Polishing composition with printed particles and method for fabricating printed particles

Abstract

This disclosure provides a polishing composition comprising a plurality of printed particles and a method for preparing the printed particles. The polishing composition includes a liquid carrier and a plurality of printed particles dispersed in the liquid carrier. The printed particles are prepared by a lamination process.

Description

[Technical Field]

[0001] This application claims priority to U.S. Patent Application No. 18 / 794,068 (i.e., priority date "August 5, 2024"), the contents of which are incorporated herein by reference in their entirety.

[0002] This disclosure relates to a grinding composition having printing particles and a method for preparing the same. [Previous Technology]

[0003] Semiconductor components are used in various electronic applications, such as personal computers, mobile phones, digital cameras, and other electronic devices. The size of semiconductor components continues to shrink to meet the ever-increasing demand for computing power. However, various problems arise during the miniaturization process, and these problems are constantly increasing. Therefore, challenges remain to be overcome in improving quality, yield, performance, reliability, and reducing complexity.

[0004] The above description of "prior art" is merely to provide background information and does not acknowledge that the above description of "prior art" discloses the subject matter of this disclosure. It does not constitute prior art of this disclosure, and no description of the above "prior art" should be considered part of this case. [Summary of the Invention]

[0005] One aspect of this disclosure provides a grinding composition comprising a liquid carrier and a plurality of printed particles dispersed in the liquid carrier. The printed particles are prepared by additive manufacturing.

[0006] Another aspect of this disclosure provides a polishing composition comprising a liquid carrier; a plurality of first printed particles dispersed in the liquid carrier; and a plurality of second printed particles dispersed in the liquid carrier. The first printed particles and the second printed particles are prepared by a lamination process. The size of the first printed particles and the size of the second printed particles are different.

[0007] Another aspect of this disclosure provides a method for preparing printed particles, comprising: preparing a photosensitive material and placing the photosensitive material on a displacement platform; activating a femtosecond laser to generate a plurality of femtosecond laser beams; modulating the femtosecond laser beams using an external path modulation unit; using a computer-controlled image capturing device to capture a first layer profile of the plurality of printed particles, such that the modulated femtosecond laser beams form a plurality of parallel beams arranged according to the first layer profile; focusing the parallel beams through a plurality of focusing lenses in the photosensitive material to form a planar image composed of multiple focal points, wherein the photosensitive material at all focal points is The process involves: solidification to achieve a one-time projection of the first layer cross-sectional structure for forming the first layer cross-sectional view of the printed particles; using a computer to control the displacement platform to move a distance equal to the thickness of one layer cross-section of the printed particles, with the direction of movement of the displacement platform parallel to the direction in which the femtosecond laser beams irradiate the photosensitive material; controlling the image capturing device via the computer to capture cross-sectional views of subsequent layers of the printed particles using laser; and after forming a subsequent layer cross-sectional view of the printed particles, using the computer to control the displacement platform to move a distance equal to the thickness of one layer cross-section of the printed particles until the printed particles are formed.

[0008] Because the structural differences (e.g., shape, size, surface charge, etc.) between individual particles formed through the lamination process are small, batch-to-batch variation in CMP operations using this polishing composition can be reduced. As a result, process stability of the CMP operation can be improved and process control simplified. Furthermore, the shape, size, surface charge, polarity, and / or size distribution of these printed particles can be customized through the lamination process to meet the requirements of various processes.

[0009] The technical features and advantages of this disclosure have been summarized quite extensively above to provide a better understanding of the detailed description of this disclosure below. Other technical features and advantages that form the subject matter of the claims of this disclosure will be described below. Those skilled in the art to which this disclosure pertains will understand that the concepts and specific embodiments disclosed below can be readily used to modify or design other structures or processes to achieve the same purpose as this disclosure. Those skilled in the art to which this disclosure pertains will also understand that such equivalent constructions cannot depart from the spirit and scope of this disclosure as defined in the appended claims.

Implementation Method

[0011] The following disclosure provides many different embodiments or examples to implement different components of the embodiments disclosed herein. Specific examples of elements and their arrangements are described below to simplify the embodiments disclosed herein. These are merely examples and should not be construed as limiting the scope of the embodiments disclosed herein. For example, when the description refers to a first component being formed "on" or "on" a second component, it may include embodiments where the first and second components are in direct contact, or embodiments where other components are formed between them without direct contact. Furthermore, reference numerals and / or designations may be repeated in different embodiments of this disclosure. These repetitions are for simplification and clarity and are not intended to define relationships between the different embodiments and / or structures discussed.

[0012] Furthermore, spatial terms used, such as “below,” “below,” “lower,” “above,” “higher,” and similar terms, are used to facilitate the description of the relationship between one element or component shown in the diagram and another. These spatial relation terms are used to cover different orientations of elements in use or operation, other than those depicted in the diagram. If an element may be rotated to different orientations (rotated 90 degrees or other orientations), the spatial relation adjectives used therein can be interpreted in the same way.

[0013] It should be understood that when a component or layer is referred to as being “connected to” or “coupled to” another component or layer, it may be directly connected to or coupled to another component or layer, or there may be an intermediate component or layer.

[0014] It should be understood that although the terms "first," "second," etc., may be used herein to describe various elements, these elements should not be limited by these terms. Unless otherwise stated, these terms are used only to distinguish one element from another. Thus, for example, without departing from the teachings of this disclosure, the first element, first component, or first part discussed below may be referred to as the second element, second component, or second part.

[0015] Unless the context otherwise indicates, the use of terms such as “same,” “equal,” “plane,” or “coplanar” in reference to orientation, layout, location, shape, size, quantity, or other measures does not necessarily imply identical orientation, layout, location, shape, size, quantity, or other measures, but is intended to cover orientation, layout, location, shape, size, quantity, or other measures that are substantially identical within acceptable variations, for example, due to manufacturing processes. The term “substantially” may be used in this document to reflect this meaning. For example, items described as “substantially same,” “substantially equal,” or “substantially plane” may be exactly the same, equal, or plane, or may be the same, equal, or plane within acceptable variations, for example, due to manufacturing processes.

[0016] As stated herein, unless otherwise specified, all percentages of composition are expressed in weight (wt%) or moles (mol%) of total composition. Unless otherwise specified, the disclosure of ranges includes endpoints and includes all distinct values ​​throughout the range and further subdivisions.

[0017] In this disclosure, semiconductor devices generally refer to devices that can perform functions by utilizing the characteristics of semiconductors, and electro-optical devices, light-emitting display devices, semiconductor circuits and electronic devices are all included in the category of semiconductor devices.

[0018] It should be noted that in the description disclosed herein, above or up corresponds to the direction of the arrow in the Z direction, and below or down corresponds to the direction of the arrow opposite to the Z direction.

[0019] In a Chemical Mechanical Planarization (CMP) operation, a substrate (e.g., a wafer) to be polished is mounted on a carrier assembly and brought into contact with a polishing pad within a CMP polishing tool. The carrier assembly applies a controlled pressure to the substrate, causing it to press against the polishing pad. An external driving force causes the substrate and polishing pad to move relative to each other. This relative movement between the substrate and polishing pad abrades and removes a portion of the material from the substrate surface, thereby polishing the substrate.

[0020] Abrasive compositions (also known as abrasive slurries, CMP slurries, and CMP compositions) for polishing various metal (such as tungsten) and non-metal (such as silicon oxide) layers on semiconductor substrates may include abrasive particles suspended in an aqueous solution and various chemical additives, such as oxidants, chelating agents, catalysts, topography control agents, buffers, and similar materials.

[0021] The chemical activity of the grinding composition and / or the mechanical action of the abrasive particles suspended in the grinding composition can further enhance the grinding process.

[0022] In this disclosure, an abrasive composition may be provided. In some embodiments, the abrasive composition may include a liquid carrier and a plurality of (colloidal) printed particles dispersed in the liquid carrier. In some embodiments, the printing particle manufacturing technique may include additive manufacturing. In some embodiments, the printing particle manufacturing technique may include, for example, three-dimensional printing (3D printing).

[0023] In some embodiments, the fabrication techniques for printed particles may include, for example, two-photon polymerization, projection microstereolithography, direct ink writing, or other applicable layering fabrication techniques.

[0024] In some embodiments, the fabrication technique for printed particles may include, for example, two-photon polymerization. This technique introduces a femtosecond laser as a light source into the fabrication of printed particles. This technique generally uses a longer wavelength femtosecond laser as the light source, focusing the laser beam onto the photosensitive material to be cured through a focusing objective lens. The photosensitive material undergoes a polymerization reaction at the focal point through two-photon absorption; however, other parts of the laser path do not undergo two-photon absorption due to the lower laser intensity; simultaneously, due to the lower laser energy, no corresponding single-photon absorption process occurs, thus two-photon polymerization is limited to the focal point. As the laser focal point moves within the photosensitive material, the photosensitive material cures along the trajectory of the focal point, and the uncured photosensitive material is removed using an organic solvent, thus achieving the processing of the photosensitive material.

[0025] Figure 1 shows a schematic diagram of the system structure for preparing printed particles by two-photon polymerization using the femtosecond laser disclosed herein.

[0026] Referring to FIG1, a system for preparing printed particles (also known as target objects) by two-photon polymerization using a femtosecond laser may include a femtosecond laser 11, an external optical path modulation unit 12, an image capturing device 13, a focusing lens 14, a photosensitive material 15, a displacement platform 16, a computer 17, and a monitoring device 18.

[0027] In some embodiments, a femtosecond laser 11 is used to generate a femtosecond laser, an external optical path modulation unit 12 modulates the femtosecond laser, and an image capturing device 13 captures cross-sectional views of the target object layer by layer, so that the modulated femtosecond laser forms parallel beams arranged according to the cross-sectional views of each layer. A focusing lens 14 focuses the parallel beams arranged according to the cross-sectional views of each layer onto a photosensitive material 15 to form a planar view composed of a plurality of focal points. The photosensitive material at all focal points is cured, thereby realizing a one-time projection for the cross-sectional structure of each layer of the target object. A displacement platform 16 fine-tunes the position of the photosensitive material 15 placed on it. A computer 17 controls the displacement platform 16 and the image capturing device 13. A monitoring device 18 monitors the curing process of the photosensitive material 15 in real time.

[0028] In some embodiments, the glass slide 19 may be fixed on the displacement platform 16 to support the photosensitive material 15. In some embodiments, the monitoring device 18 may use a CCD (Charged Coupled Device) image sensor as a core component. In addition, a scanning array lens may be disposed between the image capturing device 13 and the focusing lens 14, which further improves the process speed due to the faster response speed of the scanning array lens.

[0029] In some embodiments, the image capturing device 13 can be controlled by the computer 17 to form cross-sectional views of the target object. A femtosecond laser beam can form a plurality of parallel femtosecond laser beams arranged according to the cross-sectional views, thereby achieving layer-by-layer curing of the photosensitive material. Therefore, the displacement platform 16 only needs to move along the cross-sectional thickness of the target object.

[0030] In some embodiments, the image capturing device 13 may not form cross-sectional views of each layer of the target object. Instead, the image capturing device 13 may split a femtosecond laser beam into a plurality of parallel femtosecond laser beams to achieve multifocal parallel curing on the photosensitive material, thereby simultaneously manufacturing multiple target objects. Thus, the displacement platform 16 moves according to a preset trajectory, which corresponds to the distribution of all curing points of the target object to be prepared.

[0031] In some embodiments, a dynamic image capturing device is used as the image capturing device 13. The dynamic image capturing device may include a plurality of pixel units, which are turned on under the control of the computer 17 to form cross-sectional views of the target object at various layers on the dynamic image capturing device. Each pixel unit of the dynamic image capturing device is turned on or off under the control of the computer 17; and when the femtosecond laser 11 irradiates the dynamic image capturing device, each pixel unit in the turned-on state reflects or transmits the femtosecond laser 11, thereby splitting a beam of femtosecond laser 11 into multiple beams of femtosecond laser 11 arranged according to a specific shape, thereby realizing the target object.

[0032] In some embodiments, the external optical path modulation unit 12 may include, but is not limited to, a regenerative amplifier 121, a shutter 122, an attenuator 123, a collimating lens group 124, and an aperture stop 125 sequentially arranged on the femtosecond laser's travel path. The femtosecond laser generated by the femtosecond laser 11 is an ultrashort pulse laser, which needs to be modulated by the external optical path modulation unit 12 to achieve the curing of the photosensitive material 15.

[0033] Specifically, during the curing process, the regenerative amplifier 121 amplifies the energy of the femtosecond laser; and the shutter 122 controls the on / off state of the amplified beam, while the attenuator 123 adjusts the beam energy. By controlling the beam through the attenuator 123, the center intensity at the focal point of each beam can be adjusted, thereby controlling the process resolution. Then, a collimating lens group 124 is used, which includes a short focal length lens 124a and a long focal length lens 124b. Since the laser energy exhibits a Gaussian distribution in space, the light intensity at the edge of the laser beam is greater than that at the center. To reduce the difference in light intensity across the image capture profile caused by uneven light intensity distribution across the beam profile, the beam needs to be collimated and amplified by the collimating lens group 124, making the light intensity distribution in the central region of the laser beam relatively uniform. Next, an aperture stop 125 is used to filter the edges of the beam, resulting in a femtosecond laser beam with an approximately uniform light intensity distribution across the profile.

[0034] It should be noted that, in addition to the components that modulate the femtosecond laser as described above, other components may also be provided on the path of the femtosecond laser and in front of the image capturing device 13 as needed. For example, in order to make the system structure for preparing printed particles more compact, a single reflector may be provided on the path of the femtosecond laser and behind the aperture stop 125.

[0035] In some embodiments, the control of the image capturing device 13 by the computer 17 may include: modeling the structure of the target object through the computer 17, and converting the model obtained by modeling into a digital voltage signal through the computer 17 to load onto the image capturing device 13, thereby forming cross-sectional views of the target object at various layers. The computer 17 can realize computer-aided design through a software control unit set in the computer 17, establish a three-dimensional model of the target object to be prepared, divide the established three-dimensional model into multiple layers of cross-sectional views, and decompose each layer of cross-sectional views point by point to obtain the cross-sectional view of the corresponding layer composed of multiple points. It should be noted that, optionally, the design software in the software control unit can be selected from existing commercial software, such as CAD (Computer Aided Design), wherein optionally, the CAD file can be in STL (Standard Template Library) file format.

[0036] In some embodiments, the photosensitive material 15 may include a solution of a first photopolymer precursor, a second photopolymer precursor, a photoinitiator, and a photoinhibitor. In some embodiments, the photosensitive material 15 may include colloidal nanoparticles of a first material having the first and second photopolymer precursors, a solution of a photoinitiator, and a photoinhibitor.

[0037] In some embodiments, the first material may include, for example, silicon oxide, aluminum oxide, cerium oxide, or a combination thereof. In some embodiments, the refractive index of the photopolymer precursor mixture must match the refractive index of the first material to obtain a transparent ink to eliminate light extinction and scattering. In some embodiments, the photosensitive material 15 must have high thermal conductivity to avoid instantaneous vaporization by a femtosecond laser with megawatts of peak power. In some embodiments, the photosensitive material 15 must be homogeneous and well dispersed to maintain nanometer-level resolution and avoid localized vaporization.

[0038] In some embodiments, the nanoparticles may include polyethylene glycol functional groups chemically attached to the nanoparticles.

[0039] In some embodiments, the size of the nanoparticles may be between about 5 nm and about 50 nm, or between about 8 nm and about 25 nm. In some embodiments, the photosensitive material 15 may include (colloidal) nanoparticles in the range of a lower limit selected from 20, 25, 30, 35, 40, 45, 50, and 55 wt% to an upper limit selected from 30, 35, 40, 45, 50, 55, and 60 wt%, wherein any lower limit may be paired with any mathematically feasible upper limit.

[0040] In some embodiments, the mixture of the first photopolymer precursor and the second photopolymer precursor may have the same refractive index as the first material and may be completely removed during any subsequent annealing process. In some embodiments, the mixture of the first photopolymer precursor and the second photopolymer precursor may have the same refractive index as nanoparticles.

[0041] In some embodiments, the first photopolymer precursor and the second photopolymer precursor may be small molecule acrylates. In some embodiments, the molecular weight of the first photopolymer precursor and the second photopolymer precursor may be less than 10,000 g / mole. In some embodiments, the refractive index of the mixture of the first photopolymer precursor and the second photopolymer precursor may be about 1.5. In some embodiments, the mixture of the first photopolymer precursor and the second photopolymer precursor may be a liquid at room temperature. In some embodiments, a suitable photopolymer precursor may be selected from photopolymer precursors composed of carbon, oxygen, and hydrogen, wherein the photopolymer precursor may participate in free radical reactions.

[0042] In some embodiments, the first photopolymer precursor and the second photopolymer precursor may include, for example, trimethylolpropane ethoxylate triacrylate, poly(ethylene glycol) diacrylate, pentaerythritol tetraacrylate, ethylene glycol diacrylate, trimethylolpropane ethoxylate triacrylate, 2-hydroxyethyl methacrylate, pentaerythritol triacrylate, or a combination thereof.

[0043] In some embodiments, the first photopolymer precursor and the second photopolymer precursor may include the same polyethylene glycol functional groups as the nanoparticles to ensure that the nanoparticles have excellent miscibility and dispersibility in the polymer precursor.

[0044] In some embodiments, the first photopolymer precursor and the second photopolymer precursor may be included in the photosensitive material 15 in a ratio ranging from 1:3 to 3:1 relative to each other. For example, in some embodiments, the first photopolymer precursor and the second photopolymer precursor may be included in the photosensitive material 15 in ratios ranging from 1:3 to 1:2, 1:3 to 2:1, 2:1 to 3:1, or 1:2 to 3:1 relative to each other. In some embodiments, the photosensitive material 15 may include one or more photopolymer precursors, such as the first and second photopolymer precursors, ranging from a lower limit selected from 40, 45, 50, 55, 60, 65, and 70 wt% to an upper limit selected from 45, 50, 55, 60, 65, 70, 75, and 80 wt%, wherein any lower limit may be paired with any mathematically feasible upper limit.

[0045] In some embodiments, the photoinitiator may be, for example, 4,4'-bis(diethylamino)benzophenone, 2-benzyl-2-(dimethylamino)-4'-morpholinobutyrophenone, phenylbis(2,4,6-trimethylbenzoyl)phosphine oxide, or diphenyl(2,4,6-trimethylbenzoyl)phosphine oxide. (oxide), acetophenone, thioxanthen-9-one, 2-benzyl-2-(dimethylamino)-4'-morpholinobutyrophenone, or combinations thereof. In some embodiments, the photosensitive material 15 may include a photoinitiator in an amount ranging from 0.1, 0.2, 0.4, 0.6, 1.0, 1.3, and 1.5 wt% to 0.3, 0.5, 0.7, 1, 1.2, 1.5, 1.8, and 2.0 wt%, wherein any lower limit may be paired with any mathematically feasible upper limit.

[0046] In some embodiments, the photoinhibitor may be any polymerization inhibitor capable of dissolving in the photopolymer precursor or a mixture thereof. For example, in one or more embodiments, the photoinhibitor may be one or more selected from hydroquinone, 4-methoxyphenol, mequinol, butylated hydroxytoluene, quinone methide, or combinations thereof. In some embodiments, the photosensitive material 15 may include a photoinitiator in an amount ranging from 0.05, 0.08, 0.10, 0.20, 0.30, 0.40, 0.50, and 0.60 wt% to 0.10, 0.15, 0.20, 0.30, 0.40, 0.50, 0.60, 0.80, and 1.00 wt%, wherein any lower limit may be paired with any mathematically feasible upper limit.

[0047] In some embodiments, the photosensitive material 15 may include one or more rare earth salts selected from Er³⁺, Tm³⁺, Yb³⁺, Eu³⁺, and Nd³⁺, such as erbium(III) chloride hexahydrate, ytterbium(III) chloride hexahydrate, thium(III) chloride hexahydrate, europium(III) chloride hexahydrate, neodymium(III) chloride hydrate, or combinations thereof. In some embodiments, the photosensitive material 15 may include one or more rare earth salts in a content ranging from 1.0, 1.5, 2.0, 2.5, and 3.0 wt% to 2.0, 2.5, 3.0, 3.5, 4.0, and 5.0 wt%, wherein any lower limit can be paired with any mathematically feasible upper limit.

[0048] According to the system for preparing printed particles (i.e., target objects) through two-photon polymerization using a femtosecond laser 11, an image capturing device 13 can be provided in the optical path of the printed particles prepared by the femtosecond laser 11. This arrangement can split a single beam of femtosecond laser 11 into multiple parallel beams, enabling the simultaneous curing of multiple target objects. Furthermore, it is possible to achieve a one-time projection of cross-sectional views of each layer of the target object, and the cross-sectional views of each layer may be different. Therefore, this system can prepare complex three-dimensional target objects, significantly improving preparation efficiency and process flow.

[0049] Furthermore, during the layer-by-layer curing process, the displacement platform only needs to move along the cross-sectional thickness direction of the target object, without needing to move point-by-point along the two-dimensional plane. This method substantially reduces the time required to form each layer of the target object, improves preparation efficiency and process flow, and reduces the accuracy requirements for positioning in the two-dimensional plane. As a result, the preparation process is simplified and the difficulty is reduced.

[0050] In some embodiments, the printed particles may be spherical, elliptical, rhombohedral, tetrahedral, cubic, cuboid, or other applicable shapes.

[0051] In some embodiments, the size of the printed particles may be between about 20 nm and about 200 nm, about 30 nm and about 180 nm, about 40 nm and about 150 nm, about 50 nm and about 100 nm, or about 20 nm and about 50 nm. In some embodiments, the standard deviation of the printed particle size may be between about 1 nm and about 10 nm, about 1 nm and about 5 nm, or about 1 nm and about 3 nm. In some embodiments, the standard deviation of the printed particle size may be less than 2 nm.

[0052] In some embodiments, the printed particles may be combined with a filtration process to further reduce size variations between the printed particles.

[0053] Figure 2 shows a flowchart of a method 10 for preparing printed particles by two-photon polymerization using the femtosecond laser disclosed herein.

[0054] Referring to Figure 2, in step S11, a photosensitive material 15 can be prepared and placed on a displacement platform 16.

[0055] Referring to Figure 2, in step S13, the femtosecond laser 11 can be activated to generate a femtosecond laser beam.

[0056] Referring to Figure 2, in step S15, the femtosecond laser beam can be modulated through the external optical path modulation unit 12.

[0057] Referring to Figure 2, in step S17, the image capturing device 13 can be controlled by the computer 17 to capture the first layer cross-sectional view of the printed particles (i.e., the target object), so that the modulated femtosecond laser beam forms a parallel beam arranged according to the first layer cross-sectional view.

[0058] Referring to Figure 2, in step S19, a parallel beam of light is focused on the photosensitive material 15 through the focusing lens 14 to form a planar pattern composed of multiple focal points, wherein the photosensitive material at all focal points is solidified, thereby realizing a one-time projection to form a first-layer cross-sectional structure for printing the first layer cross-sectional pattern of the particles.

[0059] Referring to Figure 2, in step S21, the computer 17 can control the displacement platform 16 to move a distance equal to the thickness of a layer of the printed particles. The direction of movement of the displacement platform is parallel to the direction of the femtosecond laser beam irradiating the photosensitive material.

[0060] Referring to Figure 2, in step S23, the image capturing device 13 can be controlled by the computer 17 to capture cross-sectional views of each subsequent layer of the printed particles layer by layer.

[0061] Referring to Figure 2, in step S25, after forming each subsequent layer cross-sectional view of the printed particles, the displacement platform 16 can be moved a distance by the computer 17, the distance being equal to the thickness of one layer cross-section of the printed particles, until the printed particles are formed.

[0062] In some embodiments, the polishing composition may substantially include any suitable amount of the above-described (colloidal) printed particles. For example, when used, the polishing composition may include about 0.01 wt% or more of printed particles (e.g., about 0.05 wt% or more, about 0.1 wt% or more, about 0.2 wt% or more, about 0.3 wt% or more, about 0.4 wt% or more, or about 0.5 wt% or more). When used, the amount of printed particles in the polishing composition may include about 20 wt% or less (e.g., about 20 wt% or less, about 5 wt% or less, or about 3 wt% or less, about 2 wt% or less, or even about 1 wt% or less). Therefore, it should be understood that, in use, the content of printed particles may be in the range defined by any of the two endpoints above, for example, from about 0.01 wt% to about 20 wt% (e.g., from about 0.1 wt% to about 10 wt%, from about 0.1 wt% to about 5 wt%, from about 0.1 wt% to about 3 wt%, or from about 0.2 wt% to about 3 wt%).

[0063] Liquid carriers are generally used to facilitate the application of abrasives (printing particles) and any optional chemical additives to the surface of a substrate to be polished (e.g., planarized). The liquid carrier can be any suitable carrier (e.g., solvent), including lower alcohols (e.g., methanol, ethanol, etc.), ethers (e.g., dioxane, tetrahydrofuran, etc.), water, and mixtures thereof. In some embodiments, the liquid carrier comprises, essentially comprises, or consists of water, more preferably comprises, essentially comprises, or consists of deionized water.

[0064] In some embodiments, the printed particles may have a positive charge in the polishing composition (e.g., in a liquid carrier). The charge on the printed particles is generally referred to as zeta potential or electrokinetic potential. The zeta potential of a particle is the potential difference between the charge of the ions surrounding the particle and the charge of the bulk solution of the polishing composition (e.g., the liquid carrier and any other components dissolved therein).

[0065] In some embodiments, the printed particles in the polishing composition may have a positive charge of about 10 mV or more (e.g., about 15 mV or more, about 20 mV or more, or about 25 mV or more). In some embodiments, the printed particles in the polishing composition may have a positive charge of about 60 mV or less (e.g., about 55 mV or less or about 50 mV or less). Therefore, it should be understood that the printed particles may have a positive charge in the polishing composition within a range defined by any of the above endpoints, for example, from about 10 mV to about 60 mV (e.g., about 15 mV to about 60 mV, or about 25 mV to about 50 mV).

[0066] While this disclosure is not limited in this respect, the printed particles may advantageously possess a permanent positive charge. A permanent positive charge means that the positive charge on the printed particles is not easily reversed, for example, by rinsing, dilution, filtration, or similar methods. A permanent positive charge may be the result of a covalent bond between the cationic compound and the printed particles. A permanent positive charge is the opposite of a reversible positive charge, which may be the result of an electrostatic interaction between the cationic compound and the printed particles.

[0067] In some embodiments, the printed particles may selectively possess a non-permanent positive charge, for example, through contact with a cationic component (i.e., a positively charged substance) in a liquid carrier. The non-permanent positive charge may be achieved, for example, by treating the printed particles with at least one cationic component selected from, for example, ammonium salts (preferably quaternary amine compounds), phosphate salts, strontium salts, imidazole salts, and pyridine salts.

[0068] In some embodiments, depending on the intended application, the grinding composition may have virtually any suitable pH. In other words, the grinding composition may be acidic, neutral, or alkaline. Partly to minimize safety and transport issues, the pH is generally in the range of about 2 to about 12 (e.g., from about 2 to about 6, from about 5 to about 9, or from about 8 to about 12). In some embodiments, the pH of the grinding composition may be in the range of about 1 to about 6 (e.g., from about 1 to about 5, from about 2 to about 5, or from about 2 to about 4).

[0069] The pH of the grinding composition can be achieved and / or maintained by any suitable means. The grinding composition may substantially include any suitable pH adjuster or buffer system. For example, suitable pH adjusters may include nitric acid, sulfuric acid, phosphoric acid, phthalic acid, citric acid, adipic acid, oxalic acid, malonic acid, maleic acid, ammonium hydroxide, or the like, while suitable buffers may include phosphates, sulfates, acetates, malonates, oxalates, borates, ammonium salts, or the like.

[0070] In some embodiments, the polishing composition may substantially include any suitable chemical additive. In some embodiments, the polishing composition configured for polishing a metal layer may include one or more of the following components: oxidizing agents, chelating agents, polishing rate accelerators, catalysts, polishing rate inhibitors, morphology control agents, etching inhibitors, pH buffers, dispersants, and biocides. In some embodiments, the polishing composition configured for polishing a dielectric layer may include one or more of the following components: cationic, anionic, or nonionic polymers, secondary polishing rate accelerators or inhibitors (e.g., for nitride layers), dispersants, regulators, scale inhibitors, chelating agents, stabilizers, pH buffers, and biocides. These additives are entirely optional. The disclosed embodiments are not limited thereto and do not require the use of any one or more of these additives.

[0071] In some embodiments, the polishing composition may include an oxidizing agent. The oxidizing agent may be added to the polishing composition during the slurry preparation process or prior to CMP operation (e.g., in a tank located in a semiconductor fabrication facility). In some embodiments, the oxidizing agent may include an inorganic or organic peroxide compound. A peroxide compound as defined herein is a compound containing at least one peroxy group (-OO-) or a compound containing an element in its highest oxidation state. Examples of compounds containing at least one peroxy group include, but are not limited to, hydrogen peroxide and its adducts, such as urea hydrogen peroxide and percarbonate; organic peroxides, such as benzoyl peroxide, peracetic acid, and di-t-butyl peroxide; monopersulfate (SO₅⁻); dipersulfate (S₂O₈⁻); and sodium peroxide. Examples of compounds containing an element in its highest oxidation state include, but are not limited to, periodic acid, periodate, perbromic acid, perbromate, perchloric acid, perchlorate, perboric acid, perborate, and permanganate. The most preferred oxidizing agent is hydrogen peroxide.

[0072] In some embodiments, the oxidant present in the grinding composition during use may be in the range of, for example, about 0.1 to about 20 wt%. For example, in embodiments using hydrogen peroxide and a soluble accelerator, the oxidant present in the grinding composition during use may be in the range of, for example, about 0.1 wt% to about 10 wt% (e.g., from about 1 wt% to about 10 wt%, from about 1 wt% to about 5 wt%).

[0073] In some embodiments, the grinding composition may include an inhibitor. In some embodiments, the inhibitor includes compounds having a nitrogen-containing functional group, such as nitrogen-containing heterocycles, alkylammonium ions, aminoalkyl groups, and amino acids. Useful aminoalkyl corrosion inhibitors include, for example, hexylamine, tetramethyl-p-phenylene diamine, octylamine, diethylene triamine, dibutyl benzylamine, aminopropylsilanol, aminopropylsiloxane, dodecylamine, mixtures thereof, and synthetic and naturally occurring amino acids, including, for example, lysine, tyrosine, glutamine, glutamic acid, cystine, and glycine (aminoacetic acid).

[0074] In some embodiments, the inhibitor compound may alternatively and / or additionally include an amine compound dissolved in a liquid carrier. The amine compound (or compound) may include primary, secondary, tertiary, or quaternary amines. The amine compound may further include monoamines, diamines, triamines, tetraamines, or amine polymers having a large number of repeating amine groups (e.g., four or more amine groups).

[0075] In some embodiments, the inhibitor compound may further comprise a cationic polymer. Examples of cationic polymers include, but are not limited to: poly(vinylimidazolium), poly(methacryloyloxyethyltrimethylammonium) chloride (polyMADQUAT), poly(diallyldimethylammonium) chloride (polyDADMAC) (i.e., polyquaternary ammonium salt-6), poly(dimethylamine-co-epichlorohydrin), and poly[bis(2-chloroethyl) ether-alt-1,3-bis[3-(dimethylamino)propyl]urea] (i.e., polyquaternary ammonium salt-2), copolymer of hydroxyethyl cellulose and diallyl dimethyl ammonium (i.e., polyquaternary ammonium salt-4), copolymer of acrylamide and diallyl dimethyl ammonium (i.e., polyquaternary ammonium salt-7), quaternary ammonium hydroxyethyl cellulose ethoxylate (i.e., polyquaternary ammonium salt-10), copolymer of vinylpyrrolidone and quaternary ammonium dimethylaminoethyl methacrylate (i.e., polyquaternary ammonium salt-11), vinylpyrrolidone and quaternary ammonium vinylimidazole (i.e., polyquaternary ammonium salt-16), polyquaternary ammonium salt-24, terpolymer of vinylcaprolactone, vinylpyrrolidone, and quaternary ammonium vinylimidazole (i.e., polyquaternary ammonium salt-46), 3-methyl-1-vinylimidazole methyl sulfate-N-vinylpyrrolidone copolymer (i.e., polyquaternary ammonium salt-44), and copolymer of vinylpyrrolidone and diallyl dimethyl ammonium.

[0076] In some embodiments, the inhibitor compound may comprise a cationic polymer having an amino acid monomer (such compounds may also be referred to as polyamino acid compounds). In some embodiments, the polyamino acid compound may substantially comprise any suitable amino acid monomer group, for example, including polyarginine, polyhistamine, polyalanine, polyglycine, polytyrosine, polyproline, and polylysine. In some embodiments, polylysine is a preferred polyamino acid. It should be understood that polylysine may comprise ε-polylysine and / or α-polylysine composed of D-lysine and / or L-lysine. Therefore, polylysine may comprise α-poly-L-lysine, α-poly-D-lysine, ε-poly-L-lysine, ε-poly-D-lysine, and mixtures thereof. It should be further understood that polyamino acid compounds (or compounds) can be used in any available form. For example, the conjugate acid or base and salt form of polyamino acid can be used instead of polyamino acid, or the conjugate acid or base and salt form of polyamino acid can be used in addition to polyamino acid.

[0077] In some embodiments, the polishing composition may substantially include any suitable concentration of an inhibitor compound. Generally, the ideal concentration is preferably high enough to provide adequate etch inhibition, but low enough to allow the compound to dissolve without reducing the polishing rate below an acceptable level. Solubility means that the compound is completely dissolved in the liquid carrier, or forms microcells in the liquid carrier or is carried within microcells. The concentration of the inhibitor compound may need to be varied depending on various factors, including its solubility, the number of amine groups therein, the length of the alkyl group, the relationship between etch rate inhibition and polishing rate inhibition, the oxidant used, the concentration of the oxidant, etc. In some ideal embodiments, the concentration of the amine compound in the polishing composition may be in the range of about 0.1 μM to about 10 mM (i.e., from about 10⁻⁷ to about 10⁻² moles). For example, in embodiments using polymer inhibitors (such as cationic polymers), the concentration may be at the lower end of this range (e.g., about 10⁻⁷ to about 10⁻⁴ moles when used). In other embodiments using non-polymeric compounds (with fewer cationic groups and lower molecular weight), the concentration can be at the higher end of this range (e.g., approximately 10⁻⁵ to approximately 10⁻² mol when used).

[0078] In some embodiments, the grinding composition may include a biocide. The biocide may include any suitable biocide, such as an isothiazolinone biocide. When used or in a concentrate, the biocide content in the grinding composition is typically in the range of about 1 ppm to about 50 ppm, and preferably from about 1 ppm to about 20 ppm.

[0079] In some embodiments, the milling composition may be prepared by combining its components in any order. The term "component" as used herein includes individual ingredients (e.g., printing particles, accelerators, amine compounds, etc.).

[0080] In some embodiments, the polishing composition components (such as accelerators, stabilizers, etching inhibitors, and / or biocides) can be added directly to the printed particles dispersed in a liquid carrier. In some embodiments, multiple batches of printed particles (e.g., first printed particles and second printed particles) with different physical properties (e.g., shape, size, surface charge, etc.) can be prepared separately. The first and second printed particles can be mixed together before adding other polishing composition components. In some embodiments, other components can be added to one of the printed particles before mixing the first and second printed particles together. Any suitable technique can be used to mix the printed particles and other components to achieve thorough mixing. An optional oxidant can be added at any point during the preparation of the polishing composition. For example, the polishing composition can be prepared before use and one or more of the components (such as an oxidant) can be added before the CMP operation (e.g., within about 1 minute, about 10 minutes, about 1 hour, or about 1 day, or about 1 week of the CMP operation). The polishing composition can also be prepared during the CMP operation by mixing the components on the surface of a substrate (e.g., on a polishing pad).

[0081] In some embodiments, the polishing composition may also be provided as a concentrate intended to be diluted with an appropriate amount of water before use. In some embodiments, the polishing composition concentrate may include printing particles, water, and other optional components (such as accelerators, stabilizers, etching inhibitors, and biocides), with or without an oxidant, in an amount such that after diluting the concentrate with an appropriate amount of water and an optional oxidant (if not already present in an appropriate amount), each component of the polishing composition will be present in the polishing composition in an amount within the appropriate range described above for each component. For example, the amount of printing particles and other optional components in the polishing composition may each be approximately twice the concentration of each of the above-described components at the time of use (e.g., approximately three times, approximately four times, approximately five times, or even approximately ten times), so that when the concentrate is diluted with an appropriate amount of oxidant with equal volumes of water (e.g., 2 equal volumes of water, 3 equal volumes of water, 4 equal volumes of water, or even 9 equal volumes of water respectively), the amount of each component in the polishing composition is within the range described above for each component. In some embodiments, the concentrate may contain an appropriate proportion of water present in the final milled composition to ensure that other components are at least partially or completely dissolved in the concentrate.

[0082] In some embodiments, the abrasive composition can be used substantially to abrade any substrate, including dielectric layers and / or metal layers such as tungsten, copper, aluminum, cobalt, and / or barrier layers such as titanium, titanium nitride, tantalum, and / or tantalum nitride.

[0083] One aspect of this disclosure provides a grinding composition comprising a liquid carrier and a plurality of printed particles dispersed in the liquid carrier. The printed particles are prepared by a lamination process.

[0084] Another aspect of this disclosure provides a polishing composition comprising a liquid carrier; a plurality of first printed particles dispersed in the liquid carrier; and a plurality of second printed particles dispersed in the liquid carrier. The first printed particles and the second printed particles are prepared by a lamination process. The size of the first printed particles and the size of the second printed particles are different.

[0085] Another aspect of this disclosure provides a method for preparing printed particles, comprising: preparing a photosensitive material and placing the photosensitive material on a displacement platform; activating a femtosecond laser to generate a plurality of femtosecond laser beams; modulating the femtosecond laser beams using an external path modulation unit; using a computer-controlled image capturing device to capture a first layer profile of the plurality of printed particles, such that the modulated femtosecond laser beams form a plurality of parallel beams arranged according to the first layer profile; focusing the parallel beams through a plurality of focusing lenses in the photosensitive material to form a planar image composed of multiple focal points, wherein the photosensitive material at all focal points is cured, thereby realizing the formation of the printed particles. The first layer cross-sectional view of the particles is projected in a single step; the computer is used to control the displacement platform to move a distance equal to the thickness of one layer of the printed particles, and the direction of movement of the displacement platform is parallel to the direction in which the femtosecond laser beams irradiate the photosensitive material; the computer controls the image capturing device to capture cross-sectional views of subsequent layers of the printed particles via laser; after forming a subsequent layer cross-sectional view of the printed particles, the computer is used to control the displacement platform to move a distance equal to the thickness of one layer of the printed particles until the printed particles are formed.

[0086] Because the structural differences (e.g., shape, size, surface charge) between individual particles of the printed particles formed through the lamination process are small, batch-to-batch variability in CMP operations using this polishing composition can be reduced. As a result, process stability of the CMP operation can be improved and process control simplified. Furthermore, the shape, size, surface charge, polarity, and size distribution of the printed particles can be customized through the lamination process to meet the requirements of various processes.

[0087] Although the present disclosure and its advantages have been described in detail, it should be understood that various changes, substitutions and alternatives can be made without departing from the spirit and scope of the present disclosure as defined in the claims. For example, many of the above-described processes can be implemented using different methods, and many of the above-described processes can be replaced by other processes or combinations thereof.

[0088] Furthermore, the scope of this application is not limited to the specific embodiments of the processes, machinery, manufacturing, material composition, means, methods, and steps described in the specification. Those skilled in the art can understand from the disclosure herein that existing or future processes, machinery, manufacturing, material composition, means, methods, or steps that have the same function or achieve substantially the same results as the corresponding embodiments described herein can be used based on this disclosure. Therefore, such processes, machinery, manufacturing, material composition, means, methods, or steps are included within the scope of the patent application of this application. [Simplified Explanation of the Diagram]

[0010] A more complete understanding of this disclosure can be obtained by referring to the detailed description and the claims when considering the figures, wherein similar reference numerals represent similar elements in the overall figures, and: Figure 1 shows a schematic diagram of the system structure for preparing printed particles using two-photon polymerization with the femtosecond laser disclosed herein. Figure 2 shows a flowchart of the method for preparing printed particles using two-photon polymerization with the femtosecond laser disclosed herein.

Claims

1. A method for preparing printing particles for use in a grinding composition, comprising: Provide a liquid carrier; And a plurality of printed particles having colloidal nanoparticles of alumina, cerium oxide, or a combination thereof prepared by a lamination process, wherein the printed particles are dispersed in the liquid carrier, wherein the mass percentage concentration of the printed particles in the polishing composition is between 0.01 wt% and 20 wt%, wherein the lamination process is two-photon polymerization using a femtosecond laser.

2. The preparation method as described in claim 1, wherein the size of the printed particles is between about 20 nm and about 200 nm.

3. The preparation method as described in claim 1, wherein a standard deviation of a size of the printed particles is between about 1 nm and about 10 nm.

4. The preparation method as described in claim 1, wherein the printed particles are spherical, elliptical, rhombohedral, tetrahedral, cubic, or cuboid in shape.

5. The preparation method as described in claim 1, wherein the liquid carrier comprises a lower alcohol, ether, water, or a mixture thereof.

6. The preparation method as described in claim 1, wherein the printed particles have a positive charge of at least 10 mV in the liquid carrier.

7. The preparation method as described in claim 1, wherein the pH of the milling composition is between about 2 and about 12.

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