Wafer bonding method

Abstract

The present application relates to the field of semiconductor technology, and specifically to a wafer bonding method, comprising: placing an activated carbon sheet in a bonding chamber; irradiating the activated carbon sheet with an activation gun to introduce active functional groups on the surface of the activated carbon sheet and change the pore structure of the activated carbon sheet; after the activated carbon sheet is left to stand for a preset time, taking the activated carbon sheet out of the bonding chamber; bonding a first wafer to a second wafer in the bonding chamber to obtain a bonded wafer. The embodiments of the present application can greatly improve the cleanliness of the bonding chamber and effectively improve the wafer bonding yield.

Description

Technical Field

[0001] The present application relates to the field of semiconductor technology, and in particular to a wafer bonding method. Background Art

[0002] Wafer bonding is a key technology in the semiconductor manufacturing process, which involves precisely bonding two or more wafers together. Tiny particles are prone to exist in vacuum chambers with poor cleanliness. These particles will be sandwiched between the two wafers during the bonding process, resulting in poor contact in local areas, thus forming voids or defects, affecting the bond strength, and may cause failures in subsequent process steps. In addition to the above problems, wafer bonding chambers with poor cleanliness can also lead to problems including chemical contamination, improper humidity control, electrostatic adsorption, and bonding interface defects. These problems work together to significantly reduce the quality and consistency of bonding, ultimately leading to a significant reduction in bonding yield. Summary of the invention

[0003] The purpose of the present application is to provide a wafer bonding method, which can significantly improve the cleanliness of the bonding chamber and effectively increase the wafer bonding yield.

[0004] The embodiment of the present application is implemented as follows:

[0005] The present application provides a wafer bonding method, including:

[0006] placing an activated carbon sheet in a bonding chamber;

[0007] Using an activation gun to irradiate the activated carbon sheet, so as to introduce active functional groups into the surface of the activated carbon sheet and change the pore structure of the activated carbon sheet;

[0008] After the activated carbon sheet is left to stand for a preset time, the activated carbon sheet is taken out from the bonding chamber;

[0009] The first wafer and the second wafer are bonded in a bonding chamber to obtain a bonded wafer.

[0010] As an optional implementation, placing the activated carbon sheet in the bonding chamber includes:

[0011] A first activated carbon sheet is arranged on the surface of the unloading platform of the bonding chamber; and a second activated carbon sheet is laid on the upper electrostatic chuck of the bonding chamber.

[0012] As an optional implementation manner, bonding the first wafer and the second wafer in a bonding chamber to obtain a bonded wafer includes:

[0013] Using a first activation gun and a second activation gun to irradiate the first wafer and the second wafer respectively, so that activation layers are formed on the surfaces of the first wafer and the second wafer;

[0014] The activation layer on the first wafer is laminated with the activation layer on the second wafer, and the first wafer and the second wafer are pressure-bonded.

[0015] As an optional implementation manner, before using the first activation gun and the second activation gun to irradiate the first wafer and the second wafer respectively, the method further includes:

[0016] Disposing a third activated carbon sheet between the first wafer and the second wafer;

[0017] An activation gun is used to emit plasma toward the third activated carbon sheet.

[0018] As an optional implementation manner, after the activated carbon sheet is allowed to stand for a preset time, removing the activated carbon sheet from the bonding chamber comprises:

[0019] removing the second activated carbon sheet from the bonding chamber;

[0020] Bonding a first wafer and a second wafer in a bonding chamber to obtain a bonded wafer includes:

[0021] placing a second wafer on an upper electrostatic chuck of the bonding chamber;

[0022] An activation gun is used to irradiate the second wafer and an activation layer is formed on the surface of the second wafer, and the first activated carbon sheet absorbs particulate matter generated by the second wafer.

[0023] As an optional embodiment, after the second wafer is irradiated with an activation gun and an activation layer is formed on the surface of the second wafer, and the first activated carbon sheet adsorbs particulate matter generated by the second wafer, the activated carbon sheet is allowed to stand for a preset time, and then the activated carbon sheet is taken out from the bonding chamber, comprising:

[0024] removing the first activated carbon sheet from the bonding chamber;

[0025] Bonding a first wafer and a second wafer in a bonding chamber to obtain a bonded wafer includes:

[0026] A first wafer is placed on a loading station of a bonding chamber.

[0027] As an optional implementation manner, after the activated carbon sheet is allowed to stand for a preset time, removing the activated carbon sheet from the bonding chamber comprises:

[0028] removing the first activated carbon sheet from the bonding chamber;

[0029] Bonding a first wafer and a second wafer in a bonding chamber to obtain a bonded wafer includes:

[0030] Disposing a first wafer on a loading station of a bonding chamber;

[0031] An activation gun is used to irradiate the first wafer and form an activation layer on the surface of the first wafer, and the second activated carbon sheet absorbs particulate matter generated by the first wafer.

[0032] As an optional implementation manner, after irradiating the first wafer with an activation gun and forming an activation layer on the surface of the first wafer, and the second activated carbon sheet adsorbing particulate matter generated by the first wafer, and after allowing the activated carbon sheet to stand for a preset time, removing the activated carbon sheet from the bonding chamber comprises:

[0033] removing the second activated carbon sheet from the bonding chamber;

[0034] Bonding a first wafer and a second wafer in a bonding chamber to obtain a bonded wafer includes:

[0035] A second wafer is placed on the upper electrostatic chuck of the bonding chamber.

[0036] As an optional embodiment, the irradiating the activated carbon sheet with an activation gun to introduce active functional groups on the surface of the activated carbon sheet and change the pore structure of the activated carbon sheet includes:

[0037] The activated carbon sheet is irradiated multiple times with an activation gun, and the interval between two adjacent irradiations is 200-400s to control the temperature of the activated carbon sheet.

[0038] As an optional embodiment, the irradiating the activated carbon sheet with an activation gun to introduce active functional groups on the surface of the activated carbon sheet and change the pore structure of the activated carbon sheet includes:

[0039] When the activation gun irradiates the activated carbon sheet, the voltage is 1-3 kV, the current is 100-300 mA, the argon flow rate is 30-50 sccm, and the irradiation time is 500-700 s.

[0040] The beneficial effects of the embodiments of the present application include:

[0041] A wafer bonding method provided in an embodiment of the present application includes: placing an activated carbon sheet in a bonding chamber; the embodiment of the present application uses an activation gun to irradiate the activated carbon sheet, which can make the pore structure of the activated carbon sheet more regular, increase the effective specific surface area of ​​the activated carbon sheet, and improve its adsorption efficiency. On the other hand, the activated carbon sheet is irradiated with an activation gun, and new chemical groups such as hydroxyl groups and carboxyl groups are formed on the surface of the activated carbon sheet, and the introduced active functional groups can react chemically with organic pollutants. The activated carbon sheet used in the embodiment of the present application can not only effectively adsorb tiny particles and organic pollutants in the bonding chamber, but also adsorb tiny particles and organic pollutants released by the first wafer and the second wafer before bonding activation. Therefore, the embodiment of the present application can greatly improve the environmental cleanliness during the bonding operation, thereby improving the quality and consistency of wafer bonding and achieving an improvement in the yield of the bonding operation. BRIEF DESCRIPTION OF THE DRAWINGS

[0042] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings required for use in the embodiments will be briefly introduced below. It should be understood that the following drawings only show certain embodiments of the present application and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other related drawings can be obtained based on these drawings without paying creative work.

[0043] Figure 1 This is a schematic diagram of using an activation gun to irradiate an activated carbon sheet in an embodiment of the present application;

[0044] Figure 2 This is a schematic diagram of the activated carbon sheet adsorbing particulate matter and pollutants according to an embodiment of the present application;

[0045] Figure 3 This is a schematic diagram of the third activated carbon sheet in the embodiment of the present application absorbing particulate matter generated by the activation of the first wafer and the second wafer;

[0046] Figure 4 This is a schematic diagram of the first activated carbon sheet adsorbing particulate matter generated by the activation of the second wafer in the embodiment of the present application;

[0047] Figure 5 This is a schematic diagram of the second activated carbon sheet in the embodiment of the present application absorbing particulate matter generated by activation of the first wafer;

[0048] Figure 6 This is a schematic diagram of bonding the first wafer and the second wafer according to an embodiment of the present application.

[0049] icon:

[0050] 100 - downloading platform; 101 - first activated carbon sheet; 102 - upper electrostatic suction cup; 103 - second activated carbon sheet; 104 - first wafer; 105 - second wafer; 106 - third activated carbon sheet; 107 - activation gun. DETAILED DESCRIPTION

[0051] In order to make the purpose, technical solution and advantages of the embodiments of the present application clearer, the technical solution in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are part of the embodiments of the present application, rather than all the embodiments. The components of the embodiments of the present application described and shown in the drawings here can be arranged and designed in various different configurations.

[0052] Therefore, the following detailed description of the embodiments of the present application provided in the accompanying drawings is not intended to limit the scope of the present application for which protection is sought, but merely represents selected embodiments of the present application. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in the field without creative work are within the scope of protection of the present application.

[0053] Wafer bonding is a key technology in the semiconductor manufacturing process, which involves precisely bonding two or more wafers together. Tiny particles are prone to exist in vacuum chambers with poor cleanliness. These particles will be sandwiched between the two wafers during the bonding process, resulting in poor contact in local areas, thus forming voids or defects, affecting the bond strength, and may cause failures in subsequent process steps. In addition to the above problems, wafer bonding chambers with poor cleanliness can also lead to problems including chemical contamination, improper humidity control, electrostatic adsorption, and bonding interface defects. These problems work together to significantly reduce the quality and consistency of bonding, ultimately leading to a significant reduction in bonding yield.

[0054] In order to solve the above technical problems, an embodiment of the present application provides a wafer bonding method.

[0055] An embodiment of the present application provides a wafer bonding method, comprising:

[0056] Reference Figure 1 As shown, an activated carbon sheet is placed in the bonding chamber;

[0057] The activated carbon sheet is irradiated with an activation gun 107 to introduce active functional groups on the surface of the activated carbon sheet and change the pore structure of the activated carbon sheet;

[0058] Reference Figure 2 As shown, after the activated carbon sheet is left to stand for a preset time, the activated carbon sheet is taken out from the bonding chamber;

[0059] Reference Figure 6 As shown, the first wafer 104 and the second wafer 105 are bonded in a bonding chamber to obtain a bonded wafer.

[0060] It should be noted that the embodiment of the present application places an activated carbon sheet in the bonding chamber. The activated carbon has a highly developed pore structure and a huge specific surface area, and can effectively absorb tiny particles, chemical pollutants, and moisture in the air. The embodiment of the present application places the activated carbon sheet in the bonding chamber to ensure that it can cover the area where pollution occurs, thereby improving the cleanliness of the bonding chamber environment.

[0061] The present application irradiates the activated carbon sheet through the activation gun 107, and the emission of ion beams or plasma to the activated carbon sheet can introduce active functional groups on its surface and change the pore structure of the activated carbon sheet, thereby enhancing its adsorption capacity. On the one hand, the above-mentioned treatment makes the pore structure of the activated carbon more regular, increases the effective specific surface area, and improves the adsorption efficiency. On the other hand, new chemical groups such as hydroxyl and carboxyl groups are formed on the surface of the activated carbon sheet, and these functional groups can react chemically with some organic pollutants to achieve the treatment of organic pollutants.

[0062] The embodiment of the present application allows the activated carbon sheet enough time to adsorb pollutants in the chamber, ensuring that the chamber reaches a high degree of cleanliness. This includes both direct adsorption of particulate matter by the activated carbon sheet and reaction treatment between active functional groups and organic pollutants. Wafer bonding is performed in a clean environment after purification to ensure that the bonding interface is free of contamination, thereby improving bonding quality and yield.

[0063] It should be noted that before bonding the first wafer 104 and the second wafer 105, an activation gun 107 is required to irradiate the first wafer 104 and the second wafer 105. The ion beam emitted by the activation gun 107 bombards the wafer surface and generates a large number of tiny particles. The activated carbon sheet of the embodiment of the present application can not only process the original particulate matter and organic pollutants in the bonding chamber, but also adsorb the particulate matter generated when the first wafer 104 and the second wafer 105 are activated.

[0064] The beneficial effects of the embodiments of the present application are as follows:

[0065] First, significantly improve cleanliness: Activated carbon sheets can efficiently absorb tiny particles in the air, reducing voids or defects caused by particle inclusions during the bonding process. The active functional groups introduced on the surface of activated carbon can react with chemical pollutants such as organic matter and metal ions to further purify the chamber environment. Activated carbon has good hygroscopic properties, which helps to regulate the humidity in the chamber and prevent moisture from affecting the bonding quality.

[0066] Second, enhance electrostatic protection: Activated carbon sheets have a certain conductivity, which can help release static charges, reduce electrostatic adsorption effects, and reduce the risk of particle contamination. The presence of activated carbon sheets can shield external electrostatic fields to a certain extent and protect wafers from electrostatic damage.

[0067] Third, improve the quality of the bonding section: The bonding chamber that has been purified by activated carbon sheets can provide an extremely clean environment for wafer bonding, ensuring that there are no impurities on the bonding interface and achieving uniform and strong bonding. Since the influence of particle contamination and other contaminants is eliminated, the defects of the bonding interface are significantly reduced, and the bonding strength and reliability are greatly improved. In addition, stable cleanliness helps to reduce quality fluctuations between different batches of products and improve overall production efficiency and yield rate.

[0068] Furthermore, the activated carbon sheet is irradiated with an activation gun 107 to introduce active functional groups on the surface of the activated carbon sheet and change the pore structure of the activated carbon sheet, including:

[0069] The activated carbon sheet is irradiated multiple times by the activation gun 107, and the interval between two adjacent irradiations is 200-400s to control the temperature of the activated carbon sheet. The above configuration can effectively prevent the activated carbon sheet from being damaged due to excessive temperature, thereby ensuring the safety and reliability of the activated carbon sheet.

[0070] It should be noted that those skilled in the art can set the number of times and the interval time of irradiating the activated carbon sheet by the activation gun 107 as needed. For example, the activation gun 107 is used to irradiate the activated carbon sheet twice, and the interval between the two adjacent irradiations is 300 seconds.

[0071] Furthermore, each time the activation gun 107 irradiates the activated carbon sheet, the voltage is 1-3 kV, the current is 100-300 mA, the argon flow rate is 30-50 sccm, and the irradiation time is 500-700 s.

[0072] Exemplarily, each time the activation gun 107 irradiates the activated carbon sheet, the voltage is 1.5 kV, the current is 150 mA, the argon flow rate is 40 sccm, and the irradiation time is 600 s.

[0073] Reference Figure 1 As shown, as an optional embodiment, placing an activated carbon sheet in the bonding chamber includes:

[0074] A first activated carbon sheet 101 is arranged on the surface of the unloading platform 100 of the bonding chamber; and a second activated carbon sheet 103 is laid on the upper electrostatic chuck 102 of the bonding chamber.

[0075] It should be noted that the embodiment of the present application uses the first activated carbon sheet 101 and the second activated carbon sheet 103 to be attached to the unloading platform 100 and the upper electrostatic chuck 102 respectively, which can achieve efficient adsorption and cleaning of the unloading platform 100 and the upper electrostatic chuck 102. The surface of the first activated carbon sheet 101 away from the unloading platform 100 can adsorb the particles suspended in the air of the bonding chamber, and the surface of the second activated carbon sheet 103 away from the upper electrostatic chuck 102 can also adsorb the particles suspended in the air of the bonding chamber.

[0076] As an optional implementation, bonding the first wafer 104 and the second wafer 105 in a bonding chamber to obtain a bonded wafer includes:

[0077] The first activation gun 107 and the second activation gun 107 are used to irradiate the first wafer 104 and the second wafer 105 respectively, so that activation layers are formed on the surfaces of the first wafer 104 and the second wafer 105;

[0078] The activation layer on the first wafer 104 is attached to the activation layer on the second wafer 105 , and the first wafer 104 and the second wafer 105 are pressure-bonded.

[0079] The bonding parameters can be set by those skilled in the art as required, and are not particularly limited thereto. For example, the bonding pressure can be set to 10000N and the pressing time to 30s.

[0080] In the embodiment of the present application, the first wafer 104 and the second wafer 105 are irradiated by the activation gun 107. The high-energy particle beam or plasma emitted by the activation gun 107 can effectively decompose and remove organic pollutants on the surface of the wafer, such as grease, residual photoresist, etc., to ensure a clean surface. Before wafer bonding, the irradiation of the activation gun 107 can be used for surface activation to promote chemical bonding or van der Waals interaction between the two wafers, thereby improving bonding strength and uniformity.

[0081] It should be noted that the activation layer may be formed only on the first wafer 104 , or may be formed only on the second wafer 105 .

[0082] Reference Figure 3 As shown, further, before using the first activation gun 107 and the second activation gun 107 to irradiate the first wafer 104 and the second wafer 105 respectively, the method further includes:

[0083] A third activated carbon sheet 106 is disposed between the first wafer 104 and the second wafer 105;

[0084] The activation gun 107 is used to emit plasma toward the third activated carbon sheet 106 .

[0085] It should be noted that, in the embodiment of the present application, a third activated carbon sheet 106 is disposed between the first wafer 104 and the second wafer 105, and the upper and lower surfaces of the third activated carbon sheet 106 can adsorb the tiny particles generated by the activation of the first wafer 104 and the second wafer 105. That is to say, the embodiment of the present application uses the third activated carbon sheet 106 for secondary adsorption to prevent the tiny particles generated by the activation of the first wafer 104 and the second wafer 105 from adhering to the bonding surface of the wafers, eliminating the adverse effects thereof on the wafer bonding, and ensuring the improvement of the wafer bonding yield.

[0086] Different from the above-mentioned embodiment, in the embodiment of the present application, after the activated carbon sheet is left to stand for a preset time, the activated carbon sheet is taken out from the bonding chamber, including:

[0087] Taking out the second activated carbon sheet 103 from the bonding chamber;

[0088] Bonding the first wafer 104 and the second wafer 105 in a bonding chamber to obtain a bonded wafer includes:

[0089] Disposing a second wafer 105 on an upper electrostatic chuck 102 of the bonding chamber;

[0090] Reference Figure 4 As shown, an activation gun 107 is used to irradiate the second wafer 105 and form an activation layer on the surface of the second wafer 105 , and the first activated carbon sheet 101 absorbs particulate matter generated by the second wafer 105 .

[0091] Further, after the second wafer 105 is irradiated with the activation gun 107 and an activation layer is formed on the surface of the second wafer 105, and the first activated carbon sheet 101 adsorbs particulate matter generated by the second wafer 105, the activated carbon sheet is left to stand for a preset time, and then the activated carbon sheet is taken out from the bonding chamber, including:

[0092] Taking out the first activated carbon sheet 101 from the bonding chamber;

[0093] Bonding the first wafer 104 and the second wafer 105 in a bonding chamber to obtain a bonded wafer includes:

[0094] A first wafer 104 is disposed on a unloading stage 100 of a bonding chamber.

[0095] Different from the above-mentioned embodiment, in the embodiment of the present application, after the activated carbon sheet is left to stand for a preset time, the activated carbon sheet is taken out from the bonding chamber, including:

[0096] Taking out the first activated carbon sheet 101 from the bonding chamber;

[0097] Bonding the first wafer 104 and the second wafer 105 in a bonding chamber to obtain a bonded wafer includes:

[0098] A first wafer 104 is arranged on a loading platform 100 of a bonding chamber;

[0099] Reference Figure 5 As shown, an activation gun 107 is used to irradiate the first wafer 104 and form an activation layer on the surface of the first wafer 104 , and the second activated carbon sheet 103 absorbs particulate matter generated by the first wafer 104 .

[0100] Further, after the activation gun 107 is used to irradiate the first wafer 104 and an activation layer is formed on the surface of the first wafer 104, and the second activated carbon sheet 103 adsorbs particulate matter generated by the first wafer 104, the activated carbon sheet is left to stand for a preset time, and then the activated carbon sheet is taken out from the bonding chamber, including:

[0101] Taking out the second activated carbon sheet 103 from the bonding chamber;

[0102] Bonding the first wafer 104 and the second wafer 105 in a bonding chamber to obtain a bonded wafer includes:

[0103] A second wafer 105 is disposed on the upper electrostatic chuck 102 of the bonding chamber.

[0104] A wafer bonding method provided in an embodiment of the present application includes: placing an activated carbon sheet in a bonding chamber; the embodiment of the present application uses an activation gun 107 to irradiate the activated carbon sheet, which can make the pore structure of the activated carbon sheet more regular, increase the effective specific surface area of ​​the activated carbon sheet, and improve its adsorption efficiency. On the other hand, the activated carbon sheet is irradiated with an activation gun 107, and new chemical groups such as hydroxyl groups and carboxyl groups are formed on the surface of the activated carbon sheet, and the introduced active functional groups can react chemically with organic pollutants. The activated carbon sheet used in the embodiment of the present application can not only effectively adsorb tiny particles and organic pollutants in the bonding chamber, but also adsorb tiny particles and organic pollutants released by the first wafer 104 and the second wafer 105 before bonding activation. Therefore, the embodiment of the present application can greatly improve the environmental cleanliness during the bonding operation, thereby improving the quality and consistency of wafer bonding and achieving an improvement in the yield of the bonding operation.

[0105] The above description is only the preferred embodiment of the present application and is not intended to limit the present application. For those skilled in the art, the present application may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application shall be included in the protection scope of the present application.

Claims

1. A wafer bonding method, characterized in that: include: An activated carbon sheet is placed in the bonding chamber; specifically, a first activated carbon sheet is placed on the surface of the unloading platform of the bonding chamber; and a second activated carbon sheet is placed on the upper electrostatic chuck of the bonding chamber; irradiating the activated carbon sheet with an activation gun to introduce active functional groups onto the surface of the activated carbon sheet and change the pore structure of the activated carbon sheet; After the activated carbon sheet is left to stand for a preset time, the activated carbon sheet is taken out from the bonding chamber; The first wafer and the second wafer are bonded in a bonding chamber to obtain a bonded wafer.

2. The wafer bonding method according to claim 1, characterized in that: The step of bonding the first wafer and the second wafer in a bonding chamber to obtain a bonded wafer includes: Using a first activation gun and a second activation gun to irradiate the first wafer and the second wafer respectively, so that activation layers are formed on the surfaces of the first wafer and the second wafer; The activation layer on the first wafer is laminated with the activation layer on the second wafer, and the first wafer and the second wafer are pressure-bonded.

3. The wafer bonding method according to claim 2, characterized in that: Before the first activation gun and the second activation gun are used to irradiate the first wafer and the second wafer respectively, the method further includes: Disposing a third activated carbon sheet between the first wafer and the second wafer; An activation gun is used to emit plasma toward the third activated carbon sheet.

4. The wafer bonding method according to claim 1, characterized in that: After the activated carbon sheet is allowed to stand for a preset time, taking out the activated carbon sheet from the bonding chamber comprises: removing the second activated carbon sheet from the bonding chamber; Bonding a first wafer and a second wafer in a bonding chamber to obtain a bonded wafer includes: placing a second wafer on an upper electrostatic chuck of the bonding chamber; An activation gun is used to irradiate the second wafer and an activation layer is formed on the surface of the second wafer, and the first activated carbon sheet absorbs particulate matter generated by the second wafer.

5. The wafer bonding method according to claim 4, characterized in that: After the second wafer is irradiated with an activation gun and an activation layer is formed on the surface of the second wafer, and the first activated carbon sheet adsorbs particulate matter generated by the second wafer, the activated carbon sheet is left to stand for a preset time, and then the activated carbon sheet is taken out from the bonding chamber, comprising: removing the first activated carbon sheet from the bonding chamber; Bonding a first wafer and a second wafer in a bonding chamber to obtain a bonded wafer includes: A first wafer is placed on a loading station of a bonding chamber.

6. The wafer bonding method according to claim 1, characterized in that: After the activated carbon sheet is allowed to stand for a preset time, taking out the activated carbon sheet from the bonding chamber comprises: removing the first activated carbon sheet from the bonding chamber; Bonding a first wafer and a second wafer in a bonding chamber to obtain a bonded wafer includes: Disposing a first wafer on a loading station of a bonding chamber; An activation gun is used to irradiate the first wafer and form an activation layer on the surface of the first wafer, and the second activated carbon sheet absorbs particulate matter generated by the first wafer.

7. The wafer bonding method according to claim 6, characterized in that: After the activation gun is used to irradiate the first wafer and an activation layer is formed on the surface of the first wafer, and the second activated carbon sheet adsorbs particulate matter generated by the first wafer, the activated carbon sheet is allowed to stand for a preset time, and then the activated carbon sheet is taken out from the bonding chamber, comprising: removing the second activated carbon sheet from the bonding chamber; Bonding a first wafer and a second wafer in a bonding chamber to obtain a bonded wafer includes: A second wafer is placed on the upper electrostatic chuck of the bonding chamber.

8. The wafer bonding method according to any one of claims 1 and 3-7, characterized in that: The step of irradiating the activated carbon sheet with an activation gun to introduce active functional groups onto the surface of the activated carbon sheet and change the pore structure of the activated carbon sheet comprises: The activated carbon sheet is irradiated multiple times with an activation gun, and the interval between two adjacent irradiations is 200-400s to control the temperature of the activated carbon sheet.

9. The wafer bonding method according to any one of claims 1 and 3-7, characterized in that: The step of irradiating the activated carbon sheet with an activation gun to introduce active functional groups onto the surface of the activated carbon sheet and change the pore structure of the activated carbon sheet comprises: When the activation gun irradiates the activated carbon sheet, the voltage is 1-3 kV, the current is 100-300 mA, the argon flow rate is 30-50 sccm, and the irradiation time is 500-700 s.

Images