Plasma activation-bonding device and method with frequency conversion function

Abstract

The invention relates to the field of semiconductor preparation and bonding processes, and provides plasma activation-bonding equipment with a frequency conversion function, which mainly comprises a vacuum cavity, a radio frequency power supply system, two guide rails arranged oppositely, an electrode and wafer fixing component and an air inlet / air outlet. And the radio frequency power supply system controls the two electrodes to be respectively connected with a high-frequency power supply and a low-frequency power supply, carries out power supply frequency change, carries out plasma activation on a plurality of wafers fixed on the wafer fixing component, and realizes in-situ bonding of the wafers in the vacuum cavity through the guide rail. According to the invention, the wafer fixing part used by the bonding cavity and the electrode used by the plasma activation cavity are integrated, so that the total volume of the device is reduced. And secondly, the electrodes are transiently switched between the high frequency and the low frequency, so that a plurality of wafers can be activated in a single-step process, and the wafer activating and bonding efficiency is improved. The problems of pollution, inactivation, process drift and the like caused by wafer transfer in the ectopic bonding process are avoided, and the process requirement that wafer activation and bonding can be completed without transfer in the in-situ bonding process is met.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of semiconductor manufacturing and bonding process, in particular, the present application relates to a plasma activated-bonding device and method with frequency conversion function. BACKGROUND

[0002] Plasma activated bonding (PAB) is the mainstream method for wafer low-temperature bonding process, which uses plasma (common process gas is Ar, O2, N2, etc.) to activate (irradiate) the wafer surface, which can not only clean the surface impurities, but also introduce active groups to increase the bonding strength between wafers. However, the traditional process adopts ex-situ bonding, and the plasma activation cavity and the bonding cavity are separated. After plasma activation, the wafer needs to be transferred from the activation cavity to the bonding cavity, which is exposed to air during the transfer process, which can easily lead to rapid deactivation of the wafer surface hydroxyl / amino and reduce the bonding strength.

[0003] In-situ bonding is an advanced process that continuously completes wafer surface activation and bonding in the same vacuum environment or sealed cavity, which avoids the pollution and surface deactivation problems caused by wafer transfer after activation in traditional process, and is especially suitable for heterogeneous material integration and high-precision devices. The traditional plasma activation cavity adopts one upper electrode (gas shower head) and one lower electrode (wafer carrier), which are connected to high-frequency and low-frequency power sources respectively, so as to form an electric field region between the upper electrode and the lower electrode and generate uniform plasma, thereby bombarding the wafer surface to remove the contaminants and oxide layer on the wafer surface and achieve wafer surface activation. However, this method can only activate a single wafer at the same time, and the activation efficiency is low, and it is difficult to meet the requirements of in-situ bonding. SUMMARY

[0004] Starting from the prior art, the task of the present application is to provide a plasma activated-bonding device and method with frequency conversion function. Through the bonding device and method, the problems of pollution, deactivation and process drift caused by wafer transfer during ex-situ bonding can be effectively solved, and the efficiency of wafer activation and bonding can be improved.

[0005] The present application provides a plasma activated-bonding device and method with frequency conversion function, which comprises:

[0006] a vacuum cavity configured to perform plasma activation and bonding process;

[0007] a wafer fixing component, which at least includes a first wafer fixing component and a second wafer fixing component arranged oppositely inside the vacuum cavity;

[0008] An electrode, which at least includes a first electrode and a second electrode oppositely arranged inside the vacuum cavity, and the first wafer fixing component is integrated with the first electrode, and the second wafer fixing component is integrated with the second electrode; and

[0009] A radio frequency power supply system configured to be connected with the first electrode and the second electrode, the radio frequency power supply system has at least two outputs, and can transiently switch between different frequencies, so that the first electrode and the second electrode always maintain an opposite configuration of one connected to a high frequency power supply and the other connected to a low frequency power supply.

[0010] Further, the implementation of the radio frequency power supply system includes:

[0011] An intelligent power supply with power distribution and management functions, the intelligent power supply is configured to directly control the output parameters of each output terminal; and / or

[0012] Independent high frequency power supply, low frequency power supply and control device, the frequency of the high frequency power supply is greater than 5 times the frequency of the low frequency power supply, the control device is configured to control the circuit connection mode, so that the radio frequency power supply system switches between the following two modes, and the switching time is less than 50ms:

[0013] The first mode is configured to connect the high frequency power supply with the first electrode, and the low frequency power supply with the second electrode; and

[0014] The second mode is configured to connect the high frequency power supply with the second electrode, and the low frequency power supply with the first electrode.

[0015] Further, the vacuum cavity includes:

[0016] The first end is arranged with the first wafer fixing component and the first electrode;

[0017] The second end is arranged opposite to the first end, and is arranged with the second wafer fixing component and the second electrode;

[0018] The third end is arranged on the side surface between the first end and the second end, and is perpendicular to the first end and the second end or forms a preset included angle with the first end and the second end, and is arranged with an air inlet, the air inlet is configured to have a plurality of independent air inlet channels and is uniformly distributed along the circumference of the cavity side surface; and

[0019] The fourth end is arranged opposite to the third end, and is arranged with an air outlet, the relative positions of the air inlet and the air outlet are configured to make the process gas flow through the area between the first electrode and the second electrode.

[0020] Further, the device further comprises a first guide rail and a second guide rail configured to control the movement of the first wafer fixing component and the second wafer fixing component respectively, the first guide rail is integrated with the first wafer fixing component and the first electrode, and the second guide rail is integrated with the second wafer fixing component and the second electrode.

[0021] Further, the ultimate vacuum degree of the vacuum cavity is less than or equal to 1 Pa.

[0022] Further, the wafer fixing component comprises an electrostatic chuck.

[0023] The application further provides a plasma activation-bonding method based on the device, comprising the following steps:

[0024] Step S1, fixing a first wafer to be bonded on a first wafer fixing component, and fixing a second wafer to be bonded on a second wafer fixing component;

[0025] Step S2, vacuumizing the vacuum cavity, introducing process gas through the gas inlet, and controlling the radio frequency power supply system to perform the following steps:

[0026] Step S21, connecting the high frequency power supply with the first electrode, connecting the low frequency power supply with the second electrode, and performing plasma activation on the second wafer; and

[0027] Step S22, connecting the low frequency power supply with the first electrode, connecting the high frequency power supply with the second electrode, and performing plasma activation on the first wafer;

[0028] The step S21 and the step S22 are arranged to be performed alternately to perform plasma activation on the first wafer and the second wafer; and

[0029] Step S3, after the plasma activation is completed, performing bonding of the first wafer and the second wafer in the vacuum cavity.

[0030] Further, the process gas comprises at least one of Ar, O2 and / or N2.

[0031] Further, the plasma activation process adjusts the process gas flow and the power supply power in real time through a monitoring system to maintain the stability of the plasma activity, and the monitoring system comprises a sensor for monitoring the plasma emission spectrum.

[0032] Further, the bonding process is performed in the vacuum state of the vacuum cavity, and the vacuum destruction rate is less than 10 -3 Pa / h.

[0033] The application provides a plasma activation-bonding device and method with a frequency conversion function, which has at least the following advantages: first, the electrostatic chuck (used for fixing and adsorbing a wafer) used in the bonding cavity is combined with the electrode (used for generating plasma) used in the plasma activation cavity, and the transfer cavity structure is omitted, so that the area occupied by the device is reduced by 30% compared with the traditional separate device. Second, by instantaneously switching the electrode between high frequency and low frequency, a plurality of wafers can be activated in a single step process, and the activation intensity difference between the wafers is less than 5%, thereby improving the efficiency of wafer activation and bonding. The gas inlet is provided as a plurality of independent gas inlets, and different process gases can enter the vacuum cavity respectively. The gas outlet is arranged opposite to the gas inlet, so as to ensure that the process gas uniformly flows through the electrode area and avoid secondary pollution.

[0034] Meanwhile, the application also has the following unexpected technical effects: by completing the wafer activation and bonding process in the same vacuum cavity, the lifetime of the wafer surface hydroxyl group can be prolonged by more than 10 times. Through the device and method, the problems of pollution, inactivation and process drift caused by transferring wafers in the ex situ bonding process are avoided, and the process requirements of in situ bonding, i.e., wafer activation and bonding can be completed without transferring, are met. BRIEF DESCRIPTION OF DRAWINGS

[0035] To further clarify the advantages and features of the embodiments of the present application, a more particular description of the embodiments of the present application will be rendered by reference to specific embodiments thereof which are illustrated in the drawings. It is to be understood that these drawings are only schematic and are non-limiting embodiments of the application, and that the application is not limited to the specific embodiments depicted in the drawings. In the drawings, like components are labelled with the same or similar references. Wherever possible, the same or like component has been given the same or a similar reference numeral, and a detailed description of the same has not been repeated.

[0036] Figure 1 Fig. 1 shows the main structure of a plasma activation-bonding device with a frequency conversion function according to an embodiment of the present application.

[0037] Figure 2 Fig. 2 shows a power frequency conversion scheme of a radio frequency power supply system of the plasma activation-bonding device with a frequency conversion function according to an embodiment of the present application.

[0038] Figure 3 Fig. 3 shows a frequency F-time T variation diagram of the first electrode and the second electrode in the plasma activation process according to an embodiment of the present application.

[0039] Figure 4 Fig. 4 shows a process flow diagram of a plasma activation-bonding method according to an embodiment of the present application.

[0040] LIST OF REFERENCE NUMERALS

[0041] 100 plasma activation-bonding device

[0042] 01 Radio frequency power supply system

[0043] 02 Vacuum chamber

[0044] 03 First guide rail

[0045] 04 Second guide rail

[0046] 05 First electrode

[0047] 06 Second electrode

[0048] 07 First wafer fixing member

[0049] 08 Second wafer fixing member

[0050] 09 Inlet

[0051] 10 Outlet

[0052] 11 First wafer

[0053] 12 Second wafer

[0054] P1 Intelligent power supply

[0055] P2 High frequency power supply

[0056] P3 Low frequency power supply

[0057] O1 First output end

[0058] O2 Second output end

[0059] C Control device DETAILED DESCRIPTION

[0060] It should be noted that the components in the various figures can be shown exaggeratedly for illustration purposes and are not necessarily to scale. In the various figures, the same or functionally similar components are provided with the same reference numerals.

[0061] In the present invention, unless specifically indicated, "arranged on", "arranged above" and "arranged over" do not exclude the presence of an intermediate between the two. In addition, "arranged on or above" only indicates the relative position between the two components, and in certain cases, such as after reversing the product direction, it can also be converted to "arranged below or below", and vice versa.

[0062] In the present invention, each embodiment is only intended to illustrate the scheme of the present invention and should not be understood as limiting.

[0063] In the present invention, unless specifically indicated, the quantifier "one" does not exclude the scenario of multiple elements.

[0064] It should also be noted that, in the embodiments of the present invention, only a portion of the components or parts may be shown for clarity and simplicity. However, those skilled in the art will understand that, under the teachings of the present invention, necessary components or parts can be added as needed for specific scenarios. Furthermore, unless otherwise stated, features in different embodiments of the present invention can be combined with each other.

[0065] It should also be noted that, within the scope of this invention, the terms "same," "equal," and "equal to" do not imply that the two values ​​are absolutely equal, but rather allow for a certain reasonable margin of error. In other words, the terms also encompass "substantially the same," "substantially equal," and "substantially equal to." Similarly, in this invention, the directional terms "perpendicular to," "parallel to," etc., also encompass the meanings of "substantially perpendicular to" and "substantially parallel to."

[0066] Furthermore, the numbering of the steps in the methods of the present invention does not limit the execution order of the method steps. Unless otherwise specified, the method steps may be executed in different orders.

[0067] The present invention will be further described below with reference to the accompanying drawings and specific embodiments.

[0068] Figure 1 The diagram shows the main structure of a plasma activation-bonding device with frequency switching function in one embodiment of the present invention.

[0069] like Figure 1 As shown, the device 100 mainly includes a radio frequency power supply system 01 with frequency conversion function, a vacuum chamber 02, a first guide rail 03 and a second guide rail 04, a first electrode 05 and a second electrode 06, a first wafer fixing component 07 and a second wafer fixing component 08, an air inlet 09, and an air outlet 10. The first guide rail 03, the first electrode 05, and the first wafer fixing component 07 are integrated and disposed at the upper end of the vacuum chamber 02; conversely, the second guide rail 04, the second electrode 06, and the second wafer fixing component 08 are integrated and disposed at the lower end of the vacuum chamber 02, and their electrical isolation structure is optimized.

[0070] The guide rail and the wafer fixing component are connected through a slider-rail sliding connection, and the manufacturing precision of the slider and the rail is ±0.01 mm. The electrode and the wafer fixing component are integrally formed (such as ceramic co-firing), reducing the number of connectors. The integrated structure of the guide rail, the electrode and the wafer fixing component is modularly designed, connected through a positioning pin and a quick plug-in interface, and convenient to disassemble and replace. The guide rail is driven by a servo motor matched with a ball screw, the motor is installed outside the vacuum cavity, and the internal screw is connected through a magnetic coupler or a bellows sealed transmission shaft. When the guide rail is driven, the electrode and the wafer fixing component move synchronously, and through the servo motor-ball screw system and the laser displacement sensor closed loop control, the distance between the electrode and the wafer surface is kept constant, and the precision is ±0.05 mm.

[0071] Specifically, the electrical isolation structure optimization includes:

[0072] An intermediate isolation layer is made of high-strength ceramic or other insulating materials, the thickness of the insulating material is 5-10 mm, and the insulation resistance is >10 14 Ω;

[0073] A ring-shaped insulating gasket is designed, the gap is filled with insulating glue, and a groove type shielding structure is arranged to absorb stray electromagnetic fields, so as to realize electrical shielding of the structure gap;

[0074] The driving system of the guide rail adopts magnetic coupling transmission, and the transmission components are sprayed with insulating coating to block current conduction.

[0075] The electrode connecting line is made of a coaxial shielded cable, and a ceramic sealing feedthrough is arranged at the lead-out position to constrain high-frequency current.

[0076] Through the above design, the insulation effect of adjacent conductive components in the integrated structure can be optimized, the cross talk of high-frequency / low-frequency signals between the electrode, the guide rail and the cavity can be effectively avoided, the stability of the electric field parameters during plasma activation can be ensured, and the long-term operation reliability of the equipment in a high vacuum and strong electromagnetic field environment can be met.

[0077] Preferably, the gas inlet 09 is provided as a plurality of gas inlet channels and is evenly distributed circumferentially along the side of the cavity. The gas inlet channel aperture gradually changes, and the gas inlet channel aperture gradually changes. The angle between the cavity tangent is a certain angle, and the radial gas distribution uniformity difference is <2%. The gas inlet channel supports the introduction of different gases, and each gas inlet channel is provided with a high-precision mass flow controller to accurately control the gas parameters. The gas inlet 09 is independent of the first electrode 05 and the second electrode 06, does not occupy the top / bottom space, the adsorption, radio frequency and cooling channels of the electrode can be kept intact, and no additional holes are needed.

[0078] The functions of each component in the device 100 will be described in detail below.

[0079] RF power supply system 01, configured to directly control the double output frequency by intelligent power supply or control device matched by high frequency and low frequency power supply, realize fast switching of upper and lower electrode frequency within 50ms, and then symmetrically activate the wafer.

[0080] Vacuum cavity 02, configured to provide a high vacuum environment to isolate pollution and ensure that the wafer is not disturbed by the atmosphere during activation and bonding, and to integrate plasma activation and bonding process, optimize equipment floor space, and realize uniformity of airflow in the cavity through reasonable gas inlet and outlet design.

[0081] First guide rail 03 and second guide rail 04, configured to precisely control the lifting of wafer fixing components and complete the switching from the activation station to the bonding station.

[0082] First electrode 05 and second electrode 06, configured as RF power supply load, and used to activate the wafer by different frequency combinations.

[0083] First wafer fixing component 07 and second wafer fixing component 08, configured to fix and carry the wafer.

[0084] Gas inlet 09 and gas outlet 10, configured to introduce process gas in real time according to process requirements, make the airflow path pass between the first electrode 05 and the second electrode 06, provide working medium for plasma activation, maintain stable cavity pressure through multi-point gas inlet and lateral exhaust, and timely discharge etching by-products to avoid secondary pollution.

[0085] When the device is working, process gas is introduced into the vacuum cavity 02 through the gas inlet 09 and discharged through the gas outlet 10. The RF power supply system 01 controls the first electrode 05 and the second electrode 06 to alternately activate the first wafer 11 and the second wafer 12 by power frequency switching.

[0086] Figure 2 A power frequency switching scheme of an RF power supply system of a plasma activation-bonding device with frequency switching function in an embodiment of the present application is shown. As shown in Figure 2 , the implementation of the RF power supply system includes:

[0087] ①As shown in Figure 2 a, an intelligent power supply P1 with power distribution and management function is used to directly control the output parameters of the first output end O1 and the second output end O2;

[0088] ②As shown in Figure 2 b and Figure 2As shown in Figure c, two independent high-frequency power supplies P2 and P3 are used. Through the control device C, the outputs of P2 and P3 can be switched between a first output terminal O1 and a second output terminal O2. This allows switching between state 1 (high frequency output at first output terminal O1, low frequency output at second output terminal O2) and state 2 (low frequency output at first output terminal O1, high frequency output at second output terminal O2). Preferably, the control device C is a switching device with high switching frequency characteristics, capable of rapidly switching between high-frequency and low-frequency outputs in less than 50ms.

[0089] In schemes ① and ② above, the first output terminal O1 is connected to the first electrode 05, and the second output terminal O2 is connected to the second electrode 06. The first electrode 05 and the second electrode 06 are always connected to a high-frequency power supply and a low-frequency power supply, respectively. The frequency of the high-frequency power supply is greater than five times the frequency of the low-frequency power supply. This frequency separation allows for independent control of plasma parameters: the high frequency controls the plasma density, and the low frequency controls the plasma bombardment energy, ultimately achieving an optimal balance on the wafer surface in terms of activation level, damage control, and active group density. By switching the frequencies of the first electrode 05 and the second electrode 06 during the activation process, both the first wafer 11 and the second wafer 12 can be activated in a single process step, achieving similar activation effects. This avoids problems such as contamination, deactivation, and process drift caused by the separation of activation and bonding processes in traditional processes, thereby achieving a high-strength, low-defect bonding effect.

[0090] Figure 3 The image shows the frequency F-time T variation of the first and second electrodes during plasma activation in one embodiment of the present invention. Figure 3 As shown, during the plasma activation process, the first electrode 05 and the second electrode 06 always maintain one high-frequency output F1 and the other low-frequency output F2 at the same time. At specific time points (T1, T2, T3, ...), the frequencies of the first electrode 05 and the second electrode 06 are alternately switched between high-frequency F1 and low-frequency F2 by the control of the intelligent power supply P1 or the control device C.

[0091] Figure 4 A process flow diagram of a plasma activation-bonding method according to one embodiment of the present invention is shown. Figure 4 As shown, the method includes the following steps:

[0092] Step S1: Fix the first wafer 11 to be bonded on the first wafer fixing component 07, and fix the second wafer 12 to be bonded on the second wafer fixing component 08.

[0093] Step S2, vacuumize the vacuum chamber 02, introduce process gas through the gas inlet 09, control the radio frequency power supply system 01, alternately perform the following steps until the total plasma activation time reaches the set value:

[0094] Step S21, the high frequency power supply is connected to the first electrode 05, the low frequency power supply is connected to the second electrode 06, and the second wafer 12 is plasma activated; and

[0095] Step S22, the low frequency power supply is connected to the first electrode 05, the high frequency power supply is connected to the second electrode 06, and the first wafer 11 is plasma activated.

[0096] Step S3, after the plasma activation is completed, the bonding of the first wafer 11 and the second wafer 12 is performed in the vacuum chamber 02, and the first wafer 11 and the second wafer 12 do not need to be transferred during the plasma activation and the bonding process.

[0097] The following takes the bonding of silicon-quartz glass as an example to illustrate the plasma activation-bonding method:

[0098] In an embodiment of the present application, the first wafer 11 is a silicon wafer, and the second wafer 12 is a quartz glass wafer; the first wafer fixing member 07 and the second wafer fixing member 08 are electrostatic chuck.

[0099] The first wafer 11 and the second wafer 12 to be bonded are subjected to RCA standard cleaning (RCA Standard Clean) to remove surface organic matter, metal ions and particle contamination, and the wafer surface contact angle after cleaning is <5°.

[0100] The silicon wafer and the quartz glass wafer are transferred to the electrostatic chuck for adsorption by a mechanical arm, the electrostatic chuck applies a 1kV direct current voltage, and the adsorption force uniformity difference is <3%. The door of the vacuum chamber 02 is closed, the pumping system is started, the vacuum degree of the vacuum chamber 02 is reduced to 0.1Pa, then process gas (gas composition O2:Ar=3:1, total flow rate 100sccm) is introduced through the gas inlet 09, and the pressure in the vacuum chamber is stabilized to 5-15Pa. By controlling the output of the radio frequency power supply system 01, the radio frequency power supply system is switched between the following two modes, and the switching time is less than 50ms:

[0101] The first mode is to connect the first electrode 05 to a high-frequency power supply of 400 kHz (power 75 W) and the second electrode 06 to a low-frequency power supply of 40 kHz (power 20 W) for 50 ms-10 s. At this time, the high-frequency power supply generates high-density plasma near the first electrode 05 to provide sufficient oxygen radicals; the low-frequency power supply generates high-energy ion bombardment at the second electrode 06 (quartz glass side) to break the Si-O bond on the SiO2 surface and introduce hydroxyl groups.

[0102] The second mode is to connect the first electrode 05 to the low-frequency power supply and the second electrode 06 to the high-frequency power supply for the same time as the first mode. The low-frequency power supply generates ion bombardment at the first electrode 05 (silicon wafer side) to remove the natural oxide layer on the silicon surface and expose silicon atoms; the high-frequency power supply maintains the plasma density at the second electrode 06 to ensure a continuous supply of oxygen radicals.

[0103] The radio frequency power supply system 01 repeats switching between the first mode and the second mode until the total activation time (10-60 s) is reached, and the time for switching modes is always less than 50 ms. During the plasma activation process, the characteristic emission spectrum of oxygen atoms is monitored in real time, and the gas flow is adjusted in feedback to maintain the plasma active particle concentration within a suitable range.

[0104] After activation, the second wafer fixing component 08 is lifted by the second guide rail 04 to make the first wafer 11 contact and bond with the second wafer 12, and then annealed at 200-300°C for 2-6 h to complete the bonding.

[0105] After the bonding is completed, infrared imaging detection is used to detect the bonding interface of the first wafer 11 and the second wafer 12, and the results show that the bonding strength of the bonding interface is high and the void rate is less than 0.1%, meeting the packaging requirements of high-performance devices.

[0106] In the above, the composition and flow of the process gas are only used as an example of plasma activation of silicon wafers-quartz wafers, and for different wafer materials, the composition, ratio and flow parameters of the gas can be adjusted to obtain the best activation effect.

[0107] Although the above describes various embodiments of the present application, it should be understood that they are presented only as examples and not as limitations. It is obvious to those skilled in the relevant art that various combinations, modifications and changes can be made without departing from the spirit and scope of the present application. Therefore, the breadth and scope of the present application disclosed herein should not be limited by the above disclosed exemplary embodiments, but should only be defined according to the appended claims and their equivalent replacements.

Claims

1. A plasma activation-bonding device with frequency switching function, characterized in that, The device includes: A vacuum chamber configured for plasma activation and bonding processes; A wafer fixing component, comprising at least a first wafer fixing component and a second wafer fixing component disposed opposite to each other inside the vacuum cavity; An electrode, comprising at least a first electrode and a second electrode disposed opposite to each other within the vacuum cavity, wherein the first wafer fixing component is integrated with the first electrode, and the second wafer fixing component is integrated with the second electrode; and A radio frequency power supply system is configured to be connected to the first electrode and the second electrode. The radio frequency power supply system has at least two outputs and can transiently switch between different frequencies, so that the first electrode and the second electrode always maintain an opposite configuration, with one connected to a high-frequency power supply and the other connected to a low-frequency power supply.

2. The device according to claim 1, characterized in that, The radio frequency power supply system includes: An intelligent power supply with power distribution and management functions, configured to directly control the output parameters of each output terminal; and / or The system includes an independent high-frequency power supply, a low-frequency power supply, and a control device. The frequency of the high-frequency power supply is greater than five times the frequency of the low-frequency power supply, and the control device is configured to control the circuit connection, enabling the RF power system to switch between two modes with a switching time of less than 50ms: A first mode is configured such that the high-frequency power supply is connected to the first electrode, and the low-frequency power supply is connected to the second electrode; and In the second mode, the high-frequency power supply is connected to the second electrode, and the low-frequency power supply is connected to the first electrode.

3. The device according to claim 1, characterized in that, The vacuum cavity includes: The first end is provided with the first wafer fixing component and the first electrode; The second end is configured to be opposite to the first end, and is provided with the second wafer fixing component and the second electrode; The third end is configured as a side surface connecting the first end and the second end, and is perpendicular to or at a predetermined angle to both the first end and the second end, and is provided with an air inlet. The air inlet is constructed to have multiple independent air intake channels, evenly distributed circumferentially along the side surface of the cavity; and The fourth end is positioned opposite the third end and has an outlet. The relative positions of the inlet and outlet are configured to allow process gas to flow through the region between the first electrode and the second electrode.

4. The device according to claim 3, characterized in that, It also includes a first guide rail and a second guide rail, which are configured to control the movement of the first wafer fixing component and the second wafer fixing component, respectively. The first guide rail is integrated with the first wafer fixing component and the first electrode, and the second guide rail is integrated with the second wafer fixing component and the second electrode.

5. The device according to claim 4, characterized in that, The ultimate vacuum level of the vacuum chamber is less than or equal to 1 Pa.

6. The device according to claim 1, characterized in that, The wafer fixing component includes an electrostatic chuck.

7. A plasma activation-bonding method based on the device described in claim 1, characterized in that, Includes the following steps: Step S1: Fix the first wafer to be bonded on the first wafer fixing component, and fix the second wafer to be bonded on the second wafer fixing component; Step S2: Evacuate the vacuum chamber, introduce process gas through the air inlet, and control the radio frequency power system to perform the following steps: Step S21: The high-frequency power supply is connected to the first electrode, and the low-frequency power supply is connected to the second electrode to perform plasma activation on the second wafer; as well as Step S22: The low-frequency power supply is connected to the first electrode, and the high-frequency power supply is connected to the second electrode to perform plasma activation on the first wafer; Steps S21 and S22 are configured to be performed alternately to perform plasma activation on the first wafer and the second wafer; as well as Step S3: After the plasma activation is completed, the first wafer and the second wafer are bonded in the vacuum chamber.

8. The method according to claim 7, characterized in that, The process gas includes at least one of the following: Ar, O2 and / or N2.

9. The method according to claim 7, characterized in that, The plasma activation process uses a monitoring system to adjust the process gas flow rate and power supply in real time to maintain stable plasma activity. The monitoring system includes sensors that monitor the plasma emission spectrum.

10. The method according to claim 7, characterized in that, The bonding process is performed while the vacuum chamber is kept under vacuum, and the vacuum breaking rate is less than 10. -3 Pa / h.

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