Semiconductor device bonding method, laminated semiconductor device and electronic equipment

Abstract

The invention belongs to the technical field of semiconductors, and particularly discloses a method for bonding a semiconductor device, a laminated semiconductor device and electronic equipment, and the method comprises the steps: providing a first semiconductor device and a second semiconductor device, the first semiconductor device is provided with a first to-be-bonded surface, and the second semiconductor device is provided with a second to-be-bonded surface; at least one of the first to-be-bonded surface and the second to-be-bonded surface is in contact with a mixture containing ozone and unsaturated hydrocarbon gas, and then the first to-be-bonded surface and the second to-be-bonded surface are in contact bonding. Therefore, the bonding strength and the electrical connection effect of the semiconductor device can be improved.

Description

Technical Field

[0001] The present application belongs to the field of semiconductor technology, and specifically relates to a method for bonding semiconductor devices, a stacked semiconductor device and an electronic device. Background Art

[0002] In order to increase the number of semiconductor devices arranged per unit wafer area, stacked semiconductor devices came into being. In the preparation process of stacked semiconductor devices, the quality of packaging and bonding is one of the key factors affecting device performance. In the process of advanced packaging, the commonly used bonding methods are melt bonding and hybrid bonding, which still have the following problems: 1. The main use is the -OH provided by water, which forms Si-OH with the dangling bonds such as Si- and Si-O- of the chip or wafer, and then forms Si-O-Si chemical bonds through subsequent alignment, bonding, and annealing processes to complete the bonding. When the silicon dangling bonds are in contact with water molecules, due to the high activation energy required to form Si-OH bonds, the proportion of Si-OH formed at room temperature is low, affecting the final bonding strength; 2. The combination of water and oxygen in the air makes it easier for Cu at the bonding interface to oxidize, affecting the subsequent electrical connectivity effect; 3. In the subsequent annealing process, excess water molecules will form voids as desorption sites, resulting in reduced bonding strength; 4. Ar / N is used in the bonding process. 2 The gas performs plasma bombardment activation on the bonding interface. The plasma source is located in the same processing chamber as the substrate, which causes etching to occur in the chamber during the plasma generation process. Unlike conventional etching processes that are followed by ashing (Asher), wet cleaning (Wet Clean), etc., the dust, particles, and copper metal sputtering and other contaminants generated at this time will adhere to the bonding interface, thereby hindering the formation of a strong bond. Therefore, the method of bonding semiconductor devices still needs to be further improved. Summary of the invention

[0003] The present application aims to solve one of the technical problems in the related art at least to a certain extent. To this end, the present application proposes a method for bonding semiconductor devices with high bonding strength or good electrical connection effect, a stacked semiconductor device and an electronic device.

[0004] In a first aspect, the present application proposes a method for bonding semiconductor devices, comprising: providing a first semiconductor device and a second semiconductor device, wherein the first semiconductor device has a first surface to be bonded, and the second semiconductor device has a second surface to be bonded; contacting at least one of the first surface to be bonded and the second surface to be bonded with a mixture containing ozone and an unsaturated hydrocarbon gas, and then contacting and bonding the first surface to be bonded and the second surface to be bonded. Thus, the bonding strength and electrical connectivity of the semiconductor device can be improved.

[0005] In some embodiments, the mass concentration of the ozone is greater than 80%. Thus, it is beneficial to obtain a large number of -OH active free radicals.

[0006] In some embodiments, the unsaturated hydrocarbon gas includes at least one of ethylene, propylene and butene, thereby facilitating obtaining a large number of -OH active free radicals.

[0007] In some embodiments, the molar ratio of the ozone to the unsaturated hydrocarbon gas is 1:1 to 4:1. This is conducive to making the reaction more complete, thereby generating a large number of -OH active free radicals.

[0008] In some embodiments, before contacting with the mixture containing ozone and unsaturated hydrocarbon gas, the method further includes: performing remote plasma assisted treatment on at least one of the first surface to be bonded and the second surface to be bonded, thereby facilitating the formation of dangling bonds on the bonding surface, thereby improving the effect of subsequent hydrophilic bonding.

[0009] In some embodiments, the remote plasma assisted method uses N 2 Plasma.

[0010] In some embodiments, the first semiconductor device and the second semiconductor device are each independently a wafer or a chip.

[0011] In some embodiments, the first semiconductor device also includes a first electrical connector, which is disposed in a first via having an opening located on the first surface to be bonded; the second semiconductor device also includes a second electrical connector, which is disposed in a second via having an opening located on the second surface to be bonded; during the contact bonding, the first electrical connector contacts and bonds with the second electrical connector.

[0012] In some embodiments, the material of the first electrical connection member and the material of the second electrical connection member independently include at least one of copper and aluminum, thereby facilitating improving the bonding strength.

[0013] In some embodiments, the surface of the first electrical connector facing the second semiconductor device is the third surface to be bonded, and the surface of the second electrical connector facing the first semiconductor device is the fourth surface to be bonded, and the method further includes: forming a recessed portion on at least one of the third surface to be bonded and the fourth surface to be bonded, and the recessed portion is preferably in a shallow dish shape. Thus, space can be provided for the electrical connector to expand due to heat during the bonding process, that is, the electrical connector can fill the gap in the recessed portion when it expands due to heat, thereby achieving electrical connectivity between chips or wafers.

[0014] The second aspect of the present application proposes a method for bonding semiconductor devices, including: providing a first semiconductor device and a second semiconductor device, the first semiconductor device having a first surface to be bonded, and the second semiconductor device having a second surface to be bonded; performing remote plasma assisted treatment on at least one of the first surface to be bonded and the second surface to be bonded, and then contacting and bonding the first surface to be bonded and the second surface to be bonded. The present application adopts a remote plasma assisted method, which is helpful for the later formation of Si-OH structure, and this method will not have an etching effect like a conventional plasma activation process to generate pollution, so this method almost completely avoids the influence of etching effect pollution on the bonding effect.

[0015] The third aspect of the present application provides a stacked semiconductor device, which is prepared by the method described in the first aspect or the second aspect of the present application. Therefore, the stacked semiconductor device has a strong bonding strength.

[0016] The fourth aspect of the present application provides an electronic device, comprising the stacked semiconductor device described in the third aspect of the present application. Thus, the electronic device has high reliability in use. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 It is a flow chart of a method for bonding semiconductor devices according to an embodiment of the present application.

[0018] Figure 2A and Figure 2B It is a schematic diagram of the structure of a semiconductor device according to an embodiment of the present application.

[0019] Figure 3A and Figure 3B It is a schematic diagram of the structure of a semiconductor device according to an embodiment of the present application.

[0020] Figure 4 It is a flow chart of a method for bonding semiconductor devices according to an embodiment of the present application.

[0021] Figure 5 Schematic diagram of the contact angle test in the embodiment of the present application. DETAILED DESCRIPTION

[0022] The embodiments of the present application are described in detail below, and examples of the embodiments are shown in the accompanying drawings. The embodiments described below with reference to the accompanying drawings are exemplary and are intended to be used to explain the present application, but cannot be understood as limiting the present application.

[0023] In a first aspect, the present application provides a method for bonding a semiconductor device, referring to Figure 1The method includes: providing a first semiconductor device 10 and a second semiconductor device 20, wherein the first semiconductor device 10 has a first surface to be bonded 11, and the second semiconductor device 20 has a second surface to be bonded 21; contacting at least one of the first surface to be bonded 11 and the second surface to be bonded 21 with a mixture containing ozone and an unsaturated hydrocarbon gas, and then contacting and bonding the first surface to be bonded 11 and the second surface to be bonded 21.

[0024] The present application uses high concentration ozone gas to react with unsaturated hydrocarbon gas at room temperature to generate -OH active free radicals. This reaction does not require heating and can react to generate -OH active free radicals at room temperature. -OH free radicals are extremely active and will directly react with the silicon dangling bonds on the surface to be bonded to generate Si-OH structures (for details, please refer to Figure 1 ), Si-OH+HO-Si→Si-O-Si+H occurs during bonding 2 O hydrophilic bonding reaction, thereby completing the bonding process. Compared with the original water molecules, the formation of Si-OH requires high activation energy, and the probability of occurrence at room temperature is very low. Using the above method of the present application, under the same surface structure to be bonded, more Si-OH structures are generated, which better guarantees the subsequent hydrophilic bonding strength.

[0025] Herein, there is no particular limitation on the specific types of the first semiconductor device and the second semiconductor device, for example, they may be wafers or chips. It is understood that a wafer refers to a silicon wafer used for the manufacture of silicon semiconductor integrated circuits. Because of its circular shape, it is called a wafer. Various circuit element structures can be processed on the silicon wafer to become an integrated circuit (IC) product with specific electrical functions. A chip, also known as an integrated circuit, is a device that integrates multiple electronic components (such as transistors, capacitors, resistors, etc.) on a single semiconductor chip to achieve specific circuit functions.

[0026] It can be understood that the bonding of the first semiconductor device and the second semiconductor device may include melt bonding and hybrid bonding. Specifically, melt bonding serves as a structural connection between semiconductor devices, and the material of the surface to be bonded is usually a dielectric film layer, including but not limited to silicon oxide, silicon nitride, silicon carbonitride, etc. Hybrid bonding serves as a structural and electrical connection between semiconductor devices. In addition to the dielectric film layer commonly used in melt bonding, the material of the surface to be bonded also includes an electrical connector (usually a metal material, such as copper, aluminum, etc.). During the hybrid bonding process, it is necessary to ensure that the dielectric film layers are aligned with the dielectric film layers, and the electrical connectors are aligned with the electrical connectors. In this way, it can be ensured that the electrical properties between the semiconductor devices can be successfully connected while the bonding strength meets the requirements.

[0027] As an example, the method for bonding semiconductor devices proposed in the present application can be melt bonding or hybrid bonding. Based on this, in some embodiments, the surfaces to be bonded of the first semiconductor device and the second semiconductor device can only have a dielectric film layer; in other embodiments, the surfaces to be bonded of the first semiconductor device and the second semiconductor device have a dielectric film layer and an electrical connector. As a specific example, refer to Figure 2A and Figure 2B The first semiconductor device 10 includes a first electrical connector 12, which is arranged in a first via 13 with an opening located on the first surface to be bonded 11; the second semiconductor device 20 also includes a second electrical connector 22, which is arranged in a second via 23 with an opening located on the second surface to be bonded 21; during the contact bonding, the first electrical connector 12 contacts and bonds with the second electrical connector 22.

[0028] In some embodiments, the material of the first electrical connector and the material of the second electrical connector are independently metal, specifically at least one of copper and aluminum, thereby ensuring a good electrical connection effect and improving the bonding strength.

[0029] In some embodiments, the mass concentration of ozone is greater than 80%, for example, 81%, 82%, 83%, 84%, 85%, 86%, 87%, 88%, 89% or 90%, etc. Thus, it is beneficial to obtain a large number of -OH active free radicals at room temperature, thereby effectively improving the bonding strength under mild conditions.

[0030] In some embodiments, the unsaturated hydrocarbon gas includes at least one of ethylene, propylene and butene (including 1-butene, 2-butene (cis and trans), isobutylene (2-methyl-1-propylene), etc.). As an example, the reaction equation of ozone and ethylene at room temperature is as follows: 3 + C 2 H 4 →CH 2 O + -OH + HCO. This is conducive to obtaining a large number of -OH active free radicals, thereby effectively improving the bonding strength.

[0031] In some embodiments, the molar ratio of the ozone to the unsaturated hydrocarbon gas is 1:1-4:1, specifically 1:1, 1.5:1, 2:1, 2.5:1, 3:1, 3.5:1, 4:1, etc. This is conducive to making the reaction more complete, thereby generating a large number of -OH active free radicals.

[0032] In some embodiments, before contacting with the mixture containing ozone and unsaturated hydrocarbon gas, referring to Figure 3A and Figure 3B The method further includes: performing remote plasma assisted processing on at least one of the first surface to be bonded and the second surface to be bonded.

[0033] Specifically, remote plasma assisted technology involves generating plasma in an area far away from the main processing chamber and then transferring the plasma to the surface area to be processed in a specific way. This technology can excite the gas to form plasma through radio frequency or microwaves.

[0034] Compared with plasma bombardment, the remote plasma-assisted method used in this application can form more dangling bonds on the surface to be bonded, which is conducive to the subsequent formation of Si-OH structure, thereby improving the bonding strength. At the same time, the degree of plasma etching on the surface to be bonded is relatively less, and the dust, particles, copper metal sputtering and other pollutants generated are also less, so there are fewer substances attached to the surface to be bonded, that is, the remote plasma-assisted method will not cause pollution due to the etching effect like the conventional plasma bombardment activation process. Therefore, this method almost completely avoids the impact of pollution on the bonding effect and has little impact on the subsequent bonding effect. And when the surface to be bonded has an electrical connector, the remote plasma-assisted method can also protect the electrical connector from oxidation, thereby improving the effect of electrical connectivity.

[0035] In some embodiments, the remote plasma assisted method uses N 2 Plasma. As a result, the effect of generating hanging bonds and protecting electrical connectors is better. Taking the material of the electrical connector as copper as an example, N 2 Ionization can generate Cu on the Cu surface 4 N can better protect Cu from subsequent oxidation, and during contact bonding, Cu 4 N can be decomposed to generate Cu, and metal bonds are formed between the electrical connectors on the first semiconductor device and the second semiconductor device to form an electrical connection.

[0036] In some embodiments, before or after the remote plasma assistance, a plasma bombardment with a relatively low intensity may be performed, which can increase the number of dangling bonds and reduce the etching of the bonding surface, thereby improving the bonding strength.

[0037] In some embodiments, when the first semiconductor device and the second semiconductor device have electrical connectors, the electrical connectors may be surface treated before the remote plasma assisted treatment to form a recessed structure on the surface of the electrical connectors. This is because the electrical connectors will expand due to heat during the subsequent contact bonding process, and the pre-formed recessed structure can provide space for the subsequent expansion in advance, thereby achieving better bonding.

[0038] As an example, the surface of the first electrical connector facing the second semiconductor device is the third surface to be bonded, and the surface of the second electrical connector facing the first semiconductor device is the fourth surface to be bonded. A recessed portion may be formed on at least one of the third surface to be bonded of the first electrical connector and the fourth surface to be bonded of the second electrical connector. In some specific examples, the recessed portion may be in the shape of a shallow dish. Thus, when the electrical connector expands due to heat, the gap in the recessed portion may be filled, thereby achieving electrical connectivity between the semiconductor devices.

[0039] In some embodiments, a surface chemical mechanical planarization (CMP) process may be used to make the surface of the electrical connection member into a dishing morphology. The structural diagram is shown in FIG. Figure 3A and Figure 3B .

[0040] It is understood that the specific steps of contact bonding are not particularly limited. Specifically, the first semiconductor device and the second semiconductor device can be aligned and contact bonded. The specific operation steps and parameters can be performed with reference to conventional techniques in the art or flexibly adjusted and selected according to actual production conditions.

[0041] In addition, a first semiconductor device and a second semiconductor device are described herein, but the number of bonded semiconductor devices is not limited to 2, and multiple (including but not limited to 3, 4, 5, 6, 7, 8, etc.) semiconductor devices can be bonded together.

[0042] The following takes hybrid bonding, that is, the case where the surfaces to be bonded of the first semiconductor device and the second semiconductor device have a dielectric film layer and a copper electrical connection as an example to illustrate the method of bonding semiconductor devices of the present application, with reference to Figure 4 , specifically including: 1. Use the surface chemical mechanical planarization (CMP) process to make the surface to be bonded of the copper electrical connector into a shallow dishing morphology.

[0043] 2. Performing remote plasma assisted treatment on the surfaces to be bonded of the first semiconductor device and the second semiconductor device to form dangling bonds on the surfaces to be bonded, and generating Cu on the surfaces of the copper electrical connectors. + Active bond, Cu + Active bond and N 3- Ions combine to form Cu 3 N, free Cu atoms are doped into Cu 3 N lattice, forming Cu 4 The N structure can serve as a surface oxidation barrier to protect copper electrical connectors from oxidation.

[0044] 3. A mixture of ozone and unsaturated hydrocarbon gas with a mass concentration greater than 80% is brought into contact with the surface to be bonded. Ozone and unsaturated hydrocarbon gas can react at room temperature to generate a large number of active -OH free radicals. The active -OH free radicals can attach to the surface to be bonded under the action of an alternating current device and form a Si-OH structure with dangling bonds.

[0045] 4. Align the first semiconductor device and the second semiconductor device and contact and bond them. The following reaction occurs during the contact bonding process: Si-OH+HO-Si→Si-O-Si+H 2 O, while Cu 4 N has a high formation enthalpy (13.23 eV) and is in a metastable state. It can be decomposed at a high temperature of 200°C~300°C, thereby forming an atomic-level bond between Cu-Cu and completing the bonding process.

[0046] The second aspect of the present application proposes a method for bonding semiconductor devices, comprising: providing a first semiconductor device and a second semiconductor device, the first semiconductor device having a first surface to be bonded, and the second semiconductor device having a second surface to be bonded; performing remote plasma assisted treatment on at least one of the first surface to be bonded and the second surface to be bonded, and then contacting and bonding the first surface to be bonded and the second surface to be bonded. The present application adopts a remote plasma assisted method, which is helpful for the later formation of Si-OH structure, and this method will not have an etching effect like a conventional plasma activation process to produce pollution, so this method almost completely avoids the influence of etching effect pollution on the bonding effect. Furthermore, when the surface to be bonded has an electrical connector, remote plasma assistance can also protect the electrical connector from oxidation, thereby improving the electrical connectivity effect during bonding.

[0047] As a specific example, taking the case where the surfaces to be bonded of the first semiconductor device and the second semiconductor device have a dielectric film layer and a copper electrical connection member as an example, the method can be performed by the following method: 1. Use the surface chemical mechanical planarization (CMP) process to make the surface to be bonded of the copper electrical connector into a shallow dishing morphology.

[0048] 2. Performing remote plasma assisted treatment on the surfaces to be bonded of the first semiconductor device and the second semiconductor device to form dangling bonds on the surfaces to be bonded, and forming Cu on the surfaces to be bonded of the copper electrical connector. 4 N, to protect it from oxidation.

[0049] 3. Apply water evenly on the surface to prepare for hydrophilic bonding. Align the first semiconductor device and the second semiconductor device and bond them. After bonding, perform annealing at 200℃~350℃. For the dielectric layer, annealing can promote the formation of chemical bonds and enhance the chemical strength (hydrophilic bonding reaction formula: Si-OH+HO-Si→Si-O-Si+H 2 O); for metallic copper, Cu 4 N decomposes to generate Cu, and Cu expands due to heat, filling the gaps in the original bonded Dishing morphology, thereby achieving electrical connection between the first semiconductor device and the second semiconductor device.

[0050] It can be understood that the first semiconductor device, the second semiconductor device, the specific parameters of the remote plasma assisted processing, etc. used in the method can be consistent with the previous description and will not be repeated here.

[0051] The third aspect of the present application provides a stacked semiconductor device, which is prepared by the method described in the first aspect or the second aspect of the present application. Therefore, the stacked semiconductor device has a strong bonding strength.

[0052] In some embodiments, there is no particular limitation on the specific type of the stacked semiconductor device. As an example, the stacked semiconductor device includes but is not limited to a CIS image sensor chip, an NMC near memory computing chip, an HBM chip, and the like.

[0053] The fourth aspect of the present application provides an electronic device, comprising the stacked semiconductor device described in the third aspect of the present application. Thus, the electronic device has a higher circuit density, can realize more complex functions, and has better reliability.

[0054] In some embodiments, the specific type of the electronic device is not particularly limited. As an example, the electronic device includes but is not limited to an image sensor, a high-bandwidth memory, a high-computing chip, and the like.

[0055] The technical solution of this application has at least the following beneficial effects: 1. The original water is replaced by ozone and unsaturated hydrocarbon gas to generate -OH active free radicals at room temperature, thereby significantly increasing the density of generated Si-OH and improving the strength of subsequent hydrophilic bonding; 2. There is no step of applying water, that is, there is no water involved, which avoids the formation of cavities at the desorption sites of excess water molecules in the later stage, which affects the bonding effect. At the same time, there is no need for subsequent annealing and dehydration, and the annealing temperature and time can be reduced accordingly. In addition, because there is no water involved, the probability of Cu being oxidized is also reduced.

[0056] 3. Use remote plasma assistance to generate dangling bonds on the surface, which helps to form Si-OH later; 4. Use N in remote plasma assisted activation 2 It can ionize N ions and generate Cu on the surface of Cu 4 N protection structure to prevent copper from being oxidized; 5. Plasma-assisted treatment is used to generate -OH free radicals from ozone and unsaturated hydrocarbon gas at room temperature, replacing the original high-intensity plasma bombardment activation and water coating to provide -OH process, achieving a dust-free and water-free effect and improving the final bonding effect.

[0057] The embodiments of the present application are described in detail below.

[0058] Example 1 (1) Providing a semiconductor device having a via and a copper pad (i.e., an electrical connection member filled in the via) on the surface; (2) Using the surface chemical mechanical planarization (CMP) process, the copper on the surface to be bonded is made into a shallow dishing morphology; (3) Ozone gas with a mass concentration of 85% is reacted with ethylene at room temperature to generate a large number of active -OH radicals, and an alternating current device is added to the semiconductor device and the outlet of the reaction chamber to attach the -OH radicals to the surface to be bonded, forming a Si-OH structure with the dangling bonds; (4) High-precision alignment and hybrid bonding of semiconductor devices. After bonding is completed, the copper grains expand during furnace tube annealing to form electrical connections; (5) Test the bonding accuracy and ultrasonic bubble defects to verify the final bonding effect.

[0059] Example 2 (1) Providing a semiconductor device having a via and a copper pad (i.e., an electrical connection member filled in the via) on the surface; (2) Using the surface chemical mechanical planarization (CMP) process, the copper on the surface to be bonded is made into a shallow dishing morphology; (3) using remote plasma-assisted treatment to ionize nitrogen and form dangling bonds on the surface to be bonded; (4) High-precision alignment and hybrid bonding of semiconductor devices. After bonding is completed, the copper grains expand during furnace tube annealing to form electrical connections; (5) Test the bonding accuracy and ultrasonic bubble defects to verify the final bonding effect.

[0060] Example 3 (1) Providing a semiconductor device having a via and a copper pad (i.e., an electrical connection member filled in the via) on the surface; (2) Using the surface chemical mechanical planarization (CMP) process, the copper on the surface to be bonded is made into a shallow dishing morphology; (3) using remote plasma-assisted treatment to ionize nitrogen and form dangling bonds on the surface to be bonded; (4) Ozone gas with a mass concentration of 90% is reacted with ethylene at room temperature to generate a large number of active -OH radicals, and an alternating current device is added to the semiconductor device and the outlet of the reaction chamber to attach the -OH radicals to the surface to be bonded of the semiconductor device to form a Si-OH structure with the dangling bonds; (5) High-precision alignment and hybrid bonding of semiconductor devices. After bonding is completed, the copper grains expand during furnace tube annealing to form electrical connections; (6) Test the bonding accuracy and ultrasonic bubble defects to verify the final bonding effect.

[0061] Comparative Example 1 (1) Providing a semiconductor device having a via and a copper pad (i.e., an electrical connection member filled in the via) on the surface; (2) Using the surface chemical mechanical planarization (CMP) process, the copper on the surface to be bonded is made into a shallow dishing morphology; (3) Pickling with citric acid to remove impurities on the surface to be bonded and oxides on the copper surface; (4) Use Ar / N 2 The mixed gas is subjected to plasma bombardment to form dangling bonds; (5) The surface is evenly coated with water to prepare for hydrophilic bonding; (6) High-precision alignment and hybrid bonding of semiconductor devices. After bonding is completed, the copper grains are expanded by furnace tube annealing to form electrical connections; (7) Test the bonding accuracy and ultrasonic bubble defects to verify the final bonding effect.

[0062] Performance testing: Bonding accuracy: measured by a bonding overlay accuracy measuring machine.

[0063] Ultrasonic bubble defects: Ultrasonic bubble detection uses an ultrasonic scanning microscope C-SAM machine to scan the bubble defects between the wafers after bonding.

[0064] Contact angle: Drop a droplet on the treated bonding interface, take a side image, and then measure the angle. See the test diagram for details. Figure 5 , where θ is the contact angle.

[0065] Bond strength: 1) Insert a blade between two bonded wafers to create a gap between the two wafers; 2) Use an infrared device to measure the gap length L; (3) Calculate the bond strength using the gap length and the following formula.

[0066]

[0067] Wherein, γ is used to represent the bonding strength; E 1 Used to represent the Young's modulus of the upper wafer in the bonded wafer; E 2 Used to represent the Young's modulus of the wafer below the bonded wafer; t 1 It is used to indicate the thickness of the upper wafer in the bonded wafer; t 2 It is used to indicate the thickness of the wafer at the bottom of the bonded wafer; L is used to indicate the length of the gap; A t Used to indicate the total wafer area; A b Used to indicate the area of ​​the wafer bonding portion, h refers to the vertical distance separating the bonding interfaces of the two wafers after the blade is inserted.

[0068] Table 1

[0069] The bonding effects of the embodiments and comparative examples were tested, and as shown in Table 1, it was found that the stacked semiconductor device of the technical solution of the present application has higher bonding accuracy, fewer ultrasonic bubble defects, and higher bonding strength.

[0070] In the description of the present application, it should be understood that the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one of the features. In the description of the present application, the meaning of "plurality" is at least two, such as two, three, etc., unless otherwise clearly and specifically defined.

[0071] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "example", "specific example" or "some examples" etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present application. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art may combine and combine the different embodiments or examples described in this specification and the features of the different embodiments or examples, without contradiction.

[0072] Although the embodiments of the present application have been shown and described above, it can be understood that the above embodiments are exemplary and cannot be understood as limitations on the present application. Ordinary technicians in this field can change, modify, replace and modify the above embodiments within the scope of the present application.

Claims

1. A method for bonding semiconductor devices, characterized in that: include: Providing a first semiconductor device and a second semiconductor device, wherein the first semiconductor device has a first surface to be bonded, and the second semiconductor device has a second surface to be bonded; At least one of the first surface to be bonded and the second surface to be bonded is brought into contact with a mixture containing ozone and an unsaturated hydrocarbon gas, and then the first surface to be bonded and the second surface to be bonded are brought into contact and bonded.

2. The method according to claim 1, characterized in that: The mass concentration of ozone is greater than 80%; and / or The unsaturated hydrocarbon gas comprises at least one of ethylene, propylene and butene; and / or The molar ratio of the ozone to the unsaturated hydrocarbon gas is 1:1 to 4:

1.

3. The method according to claim 1, characterized in that Before contacting with the mixture containing ozone and unsaturated hydrocarbon gas, the method further comprises: A remote plasma assisted process is performed on at least one of the first surface to be bonded and the second surface to be bonded.

4. The method according to claim 3, characterized in that The remote plasma assisted processing uses N2 plasma.

5. The method according to claim 1, characterized in that The first semiconductor device and the second semiconductor device are each independently a wafer or a chip.

6. The method according to any one of claims 1 to 5, characterized in that The first semiconductor device further comprises a first electrical connection member, wherein the first electrical connection member is disposed in a first via hole whose opening is located on the first surface to be bonded; The second semiconductor device further comprises a second electrical connection member, wherein the second electrical connection member is arranged in a second via hole whose opening is located on the second surface to be bonded; During the contact bonding, the first electrical connection component contacts and bonds with the second electrical connection component.

7. The method according to claim 6, characterized in that The material of the first electrical connection component and the material of the second electrical connection component independently include at least one of copper and aluminum.

8. The method according to claim 6, characterized in that The surface of the first electrical connection member facing the second semiconductor device is a third surface to be bonded, and the surface of the second electrical connection member facing the first semiconductor device is a fourth surface to be bonded. The method further includes: A recessed portion is formed on at least one of the third surface to be bonded and the fourth surface to be bonded.

9. The method according to claim 8, characterized in that The recessed portion is in a shallow dish shape.

10. A method for bonding semiconductor devices, characterized in that: include: Providing a first semiconductor device and a second semiconductor device, wherein the first semiconductor device has a first surface to be bonded, and the second semiconductor device has a second surface to be bonded; A remote plasma assisted treatment is performed on at least one of the first surface to be bonded and the second surface to be bonded, and then the first surface to be bonded and the second surface to be bonded are brought into contact and bonded.

11. A stacked semiconductor device, characterized in that: It is prepared by the method according to any one of claims 1 to 10.

12. An electronic device, characterized in that: A stacked semiconductor device comprising the stacked semiconductor device according to claim 11.

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