Chemical mechanical polishing pads

Abstract

We provide pads for chemical mechanical polishing. [Solution] The polishing pad is for polishing at least one of semiconductor, optical, magnetic, or electromechanical substrates. The polishing pad includes a polishing layer comprising a urethane-urea copolymer matrix polymer. The urethane-urea copolymer is a curing product of a urethane-containing polyol prepolymer and an amine curing agent. The urethane-containing polyol prepolymer is a urethane-containing reaction product of components comprising one or more polyols, a silicone oligomer having silicone repeating units and end-capped with ether alcohol, and a polyisocyanate compound, wherein the polyisocyanate compound and the silicone oligomer are end-capped with carbinol groups and react with the polyisocyanate compound to form a urethane-containing polyol prepolymer.

Description

[Technical Field]

[0001] The field of this invention is chemical mechanical polishing and pads useful for chemical mechanical polishing. [Background technology]

[0002] Chemical mechanical planarization (CMP) is a variation of polishing process widely used to flatten or planarize layers of integrated circuit structures in order to accurately construct multilayer three-dimensional electrical circuits. The layers being polished are typically thin films (less than 10,000 angstroms) deposited on the underlying substrate. The objective of CMP is to remove excess material from the wafer surface to create an extremely flat layer of uniform thickness, which extends across the entire wafer area. Controlling the removal rate and ensuring uniformity of removal are crucial.

[0003] CMP (Chemical Polishing) utilizes a liquid containing nano-sized particles, often called a slurry. This is supplied onto the surface of a rotating multilayer polymer sheet, or pad, mounted on a rotating platen. The wafer is mounted on a separate fixture or carrier with separate rotating means and pressed against the pad surface under a controlled load. This results in high-speed relative motion between the wafer and the polishing pad (i.e., high shear rates on both the substrate and pad surfaces). Slurry particles trapped at the pad / wafer junction abrade the wafer surface, resulting in removal. Various types of textures are incorporated into the top surface of the polishing pad to control the speed, prevent hydroplaning, and efficiently transport the slurry beneath the wafer. Fine-scale textures are created by abrading the pad with an array of fine diamonds. This is done to control and increase the removal rate; generally referred to as conditioning. Larger-scale grooves of various patterns and dimensions (e.g., XY, circular, radial) are also incorporated for hydrodynamic and slurry transport regulation.

[0004] It is widely observed that the removal rate during CMP follows the Preston equation, rate = Kp * P * V (where P is the pressure of the pad on the substrate, V is the velocity of the pad on the substrate, and Kp is the so-called Preston coefficient). The Preston coefficient is a lumped sum constant characteristic of the set of consumables used. Some of the most important effects contributing to Kp are: (a) pad contact area (derived mainly from pad texture and surface mechanical properties); (b) concentration of slurry particles on the contact area surface available to do work; and (c) reaction rate between surface particles and the surface of the layer being polished. Effect (a) is determined mainly by pad properties and preparation process. Effect (b) is determined by both pad and slurry, while effect (c) is determined mainly by slurry properties.

[0005] In addition to the removal speed, defects formed on the substrate during polishing can be a problem. For example, highly polishable slurries and / or pads containing hard pads or hard particles can cause scratches on the substrate during polishing. While softer pads can reduce defects, such pads may also have a lower removal speed. Hard or rigid pads can lead not only to higher removal speeds but also to higher defect rates, so achieving a balance between high removal speed and low defect rates is difficult but rewarding.

[0006] The improved pad could offer a balance between high removal speed and low defect rate, and it could be optionally used with cerias slurry at higher pressure, or both, which would constitute a significant improvement in CMP technology. [Overview of the Initiative] [Means for solving the problem]

[0007] This specification discloses a polishing pad suitable for polishing at least one semiconductor, optical, magnetic, or electromechanical substrate, comprising a polishing layer containing a matrix polymer, wherein the matrix polymer is a urethane-urea copolymer which is a curing product of a urethane-containing polyol prepolymer and an amine curing agent, wherein the urethane-containing polyol prepolymer is a urethane-containing reaction product of components comprising one or more polyols, a silicone oligomer having silicone repeating units and end-capped with an ether alcohol, and a polyisocyanate compound, wherein the silicone oligomer is end-capped with a carbinol group and reacts with the polyisocyanate compound to form a urethane-containing polyol prepolymer, the amount of silicone oligomer is 6 to 20 weight percent based on the total weight of the urethane-containing polyol prepolymer, the urethane-containing polyol prepolymer contains 7.5 to 9.5 weight percent of unreacted isocyanate groups, and the molar ratio of reactive groups in the curing agent to isocyanate groups in the prepolymer is in the range of 0.87:1 to 1.05:1.

[0008] Also disclosed is a method for polishing a substrate using the disclosed polishing pad. Polishing with this pad can provide improved removal speed and defect rate compared to polishing under the same conditions using a polishing pad lacking oligomers having silicone repeating units.

[0009] From now on, I will refer to diagrams that are exemplary embodiments, in which similar elements are similarly numbered. [Brief explanation of the drawing]

[0010] [Figure 1] This is a scanning electron microscope (SEM) image at 500x magnification of a portion of the polishing layer of a pad formed using the comparative composition. [Figure 2] This is a scanning electron microscope (SEM) image at 500x magnification of a portion of the polishing layer of a pad as disclosed herein. [Figure 3]This is a scanning electron microscope (SEM) image at 500x magnification of a portion of the polishing layer of a pad as disclosed herein. [Figure 4] This is a scanning electron microscope (SEM) image at 500x magnification of the upper surface of the polished layer of a pad as disclosed herein after polishing. [Figure 5] Scanning electron microscopy (SEM) images of polymers useful in polishing layers, such as those disclosed herein, are shown together with the results represented graphically from energy-dispersive X-ray spectroscopy (EDS) scans of the same sample taken along line a-a'. [Figure 6] These are scanning electron microscopy (SEM) images, along with corresponding images from energy-dispersive X-ray spectroscopy (EDS) scanning of the same sample. [Modes for carrying out the invention]

[0011] The polishing pads disclosed herein are suitable for polishing at least one of semiconductor, optical, magnetic, or electromechanical substrates.

[0012] The pad, combined with a low defect rate, can provide a relatively high removal rate during polishing. The pad can withstand higher polishing pressure and speed. Furthermore, the polishing pad can achieve improved performance by using a hydrophilic polishing pad during polishing. Realizing a hydrophilic polishing pad during polishing facilitates the creation of a thin and efficient pad-wafer gap for efficient polishing.

[0013] Specifically, the disclosed pads have an abrasive layer comprising a polyurethane-urea copolymer having repeating units from a silicone oligomer in addition to repeating units from a polyol and an isocyanate functional compound. Specifically, the silicone oligomer is end-capped with a carbinol group and reacts with the polyisocyanate functional compound to form a urethane-containing polyol prepolymer. This urethane-containing polyol prepolymer reacts with an amine curing agent to form a urethane-urea copolymer. Surprisingly, these pads can offer both improved removal speed and reduced defects compared to similar pads that lack the inclusion of silicone oligomer repeating units in the urethane-urea copolymer.

[0014] The polyurethane can be phase-separated to form silicone-rich domains containing higher concentrations of silicone oligomer-based repeating units surrounded by domains containing polyurethane along with lower concentrations of silicone oligomer-based repeating units. The polished layer comprises at least a three-part copolymer. Advantageously, the three-part copolymer comprises silicone, polyurea, and polyurethane groups. The three-part copolymer has phase-separated silicone-rich domains surrounded by low-silicone oligomer repeating units covalently bonded to the polyurethane groups, with the polyurethane groups bonded to the polyurea groups.

[0015] After phase separation, the silicone-rich domain can have more than 1.5 or 2 times the concentration of elemental silicon found in the low-silicone phase polyurethane surrounding the silicone-rich domain, as measured by energy-dispersive X-ray spectroscopy (EDS). The low-silicone region represents a continuous two-phase mixture of a soft segment and a hard segment. For example, in Figures 2, 3, 4, 5, and 6, as shown in the scanning electron microscopy (SEM) images, the silicone-rich phase-separated domain 14 can be seen within the low-silicone polyurethane domain 10. In Figure 5, the cured polymer with the phase-separated silicone-rich domain 14 is shown in the upper SEM image, while the lower chart is the EDS result from scanning from a-a'. This indicates that there is more elemental silicon where the domain is found. The high amount of elemental silicon in the silicone-rich phase-separated domain 14 is due to the presence of silicone oligomers (e.g., -[-(Si(R')2-O-]) in the silicone-rich domain. n This indicates the concentration of oligomers containing repeating units. Similarly, in Figure 6, the upper SEM image shows phase-separated domains such as 14-a and 14-b, while the lower EDS scan shows that such domains 14-a and 14-b are much brighter, indicating a high concentration of elemental silicon in these domains. Since the silicone oligomer-based repeating units are covalently bonded in the polyurethane, silicone-rich phase-separated domains containing a large amount of silicone oligomer-based repeating units as the main component remain on the surface during and after preparation and polishing. This is considered to facilitate the benefit of improved removal rate, along with a reduction in polishing defects seen in pads that incorporate silicone oligomer-based repeating units as part of the polyurethane into the polishing layer. The size of the silicone-rich phase-separated domains can be from 0.1 to 0.5 or 1 to 10 or less, 9 or less, 8 or less, 7 or less, 6 or less, or 4 or less micrometers, as determined by examination of SEM images of the sample pad.

[0016] The polyurethane-polyurea copolymer can be formed by the reaction of a prepolymer and an amine curing agent.

[0017] The prepolymer is a reaction product of one or more polyols, a silicone-containing oligomer, and a polyisocyanate.

[0018] The polyol can be, for example, a polyether polyol (such as a polyalkylene glycol having 2 to 5 carbon atoms in the alkylene, like poly(oxytetramethylene) glycol, poly(oxypropylene) glycol, poly(oxyethylene) glycol, etc.); a polycarbonate polyol; a polyester polyol; a polycaprolactone polyol; a mixture thereof; a mixture of one or more of them and one or more low molecular weight polyols selected from the group consisting of ethylene glycol; 1,2-propylene glycol; 1,3-propylene glycol, 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; and tripropylene glycol. The prepolymer polyol can be (PTMEG); polypropylene ether glycol (PPG), polyethylene ether glycol (PEG); or optionally a mixture of one or more low molecular weight polyols selected from ethylene glycol; 1,2-propylene glycol; 1,3-propylene glycol; 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; and tripropylene glycol, and optionally a mixture thereof. The polyol can mainly be (for example, 90% by weight or more) polytetramethylene ether glycol.

[0019] The repeating units derived from these polyols (e.g., polyether polyols) can account for 45% to 65% by weight of the prepolymer.

[0020] The silicone-containing oligomer can have a silicone (i.e., -Si(R’)2-O-) repeating unit and a reactive carbinol end cap group that enables reaction with other components to form the prepolymer. For example, the end cap group can be a polyether carbinol group. For example, the silicone-containing oligomer can have the following formula: HO-(R-O) m -L-(Si(R’)2-O) n -L-(O-R) m -OH (where R is preferably an alkylene group having 3 to 5 carbon atoms, more preferably 3 carbon atoms, L is a divalent linking group including a bond or preferably an alkylene group having 1 to 5 carbon atoms, a substituted or unsubstituted Si atom or both, R’ is independently at each occurrence H or an alkyl group having 1, 2 or 3 carbon atoms, preferably R’ is a methyl group, “m” is an integer of at least 5, at least 10 or at least 12, 20 or less, 18 or less or 16 or less, and “n” is an integer of at least 5, at least 10 or at least 12, 20 or less, 18 or less or 16 or less) The amount of the silicone-containing oligomer in the prepolymer can be 6, 7, 8, 9, 10 to 20% by weight or less based on the total weight of the prepolymer.

[0021] The isocyanate is polyfunctional, e.g., a diisocyanate. Examples of diisocyanates include 2,4-toluene diisocyanate; 2,6-toluene diisocyanate; 4,4’-diphenylmethane diisocyanate; 4,4’-methylenebis(cyclohexyl isocyanate) (H 12Examples include MDI; naphthalene-1,5-diisocyanate; toluidine diisocyanate; p-phenylenedi diisocyanate; xylylene diisocyanate; isophorone diisocyanate; hexamethylene diisocyanate; cyclohexane diisocyanate; and mixtures thereof. Diisocyanates are, for example, mixed with toluene diisocyanate and H in weight ratios of 10:90 to 95:5, or 50:50 to 90:10, or 70:30 to 85:15. 12 It may be a mixture with MDI.

[0022] The prepolymer can have an unreacted isocyanate (NCO) concentration of 7.5% to 9.5%, 9%, or 8.5% by weight. The amount of polyisocyanate reacted with the polyol and silicone oligomer is selected to achieve the desired amount of unreacted isocyanate.

[0023] The prepolymer may be a low free isocyanate-terminated urethane prepolymer having a free toluene diisocyanate (TDI) monomer content of less than 0.1% by weight.

[0024] The curing agents are bis(4-amino-2-chloro-3,5-diethylphenyl)methane ("MCDEA"), diethyltoluenediamine (DETDA); 3,5-dimethylthio-2,4-toluenediamine and its isomers; 3,5-diethyltoluene-2,4-diamine and its isomers (e.g., 3,5-diethyltoluene-2,6-diamine); 4,4'-bis(sec-butylamino)diphenylmethane; 1,4-bis(sec-butylamino)benzene, 4,4'-methylene-bis(2-chloroaniline)polytetramethylene oxide-di-p-aminobenzoate; N, N-dialkyldiaminodiphenylmethane; p,p'-methylenedianiline (MDA); m-phenylenediamine (MPDA); 4,4'-methylene-bis(2-chloroaniline) (MBOCA); 4,4'-methylene-bis(2,6-diethylaniline) (MDEA); 4,4'-methylene-bis(2,3-dichloroaniline) (MDCA); 4,4'-diamino-3,3'-diethyl-5,5'-dimethyldiphenylmethane, 2,2',3,3-tetrachlorodiaminodiphenylmethane; trimethylene glycol di-p-aminobenzoate; and mixtures thereof. The curing agent can be used in such an amount that the ratio of reactive groups (e.g., amine groups) on the curing agent that are available to react with the isocyanate groups of the prepolymer is 0.87:1 to 1.05:1.

[0025] The polishing layer of the chemical mechanical polishing pad disclosed herein may further contain a plurality of trace elements. The trace elements may be uniformly dispersed throughout the polishing layer or dispersed according to a gradient from the top to the bottom of the polishing layer. The trace elements may be, for example, encapsulated bubbles, hollow core polymer materials, liquid-filled hollow core polymer materials, water-soluble materials and insoluble phase materials (e.g., mineral oil). More specifically, the plurality of trace elements may be selected from encapsulated bubbles and hollow core polymer materials uniformly distributed throughout the polishing layer. The plurality of trace elements may have a weight-average diameter of less than 150 μm or 50 μm or less, and at least 1 or at least 10 μm. For example, the plurality of trace elements may be polymer microballoons having shell walls of either polyacrylonitrile or vinylidene chloride-polyacrylonitrile copolymer (e.g., ExpanseL® microspheres from Akzo Nobel). Multiple trace elements that provide porosity can be incorporated into the abrasive layer to achieve a porosity of 0-50 volume% or 10-35 volume%. The volume% porosity can be determined by dividing the difference between the specific gravity of the unfilled abrasive layer and the specific gravity of the trace element-containing abrasive layer by the specific gravity of the unfilled abrasive layer.

[0026] The abrasive layers of the polishing pads disclosed herein can be provided in a porous or non-porous (i.e., unfilled) configuration. The abrasive layers of the chemical mechanical polishing pads disclosed herein may be 0.4 to 1.15 g / cm³ as measured according to ASTM D1622 (2014). 3 , or 0.70~1.0 g / cm³ 3 It can have a density of .

[0027] The polishing pads disclosed herein can be manufactured by a method comprising: providing an isocyanate-terminated urethane prepolymer; providing a curing agent component separately; combining the isocyanate-terminated urethane prepolymer and the curing agent component to form a combination; reacting the combination to form a product; forming a polishing layer from the product, such as by splitting the product into thin layers to form a polishing layer of a desired thickness; grooving the polishing layer, such as by machining the polishing layer; and forming a chemical mechanical polishing pad having the polishing layer.

[0028] The abrasive layer of the chemical mechanical polishing pads disclosed herein may have a Shore D hardness of 28 to 75 as measured according to ASTM D2240 (2015).

[0029] The abrasive layer can have an average thickness of 20-150 mils (0.05-0.4 cm), 30-125 mils (0.08-0.3 cm), 40-120 mils (0.1-0.3 cm), or 50-100 mils (0.13-0.25 cm).

[0030] The polishing pads disclosed herein can be adapted to match the platen of a polishing machine. For example, a CMP polishing pad can be adapted to be attached to the platen of a polishing machine (for example, using at least one of pressure-sensitive adhesive or vacuum).

[0031] The polishing pads disclosed herein optionally further include at least one additional layer that is aligned with the polishing layer. For example, a CMP polishing pad may optionally further include a compressible base layer bonded to the polishing layer. The compressible base layer can improve the fit of the polishing layer to the surface of the substrate being polished.

[0032] The polishing pads disclosed herein in their final form may further include textures of one or more dimensions on their upper surface. Such textures may be classified as macrotextures or microtextures depending on their size. Macrotextures can facilitate the control of hydrodynamic response and slurry transport. Macrotextures can include grooves of many configurations and designs, without limitation, such as annular, radial, biased radial and cross-hatching, regularly or cyclically arranged protrusions (e.g., cylinders, pyramids of various shapes), or annular or radial patterns, etc. These may be formed directly on the pad by molding or by a machining process on a thin, uniform sheet. Microtextures include finer-scale features that create clusters of surface roughness at the contact points with the substrate wafer where polishing occurs. For example, microtextures may include, without limitation, textures formed by abrasion in an array of hard particles, such as diamond (often referred to as pad conditioning), either before, during, or after use, and microtextures formed during the pad manufacturing process.

[0033] CMP polishing pads are used in conjunction with polishing slurries, as described in the background art herein. The polishing pads disclosed herein may be used in particular with such slurries, and especially with slurries whose pH is below the isoelectric point pH of the particles being used. For example, ceria has an isoelectric point pH of approximately 6.6. Below this pH, the particle surface has a net positive charge. Above this pH, the particles have a net negative charge. Since the pads disclosed herein can exhibit a high negative charge at their pH, an increase in polishing speed can be achieved when the particles are below their isoelectric point. In addition to the selection of the slurry, additional polishing conditions may include polishing pressure, polishing speed, polishing time, and polishing temperature.

[0034] The polishing pads disclosed herein can be manufactured by a variety of processes that are compatible with thermosetting urethanes. These include mixing the raw materials as described above, casting into a mold, annealing, and slicing into sheets of the desired thickness. Alternatively, they can be fabricated in a more precise net-shape form. For example, the following processes: 1. Thermosetting injection molding (often referred to as "reaction injection molding" or "RIM"); 2. Thermoplastic or thermosetting injection blow molding; 3. Compression molding; or 4. Any similar type of process where a flowable material is placed, solidified, thereby creating at least a portion of the macrotexture or microtexture of the pad can be used. In a molding example: 1. The flowable material is pressed into or onto a structure or substrate; 2. The structure or substrate imparts a surface texture into the material as the material solidifies, and 3. The structure or substrate is then separated from the solidified material. <0's

Example

[0035] Synthesis procedure of prepolymer The prepolymer was synthesized in batches of about 200 - 1000 g. All polyols (polytetramethylene ether glycol (PTMEG) of various molecular weights and a silicone oligomer of the following formula

Chemical formula

[0036] Table 1 shows the weight percentages of the components used to synthesize the prepolymer, based on the total weight of the prepolymer.

[0037] [Table 1]

[0038] Manufacturing of abrasive layer materials If porosity was desired, expandable polymer microspheres were added to the prepolymer after a 4-hour reaction time, or the prepolymer was heated once and degassed with the polymer microspheres by vacuum. The sample used for polishing contained a sufficient distribution of polymer microspheres to reach either the specific gravity or the final density. After degassing and once both components had reached the desired temperature, Ethacure® 300 curing agent was added to the heated prepolymer in an amount sufficient to have an 87% stoichiometry (i.e., the molar ratio of amine groups on the curing agent to NCO groups on the prepolymer is 0.87:1). After mixing, the sample was poured onto a heating plate and stretched using a Teflon® polytetrafluoroethylene coated bar with a spacer set to 175 mil (4.4 mm). The plate was then transferred to an oven and heated to 104°C and held at the temperature for 16 hours. The drawdown was then released.

[0039] Pad manufacturing All pads were 30 inches (76 cm) in diameter and had an 80 mil (2.0 mm) thick top pad, 1010 circular grooves with widths, depths, and pitches of 20 mil, 30 mil, and 120 mil (0.51 mm, 0.76 mm, and 3.05 mm), a pressure-sensitive adhesive film for the sub-pads, Suba IV® polyurethane-impregnated polyester felt sub-pads, and a pressure-sensitive platen adhesive. Plaques of each material set were also prepared for characterization testing, both with and without polymer microsphere fillers.

[0040] Example 1 Compositions of polishing layer materials containing expandable polymer microspheres were prepared, sliced, and then examined using scanning electron microscopy (SEM).

[0041] Figure 1 shows a pad material prepared using prepolymer sample 1 (control) that does not contain silicone oligomers, where the bulk polyurethane matrix 10 and expanded polymer microspheres 12 can be seen. No phase separation was observed in the polyurethane matrix 10.

[0042] In contrast, in Figures 2 and 3, which show pad materials prepared using the bulk polyurethane matrix 10 and expanded polymer microspheres, as well as prepolymer samples 2 and 3, respectively, small phase separation domains 14 from the silicone oligomer repeating units were observed. Figure 3 showed that significantly more phase separation domains 14 resulted in twice as many silicone oligomer-based repeating units in the polymer.

[0043] Example 2 Pads prepared using formulations of samples 1 (control), 2, and 3 were prepared and used for polishing. As shown in Figure 4, the SEM of the top polished surface of the pad prepared using sample 3 shows that the phase separation domains 14 from the repeating units of the silicone oligomer remained on the polished surface after preparation and polishing.

[0044] Example 3 Using the prepolymer formulations of samples 1 (control), 2, and 3, pads were prepared as described above using expandable polymer microspheres and Ethacure® 300 curing agent. These pads were prepared and used for polishing silicon oxide substrates using ceria-based slurry. The results are shown in Table 2. 100 in-situ test refers to cases where 100% continuous preparation occurred during polishing. 20 in-situ refers to cases where the pad was prepared only during 20% ​​of the polishing time. Surprisingly, the use of silicone oligomers in forming the prepolymers both increased the removal rate and reduced defects.

[0045] [Table 2]

[0046] Example 4 The polishing material was prepared using prepolymer 2 substantially as described above, except that expandable polymer microspheres were not used, and Ethacure® 300 curing agent was added to the heated prepolymer in an amount that had a 105% stoichiometry (i.e., the molar ratio of amine groups on the curing agent to NCO groups on the prepolymer was 1.05:1). The polishing material was examined by SEM as shown in the SEM image in Figure 5, and then the polishing material was examined by EDS along the line a-a', and the graph shows the amount of elemental silicon detected by EDS along the scanning line. As can be seen, the amount of elemental silicon was higher in the silicone-rich phase separation domain 14 region than in the surrounding polyurethane 10.

[0047] Example 5 The polishing material was prepared using prepolymer 2 in substantially the same manner as described above, except that expandable polymer microspheres were not used. This polishing material was examined by SEM and EDS. Figure 6 shows the SEM image and EDS scan results of the same sample. Silicone-rich regions are bright spots on the EDS scan, corresponding to phase separation domains such as 14-a and 14-b.

[0048] After immersing the samples in water for 7 days, it was observed that the wet hardness decreased more with increasing content of PPG-end capped silicone diols, as shown in Table 3 below.

[0049] [Table 3]

[0050] An increase in softening occurred despite similar percentage water absorption for all samples. Since PPG increased water absorption and resulted in softening compared to all PTMEG-based prepolymers, and PPG associated with silicone diols, this change appears to be a result of preferential water absorption by silicone-rich phase-separated domains. This preferential water absorption also coincided with intermediate silicone content, which had only a minimal effect, such that the softening was not sufficient to alter bulk measurements. This provides an unexpected benefit beyond offsetting wetting issues with the incorporation of silicone hydrophobic units into CMP pads. For example, limited wetting of slurries on polishing pads can degrade polishing performance, including speed and overall uniformity.

[0051] Upon adjustment, these domains were observed to be present on the surface and found in the land regions between pores, as shown in Figure 3, and an increase in their number and size was observed along with the silicone diol content. Since they are covalently bonded to the material, they are not removed by adjustment as in the case of the composite approach.

[0052] This disclosure further encompasses the following aspects: Embodiment 1: A polishing pad suitable for polishing at least one semiconductor, optical, magnetic, or electromechanical substrate, comprising a polishing layer containing a matrix polymer, wherein the matrix polymer is a urethane-urea copolymer which is a curing product of a urethane-containing polyol prepolymer and an amine curing agent, wherein the polishing pad is suitable for polishing at least one semiconductor, optical, magnetic, or electromechanical substrate, and the urethane-containing polyol prepolymer comprises one or more polyols, a silicone oligomer having silicone repeating units, and a polyisocyanate A polishing pad comprising a urethane-containing reaction product of components including a compound, wherein a silicone oligomer is end-capped with a carbinol group and reacts with a polyisocyanate compound to form a urethane-containing polyol prepolymer, the amount of silicone oligomer is 6 to 20 weight percent based on the total weight of the urethane-containing polyol prepolymer, the urethane-containing polyol prepolymer contains 7.5 to 9.5 weight percent of unreacted isocyanate groups, and the molar ratio of reactive groups in the curing agent to isocyanate groups in the prepolymer is in the range of 0.87:1 to 1.05:1.

[0053] Embodiment 2. The silicone-containing oligomer has the following formula: HO-(RO) m -L-(Si(R')2-O) n -L-(OR) m -OH (In the formula, R is preferably an alkylene group of 3 to 5 carbon atoms, more preferably 3 carbon atoms; L is preferably a divalent linkage group containing a bond or an alkylene group of 1 to 5 carbon atoms, a substituted or unsubstituted Si atom, or both; R' is independently H or an alkyl group of 1, 2, or 3 carbon atoms in each occurrence, preferably R' is a methyl group; "m" is an integer of at least 5, at least 10, or at least 12, 20 or less, 18 or less, or 16 or less; and "n" is an integer of at least 5, at least 10, or at least 12, 20 or less, 18 or less, or 16 or less.) A polishing pad according to embodiment 1, having the following features.

[0054] Embodiment 3. The silicone oligomer is of the formula: HO-(RO) m -L-(Si(R')2-O) n -L-(OR) m A polishing pad according to Embodiment 1, having -OH (wherein R is an alkylene group, L is a bond or divalent linking group, a substituted or unsubstituted Si atom, or both, R' is independently an alkyl group of H or 1, 2 or 3 carbon atoms in each occurrence, "m" is an integer of at least 5, and "n" is an integer of at least 5).

[0055] Embodiment 4. The polishing pad of Embodiment 2, wherein R is an alkylene group of three carbon atoms, L is a divalent linking group containing an alkylene group of 1 to 5 carbon atoms, a substituted or unsubstituted Si atom, or both, R' is a methyl group, and m is an integer from 10 to 18.

[0056] Embodiment 5.1 A polishing pad according to Embodiment 1, 2, or 3, wherein one or more polyols contain polytetramethylene ether glycol.

[0057] Embodiment 6. An abrasive pad according to any one of Embodiments 1 to 5, wherein the polyisocyanate compound comprises 2,4-toluene diisocyanate; 2,6-toluene diisocyanate; 4,4'-diphenylmethane diisocyanate; 4,4'-methylenebis(cyclohexyl isocyanate); naphthalene-1,5-diisocyanate; toluidine diisocyanate; para-phenylenedi isocyanate; xylylene diisocyanate; isophorone diisocyanate; hexamethylene diisocyanate; cyclohexane diisocyanate; or a mixture thereof.

[0058] Embodiment 7. The curing agent is bis(4-amino-2-chloro-3,5-diethylphenyl)methane, diethyltoluenediamine; 3,5-dimethylthio-2,4-toluenediamine and its isomers; 3,5-diethyltoluene-2,4-diamine and its isomers (e.g., 3,5-diethyltoluene-2,6-diamine); 4,4'-bis(sec-butylamino)diphenylmethane; 1,4-bis(sec-butylamino)benzene, 4,4'-methylene-bis(2-chloroaniline)polytetramethyleneoxide-di-p-aminobenzoate; N, A polishing pad according to any one of embodiments 1 to 6, comprising N-dialkyldiaminodiphenylmethane; p,p'-methylenedianiline; m-phenylenediamine; 4,4'-methylene-bis(2-chloroaniline); 4,4'-methylene-bis(2,6-diethylaniline); 4,4'-methylene-bis(2,3-dichloroaniline); 4,4'-diamino3,3'-diethyl-5,5'-dimethyldiphenylmethane, 2,2',3,3-tetrachlorodiaminodiphenylmethane; trimethylene glycol di-p-aminobenzoate; or a mixture thereof.

[0059] Embodiment 8. An abrasive pad according to any one of Embodiments 1 to 7, wherein the abrasive layer is porous.

[0060] Embodiment 9. An abrasive pad according to any one of Embodiments 1 to 8, wherein the abrasive layer comprises expandable or expanded polymer microspheres.

[0061] Embodiment 10. A polishing pad according to Embodiment 2 or 3, wherein R has 3 to 5 carbon atoms, L is an alkylene group of 1 to 5 carbon atoms, a substituted or unsubstituted Si atom, or both, "m" is at least an integer of 10, and "n" is at least an integer of 10.

[0062] Embodiment 11. The polishing pad of Embodiment 2 or 3, wherein R is an alkylene group of three carbon atoms.

[0063] Embodiment 12. A method for polishing a substrate, comprising providing a polishing pad and slurry according to any one of the preceding embodiments, and polishing a substrate using a set of polishing conditions.

[0064] Embodiment 13. The method of Embodiment 8, wherein the removal rate during polishing using the set polishing conditions is higher than the removal rate for polishing using the set polishing conditions but with a pad having a composition that is otherwise similar in composition and density but lacks oligomers containing silicone repeating units, and the number of defects is lower than for polishing using the set polishing conditions but with a pad having a composition that is otherwise similar in composition and density but lacks oligomers containing silicone repeating units.

[0065] All ranges disclosed herein include endpoints, which can be combined independently with each other (for example, the range “25% by weight or less, or more specifically 5% by weight to 20% by weight” encompasses the endpoints and all intermediate values ​​of the range “5% by weight to 25% by weight,” etc.). Furthermore, the upper and lower limits described can be combined to form ranges (for example, “at least 1 or at least 2% by weight” and “10 or 5% by weight or less” can be combined as the range “1 to 10% by weight,” or “1 to 5% by weight,” or “2 to 10% by weight,” or “2 to 5% by weight”).

[0066] This disclosure may include, consist of, or be essentially composed of, any suitable components disclosed herein. This disclosure may be further formulated, or instead, to be substantially devoid of, any components, materials, raw materials, auxiliaries, or chemical species used in prior art compositions or otherwise not necessary for achieving the function and / or purpose of this disclosure.

[0067] All cited patents, patent applications, and other references are incorporated herein by reference in their entirety. However, in the event of any conflict or inconsistency between the terms of this application and the terms of the incorporated references, the terms of this application shall prevail over the conflicting terms of the incorporated references.

[0068] Unless otherwise stated herein, all test standards are the most current standards in effect as of the filing date of this application, or, if priority is claimed, as of the filing date of the earliest priority application in which the test standard appears. [Explanation of Symbols]

[0069] 1. Prepolymer sample 2. Prepolymer Samples 3 Samples 10 Bulk Polyurethane Matrix 12 Polymer microspheres 14 Phase-separated domains

Claims

1. A polishing layer comprising a matrix polymer, wherein the matrix polymer is a urethane-urea copolymer which is a curing product of a urethane-containing polyol prepolymer and an amine curing agent. A polishing pad suitable for polishing at least one of semiconductor, optical, magnetic, or electromechanical substrates, including The urethane-containing polyol prepolymer is a urethane-containing reaction product of constituent elements comprising one or more polyols, a silicone oligomer having silicone repeating units, and a polyisocyanate compound, wherein the silicone oligomer is end-capped with a carbinol group and reacts with the polyisocyanate compound to form the urethane-containing polyol prepolymer. The amount of the silicone oligomer is 6 to 20 weight percent based on the total weight of the urethane-containing polyol prepolymer, the urethane-containing polyol prepolymer contains 7.5 to 9.5 weight percent of unreacted isocyanate groups, and the molar ratio of reactive groups in the curing agent to isocyanate groups in the prepolymer is in the range of 0.87:1 to 1.05:

1. Polishing pad.

2. The aforementioned silicone oligomer is given by formula: HO-(R-O) ｍ -L-(Si(R') ２ -O) ｎ -L-(O-R) ｍ -OH (In the formula, R is an alkylene group, L is a bond or a divalent linkage group, a substituted or unsubstituted Si atom, or both, R' is independently an alkyl group of H or 1, 2, or 3 carbon atoms in each occurrence, "m" is an integer of at least 5, and "n" is an integer of at least 5.) The polishing pad according to claim 1, having the following features.

3. The polishing pad according to claim 2, wherein R is an alkylene group of three carbon atoms, L is a divalent linking group containing an alkylene group of one to five carbon atoms, a substituted or unsubstituted Si atom, or both, R' is a methyl group, and m is an integer from 10 to 18.

4. The polishing pad according to claim 1, wherein the one or more polyols include polytetramethylene ether glycol.

5. The polishing pad according to claim 1, wherein the polyisocyanate compound comprises 2,4-toluene diisocyanate; 2,6-toluene diisocyanate; 4,4'-diphenylmethane diisocyanate; 4,4'-methylenebis(cyclohexyl isocyanate); naphthalene-1,5-diisocyanate; toluidine diisocyanate; para-phenylenedi isocyanate; xylylene diisocyanate; isophorone diisocyanate; hexamethylene diisocyanate; cyclohexane diisocyanate; or a mixture thereof.

6. The curing agents include bis(4-amino-2-chloro-3,5-diethylphenyl)methane, diethyltoluenediamine; 3,5-dimethylthio-2,4-toluenediamine and its isomers; 3,5-diethyltoluene-2,4-diamine and its isomers (e.g., 3,5-diethyltoluene-2,6-diamine); 4,4'-bis(sec-butylamino)diphenylmethane; 1,4-bis(sec-butylamino)benzene, 4,4'-methylene-bis(2-chloroaniline)polytetramethyleneoxide-di-p-aminobenzoate; The polishing pad according to claim 1, comprising N,N-dialkyldiaminodiphenylmethane; p,p'-methylenedianiline; m-phenylenediamine; 4,4'-methylene-bis(2-chloroaniline); 4,4'-methylene-bis(2,6-diethylaniline); 4,4'-methylene-bis(2,3-dichloroaniline); 4,4'-diamino3,3'-diethyl-5,5'-dimethyldiphenylmethane, 2,2',3,3-tetrachlorodiaminodiphenylmethane; trimethylene glycol di-p-aminobenzoate; or a mixture thereof.

7. The polishing pad according to claim 1, wherein the polishing layer is porous.

8. The polishing pad according to claim 1, wherein the polishing layer comprises expandable or expanded polymer microspheres.

9. The polishing pad according to claim 2, wherein R has 3 to 5 carbon atoms, L is an alkylene group of 1 to 5 carbon atoms, a substituted or unsubstituted Si atom, or both, "m" is at least an integer of 10, and "n" is at least an integer of 10.

10. The polishing pad according to claim 2, wherein R is an alkylene group of three carbon atoms.

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