Method and apparatus for substrate cleaning in stacked die mixed bonding process

Abstract

The brush cartridge cleaning module is introduced as part of a pre-treatment process flow in an integrated hybrid bonding platform. It addresses the technical problem of achieving high levels of cleanliness on the front and back side surfaces of the die, in particular by removing residues and particles caused by back abrasive and dicing tapes. The brush cartridge cleaning module efficiently removes refractory residues and particles both chemically and mechanically, resulting in a cleaned and passivated surface without causing watermarks, scratches, corrosion or surface roughness. This disclosed method improves bonding yield and provides significant advantages over existing methods in die stack hybrid bonding applications.

Description

Technical Field

[0001] The embodiments of this disclosure generally relate to semiconductor manufacturing, and more specifically, to a hybrid bonding platform incorporating a brush module for cleaning substrates in die stack bonding applications. Background Technology

[0002] Semiconductor components are widely used in a wide range of electronic products and systems, from consumer electronics to industrial and military applications. With the continued growth in demand for increasingly complex and miniaturized electronic devices, the semiconductor manufacturing industry has been seeking to develop advanced packaging technologies to integrate multiple chips or layers within a single device. Die stacking (a method of vertically stacking chips on top of each other) is one such advanced packaging technology that offers advantages such as enhanced functionality, reduced form factor, and improved performance.

[0003] In die stacking bonding applications, the cleanliness of the die surface is crucial for achieving high bonding yields and reliability. Contaminants such as residues and particles introduced during wafer handling, back grinding, dicing, or other manufacturing steps can negatively impact the bonding process, leading to defects or failures in the final semiconductor device. To address this issue, various cleaning methods have been developed to remove contaminants from the die surface prior to bonding.

[0004] One such cleaning method is wet cleaning, which typically involves using liquid chemicals (such as solvents, acids, or alkalis) to remove contaminants from the grain surface. Wet cleaning processes can employ mega-frequency ultrasonic or atomizer cleaning technologies to enhance contaminant removal. However, these wet cleaning methods have limitations, particularly in their ability to remove stubborn residues and particles caused by back-abrasive or scuffing tapes from the grain surface. Furthermore, wet cleaning processes can sometimes lead to undesirable side effects such as watermarks, scratches, corrosion, or surface roughness, which can negatively impact the performance of the combined process and equipment.

[0005] In related technologies, various alternative cleaning methods have been proposed to overcome the limitations of wet cleaning. These methods include dry cleaning, plasma cleaning, and laser cleaning. While these alternative cleaning methods offer certain advantages, they may not be effective in all cases or compatible with all substrate materials, and they may also have their own limitations and drawbacks.

[0006] In light of the foregoing, there remains a need for an improved cleaning method and system for die-to-die bonding applications that effectively removes residues and particles from the die surface without causing undesirable side effects, and is suitable for use in various bonding embodiments, such as die-to-wafer and wafer-to-wafer bonding. This need is met by providing an integrated hybrid bonding platform that incorporates a brush cassette cleaning module for enhanced substrate surface cleaning. Summary of the Invention

[0007] The embodiments described herein provide a hybrid platform for addressing the aforementioned needs, a brush cassette assembly for cleaning substrates, and a process for manufacturing stacked semiconductor structures.

[0008] In a first aspect, embodiments of the present disclosure provide a hybrid bonding platform comprising: a substrate transport system configured to transport a substrate through a platform; a brush cleaning module configured to clean the surface of the substrate by removing residues and particles; a bonding module configured to bond the substrate grains; and a controller configured to control the substrate transport system, the brush cleaning module, and the bonding module.

[0009] In a second aspect, embodiments of the present disclosure provide a brush cassette assembly for cleaning a substrate in a hybrid bonding platform, the brush cassette assembly comprising: a housing configured to surround the substrate; a plurality of brushes configured to engage with a surface of the substrate; and a cleaning agent delivery system configured to deliver cleaning agent to the plurality of brushes.

[0010] In a third aspect, embodiments of the present disclosure provide a process for manufacturing a stacked semiconductor structure, the process comprising: providing a substrate comprising a plurality of grains; cleaning the surface of the substrate using a brush cleaning module to remove residues and particles; and using a hybrid bonding process to bond the grains of the substrate.

[0011] These and other aspects, features, and advantages of this disclosure will become apparent from the following detailed description taken in conjunction with the accompanying drawings. Attached Figure Description

[0012] To gain a more detailed understanding of the features described above in this disclosure, reference can be made to one or more embodiments, some of which are illustrated in the accompanying drawings. However, it should be noted that the drawings illustrate only one or more of several embodiments; therefore, the one or more embodiments provided in the drawings should not be considered as limiting the most broad interpretation of the scope of detail. Other effective embodiments that may be described in the detailed description should be considered as part of the contemplated scope.

[0013] Figure 1 This is a schematic diagram of an exemplary hybrid platform according to one or more embodiments.

[0014] Figure 2A It is based on one or more embodiments in Figure 1 An isometric view of an example of a brush cleaner used in a hybrid platform.

[0015] Figure 2B According to one or more embodiments Figure 2A A top view of the brush cleaner.

[0016] Figure 2C This is an isometric view of a scrubbing device disposed within a brush cleaner according to one or more embodiments, in a loaded state (where a substrate is loaded).

[0017] Figure 2D This is an isometric view of a scrubbing device disposed within a brush cleaner in an idle state (without a substrate loaded), according to one or more embodiments.

[0018] Figure 3 This is a flowchart illustrating an exemplary process for manufacturing a stacked semiconductor structure according to one or more embodiments.

[0019] To facilitate understanding and better appreciation of the scope described, in some cases, where possible, the same or associated element symbols are used to denote the same or similar elements common to the figures. Those skilled in the art will appreciate that elements and features of one embodiment may be advantageously incorporated into one or more other embodiments without further description. Detailed Implementation

[0020] The embodiments described herein provide an improved method and system for cleaning substrates in die stacking bonding applications by incorporating a brush cassette module into an integrated hybrid bonding platform for advanced packaging. The brush cassette module effectively removes residues and particles from the die surface without causing watermarks, scratches, corrosion, or surface roughness, thereby improving bonding yield.

[0021] Figure 1A schematic diagram of an exemplary integrated hybrid bonding platform 100 for advanced packaging according to an embodiment of the present disclosure is shown. The hybrid bonding platform 100 is designed to facilitate precise and efficient bonding of semiconductor devices through automated processes. In one embodiment, the hybrid bonding platform 100 includes an equipped front-end module (EFEM) 102, surface preparation modules 104 and 106, a bonding module 108, and a system controller 112. The equipped front-end module (EFEM) 102 is responsible for loading and unloading substrates from a plurality of substrate cassettes 110. The surface preparation modules 104 and 106 are designed to clean and activate the substrates in preparation for bonding. The bonding module 108 is responsible for performing a hybrid bonding process involving bonding a source substrate 110A to a target substrate 110B. The system controller 112 manages and coordinates the operation of the various modules within the hybrid bonding platform 100.

[0022] As disclosed in the integrated hybrid bonding platform 100, the equipped front-end module (EFEM) 102 includes a support structure configured to accommodate multiple substrate cassettes 110 adapted to hold source substrates 110A and target substrates 110B. The EFEM 102 further includes a housing 111 surrounding a chamber that provides a controlled environment for handling and processing the substrates. The enclosed chamber is configured to maintain the cleanliness and integrity of the substrates during the bonding process by mitigating the risk of contamination and exposure to external factors. Additionally, the equipped front-end module 102 is equipped with one or more factory interface robots 113 operatively connected to the chamber and configured to transfer substrates between the substrate cassettes and various modules of the hybrid bonding platform 100. The factory interface robots 113 ensure precise and efficient movement of substrates through the system by automating substrate transfer, thereby contributing to the overall efficiency of the hybrid bonding process.

[0023] Surface preparation module 104 is specifically designed to perform a series of cleaning and activation steps on a substrate (such as a semiconductor wafer) using an integrated and automated system. In one embodiment, surface preparation module 104 includes an automated modular host (AMM) 130A, a brush holder cleaning module 140A, a wet cleaning module 150A, a degassing module 160A, and a plasma module 170A.

[0024] The Automated Modular Mainframe (AMM) 130A serves as the central hub of the system, coordinating substrate transfer between different sub-modules. This mainframe utilizes a substrate transfer robot to move substrates between process stations, ensuring precise handling and minimizing the risk of contamination or damage. The AMM 130A includes a wafer aligner 132A and an in-line metering system 134A. These components work together to ensure proper substrate alignment and verify surface properties before and after surface preparation processes. The wafer aligner 132A is configured for precise substrate alignment, ensuring accurate positioning according to the requirements of the bonding process. The in-line metering system 134A is suitable for measuring and verifying substrate surface properties, including cleanliness, activation level, and other relevant parameters, before and after the cleaning and activation steps performed by the surface preparation module 104.

[0025] The brush box cleaning module 140A provides mechanical cleaning of substrate surfaces, using brushes or other mechanical scrubbing components to remove particles and contaminants. This module can be customized to use different brush materials, rotation speeds, and cleaning chemicals to achieve the desired level of cleanliness.

[0026] The wet cleaning module 150A is responsible for the chemical cleaning of the substrate, using various liquid cleaning agents to remove contaminants that may be difficult to remove by mechanical components. These cleaning agents may include deionized water, acids, alkalis, or other specialized chemicals, depending on the specific requirements of the process and the substrate material.

[0027] The degassing module 160A is configured to degas the substrate by removing residual liquids, gases, and contaminants that may have been adsorbed or trapped on the substrate surface during previous processing steps. This step is crucial to ensuring that the substrate surface is free of contaminants that could interfere with subsequent processing steps.

[0028] The Plasma Module 170A is designed and configured for efficient and effective radical / plasma RPS / RF cleaning or activation processes. The Plasma Module 170A includes a remote plasma source (RPS) that can be selectively positioned on the top, sidewalls, or any combination thereof within the chamber, providing flexibility in RPS placement. The RPS is further equipped with engineered hardware components, such as baffles and / or diffusers, which contribute to the uniform distribution of gas or radicals within the chamber, thereby ensuring consistent process control and reproducibility.

[0029] In one or more embodiments, the plasma module 170A is configured to operate in a variety of RPS / RF processes, including (but not limited to) RPS, RF plasma, RF-assisted RPS, RPS-assisted RF plasma, or intermittent RPS / RF processing. This versatility enables customized cleaning or activation processes to be implemented depending on the specific substrate material and the combined application employed.

[0030] The plasma module 170A is further adapted to utilize a range of RPS / RF cleaning or activating gaseous chemicals, including (but not limited to) H2, N2, Ar, He, NH3, NF3, and CDA. This compatibility with a variety of gaseous chemicals allows the plasma module 170A to adapt to a variety of substrate materials and surface conditions, thereby optimizing surface preparation for hybrid bonding processes.

[0031] Surface preparation module 106 may include similar or alternative sub-modules as needed to address specific substrate cleaning and activation requirements. In general, surface preparation modules 104 and 106 ensure that the source substrate 110A and target substrate 110B are thoroughly cleaned and activated, preparing them for subsequent bonding processes within the integrated hybrid bonding platform 100.

[0032] The bonding module 108 is responsible for performing the bonding of the die from the source substrate 110A to the target substrate 110B after surface preparation. This module plays a critical role in ensuring the high precision and reliability required for semiconductor device assembly. The bonding module 108 includes an automated modular host (AMM) 130C, a UV module 180, and one or more bonders 190. The automated modular host 130C acts as a central control unit, managing and coordinating the operation of the UV module 180 and the bonders 190 to ensure efficient and accurate die bonding. The UV module 180 is responsible for weakening the adhesive that holds the die to the source substrate 110A. By exposing the tape frame to ultraviolet light, the molecular structure of the adhesive changes, reducing its strength and allowing easy release of the die without damage. Finally, the bonders 190 perform the picking, flipping, placement, and bonding of the die. By using a highly precise robotic system, the bonders 190 ensure precise alignment and positioning of the die throughout the hybrid bonding process. It picks up dies from source substrate 110A, flips them to the correct orientation, accurately places them onto target substrate 110B, and initiates a bonding process, which may involve pressure, heat, or both. The terms substrate and wafer are used interchangeably throughout the disclosure provided herein to describe a workpiece containing multiple dies on which one or more methods described herein will be performed.

[0033] A system controller 112 (such as a programmable computer) is coupled to the integrated hybrid platform 100 for controlling one or more components therein. In one embodiment, the system controller 112 may control wafer handling and transfer between different processing modules to execute a process sequence. In another embodiment, the system controller 112 may control the operation of a brush cassette cleaning module 140, which will be further described below. In operation, the system controller 112 enables the acquisition of data and feedback from various components to coordinate processing within the integrated hybrid platform 100. The system controller 112 includes a programmable central processing unit (CPU) 114, which may operate in conjunction with a memory 116 (e.g., non-volatile memory) and support circuitry 118. The support circuitry 118 (e.g., cache, frequency circuitry, input / output subsystems, power supplies, etc., and combinations thereof) is typically coupled to the CPU 114 and to various components within the integrated hybrid platform 100.

[0034] In operation, the hybrid bonding process begins with loading a source substrate 110A and a target substrate 110B onto a front-end module 102 via one or more factory interface robots 113. The substrates 110A and 110B (which include multiple dies) are then transported via an integrated hybrid bonding platform 100 through automated modular hosts 130A and 130B.

[0035] Next, wafer aligners 132A and 132B are used to align substrates 110A and 110B to ensure accurate die placement during the bonding process. The aligned substrates 110A and 110B are then transported to brush cartridge cleaning modules 140A and 140B, where residues and particles caused by back-abrasion tape or dicing tape are removed from the substrate surfaces. Brush cartridge cleaning modules 140A and 140B may include a housing configured to surround substrates 110A and 110B, a plurality of brushes configured to engage with the substrate surfaces, and a cleaning agent delivery system configured to deliver cleaning agent to the plurality of brushes.

[0036] After the initial brush box cleaning, substrates 110A and 110B undergo wet cleaning steps in wet cleaning modules 150A and 150B, which may involve delivering cleaning and rinsing fluids and using mega-frequency ultrasonic or atomizer cleaning methods to remove contaminants from the substrate surface.

[0037] Following wet cleaning, substrates 110A and 110B are transported to degassing modules 160A and 160B, where unwanted gases, moisture, or contaminants are removed from the surface of the substrate or die-containing workpiece. The degassing process typically involves heating the substrate or workpiece to a specific temperature, causing contaminants, trapped gases, or moisture to evaporate or desorb from the surface. In some cases, the process may also involve applying a vacuum or inert gas to facilitate contaminant removal. Proper degassing can improve adhesion, reduce defects, and enhance the overall performance of semiconductor devices, particularly in applications involving mixed die stacking.

[0038] Next, the degassed substrates 110A and 110B are treated in plasma modules 170A and 170B for surface activation and further cleaning. During the plasma activation process, the surface of the grain or wafer is exposed to plasma containing charged particles such as ions and electrons. These high-energy ions bombard the surface, thereby removing contaminants and activating the surface by generating reactive sites that increase surface energy and wettability. This activation process makes the surface more hydrophilic and chemically reactive, thus promoting better adhesion and bonding quality in hybrid bonding processes.

[0039] Substrates 110A and 110B are then transferred to the chamber of an automated modular host 130C and subsequently processed in a UV module 180 coupled to the automated modular host 130C to facilitate the release of the die from the adhesive tape frame prior to bonding. The UV module operates by exposing the tape frame holding the die to ultraviolet light. High-energy ultraviolet photons interact with the adhesive material, causing a change in the molecular structure of the adhesive. This change results in a decrease in adhesive strength, allowing the die to be easily released from the tape frame.

[0040] Finally, a hybrid bonding process performed by either bonder 190A or bonder 190B is used to bond the dies of substrates 110A and 110B. In bonder 190, the process of bonding the source substrate 110A to the target substrate 110B begins with the precise alignment of the dies on the source substrate 110A with the corresponding bonding sites on the target substrate 110B. This alignment is achieved using advanced alignment systems, such as high-resolution cameras and pattern recognition algorithms, which precisely align the dies or copper interconnects on the substrate and the surrounding dielectric material.

[0041] Once alignment is achieved, the bonding module 190 uses a pick-and-place mechanism to pick up individual dies from the source substrate 110A. This mechanism may include a vacuum-based gripping system or other suitable mechanism for handling semiconductor dies. The picked-up die is then flipped and placed close to the target substrate 110B.

[0042] Prior to the actual bonding step, the bonding module 190 can apply a pre-bonding force to ensure close contact between the surfaces of the source and target substrates. This pre-bonding force ensures that the copper interconnects and dielectric materials are very close, which is crucial for establishing reliable electrical connections and minimizing defects in the bonding structure.

[0043] The bonding module 190 then applies controlled forces and temperatures to the source and target substrates to initiate the bonding process. The forces and temperatures applied during the bonding process depend on the specific bonding technique used, such as thermoforming or direct bonding. The bonding process may involve the formation of molecular bonds between dielectric layers and the fusion of copper pads to establish an electrical connection.

[0044] Throughout the bonding process, the bonder module 190 is equipped with sensors and a feedback system to monitor key parameters such as force, temperature, and alignment accuracy. This real-time monitoring allows for fine-tuning and control of the bonding process to ensure optimal bonding performance and yield.

[0045] After the bonding process is completed, the bonded dies form a stacked semiconductor structure, wherein the source substrate 110A is bonded to the target substrate 110B. The bonder module 190 then repeats this process on the remaining dies on the source substrate 110A, thereby iteratively building a vertically integrated stack of dies or substrates.

[0046] The bonding process performed by the bonding module 190 ensures optimal electrical connections and minimal defects, resulting in high-performance, compact, and versatile semiconductor devices.

[0047] In a die-to-wafer bonding embodiment, individual dies are bonded to a receiving wafer, which may contain pre-patterned bonding pads or other structures to facilitate the bonding process. The dies and receiving wafers first undergo cleaning, degassing, plasma treatment, and UV curing steps as described previously. The bonder 190 is configured to pick up the individual dies, align them with the receiving wafer, and bond them using a hybrid bonding process. This process may involve aligning the bonding pads on the die with corresponding bonding pads on the receiving wafer, and applying pressure and heat to form a strong bond between the die and the receiving wafer.

[0048] One or more embodiments described herein relate to simultaneously bonding multiple dies from a donor wafer to a host wafer. In this approach, the entire die array is aligned and bonded to the host wafer in a single step. In other embodiments, individual dies from the donor wafer are bonded to the host wafer one at a time. In this approach, each die is independently picked up, aligned, and bonded to the host wafer.

[0049] In wafer-to-wafer bonding embodiments, two wafers with matching patterns are joined together to form a stacked wafer structure. The wafers are first subjected to cleaning, degassing, plasma treatment, and UV curing steps as described previously. The bonder 190 is configured to align the wafers, ensuring precise alignment of bonding pads or other structures on each wafer. The aligned wafers are then joined together using a hybrid bonding process, which may involve applying pressure and heat to form a strong bond between the two wafers.

[0050] By incorporating a brush cleaning module into an integrated hybrid bonding platform, embodiments of this disclosure provide an effective and efficient method for removing residues and particles from die surfaces in die stacking bonding applications, resulting in improved bonding yields and reliability in semiconductor device manufacturing. Embodiments of this disclosure are applicable to a variety of bonding implementations, including die-to-wafer and wafer-to-wafer bonding, thereby providing flexibility in advanced packaging applications.

[0051] Figure 2A This is an isometric view of a brush cleaner 200 that can be utilized in the integrated hybrid platform 100 described above. For ease of discussion, the cover portion of the brush cleaner 200, including the door, has been omitted. Figure 2A and Figure 2B Remove. Figure 2A The brush cleaner 200 shown may be a scrubber-type brush holder vertical cleaner. The example brush cleaner 200 includes a groove 205 supported by a first support 225 and a second support 230. The brush cleaner 200 includes actuators 235, each actuator 235 coupled to a cylindrical roller 228 located inside the groove 205 (e.g., ...). Figure 2B (As shown). Actuators 235 may each include a drive motor, such as a direct-drive servo motor, which is adapted to rotate about axes A' and A'' ( Figure 2B (As shown) rotate the corresponding cylindrical roller. Each actuator 235 is coupled to a controller 112, which is adapted to control the rotational speed of the cylindrical roller.

[0052] Link 210 and actuator 245 are configured to allow the cylindrical roller 228 located inside the groove 205 to be positioned relative to the main surface of the substrate 201. Figure 2B (As shown in the diagram) the actuator 245 is coupled to the controller 112 to control the movement of the linkage 210 relative to the substrate disposed between the cylindrical rollers 228. Simultaneous movement. Except for the substrate 201. In operation, the first support 225 and the second support 230 can move simultaneously relative to the base 240. This movement allows the first and second cylindrical rollers 228 to move as shown in the diagram. Figure 2C As shown, close to the substrate 201, or with the first and second cylindrical rollers 228 as... Figure 2D The spacing shown allows for insertion and / or removal of the substrate 201 from the brush cleaner 200.

[0053] Figure 2B yes Figure 2A A top view of the brush cleaner 200 shows a cylindrical roller 228 in a processing position, wherein the cylindrical roller 228 is closed or pressed against the main surface of the substrate 201. The brush cleaner 200 also includes one or more drive motors 244 and a rotating device 247. Each of the drive motors 244 and the rotating device 247 includes a roller 249 disposed at the end of the output shaft of each drive motor 244 and the rotating device 247 and configured to support and / or engage the substrate 201 and facilitate rotation of the substrate 201 about an axis parallel to the horizontal plane (i.e., the XY plane).

[0054] Each of the cylindrical rollers 228 includes a tubular cap disposed thereon. Figure 2C and Figure 2D The tubular caps 213a and 213b shown are shown. Figure 2B (Not shown in the image). The tubular caps 213a, 213b may be removable sleeves made of a pad material for polishing substrate 201 or brush bodies suitable for cleaning substrate 201. The tubular caps 213a, 213b are also referred to herein as scrubbing brushes. During processing in the brush cleaner 200, the tubular caps 213a, 213b of the cylindrical roller 228 contact the substrate while they are rotated by actuator 235, and simultaneously the substrate 201 is rotated by using support roller 249, which is coupled to the output shaft of drive motor 244 and rotation device 247. While the substrate 201 and the cylindrical roller 228 are rotated by various actuators and motors, a second processing fluid (such as deionized (DI) water and / or one or more second substrate cleaning fluids (e.g., aqueous solutions containing acid or alkali)) is applied from a second fluid source to the surface of substrate 201.

[0055] According to one embodiment, a dedicated adjustment device 260 may be provided for each of the cylindrical rollers 228. The adjustment device 260 may also be referred to as a "beater bar." The adjustment device 260 is mounted near the sidewall of the groove 205 by one or more support members 270. The adjustment device 260 is positioned away from the center of the groove 205 so as not to interfere with substrate transport and / or substrate polishing or cleaning processes. However, the adjustment device 260 is positioned to contact each of the cylindrical rollers 228 when the first support member 225 and the second support member 230 are actuated downward and outward away from each other. In one embodiment, movement of the first support member 225 and the second support member 230 brings the cylindrical roller 228 into contact with the corresponding adjustment device 260. In this position, the processing surfaces of the tubular caps 213a, 213b on each of the cylindrical rollers 228 can be adjusted during relative movement between the cylindrical roller 228 and the adjustment device 260. In one or more embodiments, a dedicated adjustment device 260 (“stirring bar”) is used during brush cleaning operations to enhance brush cleaning.

[0056] Figure 2C This is an isometric view of one or more embodiments of the scrubbing device 211 disposed within the brush cleaner 200. Figure 2C The scrubbing device 211 shown is depicted with a substrate 201 loaded therein, such that the scrubbing device 211 is in a loaded state. The scrubbing device 211 includes a pair of cylindrical rollers 228, each of which includes a pair of tubular caps 213a, 213b. In one or more embodiments, the pair of tubular caps 213a, 213b are polyvinyl acetate (PVA) brushes. Each brush includes a plurality of raised nodules 215 spanning the surface of the brush, and a plurality of recesses 217 located between the nodules 215. A pair of cylindrical rollers 228 are supported by a pivot mount adapted to move a pair of tubular caps 213a, 213b of the cylindrical rollers 228 to contact and disengage from a substrate 201 (e.g., a semiconductor wafer) supported by a substrate support (which may also be referred to as a wafer support), thereby allowing the cylindrical rollers 228 to move between a closed position and an open position so as to allow the substrate 201 to be withdrawn from and inserted therebetween as described below.

[0057] The scrubbing device 211 also includes a substrate support adapted to support and further adapt to rotate the substrate 201. In one aspect, the substrate support may include a plurality of rollers 249a-c ( Figures 2C to 2DEach of the rollers 249a and 249c has a groove adapted to vertically support the substrate 201. A plurality of first motors of actuator 235 are coupled to the cylindrical roller 228 and adapted to rotate the tubular caps 213a and 213b of the cylindrical roller 228 in a clockwise or counterclockwise rotation direction, respectively. A second motor 244 is coupled to rollers 249a and 249c and adapted to rotate rollers 249a and 249c, respectively, while a third motor 247 is coupled to roller 249b and adapted to rotate roller 249b.

[0058] The scrubbing device 211 may further include a plurality of sprayers 221 (including at least 221a, 221b, 221c, and 221d) coupled to a source 223 of cleaning fluid via a supply pipe 226. The sprayers 221 are configured to spray high-pressure liquid onto the substrate surface to help remove particles, contaminants, and residues. The sprayers 221 may be combined with various configurations, such as fluid nozzles, spray bars with nozzles, shower manifolds, or cryogenic aerosol nozzles.

[0059] In various embodiments of this disclosure, the cleaning fluid used in the brush cleaner may include (but is not limited to) deionized (DI) water, diluted citric acid, diluted quaternary ammonium compounds (mixtures of organic solvents, such as glycol ether, tetramethylammonium hydroxide, and other additives), diluted ammonium hydroxide (NH4OH), diluted hydrogen peroxide (H2O2), a mixture of NH4OH and H2O2 (SC1), a mixture of diluted hydrofluoric acid, sulfuric acid (H2SO4), and hydrogen peroxide (H2O2) (SPM), Electra clean, or any other liquid solution for substrate cleaning.

[0060] In one or more embodiments, the sprayer 221 may be positioned to spray cleaning fluid onto the surface of the substrate 201 or onto one or more scrubbing brushes (e.g., including tubular caps 213a, 213b) during the scrubbing process. In one or more embodiments, the substrate cleaning fluid and / or brush cleaning fluid discussed below may be supplied from an internal region of the scrubbing brushes themselves (e.g., cylindrical roller 228 and tubular caps 213a, 213b). The fluid supplied to the interior of the scrubbing brushes will pass through holes in the tubular caps 213 to clean the surface of the substrate or remove debris found on the surface of the scrubbing brushes.

[0061] Figure 2DThis is an isometric view of one or more embodiments of the scrubbing device 211 of the brush cleaner 200, depicting the scrubbing device 211 in an idle state when no substrate is loaded. In the idle state, the scrubbing device 211 can perform brush cleaning operations. In one or more embodiments, the scrubbing device 211 cannot be used to perform substrate cleaning operations when performing brush cleaning operations. A plurality of sprayers 221 are coupled to a source 223 of brush cleaning fluid via a supply pipe 226. The sprayers 221 can be positioned to spray brush cleaning fluid at one or more scrubbing brushes (e.g., tubular caps 213a, 213b). In one or more embodiments, the brush cleaning fluid can be supplied through the scrubbing brushes themselves.

[0062] In one or more embodiments, the brush cleaning fluid is the same as the substrate cleaning fluid. In one or more embodiments, the brush cleaning fluid is different from the substrate cleaning fluid. For example, the brush cleaning fluid is hydrofluoric acid (e.g., diluted hydrofluoric acid), SPM, or SC1 (e.g., hydrogen peroxide), while the substrate cleaning fluid is a solution different from hydrofluoric acid, SPM, or SC1. In this case, it is desirable to use a brush cleaning fluid configured to effectively clean the surface of the scrubbing brush and remove debris from the surface of the scrubbing brush to improve subsequent substrate cleaning steps. However, these brush cleaning chemicals may corrode and damage one or more materials disposed on the surface of the substrate to be cleaned in the brush cleaner 200. Therefore, these brush cleaning processes need to be performed separately from the substrate cleaning process.

[0063] In one or more embodiments, the sprayer 221 includes a first set of sprayers 221a, 221b for substrate cleaning fluid and a second set of sprayers 221c, 221d for brush cleaning fluid. In these embodiments, the supply pipe 226 is divided into separate supplies (not shown) for sources 223 for substrate cleaning fluid and brush cleaning fluid.

[0064] Overall, the Brush Cleaner 200 ensures effective substrate cleaning in a variety of applications. Its modular design and adjustable support allow the brush holder to accommodate substrates of different sizes and shapes. The actuator, cylindrical rollers, and adjustment mechanism work together to deliver an optimized cleaning process that minimizes the risk of substrate damage while maximizing cleaning efficiency.

[0065] During operation, the substrate handling system transports the substrate 201 to the brush cleaner 200. This system employs precise handling techniques and controlled transport to ensure accurate positioning and orientation of the substrate upon entry into the module. The entire cleaning process is completed within a housing surrounding the substrate, providing a controlled environment for the cleaning process. Within this environment, a cleaning agent delivery system applies a uniform layer of cleaning agent to the surface of the substrate, thereby ensuring effective cleaning across the entire surface.

[0066] As the cleaning agent coats the substrate, a set of brushes gently scrubs the surface to chemically and mechanically remove residues and particles. The brushes work in conjunction with the cleaning agent to optimize cleaning performance while minimizing the risk of substrate damage. Simultaneously, rollers support and rotate the substrate to ensure that the brushes and cleaning agent effectively clean all areas of the surface. Controller 112 manages various components, adjusting parameters such as brush rotation speed, cleaning agent flow rate, and roller rotation speed for maximum efficiency.

[0067] Once scrubbing is complete, rinse the substrate with deionized water or another suitable rinsing agent. This step removes residual cleaning agent and expelled particles from the surface. A drying mechanism (such as an air knife or rotary dryer) is then used to remove any remaining moisture from the substrate, ensuring a clean and dry surface for subsequent processes.

[0068] After the cleaning process is completed, the substrate transport system moves the cleaned substrate to the next process module. This transport maintains the cleanliness of the substrate and ensures proper alignment and orientation for subsequent processes.

[0069] Throughout the operation, controller 112 manages the various components within the brush cleaner. This controller 112 ensures accurate and effective cleaning by adjusting parameters such as brush rotation speed, detergent flow rate, and roller rotation speed. Controller 112 also provides feedback on cleaning performance, enabling the operator to optimize the process to improve substrate cleanliness and process efficiency.

[0070] In addition to the features described above, embodiments of the brush holder may include optional components and accessories to improve its cleaning performance. For example, a temperature control system may be integrated into the brush holder to regulate the temperature of the cleaning fluid, thereby ensuring optimal cleaning conditions for a particular substrate and cleaning agent. The brush holder can also be configured to support multiple cleaning stages using different cleaning fluids, brushes, or other cleaning mechanisms, such as cryogenic aerosols, enabling a more thorough and customized cleaning process tailored to the specific substrate requirements. This flexibility makes the brush holder suitable for a wide range of industries and applications, including semiconductor manufacturing, solar panel production, glass processing, and various other industries requiring precise and efficient substrate cleaning.

[0071] In one or more embodiments, the brush cartridge module is incorporated into an integrated cryogenic aerosol system as a form of cleaning agent delivery system to enhance substrate cleaning performance in hybrid processes. In one embodiment, the integrated cryogenic aerosol system may be a spray bar configured with multiple cryogenic aerosol nozzles. The cryogenic aerosol cleaning system consists of a cryogenic aerosol particle source and nozzles designed to propel cryogenic aerosol particles at high speed toward the substrate. The cryogenic aerosol particles are generated by a cryogenic fluid (such as liquid nitrogen, liquid carbon dioxide, or liquid argon), which is evaporated and rapidly expands to create a jet of particles. The aerosol jet can be adjusted to control the angle, direction, and velocity of the cryogenic aerosol particles, thereby ensuring targeted and effective cleaning.

[0072] The brush cartridge module in this embodiment includes a cryogenic aerosol delivery system configured to generate and guide cryogenic aerosol particles to a substrate surface. The module may also include a brush that can be used in conjunction with the cryogenic aerosol particles to enhance the cleaning process. The brush can be designed to engage with the substrate surface, thereby mechanically removing stubborn residues and particles. The cryogenic aerosol particles act as a cleaning agent by impacting surface contaminants, causing them to freeze, become brittle, and subsequently detach from the substrate surface. This combination of cryogenic aerosol particles and the brush results in a highly efficient and non-destructive cleaning process.

[0073] The controller 112 within the brush holder module coordinates the operation of the brush assembly and the cryogenic aerosol cleaning system, thereby optimizing cleaning efficiency and substrate compatibility. The cryogenic aerosol cleaning system can operate in pulse or continuous mode, depending on specific cleaning requirements and substrate properties.

[0074] This brush cartridge module with integrated cryogenic aerosol nozzles offers several advantages over traditional cleaning methods. The use of cryogenic aerosol particles eliminates the need for liquid chemicals, which can cause watermarks, scratches, corrosion, or surface roughness. Furthermore, the cryogenic aerosol cleaning process provides a versatile and effective cleaning solution for a wide range of contaminants and substrate materials, resulting in cleaner and more passivated surfaces suitable for high-yield, mixed-use applications.

[0075] Figure 3 This is a flowchart illustrating an exemplary process 300 for manufacturing a stacked semiconductor structure according to an embodiment of the present disclosure. Process 300 begins at operation 310, where a wafer 110 comprising multiple dies is initially loaded into an integrated hybrid bonding system equipped with a front-end module 120. System controller 112 is configured to execute a pre-programmed process sequence, which guides an automated modular host 130 to transfer the wafer to different modules for processing.

[0076] At operation 320, optional wet and dry cleaning processes can be used to remove contaminants from the wafer surface. Subsequently, a brush cleaning process is performed (e.g., operation 330). The substrate undergoes a brush cleaning process within a brush cleaning module (e.g., 140A or 140B), which effectively removes particles and contaminants from the substrate surface using a combination of brush rollers, cleaning solution, and high-pressure sprayers.

[0077] Operation 340 represents another optional wet and dry cleaning process similar to Operation 320, which can be performed to further enhance the cleanliness of the wafer surface. Once the cleaning steps are complete, the wafer is moved to the degassing module, where it undergoes a thermal process that evaporates moisture and other adsorbed contaminants from the wafer surface and reduces plastic outgassing of the tape frame during subsequent vacuum processing (e.g., Operation 350).

[0078] At operation 360°, a plasma module is used to activate the wafer surface. The plasma module uses ion bombardment to make the surface hydrophilic, thereby promoting better bonding. Plasma activation ensures that the bonding process produces a high-quality stacked semiconductor structure.

[0079] Operation 370 involves the hydration and drying of the substrate surface. This step ensures optimal bonding conditions by hydrating the surface and then drying it to remove excess moisture.

[0080] In operation 380, a UV release process is performed. A UV module (e.g., 180) is used to expose the adhesive tape frame holding the grains in place to ultraviolet light, thereby altering the molecular structure of the adhesive. This results in a decrease in adhesive strength, allowing the grains to be easily released from the tape frame.

[0081] Finally, at operation 390, the bonding agent 190 ejects, picks up, flips the die, and bonds it to the substrate. The die is bonded to the substrate wafer to form the desired stacked semiconductor structure. Throughout the process, an in-line metrology system can be used to inspect and verify the alignment and positioning of the die and substrate, thereby ensuring a high-quality stacked semiconductor structure.

[0082] This exemplary process for fabricating stacked semiconductor structures using an integrated hybrid bonding platform demonstrates the advantages of a streamlined, automated system that effectively combines various modules and technologies to achieve high-performance die stacking bonding. By incorporating a brush cassette cleaning module into the hybrid bonding platform, this disclosure provides an effective and efficient method for removing residues and particles from die surfaces in die stacking bonding applications, thereby improving bonding yield. The brush cassette cleaning module offers advantages over conventional wet cleaning methods because it removes stubborn residues and particles that are firmly adhered to the substrate surface without causing watermarks, scratches, corrosion, or surface roughness.

[0083] In alternative embodiments, the hybrid platform and brush cassette assembly can be adapted to different substrate sizes, shapes, and materials. For example, the brush cassette assembly can be configured to clean substrates made of silicon, glass, or quartz materials. Similarly, the brush cassette assembly can be adapted to clean substrates of various sizes, such as 200mm, 300mm, or 450mm wafers.

[0084] In some embodiments, the brush box cleaning module may include multiple brush box assemblies configured in parallel or series to enhance cleaning efficiency and effectiveness. For example, the brush box cleaning module may include a first brush box assembly configured to remove coarse particles and residues, followed by a second brush box assembly configured to remove fine particles and residues.

[0085] In other embodiments, the brush box cleaning module can be configured to use different types of brushes or cleaning agents, depending on the specific cleaning requirements and substrate material. For example, brushes can be made of various materials such as polyvinyl alcohol / acetate (PVA), nylon, polypropylene, or other suitable materials, with different porous structures or bristle-containing structures, having the desired rigidity and structural configuration. Cleaning agents may include deionized (DI) water, diluted citric acid, diluted quaternary ammonium compounds (mixtures of organic solvents such as glycol ethers, tetramethylammonium hydroxide, and other additives), diluted ammonium hydroxide (NH4OH), diluted hydrogen peroxide (H2O2), a mixture of NH4OH and H2O2 (SC1), a diluted mixture of hydrofluoric acid, sulfuric acid (H2SO4), and hydrogen peroxide (H2O2) (SPM), Electra Clean, or other chemicals suitable for effectively removing residues and particles.

[0086] In addition to die stacking applications, hybrid bonding platforms and brush cassette assemblies can also be used in other semiconductor manufacturing processes that require cleaning of substrate surfaces, such as wafer bonding, 3D integration, or advanced packaging processes.

[0087] It should be noted that this disclosure is not limited to the specific embodiments and applications described herein, and modifications, variations, and alternative embodiments may be made without departing from the spirit and scope of this disclosure as defined by the appended claims.

Claims

1. A hybrid platform, the hybrid platform comprising: A substrate handling system configured to transport a substrate across the platform; A brush box cleaning module, which is coupled to the platform and configured to clean the surface of the substrate by removing residues and particles; A bonding module, coupled to the platform and configured to bond dies to the surface of the substrate; as well as A controller configured to control the substrate handling system, the brush box cleaning module, and the bonding module.

2. The hybrid platform of claim 1, wherein the substrate handling system is further configured to transport the substrate between different process modules.

3. The hybrid platform of claim 1, wherein the brush box cleaning module is configured to remove residues and particles caused by back abrasion tape or swivel tape.

4. The hybrid platform of claim 1, wherein the brush box cleaning module comprises a plurality of brushes configured to remove stubborn residues and particles from the substrate surface in a chemical and mechanical manner.

5. The hybrid bonding platform of claim 1, wherein the bonding module is configured to perform a hybrid bonding process on the cleaned surface of the substrate.

6. The hybrid integration platform as claimed in claim 1, wherein the hybrid integration platform further comprises: A system controller, which manages and controls the operation of each process module.

7. A brush cassette assembly for cleaning a substrate in a hybrid bonding platform, the brush cassette assembly comprising: A housing configured to surround the substrate; Multiple brushes, the multiple brushes being configured to gently scrub the wafer surface; Multiple rollers configured to support and rotate the wafer during the cleaning process; as well as A cleaning agent delivery system configured to apply a cleaning agent to the wafer surface during the scrubbing process.

8. The brush cartridge assembly of claim 6, further comprising: A controller configured to control the operation of the brush, the roller, and the cleaning agent delivery system.

9. The brush cartridge assembly of claim 6, wherein the plurality of brushes are configured to remove, chemically and mechanically, stubborn residues and particles caused by backing tape or dicing tape from the substrate surface.

10. The brush cartridge assembly of claim 6, wherein the cleaning agent delivery system is configured to deliver the cleaning agent to the plurality of brushes to facilitate the removal of residues and particles from the substrate surface.

11. The brush cartridge assembly of claim 6, wherein the cleaning agent delivery system includes a cryogenic aerosol nozzle configured to dispense cryogenic cleaning agent onto the substrate surface during the scrubbing process.

12. A process for manufacturing a stacked semiconductor structure, the process comprising: Provides a substrate comprising multiple grains; The surface of the substrate is cleaned using a brush box cleaning module to remove residues and particles; as well as The grains of the substrate are bonded using a hybrid bonding process.

13. The process of claim 11, wherein cleaning the surface of the substrate includes removing residues and particles caused by back-abrasion tape or dicing tape.

14. The process of claim 11, wherein cleaning the surface of the substrate comprises using a plurality of brushes to remove stubborn residues and particles chemically and mechanically.

15. The process of claim 11, wherein the cleaning step using at least one wet cleaning module is optional and may be performed before and / or after the brush box cleaning module step.

16. The process of claim 11, wherein the at least one degassing module heats the wafer surface to evaporate moisture and reduce degassing from the plastic of the tape frame.

17. The process of claim 11, wherein the at least one plasma module uses ion bombardment to activate the wafer surface, thereby making it hydrophilic for bonding.

18. The process of claim 11, wherein the at least one bonding module accurately aligns and bonds the die to the substrate to produce a stacked semiconductor structure.

19. The process of claim 11, wherein the stacked semiconductor structure has enhanced bonding yield due to the removal of residues and particles by the brush cleaning module.

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