Polishing pad and method for manufacturing semiconductor device by using same

Abstract

A polishing pad according to one implementation comprises a polishing layer, which contains a urethane-based prepolymer and a curing agent, wherein, with respect to the polishing layer, a spin-lattice relaxation time (T1) and a spin-spin relaxation time (T2) measured using TD-NMR satisfy equations 1 and 2, respectively, and thus the performance of the polishing pad can be improved.

Description

Polishing pad and method for manufacturing semiconductor devices using the same

[0001] The embodiment relates to a polishing pad used in a chemical mechanical polishing (CMP) process of a semiconductor device.

[0002]

[0003] The chemical mechanical polishing (CMP) process in the semiconductor manufacturing process is a process in which a semiconductor substrate, such as a wafer, is attached to a head and the platen and the head are moved relative to each other so that they come into contact with the surface of a polishing pad fixed on the platen, thereby flattening the uneven portion of the surface of the semiconductor substrate.

[0004] In these CMP processes, the polishing pad must possess stable physical properties, as it significantly impacts the surface processing quality of the semiconductor substrate. In particular, since the polishing rate of the CMP process can vary significantly depending on the components and properties of the polishing pad, it is necessary to optimize the components and properties of the polishing pad.

[0005] The CMP process can be applied in multiple ways during the semiconductor device manufacturing process. Semiconductor devices typically comprise multiple layers, each containing complex and fine circuit patterns. Furthermore, semiconductor devices are evolving toward smaller individual chips and increasingly complex and finer patterns within each layer. Consequently, the purpose of the CMP process has expanded beyond planarizing circuit wiring during semiconductor device manufacturing to include applications such as circuit wiring separation and surface improvement. Consequently, more precise and reliable CMP performance is required.

[0006] [Prior Art Literature]

[0007] [Patent Document]

[0008] (Patent Document 1) Korean Patent Publication No. 2016-0027075

[0009]

[0010] The inventors of the present invention discovered that when the spin-lattice relaxation time (T1) and spin-spin relaxation time (T2) measured using TD-NMR for the polishing layer satisfy a specific equation, the degree of cross-linking of the polymer is controlled, thereby improving the performance of the polishing pad.

[0011] Accordingly, the task of the embodiment is to provide a polishing pad that has excellent overall properties and performance while minimizing the occurrence of defects and scratches during the CMP process.

[0012]

[0013] According to one embodiment, a polishing pad is provided, which includes a polishing layer comprising a urethane-based prepolymer and a curing agent, wherein the polishing layer satisfies the following equations 1 and 2.

[0014] [Formula 1] T1 ≤ 100 ms

[0015] [Formula 2] T2 ≥ 0.21 ms

[0016] In the above equations 1 and 2,

[0017] T1 is the spin-lattice relaxation time measured at 25°C using TD-NMR,

[0018] T2 is the spin-spin relaxation time measured at 25°C using TD-NMR.

[0019] According to another embodiment, a method for manufacturing a semiconductor device is provided, comprising the step of polishing a surface of a semiconductor substrate using the polishing pad.

[0020]

[0021] A polishing pad according to an embodiment includes a polishing layer including a urethane-based prepolymer and a curing agent, and the polishing layer has spin-lattice relaxation time (T1) and spin-spin relaxation time (T2) measured using TD-NMR that satisfy Equations 1 and 2, respectively, so that the degree of crosslinking of the polymer can be controlled, thereby improving the performance of the polishing pad. In this way, the polishing pad according to the embodiment can maintain excellent overall properties and performance of the polishing pad while minimizing the occurrence of defects and scratches during a CMP process by controlling the spin-lattice relaxation time (T1) and the spin-spin relaxation time (T2) using TD-NMR.

[0022]

[0023] Figure 1 illustrates a schematic process diagram of a semiconductor device manufacturing process according to one embodiment.

[0024] (Explanation of symbols - 100: polishing pad, 200: platen, 300: conditioner, 400: polishing slurry, 510: polishing head, 520: carrier, 600: semiconductor substrate (wafer))

[0025]

[0026] The invention is described in detail below through implementation examples. The implementation examples are not limited to the content disclosed below and may be modified in various ways as long as the spirit of the invention remains unchanged.

[0027] The terms used to refer to each component in this specification are used to distinguish it from other components and are not intended to limit the implementation examples. Furthermore, the singular expressions used in this specification include the plural expressions unless the context clearly dictates otherwise.

[0028] In this specification, when a part is said to "include" a certain component, this does not mean that it excludes other components, but rather that it may include other components, unless otherwise specifically stated.

[0029] In this specification, the description that one component is formed above or below another component, or is connected or joined to one another, encompasses both direct formation, connection, or joining between these components or indirect formation, connection, or joining through another component. It should also be understood that the criteria for each component's position above or below the other may vary depending on the viewing direction.

[0030] All numerical ranges indicating the physical properties, dimensions, etc. of the components described in this specification should be understood to be qualified by the term “about” in all cases unless otherwise specified.

[0031] In the numerical ranges that limit the size, physical properties, etc. of the components described in this specification, if a numerical range limited only to the upper limit and a numerical range limited only to the lower limit are separately exemplified, it should be understood that a numerical range in which these upper and lower limits are combined is also included in the exemplary range.

[0032]

[0033] polishing pad

[0034] A polishing pad according to one embodiment includes a polishing layer including a urethane-based prepolymer and a curing agent, wherein the polishing layer satisfies the following equations 1 and 2.

[0035] [Formula 1] T1 ≤ 100 ms

[0036] [Formula 2] T2 ≥ 0.21 ms

[0037] In the above equations 1 and 2,

[0038] T1 is the spin-lattice relaxation time measured at 25°C using TD-NMR,

[0039] T2 is the spin-spin relaxation time measured at 25°C using TD-NMR.

[0040] TD-NMR (Time Domain Nuclear Magnetic Resonance) is a method that analyzes the relaxation time of protons, which takes place after absorbing the energy of a radio frequency (RF) pulse and then releasing the energy to return to their original state. It can measure the spin-lattice relaxation time (T1), which is the time it takes for 63% of the z-axis component of magnetization M to return after a resonance pulse is applied, and the spin-spin relaxation time (T2), which is the time it takes for the cross-sectional (xy plane) component of M to go from 100% to 37%.

[0041] Specifically, the polishing layer satisfies the following equations 1 and 2.

[0042] [Formula 1] T1 ≤ 100 ms

[0043] [Formula 2] T2 ≥ 0.21 ms

[0044] In the above equations 1 and 2,

[0045] T1 is the spin-lattice relaxation time measured at 25°C using TD-NMR,

[0046] T2 is the spin-spin relaxation time measured at 25°C using TD-NMR.

[0047] In one embodiment, the T1 is 100 ms or less, for example, 95 ms or less, 90 ms or less, 85 ms or less, or 80 ms or less, and may also be 0 ms or more, 10 ms or more, 20 ms or more, 30 ms or more, 40 ms or more, 50 ms or more, 60 ms or more, or 70 ms or more, and specifically 0 ms to 100 ms, 0 ms to 95 ms, 0 ms to 90 ms, 0 ms to 85 ms, 10 ms to 100 ms, 20 ms to 100 ms, 30 ms to 100 ms, 40 ms to 100 ms, 50 ms to 100 ms, 60 ms to 100 ms, 10 ms to It can be 95 ms, 20 ms to 95 ms, 30 ms to 95 ms, 40 ms to 95 ms, or 50 ms to 95 ms.

[0048] In one embodiment, the T2 is 0.21 ms or more, for example, 0.22 ms or more, 0.23 ms or more, 0.24 ms or more, or 0.25 ms or more, and may also be 0.5 ms or less, 0.4 ms or less, 0.3 ms or less, 0.28 ms or less, 0.26 ms or less, 0.25 ms or less, or 0.24 ms or less, and specifically, 0.21 ms to 0.5 ms, 0.21 ms to 0.4 ms, 0.21 ms to 0.3 ms, 0.22 ms to 0.5 ms, 0.22 ms to 0.4 ms, 0.22 ms to 0.3 ms, 0.23 ms to 0.5 ms, 0.23 ms to It can be 0.4 ms, or 0.23 ms to 0.3 ms.

[0049] Since the above T1 and T2 satisfy the above equations 1 and 2, the overall properties and performance of the polishing pad can be maintained excellently, while the occurrence of defects and scratches during the CMP process can be minimized.

[0050] In addition, the polishing pad may have a pad wear rate (PWR) of 40 μm / 10 min or less, measured while injecting deionized water (DIW) at a rate of 150 mL / min under conditions of a platen rotation speed of 90 rpm, a conditioner rotation speed of 120 rpm, and a conditioner load of 6 psi.

[0051] For example, the pad wear rate measured under the above conditions may be 40 μm / 10 min or less, 38 μm / 10 min or less, 36 μm / 10 min or less, 35 μm / 10 min or less, 34 μm / 10 min or less, or 335 μm / 10 min or less, and may also be 10 μm / 10 min or more, 20 μm / 10 min or more, 25 μm / 10 min or more, or 30 μm / 10 min or more, and specifically, may be 10 μm / 10 min to 40 μm / 10 min, 20 μm / 10 min to 40 μm / 10 min, or 25 μm / 10 min to 38 μm / 10 min.

[0052] In addition, when polishing a silicon oxide layer of a silicon wafer in a ceria slurry using the above polishing pad, the polishing rate according to the following mathematical expression 1 may be 1,500 Å / min to 6,000 Å / min.

[0053] [Mathematical Formula 1]

[0054] Polishing rate (Å / min) = Change in film thickness before and after polishing (Å) / Polishing time (min).

[0055] For example, when polishing a silicon oxide film of a silicon wafer in a ceria slurry using the polishing pad, the removal rate may be 1,500 Å / min or more, 1,550 Å / min or more, 1,600 Å / min or more, 1,650 Å / min or more, or 1,700 Å / min or more, and may also be 6,000 Å / min or less, 4,500 Å / min or less, 3,000 Å / min or less, 2,500 Å / min or less, 2,000 Å / min or less, or 1,900 Å / min or less, and specifically, may be 1,500 Å / min to 4,500 Å / min, 1,550 Å / min to 3,000 Å / min, or 1,600 Å / min to 2,500 Å / min. there is.

[0056] The above polishing rate may be, for example, an average polishing rate. Specifically, the polishing rate may be measured after polishing a silicon oxide film by adjusting the polishing load to 4.0 psi, injecting calcined ceria slurry onto the polishing pad at a rate of 250 mL / min, and rotating the platen at 150 rpm for 60 seconds. In addition, the thickness measurement for calculating the polishing rate may be performed, for example, by mounting the silicon wafer on a spin dryer after polishing, rinsing it with purified water, drying it with nitrogen for 15 seconds, and using an optical interference thickness gauge on the dried silicon wafer.

[0057] A polishing pad according to one embodiment includes a polishing layer and a support layer. In addition, an adhesive layer may be inserted between the polishing layer and the support layer.

[0058] Below, each component layer is explained in more detail.

[0059]

[0060] polishing layer

[0061] The above polishing layer provides a polishing surface that comes into contact with a semiconductor substrate during a CMP process and constitutes a top pad in the polishing pad. The above polishing layer comes into contact with the semiconductor substrate during a CMP process and performs polishing.

[0062] In one embodiment, the polishing layer comprises a urethane-based prepolymer and a curing agent. Specifically, the polishing layer comprises a polyurethane-based resin, which is a reaction product of the urethane-based prepolymer and the curing agent, i.e., a cured product of the urethane-based prepolymer.

[0063] In another embodiment, the polishing layer comprises a urethane prepolymer, a curing agent, and a foaming agent. Specifically, the polishing layer comprises a porous polyurethane resin obtained from a reaction product of the urethane prepolymer, the curing agent, and the foaming agent, i.e., a composition in which the above components are mixed.

[0064] The above polishing layer may include a plurality of pores formed from the foaming agent.

[0065] The above pores are dispersed and present within the polishing layer.

[0066] The average diameter of the pores may be, for example, 10 μm to 60 μm, 10 μm to 50 μm, 20 μm to 50 μm, 20 μm to 40 μm, 10 μm to 30 μm, 20 μm to 25 μm, or 30 μm to 50 μm.

[0067] Additionally, the total area of ​​the pores may be 30% to 60%, 35% to 50%, or 35% to 43% of the total area of ​​the polishing layer. Additionally, the total volume of the pores may be 30% to 70%, or 40% to 60% of the total volume of the polishing layer.

[0068] The above polishing layer may have a chlorine (Cl) content of 70,000 ppm or less as analyzed according to the IEC 62321-3-2 standard. For example, the polishing layer may have a chlorine (Cl) content of 65,000 ppm or less, 62,000 ppm or less, or 57,000 ppm or less, as analyzed according to the IEC 62321-3-2 standard, or may be 0 ppm or more, 100 ppm or more, 200 ppm or more, 1,000 ppm or more, 2,500 ppm or more, 5,000 ppm or more, 10,000 ppm or more, or 25,000 ppm or more, and specifically 0 ppm to 70,000 ppm, 100 ppm to 70,000 ppm, 1,000 ppm to 70,000 ppm, 2,500 ppm to 66,000 ppm, 5,000 ppm to 65,000 ppm, 10,000 ppm to It can be 62,000 ppm, 25,000 ppm, or 60,000 ppm. By ensuring that the content of chlorine in the polishing layer satisfies the above range, the overall physical properties and performance of the polishing pad can be maintained excellently, while minimizing the occurrence of defects and scratches during the CMP process.

[0069] The polishing pad according to the above embodiment may have a particle size of debris of 30 ㎛ or less, 25 ㎛ or less, 20 ㎛ or less, 19 ㎛ or less, 18 ㎛ or less, or 17 ㎛ or less, and may also have a particle size of 5 ㎛ or more, 10 ㎛ or more, or 15 ㎛ or more.

[0070] Specifically, the debris may be obtained during conditioning while supplying 300 cc / min of deionized water under the conditions of a platen speed of 93 rpm, a conditioner load of 9 lb, a conditioner speed of 64 rpm, and 19 sweeps / min to the polishing pad, and the particle size of the debris may be an average particle size, i.e., a D50 particle size.

[0071] As a specific example, the D50 particle size of the polishing pad debris obtained during conditioning while supplying deionized water at 300 cc / min under the conditions of a platen speed of 93 rpm, a conditioner load of 9 lb, a conditioner speed of 64 rpm, and 19 sweeps / min may be 30 ㎛ or less.

[0072] As another specific example, when the polishing pad is conditioned while supplying 300 cc / min of deionized water under the conditions of a platen speed of 93 rpm, a conditioner load of 9 lb, a conditioner speed of 64 rpm, and 19 sweeps / min, the D50 particle size of the polishing pad debris obtained may be 10 µm to 30 µm, 10 µm to 25 µm, or 10 µm to 18 µm.

[0073] In addition, the polishing pad according to the above embodiment can measure the zeta potential value of debris within a specific numerical range.

[0074] For example, the zeta potential value of a pH 5.5 aqueous solution containing debris obtained by conditioning the polishing layer at a concentration of 0.01 wt% may be -20 mV or more, -10 mV or more, -5 mV or more, 0 mV or more, 5 mV or more, 7 mV or more, or 10 mV or more, and may also be 40 mV or less, 30 mV or less, 20 mV or less, 15 mV or less, 10 mV or less, or 8 mV or less.

[0075] Specifically, the zeta potential value of the above debris solution may be a positive (+) value.

[0076] As a specific example, the zeta potential value of a pH 5.5 aqueous solution containing debris obtained by conditioning the polishing layer at a concentration of 0.01 wt% may be from -10 mV to 30 mV. As another specific example, the zeta potential value of a pH 5.5 aqueous solution containing debris obtained by conditioning the polishing layer at a concentration of 0.01 wt% may be from 7 mV to 15 mV. As another specific example, the zeta potential value of a pH 5.5 aqueous solution containing debris obtained by conditioning the polishing layer at a concentration of 0.01 wt% may be from -10 mV to 8 mV.

[0077] Within the above preferred range, the zeta potential of the debris is similar to the zeta potential of the abrasive particles (e.g., ceria particles) in the CMP polishing composition (slurry), so that the occurrence of defects can be further reduced. Specifically, the zeta potential quantitatively represents the magnitude of the repulsive force and attractive force between particles caused by the positive / negative ions of the particles in the suspension. When the zeta potentials of the debris and the abrasive particles are similar, the repulsive force between the particles increases, preventing agglomeration, thereby reducing the particle size in the composition, thereby reducing the occurrence of defects and scratches.

[0078] The hardness of the polishing layer may be, for example, 30 Shore D or more, 40 Shore D or more, 50 Shore D or more, or 55 Shore D or more, and may also be 80 Shore D or less, 70 Shore D or less, 65 Shore D or less, or 60 Shore D or less. As a specific example, the hardness of the polishing layer may be 50 Shore D to 80 Shore D, 55 Shore D to 80 Shore D, 50 Shore D to 65 Shore D, 55 Shore D to 70 Shore D, or 55 Shore D to 65 Shore D. The Shore D hardness may be measured using a hardness tester, for example, after cutting the polishing layer into a size of 2 mm in thickness × 5 cm in width × 5 cm in length and storing it at 25°C for 12 hours.

[0079] The tensile strength of the above polishing layer is, for example, 5 N / mm 2 Above, 10 N / mm 2 or more than 15 N / mm 2 It can be ideal, and also 30 N / mm 2 Below, 25 N / mm 2 Less than or equal to 20 N / mm 2 It may be as follows. As a specific example, the tensile strength of the polishing layer is 5 N / mm. 2 Up to 30 N / mm 2 , or 15 N / mm 2 Up to 25 N / mm 2 The tensile strength can be measured, for example, by cutting the polishing layer into a thickness of 2 mm × width of 4 cm × length of 1 cm and performing a tensile test at a speed of 50 mm / min using a universal testing machine (UTM).

[0080] The elongation of the polishing layer may be, for example, 50% or more, 70% or more, 90% or more, 106% or more, or 120% or more, and may also be 300% or less, 250% or less, 200% or less, or 150% or less. As a specific example, the elongation of the polishing layer may be from 50% to 300%, or from 90% to 150%. The elongation may be the elongation at break. The elongation may be obtained, for example, by cutting the polishing layer into a 2 mm thick × 4 cm wide × 1 cm long piece, measuring the maximum deformation length just before breakage in a tensile test at a speed of 50 mm / min using a universal testing machine (UTM), and then calculating the percentage (%) of the maximum deformation length compared to the initial length.

[0081] As a specific example, the polishing layer has a hardness of 55 Shore D to 70 Shore D and a hardness of 15 N / mm. 2 Up to 25 N / mm 2 tensile strength, and an elongation of 90% to 150%.

[0082] The above polishing layer may have grooves on its surface for mechanical polishing. The grooves may have appropriate depth, width, and spacing for mechanical polishing, and are not particularly limited.

[0083] A polishing pad according to one embodiment includes a urethane-based prepolymer.

[0084] A prepolymer generally refers to a polymer with a relatively low molecular weight, with polymerization stopped at an intermediate stage to facilitate molding in the manufacture of a final product. Prepolymers can be molded on their own or after reacting with other polymerizable compounds. For example, a prepolymer can be produced by reacting an isocyanate compound with a polyol.

[0085] The isocyanate compound used in the production of the above urethane-based prepolymer may be one selected from the group consisting of aromatic diisocyanate, aliphatic diisocyanate, alicyclic diisocyanate, and combinations thereof.

[0086] The above isocyanate compound may include, for example, one selected from the group consisting of toluene 2,4-diisocyanate (2,4-TDI), toluene 2,6-diisocyanate (2,6-TDI), naphthalene 1,5-diisocyanate, para-phenylene diisocyanate, tolidine diisocyanate, 4,4'-diphenyl methane diisocyanate, hexamethylene diisocyanate, dicyclohexylmethane diisocyanate, isophorone diisocyanate, and combinations thereof.

[0087] The above polyol is a compound containing at least two hydroxyl groups (-OH) per molecule, and may include, for example, one selected from the group consisting of polyether polyol, polyester polyol, polycarbonate polyol, polycaprolactone polyol, and combinations thereof.

[0088] The polyol may include, for example, one selected from the group consisting of polytetramethylene ether glycol, polypropylene ether glycol, 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, tripropylene glycol, and combinations thereof.

[0089] The polyol may have a weight average molecular weight (Mw) of 100 g / mol to 3,000 g / mol. For example, the weight average molecular weight of the polyol may be 100 g / mol to 3,000 g / mol, 100 g / mol to 2,000 g / mol, or 100 g / mol to 1,800 g / mol.

[0090] According to one embodiment, the polyol may include a low molecular weight polyol having a weight average molecular weight (Mw) of 100 g / mol to 300 g / mol and a high molecular weight polyol having a weight average molecular weight (Mw) of 300 g / mol to 1,800 g / mol.

[0091] Additionally, the urethane-based prepolymer may have a weight average molecular weight (Mw) of 500 g / mol to 3,000 g / mol. For example, the weight average molecular weight of the urethane-based prepolymer may be 500 g / mol to 2,500 g / mol, 1,000 g / mol to 2,000 g / mol, or 1,000 g / mol to 1,500 g / mol.

[0092] According to one embodiment, the isocyanate compound for producing the urethane-based prepolymer may include an aromatic diisocyanate compound, and the aromatic diisocyanate compound may include, for example, 2,4-toluene diisocyanate (2,4-TDI) and 2,6-toluene diisocyanate (2,6-TDI). The polyol compound for producing the urethane-based prepolymer may include polytetramethylene ether glycol (PTMEG) and diethylene glycol (DEG).

[0093] According to another embodiment, the isocyanate compound for producing the urethane-based prepolymer may include an aromatic diisocyanate compound and an alicyclic diisocyanate compound. For example, the aromatic diisocyanate compound may include 2,4-toluene diisocyanate (2,4-TDI) and 2,6-toluene diisocyanate (2,6-TDI), and the alicyclic diisocyanate compound may include dicyclohexylmethane diisocyanate (H12MDI). The polyol compound for producing the urethane-based prepolymer may include polytetramethylene ether glycol (PTMEG) and diethylene glycol (DEG).

[0094] The urethane-based prepolymer may have an isocyanate end group content (NCO%) of 5 wt% or more, 8 wt% or more, 9 wt% or more, or 10 wt% or more, and may be 15 wt% or less, 13 wt% or less, 12 wt% or less, or 11 wt% or less. For example, the urethane-based prepolymer may have an isocyanate end group content (NCO%) of 5 wt% to 15 wt%. As a specific example, the urethane-based prepolymer may have an isocyanate end group content (NCO%) of 8 wt% to 15 wt%, 9 wt% to 15 wt%, 8 wt% to 11 wt%, or 9 wt% to 10 wt%.

[0095] The isocyanate terminal group content (NCO%) of the above urethane prepolymer can be designed by comprehensively controlling the types and contents of the isocyanate compound and polyol compound for producing the urethane prepolymer, the process conditions such as temperature, pressure, and time for producing the urethane prepolymer, and the types and contents of the additives used in producing the urethane prepolymer.

[0096] When the isocyanate terminal group content (NCO%) of the above urethane-based prepolymer satisfies the above-mentioned range, the reaction speed, reaction time, and final cured structure when subsequently reacting the urethane-based prepolymer with a curing agent can be adjusted in a direction advantageous to the polishing performance according to the use and purpose of the final polishing pad.

[0097] According to one embodiment, the isocyanate terminal group content (NCO%) of the urethane-based prepolymer may be 9 wt% to 15 wt%.

[0098] Within the above preferred isocyanate terminal group content (NCO%) range, T1 and T2 can be controlled by adjusting physical properties such as the degree of crosslinking of the polymer constituting the polishing layer, thereby optimizing CMP performance and uniformly controlling quality.

[0099] If the NCO% is less than the above range, the desired polishing performance in terms of polishing rate and flatness may not be realized as electrical characteristics based on the chemical hardening structure within the polishing pad, and there may be a problem in that the lifespan of the polishing pad is reduced due to excessive increase in cutting rate, etc. On the other hand, if the NCO% exceeds the above range, surface defects such as scratches and chatter marks on the semiconductor substrate may increase.

[0100] The curing agent is a compound that chemically reacts with the urethane-based prepolymer to form a final cured structure within the polishing layer, and may include, for example, an amine compound or an alcohol compound. Specifically, the curing agent may include one selected from the group consisting of aromatic amines, aliphatic amines, aromatic alcohols, aliphatic alcohols, and combinations thereof.

[0101] According to one embodiment, the curing agent may include a non-chlorine curing agent that does not contain a chlorine component. For example, the content of the non-chlorine curing agent based on the total weight of the curing agent may be 50 wt% or more, 80 wt% or more, 90 wt% or more, 95 wt% or more, 97 wt% or more, 99 wt% or more, or 99.5 wt% or more, and may also be 100 wt% or less or 99.5 wt% or less, and as specific examples, may be 80 wt% to 100 wt%, 90 wt% to 100 wt%, or 80 wt% to 99.5 wt%. In addition, the content of the chlorine-based curing agent based on the total weight of the curing agent may be 20 wt% or less, 10 wt% or less, 5 wt% or less, 1 wt% or less, or 0.5 wt% or less, or 0.3 wt% or less, and may also be 0 wt% or more, 0.1 wt% or more, or 0.5 wt% or more, and as specific examples, may be 0 wt% to 20 wt%, 0 wt% to 1 wt%, 0 wt% to 0.5 wt%, or 0.5 wt% to 20 wt%.

[0102] The above curing agent may be at least one selected from a solid curing agent and a liquid curing agent.

[0103] The above solid curing agent may contain an active hydrogen group. The above solid curing agent may include an amine group (-NH2) as the active hydrogen group.

[0104] Additionally, the solid curing agent may be an ester compound having two or more benzene rings. Specifically, the solid curing agent may include two or more ester groups within the molecule.

[0105] The solid curing agent may have a weight average molecular weight of, for example, 150 g / mol to 400 g / mol, 150 g / mol to 350 g / mol, 200 g / mol to 350 g / mol, 250 g / mol to 350 g / mol, or 300 g / mol to 350 g / mol. In addition, the solid curing agent may have a melting point (mp) of 100°C to 150°C, 100°C to 140°C, or 110°C to 130°C.

[0106] In one embodiment, the solid curing agent may include at least one selected from the group consisting of 1,3-propanediol bis(4-aminobenzoate) (PDPAB), 4-(4-aminobenzoyl)oxyphenyl 4-aminobenzoate, 4-(4-aminobenzoyl)oxybutyl 4-aminobenzoate, 4-[4-(4-aminobenzoyl)oxy-3-methylbutoxy]butyl 4-aminobenzoate, and methylene bis-methylanthranilate (MBNA).

[0107] The above liquid curing agent may contain an active hydrogen group. The above liquid curing agent may include, as an active hydrogen group, at least one selected from the group consisting of an amine group (-NH2), a hydroxyl group (-OH), a carboxylic acid group (-COOH), an epoxy group, and combinations thereof, and specifically may include an amine group (-NH2).

[0108] Additionally, the liquid curing agent may contain sulfur within the molecule, and specifically may contain two or more sulfur elements within the molecule.

[0109] The above liquid curing agent may have a weight average molecular weight of 50 to 300, for example, 100 to 250, for example, 150 to 250, for example, 200 to 250.

[0110] Additionally, the liquid curing agent may be liquid at room temperature. Alternatively, the liquid curing agent may have a boiling point (bp) of 160°C to 240°C, specifically 170°C to 240°C, and more specifically 170°C to 220°C.

[0111] Examples of the above liquid curing agent may include at least one selected from the group consisting of 3,5-dimethylthio-2,6-diaminotoluene (DMTDA), 2,6-bis(methylthio)-4-methyl-1,3-benzenediamine, and N,N'-bis(sec-butylamino)diphenylmethane.

[0112] In addition, the curing agent may further include other curing agents in addition to the liquid curing agent and the solid curing agent. The other curing agent may be, for example, at least one of an amine compound and an alcohol compound. Specifically, the other curing agent may include at least one compound selected from the group consisting of an aromatic amine, an aliphatic amine, an aromatic alcohol, and an aliphatic alcohol.

[0113] For example, the other curing agent may be at least one selected from the group consisting of diaminodiphenyl methane, diaminodiphenyl sulphone, m-xylylene diamine, isophoronediamine, ethylenediamine, diethylenetriamine, triethylenetetramine, polypropylenediamine, polypropylenetriamine, ethyleneglycol, diethyleneglycol, dipropyleneglycol, butanediol, hexanediol, glycerine, and trimethylolpropane.

[0114] As a specific example, the curing agent may include at least one selected from the group consisting of 4,4'-methylenebis(2-chloroaniline (MOCA), diethyltoluenediamine (DETDA), 3,5-dimethylthio-2,6-diaminotoluene (DMTDA), 1,3-propanediol bis(4-aminobenzoate) (PDPAB), N,N'-bis(sec-butylamino)diphenylmethane, 2,6-bis(methylthio)-4-methyl-1,3-benzenediamine, 4-(4-aminobenzoyl)oxyphenyl 4-aminobenzoate, 4-(4-aminobenzoyl)oxybutyl 4-aminobenzoate, 4-[4-(4-aminobenzoyl)oxy-3-methylbutoxy]butyl 4-aminobenzoate, and methylene bis-methylanthranilate (MBNA). there is.

[0115] The content of the curing agent may be 60 parts by weight or more based on 100 parts by weight of the urethane-based prepolymer. For example, the content of the curing agent may be 62 parts by weight or more, 65 parts by weight or more, or 70 parts by weight or more based on 100 parts by weight of the urethane-based prepolymer, and may also be 100 parts by weight or less, 95 parts by weight or less, 90 parts by weight or less, 85 parts by weight or less, 80 parts by weight or less, or 75 parts by weight or less, and specifically, may be 62 parts by weight to 100 parts by weight, or 65 parts by weight to 90 parts by weight.

[0116] Within the above preferred range of curing agent content, T1 and T2 can be controlled by adjusting the physical properties such as the degree of crosslinking of the polymer constituting the polishing layer, thereby optimizing CMP performance and uniformly controlling quality.

[0117] Additionally, the equivalent ratio of the urethane-based prepolymer and the curing agent may be 1:0.5 to 2. For example, the equivalent ratio of the urethane-based prepolymer and the curing agent may be 1:0.5 to 1.5, 1:0.5 to 1.0, or 1:0.6 to 1.2.

[0118] The above-mentioned foaming agent may include one selected from the group consisting of a solid foaming agent, a gaseous foaming agent, a liquid foaming agent, and a combination thereof as a component for forming a pore structure within the polishing layer.

[0119] According to one embodiment, the foaming agent may be a non-chlorine foaming agent that does not contain a chlorine component, and in particular, may not contain or minimize the use of a chlorine foaming agent component commonly used in the manufacture of polishing pads, such as vinylidene chloride (VDC). For example, the content of the non-chlorine foaming agent based on the total weight of the foaming agent may be 50 wt% or more, 80 wt% or more, 90 wt% or more, 95 wt% or more, 97 wt% or more, 99 wt% or more, or 99.5 wt% or more, and may also be 100 wt% or less or 99.5 wt% or less, and as specific examples, may be 80 wt% to 100 wt%, 90 wt% to 100 wt%, or 80 wt% to 99.5 wt%. In addition, the content of the chlorine-based blowing agent based on the total weight of the blowing agent may be 20 wt% or less, 10 wt% or less, 5 wt% or less, 1 wt% or less, or 0.5 wt% or less, or 0.3 wt% or less, and may also be 0 wt% or more, 0.1 wt% or more, or 0.5 wt% or more, and as specific examples, may be 0 wt% to 20 wt%, 0 wt% to 1 wt%, 0 wt% to 0.5 wt%, or 0.5 wt% to 20 wt%.

[0120] The above-mentioned foaming agent may be at least one selected from a solid foaming agent including hollow particles, a liquid foaming agent using a volatile liquid, and an inert gas.

[0121] For example, the solid foaming agent may include hollow particles that are expanded by heat and have a controlled size. Such a solid foaming agent has the advantage of being able to uniformly control the pore size by being introduced into the raw material in an already expanded form and thus having a uniform particle size.

[0122] In addition, the solid foaming agent may include expandable particles. The expandable particles are particles having a property of being expandable by heat or pressure, etc., and the size within the final polishing layer may be determined by heat or pressure applied during the process of manufacturing the polishing layer. The expandable particles may be introduced into the raw material in a non-expanded particle state in advance, and the final size may be determined by expansion by heat or pressure applied during the process of manufacturing the polishing layer.

[0123] The average particle diameter of the above-mentioned solid foaming agent may be, for example, 5 ㎛ to 100 ㎛, specifically 5 ㎛ to 50 ㎛, or 20 ㎛ to 50 ㎛. The average particle diameter of the above-mentioned solid foaming agent refers to the average particle diameter of the expanded particles themselves when the solid foaming agent is a particle that is introduced into the raw material in an expanded state as described below, and may refer to the average particle diameter of the particles after being expanded by heat or pressure during the manufacturing process when the solid foaming agent is a particle that is introduced into the raw material in an unexpanded state as described below.

[0124] The above-mentioned expandable particle type solid foaming agent may include an outer shell made of a resin material; and an expansion-inducing component present inside the outer shell. These expandable particles may be formed into a hollow structure by vaporizing the expansion-inducing component inside by heat during the manufacturing process.

[0125] For example, the outer shell may include a thermoplastic resin. The thermoplastic resin may be at least one selected from the group consisting of an acrylonitrile-based copolymer, a methacrylonitrile-based copolymer, and an acrylic copolymer.

[0126] The thickness of the outer skin may be, for example, 0.1 ㎛ or more, 0.5 ㎛ or more, 1 ㎛ or more, 2 ㎛ or more, or 3 ㎛ or more, and may also be 15 ㎛ or less, 12 ㎛ or less, or 10 ㎛ or less, and as a specific example, may be 2 ㎛ to 15 ㎛.

[0127] The above expansion-inducing component may include one selected from the group consisting of hydrocarbon compounds, tetraalkylsilane compounds, and combinations thereof. Specifically, the hydrocarbon compound may include one selected from the group consisting of ethane, ethylene, propane, propene, n-butane, isobutene, n-butene, isobutene, n-pentane, isopentane, neopentane, n-hexane, heptane, petroleum ether, and combinations thereof. The tetraalkylsilane compound may include one selected from the group consisting of tetramethylsilane, trimethylethylsilane, trimethylisopropylsilane, trimethyl-n-propylsilane, and combinations thereof.

[0128] The solid foaming agent may include particles treated with an inorganic component. In one embodiment, the solid foaming agent may have a surface treated with silica (SiO2) particles. The inorganic component treatment of the solid foaming agent may prevent agglomeration between the plurality of particles. The chemical, electrical, and / or physical properties of the solid foaming agent treated with an inorganic component may differ from those of a solid foaming agent not treated with an inorganic component.

[0129] Commercially available products of the above-mentioned solid foaming agent include Nouryon's 920DE20d70, 051DET40d25, 051DET40d42, etc., and Matsumoto's F-65DE, F-80DE, FN-80SDE, etc.

[0130] As a specific example, the foaming agent used in the polishing pad according to the above embodiment includes a solid foaming agent, and the solid foaming agent may include at least one selected from the group consisting of an acrylonitrile-based copolymer, a methyl methacrylate-based copolymer, a methacrylonitrile-based copolymer, and an acrylic copolymer.

[0131] The content of the solid foaming agent may be 0.1 parts by weight or more, 0.5 parts by weight or more, or 1 part by weight or more, and may be 5 parts by weight or less, 3 parts by weight or less, or 2 parts by weight or less, based on 100 parts by weight of the urethane-based prepolymer. As a specific example, the content of the solid foaming agent may be 0.1 parts by weight to 5 parts by weight, or 0.5 parts by weight to 2 parts by weight based on 100 parts by weight of the urethane-based prepolymer.

[0132] In one embodiment, the polishing layer includes a foaming agent, and the foaming agent includes at least one selected from the group consisting of an acrylonitrile-based copolymer, a methyl methacrylate-based copolymer, a methacrylonitrile-based copolymer, and an acrylic copolymer, and the content of the foaming agent may be 0.1 to 5 parts by weight based on 100 parts by weight of the urethane-based prepolymer.

[0133] The type and content of the solid foaming agent can be designed according to the desired pore structure and properties of the polishing layer.

[0134] Meanwhile, a liquid foaming agent can form pores by being introduced into the reaction process in which the prepolymer and curing agent are mixed and reacted, but does not participate in the reaction between the prepolymer and curing agent. Furthermore, the liquid foaming agent is physically vaporized by the heat generated during the reaction process in which the prepolymer and curing agent are mixed and reacted, thereby forming pores.

[0135] The volatile liquid blowing agent does not react with isocyanate groups, amide groups, and alcohol groups, and can be liquid at 25°C. Specifically, the volatile liquid blowing agent can be selected from the group consisting of cyclopentane, n-pentane, cyclohexane, n-butyl acetate, bis(nonafluorobutyl)(trifluoromethyl)amine; and perfluorotributylamine, perfluoro-N-methylmorpholine, perfluorotripentylamine, and perfluorohexane. Commercially available products of the above perfluoro compounds include FC-40 (3M), FC-43 (3M), FC-70 (3M), FC-72 (3M), FC-770 (3M), FC-3283 (3M), FC-3284 (3M), etc.

[0136] In addition, the foaming agent may include a gaseous foaming agent. For example, the foaming agent may include a solid foaming agent and a gaseous foaming agent.

[0137] The above-mentioned gaseous foaming agent may contain an inert gas. The above-mentioned gaseous foaming agent may be introduced during the reaction process of the urethane-based prepolymer and the curing agent and used as a pore-forming element.

[0138] The type of the above inert gas is not particularly limited as long as it is a gas that does not participate in the reaction between the urethane-based prepolymer and the curing agent. For example, the above inert gas may include one selected from the group consisting of nitrogen gas (N2), carbon dioxide gas (CO2), argon gas (Ar), helium gas (He), and combinations thereof.

[0139] The type and content of the gas-phase foaming agent can be designed according to the desired pore structure and properties of the polishing layer.

[0140] The inert gas may be introduced in a volume corresponding to 10% to 30% of the total volume of the composition. Specifically, the inert gas may be introduced in a volume corresponding to 15% to 30% of the total volume of the composition. Specifically, the gaseous foaming agent may be introduced through a predetermined injection line during the process of mixing the urethane-based prepolymer, the solid foaming agent, and the curing agent. For example, the injection speed of the gaseous foaming agent may be about 0.8 L / min to about 2.0 L / min, about 0.8 L / min to about 1.8 L / min, about 0.8 L / min to about 1.7 L / min, 1.0 L / min to about 2.0 L / min, 1.0 L / min to about 1.8 L / min, or about 1.0 L / min to about 1.7 L / min.

[0141] The composition for manufacturing the above polishing layer may further include other additives such as a surfactant, a reaction rate control agent, etc. The names "surfactant", "reaction rate control agent", etc. are arbitrary names based on the main role of the corresponding substance, and each corresponding substance does not necessarily perform only the function limited to the role of the corresponding name.

[0142] The surfactant is not particularly limited as long as it is a substance that prevents phenomena such as aggregation or overlapping of pores. For example, the surfactant may include a silicone-based surfactant.

[0143] The surfactant may be used in an amount of 0.2 parts by weight to 2 parts by weight based on 100 parts by weight of the urethane-based prepolymer. Specifically, the surfactant may be included in an amount of 0.2 parts by weight to 1.9 parts by weight, 0.2 parts by weight to 1.8 parts by weight, 0.2 parts by weight to 1.7 parts by weight, 0.2 parts by weight to 1.6 parts by weight, 0.2 parts by weight to 1.5 parts by weight, or 0.5 parts by weight to 1.5 parts by weight based on 100 parts by weight of the urethane-based prepolymer. When the surfactant is included in an amount within the above range, pores derived from the gas-phase foaming agent can be stably formed and maintained within the mold.

[0144] The above reaction rate controller acts as a reaction accelerator or reaction retarder, and depending on the purpose, a reaction accelerator, a reaction retarder, or both may be used. The reaction rate controller may include a reaction accelerator. For example, the reaction accelerator may be one or more reaction accelerators selected from the group consisting of tertiary amine compounds and organometallic compounds.

[0145] Specifically, the reaction rate modifier is triethylenediamine, dimethylethanolamine, tetramethylbutanediamine, 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-azanoboneine, dibutyltin dilaurate, stannous octoate, dibutyltin diacetate, dioctyltin diacetate, dibutyltin maleate, dibutyltin It may include at least one selected from the group consisting of di-2-ethylhexanoate and dibutyltin dimercaptide. Specifically, the reaction rate modifier may include at least one selected from the group consisting of benzyldimethylamine, N,N-dimethylcyclohexylamine, and triethylamine.

[0146] The reaction rate controller may be used in an amount of 0.05 parts by weight to 2 parts by weight based on 100 parts by weight of the urethane-based prepolymer. Specifically, the reaction rate controller may be used in an amount of 0.05 parts by weight to 1.8 parts by weight, 0.05 parts by weight to 1.7 parts by weight, 0.05 parts by weight to 1.6 parts by weight, 0.1 parts by weight to 1.5 parts by weight, 0.1 parts by weight to 0.3 parts by weight, 0.2 parts by weight to 1.8 parts by weight, 0.2 parts by weight to 1.7 parts by weight, 0.2 parts by weight to 1.6 parts by weight, 0.2 parts by weight to 1.5 parts by weight, or 0.5 parts by weight to 1 part by weight, based on 100 parts by weight of the urethane-based prepolymer. When the above reaction rate control agent is used in the content range described above, the curing reaction rate of the prepolymer composition can be appropriately controlled to form a polishing layer having pores of a desired size and hardness.

[0147] The thickness of the above polishing layer may be 0.8 mm to 5.0 mm, 1.0 mm to 4.0 mm, 1.0 mm to 3.0 mm, 1.5 mm to 2.5 mm, 1.7 mm to 2.3 mm, or 2.0 mm to 2.1 mm. Within the above range, the basic properties as a polishing pad can be sufficiently exhibited while minimizing the particle size deviation between the upper and lower portions of the pores.

[0148]

[0149] support base

[0150] The above support layer constitutes a bottom pad, and supports the polishing layer while absorbing and dispersing external impact applied to the polishing layer, thereby minimizing damage and defects to the polishing target during a polishing process using the polishing pad.

[0151] The support layer may include, but is not limited to, non-woven fabric or suede.

[0152] In one embodiment, the support layer may be a resin-impregnated nonwoven fabric. The nonwoven fabric may be a fiber nonwoven fabric comprising one selected from the group consisting of polyester fibers, polyamide fibers, polypropylene fibers, polyethylene fibers, and combinations thereof.

[0153] The resin impregnated in the above nonwoven fabric may include 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.

[0154] The thickness of the support layer may be 0.3 mm or more, or 0.5 mm or more, or 3 mm or less, 2 mm or less, or 1 mm or less. As a specific example, the thickness of the support layer may be 0.3 mm to 3 mm, or 0.5 mm to 1 mm.

[0155] The hardness of the support layer may be 50 Asker C or more, 60 Asker C or more, or 70 Asker C or more, or 100 Asker C or less, 90 Asker C or less, or 80 Asker C or less. As a specific example, the hardness of the support layer may be 50 Asker C to 100 Asker C, or 60 Asker C to 90 Asker C.

[0156] Additionally, an adhesive layer may be inserted between the polishing layer (upper pad) and the support layer (lower pad).

[0157] The above adhesive layer may include a hot melt adhesive. The hot melt adhesive may be at least one selected from the group consisting of polyurethane resins, polyester resins, ethylene-vinyl acetate resins, polyamide resins, and polyolefin resins. Specifically, the hot melt adhesive may be at least one selected from the group consisting of polyurethane resins and polyester resins.

[0158] In addition, a double-sided tape can be applied to the lower part of the support layer, and when applied to CMP equipment, the release paper of the double-sided tape can be removed and attached to the platen for use.

[0159]

[0160] Method for manufacturing polishing pads

[0161] A method for manufacturing a polishing pad according to one embodiment includes the steps of: manufacturing a polishing pad composition including a urethane-based prepolymer, a foaming agent, and a curing agent; injecting the polishing pad composition into a mold and curing it to manufacture a polishing layer; and laminating the polishing layer with a support layer.

[0162] The specific types and contents of the above urethane-based prepolymer, curing agent, and foaming agent are as exemplified above.

[0163] As a specific example, the foaming agent includes a solid foaming agent, and the solid foaming agent includes at least one selected from the group consisting of an acrylonitrile-based copolymer, a methyl methacrylate-based copolymer, a methacrylonitrile-based copolymer, and an acrylic copolymer, and the curing agent includes diethyltoluenediamine (DETDA), 3,5-dimethylthio-2,6-diaminotoluene (DMTDA), 1,3-propanediol bis(4-aminobenzoate) (PDPAB), N,N'-bis(sec-butylamino)diphenylmethane, 2,6-bis(methylthio)-4-methyl-1,3-benzenediamine, 4-(4-aminobenzoyl)oxyphenyl 4-aminobenzoate, 4-(4-aminobenzoyl)oxybutyl 4-aminobenzoate, It may include at least one selected from the group consisting of 4-[4-(4-aminobenzoyl)oxy-3-methylbutoxy]butyl 4-aminobenzoate, and methylene bis-methylanthranilate (MBNA).

[0164] The above polishing pad composition can be manufactured by sequentially or simultaneously mixing a urethane-based prepolymer, a foaming agent, and a curing agent.

[0165] As an example, the step of manufacturing the polishing pad composition may be performed by mixing a urethane-based prepolymer with a curing agent and then further mixing with a foaming agent, or by mixing the urethane-based prepolymer with the foaming agent and then further mixing with the curing agent.

[0166] As another example, the urethane prepolymer, curing agent, and blowing agent may be introduced into the mixing process substantially at approximately the same time, and when blowing agent, surfactant, and inert gas are further added, these may also be introduced into the mixing process substantially at approximately the same time.

[0167] As another example, a urethane prepolymer, a blowing agent, and a surfactant may be mixed in advance, and then a curing agent may be added, or a curing agent and an inert gas may be added together.

[0168] In the above mixing, the urethane prepolymer and the curing agent are mixed to initiate the reaction, and the blowing agent and inert gas can be evenly dispersed within the raw material. At this time, the reaction rate control agent can control the reaction rate by intervening in the reaction of the urethane prepolymer and the curing agent from the beginning of the reaction. Specifically, the mixing can be performed at a speed of 1,000 to 10,000 rpm, or 4,000 to 7,000 rpm. Within the above speed range, the inert gas and the blowing agent can be more advantageously dispersed evenly within the raw material.

[0169] In addition, the step of manufacturing the polishing pad composition can be performed under conditions of 50°C to 150°C, and, if necessary, can be performed under vacuum degassing conditions.

[0170] When the foaming agent includes a solid foaming agent, the step of preparing the polishing pad composition may include a step of preparing a first preliminary composition by mixing the urethane-based prepolymer and the solid foaming agent; and a step of preparing a second preliminary composition by mixing the first preliminary composition and a curing agent.

[0171] The viscosity of the first preliminary composition may be from about 1,000 cps to about 2,000 cps at about 80°C, for example, from about 1,000 cps to about 1,800 cps, for example, from about 1,000 cps to about 1,600 cps, for example, from about 1,000 cps to about 1,500 cps.

[0172] When the foaming agent comprises a vapor-phase foaming agent, the step of preparing the polishing pad composition may include the step of preparing a third preliminary composition comprising the urethane-based prepolymer and the curing agent; and the step of injecting the vapor-phase foaming agent into the third preliminary composition to prepare a fourth preliminary composition. In one embodiment, the third preliminary composition may further comprise a solid-phase foaming agent.

[0173] In one embodiment, the process for manufacturing the polishing layer may include the steps of preparing a mold preheated to a first temperature; and the steps of injecting the polishing pad composition into the preheated mold and curing it; and the steps of post-curing the cured polishing pad composition under a second temperature condition higher than the preheating temperature.

[0174] In one embodiment, the temperature difference between the first temperature and the second temperature can be about 10°C to about 40°C, for example, about 10°C to about 35°C, for example, about 15°C to about 35°C. In one embodiment, the first temperature can be about 60°C to about 100°C, for example, about 65°C to about 95°C, for example, about 70°C to about 90°C. In one embodiment, the second temperature can be about 100°C to about 130°C, for example, about 100°C to about 125°C, for example, about 100°C to about 120°C.

[0175] The step of curing the above polishing pad composition under the first temperature may be performed for about 5 minutes to about 60 minutes, for example, for about 5 minutes to about 40 minutes, for example, for about 5 minutes to about 30 minutes, for example, for about 5 minutes to about 25 minutes.

[0176] The step of post-curing the polishing pad composition cured under the first temperature at the second temperature may 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.

[0177] Afterwards, the step of injecting the polishing pad composition into the mold and then curing it is performed under temperature conditions of 60°C to 120°C and pressure of 50 kg / m 2 Up to 200 kg / m 2 It can be performed under pressure conditions.

[0178] In addition, the manufacturing method may further include a process for cutting the surface of the obtained polishing pad, a process for forming grooves on the surface, a process for bonding with a lower layer, an inspection process, a packaging process, etc. These processes may be performed using a conventional polishing pad manufacturing method.

[0179] As an example, the method for manufacturing the polishing pad may include a step of processing at least one surface of the polishing layer. The step of processing at least one surface of the polishing layer may include at least one of a step of forming a groove on at least one surface of the polishing layer; a step of line turning at least one surface of the polishing layer; and a step of roughening at least one surface of the polishing layer.

[0180] The groove may include at least one of concentric grooves spaced apart from the center of the polishing layer at a predetermined interval; and radial grooves continuously connected from the center of the polishing layer to the edge of the polishing layer. The line turning may be performed by a method of cutting off the polishing layer to a predetermined thickness using a cutting tool. The roughening may be performed by a method of processing the surface of the polishing layer with a sanding roller.

[0181]

[0182] Method for manufacturing semiconductor devices

[0183] A method for manufacturing a semiconductor device according to another embodiment includes a step of polishing a surface of a semiconductor substrate using the polishing pad.

[0184] Specifically, the method for manufacturing the semiconductor device may include: providing a polishing pad according to the embodiment; and polishing the surface of the semiconductor substrate by rotating the polishing surface of the polishing layer relative to the surface of the semiconductor substrate so that the polishing surface and the surface of the semiconductor substrate come into contact with each other.

[0185] Fig. 1 illustrates a semiconductor device manufacturing process using a polishing pad according to an embodiment. Referring to Fig. 1, after the polishing pad (100) according to the embodiment is mounted on a platen (200), a semiconductor substrate (600) to be polished is placed on the polishing pad (100). At this time, the polishing surface of the semiconductor substrate (600) is in direct contact with the polishing surface of the polishing pad (100). For polishing, a polishing slurry (400) may be sprayed onto the polishing pad through a nozzle. The flow rate of the polishing slurry (400) supplied through the nozzle is about 10 cm. 3 / min to about 1,000 cm 3 / min can be selected according to the purpose within the range, for example, about 50 cm 3 / min to about 500 cm 3 / min but is not limited to this.

[0186] Thereafter, the semiconductor substrate (600) and the polishing pad (100) can be rotated relative to each other, so that the surface of the semiconductor substrate (600) can be polished. At this time, the rotation direction of the semiconductor substrate (600) and the rotation direction of the polishing pad (100) can be the same direction or opposite directions. The rotation speeds of the semiconductor substrate (600) and the polishing pad (100) can be selected according to the purpose within the range of about 10 rpm to about 500 rpm, for example, about 30 rpm to about 200 rpm, but are not limited thereto.

[0187] The semiconductor substrate (600) is mounted on the polishing head (510) and is pressed against the polishing surface of the polishing pad (100) with a predetermined load so that the surface can be polished. The load applied to the polishing surface of the polishing pad (100) by the polishing head (510) on the surface of the semiconductor substrate (600) is approximately 1 gf / cm. 2 About 1,000 gf / cm 2 It can be selected according to the purpose in the range, for example, about 10 gf / cm 2 About 800 gf / cm 2 It may include, but is not limited to.

[0188] In one embodiment, the semiconductor substrate (600) to be polished may include an oxide film, a tungsten film, or a composite film thereof. Specifically, the semiconductor substrate (600) may include an oxide film, a tungsten film, or a composite film of an oxide film and a tungsten film. The composite film of the oxide film and the tungsten film may be a multilayer film in which the tungsten film is laminated on one surface of the oxide film, or may be a single layer film in which an oxide region and a tungsten region are mixed within one layer. Since the polishing object has such film properties and the polishing pad has the properties according to the embodiment, a semiconductor device manufactured according to the method for manufacturing a semiconductor device can have minimized defects.

[0189] In one embodiment, the method for manufacturing the semiconductor device may further include, in the step of polishing the polishing target, a step of supplying one of the oxide film polishing slurry and the tungsten film polishing slurry; or a step of sequentially supplying the oxide film polishing slurry and the tungsten film polishing slurry to the polishing surface.

[0190] For example, when the semiconductor substrate to be polished includes an oxide film, the method for manufacturing the semiconductor device may include a step of supplying a slurry for polishing the oxide film. When the semiconductor substrate includes a tungsten film, the method for manufacturing the semiconductor device may include a step of supplying a slurry for polishing the tungsten film. When the semiconductor substrate includes a composite film of an oxide film and a tungsten film, the method for manufacturing the semiconductor device may include a step of sequentially supplying the slurry for polishing the oxide film and the slurry for polishing the tungsten film to the polishing surface. At this time, depending on the process, the slurry for polishing the oxide film may be supplied first and then the slurry for polishing the tungsten film may be supplied later, or the slurry for polishing the tungsten film may be supplied first and then the slurry for polishing the oxide film may be supplied later.

[0191] In one embodiment, the method for manufacturing the semiconductor device may further include a step of processing the polishing surface of the polishing pad (100) through a conditioner (470) simultaneously with polishing the semiconductor substrate (600) in order to maintain the polishing surface of the polishing pad (100) in a state suitable for polishing.

[0192] The polishing pad according to the above embodiment can minimize the occurrence of defects and scratches during the CMP process while maintaining excellent overall properties and performance of the polishing pad by controlling the spin-lattice relaxation time (T1) and the spin-spin relaxation time (T2) using TD-NMR.

[0193]

[0194] The above content is explained in more detail with the following examples. However, the scope of implementation is not limited to the following examples.

[0195]

[0196] Example 1: Manufacturing of a polishing pad

[0197] (1) Manufacturing of urethane prepolymer

[0198] Toluene diisocyanate (TDI), dicyclohexyl methane diisocyanate (H12MDI), polytetramethylene ether glycol (PTMEG), and diethylene glycol (DEG) were placed in a four-necked flask and reacted at 80°C for 3 hours to produce a urethane prepolymer having a terminal NCO group content (NCO%) of 10%.

[0199] (2) Manufacturing of polishing pads

[0200] A casting device equipped with a tank and an input line for supplying raw materials such as a urethane prepolymer, a curing agent, and an inert gas, respectively, was prepared. Specifically, the urethane prepolymer manufactured in step (1), the curing agent (4,4'-methylenebis(2-chloroaniline); MOCA), the solid blowing agent (average particle size: 20 μm), the inert gas (N2), and the silicone surfactant (manufacturer: Evonik) were each charged into the tank. At this time, 70 parts by weight of the curing agent, 5 parts by weight of the surfactant, and 5 parts by weight of the solid blowing agent were charged based on 100 parts by weight of the urethane prepolymer, and the inert gas was charged at a rate of 2 L / min.

[0201] Afterwards, the raw materials were fed into the mixing head at a constant speed through each input line and stirred (rotation speed of the mixing head: approximately 5,000 rpm). A mold (1,000 mm × 1,000 mm × 3 mm) was prepared, preheated at 80°C, and the stirred mixture was discharged into the mold and reacted to obtain a solidified cake-shaped molded body. Thereafter, the top and bottom of the molded body were cut to produce a polishing layer for a top pad.

[0202] Afterwards, the polishing layer was subjected to surface milling and groove forming processes, and the polishing pad was manufactured by bonding it to a support layer for the bottom pad using a hot melt adhesive. At this time, double-sided tape (442JS, 3M) was bonded to the bottom of the support layer so that it could be attached to the platen of the CMP equipment.

[0203]

[0204] Examples 2 to 6: Manufacturing of polishing pads

[0205] A polishing pad was manufactured in the same manner as in Example 1, except that the composition and its contents were different as shown in Table 1 below.

[0206]

[0207] Comparative Examples 1 to 6: Manufacturing of Polishing Pads

[0208] A polishing pad was manufactured in the same manner as in Example 1, except that the composition and its contents were different as shown in Table 2 below.

[0209]

[0210] Classification Example 1 Example 2 Example 3 Example 4 Example 5 Example 6 Urethane prepolymer NCO % (%) 10 10 10 10 10 10 10 Content (parts by weight) 100 100 100 100 100 100 Curing agent (parts by weight) MOCA 708086 --- DMTDA --- 708086 Surfactant (parts by weight) 555555 Solid foaming agent (parts by weight) 555555 Inert gas (L / min) 222222

[0211] ClassificationComparative Example 1Comparative Example 2Comparative Example 3Comparative Example 4Comparative Example 5Comparative Example 6Urethane PrepolymerNCO%(%)888888Content (weight parts)100100100100100100Curifier (weight parts)MOCA708086---DMTDA---708086Surfactant (weight parts)555555Solid foaming agent (weight parts)555555Inert gas (L / min)222222

[0212]

[0213] Test Example 1: Hardness

[0214] The hardness of the polishing layers of Examples 1 to 6 and Comparative Examples 1 to 6 was measured. Specifically, the polishing layers were cut into 2 mm thick × 5 cm wide × 5 cm long sizes, stored at 25°C for 12 hours, and then the Shore D hardness was measured using a hardness tester.

[0215]

[0216] Test Example 2: Elongation

[0217] For the polishing layers of Examples 1 to 6 and Comparative Examples 1 to 6, elongation was measured. Specifically, the polishing layers were cut into pieces measuring 2 mm in thickness × 4 cm in width × 1 cm in length, and the maximum deformation length just before fracture was measured in a tensile test at a speed of 50 mm / min using a universal testing machine (UTM), and then the percentage (%) of the maximum deformation length relative to the initial length was calculated.

[0218]

[0219] Test Example 3: TD-NMR

[0220] For the polishing layers of Examples 1 to 6 and Comparative Examples 1 to 6, the spin-lattice relaxation time (T1) and the spin-spin relaxation time (T2) were measured using TD-NMR.

[0221] Specifically, 10 g of the above polishing layer is 3 mm 2 The sample was cut into the size of , and T1 and T2 were measured using TD-NMR (product name: mini-spec, manufacturer: Bruker) at room temperature (25℃). At this time, T1 and T2 were calculated as the time taken to recover to the original equilibrium state by 63%.

[0222]

[0223] Test Example 4: Chlorine (Cl) content

[0224] The chlorine content was measured for the polishing layers of Examples 1 to 6 and Comparative Examples 1 to 6. Specifically, a circular sample with a diameter of 3 cm and a height of 0.3 cm was prepared from the polishing layer, and the chlorine content in the sample was measured by IEC 62321-3-2, an international standard method for measuring specific substances in polymers by combustion-ion chromatography (C-IC).

[0225]

[0226] Test Example 5: Polishing rate

[0227] For the polishing pads of Examples 1 to 6 and Comparative Examples 1 to 6, the polishing pads were fixed on the platen of the CMP equipment, the silicon oxide film of a silicon wafer (diameter: 300 mm) was set downward, and the CMP process was performed to measure the polishing rate.

[0228] Specifically, the silicon oxide film was polished by adjusting the polishing load to 4.0 psi and rotating the platen at 150 rpm for 60 seconds while injecting the calcined ceria slurry onto the polishing pad at a rate of 250 mL / min. After polishing, the silicon wafer was removed from the carrier, mounted on a spin dryer, rinsed with purified water, and dried with nitrogen for 15 seconds. The difference in thickness of the silicon oxide film before and after polishing was measured using an optical interferometer thickness meter (model name: SI-F80R, manufacturer: Kyence), and the polishing rate was calculated according to the following mathematical equation 1.

[0229] [Mathematical Formula 1]

[0230] Polishing rate (Å / min) = Change in film thickness before and after polishing (Å) / Polishing time (min)

[0231]

[0232] Test Example 6: Pad Wear Rate (PWR)

[0233] The pad wear rate (PWR) was measured for the polishing pads of Examples 1 to 6 and Comparative Examples 1 to 6. The polishing pads were set on the platen of the CMP equipment, and under the conditions of a platen rotation speed of 90 rpm, a conditioner rotation speed of 120 rpm, and a conditioner load of 6 psi, deionized water (DIW) was injected at a rate of 150 mL / min, and the change in the thickness of the polishing layer was measured for 10 minutes.

[0234]

[0235] Classification Example 1 Example 2 Example 3 Example 4 Example 5 Example 6 Polishing layer thickness (mm) 2 2 2 2 2 Hardness (Shore D) 5 8.8 6 0.0 6 1.0 5 6.9 5 8.0 5 9.8 Specific gravity (g / cc) 0.79 0.79 0.79 0.79 0.79 0.79 Elongation (%) 1 1 1 1 3 0 1 5 0 1 0 1 1 2 7 1 4 3 Cl Content (ppm) 46,32152,81056,786234226239 Polishing pad TD-NMRT1 (ms) 89.183.479.088.683.979.7 T2 (ms) 0.2390.2400.2440.2370.2440.253 Measurement temperature (℃) 252525252525 Polishing rate (Å / min) 1,7601,6471,5351,7911,6631,579 PWR (μm / 10min) 34.333.431.736.534.332.0

[0236] Classification Comparison Example 1 Comparison Example 2 Comparison Example 3 Comparison Example 4 Comparison Example 5 Comparison Example 6 Polishing layer thickness (mm) 2 2 2 2 2 Hardness (Shore D) 5 0.0 5 2.0 5 3.0 4 8.7 5 1.1 5 1.9 Specific gravity (g / cc) 0.7 9 0.7 9 0.7 9 0.7 9 0.7 9 0.7 9 Elongation (%) 1 3 0 1 5 0 1 7 0 1 1 9 1 3 8 1 5 2 Cl Content (ppm) 40,23445,42646,839289275246 Polishing pad TD-NMRT1 (ms) 82.678.976.781.778.676.5 T2 (ms) 0.1870.1940.2030.1880.1960.208 Measurement temperature (℃) 252525252525 Polishing rate (Å / min) 1,5901,4631,3791,5871,4281,392 PWR (μm / 10min) 32.529.327.034.532.129.8

[0237]

[0238] As shown in Tables 1 and 2 above, the polishing pads of Examples 1 to 6 were measured to have T1 and T2 of 100 ms or less and 0.21 ms or more, respectively, and the chlorine content, polishing rate, PWR, and other properties of the polishing pads were all within desirable ranges.

Claims

1. Includes a polishing layer containing a urethane-based prepolymer and a curing agent, The above polishing layer is a polishing pad that satisfies the following equations 1 and 2: [Formula 1] T1 ≤ 100 ms [Formula 2] T2 ≥ 0.21 ms In the above equations 1 and 2, T1 is the spin-lattice relaxation time measured at 25°C using TD-NMR, T2 is the spin-spin relaxation time measured at 25°C using TD-NMR.

2. In paragraph 1, The above polishing pad is a polishing pad having a pad wear rate (PWR) of 40 μm / 10 min or less while injecting deionized water (DIW) at a rate of 150 mL / min under conditions of a platen rotation speed of 90 rpm, a conditioner rotation speed of 120 rpm, and a conditioner load of 6 psi.

3. In paragraph 1, A polishing pad, wherein the above polishing layer has a chlorine (Cl) content of 70,000 ppm or less as analyzed according to the IEC 62321-3-2 standard.

4. In paragraph 1, A polishing pad having a polishing rate of 1,500 Å / min to 6,000 Å / min according to the following mathematical formula 1 when polishing a silicon oxide layer of a silicon wafer in a ceria slurry using the above polishing pad: [Mathematical Formula 1] Polishing rate (Å / min) = Change in film thickness before and after polishing (Å) / Polishing time (min).

5. In paragraph 1, A polishing pad in which the content of the above hardener is 60 parts by weight or more based on 100 parts by weight of the above urethane-based prepolymer.

6. In paragraph 1, A polishing pad, wherein the curing agent comprises at least one selected from the group consisting of 4,4'-methylenebis(2-chloroaniline (MOCA), diethyltoluenediamine (DETDA), 3,5-dimethylthio-2,6-diaminotoluene (DMTDA), 1,3-propanediol bis(4-aminobenzoate) (PDPAB), N,N'-bis(sec-butylamino)diphenylmethane, 2,6-bis(methylthio)-4-methyl-1,3-benzenediamine, 4-(4-aminobenzoyl)oxyphenyl 4-aminobenzoate, 4-(4-aminobenzoyl)oxybutyl 4-aminobenzoate, 4-[4-(4-aminobenzoyl)oxy-3-methylbutoxy]butyl 4-aminobenzoate, and methylene bis-methylanthranilate (MBNA).

7. In paragraph 1, A polishing pad wherein the above urethane-based prepolymer has an isocyanate terminal group content (NCO%) of 5 wt% to 15 wt%.

8. In paragraph 1, The above polishing layer contains a foaming agent, The above-mentioned foaming agent comprises at least one selected from the group consisting of an acrylonitrile-based copolymer, a methyl methacrylate-based copolymer, a methacrylonitrile-based copolymer, and an acrylic copolymer, A polishing pad in which the content of the foaming agent is 0.1 to 5 parts by weight based on 100 parts by weight of the urethane-based prepolymer.

9. In paragraph 1, The above polishing layer is, Hardness of 55 Shore D to 70 Shore D, 15 N / mm 2 Up to 25 N / mm 2 Tensile strength of, and A polishing pad having an elongation of 90% to 150%.

10. A method for manufacturing a semiconductor device, comprising a step of polishing the surface of a semiconductor substrate using the polishing pad of claim 1.

Images