METHOD AND APPARATUS FOR RPS-RF PLASMA CLEANING AND ACTIVATION FOR advanced SEMICONDUCTOR PACKAGES

Abstract

Embodiments of the present disclosure provided herein include systems and methods for plasma cleaning and activation using hybrid bonding. The system includes: a processing chamber; a substrate support configured to support a substrate during a hybrid bonding substrate process; a gas delivery system coupled to the processing chamber, the gas delivery system having at least one radical generator; and a controller configured to cause the substrate processing system to: form a first layer on a first substrate; dissociating the gas in the at least one radical generator to form a plasma; flowing the plasma into a processing space of the processing chamber for a period of time; discharging the plasma, by-products, and exhaust gas from the processing space after the period of time; and adhering a second layer disposed on a second substrate to the first layer using a hybrid bonding technique.

Description

Technical Field

[0001] The embodiments of this disclosure generally relate to semiconductor manufacturing. More specifically, this disclosure relates to plasma cleaning and activation for advanced semiconductor packaging. Background Technology

[0002] Copper-dielectric hybrid bonding is a popular technology in the semiconductor manufacturing industry due to its ability to integrate two-dimensional materials into semiconductor production lines. Copper-dielectric hybrid bonding achieves three-dimensional integration by forming a three-dimensional stack through back-end-of-line (BEOL) layers using face-to-face two-dimensional wafer or die bonding. This technology involves the direct bonding of patterned metal / dielectric surfaces, with copper being one of the metals used for bonding. Copper is a preferred material for bonding due to its excellent electrical, thermal, and mechanical properties. Hybrid bonding is used to establish a reliable connection between the upper and lower pads, and the expansion of copper during the bonding process is crucial for eliminating radial-shaped hollows that can affect the bonding process.

[0003] However, copper dielectric hybrid bonding faces some challenges, including removing particles and organic residues from the deposition process on the surface of the metal and dielectric layers while maintaining control over morphology and defect rate.

[0004] In addition to these challenges, copper pads may contain particles or organic residues from chemical mechanical polishing (CMP), which can create voids. Voids can be caused by the gas-phase release of surface contaminants and residues. Additionally, voids can be caused by physical particles or particles that directly interfere with interlayer bonding.

[0005] Therefore, improved hybrid bonding techniques are needed in semiconductor manufacturing to reduce defect rates and further control morphology. Summary of the Invention

[0006] The embodiments described herein generally relate to systems and methods for semiconductor manufacturing. More specifically, the embodiments herein provide processes and methods for plasma cleaning and activation in advanced semiconductor packaging using hybrid bonding to allow for improved bonding characteristics.

[0007] In one embodiment, a substrate processing system is provided. The system includes: a processing chamber surrounding a processing space; a substrate support disposed within the processing space, configured to support the substrate during hybrid bonding substrate processing; a gas delivery system fluidly coupled to the processing chamber, having at least one free radical generator; an exhaust device fluidly coupled to the processing space; and a controller configured to cause the substrate processing system to: form a first layer on a first substrate; dissociate gas in the at least one free radical generator to form plasma; allow the plasma to flow into the processing space of the processing chamber for a period of time; after the period of time, discharge the plasma, byproducts, and waste gas from the processing space; and adhere a second layer disposed on a second substrate to the first layer using a hybrid bonding technique.

[0008] In another embodiment, a substrate processing system is provided. The system includes: a processing chamber surrounding a processing space; a substrate support disposed within the processing space, configured to support a substrate during hybrid bonding substrate processing; a radio frequency generator coupled to the substrate support; a gas delivery system fluidly coupled to the processing chamber, having at least one free radical generator; an exhaust device fluidly coupled to the processing space; and a controller configured to cause the substrate processing system to: form a first layer on a first substrate; dissociate a gas in the at least one free radical generator to form a plasma; allow the plasma to flow into the processing space for a first period of time; after the first period of time, discharge the plasma, byproducts, and waste gas from the processing space; allow a second gas to flow into the processing space; bias the substrate support using the radio frequency generator to generate a second plasma for a second period of time; after a second cleaning period, discharge the second plasma, byproducts, and waste gas from the processing space; and adhere a second layer disposed on a second substrate to the first layer using a hybrid bonding technique.

[0009] In yet another embodiment, a substrate processing system is provided. The system includes: a processing chamber surrounding a processing space; a substrate support disposed within the processing space, configured to support the substrate during hybrid bonding substrate processing; a first radio frequency (RF) generator coupled to the substrate support; a second RF generator coupled to an upper electrode; a gas delivery system fluidly coupled to the processing chamber; an exhaust device fluidly coupled to the processing space; and a controller configured to cause the substrate processing system to: form a first layer on a first substrate; allow gas to flow into the processing space; bias the substrate support using the first and second RF generators to generate plasma for a period of time; after the period of time, discharge plasma, byproducts, and waste gas from the processing space; and adhere a second layer disposed on a second substrate to the first layer using hybrid bonding technology. Attached Figure Description

[0010] To gain a more detailed understanding of the features described above, a more specific description of the present disclosure can be provided by referring to embodiments, some of which are illustrated in the accompanying drawings. However, it should be noted that the drawings illustrate only exemplary embodiments of the disclosure and should not be construed as limiting its scope, as the disclosure may allow for other equivalent embodiments.

[0011] Figure 1 A schematic cross-sectional side view of a processing system according to certain embodiments is shown.

[0012] Figure 2 A schematic cross-sectional side view of a processing system according to certain embodiments is shown.

[0013] Figure 3 The illustration depicts a method for cleaning a chamber or substrate used for mixing and bonding, according to certain embodiments.

[0014] Figure 4 The illustration depicts the experience according to certain implementation methods. Figure 3 A schematic cross-sectional view of the substrate used in the method.

[0015] Figure 5 The illustration depicts a method for cleaning a chamber or substrate used for mixing and bonding, according to certain embodiments.

[0016] Figure 6 The illustration depicts the experience according to certain implementation methods. Figure 5 A schematic cross-sectional view of the substrate used in the method.

[0017] Figure 7 The illustration depicts a method for cleaning a chamber or substrate used for mixing and bonding, according to certain embodiments.

[0018] Figure 8 The illustration depicts the experience according to certain implementation methods. Figure 7 A schematic cross-sectional view of the substrate used in the method.

[0019] For ease of understanding, the same reference numerals have been used where possible to indicate common elements in the figures. Elements and features of one embodiment are contemplated to be advantageously incorporated into other embodiments without further description. Detailed Implementation

[0020] This disclosure generally relates to semiconductor manufacturing. More specifically, this disclosure relates to plasma cleaning and activation for hybrid bonding in advanced semiconductor packaging.

[0021] The substrate preparation process is crucial for establishing strong bonds when using copper-dielectric hybrid bonding (CDHB). Typically, the substrate is thoroughly cleaned using solvents such as acetone or isopropanol, and plasma treatment may also be used to remove any residual contaminants or activate the bonded surfaces. This preparation ensures clean or activated surfaces for subsequent steps.

[0022] In the next stage, a dielectric layer is deposited onto each substrate to isolate the copper layers disposed on the substrate and prevent electrical short circuits. This deposition is performed using methods such as chemical vapor deposition (CVD) or sputtering. The dielectric layer acts as an insulating barrier between the copper layers, thereby ensuring proper functioning.

[0023] A key step in the CDHB process is substrate bonding. Here, the substrates are aligned and fused together via fusion bonding. The copper-silicon hybrid bonding mechanism for the silicon-based dielectric interlayer involves initial low-temperature van der Waals hydrogen bonding, followed by annealing to form stronger covalent bonds between the activated dielectric layer surfaces. Copper pad bonding is achieved through a copper diffusion bonding mechanism, where the copper surface is recessed by CMP dishing to allow the dielectric surfaces to contact and bond first. Subsequently, an additional annealing step allows the copper pads to thermally expand, connecting the two copper surfaces through thermal diffusion and plastic deformation for a stable bond.

[0024] However, CDHB presents significant challenges to advanced semiconductor packaging. Successful implementation requires a defect-free, high-yield, and high-volume integrated solution, as well as advanced semiconductor packaging equipment. The chip-to-wafer (C2W) bonding large-scale integration system is equipped with key modules for wet cleaning, degassing, plasma activation, and precision bonding steps.

[0025] However, to meet the critical requirements of high-volume manufacturing (HVM) in advanced semiconductor packaging, such as high bonding yield and sustained mean time between failures (MTBF) or mean wafers between cleans (MWBC) gain, as well as reduced cost of ownership (CoO), more stringent control over HB tooling is required. This includes controlling particle or organic defects, the stability of bonding surface cleaning or activation processes, and ensuring a long lifespan for the chamber hardware.

[0026] This disclosure provides a system and method for configuring a remote plasma source and an RF plasma chamber for hybrid bonding, as well as for substrate cleaning. The disclosure provides a processing chamber in a processing system comprising at least one remote plasma source (RPS) disposed on one of the top of the chamber, one of the sidewalls of the chamber, or a combination thereof. The processing chamber is also configured for RF capacitively coupled plasma (CCP) cleaning, comprising a first RF generator and a second RF generator. The first RF generator is coupled to a substrate support disposed within the processing chamber, and the second RF generator is coupled to the top of the processing chamber, for example, to a chamber cover assembly or to a nozzle. The substrate prepared for hybrid bonding can be exposed to RPS cleaning processes, RF CCP cleaning processes, or combinations thereof.

[0027] Therefore, this disclosure provides improved methods and apparatus for RPS-RF radical and plasma cleaning and activation, enabling production-value-added HB chamber hardware and bonding surface processes. This disclosure offers tunability and flexibility, long-term reliability, and reduced costs, and can be effectively integrated into various semiconductor HVM equipment tools.

[0028] Figure 1 A processing system 100 is illustrated for performing a copper-dielectric hybrid bonding substrate processing method. The processing system 100 includes a processing chamber 102, a gas delivery system 104 fluidly coupled to the processing chamber 102, and a system controller 108. The processing chamber 102 includes a chamber cover assembly 110, one or more sidewalls 112, and a chamber bottom 114, which together define a processing space 121. The processing space 121 is fluidly coupled to an exhaust device 117, such as one or more vacuum pumps, for maintaining the processing space 121 at sub-atmospheric pressure and for exhausting processing gases and processing byproducts from the processing space 121.

[0029] The chamber cover assembly 110 includes a cover plate 116 and a nozzle 118 coupled to the cover plate 116 to define a gas distribution space 119. The nozzle 118 faces a substrate support assembly 120 disposed in a processing space 121. The substrate support assembly 120 is configured to move a substrate support member 122 between an elevated substrate processing position (as shown) and a lowered substrate transport position (not shown).

[0030] A gas delivery system 104 is fluidly coupled to a processing chamber 102 via at least one gas inlet 123, which is provided through a cover plate 116, one or more sidewalls 112, or both (both shown in the figure). Processing or cleaning gas delivered by the gas delivery system 104 flows through at least one gas inlet 123 and a baffle 124 in the cover plate 116 into a gas distribution space 119, and is distributed into the processing space 121 through multiple openings 132 in the nozzle 118. The chamber cover assembly 110 further includes a perforated diffuser plate 125 disposed between at least one gas inlet 123 in the cover plate 116 and the nozzle 118. Gas flowing into the gas distribution space 119 is first diffused by the diffuser plate 125 to provide a more uniform or desired airflow distribution into the processing space 121. Cleaning gas can also be delivered and enter the processing space 121 through gas inlets 123 in one or more sidewalls 112. Processing gases and processing byproducts are discharged from the processing space 121 through openings in one or more sidewalls 112.

[0031] A purge gas source 137, in fluid communication with the processing space 121, allows chemically inert purge gases (e.g., argon (Ar) and helium (He)) to flow into a region located below the substrate support 122, for example, through an opening in the chamber bottom 114 surrounding a movable support shaft 162 that supports the substrate support 122. The purge gas can be used to create a positive pressure area below the substrate support 122 relative to the pressure in the processing space 121 during substrate processing. Typically, the purge gas introduced through the chamber bottom 114 flows upward and around the edge of the substrate support 122, to be discharged from the processing space 121 through openings in one or more sidewalls 112.

[0032] The substrate support assembly 120 includes a movable support shaft 162 that can be surrounded by a bellows 165. The substrate support assembly 120 includes a lifting rod assembly 166, which includes a plurality of lifting rods 167 coupled to a lifting rod clamp 168. The plurality of lifting rods 167 are movably disposed in an opening formed through the substrate support member 122. When the substrate support member 122 is in a lowered substrate transport position (not shown), the plurality of lifting rods 167 extend beyond the substrate receiving surface of the substrate support member 122 to lift the substrate 130 and provide access to the back surface of the substrate 130. When the substrate support member 122 is in a raised or processed position, the plurality of lifting rods 167 retract below the substrate receiving surface of the substrate support member 122 to allow the substrate 130 to rest on the substrate support member 122. Multiple lifting rods 167 can lift the substrate 130 during processing (e.g., during a remote plasma source cleaning process or an RF capacitive coupling cleaning process) so that cleaning gas and cleaning plasma can flow on opposite sides of the substrate 130 (e.g., the front and back sides of the substrate 130).

[0033] As shown, the processing system 100 can be configured to form capacitively coupled plasma (CCP), including an upper electrode (e.g., cover plate 116) disposed adjacent to the processing space 121, and facing a lower electrode (e.g., substrate support assembly 120) disposed in the processing space 121 opposite to the upper electrode. A first plasma generator assembly 154A includes a first RF generator 150A and a first RF generator assembly 151A, and is electrically coupled to the upper electrode to deliver an RF signal configured to ignite and sustain the plasma. The first RF generator 150A includes a first RF matching circuit 153A and a first filter assembly 152A disposed within the first RF generator assembly 151A. The lower electrode (e.g., substrate support assembly 120) is coupled to a second plasma generator assembly 154B. Figure 1 As shown, one or more components of the substrate support assembly 120, such as the substrate electrode 126 embedded in the substrate support assembly 120, are electrically coupled to the second plasma generator assembly 154B. The second RF generator 150B includes a second RF matching circuit 153B and a second filter assembly 152B disposed within the second RF generator assembly 151B.

[0034] Alternatively, nozzle 118 may be electrically coupled to a first RF generator 150A to ignite and sustain plasma of the process gas flowing into the process space 121 via capacitive coupling thereto. In some embodiments, process chamber 102 includes an inductive plasma generator (not shown) and forms plasma by inductively coupling RF power to the process gas.

[0035] A second plasma generator assembly 154B, including a second RF generator 150B and a second RF generator assembly 151B, is typically configured to deliver a desired amount of continuous wave (CW) or pulsed RF power to the substrate electrode 126 of the substrate support assembly 120 at a desired substantially fixed sinusoidal frequency based on a control signal provided from the system controller 108. During processing, the second plasma generator assembly 154B is configured to deliver RF power (e.g., an RF signal) to the substrate electrode 126 disposed adjacent to the substrate support 122 and within the substrate support assembly 120. The RF power delivered to the substrate electrode 126 is configured to ignite and sustain the processing plasma using the processing gas disposed in the processing space 121 and the field generated by the RF power (RF signal) delivered to the substrate electrode 126 by the second RF generator 150B.

[0036] The gas delivery system 104 may include one or more remote plasma sources (e.g., a first radical generator 106A and a second radical generator 106B), a deposition gas source 140, and a conduit system 194 that fluidly couples the first radical generator 106A, the second radical generator 106B, and the deposition gas source 140 to the processing space 121. The first radical generator 106A may be disposed at the top of the processing chamber 102, and the second radical generator 106B may be disposed on a side wall of the processing chamber 102. Alternatively, the second radical generator 106B may be disposed at the top of the processing chamber 102, and the first radical generator 106A may be disposed on a side wall of the processing chamber 102. The first radical generator 106A and the second radical generator 106B are fluidly coupled to the processing space 121 through a gas inlet 123. Each gas inlet 123 includes a baffle 124 at its distal end to generate a laminar flow of gas or plasma entering the processing space 121 from the first radical generator 106A and the second radical generator 106B. The gas delivery system 104 further includes a plurality of isolation valves 190 disposed between the first radical generator 106A and the cover plate 116 and between the second radical generator 106B and the gas inlet 123, respectively. The isolation valves 190 can be used to fluidly isolate each of the first radical generator 106A and the second radical generator 106B from the processing chamber 102.

[0037] although Figure 1 The previous description depicted two remote plasma sources, but this disclosure covers the use of only one remote plasma source, such as a first radical generator 106A. In this single RPS configuration, the first radical generator 106A may be located on top of the processing chamber 102 or on either side wall 112 of the processing chamber 102.

[0038] A first radical generator 106A includes a first plasma chamber space 181A, and a second radical generator 106B includes a second plasma chamber space 181B. The first radical generator 106A is coupled to a first power source 193A, and the second radical generator 106B is coupled to a second power source 193B. The first power source 193A is used to ignite and maintain a plasma of gas supplied from a first gas source 187A to the first plasma chamber space 181A. The second power source 193B is used to ignite and maintain a plasma of gas supplied from the second gas source 187B to the second plasma chamber space 181B. Either the first radical generator 106A or the second radical generator 106B can be used to generate clean radicals used in a chamber cleaning process by igniting and maintaining a clean plasma from a clean gas mixture supplied by the first gas source 187A or the second gas source 187B, respectively. Clean gas mixtures may contain H2, N2, Ar, He, NH3, NF3, clean dry air (CDA), or combinations thereof.

[0039] Suitable remote plasma sources that can be used in one or both of the first radical generator 106A and the second radical generator 106B include radio frequency (RF) or very high radio frequency (VHRF) capacitively coupled plasma (CCP) sources, inductively coupled plasma (ICP) sources, microwave-induced (MW) plasma sources, electron cyclotron resonance (ECR) plasma sources, helical plasma sources, or other high-density plasma (HDP) sources.

[0040] The operation of the processing system 100 is facilitated by a system controller 108. The system controller 108 includes a programmable central processing unit (CPU) 195, which operates in conjunction with memory 196 (e.g., non-volatile memory) and support circuitry 197. The CPU 195 is one of any type of general-purpose computer processor used in an industrial environment, such as a programmable logic controller (PLC), for controlling various chamber components and subprocessors. The memory 196, coupled to the CPU 195, facilitates the operation of the processing chamber. The support circuitry 197 is conventionally coupled to the CPU 195 and includes caches, frequency circuitry, input / output subsystems, power supplies, and combinations thereof, coupled to various components of the processing system 100, to facilitate control related to board processing operations.

[0041] The instructions in memory 196 are in the form of a program product, such as a program that implements the methods of this disclosure. In one example, this disclosure can be implemented as a program product stored on a computer-readable storage medium for use with a computer system. The program definition of the program product contains the functionality of the embodiments of the methods described herein. Therefore, a computer-readable storage medium is an embodiment of this disclosure when it carries computer-readable instructions that direct the functionality of the methods described herein.

[0042] Figure 2 A schematic cross-sectional side view of the processing chamber 200 is shown. The processing chamber 200 is illustrated as an alternative processing chamber configured for back-side processing. The back-side processing chamber 200 is a plasma-enhanced chemical vapor deposition chamber. In some embodiments, Figure 2 The back-side processing chamber 200 shown can also be used for plasma etching processes. In other embodiments, the back-side processing chamber 200 can be used for either deposition or etching, requiring a separate chamber for each process.

[0043] A back-side processing chamber 200 is configured to receive a substrate 205 and clean or activate the back-side surface 220 of the substrate 205. The substrate 205 is conveyed into the back-side processing chamber 200 via a transfer port 225 and then to a platform 230. The platform 230 is adapted to receive and hold the substrate 205 in a downward orientation (i.e., front surface 215 facing upward and back surface 220 facing downward). The platform 230 is coupled to a rod 235, which is movable at least in the vertical (up and down) direction to change the spacing between the substrate 205 and the perforated panel 240. The platform 230 includes a holder 245 suspending the substrate 205 from its edge. The platform 230 includes a heater 250 to control the temperature of the substrate 205.

[0044] The back-side processing chamber 200 is configured to deposit a film onto the back-side surface 220, or to etch a film previously formed on the back-side surface 220. The back-side processing chamber 200 is coupled to a power source 255 for forming a plasma within the chamber. The power source 255 is configured to form the plasma by applying radio frequency (RF) power, extremely high radio frequency (VHF) power in capacitively coupled plasma applications, inductively coupled power (ICP) applications, microwave power applications, reactive ion etching (RIE) power applications, or electron cyclotron resonance (ECR) power applications. The back-side processing chamber 200 is also coupled to a gas source 260.

[0045] In the deposition process, gas source 260 contains precursor gases for forming dielectric, semiconductor, or metal films as a back-side coating using plasma. Optionally, a specific film pattern can be formed on the back-side surface 220 of substrate 205 using mask 265 during the deposition process. In the etching process, gas source 260 contains various gases for generating plasma to remove the dielectric, semiconductor, or metal films previously formed on the back-side surface 220 of substrate 205.

[0046] The back-side processing chamber 200 is also coupled to a remote plasma chamber 270. The remote plasma chamber 270 is coupled to a clean gas source 275. Clean gas from the clean gas source 275 is provided to the remote plasma chamber 270, wherein the clean gas is energized and provided as plasma to the back-side processing chamber 200, which is used to clean the internal components of the back-side processing chamber 200.

[0047] Processing chamber 200 is also configured for cleaning using capacitively coupled plasma. Power source 255 may be adapted to deliver RF energy to processing region 221 of processing chamber 200 through one or more portions of processing chamber 200. During operation of processing chamber 200, power source 255 is used to bias portions of processing chamber 200 (e.g., the bottom of processing chamber 200) to form plasma in processing region 221.

[0048] During processing, rod 235 may be connected to an RF generator (not shown) to apply RF bias power to a portion of holder 245 to draw ions present in the plasma to the surface of substrate 205. In one embodiment, holder 245 is grounded, DC biased, or electrically floated during the plasma process to minimize ion bombardment damage to substrate 205.

[0049] Figure 3 A method 300 for cleaning remote plasma sources for hybrid bonding in advanced packaging of substrates is illustrated. Method 300 can be used with... Figure 1 Processing system 100 or Figure 2 The processing system 200 is used together to clean the substrate 130 and the processing space 121 for hybrid bonding. Figure 4 The substrate undergoing method 300 is illustrated, and references are made in the description of method 300. Figure 4 .

[0050] Method 300 begins in block 302 by forming a first layer 402 on a first substrate (e.g., substrate 130). The first layer 402 may include multiple layers and may contain various materials. Specifically, the first layer 402 may include at least one dielectric portion 404 and at least one metal portion 406. The dielectric portion 404 may include any suitable dielectric, such as silicon dioxide or silicon nitride. The metal portion 406 may contain any conductive metal, such as copper, aluminum, tungsten, or titanium. After the formation of the first layer 402, residues or particles 408 may remain on the surface of the first layer 402. These residues or particles 408 may interfere with hybrid bonding and hinder proper adhesion between layers.

[0051] To remove residues or particles 408 and prepare the surface of the first layer 402 for bonding, the surface of the first layer 402 is cleaned and / or activated. In block 304, a cleaning or activating gas is dissociated, and reactive radicals are generated in a remote plasma source (e.g., a first radical generator 106A) to clean and / or activate the first layer 402. The cleaning or activating gas may contain... Figure 1 Any clean gas mixture discussed. See reference. Figure 1 The cleaning or activating gas is ignited to form a cleaning / activating plasma 182A within the first plasma chamber space 181A. Subsequently, in block 306, during the cleaning / activation period, the cleaning / activating plasma 182A is allowed to flow into the processing space 121 of the processing chamber 102. The cleaning period can be any suitable length, for example, from 10 seconds to about 30 minutes, for example, from about 30 seconds to about 5 minutes, for example, about 1 minute. The first layer 402 is exposed to the cleaning / activating plasma 182A, causing residues or particles 408 on the surface of the first layer 402 to react and evaporate to generate exhaust gas.

[0052] In block 308, upon completion of the cleaning / activation process (e.g., after the cleaning / activation period), the cleaning / activation plasma 182A, products, and waste gases are discharged from the processing space 121. Method 300 may return to block 304 for another iteration of the RPS cleaning / activation process, and if necessary, for the same number of iterations. Subsequently, in block 310, the first layer 402 of the first substrate may be co-bonded with a complementary layer 412 disposed on the complementary substrate 410. The complementary layer 412 may include at least one complementary dielectric portion 414 and at least one complementary metal portion 416. Prior to the co-bonding operation in block 310, the complementary layer 412 may have been cleaned and / or activated using a remote plasma source as described in blocks 304 through 308.

[0053] Figure 5 A method 500 is illustrated for a combined cleaning / activation process using a remote plasma source (RPS) and radio frequency (RF) capacitively coupled plasma (CCP) for hybrid bonding in advanced packaging of substrates. Method 500 can be used with... Figure 1 Processing system 100 or Figure 2 The processing system 200 is used together to clean and / or activate the substrate 130 and the processing space 121 for hybrid bonding. Figure 6 The substrate undergoing method 500 is illustrated, and references are made in the description of method 500. Figure 6 .

[0054] Method 500 begins in block 502 by forming a first layer 602 on a first substrate (e.g., substrate 130). The first layer 602 may include multiple layers and may contain various materials. Specifically, the first layer 602 may include at least one dielectric portion 604 and at least one metal portion 606. The dielectric portion 604 may include any suitable dielectric, such as silicon dioxide or silicon nitride. The metal portion 606 may contain any conductive metal, such as copper, aluminum, tungsten, or titanium. After the formation of the first layer 602, residues or particles 608 may remain on the surface of the first layer 602. These residues or particles 608 may interfere with hybrid bonding and hinder proper adhesion between layers.

[0055] To remove residues or particles 608 and prepare the surface of the first layer 602 for bonding, the surface of the first layer 602 is cleaned and / or activated. In block 504, a first cleaning or activating gas is dissociated, and reactive radicals are generated in a remote plasma source (e.g., a first radical generator 106A). The first cleaning or activating gas may be... Figure 1 Any clean gas mixture discussed. See reference. Figure 1The first cleaning or activating gas is ignited to form a first cleaning / activating plasma 182A within the first plasma chamber space 181A. Subsequently, in frame 506, the first cleaning / activating plasma 182A is allowed to flow into the processing space 121 of the processing chamber 102 for a first cleaning period. The first cleaning period can be of any suitable length, for example, from 10 seconds to about 30 minutes, from about 30 seconds to about 5 minutes, or from about 1 minute. The first layer 602 is exposed to the cleaning / activating plasma 182A, causing residues or particles 608 on the surface of the first layer 602 to react and evaporate to generate exhaust gas.

[0056] In box 508, upon completion of the cleaning / activation process, the cleaning / activation plasma 182A, byproducts, and waste gas can be discharged from the processing space 121. Method 500 can return to box 504 for another iteration of the RPS cleaning / activation process, and, if necessary, for the same number of iterations as required.

[0057] Subsequently, within frame 510, a second cleaning or activating gas can be introduced into the processing space 121 of the processing chamber 102. The second cleaning or activating gas may include the same composition as the first cleaning or activating gas, or may include a different composition configured to react with any remaining residues or particles 608 or to activate the bonded surfaces.

[0058] In frame 512, the first layer 602 undergoes a radio frequency (RF) capacitively coupled plasma (CCP) cleaning process, wherein the substrate support assembly 120 is biased using at least one of a first RF generator 150A and a second RF generator 150B. A second cleaning or activating gas is ignited and dissociated within the processing chamber 102 to form a second cleaning / activating plasma 610, wherein ions from the second cleaning / activating plasma 610 bombard residual residues or particles 608 on the surface of the first layer 602, thereby generating a second waste gas. The second cleaning / activating plasma 610 is present in the processing space 121 for a second cleaning period. The second cleaning period can be of any suitable length, for example, from 10 seconds to about 30 minutes, for example, from about 30 seconds to about 5 minutes, for example, about 1 minute, and can be shorter or longer than the first cleaning period.

[0059] In block 514, the second cleaning / activation plasma 610, byproducts, and second waste gas can be discharged from the processing space 121. Method 500 can return to block 510 for another iteration of the RF CCP cleaning / activation process, and if necessary, for the same number of iterations. Subsequently, in block 516, the first layer 602 can be co-bonded with a complementary layer 622 disposed on a complementary substrate 620. The complementary layer 622 may include at least one complementary dielectric portion 624 and at least one complementary metal portion 626. The complementary layer 622 may also be cleaned and / or activated using a remote plasma source and a CCP source as described in blocks 504 through 514.

[0060] Alternatively, the RPS cleaning / activation process (e.g., boxes 504-508) and the RF CCP cleaning / activation process (e.g., boxes 510-514) can be interchanged, such that the RF CCP cleaning / activation process precedes the RPS cleaning / activation process. Furthermore, the RPS cleaning / activation process and the RF CCP cleaning / activation process can be repeated as many times as desired in any desired order. For example, the cleaning / activation process may include a first round of RPS cleaning / activation, followed by a first round of RF CCP cleaning / activation, and then a second round of RPS cleaning / activation. Another example cleaning / activation process may include a first round of RF CCP cleaning / activation, followed by a second round of RF CCP cleaning / activation, and then a first round of RPS cleaning / activation.

[0061] Figure 7 A method 700 for cleaning or activating a remote plasma source for hybrid bonding in advanced packaging of substrates is illustrated. Method 700 can be used with... Figure 1 The processing system 100 is used together to clean and / or activate the substrate 130 and the processing space 121 for hybrid bonding. Figure 8 The substrate undergoing method 700 is illustrated, and references are made in the description of method 700. Figure 8 .

[0062] Method 700 begins in block 702 by forming a first layer 802 on a first substrate (e.g., substrate 130). The first layer 802 may comprise multiple layers and may contain various materials. Specifically, the first layer 802 may include at least one dielectric portion 804 and at least one metal portion 806. The dielectric portion 804 may comprise any suitable dielectric, such as silicon dioxide or silicon nitride. The metal portion 806 may comprise any conductive metal, such as copper, aluminum, tungsten, or titanium. After the formation of the first layer 802, residues or particles 808 may remain on the surface of the first layer 802. These residues or particles 808 may interfere with hybrid bonding and hinder proper adhesion between the layers.

[0063] To remove residues or particles 808 and prepare the surface of the first layer 802 for bonding, the surface of the first layer 802 is cleaned and / or activated. In frame 704, a cleaning or activating gas is introduced into the processing space 121 of the processing chamber 102. The cleaning or activating gas may contain approximately [missing information - likely related to specific gases or components]. Figure 1 Any combination of clean gases discussed. Subsequently, in block 706, when the substrate support assembly 120 and cover plate 116 are biased using the first RF generator 150A and the second RF generator 150B, the clean or activating gas is ignited and dissociated in the processing space 121 to form a clean / activating plasma 810. The first layer 802 is exposed to the clean / activating plasma 810, causing residues or particles 808 on the surface of the first layer 802 to react and evaporate to generate exhaust gas.

[0064] In block 708, upon completion of the cleaning / activation process, the cleaning / activation plasma 810, byproducts, and waste gas are discharged from the processing space 121. Method 700 may return to block 704 for another iteration of the RF CCP cleaning / activation process, and, if necessary, for the same number of iterations. Subsequently, in block 710, the first layer 802 may be co-bonded with a complementary layer 822 disposed on a complementary substrate 820. The complementary layer 822 may include at least one complementary dielectric portion 824 and at least one complementary metal portion 826. The complementary layer 822 may also be cleaned or activated using a CCP cleaning process as described in blocks 704 through 708.

[0065] This disclosure provides the flexibility to configure radical and plasma RPS / RF cleaning or activation to meet various cleaning or surface preparation or activation requirements, such as combined or separate RPS or RF plasma processes. For example, RPS, RF plasma, RF-assisted RPS, RPS-assisted RF plasma, or intermittent RPS and RF processes can be selected and performed to remove various residues or particles remaining on the surface of chamber components or wafers / dies, and to achieve non-destructive activation or cleaning of hybrid bonded surfaces.

[0066] When describing elements of this disclosure or exemplary aspects thereof or one or more embodiments, the articles “a,” “an,” “the,” and “the” are intended to mean that there are one or more elements.

[0067] The terms “include,” “contain,” and “have” are used to indicate that there may be other elements besides those listed.

[0068] The term "coupling" as used in this article refers to direct or indirect coupling between two objects. For example, if object A contacts object B and object B contacts object C, then object A and object C can still be considered coupled to each other—even if object A and object C do not have direct physical contact with each other. For example, even if the first object never has direct physical contact with the second object, the first object can still be coupled to the second object.

[0069] Although the foregoing description is an implementation method of this disclosure, other and further implementation methods of this disclosure may be designed without departing from the basic scope of this disclosure, and the scope of this disclosure is defined by the following claims.

Claims

1. A substrate processing system, the substrate processing system comprising: A processing chamber that surrounds a processing space; A substrate support is disposed within the processing space and configured to support the substrate during the hybrid bonding substrate processing. A gas delivery system fluidly coupled to the processing chamber, the gas delivery system including at least one free radical generator; An exhaust device, which is fluidly coupled to the processing space; as well as A controller configured to cause the substrate processing system to: (a) A first layer is formed on a first substrate; (b) Dissociating the gas in the at least one free radical generator to form a plasma; (c) The plasma is allowed to flow into the processing space of the processing chamber for a period of time; (d) After the stated time period, the plasma, byproducts, and waste gas are discharged from the processing space; and (e) Using hybrid bonding technology, the second layer disposed on the second substrate is adhered to the first layer.

2. The substrate processing system of claim 1, wherein the first layer comprises a dielectric portion and a metal portion, the dielectric portion comprising silicon dioxide and the metal portion comprising copper.

3. The substrate processing system of claim 1, wherein the gas comprises H2, N2, Ar, He, NH3, NF3, clean dry air (CDA), or a combination thereof.

4. The substrate processing system of claim 1, wherein the at least one free radical generator comprises a first free radical generator disposed on the top of the processing chamber or a second free radical generator disposed on the side wall of the processing chamber.

5. The substrate processing system of claim 1, wherein the processing chamber is configured for front-side and back-side processing.

6. The substrate processing system of claim 5, wherein the substrate support includes a lifting rod configured to support the substrate such that the plasma flows on opposite sides of the substrate.

7. The substrate processing system of claim 1, wherein the controller is further configured to cause the substrate processing system to iteratively repeat (b), (c) and (d) prior to performing (e).

8. A substrate processing system, the substrate processing system comprising: A processing chamber that surrounds a processing space; A substrate support is disposed within the processing space and configured to support the substrate during the hybrid bonding substrate processing. A radio frequency generator, the radio frequency generator being coupled to the substrate support; A gas delivery system fluidly coupled to the processing chamber, the gas delivery system including at least one free radical generator; An exhaust device, which is fluidly coupled to the processing space; as well as A controller configured to cause the substrate processing system to: (a) A first layer is formed on a first substrate; (b) Dissociating the first gas in the at least one free radical generator to form a plasma; (c) Allow the plasma to flow into the processing space for a first period of time; (d) After the first time period, the plasma, byproducts and waste gas are discharged from the processing space; (e) Allow the second gas to flow into the processing space; (f) Using the radio frequency generator to bias the substrate support to generate a second plasma for a second period of time; (g) After the second cleaning time, the second plasma, byproducts, and waste gas are discharged from the processing space; and (h) Using hybrid bonding technology, the second layer disposed on the second substrate is adhered to the first layer.

9. The substrate processing system of claim 8, wherein the first layer comprises a dielectric portion and a metal portion, the dielectric portion comprising silicon dioxide and the metal portion comprising copper.

10. The substrate processing system of claim 8, wherein the first gas comprises H2, N2, Ar, He, NH3, NF3, clean dry air (CDA), or a combination thereof.

11. The substrate processing system of claim 8, wherein the at least one free radical generator comprises a first free radical generator disposed on the top of the processing chamber or a second free radical generator disposed on the side wall of the processing chamber.

12. The substrate processing system of claim 8, wherein the processing chamber is configured for front-side and back-side processing.

13. The substrate processing system of claim 8, wherein the second gas comprises H2, N2, Ar, He, NH3, NF3, clean dry air (CDA) or a combination thereof, and has a different composition from the first gas.

14. The substrate processing system of claim 8, wherein the controller is further configured to iteratively repeat at least one of (b), (c) and (d) or (e), (f) and (g) prior to execution (h).

15. A substrate processing system, the substrate processing system comprising: A processing chamber that surrounds a processing space; A substrate support is disposed within the processing space and configured to support the substrate during the hybrid bonding substrate processing. A first radio frequency generator is coupled to the substrate support. A second radio frequency generator is coupled to the upper electrode; A gas delivery system, which is fluidly coupled to the processing chamber; An exhaust device, which is fluidly coupled to the processing space; as well as A controller configured to cause the substrate processing system to: (a) A first layer is formed on a first substrate; (b) Allow gas to flow into the processing space; (c) The substrate support is biased using the first radio frequency generator and the second radio frequency generator to generate plasma for a period of time. (d) After the stated time period, the plasma, byproducts, and waste gas are discharged from the processing space; and (e) Using hybrid bonding technology, the second layer disposed on the second substrate is adhered to the first layer.

16. The substrate processing system of claim 15, wherein the first layer comprises a dielectric portion and a metal portion, the dielectric portion comprising silicon dioxide and the metal portion comprising copper.

17. The substrate processing system of claim 15, wherein the gas comprises H2, N2, Ar, He, NH3, NF3, clean dry air (CDA), or a combination thereof.

18. The substrate processing system of claim 15, wherein the upper electrode is a chamber cover or a nozzle disposed within the processing chamber.

19. The substrate processing system of claim 15, wherein the processing chamber is configured for front-side and back-side processing.

20. The substrate processing system of claim 15, wherein the controller is further configured to iteratively repeat (b), (c) and (d) prior to execution (e).

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