Wafer bonding equipment

Abstract

The utility model provides wafer bonding equipment, which belongs to the technical field of wafer processing equipment and comprises a shell, a bonding seat and a heating device. A containing cavity is formed in the shell, and a base is arranged at the bottom of the containing cavity; the bonding seat is arranged on the base in the accommodating cavity, and the bonding seat is suitable for stacking wafers; the heating device is arranged on the base; the extrusion device and the bonding seat are oppositely arranged, and the wafers stacked on the bonding seat are pressurized through the extrusion device; according to the utility model, the heating device is arranged on the base below the bonding seat, so that when a certain bonding process needs high temperature, the temperature can be quickly raised through the heating device, and the production and processing requirements are met.

Description

Technical Field

[0001] The utility model relates to the technical field of wafer processing equipment, in particular to a wafer bonding device. Background Art

[0002] In the semiconductor production process, two or more wafers need to be stacked together, and physical and chemical methods are used to encourage the atoms or molecules between the bonding surfaces to penetrate each other and tightly combine. The atoms or molecules at the interface are affected by external energy, react to form covalent bonds, and combine into one, so that the bonding interface reaches a specific bonding strength to meet the needs of the process.

[0003] The Chinese patent document CN207367937U describes that it includes: a suction cup for fixing the wafer, and also includes: an airbag, a transducer and a controller. The airbag is installed in the suction cup for contacting the center of the wafer. The transducer is connected to the airbag for detecting the pressure in the airbag. The controller is connected to the transducer for adjusting the pressure in the airbag according to the detected pressure. The airbag squeezes the wafer so that the two wafers are bonded.

[0004] For some bonding processes, high-temperature bonding is required, but the equipment in the prior art does not have the bonding process under high-temperature conditions. Utility Model Content

[0005] Therefore, the technical problem to be solved by the present invention is to overcome the defect that the bonding equipment in the prior art is not capable of bonding wafers under high temperature conditions, thereby providing a wafer bonding equipment.

[0006] In order to solve the above technical problems, the utility model provides a wafer bonding device, comprising: a housing, a housing is provided in the housing, and a base is provided at the bottom of the housing;

[0007] A bonding seat, arranged on a base in the accommodating cavity, the bonding seat being suitable for stacking wafers;

[0008] A heating device is arranged on the base;

[0009] The extrusion device is arranged opposite to the bonding seat, and pressurizes the wafers stacked on the bonding seat through the extrusion device.

[0010] Preferably, a cooling channel is provided in the base, and the cooling channel is used to communicate with cooling water.

[0011] Preferably, the cooling channel is arranged in a disk shape and surrounded in the base.

[0012] Preferably, a temperature sensor is connected to the base.

[0013] Preferably, it also includes: a negative pressure device connected to the shell, the air inlet of the negative pressure device is connected to the accommodating chamber of the shell, and the negative pressure device is used to evacuate the accommodating chamber.

[0014] Preferably, the negative pressure device is connected to the accommodating chamber through a control valve.

[0015] Preferably, one end of the control valve away from the accommodating chamber is connected to a gas filling tube, and gas can be filled into the accommodating chamber in a vacuum state through the gas filling tube.

[0016] Preferably, the extrusion device includes: an airbag, a driving member and a mounting plate. The airbag is arranged on the lower end surface of the mounting plate. The lower surface of the airbag is used to contact the upper surface of the stacked wafers. The mounting plate drives the airbag to move toward the upper surface of the wafer under the drive of the driving member.

[0017] Preferably, the airbag is connected with an air inlet pipe, which is communicated with a nitrogen source.

[0018] Preferably, a plurality of guide columns are arranged in the shell, and the mounting plate slides along the guide columns in the shell.

[0019] The technical solution of the utility model has the following advantages:

[0020] 1. The wafer bonding equipment provided by the utility model has a heating device arranged on a base below the bonding seat. When a certain bonding process requires high temperature, the temperature can be quickly increased by the heating device to meet production and processing requirements.

[0021] 2. The wafer bonding equipment provided by the utility model has a cooling channel that can quickly cool the wafer after bonding, making it convenient to take out the bonded wafer.

[0022] 3. The wafer bonding equipment provided by the utility model is used to evacuate the containing chamber through a negative pressure device, and the vacuum can provide a clean environment for the wafer, avoiding the influence of other impurities on the wafer bonding during processing. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] In order to more clearly illustrate the specific implementation methods of the utility model or the technical solutions in the prior art, the drawings required for use in the specific implementation methods or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are some implementation methods of the utility model. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0024] Figure 1 This is a front view of a wafer bonding device provided in one embodiment of the utility model.

[0025] Description of reference numerals:

[0026] 1. Shell; 2. Accommodating cavity; 3. Base; 4. Bonding seat; 5. Heating device; 6. Cooling channel; 7. Temperature sensor; 8. Negative pressure device; 9. Driving member; 10. Mounting plate; 11. Airbag; 12. Pressure-controlled valve; 13. Control valve; 14. Inflating tube; 15. Wafer; 16. Inlet pipe; 17. Controller; 18. Guide column; 19. Inlet port. DETAILED DESCRIPTION

[0027] The technical solution of the utility model will be described clearly and completely below in conjunction with the accompanying drawings. Obviously, the described embodiments are part of the embodiments of the utility model, not all of the embodiments. Based on the embodiments of the utility model, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the utility model.

[0028] In the description of the present invention, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc., indicating the orientation or positional relationship, are based on the orientation or positional relationship shown in the drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as limiting the present invention. In addition, the terms "first", "second", and "third" are used for descriptive purposes only, and cannot be understood as indicating or implying relative importance.

[0029] In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "installation", "connection" and "connection" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0030] In addition, the technical features involved in the different embodiments of the present invention described below can be combined with each other as long as they do not conflict with each other.

[0031] The wafer bonding equipment provided in this embodiment is used to apply external force to two or more wafers 15 to cause atoms or molecules to penetrate each other and react to form covalent bonds, thereby combining them into one.

[0032] like Figure 1As shown, a specific implementation of the wafer bonding device provided in this embodiment includes: a shell 1, a receiving chamber 2 is arranged inside the shell 1, and a base 3 is arranged at the bottom of the receiving chamber 2; a bonding seat 4 is arranged on the base 3 in the receiving chamber 2, and the bonding seat 4 is suitable for stacking wafers 15, that is, it can place two or more wafers 15; a heating device 5 is arranged on the base 3, located below the bonding seat 4, and is used to heat the wafer 15 before bonding; an extrusion device is arranged opposite to the bonding seat 4, that is, the extrusion device is arranged above the bonding seat 4, and the wafers 15 stacked on the bonding seat 4 are pressurized by the extrusion device, so that the atoms or molecules between the two or more wafers 15 penetrate each other, tightly combine, react to form covalent bonds, and combine into one. Usually, the adhesion of the wafer 15 is weak at room temperature. The weak bonds can be converted into covalent bonds through high temperature to achieve the maximum bonding strength. By arranging a heating device 5 on the base 3 under the bonding seat 4, when a certain bonding process requires high temperature, the heating device 5 can be used to quickly heat up to meet production and processing.

[0033] Specifically, the heating device 5 is connected to the controller 17, and the controller 17 can control the start and stop of the heating device 5. The heating device 5 is an electric heater.

[0034] like Figure 1 As shown, an implementation of the wafer bonding device provided in this embodiment is provided, a cooling channel 6 is provided in the base 3, and the cooling channel 6 is provided with a water inlet valve and a water outlet valve. One end of the water inlet valve is connected to the cooling water, and cold water flows into the cooling channel 6 in the base 3 to quickly cool the accommodating cavity 2 after production and processing. In addition, as an alternative implementation, the cooling channel 6 can be provided in the bonding seat 4.

[0035] like Figure 1 As shown, it is an implementation of the wafer bonding device provided in this embodiment, the cooling channel 6 is arranged in a disk shape in the base 3, and the disk shape allows the cold water to take away as much heat as possible, and the temperature of the accommodating cavity 2 is quickly cooled, which is convenient for subsequent processing. In addition, as an alternative implementation, the cooling channel 6 is not arranged in a coil, and multiple groups are arranged in parallel in the base 3. In addition, as an alternative implementation, the cooling channel 6 is arranged in the bonding seat 4.

[0036] like Figure 1As shown, it is an implementation manner of the wafer bonding device provided in this embodiment, a temperature sensor 7 is connected to the base 3, and the temperature sensor 7 can detect the temperature in the accommodating chamber 2. When the temperature sensor 7 detects that the temperature rises to the required temperature, the heating device 5 stops heating. In addition, as an alternative implementation manner, the temperature sensor 7 is arranged on the bonding seat 4. In addition, as an alternative implementation manner, the temperature sensor 7 may not be arranged, and the heating device 5 is arranged as an electric heater capable of setting an adjustable temperature threshold in the prior art. In addition, as an alternative implementation manner, the temperature sensor 7 may be arranged on the bonding seat 4.

[0037] Specifically, the temperature sensor 7 is connected to the controller 17. After the data detected by the temperature sensor 7 is transmitted to the controller 17, when the data reaches a threshold of the controller 17, the controller 17 controls the heating device 5 to stop heating.

[0038] like Figure 1 As shown, an implementation of the wafer bonding device provided in this embodiment also includes: a negative pressure device 8, the negative pressure device 8 is connected to the shell 1, and the air inlet 19 of the negative pressure device 8 is connected to the accommodating chamber 2 of the shell 1. The negative pressure device 8 is used to evacuate the accommodating chamber 2. The vacuum can provide a clean environment for the wafer 15 to avoid the influence of other impurities on the bonding of the wafer 15 during processing. In addition, as a replaceable implementation, when the negative pressure device 8 is not provided in the wafer bonding device, the bonding of the wafer 15 can also be achieved. Specifically, the negative pressure device 8 is a vacuum pump in the prior art.

[0039] like Figure 1 As shown, an implementation of the wafer bonding device provided in this embodiment, the housing 1 has an air inlet 19 connected to the accommodating chamber 2, and the negative pressure device 8 is connected to the air inlet 19 of the housing 1 through the control valve 13. When vacuuming is required, the negative pressure device 8 and the control valve 13 are opened; when the housing 1 meets the vacuum environment required for bonding, the negative pressure device 8 and the control valve 13 are closed. In addition, as an alternative implementation, the negative pressure device 8 is arranged in the housing 1, and an exhaust port is arranged on the housing 1, and the gas extracted by the negative pressure device 8 is discharged from the exhaust port to the outside of the housing 1.

[0040] like Figure 1As shown, an implementation mode of the wafer bonding device provided in this embodiment, the end of the control valve 13 away from the accommodating chamber 2 is connected to the gas filling tube 14, and the gas filling tube 14 can be used to fill the accommodating chamber 2 in a vacuum state. The gas filling tube 14 is connected to the control valve 13 of the air inlet 19, that is, the gas filling tube 14 is connected in parallel with the negative pressure device 8, and the gas filling tube 14 is connected to the control valve 13 through a valve. One end of the gas filling tube 14 is connected to a nitrogen source, and can fill the accommodating chamber 2 in a vacuum state with gas. Specifically, when it is necessary to evacuate the shell 1, close the valve of the gas filling tube 14, open the control valve 13, and open the negative pressure device 8 to evacuate; when it is necessary to fill the vacuum environment with nitrogen, close the negative pressure device 8, open the valve of the gas filling tube 14, and fill the shell 1 with nitrogen. In addition, as a replaceable implementation mode, the gas filling tube 14 is directly connected to the shell 1. In addition, as an alternative embodiment, when the gas filling tube 14 is not provided to fill the housing 1 with nitrogen, the wafer 15 can also be bonded in a vacuum environment.

[0041] like Figure 1 As shown, it is an implementation mode of the wafer bonding device provided in this embodiment, and the extrusion device includes: an airbag 11, a driving member 9 and a mounting plate 10. The airbag 11 is arranged on the lower end surface of the mounting plate 10, and a positioning column is arranged on the upper end surface of the airbag 11, and the positioning column is fixed to the lower end surface of the mounting plate 10, so as to fix the airbag 11 to the lower end of the mounting plate 10. The lower surface of the airbag 11 is used to contact the upper surface of the stacked wafers 15, and the mounting plate 10 drives the airbag 11 to move toward the upper surface of the wafer 15 under the drive of the driving member 9. Among them, the driving member 9 is a cylinder, and the cylinder is connected to the mounting plate 10. When the wafer 15 is placed on the bonding seat 4, the cylinder contracts and drives the mounting plate 10 and the airbag 11 to move toward the bonding seat 4. After the airbag 11 touches the base 3, the airbag 11 expands, and the pressure is squeezed onto the wafer 15. Under the action of pressure, the molecules and atoms between the multiple wafers 15 diffuse with each other to form covalent bonds to achieve bonding. In addition, as a replaceable embodiment, the extrusion device may also include: a suction cup, which is arranged at the lower end of the airbag 11. When the driving member 9 drives the airbag 11 to descend, the suction cup first contacts the wafer 15 to generate suction, and at the same time the suction cup fixes the wafer 15 to prevent the wafer 15 from shifting during extrusion. At the same time, the pressure of the airbag 11 indirectly acts on the wafer 15 through the suction cup.

[0042] like Figure 1 As shown, an implementation of the wafer bonding device provided in this embodiment is provided. An air inlet pipe 16 is connected to the airbag 11, and the air inlet pipe 16 is connected to the nitrogen source. The air inlet pipe 16 is connected to the nitrogen source to fill the airbag 11 with nitrogen to achieve the expansion of the airbag 11. The air inlet pipe 16 is a hose to facilitate the movement of the airbag 11. In addition, as an alternative implementation, a valve can be set on the air inlet pipe 16 to open or close it.

[0043] Specifically, an automatic pressure regulating valve is installed on the air inlet pipe 16, and the automatic pressure regulating valve is connected to the controller 17. The controller 17 can control the opening or closing of the automatic pressure regulating valve, thereby controlling the pressure after the airbag 11 contacts the wafer 15. The automatic pressure regulating valve can keep the nitrogen entering the airbag 11 at a certain pressure, ensure the stability of nitrogen filling, and avoid the instability of pressure causing the wafer 15 to be unable to bond.

[0044] like Figure 1 As shown, it is an implementation of the wafer bonding device provided in this embodiment, four guide posts 18 are arranged in the housing 1, and the four ends of the mounting plate 10 are connected to the guide posts 18, and can slide along the guide posts 18 in the housing 1 under the drive of the driving member 9. This makes the movement of the mounting plate 10 more stable. In addition, as an alternative implementation, two guide posts 18 can be provided.

[0045] Installation method of wafer bonding equipment: A base 3 is arranged in the accommodating cavity 2 of the shell 1, and the base 3 is arranged at the lower end of the shell 1, and a bonding seat 4 is arranged at the upper end of the base 3. Two or more wafers 15 can be placed on the upper end surface of the bonding seat 4. A guide column 18 is arranged on the shell 1, and the guide column 18 is arranged vertically so that the airbag 11 can approach or move away from the wafer 15 seat in the vertical direction. The airbag 11 is installed to the lower end of the mounting plate 10. The driving member 9 is connected to both ends of the mounting plate 10. An air inlet 19 is arranged on the shell 1, and the air inlet 19 is connected to the control valve 13, and the control valve 13 is connected to the negative pressure device 8. The control valve 13 is also connected to an air inlet valve, and the air inlet valve is connected to a nitrogen source.

[0046] During operation: two wafers 15 are placed on the upper end of the bonding seat 4, the control valve 13 is opened, the negative pressure device 8 is started, and the housing 1 is evacuated to provide a clean environment for the bonding of the wafers 15. The negative pressure device 8 is closed, the air inlet valve is opened, and nitrogen is filled into the housing 1. After the bonding conditions are met, the air inlet valve and the control valve 13 are closed respectively. The drive member 9 is started to drive the mounting plate 10 and the airbag 11 to move downward until the airbag 11 abuts against the upper end surface of the wafer 15. The air inlet pipe 16 is opened to fill nitrogen into the airbag 11. The airbag 11 expands downward under the action of pressure, exerting pressure on the wafer 15, and the molecules and atoms between the wafers 15 diffuse with each other to form covalent bonds to achieve bonding. For wafers 15 that need to be bonded at high temperatures, the controller 17 turns on the heating device 5 on the base 3, and the temperature after heating is detected by the temperature sensor 7. When the data detected by the temperature sensor 7 reaches the threshold in the controller 17, the heating is stopped. After bonding is completed, rapid cooling is required. At this time, the water inlet valve and the water outlet valve of the cooling channel 6 are opened to complete the cold water circulation, take away the heat, and achieve rapid cooling. Then the pressure control valve 12 is opened, and the driving part 9 drives the mounting plate 10 and the airbag 11 to move upward. The bonded wafer 15 can be removed.

[0047] Working principle of the wafer bonding equipment: The heating device 5 on the base 3 can increase the temperature inside the shell 1, and use the temperature sensor 7 for detection. When the required production and processing temperature is reached, the heating is stopped, allowing the extrusion device to bond the wafer 15 on the bonding seat 4.

[0048] Obviously, the above embodiments are merely examples for the purpose of clear explanation, and are not intended to limit the implementation methods. For those skilled in the art, other different forms of changes or modifications can be made based on the above description. It is not necessary and impossible to list all the implementation methods here. The obvious changes or modifications derived from these are still within the scope of protection of the present utility model.

Claims

1. A wafer bonding device, characterized in that: include: A shell (1), wherein a receiving chamber (2) is provided in the shell (1), and a base (3) is provided at the bottom of the receiving chamber (2); A bonding seat (4) is arranged on the base (3) in the accommodating cavity (2), and the bonding seat (4) is suitable for stacking wafers (15); A heating device (5) is arranged on the base (3); An extrusion device is arranged opposite to the bonding seat (4), and the wafers (15) stacked on the bonding seat (4) are pressurized by the extrusion device. A cooling channel (6) is arranged in the base (3), and the cooling channel (6) is used to communicate with cooling water.

2. The wafer bonding equipment according to claim 1, characterized in that: The cooling channel (6) is arranged in a disk shape and surrounds the base (3).

3. The wafer bonding equipment according to claim 1, characterized in that: The base (3) is connected to a temperature sensor (7).

4. The wafer bonding equipment according to claim 1, characterized in that: Also includes: A negative pressure device (8) is connected to the shell (1); an air inlet (19) of the negative pressure device (8) is in communication with the accommodating chamber (2) of the shell (1); and the negative pressure device (8) is used to evacuate the accommodating chamber (2).

5. The wafer bonding equipment according to claim 4, characterized in that: The negative pressure device (8) is connected to the accommodating chamber (2) via a control valve (13).

6. The wafer bonding equipment according to claim 5, characterized in that: One end of the control valve (13) away from the accommodating chamber (2) is connected to a gas filling pipe (14), and gas can be filled into the accommodating chamber (2) in a vacuum state through the gas filling pipe (14).

7. The wafer bonding equipment according to any one of claims 1 to 6, characterized in that: The extrusion device comprises: an airbag (11), a driving member (9) and a mounting plate (10); the airbag (11) is arranged on the lower end surface of the mounting plate (10); the lower surface of the airbag (11) is used to contact the upper surface of the stacked wafers (15); and the mounting plate (10) drives the airbag (11) to move toward the upper surface of the wafer (15) under the drive of the driving member (9).

8. The wafer bonding equipment according to claim 7, characterized in that: The air bag (11) is connected to an air intake pipe (16), and the air intake pipe (16) is in communication with a nitrogen source.

9. The wafer bonding equipment according to claim 7, characterized in that: A plurality of guide columns (18) are arranged in the housing (1), and the mounting plate (10) slides along the guide columns (18) in the housing (1).

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