaning with DIW is beneficial in terms of removing impurities adhering to the surface of the polished layer during the polishing process.

[0150] The adjustment is a step of adjusting the surface of the polished layer with a rotational speed of 20 rpm to 150 rpm, a load of 1 lb to 90 lb, and a sweep rate of 1 to 25 sweep rates, but is not limited to the range described above; adjustment conditions that enable the polishing performance to be achieved after spraying water vapor can be applied.

[0151] In a process of polishing a silicon oxide film by spraying water vapor and adjusting a polishing pad using the refurbishment method described in this invention, calcined cerium dioxide slurry is supplied at a rate of 200 mL / min, a semiconductor substrate to be polished is pressurized at a load of 3.5 psi, the polishing pad rotates at 93 rpm, the semiconductor substrate rotates at 87 rpm, and the polishing rate is achieved in 60 seconds. to to to Furthermore, the polishing non-uniformity (WIWNU) can be 3% to 7%, 4% to 7%, or 4.1% to 6.8%. As described above, the polishing pad improves the polishing rate by spraying water vapor and making adjustments, and excellent results can also be confirmed in terms of polishing non-uniformity.

[0152] In one embodiment of the present invention, the polishing layer of the polishing pad may include a polishing layer formed from a cured material comprising a composition comprising a urethane-based prepolymer, a curing agent, and a foaming agent.

[0153] Each component contained in the composition will be described in detail below.

[0154] "Prepolymer" means a low molecular weight polymer that has had its polymerization stopped at an intermediate stage during the manufacturing process of a cured product, making it easier to mold. Prepolymers can be molded into cured products alone or after reacting with other polymeric compounds.

[0155] In one embodiment, the urethane-based prepolymer can be prepared by reacting an isocyanate compound with a polyol.

[0156] The isocyanate compound used in the preparation of the urethane-based prepolymer may be selected from the group consisting of aromatic diisocyanates, aliphatic diisocyanates, alicyclic diisocyanates, and combinations thereof.

[0157] For example, the isocyanate compound may comprise one selected from the group consisting of 2,4-toluenediisocyanate (2,4-TDI), 2,6-toluenediisocyanate (2,6-TDI), naphthalene-1,5-diisocyanate, p-phenylene diisocyanate, toluidine diisocyanate, 4,4'-diphenylmethane diisocyanate, hexamethylene diisocyanate, dicyclohexylmethane diisocyanate, isophorone diisocyanate, and combinations thereof.

[0158] "Polyol" refers to a compound in which each molecule comprises at least two hydroxyl groups (-OH). Such polyols may include, for example, one of the group consisting of polyether polyols, polyester polyols, polycarbonate polyols, acrylic polyols, and combinations thereof.

[0159] For example, the polyol may comprise one selected from the group consisting of polytetramethylene ether glycol, polypropylene ether glycol, ethylene glycol, 1,2-propanediol, 1,3-propanediol, 1,2-butanediol, 1,3-butanediol, 2-methyl-1,3-propanediol, 1,4-butanediol, neopentyl glycol, 1,5-pentanediol, 3-methyl-1,5-pentanediol, 1,6-hexanediol, diethylene glycol, dipropylene glycol, tripropylene glycol, and combinations thereof.

[0160] The polyol may have a weight-average molecular weight (Mw) of about 100 g / mol to about 3000 g / mol. The polyol may have, for example, a weight-average molecular weight (Mw) of about 100 g / mol to about 3000 g / mol, about 100 g / mol to about 2000 g / mol, or about 100 g / mol to about 1800 g / mol.

[0161] In one embodiment, the polyol may comprise: a low molecular weight polyol with a weight-average molecular weight (Mw) of about 100 g / mol or more and about 300 g / mol or less; and a high molecular weight polyol with a weight-average molecular weight (Mw) of about 300 g / mol or more and about 1800 g / mol or less.

[0162] The urethane-based prepolymer may have a weight-average molecular weight (Mw) of about 500 g / mol to about 3000 g / mol. The urethane-based prepolymer may have a weight-average molecular weight (Mw) of, for example, about 600 g / mol to about 2000 g / mol, or, for example, about 800 g / mol to about 1000 g / mol.

[0163] In one embodiment, the isocyanate compound used to prepare the urethane-based prepolymer may comprise an aromatic diisocyanate compound, such as 2,4-toluene diisocyanate (2,4-TDI) and 2,6-toluene diisocyanate (2,6-TDI). The polyol compound used to prepare the urethane-based prepolymer may comprise polytetramethylene ether glycol (PTMEG) and diethylene glycol (DEG).

[0164] In another embodiment, the isocyanate compound used to prepare the urethane-based prepolymer may comprise an aromatic diisocyanate compound and an alicyclic diisocyanate compound. For example, the aromatic diisocyanate compound may comprise 2,4-toluene diisocyanate (2,4-TDI) and 2,6-toluene diisocyanate (2,6-TDI), and the alicyclic diisocyanate compound may comprise dicyclohexylmethane diisocyanate (H... 12 MDI). The polyol compound used to prepare the urethane-based prepolymer may include polytetramethylene ether glycol (PTMEG) and diethylene glycol (DEG).

[0165] The isocyanate end group content (NCO%) of the urethane-based prepolymer can be from about 5 wt% to about 11 wt%, for example from about 5 wt% to about 10 wt%, for example from about 5 wt% to about 8 wt%, for example from about 8 wt% to about 10 wt%. When the NCO% is within the range described above, the physical properties of the polished layer are exhibited within a suitable polishing pad, the desired polishing performance can be maintained in the polishing process, and defects that may be generated on the wafer during the polishing process can be minimized.

[0166] Furthermore, by adjusting the polishing selectivity (Ox ​​RR / NtRR) of the oxide and nitride films, dishing, recess, and erosion can be prevented, and surface planarization within the wafer can be achieved.

[0167] The isocyanate end group content (NCO%) of the urethane-based prepolymer can be designed by comprehensively adjusting the types and contents of isocyanate compounds and polyol compounds used to prepare the urethane-based prepolymer, as well as the process conditions such as temperature, pressure, and time used to prepare the urethane-based prepolymer, and the types and contents of additives used to prepare the urethane-based prepolymer.

[0168] The curing agent is a compound used to chemically react with the urethane-based prepolymer to form a final cured structure within the polished layer. For example, it may contain an amine compound or an alcohol compound. Specifically, the curing agent may contain one selected from the group consisting of aromatic amines, aliphatic amines, aromatic alcohols, fatty alcohols, and combinations thereof.

[0169] For example, the curing agent may comprise a compound selected from 4,4'-methylenebis(2-chloroaniline) (MOCA), diethyltoluenediamine (DETDA), diaminodiphenylmethane, dimethylthio-toluene diamine (DMTDA), propanediol bis p-aminobenzoate, and methyl methylenebis-o-aminobenzoate. One of the group consisting of bis-methylanthranilate, diaminodiphenylsulfone, m-xylylenediamine, isophoronediamine, ethylenediamine, diethylenetriamine, triethylenetetramine, polypropylenediamine, polypropylenetriamine, bis(4-amino-3-chlorophenyl)methane, and combinations thereof.

[0170] Based on 100 parts by weight of the urethane prepolymer, the content of the curing agent can be from about 18 parts by weight to about 27 parts by weight, for example, from about 19 parts by weight to about 26 parts by weight, for example, from about 20 parts by weight to about 26 parts by weight. When the content of the curing agent meets the range, it is more conducive to achieving the desired performance of the polishing pad.

[0171] As a component contributing to the porous structure within the polished layer, the foaming agent may comprise one selected from the group consisting of solid foaming agents, gaseous foaming agents, liquid foaming agents, and combinations thereof. In one embodiment, the foaming agent may include a solid foaming agent, a gaseous foaming agent, or a combination thereof.

[0172] The average particle size of the solid foaming agent can be from about 5 μm to about 200 μm, for example from about 20 μm to about 50 μm, for example from about 21 μm to about 50 μm, for example from about 25 μm to about 45 μm. When the solid foaming agent is thermally expanded particles as described below, the average particle size of the solid foaming agent can refer to the average particle size of the thermally expanded particles themselves. When the solid foaming agent is unexpanded particles as described later, the average particle size of the solid foaming agent can refer to the average particle size of the particles after they have expanded due to heat or pressure.

[0173] The solid foaming agent may contain expandable particles. These expandable particles, which are particles that can expand under heat or pressure, have a final size in the polished layer that depends on the heat or pressure applied during the preparation of the polished layer. The expandable particles may include thermally expanded particles, unexpanded particles, or a combination thereof. Thermally expanded particles, as particles pre-expanded by heat, refer to particles whose size changes little or almost nothing due to the heat or pressure applied during the preparation of the polished layer. Unexpanded particles, as particles that have not pre-expanded, refer to particles that expand under heat or pressure during the preparation of the polished layer and whose final size is determined.

[0174] The expandable particles may include: a resin outer skin; and expansion-inducing components present inside the outer skin.

[0175] For example, the outer skin may comprise a thermoplastic resin, which may be one or more selected from the group consisting of vinylidene chloride copolymers, acrylonitrile copolymers, methacrylonitrile copolymers, and acrylic copolymers.

[0176] The swelling-inducing component may include one selected from the group consisting of hydrocarbon compounds, chlorofluorocarbons, tetraalkylsilane compounds, and combinations thereof.

[0177] Specifically, the hydrocarbon compound may comprise one selected from the group consisting of ethane, ethylene, propane, propylene, n-butane, isobutene, n-butene, isobutene, n-pentane, isopentane, n-hexane, heptane, petroleum ether, and combinations thereof.

[0178] The fluorochloro compound may include one selected from the group consisting of trichlorofluoromethane (CCl3F), dichlorodifluoromethane (CCl2F2), chlorotrifluoromethane (CClF3), dichlorotetrafluoroethane (CClF2-CClF2), and combinations thereof.

[0179] The tetraalkylsilane compound may include one selected from the group consisting of tetramethylsilane, trimethylethylsilane, trimethylisopropylsilane, trimethyl-n-propylsilane, and combinations thereof.

[0180] The solid foaming agent may optionally contain inorganically treated particles. For example, the solid foaming agent may contain expandable particles treated with inorganic components. The solid foaming agent may contain expandable particles treated with silica (SiO2) particles. The inorganic component treatment of the solid foaming agent can prevent the aggregation of multiple particles. The chemical, electrical, and / or physical properties of the foaming agent surface of the inorganically treated solid foaming agent may differ from those of the untreated solid foaming agent.

[0181] Based on 100 parts by weight of the urethane prepolymer, the content of the solid foaming agent may be from about 0.5 parts by weight to about 10 parts by weight, for example from about 1 part by weight to about 3 parts by weight, for example from about 1.3 parts by weight to about 2.7 parts by weight, for example from about 1.3 parts by weight to about 2.6 parts by weight.

[0182] The type and content of the solid foaming agent can be designed according to the desired pore structure and physical properties of the polished layer.

[0183] The gaseous foaming agent may include an inert gas. The gaseous foaming agent may be added during the reaction of the second urethane prepolymer with the curing agent, thereby serving as a pore-forming element.

[0184] There are no particular limitations on the type of inert gas, as long as it is a gas that does not participate in the reaction between the second urethane prepolymer and the curing agent. For example, the inert gas may include one selected from the group consisting of nitrogen (N2), argon (Ar), helium (He), and combinations thereof. Specifically, the inert gas may contain nitrogen (N2) or argon (Ar).

[0185] The type and content of the gas foaming agent can be designed according to the desired pore structure and physical properties of the polished layer.

[0186] In one embodiment, the foaming agent may include a solid foaming agent. For example, the foaming agent may be formed solely from a solid foaming agent.

[0187] The solid foaming agent may contain expandable particles, which may include thermally expandable particles. For example, the solid foaming agent may consist only of thermally expandable particles. While the variability of the pore structure decreases when it is composed only of thermally expandable particles and does not contain the unexpanded particles, predictability increases, thus facilitating the achievement of uniform pore characteristics across all areas of the polished layer.

[0188] In one embodiment, the thermally expanded particles can be particles having an average particle size of about 5 μm to about 200 μm. The average particle size of the thermally expanded particles can be about 5 μm to about 100 μm, for example, about 10 μm to about 80 μm, for example, about 20 μm to about 70 μm, for example, about 20 μm to about 50 μm, for example, about 30 μm to about 70 μm, for example, about 25 μm to 45 μm, for example, about 40 μm to about 70 μm, for example, about 40 μm to about 60 μm. The average particle size is defined as the D50 of the thermally expanded particles.

[0189] In one embodiment, the density of the thermally expanded particles can be approximately 30 kg / m³. 3 Approximately 80 kg / m 3 For example, approximately 35 kg / m 3 Approximately 80 kg / m 3 For example, approximately 35 kg / m 3 Approximately 75 kg / m 3 For example, approximately 38 kg / m3 Approximately 72kg / m 3 For example, approximately 40 kg / m 3 Approximately 75 kg / m 3 For example, approximately 40 kg / m 3 Approximately 72kg / m 3 .

[0190] In one embodiment, the foaming agent may include a gaseous foaming agent. For example, the foaming agent may include both solid and gaseous foaming agents. Matters relating to the solid foaming agent are as described above.

[0191] The gaseous foaming agent may include nitrogen.

[0192] The gaseous blowing agent can be injected using a prescribed injection line during the mixing of the second urethane prepolymer, the solid blowing agent, and the curing agent. The injection rate of the gaseous blowing agent can be approximately 0.8 L / min to approximately 2.0 L / min, for example, approximately 0.8 L / min to approximately 1.8 L / min, for example, approximately 0.8 L / min to approximately 1.7 L / min, for example, approximately 1.0 L / min to approximately 2.0 L / min, for example, approximately 1.0 L / min to approximately 1.8 L / min, for example, approximately 1.0 L / min to approximately 1.7 L / min.

[0193] The composition used to prepare the polished layer may also contain other additives such as surfactants and reaction rate modifiers. The names "surfactant," "reaction rate modifier," etc., are arbitrary names based on the main function of the substance, and each corresponding substance does not necessarily perform only the function limited by the corresponding name.

[0194] There are no particular limitations on the surfactant, as long as it is a substance that prevents the aggregation or overlapping of pores. For example, the surfactant may include silicone-based surfactants.

[0195] Based on 100 parts by weight of the second urethane prepolymer, the amount of surfactant can be from about 0.05 parts by weight to about 2 parts by weight. Specifically, based on 100 parts by weight of the second urethane prepolymer, the content of the surfactant can be from about 0.2 parts by weight to about 1.9 parts by weight, for example from about 0.2 parts by weight to about 1.8 parts by weight, for example from about 0.2 parts by weight to about 1.7 parts by weight, for example from about 0.2 parts by weight to about 1.6 parts by weight, for example from about 0.2 parts by weight to about 1.5 parts by weight, for example from about 0.5 parts by weight to 1.5 parts by weight. When the surfactant content is within the said range, the pores caused by the gas blowing agent can be stably formed and maintained within the mold.

[0196] The reaction rate regulator, acting as a regulator to promote or delay the reaction, may be a reaction promoter, a reaction delayer, or both, depending on the purpose. The reaction rate regulator may contain a reaction promoter. For example, the reaction promoter may be one or more reaction promoters selected from the group consisting of tertiary amine compounds and organometallic compounds.

[0197] Specifically, the reaction rate regulator may comprise a mixture selected from triethylenediamine, dimethylethanolamine, tetramethylbutyldiamine, 2-methyl-triethylenediamine, dimethylcyclohexylamine, triethylamine, triisopropanolamine, 1,4-diazabicyclo(2,2,2)octane, bis(2-methylaminoethyl) ether, trimethylaminoethylethanolamine, N,N,N,N,N”-pentamethyldiethylenetriamine, dimethylaminoethylamine, dimethylaminopropylamine, benzyldimethylamine, N-ethylmorpholine, N,N-dimethylaminoethylmorpholine, N,N-dimethylcyclohexylamine, 2-methyl-2-azanorbornene, dibutyltin dilaurate, stannous octoate, dibutyltin diacetate, dioctyltin diacetate, dibutyltin maleate, dibutyltin di-2-ethylhexanoate, and dibutyltin dithiol. The reaction rate regulator may comprise one or more of the group consisting of benzyl dimethylamine, N,N-dimethylcyclohexylamine, and triethylamine.

[0198] Based on 100 parts by weight of the urethane-based prepolymer, the amount of the reaction rate regulator can be from about 0.05 parts by weight to about 2 parts by weight. Specifically, based on 100 parts by weight of the urethane-based prepolymer, the amount of the reaction rate regulator can be from about 0.05 parts by weight to about 1.8 parts by weight, for example from about 0.05 parts by weight to about 1.7 parts by weight, for example from about 0.05 parts by weight to about 1.6 parts by weight, for example from about 0.1 parts by weight to about 1.5 parts by weight, for example from about 0.1 parts by weight to about 0.3 parts by weight, for example from about 0.2 parts by weight to about 1.8 parts by weight, for example from about 0.2 parts by weight to about 1.7 parts by weight, for example from about 0.2 parts by weight to about 1.6 parts by weight, for example from about 0.2 parts by weight to about 1.5 parts by weight, for example from about 0.5 parts by weight to about 1 part by weight. When the reaction rate regulator is used within the above-mentioned content range, a polished layer with the desired pore size and hardness can be formed by appropriately adjusting the curing reaction rate of the prepolymer composition.

[0199] When the polishing pad includes a buffer layer, the buffer layer serves to support the polishing layer and absorb and disperse external impacts applied to the polishing layer, thereby minimizing damage to the polished object and the occurrence of defects in the polishing process using the polishing pad.

[0200] The cushioning layer may contain non-woven fabric or suede, but is not limited to these.

[0201] In one embodiment, the buffer layer may be a resin-impregnated nonwoven fabric. The nonwoven fabric may comprise one selected from the group consisting of polyester fibers, polyamide fibers, polypropylene fibers, polyethylene fibers, and combinations thereof.

[0202] The resin impregnated in the nonwoven fabric may comprise one selected from the group consisting of polyurethane resin, polybutadiene resin, styrene-butadiene copolymer resin, styrene-butadiene-styrene copolymer resin, acrylonitrile-butadiene copolymer resin, styrene-ethylene-butadiene-styrene copolymer resin, silicone rubber resin, polyester elastomer resin, polyamide elastomer resin, and combinations thereof.

[0203] The method for preparing the polishing pad is described in detail below.

[0204] In another embodiment of the present invention, a method for preparing a polishing pad may be provided, the method comprising: a step of preparing a prepolymer composition; a step of preparing a polishing layer preparation composition comprising the prepolymer composition, a foaming agent and a curing agent; and a step of preparing a polishing layer by curing the polishing layer preparation composition.

[0205] The preparation of the prepolymer composition may be a process for preparing urethane prepolymers by reacting a diisocyanate compound with a polyol compound. The matters concerning the diisocyanate compound and the polyol compound are the same as those described above regarding the polishing pad.

[0206] The isocyanate group (NCO group) content of the prepolymer composition may be from about 5 wt% to about 15 wt%, for example from about 5 wt% to about 8 wt%, for example from about 5 wt% to about 7 wt%, for example from about 8 wt% to about 15 wt%, for example from about 8 wt% to about 14 wt%, for example from about 8 wt% to about 12 wt%, for example from about 8 wt% to about 10 wt%.

[0207] The isocyanate group content of the prepolymer composition may originate from the terminal isocyanate groups of the urethane prepolymer, unreacted isocyanate groups in the diisocyanate compound, etc.

[0208] The viscosity of the prepolymer composition at about 80°C can be from about 100 cps to about 1000 cps, for example from about 200 cps to about 800 cps, for example from about 200 cps to about 600 cps, for example from about 200 cps to about 550 cps, for example from about 300 cps to about 500 cps.

[0209] The foaming agent may include a solid foaming agent or a gaseous foaming agent.

[0210] When the foaming agent includes a solid foaming agent, the steps for preparing the composition for preparing the polishing layer may include: preparing a first preliminary composition by mixing the prepolymer composition with the solid foaming agent; and preparing a second preliminary composition by mixing the first preliminary composition with a curing agent.

[0211] The viscosity of the first preparative composition at about 80°C can be about 1000 cps to about 2000 cps, for example about 1000 cps to about 1800 cps, for example about 1000 cps to about 1600 cps, for example about 1000 cps to about 1500 cps.

[0212] When the foaming agent includes a gaseous foaming agent, the steps for preparing the composition for preparing the polishing layer may include: preparing a third preliminary composition comprising the prepolymer composition and the curing agent; and preparing a fourth preliminary composition by injecting the gaseous foaming agent into the third preliminary composition.

[0213] In one embodiment, the third preparative composition may further comprise a solid foaming agent.

[0214] In one embodiment, the process for preparing the polished layer may include: preparing a mold preheated to a first temperature; injecting and curing the polished layer preparation composition into the preheated mold; and post-curing the cured polished layer preparation composition at a second temperature higher than the preheating temperature.

[0215] In one embodiment, the first temperature can be about 50 to about 150°C, for example about 90 to about 140°C, and more preferably about 9°C to about 120°C.

[0216] In one embodiment, the second temperature can be from about 100°C to about 130°C, for example, from about 100°C to 125°C, for example, from about 100°C to about 120°C.

[0217] The step of curing the polishing preparation composition at the first temperature can be performed for about 5 minutes to about 60 minutes, for example about 5 minutes to about 40 minutes, for example about 5 minutes to about 30 minutes, for example about 5 minutes to about 25 minutes.

[0218] At the second temperature, the post-curing step of the polishing layer preparation composition that has been cured at the first temperature can be performed for about 5 hours to about 30 hours, for example about 5 hours to about 25 hours, for example about 10 hours to about 30 hours, for example about 10 hours to about 25 hours, for example about 12 hours to about 24 hours, for example about 15 hours to about 24 hours.

[0219] The method for preparing the polishing pad may include the step of processing at least one side of the polishing layer.

[0220] As another embodiment, the step of processing at least one surface of the polished layer may include at least one of the following steps: a first step of forming a groove on at least one surface of the polished layer; a second step of performing line turning on at least one surface of the polished layer; and a third step of roughening at least one surface of the polished layer.

[0221] In the first step, the groove may include at least one of the following: concentric circular grooves formed at predetermined intervals from the center of the polished layer; and radial grooves that are continuously connected from the center of the polished layer to the edge of the polished layer.

[0222] In the second step, the line turning process can be performed by using a cutting tool to cut the polished layer to a specified thickness.

[0223] In the third step, the roughening process can be performed by using a sanding roller to process the surface of the polished layer.

[0224] The method for preparing the polishing pad may further include the step of stacking a buffer layer on the opposite side of the polishing surface of the polishing layer.

[0225] The polishing layer and the buffer layer can be laminated using a hot melt adhesive as a medium.

[0226] The hot melt adhesive is applied to the opposite side of the polished surface of the polished layer, and the hot melt adhesive is also applied to the surface of the buffer layer that is in contact with the polished layer. The polished layer and the buffer layer are then stacked so that the surfaces coated with the hot melt adhesive are in contact. The two layers can then be bonded together using a pressure roller.

[0227] In another embodiment, a method for manufacturing a semiconductor element is provided, comprising: attaching a polishing pad, including a polishing surface and a flat plate attachment surface opposite to the polishing surface, to a flat plate; polishing the polishing object by setting the polished surface of the polishing object to contact the polishing surface and simultaneously rotating the polishing pad and the polishing object relative to each other under pressure, wherein the polishing step may include: confirming whether an actual polishing process is performed within a target polishing time range; and, if the execution time of the actual polishing process is not within the target polishing time range, spraying water vapor at 50°C to 120°C onto the surface of the polishing layer of the polishing pad and making adjustments.

[0228] Regarding the step of confirming whether to perform the actual polishing process, if the time required for the polishing process on the object being polished is within the target polishing time range, the object can be replaced and the polishing process can be repeated. However, polishing pads that do not reach the target polishing time range can have their lifespan improved by spraying water vapor and making adjustments. After spraying the water vapor and making adjustments, the polishing recovery index PRI of the polishing layer of the polishing pad based on Formula 2 can be between 3.10 and 3.80.

[0229] [Equation 2]

[0230]

[0231] in,

[0232] Sa is the value of the three-dimensional arithmetic mean surface roughness.

[0233] Spk is a value representing the average height of the peak protruding from the center of the polished layer's surface.

[0234] Svk is the average height of the groove protruding downwards from the center of the polished layer's surface.

[0235] Figures 6A-6D and Figure 7 This is a schematic process diagram of a semiconductor device manufacturing process based on an implementation example. (Refer to...) Figures 6A-6D After mounting the polishing pad 100 according to the described embodiment on the flat plate 200, a semiconductor substrate 500, which is to be polished, is placed on the polishing pad 100. At this time, the surface of the semiconductor substrate 500 to be polished and the polishing surface of the polishing pad 100 are in direct contact. For polishing, polishing slurry 310 is sprayed onto the polishing pad through the nozzle portion 300. The flow rate of the polishing slurry 310 supplied through the nozzle portion 300 can be approximately 10 cm³. 3 / min to approximately 1000cm 3 The range of / min is selected based on the purpose; for example, it could be approximately 50cm.3 / min to approximately 500cm 3 / min, but not limited to this.

[0236] Subsequently, the semiconductor substrate 500 and the polishing pad 100 rotate relative to each other, thereby enabling the surface of the semiconductor substrate 500 to be polished. At this time, the rotation direction of the semiconductor substrate 500 and the rotation direction of the polishing pad 100 can be the same or opposite. The rotation speed of the semiconductor substrate 500 and the polishing pad 100 can be selected according to the purpose, ranging from about 10 rpm to about 500 rpm, for example, from about 30 rpm to about 200 rpm, but not limited thereto.

[0237] When the semiconductor substrate 500 is mounted to the polishing head, it is pressed against the polishing surface of the polishing pad 100 under a specified load, thereby bringing the surface of the semiconductor substrate 500 to be polished into contact with the polishing surface, and then polishing its surface. The load applied to the polishing surface of the polishing pad 100 by the polishing head on the surface of the semiconductor substrate 500 can be approximately 1 gf / cm². 2 Approximately 1000 gf / cm 2 The selection is made within a range depending on the purpose; for example, it could be approximately 10 gf / cm. 2 Approximately 800 gf / cm 2 However, it is not limited to this.

[0238] In one embodiment, in order to keep the polished surface of the polishing pad 100 in a state suitable for polishing, the method for preparing the semiconductor element may further include the step of processing the polished surface of the polishing pad 110 by means of an adjuster 600 while polishing the semiconductor substrate 500.

[0239] Figures 6A to 6D This is a diagram relating to a method for manufacturing a semiconductor element according to an embodiment of the present invention, specifically, Figure 6A This illustrates step a of mounting the polishing pad 100 on the flat plate 200. Figure 6BThe illustration shows step b, in which slurry 310 is injected through nozzle 300 and the polishing process is performed while the semiconductor substrate 500 is in contact with the polishing pad 100. Next, step c, as described above, involves spraying water vapor 710 through a water vapor jetting section 700 onto the polishing pad 100, where the required time for the polishing process targeting the object being polished is not within the target polishing time range, in a step confirming whether to perform the actual polishing process. Specifically, in step c, a water vapor jetting section 700 in the form shown in the accompanying drawings can be used, but it is not limited to this example; any jetting section 700 capable of uniformly spraying water vapor at 50°C to 110°C onto the polishing layer of the polishing pad can be used without limitation.

[0240] Following step c, step d is the adjustment step performed by adjuster 600. Through steps c and d, the polishing performance of the polishing pad 100 on the semiconductor substrate 500 can be restored to a level usable in the polishing process, thus improving the lifespan of the polishing pad 100.

[0241] According to another embodiment of the present invention, a semiconductor element manufacturing apparatus may include: a plate 200 for mounting a polishing pad 100; a carrier 400 for mounting a semiconductor substrate 500; and a water vapor injection unit 700, which can supply water vapor to the polishing pad 100 mounted on the plate 200.

[0242] In addition to the plate 200, carrier 400, and steam jetting unit 700, the semiconductor element manufacturing apparatus may also include a nozzle unit 300, an adjuster 600, etc. The semiconductor element manufacturing apparatus is an apparatus for manufacturing semiconductor elements and may be characterized by including the steam jetting unit 700.

[0243] The water vapor jet section 700 is structured to supply water vapor 710 to the polishing pad 100. More specifically, the polishing performance of the polishing pad 100 can be restored by supplying water vapor 710 to the polishing surface of the polishing pad 100.

[0244] The water vapor injection unit 700 can be used both when the polishing pad 100 is mounted on the plate 200 and when the polishing pad 100 is removed from the plate 200. The water vapor injection unit 700 can be in the form of supplying heated water vapor 710 from the outside and supplying it through the water vapor injection unit 700, or in the form of heating water internally to form water vapor 710 and supplying it when water is supplied to the water vapor injection unit 700. However, it is not limited to the above examples. Any method that can supply water vapor 710 to the polishing pad 100 can be applied.

[0245] In addition, the plate 200, carrier 400, nozzle 300 and adjuster 600 are the same as those used in ordinary semiconductor device manufacturing apparatus and are not subject to structural limitations.

[0246] Specific embodiments of the present invention are given below. However, the embodiments described below are only for specific illustration or description of the present invention and are not intended to limit the present invention.

[0247] Preparation example: Preparation of polishing pads

[0248] A diisocyanate component and a polyol component were mixed and placed in a four-necked flask, then reacted at 80°C to prepare a preliminary composition containing a urethane prepolymer. The reaction proceeded until the isocyanate group content (NCO%) in the preliminary composition reached 9% by weight. Aromatic and alicyclic diisocyanates were used as the diisocyanate component; 2,4-TDI and 2,6-TDI were used as the aromatic diisocyanate, and H2O was used as the alicyclic diisocyanate. 12 MDI. Based on 100 parts by weight of the 2,4-TDI, 25 parts by weight of the 2,6-TDI were used; based on a total of 100 parts by weight of the aromatic diisocyanate, 11 parts by weight of the H were used. 12 MDI. PTMG and DEG were used as the polyol components, with 129 parts by weight of PTMG and 14 parts by weight of DEG used based on a total of 100 parts by weight of the diisocyanate components. 4,4'-methylenebis(2-chloroaniline) (MOCA) was used as a curing agent and mixed such that the molar ratio of amino groups (NH2) in the curing agent to isocyanate groups (NCO groups) in the preparative composition was 0.96. Next, 1.0 part by weight of a solid blowing agent (Akzonobel) was mixed in based on 100 parts by weight of the preparative composition. The preparative composition was injected at a discharge rate of 10 kg / min into a mold preheated to 90°C, with dimensions of 1000 mm wide, 1000 mm long, and 3 mm high, while nitrogen (N2) as a gaseous blowing agent was injected into the mold at a discharge rate of 1.0 L / min. Next, the preparative composition was post-cured at 110°C, and then grooves were formed and turned to prepare a polished layer with a thickness of 20 mm.

[0249] A 10 mm thick buffer layer was prepared, consisting of a polyester resin nonwoven fabric impregnated with urethane resin. A heat-sealable adhesive was coated on one surface of the polished layer, and a heat-sealant was also coated on the other surface of the buffer layer. A pressure roller was then used to bring the adhesive-coated surfaces into contact with each other. Next, a pressure-sensitive adhesive was coated and dried on the other surface of the buffer layer, thereby preparing an adhesive layer for attachment to a flat plate.

[0250] Examples 1 to 8

[0251] After repeatedly performing the polishing process using the polishing pad, polishing pads whose actual polishing time exceeds the target polishing time range are applied to Examples 1 to 8.

[0252] In Examples 1 to 4, after the used polishing pad was separated from the plate, it was cleaned with DIW for 1 minute, then water vapor was sprayed onto the surface of the polishing layer for adjustment, and then it was reattached to the plate (Ex situ).

[0253] In Examples 5 to 8, water vapor was sprayed onto the surface of the polished layer while it was mounted on a flat plate, and adjustments were made (In situ).

[0254] Comparative Example 1

[0255] The new polishing pad prepared in the preparation example is applied in the polishing process.

[0256] Comparative Example 2

[0257] After repeatedly performing the polishing process using the polishing pad, a polishing pad whose actual polishing time exceeded the target polishing time range was used.

[0258] Experimental Example 1: Measurement of Surface Roughness and 3D Images

[0259] Before and after the polishing process, the surface roughness of the polished layer against the polishing pad was measured using a non-contact 3D optical profiler (Bruker, Contour GT).

[0260] Based on the value of Comparative Example 2, the rate of change (%) of the surface roughness Sa of the polished surface before and after the supply of water vapor was calculated by Equation 1 below.

[0261] [Formula 1]

[0262] (Sa r -Saf ) / Sa f ×100

[0263] in,

[0264] Sa f The surface roughness Sa of the polished surface before water vapor is supplied to the polishing pad.

[0265] Sa r The surface roughness Sa of the polished surface after water vapor is supplied to the polishing pad.

[0266] The rate of change (%) of Svk is calculated using Equation 4 below.

[0267] [Formula 4]

[0268] (Svk r -Svk f ) / Svk f ×100

[0269] in,

[0270] Svk f The surface roughness Svk of the polished surface before water vapor is supplied to the polishing pad.

[0271] Svk r The surface roughness Svk of the polished surface is determined after water vapor is supplied to the polishing pad.

[0272] Based on the surface roughness measurement results, the values ​​of Equations 2 and 3 were derived.

[0273] [Equation 2]

[0274]

[0275] [Formula 3]

[0276]

[0277] in,

[0278] Sa is the value of the three-dimensional arithmetic mean surface roughness.

[0279] Spk is a value representing the average height of the peak protruding from the center of the polished layer's surface.

[0280] Svk is the value for the average height of the groove protruding downwards from the center of the polished layer's surface.

[0281] Experiment Example 2: Measurement of SEM Images

[0282] SEM images of the polished layer on the polishing pad were taken before and after the polishing process. The surface was magnified 100x and the SEM images were measured.

[0283] Experimental Example 3: Evaluation of Polishing Performance

[0284] A polishing pad was attached to a CMP apparatus, and the oxide layer of the silicon wafer (PETEOS) was positioned as the polishing surface facing the polishing pad. Calcined cerium dioxide slurry was supplied to the polishing pad at a rate of 200 mL / min, and the oxide film was polished for 60 seconds under the conditions of a carrier load of 3.5 psi, a head speed of 87 rpm, and a plate rotation speed of 93 rpm.

[0285] After polishing, the silicon wafer was removed from the carrier, mounted on a spin dryer, and washed with distilled water (DIW), followed by drying with nitrogen for 15 seconds. The change in film thickness of the dried silicon wafer before and after polishing was measured using an optical interferometric thickness measurement device (manufacturer: Kyence, model: SI-F80R). The polishing rate was then calculated using the following mathematical formula 1.

[0286] [Mathematical Expression 1]

[0287] Polishing rate = Polishing thickness of silicon wafer Polishing time (60 seconds)

[0288] The polishing rate was measured by measuring the thickness of the wafer before and after the polishing process, specifically at 48 to 100 points along a straight line on the wafer. All areas within the cross-section except for those between 1 mm and 3 mm were considered as measured values. These measured values ​​were parameterized, and the average of the measured values ​​was taken as the removal rate (RR). ), and calculated WIWNU (Within Wafer Nonuniformity) using (standard deviation / mean) x 100 (%).

[0289] Experimental Example 4: Evaluation of the physical properties of the polished layer

[0290] (1) Hardness

[0291] The Shore D hardness of the polishing pads prepared in the embodiments and comparative examples was measured. The polishing pads were cut into 2cm × 2cm (thickness: 2mm) pieces and then left to stand for 16 hours at 25°C and 50±5% humidity. The hardness of the polishing pads was then measured using a hardness tester (Type D hardness tester).

[0292] (2) Stretching

[0293] The polishing pads prepared in the respective embodiments and comparative examples were tested using a universal testing machine (UTM) at a speed of 500 mm / min, thereby obtaining the highest strength value just before fracture. The slope of the stress-strain curve in the 20 to 70% region was then calculated using the obtained value.

[0294] (3) elongation

[0295] The polishing pads prepared in the respective embodiments and comparative examples were tested using a universal testing machine (UTM) at a speed of 500 mm / min, thereby measuring the maximum deformation just before fracture, and then the ratio of the maximum deformation to the initial length was expressed as a percentage (%).

[0296] (4) Modulus of elasticity

[0297] The polishing pads prepared in the respective embodiments and comparative examples were tested using a universal testing machine (UTM) at a speed of 500 mm / min, thereby obtaining the highest strength value just before fracture. The slope of the stress-strain curve in the 20 to 70% region was then calculated using the obtained value.

[0298] The results of Experiments 1 to 4 are shown in Table 1 below.

[0299] [Table 1]

[0300]

[0301]

[0302] (*Used pads may indicate that the target polishing rate or target polishing unevenness was not achieved during the polishing process.)

[0303] Based on the physical property evaluation of Experimental Example 4, it can be confirmed that the same values ​​were observed in the Examples and Comparative Examples before and after heat treatment. This may mean that the physical properties of the polishing layer of the polishing pad are not affected by heat treatment.

[0304] Based on the surface roughness measurement results of Experiment Example 1, as shown in Table 1, Figure 8 and Figure 9 As shown. Figure 8 Yes, the result of taking a 3D image of the polished layer of the polished pad (Comparative Example 2) after use; Figure 9Yes, as shown in Examples 1 to 8, this is the result of capturing 3D images of polishing pads that can be reused due to heat treatment. As shown in the above figures, the polishing pads that were originally to be discarded exhibit a uniform red height in terms of surface roughness, thus confirming that the roughness is formed gradually. When the polishing layer described above is used in the polishing process, its polishing rate is low, thus resulting in a decrease in polishing efficiency.

[0305] Conversely, in the case of the embodiments, such as Figure 9 As shown, it can be confirmed that the surface roughness is recovering, which can be verified by the values ​​in Table 1. Specifically, it was confirmed that Sa is in the range of 5 μm to 7 μm, Spk is in the range of 2 μm to 6 μm, and Svk is in the range of 12 μm to 20 μm. It can be confirmed that the measured values ​​are higher than those of the polishing pad of Comparative Example 2, and there is a difference in surface roughness.

[0306] Regarding the surface roughness measurement results, the state of the polished layer was more clearly confirmed through the SEM images in Experiment Example 2. Figure 10 and Figure 12 This is an SEM image of the polishing layer within the polishing pad in Comparative Example 2. Figure 10 It's a photo magnified 100 times. Figure 12 It's a photo magnified 300 times. Based on the above... Figure 10 and Figure 12 It can be confirmed that multiple pores formed on the surface of the polished layer are blocked by the polishing process or formed into a distorted shape.

[0307] on the contrary, Figure 11 and Figure 13 The image is an SEM photograph of the polishing layer in the polishing pad of the embodiment after heat treatment. It can be confirmed that the pores are relatively large and the pore blockage has been eliminated, and the pores are not skewed.

[0308] In the comparison of the polishing performance of Experimental Example 3, the polishing rate of the new polishing pad in Comparative Example 1 was found to be higher. The polishing unevenness was 4.60%, and the polishing rate of the polishing pad that was originally to be discarded in Comparative Example 2 was... The polishing unevenness is 8.80%.

[0309] In Examples 1 to 8, the polishing rate was confirmed to be... The polishing unevenness is below 8.50%, exhibiting higher polishing performance compared to Comparative Example 2. In other words, compared to Comparative Example 2, the polishing rate is improved, and excellent results are also observed in terms of polishing unevenness.

[0310] Although the preferred embodiments of the present invention have been described in detail above, the scope of the present invention is not limited thereto, and various modifications and improvements made by those skilled in the art using the basic concepts of the present invention as defined in the following claims are also within the scope of the present invention.

Claims

1. A method for refurbishing a polishing pad, wherein, The method for refurbishing the polishing pad includes the step of supplying water vapor to the polishing pad. The polishing pad includes a polishing layer with a polishing surface. The polished layer includes multiple pores. The polished surface includes micro-recesses formed by a plurality of the aforementioned pores. The step of supplying water vapor to the polishing pad is performed with the polishing pad mounted on a flat plate, supplying water vapor at 50°C to 120°C for 1 to 10 minutes, and supplying the water vapor while satisfying any one or more of the following conditions (i) to (iii). i) The surface roughness Sa of the polished surface is less than 6 μm; ii) The surface roughness Spk of the polished surface is below 5 μm; iii) The surface roughness Svk of the polished surface is below 16 μm. In the step of supplying water vapor to the polishing pad, according to Equation 1 below, the rate of change of the surface roughness Sa value of the polished surface based on the morphological variation of the micro-recesses is 30% to 70%. [Formula 1] (In r -In f ) / In f ×100 In Equation 1 above, Sa f The surface roughness Sa value of the polished surface is the value of the surface roughness of the polished surface before water vapor is supplied to the polishing pad. Sa r Sa is the surface roughness value of the polished surface after water vapor has been supplied to the polishing pad.

2. The method for refurbishing a polishing pad according to claim 1, wherein, Also includes: The steps for adjusting the polished surface.

3. The method for refurbishing a polishing pad according to claim 1, wherein, After the step of supplying water vapor to the polishing pad, the polishing recovery index (PRI) of the polishing layer is 3.10 to 3.80 according to Equation 2 below. [Equation 2] In Equation 2 above, Sa is the value of the three-dimensional arithmetic mean surface roughness according to ISO 25178. Spk is the value of the average height of the peak protruding from the center of the surface of the polished layer. Svk is the average height of the valleys that bulge downwards from the center of the surface of the polished layer.

4. A method for manufacturing a semiconductor device, wherein, include: The step of mounting a polishing pad, including a polishing layer with a polished surface, onto a flat plate; After placing the polishing object on the polishing surface in such a way that the polished surface of the polishing object is in contact with the polishing surface, the polishing pad and the polishing object are rotated relative to each other under pressure and the polishing object is polished. as well as The step of supplying water vapor to the polishing surface of the polishing pad. The polished layer includes multiple pores. The polished surface includes micro-recesses formed by a plurality of the aforementioned pores. The step of supplying water vapor to the polishing surface of the polishing pad is performed while the polishing pad is mounted on a flat plate, supplying water vapor at 50°C to 120°C for 1 to 10 minutes, and supplying the water vapor while satisfying any one or more of the following conditions (i) to (iii). i) The surface roughness Sa of the polished surface is less than 6 μm; ii) The surface roughness Spk of the polished surface is below 5 μm; iii) The surface roughness Svk of the polished surface is below 16 μm. In the step of supplying water vapor to the polishing pad, according to Equation 1 below, the rate of change of the surface roughness Sa value of the polished surface based on the morphological variation of the micro-recesses is 30% to 70%. [Formula 1] (In r -In f ) / In f ×100 In Equation 1 above, Sa f The surface roughness Sa value of the polished surface is the value of the surface roughness of the polished surface before water vapor is supplied to the polishing pad. Sa r Sa is the surface roughness value of the polished surface after water vapor has been supplied to the polishing pad.

5. The method for manufacturing a semiconductor device according to claim 4, wherein, Also includes: The steps for adjusting the polished surface.

6. A semiconductor device manufacturing apparatus, wherein, include: A flat plate for mounting a polishing pad that includes a polishing layer with a polished surface; A carrier for mounting semiconductor substrates; as well as A water vapor jet section for supplying water vapor to the polishing pad mounted on the flat plate. The polished layer includes multiple pores. The polished surface includes micro-recesses formed by a plurality of the aforementioned pores. The steam injection unit supplies steam at 50°C to 120°C for 1 to 10 minutes while the polishing pad is mounted on the flat plate, and supplies the steam when any one or more of the following conditions (i) to (iii) are met. i) The surface roughness Sa of the polished surface is less than 6 μm; ii) The surface roughness Spk of the polished surface is below 5 μm; iii) The surface roughness Svk of the polished surface is below 16 μm. According to Equation 1 below, the rate of change of the surface roughness Sa value of the polished surface based on the morphological variation of the micro-recesses is 30% to 70%. [Formula 1] (In r -In f ) / In f ×100 In Equation 1 above, Sa f The surface roughness Sa value of the polished surface is the value of the surface roughness of the polished surface before water vapor is supplied to the polishing pad. Sa r Sa is the surface roughness value of the polished surface after water vapor has been supplied to the polishing pad.

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