Chemical mechanical planarization slurry processing techniques and systems and methods for polishing substrate using the same

Abstract

A chemical mechanical planarization (CMP) system, apparatus, and method, the method comprising: providing a CMP slurry source; modifying the CMP slurry source by directing a source of at least one of mechanical or electromagnetic energy toward the CMP slurry source to form a modified CMP slurry; applying a fluid of the modified CMP slurry to a wafer polishing apparatus, a substrate being positioned at the wafer polishing apparatus; and performing a polishing operation on the substrate.

Description

Technical Field

[0001] This disclosure generally relates to chemical mechanical planarization (CMP) for semiconductor manufacturing processes. More specifically, this disclosure relates to the enhancement of paste formulations and equipment and processes for polishing substrates such as semiconductor wafers. Prior Technology

[0002] Chemical mechanical planarization (CMP) is a part of semiconductor manufacturing processes that remove materials from a substrate (e.g., a wafer) and planarize metal, polysilicon, and / or dielectric layers during integrated circuit (IC) manufacturing. CMP performs a chemical reaction followed by mechanical force generated by abrasive particles to remove metal deposits or similar materials forming these layers.

[0003] CMP processes typically involve the use of a slurry application system, which includes equipment that outputs a slurry source to a polishing pad to apply a combination of chemicals and abrasive particles to a rotating substrate polisher positioned on the wafer. Without a suitable system, the type and characteristics of the slurry material, as well as the method of application, can result in lower material removal rates, greater than required slurry consumption, undesirable surface scratches, or other defects on the wafer. Summary of the Invention

[0004] In one embodiment, the present invention provides a chemical mechanical planarization (CMP) method, the method comprising: providing a CMP slurry source; modifying the CMP slurry source by directing a source of at least one of mechanical or electromagnetic energy toward the CMP slurry source to form a modified CMP slurry; applying a fluid of the modified CMP slurry to a wafer polishing apparatus, a substrate being positioned at the wafer polishing apparatus; and performing a polishing operation on the substrate.

[0005] In some embodiments, the CMP method further includes modifying the CMP slurry source by applying a material additive to the CMP slurry source.

[0006] In some embodiments, the material additive is applied to the CMP slurry source before the source of at least one of mechanical or electromagnetic wave energy is directed to the CMP slurry source.

[0007] In some embodiments, when the source of at least one of mechanical or electromagnetic energy is directed to the CMP slurry source, the material additive is simultaneously applied to the CMP slurry source.

[0008] In some embodiments, the CMP slurry source is modified by directing the source of at least one of mechanical or electromagnetic energy to the CMP slurry source at the wafer polishing apparatus and by applying the material additive to the CMP slurry source at the wafer polishing apparatus.

[0009] In some embodiments, the additive is modified by at least one of mechanical or electromagnetic wave energy.

[0010] In some embodiments, the CMP slurry source is modified by the mechanical energy source within a sealed container, and the application of the fluid of the modified CMP slurry to the wafer polishing apparatus includes outputting the modified CMP slurry from the sealed container to the wafer polishing apparatus.

[0011] In some embodiments, the sealed container includes: a container housing having an opening leading to an interior of the container housing, the interior being constructed and configured to hold the CMP slurry source; a cap sealing system forming a fluid seal over the opening of the container housing; and an inlet and an outlet extending through the cap sealing system to form a continuous slurry flow path from the inlet through the interior of the container housing and further from the outlet to a wafer polishing apparatus.

[0012] In some embodiments, the mechanical wave energy is acoustic energy generated inside the sealed container.

[0013] In some embodiments, the electromagnetic wave energy is light generated along the fluid of the CMP slurry between the sealed container and the wafer polishing equipment.

[0014] In some embodiments, the mechanical wave energy is the acoustic energy applied to the fluid of the CMP slurry after the light is applied to the fluid.

[0015] In some embodiments, the mechanical wave energy is the acoustic energy applied to the fluid of the CMP slurry before the light is applied to the fluid.

[0016] In some embodiments, the source of at least one of mechanical or electromagnetic wave energy includes both acoustic energy and light, wherein the acoustic energy is directed to the CMP slurry source before the light is directed to the CMP slurry source.

[0017] In some embodiments, the source of at least one of mechanical or electromagnetic energy includes both acoustic energy and light energy applied simultaneously to the CMP slurry source.

[0018] In some embodiments, the source of at least one of mechanical or electromagnetic wave energy includes both acoustic energy and light, and wherein the acoustic energy is directed to the CMP slurry source after the light is directed to the CMP slurry source.

[0019] In another embodiment, the present invention provides a slurry processing system comprising: a container housing having an opening leading to an interior of the container housing configured and configured to hold a chemical mechanical planarization (CMP) slurry source; a cap sealing system forming a fluid seal over the opening of the container housing; an inlet and an outlet extending through the cap sealing system to form a continuous slurry flow path from the inlet through the interior of the container housing and further from the outlet to a wafer polishing apparatus; and an energy generating device directing a source of at least one of mechanical or electromagnetic energy toward the CMP slurry flowing along the continuous slurry flow path.

[0020] In some embodiments, the cap sealing system includes: a retaining ring element through which the inlet and the outlet extend; a shear ring positioned in a groove around the container housing, the shear ring forming a seal-tight interface with the retaining ring element; and a sliding fit element forming a seal-tight interface with the retaining ring element.

[0021] In some embodiments, the sliding engagement element includes a first clamping portion and a second clamping portion, wherein at least one of the first clamping portion and the second clamping portion includes a rod configured for insertion into a hole in the other of the first clamping portion and the second clamping portion, and wherein the cap sealing system includes a wing nut positioned around the rod in the hole to generate a force that couples the first clamping portion and the second clamping portion together around the retaining ring element and coupled around the shear ring of the container housing.

[0022] In some embodiments, the slurry handling system further includes a vent pipe coexisting with the inlet and the outlet, the vent pipe extending through the cap sealing system to allow trapped air to escape from the container housing.

[0023] In some embodiments, the slurry processing system further includes a gas inlet pipe for injecting or impregnating oxygen or ozone.

[0024] In some embodiments, the sliding fit element has a hemispherical interior formed by the first portion and the second portion, the hemispherical interior being threaded to form a seal when coupled with the retaining ring element.

[0025] In some embodiments, the CMP slurry is configured to be chemically connected to one of the substrates on the wafer polishing apparatus, one of the upper layers of which is formed of copper, tungsten, polysilicon, silicon dioxide, aluminum, carbon-doped silicon dioxide, black diamond, silicon nitride, tantalum, tantalum nitride, titanium, titanium nitride, cobalt, gallium nitride, ruthenium, silicon carbide, or combinations thereof or alloys thereof.

[0026] In some embodiments, the energy generating device includes a sound wave generating mechanism that also has a transducer or similar, which generates sound energy to acoustically activate the CMP slurry along the continuous slurry flow path.

[0027] In some embodiments, the energy generating device includes a light source configured and arranged to irradiate the CMP slurry.

[0028] In some embodiments, the CMP slurry includes at least one ligand ligand and a metal oxide to form a metal-ligand complex irradiated by the light source to oxidize the ligand.

[0029] In some embodiments, the ligand miscible agent includes at least one of tyrosine, phenylalanine, tryptophan, histidine, and glycine.

[0030] In some embodiments, the CMP slurry comprises a polymer-based nanocomposite slurry, which includes a macromolecular polymer and a composite additive.

[0031] In some embodiments, the energy generating device includes a first device employing megasonic energy and a second device employing light waves, the first device and the second device being directed to the CMP slurry in chemical contact with a SiC substrate to remove a surface layer of the SiC substrate during a polishing operation performed by the wafer polishing equipment.

[0032] In another embodiment, the present invention provides a chemical mechanical planarization (CMP) method comprising: providing a CMP slurry source; modifying the CMP slurry source by directing an acoustic energy source toward the CMP slurry source to form a modified CMP slurry; applying a fluid of the modified CMP slurry to a wafer polishing apparatus, wherein a substrate is positioned at the wafer polishing apparatus; and performing a polishing operation on the substrate.

[0033] In another embodiment, the present invention provides a chemical mechanical planarization (CMP) method comprising: providing a CMP slurry source; modifying the CMP slurry source by directing a light source toward the CMP slurry source to form a modified CMP slurry; applying a fluid of the modified CMP slurry to a wafer polishing apparatus, wherein a substrate is positioned at the wafer polishing apparatus; and performing a polishing operation on the substrate.

[0034] Additional advantages and novel features will be partly set forth in the following description, and some will become apparent to those skilled in the art upon studying the following text and figures, or may be learned by the generation or operation of examples. The advantages of this teaching can be realized and accomplished through the practice or use of various forms of methods, mechanisms, and combinations described in the detailed examples discussed below.

[0035] Cross-referencing of related applications: This application claims U.S. Provisional Patent Application No. 63 / 149,733, filed February 16, 2021, entitled "SONICATED CHEMICAL-MECHANICAL PLANARIZATION (CMP)"; U.S. Provisional Patent Application No. 63 / 150,683, filed February 18, 2021, entitled "LIGHT ENHANCED CHEMICAL-MECHANICAL PLANARIZATION (CMP)"; U.S. Provisional Patent Application No. 63 / 165,444, filed March 24, 2021, entitled "SLURRY INJECTION SYSTEM WITH SIDE CAR AND END-EFFECTORS"; and U.S. Provisional Patent Application No. 63 / 165,444, filed March 10, 2021, entitled "REAL-TIME PAD-LEVEL SLURRY EFFLUENT EXTRACTION SYSTEM FOR CMP". The interests and priorities of U.S. Provisional Patent Application No. 63 / 186,343, filed May 13, 2021, entitled "SILICON CARBIDE (SIC) WAFER POLISHING WITH NOVEL SLURRY FORMULATIONS AND PROCESSES", U.S. Provisional Patent Application No. 63 / 188,305, filed June 16, 2021, entitled "DEVICE FOR ENABLING DIRECT AND CONTINUOUS CMP OR POLISHING SLURRY SONICATION", are hereby referred to in their entirety. This application relates to U.S. Patent Nos. 8,197,306, 8,845,395, 9,296,088, Korean Patent No. 1,394,745, Japanese Patent No. 5,574,597, and Taiwan Patent No. 1,486,233, the entire contents of which are incorporated herein by reference. Simple Explanation of the Diagram

[0036] The diagrams depict one or more embodiments according to this teaching by way of example rather than limitation. In the diagrams, similar reference numerals indicate the same or similar elements. [Figure 1] is a diagram illustrating the components of a CMP slurry processing system according to some embodiments. [Figure 2A] is a flowchart of the CMP method according to some embodiments. [Figure 2B] is a flowchart of the CMP method according to other embodiments. [Figure 2C] is a flowchart of the CMP method according to other embodiments. [Figure 2D] is a flowchart of the CMP method according to other embodiments. [Figure 2E] is a flowchart of the CMP method according to other embodiments. [Figure 3] is a schematic diagram of a CMP slurry treatment system according to some embodiments. [Figure 4] is a perspective view of a slurry processing system according to some embodiments. [Figure 4A] is a top view of the slurry processing system in Figure 4. [Figure 4B] is a top view of the slurry processing system of Figure 4, showing the interior of the container shell after the cap sealing system has been removed from the container shell. [Figure 5] is a front cross-sectional view of the slurry treatment system in Figure 4. [Figure 6] is an exploded view of the slurry processing system shown in Figures 4 and 5. [Figure 6A] is an enlarged cross-sectional front view of the sealing area of ​​the slurry treatment system shown in Figures 4 to 6. [Figure 7] is a bar graph showing the comparative material removal rates from different CMP processes that use slurry. [Figure 8] is a diagram illustrating the operation of a slurry injection system combined with a slurry processing system according to some embodiments. [Figure 9A] is a flowchart illustrating the operation of the light generation system of a slurry processing system according to some embodiments. [Figure 9B] is a flowchart illustrating the operation of the light generation system of the slurry processing system according to other embodiments. [Figure 9C] is a flowchart illustrating the operation of a slurry processing system according to other embodiments. Implementation

[0037] In the following embodiments, numerous specific details are presented by way of example to provide a thorough understanding of the relevant teachings. However, it will be apparent to those skilled in the art that the teachings can be practiced without such details. In other instances, well-known methods, procedures, components, and / or circuit systems have been described in a relatively high-level manner without detail to avoid unnecessarily obscuring the nature of the teachings.

[0038] Figure 1 is a block diagram of a slurry processing system 10 for a CMP process according to some embodiments. The slurry processing system 10 is constructed and configured to provide a slurry source, which is either a raw source of slurry 17 stored in a slurry holding container 114 (shown in Figure 2A) or modified slurry 17A enhanced or modified by one or more material additives 131 (shown in Figure 1), such as chemical additives. In some embodiments, for example after being discharged from the slurry holding container 114 and received by the slurry application system 110 to a wafer polishing apparatus 102, the modified slurry 17A is alternatively or additionally enhanced or modified by a source of mechanical and / or electromagnetic energy. The wafer polishing apparatus includes a polishing head 104 of a wafer 20 rotating on a polishing pad 103 of the apparatus 102. The polishing pad 103 may be a polyurethane-based pad with concentric trenches or XY trenches, or have another pad configuration or construction material. The CMP wafer or substrate polishing system 102 may include other well-known components, such as motors (e.g., servo motors and / or variable frequency motors), electronics, actuators, wafer carriers, robots and wafer handling components, temperature sensors, holding rings, shear and normal force transducers, IR detectors, etc., but these are not shown for simplicity. In some embodiments, the wafer carrier provides an average pressure in the range of 0.6 to 8 PSI and rotates from 15 to 200 RPM, but is not limited thereto. The top layer of the substrate 20 for polishing may be formed of one or more materials, such as copper, tungsten, aluminum, polycrystalline silicon, silicon dioxide, carbon-doped silicon dioxide, black diamond, silicon nitride, tantalum, tantalum nitride, titanium, titanium nitride, cobalt, gallium nitride, ruthenium, silicon carbide, or combinations thereof or alloys thereof, for shallow trench isolation (STI) CMP applications that require the use of slurry, for example, which may chemically react with the materials(s) forming the substrate 20. In some embodiments, the substrate 20 has a wafer size of 200 mm or 300 mm, but is not limited thereto. The source of the original paste 17 or modified paste 17A is delivered to the polishing pad 103 via the paste application system 110. As described above, the paste 17 displayed on the polishing pad 103 can be one of the sources of off-the-shelf or undoped paste 17, or in other embodiments, it can be modified by material additive 131, referred to as modified paste 17A.

[0039] In some embodiments, the slurry application system 110 includes one or more slurry holding containers 114, one or more additive holding devices 116, a wave energy source 133, and a slurry application system 110.

[0040] Multiple slurry holding containers 114 and / or multiple additive holding devices 116 may be storage tanks and other chemical additive delivery mechanisms, baffles, level sensors, chemical sensors, pumps, agitators, filters, onboard computers and controllers, flow meters, etc. In some embodiments, slurry holding containers 114 may be 20-liter tanks including the mixers, pumps, and sensors described herein. These elements of the slurry dispensing system 110 may control the source of slurry 17, for example, by agitation, blending, filtration, circulation, or otherwise dispensing slurry 17. In some embodiments, as illustrated in the examples herein, the slurry dispensing system 110 provides flow rates in the range of 10 to 500 cc / min, but is not limited thereto.

[0041] In some embodiments, wave energy source 133 includes a sound wave generating mechanism having one or more transducers or the like (not shown) that generates mechanical waves (e.g., sound waves), cavitation, vibration, and the like to acoustically activate slurry liquid in the storage area of ​​slurry application system 110. In some embodiments, the sound wave generating mechanism may direct acoustic energy in megaphone, ultrasonic, or related acoustic spectra. Applying slurry to the substrate surface allows a passivation layer (which is continuously polished) at the top of the substrate surface to become softer and less dense through a chemical reaction with the slurry, and this passivation layer can be enhanced by acoustic treatment of the slurry. Under this approach, compared to acoustic treatment without sonication, during the acoustic treatment prior to applying the slurry to the polishing pad 103, the removal rate (RR) and / or other removal characteristics are higher for films made of copper, tungsten, polycrystalline silicon, aluminum, silicon dioxide, carbon-doped silicon dioxide, black diamond, silicon nitride, tantalum, tantalum nitride, titanium, titanium nitride, cobalt, gallium nitride, ruthenium, silicon carbide, or combinations thereof or alloys thereof, in response to the sonic treatment energy applied to the slurry. Furthermore, when reaching films made of copper, tungsten, polycrystalline silicon, silicon dioxide, aluminum, carbon-doped silicon dioxide, black diamond, silicon nitride, tantalum, tantalum nitride, titanium, titanium nitride, cobalt, gallium nitride, ruthenium, silicon carbide, or combinations thereof or alloys thereof, the softened passivation layer formed by the aforementioned electromagnetically activated chemical reaction results in lower wafer-level defects and better polished surface quality. A higher material removal rate is preferable because it is inversely proportional to polishing time. Therefore, the productivity of CMP modules in integrated circuit manufacturing plants increases because wafer yield is higher with shorter production times. Furthermore, the shorter polishing time means less paste is needed to polish wafers via the CMP process. This results in a cost advantage, as paste is the most expensive consumable in CMP modules. Moreover, this is a positive step towards environmentally conscious manufacturing, as paste poses environmental hazards, and its disposal and legal disposal are costly. Additionally, achieving lower wafer-level defects is preferable because excessive defects reduce product yield. Therefore, any reduction in defect levels and the surface finish of the polished material are ways to improve productivity.

[0042] In some embodiments, the wave energy source 133 of the CMP slurry processing system 10 includes an electromagnetic wave source (e.g., a light wave energy source, as shown in Figures 9A-9C) configured and positioned to irradiate the source of slurry 17. In some embodiments, the modified slurry 17A includes a material additive to induce ligand-to-metal-charge-transfer (LMCT) after irradiation by the light wave energy source 112 (see Figures 9A-9C) of the wave energy source 133, to produce a photosensitive slurry for CMP operation. For example, by modulating the wavelength or intensity of electromagnetic radiation by the light wave energy source 112, we can modulate the removal rate and other process performance parameters at the wafer level. The wavelength of light can range from 200 to 800 nm, but is not limited thereto. In some embodiments, one of the light wave energy sources of the wave energy source 133 (shown in Figure 1) is positioned close to the polishing pad 103 to irradiate the slurry before it is applied to the top of the polishing pad 103. In these similar embodiments, one of the sound sources of wave energy source 133 (not shown in FIG1) is a component or additional part of the slurry application system shown, for example, in FIG3 to FIG6.

[0043] The slurry processing system 10 may include a data analysis and reporting computer 12 that communicates with the wafer polishing equipment 102 and the slurry dispensing system 110 via a special purpose processor 120. The processor 120 may communicate with a controller 122 to manage and control the operation of the polisher and injector.

[0044] Figure 2A is a flowchart of a CMP method according to some embodiments. In some embodiments, method 200 may include some or all of the elements of the CMP slurry processing system 10 of Figure 1.

[0045] Method 200 may begin at step 202, wherein one source of slurry 17 is modified to form a modified slurry 17A, the modified slurry comprising one or more material additives 131, such as chemical additives. In other embodiments, the slurry is unmodified, for example, off-the-shelf or other commercially available slurry 17. Material additives 131 may be selected based on their functionality, such as those described in the examples below. In other embodiments, other slurry additives may modify the liquid surface tension and the contact angle with the substrate, such as those described in the examples below.

[0046] In step 204, a mechanical (e.g., acoustic) and / or electromagnetic (e.g., optical) source is applied to the modified slurry 17A. In some embodiments, method 200 does not include step 202 and proceeds directly to step 204, wherein the off-the-shelf or unmodified slurry 17 does not include additive 131. In some embodiments, prior to application to the polishing pad 103 in step 206, the slurry may flow through a mega-sonication treatment and / or a light enhancement process performed by a light energy source 133 as part of a CMP process or the like. In some embodiments, a photosensitivity-enhancing material is added to the slurry to increase the material removal rate when the slurry is excited by one of the light energy sources of the light energy source 133. In some embodiments, in addition to or instead of the material additive of step 202, an additive comprising a photosensitizing compound medium is added. In some embodiments, the wave energy source 133 may be operated in conjunction with, for example, the slurry injection system shown in FIG8, and / or the slurry injection system described in one or more of the following patents: U.S. Patent No. 8,197,306, U.S. Patent No. 8,845,395, U.S. Patent No. 9,296,088, Korean Patent No. 1,394,745, Japanese Patent No. 5,574,597, and Taiwan Patent No. 1,486,233, the entire contents of which are incorporated herein by reference.

[0047] Figure 2B is a flowchart of CMP method 210 according to some embodiments and other embodiments. In step 212, before the source of slurry 17 is modified, it applies mechanical (e.g., acoustic) and / or electromagnetic (e.g., light energy) sources to the unmodified slurry 17.

[0048] In step 215, the slurry source at the wave energy source 133 is further modified by one or more chemical additives 131 supplied to the wave energy source independently of off-the-shelf or other commercially available slurries. In this embodiment, the wave energy source 133 includes: means for applying electromagnetic (e.g., light, wave energy); and a holding means or region for receiving, temporarily holding, and applying the material additive(s) 131 to the slurry in the wave energy device 133. In some embodiments, step 214 is performed before step 215. In other embodiments, steps 214 and 215 are performed in parallel. In other embodiments, step 214 is performed after step 215.

[0049] In step 216, a polishing operation is performed using a slurry modified by both (multiple) material additives 131 and wave energy source 133.

[0050] Figure 2C is a flowchart of CMP method 220 according to some embodiments and other embodiments. Step 222 may be similar to step 202 of Figure 2A, wherein the source of slurry 17 is modified to include one or more material additives 131. In step 223, the modified slurry 17A is output to polishing system 102.

[0051] In step 224, the megaphone processing and / or light enhancement process is directed to the polishing pad 103 of the polishing system 102, and the modified slurry 17A in step 223 is provided on the polishing pad.

[0052] In step 226, a polishing operation is performed on the slurry modified by both the material additives of step 222 and the megasonic treatment and / or light enhancement process of step 224.

[0053] Figure 2D is a flowchart of CMP method 230 according to some embodiments and other embodiments. Unmodified slurry 17 and material additive 131 are independently output (steps 232 and 233, respectively) to polishing equipment 102. In step 234, megaphone processing and / or light enhancement procedures are directed to polishing pad 103, on which slurry 17 from step 232 and material additive 131 from step 233 are independently provided.

[0054] In step 236, a polishing operation is performed on the slurry 17 modified by the material additive 131 of step 233 and the wave energy source 133 that has undergone the megaphone treatment and / or light enhancement process of step 234, all of which are independently directed towards the polishing equipment 102.

[0055] Figure 2E is a flowchart of CMP method 240 according to some embodiments and other embodiments. In step 242, a source of off-the-shelf or commercially available slurry 17 is supplied to polishing equipment 102. In step 243, material additive 131 is supplied to a wave energy source, which applies mechanical and / or electromagnetic wave energy to the material additive 131. In step 244, a megaphone processing and / or light enhancement process supplies modified additive 131 to polishing pad 103, on which the slurry 17 from step 242 is independently supplied.

[0056] In step 246, a polishing operation is performed on the previously unmodified slurry 17 in response to receiving and processing the additive 131 modified by the wave energy source 133 in step 244 to form unmodified slurry 17A at the polishing system 102.

[0057] Figure 3 is a schematic diagram of a CMP slurry processing system 300 according to some embodiments. The slurry processing system 300 may be part of the application system 110 of Figure 1. The slurry processing system 300 is constructed and configured to activate, agitate, blend, filter, circulate, and / or apply slurry sources to the substrate surface. For brevity, some well-known slurry application features are not described in detail. Other features are described in further detail because they include applications, modifications, and variations that fall within the true scope of the inventive concept.

[0058] In some embodiments, the CMP slurry processing system 300 includes a storage container housing 302, an acoustic agitator 304, a piping 306, and a power generator 308. The piping has a non-coiled inlet region 311, a non-coiled outlet region 321, and a coiled section 313 between the non-coiled inlet region 311 and the non-coiled outlet region 321.

[0059] The container housing 302 is constructed and configured as an open-top bowl or similar object to receive and hold a source of deionized water 320 positioned around piping 306. In some embodiments, the top of the container 302 is sealed and includes an inlet for receiving the deionized water 320. The deionized water 320 can fill the container housing 302 to a water level 321, such that a coiled section 313 of piping 306 is immersed in the water, and a non-coiled inlet region 311 extends from and is separate from the container housing 302 holding the deionized water 320. Piping 306 can receive a source of liquid (such as slurry) flowing from an inlet 311 of the non-coiled inlet region 311 to an outlet of the uncoiled outlet region 321 for application to a CMP polishing apparatus. As the slurry travels through the coiled section 313 of the water-immersed piping 306, the power generator 308 activates the sonic agitator 304 to agitate or stimulate the water with sufficient energy in a sonic manner. This agitates the water as the slurry flows through the coiled section 313 of the piping 304 to the non-coiled outlet region 321, and then to a pad on the pressure plate of, for example, the CMP polishing equipment of Figure 1, allowing the sonic waves to extend through the plastic surface of the piping 304 to the slurry. In some embodiments, the sonic agitator 304 includes one or more sonic transducers. In some embodiments, the power generator 308 is an integrated RF power generator.

[0060] Figures 4 through 6A illustrate a slurry processing apparatus 400 according to some embodiments. The slurry processing apparatus 400 may be part of or entirely comprise of the slurry processing system 10 of Figure 1. However, the slurry processing system 10 of Figure 1 is not limited to the slurry processing apparatus 400. For example, the slurry processing system 300 of Figure 3 may be incorporated as part of the slurry processing system 10 of Figure 1. The difference between the slurry processing apparatus 400 and the CMP slurry processing system 300 of Figure 3 is that the slurry processing apparatus 400 of Figures 4 through 6 is encapsulated and leak-proof to allow the apparatus 400 to provide a continuous and direct flow of any type of CMP slurry. Furthermore, the slurry processing apparatus 400 can process slurry in the absence of coiled piping. The slurry processing apparatus 400 is constructed and configured to reduce the inefficiencies that may occur during the acoustic treatment of CMP slurry for polishing operations, wherein the slurry may receive 5% or less of the acoustic energy.

[0061] In some embodiments, the slurry processing equipment 400 includes a container housing 402, a cap sealing system 410, and a set of inlets, outlets, and connectors 411 to 413, 418, and 421.

[0062] The container housing 402 is constructed and configured to be encapsulated and sealed by a capping sealing system 410 (shown in detail in FIG. 6A). The container housing 402 receives and holds a slurry source and is further constructed and configured to allow continuous flow of slurry from an outlet 412. As shown in FIG. 4B, an opening 403 exposes the interior 408 of the housing 402. In some embodiments, the interior 408 is formed of Teflon™ or the like. The interior 408 may include an active area within the interior 408, wherein an acoustic resonator or other acoustic energy generating device 431 is enclosed in a transducer housing 430 (see FIG. 5), which can provide acoustic energy to one of the following sources of slurry (modified slurry 17A modified by chemical additives or unmodified slurry 17 sealed in the container housing 402). In some embodiments, the acoustic energy generating device may be a light energy source, which may be similar to or identical to a light energy source located outside the container housing 402 and directing light towards a slurry source flowing from the outlet pipe 412 or located inside the container housing 402 at 408. In some embodiments, the light energy source is separate from the acoustic energy generating device of the container housing 402. In some embodiments, the acoustic energy generating device may be similar to or identical to a portion of the acoustic energy source 133 of Figures 1-2E or the acoustic agitation device 304 of Figure 3, and therefore details are omitted for simplicity. A power supply (not shown in Figures 4-6, but may be similar to the power supply 304 of Figure 3) may supply power to the acoustic energy generating device. The power supply may be similar to or identical to the RF power generator 308 of Figure 3, and therefore details are omitted for simplicity. In some embodiments, the acoustic energy generating device applies a piezoelectric effect, which generates sound waves and cavitation erosion that agitate the slurry, and then outputs them to a polishing pad on top of the pressure plate of the polishing system 102 (see FIG. 1), wherein the polishing pad polishes the surface of the substrate 20 by removing a chemical passivation layer formed on the surface of the substrate, and then mechanically grinding and being carried away by the slurry.

[0063] As shown in Figures 4, 6, and 6A, the cap sealing system 410 is configured to form a fluid seal over the opening 403 of the container housing 402. The container housing 402 may be configured (e.g., machined) to conform to or mate with clamp portions 401A, 401B, and the cap element 409 to maintain a sealed compression interface between the cap sealing system 410 and the container housing 402. In some embodiments, the cap sealing system 410 includes a sliding fit element 401, a recessed latch O-ring 404, a shear ring 405, and a cap element 409. Details of the cap sealing system 410 are described below.

[0064] In some embodiments, the slurry processing apparatus 400 includes an inlet pipe 411, an outlet pipe 412, a vent pipe 413 (referred to as pipelines respectively), and a gas inlet pipe 418, which are mounted on a circular disc (such as an O-ring 404) and extend through the disc. In some embodiments, the outlet pipe 412 has a length greater than that of the inlet pipe 411 and the vent pipe 413, such that, unlike the inlet pipe 411 and the vent pipe 413, a portion of the outlet pipe 412 extends through at least a portion of the interior of the container housing 402 to be immersed in the slurry within the container housing. The inlet pipe 411 and the vent pipe 413 may extend in a direction away from the container housing 402 into a hole in the O-ring 404. In some embodiments, the three pipes 411-413 are press-fitted and have a height that can be individually adjusted by loosening the nuts 415 (see FIG. 4A) that hold the pipes in place. When nut 415 is loosened, the tubes can move freely up or down from the surface of cover element 409 to a desired height. Then, the nuts can be tightened to secure the tubes against cover element 409, move the tubes up or down to the desired height, and then tightened again to securely hold the tubes in place. Tubes 411-413 and tube 418 can be press-fit and replaceable.

[0065] Inlet pipe 411 provides a slurry inlet to the closed system. Vent pipe 413 provides a vent line to allow trapped air to escape from housing 402 during initial ignition operation, wherein the container receives and is partially or fully filled with slurry before valve 414 at the top of vent pipe 413 is closed, and allows housing 402 to receive a continuous flow of slurry from inlet 411 via cap sealing system 410, which provides a fluid seal at opening 403.

[0066] The gas inlet pipe 418 is configured to inject or impregnate a gas (such as ozone or oxygen) into the container housing 402.

[0067] In some embodiments, the connector 421 at the bottom of the housing 402 shown in FIG4 may include a purge gas reinjection, an RF cable inlet, and a temperature sensor cable, but is not limited thereto.

[0068] Returning to Figures 6 and 6A, in some embodiments, the container housing 402 has a groove 407 formed, either machined or otherwise, around the periphery of the housing 402 and adjacent to the container opening 403, for receiving and fitting a shear ring 405 in place such that the shear ring 405 provides a fluid seal around the container housing 402 when the cap element 409 is removably attached around the container opening 403. This shear ring may be made, for example, by Delrin®.

[0069] The retaining ring element 404 (e.g., an O-ring), also referred to as a retaining O-ring, may be formed of a material (such as rubber, plastic, or the like) that allows the retaining ring element 404 to provide a fluid seal. Specifically, the O-ring 404 seals the top region of the container housing 402, similar to or identical to the inner diameter of the container housing 402's interior 408, limited only by the tolerances of the container housing 402. In some embodiments, the top sealing surface and the groove beneath the cap element 409 (in which the O-ring 404 is positioned) may be machined to achieve a smooth finish. When the O-ring 404 is installed, it maintains a sealed compression interface between the cap sealing system 410 and the container housing 402. In some embodiments, the O-ring 404 is formed of Solid Virgin Teflon™. In some embodiments, the O-ring 404 is formed of a fluoropolymer material such as Viton™ to form an FEP-encapsulated Viton™ O-ring, which provides a high degree of chemical resistance and sufficient compression.

[0070] The cover element 409, also referred to as a cover piece, may be disc-shaped and have a threaded peripheral region 422. The sliding fit element 401, also referred to as a clamp, includes a first clamp portion 401A and a second clamp portion 401B constructed and configured to couple with each other. In this embodiment, the first clamp portion 401A includes two rods 423 extending from the body of the first clamp portion 401A, which are also referred to as threaded rods. In some embodiments, the body has a hemispherical interior 424. The rods 423 can be inserted into holes in the second clamp portion 401B (see FIG. 6A), which also has a hemispherical interior 424. When coupled together, the first clamp portion 401A and the second clamp portion 401B share a central hole formed by the hemispherical interior 424, which is also threaded to engage with the peripheral region 422 of the cover element 409. Furthermore, the rod 423 prevents torque or other rotational forces that could cause the first clamp portion 401A and the second clamp portion 401B to separate from each other, or otherwise affect the seal formed between the cap sealing system 410 and the container housing 402. The central hole 424 includes a threaded collar that surrounds and is threadedly engaged with the threaded peripheral region 422 of the disc 404. In some embodiments, the peripheral region 422 is constructed and configured to taper or, for example, have an angle relative to the threaded interior 424, as shown. For example, the angle may be 45 degrees relative to a vertical axis, such that the width, circumference, diameter, or related dimension of the bottom surface of the disc is greater than that of the top surface. The rod 423, or a fitting or similar, may be threaded to be threadedly engaged with a wing nut 406, which, when rotated, can fasten the first clamp portion 401A and the second clamp portion 401B relative to each other. The wing nut 406 is designed to be tightened by hand regardless of the user's hand size for easy removal and assembly, and allows for gloved handling. The wing nut 406 terminates in a clamp formed by the first clamping portion 401A and the second clamping portion 401B of the sliding-fit element 401, precisely at the correct distance for compression of the O-ring 404 and / or the shear ring 405. The threaded collar, rod 423, and wing nut 406 of the sliding-fit element 401 together form a chord seal around the disc 404 and a chord seal at the cap sealing system 410. The cap sealing system 410 (particularly the O-ring 404) then forms a seal with the shear ring 405 and the groove 407 of the container housing. In some embodiments, the O-ring 404 and the shear ring 405 form a "clamshell" configuration with respect to the opening 403 of the sealed container housing 402. Another feature is that the processing device 400 can be operated by a single person. The first clamp portion 401A and the second clamp portion 401B are interchangeable and can be added or removed from the container shell 402 one at a time, as each can be independently retained or otherwise force applied to the O-ring 404.The wing nut 406 and the rod 423 can be removed interchangeably and one at a time, as each can be independently left in the grooves of the first clamping part 401A and the second clamping part 401B, respectively.

[0071] During the CMP polishing process, liquid slurry is injected into the interior 408 of container 402 through inlet 411 and exits container 402 through outlet 412. Figure 7 shows the polishing results obtained using various methods. Specifically, the removal rates obtained due to copper CMP operations using bulk copper slurry or the like are shown, with no sonic treatment (methods 1 and 4), tube sonic treatment (shown in Figure 3; methods 2 and 5), and continuous flow sonic treatment (shown in Figures 4 to 6; methods 3 and 6). A significant increase in material removal rate is shown under methods 3 and 6 performed by the slurry treatment equipment 400 of Figures 4 to 6. More specifically, the bar chart 700 in Figure 7 shows a higher copper removal rate at a working wafer pressure of 1 PSI as the removal rate increases. At 3 PSI, an additional advantageous copper removal rate is achieved using the slurry treatment equipment 400.

[0072] Figure 8 is a diagram illustrating the operation of a slurry injection system 800 combined with a slurry processing system 400 according to some embodiments. Although the slurry processing apparatus 400 of Figures 4 to 6 is described, the slurry processing system 10 of Figure 1 is equally applicable. For example, the slurry injection system 800 together with the slurry processing apparatus 400 can be part of the slurry processing system 10.

[0073] The slurry injection system 800 is constructed and configured for coupling with a rotary substrate polisher positioned on the wafer 20 (e.g., the wafer polishing apparatus 102 of FIG. 1). During the polishing operation, the slurry injection system 800 is positioned relative to the wafer 20 rotating on the pad 103 of the polishing apparatus such that the source of the modified slurry 17A is output along a path included in the orifice 809 at the bottom portion 808 of the injection apparatus.

[0074] In some embodiments, the slurry is modified by a wave energy source 133 and output from the wave energy source 133 to a slurry injection system 800. Subsequently, the slurry injection system 800 may output the slurry to a polishing pad 103 via a hole 809 and / or a track.

[0075] Figures 9A to 9C illustrate various applications of a wave energy source 133, namely a light wave energy source 112, in a CMP slurry processing system according to some embodiments. The light wave energy source 112 may include a pump or the like that can output slurry source to one or more light-emitting elements, after which the slurry modified by the light energy emitted by the light-emitting elements can be output from the light wave energy source 112.

[0076] The method 900 shown in Figure 9A may begin at step 902, wherein one source of slurry 17 is modified to form a modified slurry 17A, the modified slurry comprising one or more material additives 131, such as chemical additives. In other embodiments, the slurry is unmodified, for example, off-the-shelf or other commercially available slurry 17. Material additives 131 may be selected based on their functionality, such as those described in the examples below. In other embodiments, other slurry additives may modify the surface tension of the liquid and the contact angle with the substrate, such as those described in the examples below.

[0077] In step 904, a light energy source 112 applies electromagnetic energy (e.g., light) to the modified slurry 17A. In some embodiments, the light energy source 112 is integrated into the slurry processing system (e.g., a portion of the light energy source 133 of the slurry processing system 10 of FIG. 1) or is integral with the container housing 402 of the slurry processing apparatus 400 of FIGS. 4-6. In other embodiments, the light energy source 112 is separate from the slurry processing system, for example, close to the wafer 20 on the polishing pad 103 shown in FIG. 1. In some embodiments, the light energy source acts on a photosensitivity-enhancing material additive within the slurry. In some embodiments, in addition to or instead of the material additive of step 902, an additive comprising a photosensitizing compound medium is added. In some embodiments, the light energy source may be operated in conjunction with, for example, the slurry injection system shown in FIG8, and / or the slurry injection system described in one or more of the following patents: U.S. Patent No. 8,197,306, U.S. Patent No. 8,845,395, U.S. Patent No. 9,296,088, Korean Patent No. 1,394,745, Japanese Patent No. 5,574,597, and Taiwan Patent No. 1,486,233, the entire contents of which are incorporated herein by reference.

[0078] In step 906, a polishing operation is performed on the slurry modified by (multiple) material additives 131 and light wave energy source 112.

[0079] The method 910 shown in Figure 9B includes steps 912 and 914, which are similar to steps 902 and 904 in Figure 9A, and are therefore not repeated for the sake of brevity.

[0080] In step 916, the slurry modified by the material additive(s) 131 and the light energy source 112 is output to the acoustic energy source 113. In some embodiments, the slurry may flow through a mega-sonic processing procedure performed by the light energy source 133. In some embodiments, the acoustic energy source 113 is integrated into the slurry processing system (e.g., a portion of the light energy source 133 of the slurry processing system 10 of FIG. 1) or is integral with the container housing 402 of the slurry processing apparatus 400 of FIG. 4 through 6. In other embodiments, the acoustic energy source 113 is separate from the slurry processing system, for example, close to the wafer 20 on the polishing pad 103 shown in FIG. 1.

[0081] In step 918, a polishing operation is performed on the slurry modified by each of the material additive 131, the light wave energy source 112, and the sound wave energy source 113.

[0082] The method 920 shown in Figure 9C includes steps 922 and 924 similar to steps 902 and 904 in Figure 9A and steps 912 and 914 in Figure 9B, and therefore will not be repeated for the sake of brevity. Method step 920 is similar to method 910 in Figure 9B, except that in step 926, the slurry modified by each of the (multiple) material additives 131 is first output to the sound energy source 113, and then in step 928, it is output to the polishing system 102.

[0083] The following is a set of examples illustrating the operations performed by the slurry processing technology of the CMP slurry processing system described in one or more embodiments herein.

[0084] In one example, the wafer polishing apparatus (e.g., shown in Figure 1) has a concentric trench pad located on at least one 300-mm blanket tungsten wafer. The polishing time is configured to 45 seconds. The slurry comprises Versum DP1142-1 containing 2% H₂O₂. Another example slurry formulation may include, but is not limited to, 1.0 wt% glycine, 0.5 wt% 60 nm SiO₂, 100 ppm BTA, 1.0 wt% H₂O₂, and has a pH of 5.8. Another example slurry formulation may include, but is not limited to, 1.0 mM hydroquinone and 1.0 wt% calcined cerium oxide, and has a pH of 4.0. Another example slurry may include an inhouse formulation comprising 1.0 mM glutamic acid and 1.0 wt% calcined cerium oxide, and has a pH of 4.0.

[0085] In another example, the slurry injection system 800 shown in Figure 8 is configured to process slurry at a flow rate of 125 ml / min. The pad 103 rotates at 70 RPM, with a sinusoidal sweep schedule of 10 sweeps per second. A downward force of 7 lbs is applied to the pad. A 45-minute break-in period occurs at a pad rotation rate of 80 RPM. A non-in-situ finishing procedure occurs for 30 seconds. The conventional and present invention application system is configured to apply a polishing pressure of 4 PSI. The sliding speed is 1.6 m / s. The power intensity provided by both the conventional slurry application system and the slurry processing equipment 400 is configured to 20 W.

[0086] As described above, the CMP paste processing system 10 may include a portion of the light energy source relating to a substrate 20 formed of copper, tungsten, silicon carbide, silicon dioxide, or combinations thereof or alloys thereof, and / or other substrate materials used for polishing operations in shallow trench isolation (STI) CMP applications requiring the use of paste. In some embodiments, the CMP application includes a plasma-enhanced tetraethyl orthosilicate (PE-TEOS) SiO₂ CMP process. In some embodiments, the photosensitive paste for STI CMP may be provided by utilizing a ligand-metal charge transfer (LMCT) mechanism between a complex additive and CeO₂ nanoparticles, which in turn can enhance the removal rate during the CMP process. Additives including ligands allow electrons to transfer from the ligands to the metal surface of the substrate, thus resulting in the reduction of metal ions by the ligands.

[0087] In another example, ligand misaligners (such as tyrosine (Tyr), phenylalanine (Phe), tryptophan (Trp), histidine (HID), and glycine (Gly)) bond with human metal ions or similar substances on the surface of the metal oxide substrate, resulting in the formation of a metal oxide-ligand misalignment. Upon irradiation of this misalignment, for example by the light-generating system 912 shown in Figures 9A to 9C, electrons from the coordinating carboxylic acid ester groups are excited and subsequently transferred to the conduction band (CB) of CeO₂. This then reduces Ce⁴⁺ to Ce³⁺ and desorbs surface O₂. Therefore, the availability of oxygen vacancies for nucleophilic attack is increased. Furthermore, throughout the process, the ligands are oxidized to prevent re-adsorption to nanoparticles, which enhances the usable surface area. Therefore, during the polishing operation, the oxide removal rate is enhanced as surface activity (i.e., the availability of oxygen vacancies) increases.

[0088] In another example, slurry processing techniques may include polymer-based nanocomposite slurries formed by incorporating macromolecular polymers (such as, but not limited to, algae and pectin) with additives that form a complex. Such material additives provide bifunctionality within the polymer, i.e., for (1) crosslinking the polymer matrix; and (2) self-integration within a self-cleaning / stress-responsive core. Complex additives may include co-rate-accelerating additives, such as, but not limited to, glycine (Gly), L-serine (Ser), itac, oxalic acid (Ox), succinic acid (Succ), and hydroquinone (HQ). Furthermore, photosensitive derivatives of the molecules (such as azobenzenes, cyclodextrin, Schiff base ligands, spiropyran, and polyamines) may be integrated (covalently or non-covalently) onto the outer surface of the polymer complex to provide controlled release of rate-enhancing additives after irradiation and to enhance contaminant removal (i.e., metal ions and / or organometallic complex residues). The photosensitive functionality derived from molecular-level covalent bonds can undergo switchable isomerization after irradiation with illumination in the ultraviolet, visible, or infrared ranges by the light-generating system or related energy source described in the embodiments herein. Furthermore, after irradiation with light of a specific wavelength, the material additives exhibit rate-enhancing properties to control the substrate removal rate in situ.

[0089] According to some embodiments, the removal rate of SiC substrates can be enhanced by employing megahertz energy. In this case, sound waves and light waves are applied alone or in combination via a polishing apparatus (e.g., shown in FIG. 1) to enhance process performance.

[0090] More specifically, in the pre-acoustic processing state, reactive chemistry resulting from one or more of the techniques described in the embodiments herein can drive the film formation kinetics at the SiC substrate, leading to the formation of a wear-resistant layer. While this layer can be soft, it can also be dense. Therefore, a significant amount of mechanical energy (i.e., high values ​​of pressure and sliding speed) is required to remove the soft passivation layer and the surface topology via polishing. Upon exposure to acoustic processing, a shift in the dynamic equilibrium at the substrate surface occurs due to the release of additives and the generation of increased critical reactive oxygen species (ROS). These additives reduce the density of the surface passivation film, resulting in even "softer" and less mechanically dependent interactions. This, in turn, produces a higher removal rate with lower operating pressures and sliding speeds. These paired systems (i.e., the combination of slurry formulation and mega-acoustic processing) result in synergistic improvements that significantly increase material removal rates while reducing process time, improving defect severity (due to the need for less mechanical action), and maximizing consumable life.

[0091] The following are a series of exemplary experiments demonstrating the application of one or more of the aforementioned wafer polishing techniques to polishing slurries, comparing the results with the application of acoustic and / or optical waves to the polishing slurry without acoustic treatment or other wave application. Here, an internally formulated bulk copper slurry containing colloidal silicon dioxide nanoparticles (NP), water, hydrogen peroxide, a copper chelating agent (such as glycine), and a copper passivating agent (such as benzotriazole) was used in the experiments. For example, a concentric trench pad (e.g., a DuPont IC1000® pad) was positioned on a 200-mm rotating platen. A 3M (S60-AI) diamond dressing disc in non-in-situ dressing mode was used for a duration of 1 minute. A copper substrate with a diameter of 25 mm and a thickness of 18 mm was polished. The process pressure ranged between 1 and 5 PSI. The slide speed ranged between 0.25 and 1.05 m / s. The slurry flow rate ranged between 25 and 100 cc / min. The applied acoustic energy ranged from 0 to 2.0 watts per square centimeter. After polishing a total of 90 copper substrates, and depending on the process conditions, when the acoustic treatment energy was set to zero (0) watts per square centimeter (i.e., no acoustic treatment), the observed copper removal rate ranged from 1,061 to 4,270 angstroms per minute. At 1.5 watts per square centimeter, based on polishing another 90 wafers, the copper removal rate ranged from 1,207 to 6,219 angstroms per minute. For comparison, under processing conditions of 5 PSI pressure, 0.65 m / s sliding speed, and 100 cc / min flow rate, the test without acoustic treatment yielded an average copper removal rate of 3,558 angstroms per minute. Conversely, the test at an acoustic treatment energy of 1.5 watts per square centimeter resulted in an average removal rate of 6,219 angstroms per minute. This corresponds to a 43% increase in copper removal rate with acoustic treatment. In the case of ultrasonic slurry treatment, the slurry incubation time in the continuous flow ultrasonic generator is zero. That is, the slurry is not held stagnant (or exhibits any kind of fixed pattern) for any period of time in the reactor. Instead, it is continuously ultrasonically treated as it flows through and toward the polisher.

[0092] In another example, Fujimi Corporation PL-7106® commercial copper paste (according to manufacturer's specifications) mixed with water and hydrogen peroxide was used. A DuPont IC1000® concentric groove pad was employed on a 200-mm rotary press. Additionally, a 3M (S60-AI) diamond dressing disc was used in non-in-situ dressing mode for a duration of 1 minute. Copper substrates with a diameter of 25 mm and a thickness of 18 mm were polished. The applied process pressure ranged between 1 and 5 PSI. The slide speed ranged between 0.25 and 1.05 m / s. The paste flow rate ranged between 25 and 100 cc / min. After polishing 90 copper substrates, and depending on the process conditions, the copper removal rate observed without any sonic treatment ranged from 1,127 to 6,325 angstroms / min. After polishing another 90 wafers at 1.5 W / cm², the copper removal rate ranged from 1,578 to 6,723 Å / min. For comparison, under processing conditions of 5 PSI pressure, 1.05 m / s flow rate, and 62.5 cc / min, the results without any sonic treatment yielded an average copper removal rate of 6,325 Å / min, while at 1.5 W / cm² sonic treatment energy, an average copper removal rate of 6,723 Å / min was observed. This corresponds to a 6% increase in copper removal rate with sonic treatment. In the case of slurry sonic treatment, the slurry incubation time in the continuous flow ultrasonic generator was zero. That is, the slurry was not held stagnant (or exhibiting any kind of hold-up pattern) for any period of time in the reactor. Instead, it was continuously sonicated while flowing through and towards the polisher. Further supporting evidence was seen under processing conditions of 1 PSI and an electrode rotation speed equivalent to 0.25 m / s. In this case, clear evidence of corrosion displacement was observed when measuring 1.45 microamperes without acoustic treatment. This was further supported by acoustic treatment at 1.5 watts per square centimeter, which increased the current to 18.6 microamperes.

[0093] In another example, Cabot Microelectronics Corporation SSW7300® commercial tungsten paste (according to manufacturer specifications) mixed with water and hydrogen peroxide was used. Additionally, DuPont IC1000® concentric groove pads were employed on a 200-mm rotary press. Furthermore, a 3M (S60-AI) diamond dressing disc was used in non-in-situ dressing mode for a duration of 1 minute. Tungsten substrates with a diameter of 25 mm and a thickness of 18 mm were polished. The applied process pressure ranged between 1 and 5 PSI. The sliding speed ranged between 0.25 and 1.05 m / s. The paste flow rate ranged between 25 and 100 cc / min. The acoustic energy ranged between zero and 1.5 watts / cm². After polishing 90 tungsten substrates, and depending on the process conditions, the observed tungsten oxide removal rate ranged from 1,812 to 2,170 angstroms / min without acoustic treatment. At 1.5 W / cm², after polishing another 90 wafers, the tungsten removal rate ranged from 2,204 to 2,712 Å / min. For comparison, under processing conditions of 5 PSI pressure, 1.05 m / s slide velocity, and 62.5 cc / min flow rate, the average tungsten removal rate tested without ultrasonic treatment was 2,129 Å / min. At 1.5 W / cm², an average removal rate of 2,712 Å / min was observed, corresponding to an increase of 27%. In the case of slurry ultrasonic treatment, the slurry incubation time in the continuous flow ultrasonic generator was zero. That is, the slurry was not held stagnant (or exhibiting any kind of fixed pattern) for any period of time in the reactor. Instead, continuous ultrasonic treatment was performed as the slurry flowed through and towards the polisher.

[0094] In another example, Versum Materials CopperReady 3930® commercial bulk copper paste (according to manufacturer specifications) mixed with water and hydrogen peroxide was used. Additionally, Dupont IC1000® concentric groove pads were employed on a 200-mm rotary press. A 3M (S60-AI) diamond dressing disc in non-in-situ dressing mode was also used for a duration of 1 minute. Copper substrates with a diameter of 25 mm and a thickness of 18 mm were polished. Process pressure ranged between 1 and 5 PSI. Slide speed ranged between 0.25 and 1.05 m / s. Paste flow rate ranged between 25 and 100 cc / min. Acoustic setpoint was zero and 1.5 watts / cm². After polishing 90 copper substrates, and depending on process conditions, the observed copper removal rate ranged from 2,307 to 9,043 angstroms / min when the acoustic processing energy was turned off. After polishing another 90 wafers at 1.5 W / cm², the copper removal rate ranged from 2,519 to 13,512 Å / min. For comparison, under processing conditions of 5 PSI pressure, 0.65 m / s slide velocity, and 100 cc / min flow rate, an average copper removal rate of 9,043 Å / min was observed without any ultrasonic treatment, while at the ultrasonic treatment energy of 1.5 W / cm², an average copper removal rate of 13,512 Å / min was observed. This corresponds to an increase of 49%. In the case of slurry ultrasonic treatment, the slurry incubation time in the continuous flow ultrasonic generator is zero. That is, the slurry is not held stagnant (or exhibits any kind of fixed pattern) for any period of time in the reactor. Instead, it is continuously ultrasonically treated while flowing through and towards the polisher.

[0095] In another example, Versum Materials CopperReady 3930® commercial bulk copper paste (according to manufacturer specifications) mixed with water and hydrogen peroxide was used. A Dupont IC1000® concentric groove pad on a 200-mm rotary press and a 3M (S60-AI) diamond dressing disc in non-in-situ dressing mode were also employed for a duration of 1 minute. Copper substrates with a diameter of 25 mm and a thickness of 18 mm were polished. Process pressure ranged between 1 and 5 PSI. Slide speed values ​​ranged between 0.25 and 1.05 m / s. Paste flow rate ranged between 25 and 100 cc / min. Acoustic energy setpoints were 0.5, 1.5, or 2.0 W / cm². After polishing 20 copper substrates, and depending on process conditions, when the acoustic processing energy was set to 0.5 W / cm², the observed copper removal rate ranged from 5,563 to 11,504 Å / min. After polishing an additional 20 copper substrates, and depending on process conditions, the observed copper removal rate ranged from 5,789 to 11,377 Å / min when the ultrasonic treatment energy was set to 1.5 W / cm². After polishing another 20 copper substrates, and depending on process conditions, the observed copper removal rate ranged from 2,238 to 7,118 Å / min when the ultrasonic treatment energy was set to 2.0 W / cm². The results indicate that the average copper removal rate decreased by 40% as the ultrasonic treatment energy increased from 0.5 to 2.0 W / cm². However, as the ultrasonic treatment energy was further increased to 30 W, the average copper removal rate decreased by 10% from its high of 23 W. In the case of slurry ultrasonic treatment, the slurry incubation time in the continuous flow ultrasonic generator was zero. That is, the slurry did not remain stagnant (or exhibit any kind of holding pattern) for any period of time in the reactor. Instead, sonic processing is performed continuously as the material flows through and toward the polisher. This indicates that, at least when polishing small substrates, higher sonic processing energy is not necessarily better.

[0096] In another example, Versum Materials CopperReady 3935® commercial high-rate copper paste (according to manufacturer specifications) mixed with water and hydrogen peroxide, along with Dupont IC1000® concentric groove pads on a 200-mm rotary press, and a 3M (S60-AI) diamond dressing disc in non-in-situ dressing mode, were used for a duration of 1 minute. Copper substrates with a diameter of 25 mm and a thickness of 18 mm were polished. Process pressure ranged between 1 and 5 PSI. Slide speed ranged between 0.25 and 1.05 m / s. Paste flow rate ranged between 25 and 100 cc / min. Acoustic setpoints were 0, 0.5, and 1.5 watts / cm². After polishing 14 copper substrates, and depending on process conditions, the observed copper removal rate without acoustic treatment ranged from 2,069 to 9,512 angstroms / min. After polishing another 14 copper substrates, and depending on the process conditions, the observed copper removal rate ranged from 2,360 to 9,741 Å / min when the acoustic treatment energy was set to 0.5 W / cm². After polishing another 14 copper substrates, and depending on the process conditions, the observed copper removal rate ranged from 2,586 to 8,858 Å / min when the acoustic treatment energy was set to 1.5 W / cm². The results indicate that the average copper removal rate increased by 10% as the acoustic treatment energy increased from zero to 0.5 W / cm². However, as the acoustic treatment energy was further increased from 0.5 to 1.5 W / cm², the average copper removal rate decreased by 5% from its high value at 0.5 W / cm². Dynamic electrochemical analysis performed under the same pressure, slurry flow rate, and velocity as the polishing conditions described above indicated that the corrosion current ranged from 1.29 to 4.34 μA when the acoustic treatment energy was set to zero. At an ultrasonic treatment energy of 0.5 W / cm², the corrosion current increases, ranging from 1.34 to 5.20 μA. However, at an ultrasonic treatment energy of 1.5 W / cm², the corrosion current decreases from its high value, ranging from 0.56 to 3.22 μA. The trend of the corrosion current results is consistent with the trend of the removal rate. In the case of slurry ultrasonic treatment, the slurry incubation time in the continuous flow ultrasonic generator is zero. That is, the slurry is not held stagnant (or exhibits any kind of fixation pattern) in the reactor for any period of time. Instead, it is continuously ultrasonically treated while flowing through and toward the polisher.

[0097] In another example, Versum Materials Barrier 6250® commercial barrier paste (according to manufacturer's specifications) mixed with water and hydrogen peroxide was used. A Fujibo H800® embossing pad on a 200-mm rotary press and a 3M (PB33A-1) stiff-bristled brush dressing disc in non-in-situ dressing mode were also used for a duration of 1 minute. Tantalum substrates with a diameter of 25 mm and a thickness of 18 mm were polished. Process pressure ranged between 1 and 5 PSI. Slide speed ranged between 0.25 and 1.05 m / s. The paste flow rate was kept constant at 62.5 cc / min. Acoustic setpoints were 0, 0.5, or 1.5 watts / cm². After polishing 14 tantalum substrates, and depending on process conditions, the tantalum removal rate observed without acoustic treatment ranged from 250 to 830 angstroms / min. After polishing another 14 tantalum substrates, and depending on the process conditions, the observed tantalum removal rate ranged from 380 to 810 Å / min when the acoustic processing energy was set to 0.5 W / cm². After polishing another 4 tantalum substrates, and depending on the process conditions, the observed tantalum removal rate ranged from 496 to 1,045 Å / min when the acoustic processing energy was set to 1.5 W / cm². The results indicate that the average tantalum removal rate increases by 20% as the acoustic processing energy increases from zero to 0.5 W / cm². As the acoustic processing energy is further increased to 1.5 W / cm², the average tantalum removal rate increases by an additional 10% from its value at 0.5 W / cm².

[0098] In another example, Versum Materials Barrier 6250® commercial barrier paste (according to manufacturer's specifications) mixed with water and hydrogen peroxide was used. A Fujibo H800® embossing pad on a 200-mm rotary press and a 3M (PB33A-1) stiff-bristled brush dressing disc in non-in-situ dressing mode were also used for a duration of 1 minute. Copper substrates with a diameter of 25 mm and a thickness of 18 mm were polished. Process pressure ranged between 1 and 5 PSI. Slide speed ranged from 0.25 to 1.05 m / s. The paste flow rate was kept constant at 62.5 cc / min. Acoustic energy was set to 0, 0.5, or 1.5 watts / cm². After polishing 14 copper substrates, and depending on process conditions, the observed copper removal rate ranged from 371 to 635 angstroms / min without acoustic treatment. After polishing another 14 copper substrates, and depending on the process conditions, the observed copper removal rate ranged from 497 to 1,016 Å / min when the acoustic processing energy was set to 0.5 W / cm². After polishing another 14 copper substrates, and depending on the process conditions, the observed copper removal rate ranged from 583 to 1,219 Å / min when the acoustic processing energy was set to 1.5 W / cm². The results indicate that the average copper removal rate increases by 40% as the acoustic processing energy increases from zero to 0.5 W / cm². As the acoustic processing energy is further increased to 1.5 W / cm², the average copper removal rate increases by an additional 15% from its initial average at 0.5 W / cm². At zero W / cm², the average copper-to-tantalum removal rate selectivity is 1.04:1. At 1.5 W / cm², the average copper-to-tantalum removal rate selectivity is 1.18:1. In the case of ultrasonic slurry treatment, the slurry incubation time in the continuous flow ultrasonic generator is zero. That is, the slurry is not held stagnant (or exhibits any kind of fixed pattern) for any period of time in the reactor. Instead, it is continuously ultrasonically treated as it flows through and toward the polisher.

[0099] The following examples include the processes described above, including light- or sound-activated chemical additives.

[0100] In one instance, ultrasonically activated chemicals can be added to off-the-shelf slurries, particularly for the preparation of internally formulated slurries containing calcined cerium nanoparticles and redox additives for shallow trench isolation (STI) CMP applications. The material additives are selected based on their functionality. Glutamic acid, with its carboxylic acid functionality, is known to inhibit oxide removal, while hydroquinone is known to enhance oxide removal using its hydroxyl functionality. A 1-minute duration was achieved using a DuPont IC1000® concentric trench pad on a 200-mm rotary platen and a 3M (S60-AI) diamond dressing disc in non-in-situ dressing mode. Polishing was performed using a 1-inch diameter silicon wafer deposited with a tetraethyl orthosilicate (TEOS)-based silicon dioxide film. Process pressures ranged between 0.5 and 1.5 PSI. The slide speed was kept constant at 0.52 m / s. The slurry flow rate was kept constant at 75 cc / min. For the case without acoustic processing, the TEOS wafer removal rate observed using 1.0 millimole hydroquinone ranged from 3,652 to 6,008 Å / min. For acoustic processing at 1.5 W / cm², the TEOS wafer removal rate observed using 1.0 millimole hydroquinone ranged from 3,124 to 7,587 Å / min. This corresponds to a 10% reduction in low-frequency acoustic processing, but an average increase of 12% with increasing acoustic processing power. For the case without acoustic processing, the TEOS wafer removal rate observed using 1.0 millimole glutamate ranged from 3,558 to 5,876 Å / min. For acoustic processing at 1.5 W / cm², the TEOS wafer removal rate observed using 1.0 millimole glutamate ranged from 3,611 to 7,831 Å / min. This corresponds to an average increase of 10%. In the case of ultrasonic slurry treatment, the slurry incubation time in the continuous flow ultrasonic generator is zero. That is, the slurry is not held stagnant (or exhibits any kind of fixed pattern) for any period of time in the reactor. Instead, it is continuously ultrasonically treated as it flows through and toward the polisher.

[0101] In another example, an internally formulated slurry for shallow trench isolation (STI) CMP applications was prepared by utilizing a ligand-metal charge transfer (LMCT) mechanism between misaligned additives and cerium oxide (colloidal or calcined) nanoparticles (NPs). More specifically, ligands (such as tyrosine (Tyr), phenylalanine (Phe), tryptophan (Trp), histidine (His), and glycine (Gly)) often misalign with the metal oxide surface via coordinate bonds, resulting in a misalignment reaction between the metal oxide (MOX) and the ligand. Upon irradiation of this misalignment (with light wavelengths in the range of 250 to 800 nm), electrons from the coordinating carboxylic acid ester groups are excited and ultimately transferred to the conduction band (CB) of the cerium oxide NP. This subsequently reduces Ce⁴⁺ to Ce³⁺ and induces surface O₂ desorption, thereby increasing the availability of oxygen vacancies for nucleophilic attack. Additionally, throughout this process, the ligands are oxidized to prevent re-adsorption to the nanoparticles, which enhances the available surface area. Therefore, the oxide removal rate is significantly enhanced as surface activity (i.e., available oxygen vacancies) increases. This experimental setup allows the slurry to be pumped through clear acrylic piping. The slurry can then be irradiated by laser light or by light transmitted through an array of LEDs. For example, the clear piping section is an acrylic pipe with an inner diameter (ID) of approximately 2 inches and a length of 18 inches. This piping is covered by a 16.4-foot LED strip composed of 300 individual LEDs. The wavelengths of these strips are in the range of 250 nm to 800 nm. An internally formulated STI slurry is prepared using calcined cerium oxide (NP) dispersed in water. Tyrosine is then added to the slurry for efficient charge transfer. A DuPont IC1000® concentric groove pad is used on a 200-mm rotating platen. A 3M (model number) diamond dressing disc in an in-situ dressing mode was also used for a duration of 1 minute. Polishing was performed using 1-inch diameter silicon wafers deposited with silicon dioxide (using tetraethyl orthosilicate as a precursor). Process pressure ranged between 1 and 5 PSI. Slide speed ranged between 0.25 and 1.05 m / s. Slurry flow rate remained constant at 75 cc / min. After polishing the silicon dioxide wafers, the film removal rate observed without irradiation ranged from 2,753 to 3,109 Å / min. After polishing another 20 silicon dioxide wafers, the film removal rate observed under irradiation with 520 to 525 nm green LEDs ranged from 2,948 to 3,650 Å / min. This corresponds to an average increase of 10%.

[0102] In another example, Versum Materials CopperReady 3930® commercial bulk copper paste (according to manufacturer specifications) mixed with water and hydrogen peroxide was used. A Dupont IC1000® concentric groove pad on a 200-mm rotary platen and a 3M (S60-AI) diamond dressing disc in non-in-situ dressing mode were also employed for a duration of 1 minute. The copper substrates used for polishing had a diameter of 25 mm and a thickness of 18 mm. The process pressure was 3 PSI, the slide speed was 0.79 m / s, and the paste flow rate was kept constant at 65 cc / min. Acoustic energy was set at 0 or 1.5 watts / cm². After polishing 10 copper substrates, the average copper removal rate observed without any acoustic treatment was 2,609 angstroms / min. After polishing six more copper substrates, without any incubation time, the average copper removal rate observed was 3,623 Å / min when the paste was sonicated at 1.5 W / cm². After polishing seven more copper substrates, without any incubation time, the average copper removal rate observed was 4,258 Å / min when the paste was sonicated at 1.5 W / cm² (but this time after a 1-minute incubation). This corresponds to a 39% increase between the no-sonic-treatment case and the case with a 1-minute incubation.

[0103] In another example where ultrasonically activated chemicals can be added to off-the-shelf slurries, an internally formulated silicon carbide CMP slurry (containing alumina (spherical or elongated elliptical) NP, water, and hydrogen peroxide) and electrophilic enhancers (such as organometallic complexes (i.e., Cu + 2-glycine)) or borate derivatives were used. A DuPont SUBA800-II-12® XY trench pad on a 200-mm rotating platen and a 3M (PB33A-1) stiff-bristled brush dressing disc in non-in-situ dressing mode were also used for a duration of up to 1 minute. Silicon carbide wafers with a diameter of 100 mm and a total thickness of 500 micrometers were used for all polishing tests. Process pressures ranged between 1 and 9 PSI. Slide speeds ranged between 0.25 and 1.05 m / s, while slurry flow rates ranged between 25 and 100 cc / min. Acoustic setpoints were used between 0 and 2.0 watts per square centimeter. The silicon surface of a silicon carbide substrate was polished using a hydrogen peroxide-based formulation containing an electrophilic enhancer. Depending on the process conditions, when the ultrasonic treatment energy was set to zero watts per square centimeter, the observed removal rates ranged from 1,223 to 1,792 nm / hour. At 1.5 watts per square centimeter, the silicon carbide removal rate ranged from 2,764 to 4,122 nm / hour. These represent an average increase of 58%. In the case of slurry ultrasonic treatment, the slurry incubation time in the continuous flow ultrasonic generator was five minutes. That is, the slurry was not kept stagnant (or exhibiting any kind of fixed pattern) in the reactor for any period of time. Instead, it was continuously ultrasonically treated while flowing through and toward the polisher. The foregoing included the addition of ultrasonic activating chemicals to the ready-made slurry.

[0104] In another example, Versum Materials CopperReady 3930® commercial bulk copper paste (according to manufacturer's specifications), mixed with water and hydrogen peroxide, was used for polishing. A Dupont IC1000® concentric groove pad was used on a 200-mm rotary press. A 3M (S60-AI) diamond dressing disc in non-in-situ dressing mode was used for a duration of 1 minute. Copper substrates with a diameter of 25 mm and a thickness of 18 mm were used for polishing. Process pressure ranged between 1 and 5 PSI. Slide speed ranged between 0.25 and 1.05 m / s. Paste flow rate ranged from 65 to 120 cc / min. At a 1-minute incubation time, the energy remained constant at 1.5 W / cm². After polishing 10 copper substrates, at a paste flow rate of 65 cc / min, the observed copper removal rate ranged from 3,433 to 5,132 Å / min. After polishing 10 copper substrates at a slurry flow rate of 120 cc / min, the observed copper removal rates ranged from 3,713 to 6,020 Å / min. In all cases, higher pressure resulted in higher removal rates. Furthermore, higher flow rates caused an average increase of 10% in the removal rate.

[0105] In another example, Versum Materials CopperReady 3930® commercial bulk copper paste (according to manufacturer specifications) mixed with water and hydrogen peroxide was used. Dupont IC1000® concentric groove pads on a 200-mm rotary press were also used. A 3M (S60-AI) diamond dressing disc in an in-situ dressing mode was further used for a duration of 1 minute. Copper substrates with a diameter of 25 mm and a thickness of 18 mm were polished. Process pressure ranged between 1 and 5 PSI. Glide speed ranged between 0.25 and 1.05 m / s. The paste flow rate was kept constant at 65 cc / min. The sonic treatment energy settings were 0, 0.5, 1, 1.5, and 2 W / cm². In all cases, a 1-minute incubation time was used. After polishing 10 copper substrates, the average copper removal rate observed without sonic treatment was approximately 2,572 Å / min. At 0.5 W / cm², the removal rate increased to a maximum average of 4,959 Å / min, and then steadily decreased to 4,455, 3,845, and 3,500 Å / min as the ultrasonic processing energy increased to 1, 1.5, and 2 W / cm², respectively. This indicates that excessive oxidation (i.e., an increase in reactive oxygen species) may alter the passivation misalignment characteristics at the copper surface, which may be detrimental to the removal rate.

[0106] In another example, Versum Materials CopperReady3930® commercial bulk copper paste (according to manufacturer specifications) mixed with water and hydrogen peroxide was used. A Dupont IC1000® concentric trench pad was employed on a 200-mm rotary press. A 3M (S60-AI) diamond dressing disc in non-in-situ dressing mode was used for a duration of 1 minute. The copper substrate used for polishing had a diameter of 25 mm. The process pressure was 3 PSI, the slide speed was 0.52 m / s, and the paste flow rate was kept constant at 65 cc / min. After polishing, the copper surface was analyzed using atomic force microscopy. Without acoustic treatment, the average wafer surface roughness (Ra) was 1.1 nm. When the acoustic energy was set to 2.0 W / cm², the average wafer surface roughness (Ra) decreased to 0.78 nm. This represents a 29% improvement in surface roughness.

[0107] In another example, Versum Materials DP1236® commercial tungsten paste (according to manufacturer's specifications) mixed with hydrogen peroxide was used. A DuPont IC1000® concentric trench pad was employed on a 200-mm rotating platen. A 3M (S60-AI) diamond dressing disc was operated for up to 1 minute in non-in-situ dressing mode. The tungsten substrate was polished at a polishing pressure of 3 PSI, a sliding speed of 0.52 m / s, and a paste flow rate of 65 cc / min. After polishing, the surface of the tungsten substrate was analyzed using atomic force microscopy. Without acoustic treatment, the average wafer surface roughness (Ra) was 1.07 nm. When the acoustic energy was set to 2.0 W / cm², the average wafer surface roughness (Ra) decreased to 0.88 nm. This represents an 18% improvement in surface roughness.

[0108] The following examples include large (200-mm) wafer polishing with and without the acoustic processing described in the embodiments above.

[0109] In one instance, Versum Materials CopperReady 3930® commercial copper paste (according to manufacturer specifications) mixed with water and hydrogen peroxide was used. Additionally, DuPont IC1010® concentric trench pads were employed on an 800-mm rotary press. A Saesol 4DNS80AMC1 diamond dressing disc was used in in-situ dressing mode. For each wafer, a 200-mm control copper wafer was polished for 30 seconds. The process pressure ranged between 1.5 and 2.0 PSI. The slide speed was set at 1.5 m / s. The paste flow rate was kept constant at 150 cc / min. At a 15-minute incubation time, the acoustic setpoint was 1 watt / cm². Two polishing passes were performed for each combination of polishing conditions. At a polishing pressure of 1.5 PSI, the average copper removal rates were 8,599 and 9,629 Å / min in the process without acoustic treatment and with acoustic treatment, respectively. This represents a 12% increase in removal rate. At a polishing pressure of 2.0 PSI, the average copper removal rates in the processes with and without acoustic treatment were 10,975 and 12,223 Å / min, respectively. This represents an 11% increase in removal rate.

[0110] In another example, Versum Materials CopperReady 3930® commercial copper paste (according to manufacturer specifications) mixed with water and hydrogen peroxide was used. Dupont IC1010® concentric trench pads were employed on an 800-mm rotary platen, along with a Saesol 4DNS80AMC1 diamond dressing disc in in-situ dressing mode. For each wafer, a 200-mm control copper wafer was polished for 30 seconds. The process pressure ranged between 1.5 and 2.0 PSI. The slide speed was kept constant at 1.5 m / s. Furthermore, the paste flow rate was kept constant at 150 cc / min. Without sonic treatment, the average copper removal rates at polishing pressures of 1.5 and 2.0 PSI were 9,372 and 11,919 Å / min, respectively. When the acoustic energy setpoint is set at 0.5 watts / cm² with a 15-minute incubation time, the copper removal rate increases to 12,260 angstroms / minute at a polishing pressure of 2.0 PSI, representing a 3% increase in removal rate. At an acoustic energy setpoint of 1.0 watts / cm², and again with a 15-minute incubation time, the average copper removal rates at polishing pressures of 1.5 and 2.0 PSI are 9,660 and 13,314 angstroms / minute, respectively. This represents increases in removal rate of 3% and 12% compared to the process without acoustic treatment. When the acoustic energy setpoint is 1.5 watts / cm² with a 5-minute incubation time, the copper removal rates at polishing pressures of 1.5 and 2.0 PSI are 9,704 and 13,026 angstroms / minute, respectively. This represents increases in removal rate of 4% and 9% compared to the process without acoustic treatment.

[0111] In another example, Versum Materials CopperReady3930® commercial copper paste (according to manufacturer specifications) mixed with water and hydrogen peroxide was used. Dupont IC1010® concentric trench pads were also used on an 800-mm rotary platen. Saesol 4DNS80AMC1 diamond dressing discs were also used in in-situ dressing mode. For each wafer, a 200-mm control copper wafer was polished for 30 seconds. The process pressure ranged between 1.5 and 2.0 PSI. The slide speed was set at 1.5 m / s. The paste flow rate was kept constant at 150 cc / min. Without sonic treatment, the average copper removal rates based on polishing a total of 6 wafers at polishing pressures of 1.5 and 2.0 PSI were 8,403 and 11,006 Å / min, respectively. With an acoustic processing energy of 1.0 W / cm² and a 5-minute incubation time, the copper removal rates of four wafers at polishing pressures of 1.5 and 2.0 PSI increased to 8,806 and 11,789 Å / min, respectively. This represents an average removal rate increase of 5% and 7% compared to the process without acoustic processing. When the acoustic setpoint was 2.0 W / cm² and a 5-minute incubation time, the average copper removal rates of four wafers at polishing pressures of 1.5 and 2.0 PSI also increased to 9,134 and 12,075 Å / min, respectively. This represents an increase in removal rate of 9% and 10% compared to the process without acoustic processing.

[0112] In another example, Versum Materials CopperReady 3935® commercial copper paste (according to manufacturer specifications) mixed with water and hydrogen peroxide was used. Dupont IC1010® concentric trench pads were also used on an 800-mm rotary platen. Saesol 4DNS80AMC1 diamond dressing discs were also used in in-situ dressing mode. For each wafer, a 200-mm control copper wafer was polished for 30 seconds. The process pressure ranged between 1.5 and 2.0 PSI. The slide speed was set at 1.5 m / s. The paste flow rate was kept constant at 150 cc / min. Without sonic treatment, the average copper removal rates based on polishing a total of four wafers at polishing pressures of 1.5 and 2.0 PSI were 8,365 and 10,748 Å / min, respectively. When the acoustic setpoint was set at 2.0 W / cm² and a 5-minute incubation time was used again, the average copper removal rates based on polishing of a total of four wafers under polishing pressures of 1.5 and 2.0 PSI increased to 9,017 and 12,066 Å / min, respectively. This represents an increase in removal rate of 8% and 12% compared to the process without acoustic processing.

[0113] In another example, Versum Materials DP1236® tungsten paste (according to manufacturer's specifications) mixed with hydrogen peroxide was used. Dupont IC1000® XY trench pads were used on an 800-mm rotary platen. Before polishing each wafer, a Saesol 4DNS80AMC1 diamond dressing disc in non-in-situ dressing mode was used for 30 seconds. For each wafer, a 200-mm control tungsten wafer was polished for 60 seconds. The process pressure was 4.0 PSI. The slide speed was set at 2.0 m / s. The paste flow rate was kept constant at 125 cc / min. Without acoustic treatment, the average tungsten removal rate based on polishing a total of 6 wafers was 2,277 Å / min. When the acoustic energy was set to 2.0 W / cm² and a 5-minute incubation time was used, the tungsten removal rate based on a total of 6 wafers was 2,423 Å / min. This represents a 7% increase in removal rate.

[0114] In another example, Versum Materials DP1236® tungsten paste (according to manufacturer's specifications) mixed with hydrogen peroxide was used. Dupont IC1000® XY trench pads were used on an 800-mm rotary platen. Before polishing each wafer, a Saesol 4DNS80AMC1 diamond dressing disc in non-in-situ dressing mode was used for 30 seconds. For each wafer, a 200-mm control tungsten wafer was polished for 60 seconds. The process pressure was 3.0 PSI. The slide speed was set at 1.6 m / s. The paste flow rate was kept constant at 125 cc / min. Without acoustic treatment, the average tungsten removal rate based on polishing a total of 4 wafers was 1,646 Å / min. When the acoustic energy was set to 2.0 W / cm² and a 5-minute incubation time was used again, the tungsten removal rate based on polishing a total of 4 wafers was 1,803 Å / min. This represents a 10% increase in removal rate.

[0115] In another example, Versum Materials DP1142® tungsten paste (according to manufacturer's specifications) mixed with hydrogen peroxide was used. Dupont IC1000® XY trench pads were used on an 800-mm rotary platen. Before polishing each wafer, a Saesol 4DNS80AMC1 diamond dressing disc was operated in non-in-situ dressing mode for 30 seconds. For each wafer, one or more 200-mm control tungsten wafers were polished for 45 seconds. The process pressure was kept constant at 4.0 PSI. The slide speed was also kept constant at 1.6 m / s. The paste flow rate was kept constant at 125 cc / min. Without ultrasonic treatment, the tungsten removal rate was 1,928 Å / min. With ultrasonic treatment of the paste, the paste was continuously ultrasonically treated as it flowed through the ultrasonic generator bowl and towards the polisher tube. The incubation time of the paste in this continuous ultrasonic generator was estimated to be less than 10 seconds. That is, the slurry was not kept stagnant (or exhibiting any kind of holding pattern) in the reactor for any period of time. When the acoustic setpoint was 1.25 W / cm², the average tungsten removal rate was 2,112 Å / min. This represents a 10% increase in the removal rate.

[0116] In another example, Versum Materials Cu3930® copper paste (according to manufacturer's specifications) mixed with hydrogen peroxide was used. Dupont IC1000® XY trench pads were used on a 500-mm rotary platen. Before polishing each wafer, a Saesol 4DNS80AMC1 diamond dressing disc in non-in-situ dressing mode was used for 30 seconds. For each wafer, a 200-mm control copper wafer was polished for 60 seconds. Process wafer and holding ring pressures were kept constant at 1.5 and 1.7 PSI, respectively. The slide speed was also kept constant at 0.5 m / s. The paste flow rate was kept constant at 160 cc / min. Without sonic treatment, the copper removal rate was 4,909 Å / min. In a polishing process with ultrasonic slurry treatment, two ultrasonic generator bowls are used in parallel, each with a slurry flow rate of 80 cc / min, resulting in a total slurry flow rate of 160 cc / min. When the acoustic energy of each ultrasonic generator bowl is set to 2.0 W / cm² and a 5-minute incubation time is used, the average copper removal rate increases to 6,221 Å / min. This represents a 27% increase in removal rate compared to a process without ultrasonic treatment.

[0117] In another example, Versum Materials Cu3930® copper paste (according to manufacturer's specifications) mixed with hydrogen peroxide was used. Dupont IC1000® XY trench pads were used on a 500-mm rotary platen. Before polishing each wafer, a Saesol 4DNS80AMC1 diamond dressing disc in non-in-situ dressing mode was used for 30 seconds. For each wafer, a 200-mm control copper wafer was polished for 20 seconds. The process wafer and holding ring pressures for the first polishing formulation were kept constant at 1.5 and 1.7 PSI, respectively, and the slide speed was kept constant at 0.5 m / s. The process wafer and holding ring pressures for the second polishing formulation were kept constant at 2.5 and 2.7 PSI, respectively, and the slide speed was kept constant at 1.6 m / s. The paste flow rate for both polishing formulations was kept constant at 160 cc / min. Without ultrasonic treatment, the average copper removal rates of the first and second polishing formulations were 5,703 and 15,552 Å / min, respectively. In the polishing process with ultrasonic slurry treatment, two ultrasonic generator bowls were used in parallel, each with a slurry flow rate of 80 cc / min, resulting in a total slurry flow rate of 160 cc / min. When the acoustic energy of each ultrasonic generator bowl was set to 2.0 W / cm² and a 5-minute incubation time was used, the average copper removal rates of the first and second polishing formulations increased to 7,397 and 19,383 Å / min, respectively. This represents an increase in removal rate of 30% and 25% compared to the process without ultrasonic treatment.

[0118] In another example, Versum Materials DP1236® tungsten paste (according to manufacturer's specifications) mixed with hydrogen peroxide was used. Dupont IC1000® XY trench pads were used on a 500-mm rotary platen. Before polishing each wafer, a Saesol 4DNS80AMC1 diamond dressing disc in non-in-situ dressing mode was used for 30 seconds. For each wafer, a 200-mm control tungsten wafer was polished for 45 seconds. Process wafer and holding ring pressures were kept constant at 3 and 6 PSI, respectively. The slide speed was also kept constant at 1.6 m / s. The paste flow rate was kept constant at 80 cc / min. Without ultrasonic treatment, the tungsten removal rate was 3,197 Å / min. In the polishing process with paste ultrasonic treatment, two ultrasonic generator bowls were used in parallel, each with a paste flow rate of 40 cc / min, resulting in a total paste flow rate of 80 cc / min. When the acoustic energy of each ultrasonic generator cup was set to 2.0 watts per square centimeter and a 5-minute incubation time was used, the average tungsten removal rate increased to 3,395 angstroms per minute. This represents a 6% increase in removal rate compared to a process without ultrasonic treatment.

[0119] While the foregoing has described the best practices and / or other examples, it should be understood that various modifications may be made therein, and the subject matter disclosed herein can be implemented in various forms and examples, and the teachings can be applied to many applications, of which only a few are described herein. The following claims are intended to be any and all applications, modifications and variations that, as claimed, fall within the true scope of the teachings.

[0120] 10: CMP Slurry Processing System 12: Data Analysis and Reporting Computer 20: Wafer; Substrate 17: Slurry 17A: Modified slurry 102: Wafer polishing equipment; polishing system 103: Polishing pad; disc 104: Polishing head 110: Slurry application system 112: Light Wave Energy Source 113: Sound Wave Energy Source 114: Slurry holding container 116: Additive retention equipment 120: Special Purpose Processor 122: Controller 131: Material Additives 133: Wave Energy Source 200: Method 202: Steps 204: Steps 206: Steps 210: CMP Method 212: Steps 214: Steps 215: Steps 216: Steps 220: CMP Method 222: Steps 223: Steps 224: Steps 226: Steps 230: CMP Method 232: Steps 233: Steps 234: Steps 236: Steps 240: CMP Method 242: Steps 243: Steps 244: Steps 246: Steps 300: CMP Slurry Processing System 302: Storage container shell 304: Sonic agitator 306:Piping 308: Power generator; RF power generator 311: Non-rolled entrance area; entrance 313: Rolled section 320: Deionized water 321: Non-coiled outlet area; water level 400: Slurry processing equipment 401: Sliding fit element 401A: First Fixture Section 401B: Second clamping part 402: Container shell 403: Opening 404: Recessed O-ring 405: Shear ring 406: Winged Nut 407: Trench 408: Internal 409: Cover element 410: Cover sealing system 411: Inlet pipe 412: Export; Export pipe 413: Ventilation tube 414: Valve 415: Nuts 418: Gas inlet pipe 421: Connector 430: Transducer housing 431: Sound resonator or other sound energy generating device 422: Surrounding Area 423: Rod 424: Hemispherical interior 700: Bar Chart 800: Slurry Injection System 808: Bottom section 809: Kong 900: Method 902: Steps 904: Steps 906: Steps 910: Steps 912: Steps; Light Generation System 914: Steps 916: Steps 918: Steps 920: Method 922: Steps 924: Steps 926: Steps 928: Steps

[0121] none

Claims

1. A chemical mechanical planarization (CMP) method comprising: providing a CMP slurry source having a material additive; modifying the CMP slurry source by directing a wave energy source toward the CMP slurry source to form a modified CMP slurry, wherein modifying the CMP slurry source includes modifying the material additive to enhance substrate material removal properties; applying a fluid of the modified CMP slurry to a wafer polishing apparatus, a substrate positioned at the wafer polishing apparatus; modifying a passivation layer of the substrate by chemically reacting with the modified CMP slurry, wherein modifying the passivation layer alters the passivation layer to increase the removal rate at a given polishing pressure, or to maintain the removal rate at a lower polishing pressure; and performing a polishing operation on the substrate, wherein the polishing operation is performed at the given polishing pressure or the lower polishing pressure.

2. The CMP method of claim 1, wherein the wave energy source is a source of at least one of mechanical or electromagnetic wave energy.

3. The CMP method of claim 2 further includes: modifying the CMP slurry source by applying the material additive to the CMP slurry source.

4. The CMP method of claim 3, wherein the material additive is applied to the CMP slurry source before directing the source of at least one of mechanical or electromagnetic energy to the CMP slurry source.

5. The CMP method of claim 3, wherein when the source of at least one of mechanical or electromagnetic energy is directed to the CMP slurry source, the material additive is simultaneously applied to the CMP slurry source.

6. The CMP method of claim 3, wherein the CMP slurry source is modified by directing the source of at least one of mechanical or electromagnetic energy to the wafer polishing apparatus and by applying the material additive to the CMP slurry source at the wafer polishing apparatus.

7. The CMP method of claim 3, wherein the material additive is modified by at least one of mechanical or electromagnetic energy.

8. The CMP method of claim 2, wherein the CMP slurry source is modified by a source of mechanical wave energy within a sealed container, and wherein applying the fluid of the modified CMP slurry to the wafer polishing apparatus includes discharging the modified CMP slurry from the sealed container to the wafer polishing apparatus.

9. The CMP method as described in claim 8, wherein the sealed container comprises: A container housing having an opening leading to an interior of the container housing, the interior being constructed and configured to hold the CMP slurry source; a cap sealing system forming a fluid seal above the opening in the container housing; and an inlet and an outlet extending through the cap sealing system to form a continuous slurry flow path from the inlet through the interior of the container housing and further from the outlet to a wafer polishing apparatus.

10. The CMP method of claim 8, wherein the mechanical wave energy is acoustic energy generated inside the sealed container.

11. The CMP method of claim 8, wherein the electromagnetic wave energy is light generated along the fluid of the CMP slurry source between the sealed container and the wafer polishing equipment.

12. The CMP method of claim 11, wherein the mechanical wave energy is the acoustic energy applied to the fluid of the CMP slurry source after the light is applied to the fluid of the CMP slurry source.

13. The CMP method of claim 11, wherein the mechanical wave energy is the acoustic energy of the fluid of the CMP slurry source applied before the light is applied to the fluid of the CMP slurry source.

14. The CMP method of claim 2, wherein the source of at least one of mechanical or electromagnetic wave energy includes both acoustic energy and light, and wherein the acoustic energy is directed to the CMP slurry source before the light is directed to the CMP slurry source.

15. The CMP method of claim 2, wherein the source of at least one of mechanical or electromagnetic wave energy includes both acoustic energy and light energy simultaneously applied to the CMP slurry source.

16. The CMP method of claim 2, wherein the source of at least one of mechanical or electromagnetic wave energy includes both acoustic energy and light, and wherein the acoustic energy is directed to the CMP slurry source after the light is directed to the CMP slurry source.

17. The CMP method of claim 2, further comprising: positioning a slurry injection system relative to the substrate rotating on the wafer polishing apparatus for discharging the CMP slurry source.

18. A slurry processing system comprising: a container housing having an opening leading to an interior of the container housing, the interior being configured and configured to hold a chemical mechanical planarization (CMP) slurry source having a material additive; a cap sealing system forming a fluid seal over the opening of the container housing; an inlet and an outlet extending through the cap sealing system to form a continuous slurry flow path from the inlet through the interior of the container housing and further extending from the outlet to a wafer polishing apparatus; and an energy generating device directing a source of at least one of mechanical or electromagnetic wave energy toward the CMP slurry flowing along the continuous slurry flow path to modify the CMP slurry having the material additive, including modifying the material additive to enhance substrate material removal properties; The passivation layer of a substrate is modified by chemical reaction with a modified CMP slurry, wherein the modification of the passivation layer changes the passivation layer to increase the removal rate at a given polishing pressure or maintain the removal rate at a lower polishing pressure; and wherein a polishing operation is performed on the substrate at the given polishing pressure or the lower polishing pressure.

19. The slurry handling system of claim 18, wherein the cap sealing system comprises: A retaining ring element through which the inlet and the outlet extend; A shear ring positioned in a groove around the container shell, the shear ring forming a seal-tight interface with the retaining ring element; and a sliding fit element forming a seal-tight interface with the retaining ring element.

20. The slurry handling system of claim 19, wherein the sliding fit element includes a first clamping portion and a second clamping portion, wherein at least one of the first clamping portion and the second clamping portion includes a rod configured for insertion into a hole in the other of the first clamping portion and the second clamping portion, and wherein the cap sealing system includes a wing nut positioned around the rod in the hole to generate a force that couples the first clamping portion and the second clamping portion together around the retaining ring element and around the shear ring of the container housing.

21. The slurry handling system of claim 20, further comprising a vent pipe coexisting with the inlet and the outlet, the vent pipe extending through the cap sealing system to allow trapped air to escape from the container housing.

22. The slurry processing system of claim 20, further comprising a gas inlet pipe for injecting or impregnating oxygen or ozone.

23. The slurry processing system of claim 20, wherein the sliding fit element has a hemispherical interior formed by the first clamping portion and the second clamping portion, the hemispherical interior being threaded to form a seal when coupled with the retaining ring element.

24. The slurry processing system of claim 18, wherein the CMP slurry is configured to be chemically connected to a substrate on the wafer polishing apparatus, wherein an upper layer of the substrate is formed of copper, tungsten, polysilicon, silicon dioxide, aluminum, carbon-doped silicon dioxide, black diamond, silicon nitride, tantalum, tantalum nitride, titanium, titanium nitride, cobalt, gallium nitride, ruthenium, silicon carbide, or combinations thereof or alloys thereof, the upper layer being modified or removed by chemically reacting with one of the modified CMP slurries.

25. The slurry processing system of claim 18, wherein the energy generating device includes a sound wave generating mechanism having one or more transducers that generates sound energy to acoustically activate the CMP slurry along the continuous slurry flow path.

26. The slurry processing system of claim 18, wherein the energy generating device includes a light source configured and arranged to irradiate the CMP slurry.

27. The slurry processing system of claim 26, wherein the CMP slurry comprises at least one ligand complexing agent and a metal to form a metal-ligand complex by irradiation of the light source to oxidize the ligand.

28. The slurry processing system of claim 27, wherein the ligand ligand comprises at least one of tyrosine, phenylalanine, tryptophan, histidine, and glycine.

29. The slurry processing system of claim 18, wherein the CMP slurry comprises a polymer-based nanocomposite slurry comprising a macromolecular polymer and a composite additive.

30. The slurry processing system of claim 18, wherein the energy generating device includes a first device employing megahertz energy and a second device employing light waves, the first device and the second device being directed to the CMP slurry in chemical contact with a SiC substrate to remove a surface layer of the SiC substrate during a polishing operation performed by the wafer polishing equipment.

31. The slurry processing system of claim 18, further comprising a slurry injection system positioned relative to the wafer polishing apparatus to output the CMP slurry source at a substrate rotating on the wafer polishing apparatus.

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