Bonding device and bonding method

Abstract

A bonding device is provided with: a stage (141) that holds a substrate (W1); a head (142) that is disposed so as to face the stage (141) and that holds the substrate (W2); and a particle beam source (161, 162) that radiates a particle beam to a region including a part of the bonding surface of the substrates (W1, W2). Next, the particle beam sources (161, 162) have a plurality of emission ports arranged in a direction along the bonding surface of the substrates (W1, W2) to which the particle beam is irradiated, and the opening area of each of the plurality of emission ports is set so as to become larger as the emission ports are arranged at positions farther from the center of the discharge chamber in the longitudinal direction.

Description

Technical Field

[0001] The present invention relates to a bonding device and a bonding method. Background Art

[0002] The following method has been proposed: after irradiating a particle beam to the bonding surfaces of a pair of substrates to perform a surface activation treatment to activate the bonding surfaces of the pair of substrates respectively, the bonding surfaces of the pair of substrates are brought into contact with each other to bond the pair of substrates to each other (for example, see Patent Document 1). In this method, in a chamber, stages that respectively hold a pair of substrates are arranged in a mutually separated state, and a particle beam is irradiated from a particle beam source fixed at a fixed position in the chamber to the bonding surfaces of the substrates held on the stages to activate the bonding surfaces of the substrates.

[0003] Prior art literature

[0004] Patent Literature

[0005] Patent Document 1: Japanese Patent Application Publication No. 2015-8228 Summary of the invention

[0006] Problem that the invention aims to solve

[0007] However, in the method described in patent document 1, since the irradiation direction of the particle beam is inclined relative to the bonding surface of the substrate, the dose of the particle beam incident on the substrate becomes uneven in the direction of the incident surface of the particle beam parallel to the substrate. In addition, as a particle beam source, it is linear, and sometimes the particle beam source used has a discharge chamber configured with the length direction of the discharge chamber parallel to the bonding surface of the substrate. However, in the case of such a particle beam source, the plasma density generated in the discharge chamber becomes uneven in the length direction of the discharge chamber, and with this, the dose of the particle beam in the direction orthogonal to the incident surface of the particle beam on the bonding surface of the substrate becomes uneven. Therefore, if the dose of the particle beam incident on the bonding surface of the substrate in the direction parallel to the incident surface of the particle beam in the bonding surface of the substrate and in the direction orthogonal to the incident surface becomes uneven, there is a risk that the entire bonding surface cannot be uniformly activated.

[0008] The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a joining device and a joining method capable of uniformly activating the entire joining surface of the objects to be joined.

[0009] Means to solve problems

[0010] In order to achieve the above-mentioned object, the bonding device of the present invention is:

[0011] A joining device for joining two objects to be joined, comprising:

[0012] a first object holding portion for holding any one of the two objects to be joined;

[0013] a second object holding portion, which is arranged to face the first object holding portion and to hold the other object of the two objects; and

[0014] A particle beam source radiates a particle beam to a region of a portion of any one of the bonding surfaces of the two objects to be bonded, wherein the particle beam source

[0015] The device has a plurality of radiation ports arranged along the direction of the bonding surface of the bonded object irradiated with the particle beam,

[0016] The opening area of ​​each of the plurality of radiation ports is set so that the radiation port arranged at a position farther from the center in the arrangement direction of the plurality of radiation ports has a larger opening area.

[0017] Effects of the Invention

[0018] According to the present invention, a particle beam source has a plurality of radiation ports arranged in the direction of the bonding surface of the object to be bonded irradiated by the particle beam, and the opening area of ​​each of the plurality of radiation ports is set such that the radiation port arranged farther away from the central part of the arrangement direction of the plurality of radiation ports is larger. Thus, since the dose of the particle beams respectively irradiated from the plurality of radiation ports is uniform, the particle beam can be uniformly irradiated in the arrangement direction of the plurality of radiation ports on the bonding surface of the object to be bonded. In addition, while irradiating the particle beam from the particle beam source to the object to be bonded, the particle beam is moved in a direction horizontal to the bonding surface of the object to be bonded, thereby uniformly irradiating the particle beam in the moving direction of the particle beam source on the bonding surface of the object to be bonded. Therefore, the entire bonding surface of the object to be bonded can be uniformly activated. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 This is a schematic front view of a bonding device according to an embodiment of the present invention.

[0020] Figure 2 A diagram showing a portion of a bonding apparatus according to an embodiment.

[0021] Figure 3 A schematic front view of a discharge chamber according to an embodiment.

[0022] Figure 4A A diagram showing a part of the bonding apparatus according to the embodiment, showing a state in which the distance between the stage and the head portion is the shortest.

[0023] Figure 4B A diagram showing a part of the bonding apparatus according to the embodiment, showing a state in which the distance between the stage and the head is the longest.

[0024] Figure 5AA diagram showing an irradiation area of ​​a particle beam on a stage according to an embodiment.

[0025] Figure 5B A diagram showing an irradiation area of ​​a particle beam in a head portion according to an embodiment.

[0026] Figure 6 An operation explanation diagram of the bonding device according to the embodiment.

[0027] Figure 7 A schematic front view of a discharge chamber of Comparative Example 1.

[0028] Figure 8 Displays film thickness measurement points of the substrate used for evaluating the uniformity of the particle beam dose in the activation process.

[0029] Fig.9A The film thickness distribution of the SiO2 film before and after the activation treatment of Comparative Example 1 is shown. Figure 8 Graph of the film thickness distribution in the P-axis direction.

[0030] Fig. 9B The film thickness distribution of the SiO2 film before and after the activation treatment of Comparative Example 1 is shown. Figure 8 Graph of film thickness distribution in the Q-axis direction.

[0031] Fig. 10A The film thickness distribution of the SiO2 film before and after the activation treatment of Comparative Example 1 is shown. Figure 8 Graph of the film thickness distribution in the P-axis direction.

[0032] Fig. 10B The film thickness distribution of the SiO2 film before and after the activation treatment of Comparative Example 1 is shown. Figure 8 Graph of film thickness distribution in the Q-axis direction.

[0033] Fig.11A The film thickness distribution of the SiO2 film before and after the activation treatment of the embodiment is shown. Figure 8 Graph of the film thickness distribution in the P-axis direction.

[0034] Fig. 11B The film thickness distribution of the SiO2 film before and after the activation treatment of the embodiment is shown. Figure 8 Graph of film thickness distribution in the Q-axis direction.

[0035] Fig. 12A The film thickness distribution of the SiO2 film before and after the activation treatment of the embodiment is shown. Figure 8 Graph of the film thickness distribution in the P-axis direction.

[0036] Fig. 12BThe film thickness distribution of the SiO2 film before and after the activation treatment of the embodiment is shown. Figure 8 Graph of film thickness distribution in the Q-axis direction.

[0037] Fig.13A A diagram showing a portion of a bonding device according to Comparative Example 2.

[0038] Fig. 13B A diagram showing the distribution of the dose when the bonding apparatus according to Comparative Example 2 irradiates the substrate with a particle beam.

[0039] Fig.14 Schematic diagram of the distribution of plasma in the particle beam source of Comparative Examples 1 and 2 and the embodiment.

[0040] Fig.15 A diagram showing a portion of a bonding device according to a modified example.

[0041] Fig.16 Operational explanation diagram of a joining device according to a modified example.

[0042] Fig.17 A schematic front view of a discharge chamber according to a modified example. DETAILED DESCRIPTION

[0043] Hereinafter, the bonding apparatus according to the first embodiment of the present invention will be described with reference to the accompanying drawings. In the bonding apparatus according to the present embodiment, the bonding surfaces of two substrates are activated in a chamber in a reduced pressure atmosphere, and then the substrates are brought into contact with each other and pressurized to bond the two substrates. Here, as the substrate, for example, it is an object to be bonded composed of any one of a Si substrate, a glass substrate such as a SiO2 glass substrate, an oxide substrate (for example, a silicon oxide (SiO2) substrate, an aluminum oxide substrate (Al2O3) including a sapphire substrate, gallium oxide (Ga2O3), etc.), a nitride substrate (for example, silicon nitride (SiN), aluminum nitride (AlN), gallium nitride (GaN)), a GaAs substrate, a silicon carbide (SiC) substrate, a lithium tantalate (Lt: LiTaO3) substrate, a lithium neodymium oxide substrate (Ln: LiNbO3), a diamond substrate, etc. Alternatively, as the substrates W1 and W2, it is also possible to be a substrate having an electrode formed of a metal such as Au, Cu, Al, or Ti on the bonding surface. In addition, the substrates W1 and W2 are preferably circular substrates with a diameter of less than 6 inches when viewed from above. In the activation process, the bonding surfaces of the two substrates are irradiated with a particle beam to activate the bonding surfaces of the substrates. In addition, the substrates can be heated before the activation process, or they can be heated when the two substrates are brought into contact with each other and pressurized.

[0044] Regarding the bonding device of this embodiment, Figure 1As shown in FIG. 1 , the apparatus includes a chamber 120, a stage 141, a head 142, a stage driving unit 143, a head driving unit 144, substrate heating units 1411 and 1421, a position deviation measuring unit 150, and particle beam sources 161 and 162. In the following description, Figure 2 The ±Z direction is used as the vertical direction, and the XY direction is used as the horizontal direction. The chamber 120 is connected to the vacuum pump 121a through the exhaust pipe 121b and the exhaust valve 121c. When the exhaust valve 121c is set to an open state to activate the vacuum pump 121a, the gas in the chamber 120 is discharged to the outside of the chamber 120 through the exhaust pipe 121b, and the air pressure in the chamber 120 is reduced (decompressed). In addition, the air pressure in the chamber 120 can be set to 10 －5 Pa or less. In addition, by changing the opening and closing amount of the exhaust valve 121 c to adjust the exhaust amount, the gas pressure (vacuum degree) in the chamber 120 can be adjusted.

[0045] The stage 141 and the head 142 are arranged in the chamber 120 to face each other in the Z direction. The stage 141 is the first object holding portion that holds the substrate W1 on its upper surface, and the head 142 is the second object holding portion that holds the substrate W2 on its lower surface. In addition, the upper surface of the stage 141 and the lower surface of the head 142 may also be roughened, considering that the contact surfaces of the substrates W1 and W2 with the stage 141 and the head 142 are mirror surfaces and are difficult to peel off from the stage 141 and the head 142. The stage 141 and the head 142 respectively have holding mechanisms (not shown) for holding the substrates W1 and W2. The holding mechanism includes an electrostatic chuck, a mechanical clamp, and the like. In addition, the stage 141 has a shape with a segment 141a formed on the periphery. Next, in a state where the substrates W1 and W2 are placed on the stage 141 , the peripheral portions of the substrates W1 and W2 are arranged above the step portion 141 a .

[0046] The stage driving unit 143 can move the stage 141 in the XY directions and rotate it around the Z axis.

[0047] The head driving unit 144 includes: a lifting driving unit 1441 for lifting and lowering the head 142 as indicated by arrow AR1; an XY direction driving unit 1442 for moving the head 142 in the XY direction; and a rotation driving unit 1443 for rotating the head 142 in the rotation direction around the Z axis. In addition, the head driving unit 144 includes: a piezo actuator 1444 for adjusting the inclination of the head 142 relative to the stage 141; and a pressure sensor 1445 for measuring the pressure applied to the head 142. The XY direction driving unit 1442 and the rotation driving unit 1443 move the head 142 relative to the stage 141 in the X direction, the Y direction, and the rotation direction around the Z axis, thereby making it possible to align the substrate W1 held on the stage 141 with the substrate W2 held on the head 142. In addition, the stage driving unit 143 is not limited to the structure arranged vertically below the stage 141. For example, it can also be the following structure: a backup portion (not shown) that bears pressure is provided vertically below the stage 141, and the stage driving unit 143 is arranged on the outer periphery of the stage 141 to drive the stage 141 from the side of the stage 141.

[0048] The lifting drive unit 1441 moves the head 142 vertically downward, thereby bringing the head 142 closer to the stage 141. In addition, the lifting drive unit 1441 moves the head 142 vertically upward, thereby moving the head 142 away from the stage 141. Next, when the lifting drive unit 1441 causes a driving force in a direction approaching the stage 141 to act on the head 142 while the substrates W1 and W2 are in contact with each other, the substrate W2 is pressed against the substrate W1. In addition, the lifting drive unit 1441 is provided with a pressure sensor 1441a for measuring the driving force acting on the head 142 in a direction approaching the stage 141. The pressure acting on the joint of the substrates W1 and W2 when the substrate W2 is pressed against the substrate W1 by the lifting drive unit 1441 can be detected based on the measurement value of the pressure sensor 1441a. The pressure sensor 1441a has, for example, a piezoelectric element.

[0049] A plurality of groups of piezoelectric actuators 1444 and pressure sensors 1445 are arranged between the head 142 and the XY direction driving unit 1442. The pressure sensor 1445 is disposed between the upper end of the piezoelectric actuator 1444 and the lower side of the XY direction driving unit 1442. The piezoelectric actuator 1444 can be extended and retracted in the up-and-down direction, and the piezoelectric actuator 1444 can finely adjust the inclination of the head 142 around the X-axis and around the Y-axis and the position of the head 142 in the up-and-down direction by extending and retracting. In addition, the pressure sensor 1445 has, for example, a piezoelectric element, and measures the pressure applied at multiple locations on the lower surface of the head 142. Furthermore, the plurality of piezoelectric actuators 1444 are driven respectively so that the pressure applied measured by the plurality of pressure sensors 1445 is equal, thereby making it possible to make the substrates W1 and W2 contact each other while maintaining the lower surface of the head 142 parallel to the upper surface of the stage 141.

[0050] The substrate heating unit 1411, 1421 is a first bonding object heating unit having an electric heater located on the stage 141, the head 142, and embedded in the back side of the holding unit when viewed from the side of the surface with which the substrates W1, W2 abut. The substrate heating unit 1411, 1421 heats the substrates W1, W2 by transferring heat to the substrates W1, W2 supported by the stage 141, the head 142. In addition, by adjusting the heat generated by the substrate heating unit 1411, 1421, the temperature of the substrates W1, W2 or their bonding surfaces can be adjusted. The position deviation measuring unit 150 identifies the positions of the marks (alignment marks) for position alignment respectively provided on the substrates W1, W2, thereby measuring the horizontal position deviation of the substrate W1 relative to the substrate W2. The position deviation measuring unit 150 uses, for example, light (for example, infrared light) that passes through the substrates W1, W2 to identify the alignment marks of the substrates W1, W2. The stage driving unit 143 moves or rotates the stage 141 in the horizontal direction according to the positional deviation measured by the positional deviation measuring unit 150 , thereby performing a mutual positional alignment operation (alignment operation) of the substrates W1 and W2 .

[0051] The particle beam sources 161 and 162 are, for example, fast atom beam (FAB) sources, and are fixed to the stage 141 and the head 142 respectively through beam source support parts 122A and 122B. Here, the irradiation direction AR21 of the particle beam of the particle beam source 161 along the irradiation axis J1 is inclined relative to the perpendicular line n2 of the bonding surface of the substrate W2. In addition, the irradiation direction AR22 of the particle beam of the particle beam source 162 along the irradiation axis J2 is inclined relative to the perpendicular line n1 of the bonding surface of the substrate W1. The particle beam sources 161 and 162 are, for example, Figure 2As shown, there is a discharge chamber 1601, an electrode 1602 arranged in the discharge chamber 1601, a beam source driving unit (not shown), and a gas supply unit 1604 for supplying argon gas into the discharge chamber 1601. The discharge chamber 1601 is formed of a carbon material in a rectangular box shape, and a plurality of radiation ports 1601a, 1601b, and 1601c for emitting particle beams containing neutral atoms are provided on its peripheral wall.

[0052] Multiple radiation ports 1601a, 1601b, 1601c are as follows, for example Figure 3 As shown, the plurality of radiation ports 1601a, 1601b, 1601c are arranged in a row along the length direction of the discharge chamber 1601. Here, the arrangement direction of each radiation port 1601a, 1601b, 1601c is arranged to be parallel to the posture of the bonding surface of the substrates W1 and W2 irradiated by the particle beams emitted from the radiation ports 1601a, 1601b, 1601c. That is, the plurality of radiation ports 1601a, 1601b, 1601c are arranged in the direction along the bonding surface of the substrates W1 and W2 irradiated by the particle beams. In addition, the opening area of ​​each of the plurality of radiation ports 1601a, 1601b, 1601c is set so that the radiation ports 1601a, 1601b, 1601c arranged farther away from the arrangement direction of the plurality of radiation ports 1601a, 1601b, 1601c, that is, the central part of the length direction of the discharge chamber 1601, are larger. Compared with the opening diameter D1 of the plurality of radiation openings 1601a arranged in the region Po1, the opening diameter D2 of the plurality of radiation openings 1601b arranged in the region Po2 adjacent to the central portion of the region Po1 in the longitudinal direction of the discharge chamber 1601 is larger. In addition, compared with the opening diameter D2 of the plurality of radiation openings 1601c arranged in the region Po2, the opening diameter D3 of the plurality of radiation openings 1601c arranged in the region Po3 at both ends in the longitudinal direction of the discharge chamber 1601 is larger.

[0053] The beam source driving unit includes: a plasma generating unit (not shown) for generating plasma of argon gas in the discharge chamber 1601; and a DC power supply (not shown) for applying a DC voltage between the electrode 1602 and the peripheral wall of the discharge chamber 1601. The beam source driving unit applies a DC voltage between the peripheral wall of the discharge chamber 1601 and the electrode 1602 in a state where the plasma of argon gas is generated in the discharge chamber 1601. At this time, argon ions in the plasma are attracted to the peripheral wall of the discharge chamber 1601. At this time, when the argon ions heading toward the radiation port 1601a pass through the radiation port 1601a, they receive electrons from the peripheral wall of the discharge chamber 1601 formed of a carbon material at the outer peripheral portion of the radiation port 1601a. ​​Then, the argon ions become electrically neutralized argon atoms and are discharged outside the discharge chamber 1601. Here, the power supplied to the particle beam sources 161 and 162 is set to, for example, 1 kV and 100 mA. Next, the flow rate of the argon gas introduced into the discharge chamber 1601 by the particle beam sources 161 and 162 is set to, for example, 50 sccm. In addition, the density of the plasma containing argon generated in the discharge chamber 1601 at both ends of the discharge chamber 1601 in the longitudinal direction is smaller than the density in the central part of the discharge chamber 1601. In response to this, as described above, the plurality of radiation ports 1601a, 1601b, and 1601c of the discharge chamber 1601 are set such that the radiation ports 1601b and 1601c are arranged farther away from the central part (region Po1) in the longitudinal direction of the discharge chamber 1601, and the opening diameters D2 and D3 thereof are larger. Therefore, the dose of the particle beam irradiated from the particle beam source 161 to the regions P11 and P21 in the substrate W1 can be made uniform in the X-axis direction of the regions P11 and P21. Furthermore, the density of the particle beam irradiated from the particle beam source 161 to the regions P12 and P22 in the substrate W2 can be made uniform in the X-axis direction in the regions P12 and P22 .

[0054] Next, the operation of the bonding device according to this embodiment will be described. Figure 4A As shown, the particle beam source 161 irradiates the particle beam to the substrate W2 held by the head 142, and the particle beam source 162 irradiates the particle beam to the substrate W1 held by the stage 141. Here, the particle beam source 161 irradiates the particle beam to the area P12 on the -Y direction side of the substrate W2, and the particle beam source 162 irradiates the particle beam to the area P11 on the +Y direction side of the substrate W1. In this state, when the bonding device moves the head 142 away from the stage 141 as shown by the arrow AR11, the area of ​​the substrate W2 irradiated by the particle beam is Figure 5A As shown by the arrow AR21, it moves from the area P12 to the +Y direction. Figure 5B As shown by the arrow AR22, it moves from the area P11 to the -Y direction. Figure 4BAs shown, the particle beam source 161 irradiates the particle beam to the area P22 on the +Y direction side of the substrate W2, and the particle beam source 162 irradiates the particle beam to the area P21 on the -Y direction side of the substrate W1. Then, as shown by arrow A12, when the bonding device moves the head 142 in the direction close to the stage 141, the area irradiated by the particle beam in the substrate W2 moves from the area P22 to the -Y direction, and the area irradiated by the particle beam in the substrate W1 moves from the area P12 to the +Y direction. Then, it becomes Figure 4A The state shown. Here, the head 142 repeatedly rises and falls between a position separated from the stage 141 by a distance H1 and a position separated from the stage 141 by a distance H2. In addition, the distance H1 and the distance H2 are set to, for example, 1:3. Specifically, the distance H1 is set to 50 mm and the distance H2 is set to 150 mm. In addition, the head 142 is preferably raised and lowered to move from a state where the end edge of the region irradiated by the particle beam in the substrates W1 and W2 on the -Y direction side coincides with the end of the substrates W1 and W2 on the +Y direction side to a state where the end edge of the region irradiated by the particle beam in the substrates W1 and W2 on the +Y direction side coincides with the end edge of the substrates W1 and W2 on the -Y direction side.

[0055] In addition, the bonding device such as Figure 6 As shown, the moving speed of the head 142 is changed according to the distance between the stage 141 and the head 142. Specifically, when the distance between the stage 141 and the head 142 is relatively long and the density of the particle beam reaching the substrates W1 and W2 is relatively low, the moving speed of the head 142 is slow. On the other hand, when the distance between the stage 141 and the head 142 is relatively short and the density of the particle beam reaching the substrates W1 and W2 is relatively high, the moving speed of the head 142 is fast. Thereby, regardless of the position of the head 142 relative to the stage 141, since the amount of particle beam reaching the substrates W1 and W2 per unit time can be made uniform, the etching rate caused by the particle beam in the bonding surface of the substrates W1 and W2 can be made uniform.

[0056] Here, the evaluation results are described while comparing the uniformity of the particle beam dose on the bonding surfaces of the activated substrates W1 and W2 using the bonding apparatus of this embodiment with that of the bonding apparatus of Comparative Example 1. Figure 7As shown, there are particle beam sources 9161 and 9162 having a discharge chamber 91601, wherein the discharge chamber 91601 is formed of a carbon material into a rectangular box shape, and a plurality of radiation ports 91601a having the same opening diameter D1 for radiating particle beams are provided on its peripheral wall. In addition, regarding the bonding devices of Comparative Examples 1 and 2, only the particle beam sources 9161 and 9162 are different from the bonding devices regarding the embodiment, and the other structures and actions are the same as those of the bonding devices regarding the embodiment. Therefore, below, the structure of the bonding device regarding Comparative Example 1 is described using the same symbols as the symbols used for each structure of the bonding device regarding the embodiment. However, the bonding device regarding Comparative Example 1 is to raise and lower the head 142 at a fixed moving speed. In addition, in this evaluation, as substrates W1 and W2, substrates with a diameter of 4 inches on which a SiO2 film is formed by thermal oxidation treatment are used. Next, the film thickness distribution of the SiO2 film before and after the SiO2 film side of the substrate is activated by the particle beam sources 9161 and 9162 of the comparative example, and the film thickness distribution of the SiO2 film before and after the SiO2 film side of the substrate W1 and W2 is activated by the particle beam sources 161 and 162 of the embodiment are compared. Here, the SiO2 film side of the substrate W1 and W2 is held facing the particle beam sources 9161, 9162, 161, and 162 by the stage 141 and the head 142 of the bonding apparatus of the comparative example 1 and the embodiment, respectively. In addition, in the bonding apparatus of the comparative example 1, the head 142 is repeatedly raised and lowered 10 times at a moving speed of 3.5 mm / sec. In the bonding apparatus of the embodiment, the head 142 is repeatedly raised and lowered 10 times while the moving speed of the head 142 is changed between 3.5 mm / sec and 1.5 mmsec according to the distance between the stage 141 and the head 142.

[0057] The film thickness distribution of SiO2 film on substrates W1 and W2 is as follows Figure 8 As shown, the film thickness is measured in 13 regions P1 to P13 on substrates W1 and W2. In addition, the center positions of the regions P1 to P13 are respectively set to the coordinates shown in the following Table 1 when the P-axis coordinates and Q-axis coordinates of the centers of substrates W1 and W2 are set to 0 [mm].

[0058] [Table 1]

[0059] Measurement location P axis coordinate [mm] Q axis coordinate [mm] P1 0 0 P2 －15 0 P3 0 －15 P4 0 15 P5 15 0 P6 －40 0 P7 0 40 P8 0 －40 P9 40 0 P10 －15 －15 P11 －15 15 P12 15 －15 P13 15 15

[0060] In Comparative Example 1, the SiO2 film on the substrate W2 held by the head 142 was obtained before and after the activation treatment. Fig.9A and Fig. 9B The film thickness distribution shown in FIG. 1 is obtained for the SiO2 film on the substrate W1 held on the stage 141 before and after the activation treatment. Fig. 10A and Fig. 10BHere, the in-plane uniformity of the film thickness of the SiO2 film after the activation treatment of the substrate W2 held by the head 142 is 4.0%, and the in-plane uniformity of the film thickness of the SiO2 film after the activation treatment of the substrate W1 held by the stage 141 is 4.0%. In addition, the "in-plane uniformity" is equivalent to the ratio of the median of the film thickness of the SiO2 film in each of the regions P1 to P13 of the substrates W1 and W2 to the average of the film thickness of the SiO2 film in each of the regions P1 to P13.

[0061] In addition, in the embodiment, the SiO2 film of the substrate W2 held by the head 142 is obtained before and after the activation treatment. Fig.11A and Fig. 11B The film thickness distribution shown in FIG. 1 is obtained for the SiO2 film on the substrate W1 held on the stage 141 before and after the activation treatment. Fig. 12A and Fig. 12B The film thickness distribution is shown. Here, the in-plane uniformity of the film thickness of the SiO2 film of the substrate W2 held by the head 142 after the activation treatment is 1.2%, and the in-plane uniformity of the film thickness of the SiO2 film of the substrate W1 held by the stage 141 after the activation treatment is 1.1%. From the results of Comparative Example 1 and the embodiment, it is understood that: while changing the moving speed of the head 142 according to the distance between the stage 141 and the head 142, as with the particle beam sources 161 and 162 of the embodiment, if the plurality of radiation ports 1601a, 1601b, 1601c of the discharge chamber 1601 are set so that the opening diameters of the radiation ports 1601b and 1601c are larger as they are arranged at positions farther from the central part in the longitudinal direction of the discharge chamber 1601, the in-plane uniformity of the SiO2 films of the substrates W1 and W2 is improved. Here, it is understood that since the in-plane uniformity of the SiO2 film on the substrates W1 and W2 depends on the uniformity of the dose of the particle beam irradiated to the substrates W1 and W2, the particle beam sources 161 and 162 of the embodiment have improved uniformity of the dose of the particle beam irradiated to the surface of the substrates W1 and W2 compared with the particle beam sources 9161 and 9162 of Comparative Example 1. In other words, it is understood that in the embodiment, the uniformity of the dose of the particle beam irradiated to the surface of the substrates W1 and W2 has improved compared with Comparative Example 1.

[0062] By the way, if Fig.13AIn the previous bonding device shown in FIG. 1 , the positions of the particle beam sources 161 and 162 are fixed, and the particle beam is irradiated from the outside of the substrates W1 and W2 to the bonding surface of the substrates W1 and W2. In this configuration, the dose on the side of the substrates W1 and W2 close to the particle beam sources 161 and 162 becomes larger than the dose on the side away from the particle beam sources. Therefore, the etching amount on the side of the substrates W1 and W2 close to the particle beam sources 161 and 162 becomes larger than the etching amount on the side away from the particle beam sources, and a difference in etching amount occurs at both ends of the substrates W1 and W2 in the ±Y direction. In addition, as Fig. 13B As shown, in the case of the previous particle beam source 9161 having a rectangular box-shaped discharge chamber 91601, the density of the plasma generated in the discharge chamber 91601 at both ends of the discharge chamber 91601 in the longitudinal direction becomes smaller than the density of the central portion of the discharge chamber 91601 in the longitudinal direction. Therefore, in the case where the opening areas of the radiation ports 91601a arranged in a row along the longitudinal direction of the discharge chamber 91601 are equal, the dose of the particle beam emitted from the radiation ports 91601a arranged near the two ends in the longitudinal direction of the discharge chamber 91601 becomes smaller than the dose of the particle beam emitted from the radiation ports 91601a arranged near the central portion of the discharge chamber 91601. Therefore, a difference in the etching amount of the substrates W1 and W2 occurs between the central portion in the X-axis direction and the two ends in the X-axis direction of the substrates W1 and W2. Therefore, as Fig.14 As shown in FIG. 1 , uneven etching amounts occur in the X direction and the Y direction of each of the substrates W1 and W2 .

[0063] In this regard, in the bonding apparatus of the present embodiment, while the particle beam source 161 is fixed to the stage 141 and radiates the particle beam from the outside of the area where the substrate W1 is arranged in the stage 141 to the area including a part of the bonding surface of the substrate W2, the head driving unit 144 moves the head 142 in the ±Z direction. Thereby, as the head 142 moves in the ±Z direction, the area in the bonding surface of the substrate W2 irradiated by the particle beam moves within the bonding surface of the substrate W2. Therefore, by repeating the movement of the head 142 in the ±Z direction, the particle beam can be uniformly irradiated in the Y-axis direction of the substrate W2. In addition, the particle beam sources 161 and 162 of the present embodiment have a plurality of radiation ports 1601a, 1601b, and 1601c arranged in the direction of the bonding surface of the substrates W1 and W2 irradiated with the particle beam, and the opening area of ​​each of the plurality of radiation ports 1601a, 1601b, and 1601c is set such that the radiation port (for example, the radiation port 1601c) arranged farther away from the arrangement direction of the plurality of radiation ports 1601a, 1601b, and 1601c, that is, the central part in the length direction of the discharge chamber 1601, is larger. Thus, since the dose of the particle beams irradiated from the plurality of radiation ports 1601a, 1601b, and 1601c becomes uniform, the particle beams can be uniformly irradiated in the X-axis direction of the substrates W1 and W2. Therefore, the entire bonding surface of the substrates W1 and W2 can be uniformly activated.

[0064] Since the range in which the particle beam can be irradiated is limited to a certain extent in the bonding apparatus of this embodiment, it is particularly preferable to use substrates W1 and W2 of so-called small diameter substrates less than 4 inches.

[0065] In addition, regarding the bonding device of this embodiment, while the particle beam source 161 is fixed to the stage 141 and radiates the particle beam from the outside of the area where the substrate W1 is arranged in the stage 141 to the area including a part of the bonding surface of the substrate W2, the head driving unit 144 moves the head 142 in the ±Z direction. Thereby, as the head 142 moves in the ±Z direction, the area in the bonding surface of the substrate W2 irradiated by the particle beam moves within the bonding surface of the substrate W2. Therefore, by repeating the movement of the head 142 in the ±Z direction, the entire bonding surface of the substrate W2 can be uniformly irradiated with the particle beam, and the entire bonding surface can be uniformly activated. Next, since there is no need for a conveying mechanism for moving the particle beam source 161 in the horizontal direction relative to the substrate W2 while supporting the particle beam source 161, the entire device can be relatively miniaturized.

[0066] Although the embodiments of the present invention have been described above, the present invention is not limited to the configurations of the aforementioned embodiments. Fig.15 As shown, the particle beam sources 161 and 162 may not be fixed to the carrier 141 and the head 142 respectively. Fig.15 The same structure as the embodiment is the mark and Figure 2 The bonding device of this modified example includes a horizontal driving unit 3163 that supports the particle beam sources 161 and 162 together and moves the particle beam sources 161 and 162 in a horizontal direction perpendicular to the facing direction of the substrates W1 and W2. Fig.16 As shown in FIG. 1 , the particle beam sources 161 and 162 move as shown by arrow AR32 while irradiating the bonding surfaces of the substrates W1 and W2 with particle beams. Fig.17 The particle beam sources 2161 , 2162 of the discharge chamber 21601 are shown to replace the particle beam sources 161 , 162 .

[0067] In the bonding device described in the above-mentioned embodiment, when the particle beam is irradiated to the substrates W1 and W2, the dose of the particle beam irradiated to the substrates W1 and W2 will change due to the change in the distance between the particle beam 161 and 162 and the substrates W1 and W2, and the etching rate on the surface of the substrates W1 and W2 will change accordingly. In contrast, according to the present configuration, since the particle beam can be irradiated to the substrates W1 and W2 while the distance between the particle beam source 161 and 162 and the substrates W1 and W2 is maintained fixed, the moving speed of the particle beam 161 and 162 can be set to be fixed and the dose of the particle beam irradiated to the substrates W1 and W2 can be made uniform.

[0068] In an embodiment, for example Fig.17The particle beam sources 2161 and 2162 shown in the figure, the discharge chamber 21601 may also have a plurality of types of radiation ports 21601a, 21601b, and 21601c with different radiation directions. Here, the arrangement direction of the radiation ports 21601a, 21601b, and 21601c is configured to be parallel to the posture of the bonding surface of the substrates W1 and W2 irradiated by the particle beams emitted from the radiation ports 21601a, 21601b, and 21601c. That is, the plurality of radiation ports 21601a, 21601b, and 21601c are arranged in the direction along the bonding surface of the substrates W1 and W2 irradiated by the particle beams. In addition, the opening area of ​​each of the plurality of radiation ports 21601a, 21601b, 21601c is set such that the more the radiation ports 21601a, 21601b, 21601c are arranged in the arrangement direction of the plurality of radiation ports 21601a, 21601b, 21601c, that is, the central part in the longitudinal direction of the discharge chamber 21601, the larger the inclination angle from the direction perpendicular to the longitudinal direction of the discharge chamber 21601 to the side of one end in the longitudinal direction. Specifically, the radiation axis J21 of the particle beam of the plurality of radiation ports 21601a arranged in the area Po21 in the central part in the longitudinal direction of the discharge chamber 21601 is substantially parallel to the direction perpendicular to the longitudinal direction of the discharge chamber 21601. In addition, the radiation axes J22 of the plurality of radiation ports 21601b disposed in the region Po22 adjacent to the region Po21 in the longitudinal direction of the discharge chamber 21601 are inclined at an angle θ21 relative to the direction perpendicular to the longitudinal direction of the discharge chamber 21601, that is, relative to the radiation axis J21. Furthermore, the radiation axes J23 of the plurality of radiation ports 21601c disposed in the region Po23 at both ends in the longitudinal direction of the discharge chamber 21601 are inclined at an angle θ22 relative to the direction perpendicular to the longitudinal direction of the discharge chamber 21601, that is, relative to the radiation axis J21, and the angle θ22 is greater than the angle θ21.

[0069] In the particle beam sources 2161 and 2162 of this modified example, particle beams are radiated from the central portion of the length direction of the discharge chamber 21601 where the density of the plasma generated in the discharge chamber 21601 is relatively high, through the radiation ports 21601c disposed at both ends of the length direction of the discharge chamber 21601. Therefore, the difference in the dose of the particle beams radiated from the radiation ports 21601a, 21601b, and 21601c can be reduced. Thereby, the dose of the particle beams reaching the substrates W2 and W1 from the particle beam sources 2161 and 2162 can be made uniform in the X-axis direction in the regions P12, P22, P11, and P21 of the substrates W2 and W1 irradiated with the particle beams. Therefore, the etching rates of the substrates W1 and W2 can be made uniform in the Y-axis direction in the regions P11 and P21 of the substrate W1 and the regions P12 and P22 of the substrate W2.

[0070] In the embodiment, a radiation direction changing unit (not shown) for changing the radiation direction of the particle beam of at least one of the particle beam sources 161 and 162 may be provided according to the distance between the stage 141 and the head 142 .

[0071] In the embodiment, although an example is described in which two particle beam sources 161 and 162 are respectively fixed to the carrier 141 and the head 142, the present invention is not limited to this. For example, the bonding device may also have one particle beam source fixed to the carrier 141 and one particle beam source fixed to the head 142.

[0072] In the embodiment, although an example of raising and lowering the head 142 is described, the present invention is not limited thereto. For example, the stage 141 may be raised and lowered while the movement of the head 142 in the vertical direction is restricted, or both the stage 141 and the head 142 may be raised and lowered.

[0073] In the embodiment, in the activation treatment step, although an example of irradiating the bonding surface of the substrates W1 and W2 with a particle beam is described, it is not limited to this. For example, an ion gun can also be used to irradiate the bonding surface of the substrates W1 and W2 with an ion beam. In addition, in each embodiment, the particle beam sources 161 and 162 can also irradiate Si particles together with argon to the bonding surface of the substrates W1 and W2.

[0074] In each embodiment, although the examples in which the objects to be bonded are the substrates W1 and W2 are described, the present invention is not limited thereto, and for example, the objects to be bonded may be a wafer or a substrate.

[0075] The present invention considers various embodiments and modifications that do not deviate from the broad spirit and scope of the present invention as possible. In addition, the above-mentioned embodiments are used to illustrate this invention and are not used to limit the scope of the present invention. That is, the scope of the present invention is not represented by the embodiments, but by the claims. In addition, various modifications implemented within the scope of the claims and their equivalent inventions are considered to be within the scope of this invention.

[0076] This application is based on Japanese Patent Application No. 2022-100457 filed on June 22, 2022. The entire specification, claims, and drawings of Japanese Patent Application No. 2022-100457 are incorporated herein by reference.

[0077] Possibility of Industrial Application

[0078] The present invention is applicable to the manufacture of, for example, CMOS (Complementary MOS) image sensors, memories, computing elements, and MEMS (Micro Electro Mechanical Systems).

[0079] Explanation of symbols

[0080] 120: chamber, 121a: vacuum pump, 121b: exhaust pipe, 121c: exhaust valve, 122A, 122B: beam source support part, 141: stage, 142: head, 143: stage drive part, 144: head drive part, 150: position deviation measurement part, 161, 162, 2161, 2162: particle beam source, 1411, 1421: substrate heating part, 1441: lifting drive part, 1441a, 1445: pressure sensor, 1442: XY direction drive part, 1443: rotation drive part, 1444: piezoelectric actuator, 1601: discharge chamber, 1601a, 21601a: radiation port, 1602: electrode, J1, J2: irradiation axis, n1, n2: vertical line, W1, W2: substrate.

Claims

1. A joining device for joining two objects to be joined, comprising: A first object holding portion for holding any one of the two objects to be joined; a second object holding portion, which is arranged to face the first object holding portion and to hold the other object of the two objects; and a particle beam source for radiating a particle beam to a region including a portion of any one of the bonding surfaces of the two objects to be bonded, The aforementioned particle beam source The device has a plurality of radiation ports arranged in a direction along a bonding surface of an object to be bonded which is irradiated with a particle beam, The opening area of ​​each of the plurality of radiation ports is set so that the radiation port arranged at a position farther from the center in the arrangement direction of the plurality of radiation ports has a larger opening area.

2. A joining device for joining two objects to be joined, comprising: A first object holding portion for holding any one of the two objects to be joined; a second object holding portion, which is arranged to face the first object holding portion and to hold the other of the two objects to be joined; and a particle beam source for radiating a particle beam to a region including a portion of any one of the bonding surfaces of the two objects to be bonded, The aforementioned particle beam source The device has a plurality of radiation ports arranged along the direction of the bonding surface of the bonded object irradiated with the particle beam, The radiation direction of the particle beam of each of the plurality of radiation ports is set so that the radiation port arranged farther from the center in the arrangement direction of the plurality of radiation ports has a larger inclination angle from the direction perpendicular to the arrangement direction to one end side in the arrangement direction. 3 . The bonding device according to claim 1 , further comprising a horizontal drive unit for moving the particle beam source in a horizontal direction perpendicular to a facing direction of the two objects to be bonded.

4. A joining device for joining two objects to be joined, comprising: A first object holding portion for holding any one of the two objects to be joined; a second object holding portion, which is arranged to face the first object holding portion and to hold the other object of the two objects; a first particle beam source fixed to the first object holding portion and radiating a particle beam from outside a region of the first object holding portion where the one object is arranged to a region including a portion of a bonding surface of the other object; and The driving part moves at least one of the first object holding part and the second object holding part toward a first direction in which the first object holding part and the second object holding part approach each other or toward a second direction in which the first object holding part and the second object holding part separate from each other.

5. The joining device according to claim 4 further comprises: a second particle beam source, which is fixed to the aforementioned second object holding portion, and radiates a particle beam from the outside of the aforementioned other area of ​​the aforementioned second object holding portion to the area of ​​the aforementioned first object holding portion that includes a portion of the joining surface of the aforementioned one object to be joined.

6. The joining device according to claim 5, wherein The irradiation direction of the particle beam of the first particle beam source is inclined relative to the perpendicular line of the bonding surface of the other bonding object. The irradiation direction of the particle beam from the second particle beam source is inclined with respect to a perpendicular line of the bonding surface of the one of the objects to be bonded.

7. A joining device according to claim 5 or 6, wherein at least one of the first particle beam source and the second particle beam source has a plurality of radiation ports arranged in a row for radiating particle beams, and the arrangement direction of the plurality of radiation ports is arranged to be parallel to the posture of the joining surface of the two objects to be joined irradiated by the particle beams emitted from the radiation ports.

8. The bonding apparatus according to claim 5 or 6, wherein at least one of the first particle beam source and the second particle beam source The device has a plurality of radiation ports arranged along the direction of the bonding surface of the bonded object irradiated with the particle beam, The opening area of ​​each of the plurality of radiation ports is set so that the radiation port arranged at a position farther from the center in the arrangement direction of the plurality of radiation ports has a larger opening area.

9. The bonding apparatus according to claim 5 or 6, wherein at least one of the first particle beam source and the second particle beam source The device has a plurality of radiation ports arranged along the direction of the bonding surface of the bonded object irradiated with the particle beam, The radiation direction of the particle beam of each of the plurality of radiation ports is set so that the radiation port arranged farther from the center in the arrangement direction of the plurality of radiation ports has a larger inclination angle from the direction perpendicular to the arrangement direction to one end side in the arrangement direction.

10. The joining device according to any one of claims 4 to 9, wherein the driving portion moves at least one of the first object holding portion and the second object holding portion, so that the longer the distance between the first object holding portion and the second object holding portion, the slower the moving speed becomes.

11. The bonding apparatus according to any one of claims 1 to 10, wherein at least one of the two objects to be bonded is a circular substrate having a diameter of 6 inches or less in plan view.

12. A joining method, which is a joining method for joining two objects to be joined, comprising: a step of holding a portion to be joined, wherein any one of the two objects to be joined is held on a first object holding portion, and the other of the two objects to be joined is held on a second object holding portion arranged to face the first object holding portion; and an activation step of irradiating a particle beam from the particle beam source to a region including a portion of any one of the bonding surfaces of the two objects to be bonded, thereby activating the bonding surface; The aforementioned particle beam source The device has a plurality of radiation ports arranged along the direction of the bonding surface of the bonded object irradiated with the particle beam, The opening area of ​​each of the plurality of radiation ports is set so that the radiation port arranged at a position farther from the center in the arrangement direction of the plurality of radiation ports has a larger opening area.

13. A joining method, which is a joining method for joining two objects to be joined, comprising: a step of holding a portion to be joined, wherein any one of the two objects to be joined is held on a first object holding portion, and the other of the two objects to be joined is held on a second object holding portion arranged to face the first object holding portion; and an activation step of irradiating a particle beam from the particle beam source to a region including a portion of any one of the bonding surfaces of the two objects to be bonded, thereby activating the bonding surface; The aforementioned particle beam source The device has a plurality of radiation ports arranged along the direction of the bonding surface of the bonded object irradiated with the particle beam, The radiation direction of the particle beam of each of the plurality of radiation ports is set so that the radiation port arranged farther from the center in the arrangement direction of the plurality of radiation ports has a larger inclination angle from the direction perpendicular to the arrangement direction to one end side in the arrangement direction.

14. A bonding method, comprising: An activation step, wherein a first particle beam source fixed to the first object holding portion radiates a particle beam from the outside of an area of ​​the first object holding portion where the one object is arranged toward an area of ​​the second object holding portion including a portion of a bonding surface of the other object, while maintaining any one of the two objects to be bonded on the first object holding portion and maintaining the other of the two objects to be bonded on the second object holding portion arranged to face the first object holding portion, and at the same time, at least one of the first object holding portion and the second object holding portion moves in a first direction where the first object holding portion and the second object holding portion approach each other or in a second direction where the first object holding portion and the second object holding portion separate, thereby activating the bonding surfaces of the two objects to be bonded; and The joining step is to bring the joining surfaces of the two objects to be joined, whose joining surfaces have been activated, into contact with each other, thereby joining the two objects to be joined.

15. The joining method according to claim 14, wherein in the aforementioned joining step, while a second particle beam source fixed to the aforementioned second object holding portion radiates a particle beam from the outside of an area of ​​the aforementioned second object holding portion where the aforementioned other object is arranged to an area including a portion of the joining surface of the aforementioned one object, at the same time, at least one of the aforementioned first object holding portion and the aforementioned second object holding portion is moved in a first direction in which the aforementioned first object holding portion and the aforementioned second object holding portion approach each other or in a second direction in which the aforementioned first object holding portion and the aforementioned second object holding portion are separated.

16. The bonding method according to claim 14 or 15, wherein at least one of the two objects to be bonded is a circular substrate having a diameter of 6 inches or less in plan view.

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