WO2023249035A1

WO2023249035A1 - Joining device and joining method

Info

Publication number: WO2023249035A1
Application number: PCT/JP2023/022858
Authority: WO
Inventors: 朗山内; 朋義川崎
Original assignee: ボンドテック株式会社
Priority date: 2022-06-22
Filing date: 2023-06-21
Publication date: 2023-12-28

Abstract

This joining device comprises: a stage (141) that holds a substrate (W1); a head (142) that is arranged facing the stage (141) and that holds a substrate (W2); and particle beam sources (161, 162), each of which radiates a particle beam to a region including a section of a joining surface of the substrates (W1, W2). In addition, each of the particle beam source (161, 162) has a plurality of radiation ports that are arranged in a direction along the joining surface of the substrates (W1, W2) onto which the particle beam is radiated. An opening area of each of the plurality of radiation ports is set so as to be greater for a radiation port that is arranged at a position more distant from a longitudinal center section of a discharging chamber.

Description

Bonding equipment and bonding method

The present invention relates to a bonding device and a bonding method.

After performing a surface activation treatment that activates each bonding surface of a pair of substrates by irradiating the bonding surface of the pair of substrates with a particle beam, the bonding surfaces of the pair of substrates are brought into contact with each other. A method of joining has been proposed (for example, see Patent Document 1). In this method, a stage holding each of a pair of substrates is placed in a chamber at a distance from each other, and each substrate held on the stage is bonded from a particle beam source fixed at a fixed position in the chamber. The bonding surface of the substrate is activated by irradiating the surface with a particle beam.

JP 2015-8228 Publication

However, in the method described in Patent Document 1, since the irradiation direction of the particle beam is inclined with respect to the bonding surface of the substrate, the particle beam incident on the substrate is The dose amount becomes uneven. Further, as the particle beam source, a linear discharge chamber having a discharge chamber disposed in a posture such that its longitudinal direction is parallel to the bonding surface of the substrate may be employed. However, in the case of such a particle beam source, the plasma density generated in the discharge chamber becomes nonuniform in the longitudinal direction of the discharge chamber, and as a result, the plasma density generated in the discharge chamber becomes non-uniform in the longitudinal direction of the discharge chamber. The beam dose becomes non-uniform. In this way, if the dose of the particle beam incident on the bonding surface of the substrate becomes uneven in the direction parallel to the incident surface of the particle beam on the bonding surface of the substrate and in the direction orthogonal to the incident surface, it is difficult to uniformly spread the entire bonding surface. There is a possibility that it may not be activated.

The present invention has been made in view of the above reasons, and an object of the present invention is to provide a bonding apparatus and a bonding method that can uniformly activate the entire bonding surface of objects to be bonded.

In order to achieve the above object, the joining device according to the present invention includes:
A joining device for joining two objects to be joined,
a first workpiece holding section that holds one of the two workpieces;
a second workpiece holding part that is disposed opposite to the first workpiece holding part and holds the other workpiece of the two workpieces;
a particle beam source that emits a particle beam to a region including a part of the bonding surface of either of the two objects to be bonded;
The particle beam source includes:
It has a plurality of radiation ports arranged in a direction along the bonding surface of the object to be bonded to which the particle beam is irradiated,
The opening area of each of the plurality of radiation ports is set to be larger as the radiation ports are arranged farther from the center in the direction in which the plurality of radiation ports are arranged.

According to the present invention, the particle beam source has a plurality of radiation ports arranged in a direction along the bonding surface of the workpiece to be irradiated with the particle beam, and the opening area of each of the plurality of radiation ports has a plurality of opening areas. The radiation ports arranged at positions further away from the center in the direction in which the radiation ports are lined up are set larger. This makes the dose of the particle beam emitted from each of the plurality of radiation ports uniform, so that the particle beam can be irradiated uniformly in the direction in which the plurality of radiation ports are arranged on the bonding surface of the object to be joined. In addition, by moving the particle beam from the particle beam source toward the object to be welded and moving it in a direction horizontal to the surface to be welded, the direction of movement of the particle beam source on the surface to be welded The particle beam can be uniformly irradiated at Therefore, the entire bonding surface of the objects to be bonded can be activated uniformly.

1 is a schematic front view of a joining device according to an embodiment of the present invention. It is a figure showing a part of joining device concerning an embodiment. FIG. 2 is a schematic front view of a discharge chamber according to an embodiment. FIG. 2 is a diagram illustrating a part of the bonding apparatus according to the embodiment, and illustrating a state where the distance between the stage and the head is the shortest. FIG. 2 is a diagram showing a part of the bonding apparatus according to the embodiment, and showing a state where the distance between the stage and the head is the longest. FIG. 3 is a diagram showing a particle beam irradiation area on a stage according to an embodiment. FIG. 3 is a diagram showing a particle beam irradiation area in a head according to an embodiment. FIG. 3 is an explanatory diagram of the operation of the bonding device according to the embodiment. 3 is a schematic front view of a discharge chamber according to Comparative Example 1. FIG. FIG. 3 is a diagram showing the film thickness measurement locations on the substrate used to evaluate the uniformity of the dose of the particle beam in the activation process. 9 is a diagram showing the film thickness distribution of the SiO ₂ film before and after the activation treatment according to Comparative Example 1, and showing the film thickness distribution in the P-axis direction of FIG. 8. FIG. 9 is a diagram showing the film thickness distribution of the SiO ₂ film before and after the activation treatment according to Comparative Example 1, and showing the film thickness distribution in the Q-axis direction of FIG. 8. FIG. 9 is a diagram showing the film thickness distribution of the SiO ₂ film before and after the activation treatment according to Comparative Example 1, and showing the film thickness distribution in the P-axis direction of FIG. 8. FIG. 9 is a diagram showing the film thickness distribution of the SiO ₂ film before and after the activation treatment according to Comparative Example 1, and showing the film thickness distribution in the Q-axis direction of FIG. 8. FIG. 9 is a diagram showing the film thickness distribution of the SiO ₂ film before and after the activation treatment according to the embodiment, and showing the film thickness distribution in the P-axis direction of FIG. 8. FIG. 9 is a diagram showing the film thickness distribution of the SiO ₂ film before and after the activation treatment according to the embodiment, and showing the film thickness distribution in the Q-axis direction of FIG. 8. FIG. 9 is a diagram showing the film thickness distribution of the SiO ₂ film before and after the activation treatment according to the embodiment, and showing the film thickness distribution in the P-axis direction of FIG. 8. FIG. 9 is a diagram showing the film thickness distribution of the SiO ₂ film before and after the activation treatment according to the embodiment, and showing the film thickness distribution in the Q-axis direction of FIG. 8. FIG. 3 is a diagram illustrating a part of a bonding apparatus according to Comparative Example 2. FIG. 7 is a diagram showing a dose distribution when a substrate is irradiated with a particle beam using a bonding apparatus according to Comparative Example 2. FIG. FIG. 3 is a schematic diagram of plasma distribution in the particle beam sources according to Comparative Examples 1 and 2 and the embodiment. It is a figure showing a part of joining device concerning a modification. It is an explanatory diagram of operation of a joining device concerning a modification. It is a schematic front view of the discharge chamber based on a modification.

EMBODIMENT OF THE INVENTION Hereinafter, the joining apparatus based on Embodiment 1 of this invention is demonstrated with reference to figures. The bonding apparatus according to this embodiment performs an activation process on the bonding surfaces of two substrates in a chamber in a reduced pressure atmosphere, and then brings the two substrates into contact with each other and applies pressure. Join. Here, the substrate may be, for example, a glass substrate such as a Si substrate or a SiO ₂ glass substrate, an oxide substrate (for example, a silicon oxide (SiO ₂ ) substrate, an alumina substrate (Al ₂ O ₃ ) including a sapphire substrate, or a gallium oxide substrate). (Ga ₂ O ₃ ), nitride substrates (e.g. silicon nitride (SiN), aluminum nitride (AlN), gallium nitride (GaN)), GaAs substrates, silicon carbide (SiC) substrates, lithium tantalate (Lt: The bonded object is made of any one of a LiTaO ₃ ) substrate, a lithium niobate substrate (Ln:LiNbO ₃ ), a diamond substrate, and the like. Alternatively, the substrates W1 and W2 may be substrates whose bonding surfaces are provided with electrodes made of metal such as Au, Cu, Al, Ti, or the like. Further, it is preferable that the substrates W1 and W2 are each circular substrates having a diameter of 6 inches or less in a plan view. In the activation process, the bonding surfaces of the two substrates, which are to be bonded to each other, are irradiated with a particle beam to activate the bonding surfaces of the substrates. Note that the substrates may be heated before the activation treatment, or may be heated when the two substrates are brought into contact and pressurized.

As shown in FIG. 1, the bonding apparatus according to the present embodiment includes a chamber 120, a stage 141, a head 142, a stage drive section 143, a head drive section 144, substrate heating sections 1411 and 1421, and It includes a shift amount measuring section 150 and particle beam sources 161 and 162. In the following description, the ±Z direction in FIG. 2 will be described as the vertical direction, and the XY direction will be described as the horizontal direction. The chamber 120 is connected to a vacuum pump 121a via an exhaust pipe 121b and an exhaust valve 121c. When the exhaust valve 121c is opened and the vacuum pump 121a is operated, the gas inside the chamber 120 is exhausted to the outside of the chamber 120 through the exhaust pipe 121b, and the air pressure inside the chamber 120 is reduced (reduced pressure). Note that the atmospheric pressure inside the chamber 120 can be set to 10 ⁻⁵ Pa or less. Moreover, the air pressure (degree of vacuum) in the chamber 120 can be adjusted by varying the opening/closing amount of the exhaust valve 121c to adjust the exhaust amount.

The stage 141 and the head 142 are arranged in the chamber 120 so as to face each other in the Z direction. The stage 141 is a first object holder that holds the substrate W1 on its upper surface, and the head 142 is a second object holder that holds the substrate W2 on its lower surface. Note that the upper surface of the stage 141 and the lower surface of the head 142 are roughened, considering that the contact surfaces of the substrates W1 and W2 with the stage 141 and the head 142 are mirror-finished and difficult to peel off from the stage 141 and the head 142. may have been done. Stage 141 and head 142 each have a holding mechanism (not shown) that holds substrates W1 and W2. The holding mechanism includes an electrostatic chuck, a mechanical clamp, and the like. Further, the stage 141 has a shape in which a stepped portion 141a is formed around the periphery. Then, 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 141a.

The stage drive unit 143 can move the stage 141 in the XY directions or rotate it around the Z axis.

The head drive unit 144 includes an elevation drive unit 1441 that moves the head 142 up and down as shown by arrow AR1, an XY direction drive unit 1442 that moves the head 142 in the XY directions, and a rotation direction that rotates the head 142 around the Z axis. It has a rotation drive section 1443. The head drive unit 144 also includes a piezo actuator 1444 for adjusting the inclination of the head 142 with respect to the stage 141, and a pressure sensor 1445 for measuring the pressure applied to the head 142. The XY direction drive section 1442 and the rotation drive section 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 moving the substrate W1 held on the stage 141. This makes it possible to align the substrate W2 held by the head 142. Note that the stage drive section 143 is not limited to a configuration in which it is arranged vertically below the stage 141; for example, a backup section (not shown) that receives pressure is provided vertically below the stage 141, and the stage drive section 143 is arranged vertically below the stage 141. 143 may be arranged on the outer periphery of the stage 141, and the stage 141 may be driven from the side of the stage 141.

The elevating drive unit 1441 brings the head 142 closer to the stage 141 by moving the head 142 vertically downward. Further, the elevating drive unit 1441 moves the head 142 away from the stage 141 by moving the head 142 vertically upward. Then, when the elevating drive unit 1441 applies a driving force to the head 142 in a direction toward the stage 141 while the substrates W1 and W2 are in contact with each other, the substrate W2 is pressed against the substrate W1. Further, the elevating drive unit 1441 is provided with a pressure sensor 1441a that measures the driving force acting on the head 142 in a direction toward the stage 141. From the measured value by the pressure sensor 1441a, the pressure acting on the joint surface 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. The pressure sensor 1441a includes, for example, a piezoelectric element.

A plurality of pairs of piezo actuators 1444 and pressure sensors 1445 are arranged between the head 142 and the XY direction drive section 1442. The pressure sensor 1445 is interposed between the upper end of the piezo actuator 1444 and the lower side of the XY direction drive section 1442. The piezo actuators 1444 can be individually expanded and contracted in the vertical direction, and by expanding and contracting these, the inclination of the head 142 around the X-axis and the Y-axis and the vertical position of the head 142 are finely adjusted. Further, the pressure sensor 1445 includes, for example, a piezoelectric element, and measures the pressing force at a plurality of locations on the lower surface of the head 142. By driving each of the plurality of piezo actuators 1444 so that the pressing forces measured by the plurality of pressure sensors 1445 are equal, the lower surface of the head 142 and the upper surface of the stage 141 are maintained parallel to the substrates W1 and W2. can be brought into contact with each other.

For example, when the above-mentioned holding mechanism is an electrostatic chuck, the substrate heating units 1411 and 1421 include an electric heater embedded in the back side of the holding mechanism when viewed from the side of the stage 141 and the head 142 that contact the substrates W1 and W2. This is a first object heating section having a first object heating section. The substrate heating units 1411 and 1421 heat the substrates W1 and W2 by transmitting heat to the substrates W1 and W2 supported by the stage 141 and the head 142. Furthermore, by adjusting the amount of heat generated by the substrate heating units 1411 and 1421, the temperature of the substrates W1 and W2 or their bonding surfaces can be adjusted. The positional deviation measuring unit 150 measures the horizontal positional deviation of the substrate W1 with respect to the substrate W2 by recognizing the positions of alignment marks provided on each of the substrates W1 and W2. The positional deviation measurement unit 150 recognizes the alignment marks on the substrates W1 and W2 using, for example, light (eg, infrared light) that passes through the substrates W1 and W2. The stage driving section 143 performs an operation of aligning the substrates W1 and W2 with each other by moving or rotating the stage 141 in the horizontal direction based on the amount of positional deviation measured by the amount of positional deviation measuring section 150. (alignment operation).

The particle beam sources 161 and 162 are, for example, fast atom beam (FAB) sources, and are fixed to the stage 141 and head 142 via beam source supports 122A and 122B, respectively. Here, the irradiation direction AR21 of the particle beam of the particle beam source 161 along the irradiation axis J1 is inclined with respect to the perpendicular n2 to the bonding surface of the substrate W2. Further, the irradiation direction AR22 of the particle beam of the particle beam source 162 along the irradiation axis J2 is inclined with respect to the perpendicular n1 to the bonding surface of the substrate W1. As shown in FIG. 2, the particle beam sources 161 and 162 each include a discharge chamber 1601, an electrode 1602 disposed in the discharge chamber 1601, a beam source driver (not shown), and a discharge chamber that discharges argon gas. It has a gas supply section 1604 that supplies gas into the chamber 1601. The discharge chamber 1601 is formed from a carbon material in the shape of a long box, and its peripheral wall is provided with a plurality of radiation ports 1601a, 1601b, and 1601c that emit a particle beam containing neutral atoms.

The plurality of radiation ports 1601a, 1601b, and 1601c are each arranged in a row along the longitudinal direction of the discharge chamber 1601, as shown in FIG. 3, for example. Here, the radiation ports 1601a, 1601b, and 1601c are arranged in such a manner that the direction in which they are arranged is parallel to the joint surface of the substrates W1 and W2 to which the particle beams emitted from the radiation ports 1601a, 1601b, and 1601c are irradiated. . That is, the plurality of radiation ports 1601a, 1601b, and 1601c are arranged in a direction along the bonding surface of the substrates W1 and W2 to which the particle beam is irradiated. Further, the opening area of each of the plurality of radiation ports 1601a, 1601b, and 1601c is determined in the direction in which the plurality of radiation ports 1601a, 1601b, and 1601c are arranged, that is, the radiation located at a position away from the center in the longitudinal direction of the discharge chamber 1601. The openings 1601a, 1601b, and 1601c are set to be larger. The opening diameter D2 of the plurality of radiation ports 1601b arranged in the region Po2 adjacent to the region Po1 in the center in the longitudinal direction of the discharge chamber 1601 is equal to the opening diameter D1 of the plurality of radiation ports 1601a arranged in the region Po1. It's big in comparison. Further, the opening diameter D3 of the plurality of radiation ports 1601c arranged in the region Po3 at both ends in the longitudinal direction of the discharge chamber 1601 is larger than the opening diameter D2 of the plurality of radiation ports 1601c arranged in the region Po2. .

The beam source driver includes a plasma generator (not shown) that generates argon gas plasma in the discharge chamber 1601 and a DC power supply (not shown) that applies a DC voltage between the electrode 1602 and the peripheral wall of the discharge chamber 1601. ). The beam source driver applies a DC voltage between the peripheral wall of the discharge chamber 1601 and the electrode 1602 while generating argon gas plasma within 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 from a carbon material at the outer periphery of the radiation port 1601a. The argon ions then become electrically neutralized argon atoms and are emitted to the outside of 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. The flow rate of argon gas introduced into the discharge chamber 1601 of each of the particle beam sources 161 and 162 is set to, for example, 50 sccm. Furthermore, the density of the plasma containing argon generated in the discharge chamber 1601 is lower at both ends of the discharge chamber 1601 in the longitudinal direction than at the center of the discharge chamber 1601. On the other hand, the plurality of radiation ports 1601a, 1601b, and 1601c of the discharge chamber 1601 are, as described above, the radiation port 1601b arranged at a position away from the center (region Po1) in the longitudinal direction of the discharge chamber 1601, The aperture diameters D2 and D3 are set to be larger as the size becomes 1601c. Therefore, the dose of the particle beam irradiated from the particle beam source 161 onto the regions P11 and P21 on the substrate W1 can be made uniform in the X-axis direction in the regions P11 and P21. Further, the density of the particle beam irradiated from the particle beam source 161 onto the regions P12 and P22 on the substrate W2 can be made uniform in the X-axis direction in the regions P12 and P22.

Next, the operation of the bonding apparatus according to this embodiment will be explained. As shown in FIG. 4A, the particle beam source 161 irradiates the substrate W2 held by the head 142 with a particle beam, and the particle beam source 162 irradiates the substrate W1 held by the stage 141 with the particle beam. Here, the particle beam source 161 irradiates a region P12 on the −Y direction side of the substrate W2 with a particle beam, and the particle beam source 162 irradiates a region P11 on the +Y direction side of the substrate W1 with a particle beam. do. From this state, when the bonding apparatus moves the head 142 in the direction away from the stage 141 as shown by the arrow AR11, the area on the substrate W2 to which the particle beam is irradiated changes as shown by the arrow AR21 in FIG. 5A. Move in the +Y direction from area P12. Furthermore, the region on the substrate W1 that is irradiated with the particle beam moves from the region P11 in the −Y direction, as shown by the arrow AR22 in FIG. 5B. Then, as shown in FIG. 4B, the particle beam source 161 irradiates a region P22 on the +Y direction side of the substrate W2 with a particle beam, and the particle beam source 162 irradiates a region P21 on the -Y direction side of the substrate W1 with a particle beam. It will be in a state where it is irradiating. Next, when the bonding apparatus moves the head 142 in the direction approaching the stage 141 as shown by the arrow AR12, the region on the substrate W2 to which the particle beam is irradiated moves from the region P22 in the −Y direction, and the substrate The region irradiated with the particle beam in W1 moves in the +Y direction from region P12. Then, the state shown in FIG. 4A is reached again. Here, the head 142 repeatedly moves up and down between a position separated by a distance H1 from the stage 141 and a position separated by a distance H2 from the stage 141. Further, the distance H1 and the distance H2 are set to be, for example, 1:3. Specifically, the distance H1 is set to 50 mm and the distance H2 is set to 150 mm. Note that the head 142 moves from a state in which the -Y direction side edge of the region of the substrates W1, W2 to which the particle beam is irradiated coincides with the +Y direction side edge of the substrate W1, W2 to the +Y direction side edge thereof. It is preferable to move the substrates W1 and W2 up and down until they coincide with the edges of the substrates W1 and W2 in the -Y direction.

Further, as shown in FIG. 6, the bonding apparatus changes the moving speed of the head 142 depending on 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 beams reaching the substrates W1 and W2 is low, the moving speed of the head 142 is slowed down. On the other hand, when the distance between the stage 141 and the head 142 is relatively short and the density of the particle beams reaching the substrates W1 and W2 is high, the moving speed of the head 142 is increased. As a result, regardless of the position of the head 142 with respect to the stage 141, the amount of particle beams reaching the substrates W1 and W2 per unit time can be made uniform, so that the amount of particle beams reaching the substrates W1 and W2 can be made uniform. The etching rate can be made uniform.

Here, using the bonding apparatus according to the present embodiment, the uniformity of the dose of the particle beam to the bonding surfaces of the substrates W1 and W2 in the activation process was compared with that of the bonding apparatus according to Comparative Example 1. The results of the evaluation will be explained below. For example, as shown in FIG. 7, the bonding device according to Comparative Example 1 is formed of a carbon material into a long box shape, and has a peripheral wall thereof provided with a plurality of radiation ports 91601a having the same opening diameter D1 for emitting particle beams. The particle beam sources 9161 and 9162 are provided with a discharge chamber 91601 having a discharge chamber 91601. Note that the bonding apparatuses according to Comparative Examples 1 and 2 differ from the bonding apparatus according to the embodiment only in particle beam sources 9161 and 9162, and the other configurations and operations are similar to the bonding apparatus according to the embodiment. Therefore, the configuration of the bonding apparatus according to Comparative Example 1 will be described below using the same reference numerals as those used for each configuration of the bonding apparatus according to the embodiment. However, the bonding apparatus according to Comparative Example 1 moves the head 142 up and down at a constant moving speed. Further, in this evaluation, as the substrates W1 and W2, substrates having a diameter of 4 inches were used, in which a SiO ₂ film was formed on a Si substrate by thermal oxidation treatment. Then, the film thickness distribution of the SiO 2 film before and after the activation treatment of the SiO ₂ film side of the substrate using the particle beam sources 9161 and 9162 according to the comparative example, and the film thickness distribution of the SiO ₂ film using the particle beam sources 161 and 162 according to the embodiment are shown. The film thickness distributions of the SiO ₂ films before and after the activation treatment of the SiO ₂ film sides of the substrates W1 and W2 were compared. Here, the stage 141 and head 142 of the bonding apparatus according to Comparative Example 1 and the embodiment are arranged such that the SiO ₂ film side of the substrates W1 and W2 faces the particle beam sources 9161, 9162, 161, and 162. I let it hold. In addition, in the bonding apparatus according to Comparative Example 1, the head 142 was repeatedly raised and lowered 10 times at a moving speed of 3.5 mm/sec. In the bonding apparatus according to the embodiment, the head 142 was repeatedly raised and lowered 10 times while changing the moving speed between 3.5 mm/sec and 1.5 mm sec depending on the distance between the stage 141 and the head 142. .

The film thickness distribution of the SiO ₂ film on the substrates W1 and W2 was determined by measuring the film thickness in 13 regions P1 to P13 on the substrates W1 and W2, as shown in FIG. The center positions of each of the regions P1 to P13 were set to the coordinates shown in Table 1 below, assuming that the P-axis coordinates and Q-axis coordinates of the centers of the substrates W1 and W2 were respectively 0 [mm].

In Comparative Example 1, the SiO ₂ film on the substrate W2 held by the head 142 had a film thickness distribution as shown in FIGS. 9A and 9B before and after the activation process, and the SiO 2 film on the substrate W1 held on the stage 141 For the _two films, film thickness distributions as shown in FIGS. 10A and 10B were obtained before and after the activation treatment. Here, the in-plane uniformity of the film thickness of the SiO ₂ film on the substrate W2 held by the head 142 after the activation process is 4.0%, and the in-plane uniformity of the SiO ₂ film on the substrate W1 held on the stage 141 is 4.0%. The in-plane uniformity of the film thickness after the activation treatment was 4.0%. Note that "in-plane uniformity" corresponds to the ratio of the median film thickness of the SiO ₂ film in each of the regions P1 to P13 of the substrates W1 and W2 to the average value of the film thickness of the SiO ₂ film in each of the regions P1 to P13. .

Furthermore, in the embodiment, the SiO ₂ film on the substrate W2 held by the head 142 has a film thickness distribution as shown in FIGS. 11A and 11B before and after the activation process, and For the SiO ₂ film, film thickness distributions as shown in FIGS. 12A and 12B were obtained before and after the activation treatment. Here, the in-plane uniformity of the film thickness of the SiO ₂ film on the substrate W2 held by the head 142 after the activation process is 1.2%, and the in-plane uniformity of the SiO ₂ film on the substrate W1 held on the stage 141 is 1.2%. The in-plane uniformity of the film thickness after the activation treatment was 1.1%. From the results of Comparative Example 1 and the embodiment, the moving speed of the head 142 is changed depending on the distance between the stage 141 and the head 142, and like the particle beam sources 161 and 162 according to the embodiment, It is preferable that the plurality of radiation ports 1601a, 1601b, and 1601c of the discharge chamber 1601 are set such that the opening diameter becomes larger as the radiation ports 1601b and 1601c are disposed further away from the center in the longitudinal direction of the discharge chamber 1601. It can be seen that the in-plane uniformity of the SiO ₂ films on the substrates W1 and W2 is improved. Here, since the in-plane uniformity of the SiO ₂ film on the substrates W1 and W2 depends on the uniformity of the dose of the particle beam irradiated onto the substrates W1 and W2, the particle beam source 161 according to the embodiment, It can be seen that in comparison with the particle beam sources 9161 and 9162 according to Comparative Example 1, the particle beam source No. 162 has improved uniformity of the dose of the particle beam irradiated within the planes of the substrates W1 and W2. In other words, it can be seen that in the embodiment, the uniformity of the dose of the particle beam irradiated within the planes of the substrates W1 and W2 is improved compared to Comparative Example 1.

By the way, in the conventional bonding apparatus as shown in FIG. 13A, the positions of the particle beam sources 161 and 162 are fixed, and the particle beams are irradiated from the outside of the substrates W1 and W2 toward the bonding surface of the substrates W1 and W2. . In this configuration, the dose amount on the side of the substrates W1, W2 closer to the particle beam sources 161, 162 is larger than the dose amount on the side far from the particle beam source. Therefore, the amount of etching on the side of the substrates W1, W2 closer to the particle beam sources 161, 162 becomes larger than the amount of etching on the side far from the particle beam sources, and the amount of etching on the side of the substrates W1, W2 closer to the particle beam sources 161, 162 becomes larger than the amount of etching on the side far from the particle beam sources. This results in a difference in the amount of etching. Furthermore, as shown in FIG. 13B, when the conventional particle beam source 9161 has a discharge chamber 91601 in the shape of a long box, the plasma generated in the discharge chamber 91601 has a high density at the center in the longitudinal direction of the discharge chamber 1601. The density at both ends in the longitudinal direction is smaller than that of . Therefore, when the opening areas of the radiation ports 91601a provided in a row along the longitudinal direction of the discharge chamber 91601 are equal, particles are emitted from the radiation ports 91601a provided near both ends in the longitudinal direction of the discharge chamber 91601. The dose of the beam is smaller than the dose of the particle beam emitted from the radiation aperture 91601a provided near the center of the discharge chamber 91601. For this reason, a difference occurs in the amount of etching of the substrates W1, W2 between the central portion of the substrates W1, W2 in the X-axis direction and the end portions of the substrates W1, W2 in the X-axis direction. Therefore, as shown in FIG. 14, uneven etching occurs in the X and Y directions of the substrates W1 and W2, respectively.

On the other hand, in the bonding apparatus according to the present embodiment, the particle beam source 161 is fixed to the stage 141 and includes a part of the bonding surface of the substrate W2 from outside the region of the stage 141 where the substrate W1 is arranged. The head driving unit 144 moves the head 142 in the ±Z direction while emitting the particle beam to the region. Accordingly, as the head 142 moves in the ±Z direction, the region on the bonding surface of the substrate W2 that is irradiated with the particle beam moves within the bonding surface of the substrate W2. Therefore, by repeatedly moving the head 142 in the ±Z directions, it is possible to uniformly irradiate the substrate W2 with the particle beam in the Y-axis direction. Further, the particle beam sources 161 and 162 according to the present embodiment have a plurality of radiation ports 1601a, 1601b, and 1601c arranged in a direction along the bonding surface of the substrates W1 and W2 to which the particle beam is irradiated. Radiation ports (for example 1601c). This makes the dose of the particle beam emitted from each of the plurality of radiation ports 1601a, 1601b, and 1601c uniform, so that the substrates W1 and W2 can be uniformly irradiated with the particle beam in the X-axis direction. Therefore, the entire bonding surface of the substrates W1 and W2 can be activated uniformly.

The bonding apparatus according to the present embodiment is preferably applied to so-called small-diameter substrates in which the substrates W1 and W2 are less than 4 inches, since the range in which the particle beam can be irradiated is limited to some extent.

In addition, in the bonding apparatus according to the present embodiment, the particle beam source 161 is fixed to the stage 141, and the particle beam source 161 is directed from outside the area of the stage 141 where the substrate W1 is placed to an 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 while emitting the beam. Accordingly, as the head 142 moves in the ±Z direction, the region on the bonding surface of the substrate W2 that is irradiated with the particle beam moves within the bonding surface of the substrate W2. Therefore, by repeatedly moving the head 142 in the ±Z directions, 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. Further, since there is no need for a transport mechanism for supporting the particle beam source 161 and moving the particle beam source 161 in a direction horizontal to the substrate W2, the overall size of the apparatus can be reduced accordingly.

Although the embodiments of the present invention have been described above, the present invention is not limited to the configurations of each of the above-described embodiments. For example, as shown in FIG. 15, particle beam sources 161 and 162 may not be fixed to stage 141 and head 142, respectively. Note that in FIG. 15, the same components as in the embodiment are given the same reference numerals as in FIG. The bonding apparatus according to this modification includes a horizontal drive unit 3163 that collectively supports the particle beam sources 161 and 162 and moves the particle beam sources 161 and 162 in a horizontal direction perpendicular to the direction in which the substrates W1 and W2 face each other. In the bonding apparatus according to this modification, as shown in FIG. 16, the particle beam sources 161 and 162 move in the direction indicated by the arrow AR32 while irradiating the bonding surfaces of the substrates W1 and W2 with particle beams, respectively. . Note that the bonding apparatus according to this modification may include particle beam sources 2161 and 2162 having a discharge chamber 21601 shown in FIG. 17, which will be described later, instead of the particle beam sources 161 and 162.

In the bonding apparatus described in the above embodiment, the distance between the particle beams 161, 162 and the substrates W1, W2 changes during irradiation of the particle beams onto the substrates W1, W2. The dose of the particle beam irradiated to the substrate changes, and the etching rate of the surfaces of the substrates W1 and W2 changes accordingly. On the other hand, according to the present configuration, the particle beams can be irradiated onto the substrates W1 and W2 while maintaining a constant distance between the particle beam sources 161 and 162 and the substrates W1 and W2. While keeping the moving speeds of the particles 161 and 162 constant, the dose of the particle beam irradiated onto the substrates W1 and W2 can be made uniform.

In the embodiment, the discharge chamber 21601 may have a plurality of types of radiation ports 21601a, 21601b, and 21601c with different radiation directions, as in the particle beam sources 2161 and 2162 shown in FIG. 17, for example. Here, the radiation ports 21601a, 21601b, and 21601c are arranged in such a manner that the direction in which they are lined up is parallel to the joint surface of the substrates W1 and W2 to which the particle beams emitted from the radiation ports 21601a, 21601b, and 21601c are irradiated. . That is, the plurality of radiation ports 21601a, 21601b, and 21601c are arranged in a direction along the bonding surface of the substrates W1 and W2 to which the particle beam is irradiated. Further, the opening area of each of the plurality of radiation ports 21601a, 21601b, and 21601c is determined by the direction in which the plurality of radiation ports 21601a, 21601b, and 21601c are lined up, that is, the radiation arranged at a position away from the center in the longitudinal direction of the discharge chamber 21601. The openings 21601a, 21601b, and 21601c have a larger inclination angle from a direction perpendicular to the longitudinal direction of the discharge chamber 21601 toward one end in the longitudinal direction. Specifically, the radiation axis J21 of the particle beams of the plurality of radiation ports 21601a arranged in the central area Po21 in the longitudinal direction of the discharge chamber 21601 is approximately parallel to the direction orthogonal to the longitudinal direction of the discharge chamber 21601. be. Furthermore, the radiation axis J22 of the plurality of radiation ports 21601b arranged in the region Po22 adjacent to the region Po21 in the longitudinal direction of the discharge chamber 21601 is in a direction perpendicular to the longitudinal direction of the discharge chamber 21601, that is, with respect to the radiation axis J21. and is inclined by an angle θ21. Furthermore, the radiation axis J23 of the plurality of radiation ports 21601c arranged in the region Po23 at both longitudinal ends of the discharge chamber 21601 is at an angle with respect to the direction perpendicular to the longitudinal direction of the discharge chamber 21601, that is, with respect to the radiation axis J21. It is inclined by θ22, and the angle θ22 is larger than the angle θ21.

In the particle beam sources 2161 and 2162 according to this modification, the plasma generated in the discharge chamber 21601 has a relatively high density of plasma, starting from a place near the center in the longitudinal direction of the discharge chamber 21601, to both ends of the discharge chamber 21601 in the longitudinal direction. A particle beam is emitted through a radiation aperture 21601c disposed in the radiation port 21601c. Therefore, the difference in the dose of the particle beams emitted from the radiation ports 21601a, 21601b, and 21601c can be reduced. This makes the dose of the particle beams reaching the substrates W2, W1 from the particle beam sources 2161, 2162, respectively, uniform in the X-axis direction in the regions P12, P22, P11, P21 on the substrates W2, W1 where the particle beams are irradiated. It can be done. Therefore, the etching rates of the substrates W1 and W2 can be made uniform in the Y-axis direction of the regions P11 and P21 of the substrate W1 and the regions P12 and P22 of the substrate W2.

The embodiment includes a radiation direction changing unit (not shown) that changes the radiation direction of the particle beam of at least one of the particle beam sources 161 and 162 according to the distance between the stage 141 and the head 142. There may be.

In the embodiment, an example has been described in which the two particle beam sources 161 and 162 are fixed to the stage 141 and the head 142, respectively, but the present invention is not limited to this. For example, the bonding device may be fixed to the stage 141. It may include one particle beam source fixed to the head 142, or it may include one particle beam source fixed to the head 142.

In the embodiment, an example has been described in which the head 142 is raised and lowered, but the present invention is not limited to this. 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 move up and down.

In the embodiment, an example has been described in which the bonding surface of the substrates W1 and W2 is irradiated with a particle beam in the activation process, but the invention is not limited to this. For example, an ion gun is used to irradiate the ion beam onto the substrates W1 and W2. It is also possible to irradiate the joint surface of W2. Further, in each embodiment, the particle beam sources 161 and 162 may irradiate the joint surface of the substrates W1 and W2 with Si particles together with argon.

In each embodiment, an example in which the objects to be bonded are the substrates W1 and W2 has been described, but the present invention is not limited to this, and for example, the objects to be bonded may be a chip and a substrate.

The present invention is capable of various embodiments and modifications without departing from the broad spirit and scope of the present invention. Moreover, the embodiments described above are for explaining the present invention, and do not limit the scope of the present invention. That is, the scope of the present invention is indicated by the claims rather than the embodiments. Various modifications made within the scope of the claims and within the meaning of the invention equivalent thereto are considered to be within the scope of this invention.

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.

The present invention is suitable for manufacturing, for example, CMOS (Complementary MOS) image sensors, memories, arithmetic elements, and MEMS (Micro Electro Mechanical Systems).

120: chamber, 121a: vacuum pump, 121b: exhaust pipe, 121c: exhaust valve, 122A, 122B: beam source support section, 141: stage, 142: head, 143: stage drive section, 144: head drive section, 150: Positional deviation measurement unit, 161, 162, 2161, 2162: Particle beam source, 1411, 1421: Substrate heating unit, 1441: Lifting drive unit, 1441a, 1445: Pressure sensor, 1442: XY direction drive unit, 1443: Rotation drive part, 1444: Piezo actuator, 1601: Discharge chamber, 1601a, 21601a: Radiation port, 1602: Electrode, J1, J2: Irradiation axis, n1, n2: Perpendicular line, W1, W2: Substrate

Claims

A joining device for joining two objects to be joined,
a first workpiece holding section that holds one of the two workpieces;
a second workpiece holding part that is disposed opposite to the first workpiece holding part and holds the other workpiece of the two workpieces;
a particle beam source that emits a particle beam to a region including a part of the bonding surface of either of the two objects to be bonded;
The particle beam source includes:
It has a plurality of radiation ports arranged in a direction along the bonding surface of the object to be bonded to which the particle beam is irradiated,
The opening area of each of the plurality of radiation ports is set to be larger as the radiation ports are arranged farther from the center in the direction in which the plurality of radiation ports are arranged.
Bonding equipment.
A joining device for joining two objects to be joined,
a first workpiece holding section that holds one of the two workpieces;
a second workpiece holding part that is disposed opposite to the first workpiece holding part and holds the other workpiece of the two workpieces;
a particle beam source that emits a particle beam to a region including a part of the bonding surface of either of the two objects to be bonded;
The particle beam source includes:
It has a plurality of radiation ports arranged in a direction along the bonding surface of the object to be bonded to which the particle beam is irradiated,
The emission direction of the particle beam of each of the plurality of radiation ports varies from a direction perpendicular to the direction of arrangement to one direction in the direction of arrangement of the radiation ports arranged at a position farther from the center in the direction of arrangement of the plurality of radiation ports. The angle of inclination toward the end side is set large,
Bonding equipment.
further comprising a horizontal drive unit that moves the particle beam source in a horizontal direction perpendicular to a direction in which the two objects to be welded face each other;
The joining device according to claim 1 or 2.
A joining device for joining two objects to be joined,
a first workpiece holding section that holds one of the two workpieces;
a second workpiece holding part that is disposed opposite to the first workpiece holding part and holds the other workpiece of the two workpieces;
A region that is fixed to the first workpiece holding section and includes a part of the joining surface of the other workpiece from outside the region of the first workpiece holding section where the one workpiece is arranged. a first particle beam source that emits a particle beam to
At least one of the first workpiece holding part and the second workpiece holding part is moved in the first direction in which the first workpiece holding part and the second workpiece holding part approach each other, or in the first direction. a drive unit that moves the first workpiece holding part and the second workpiece holding part in a second direction in which they are separated;
Bonding equipment.
The bonding surface of the one workpiece in the first workpiece holding part is fixed to the second workpiece holding part, and from the outside of the area where the other workpiece in the second workpiece holding part is arranged. further comprising a second particle beam source that emits a particle beam to a region containing the part;
The joining device according to claim 4.
The irradiation direction of the particle beam of the first particle beam source is inclined with respect to the perpendicular to the bonding surface of the other object to be bonded,
The irradiation direction of the particle beam of the second particle beam source is inclined with respect to the perpendicular to the bonding surface of the one object to be bonded.
The joining device according to claim 5.
At least one of the first particle beam source and the second particle beam source has a plurality of radiation apertures arranged in a row for emitting particle beams, and the direction in which the plurality of radiation apertures are arranged is in line with the direction of the two radiation apertures. The particle beam emitted from the radiation port is arranged in a posture parallel to the joining surface of the object to be welded, which is irradiated with the particle beam emitted from the radiation port.
The joining device according to claim 5 or 6.
At least one of the first particle beam source and the second particle beam source,
It has a plurality of radiation ports arranged in a direction along the bonding surface of the object to be bonded to which the particle beam is irradiated,
The opening area of each of the plurality of radiation ports is set to be larger as the radiation ports are arranged farther from the center in the direction in which the plurality of radiation ports are arranged.
The joining device according to claim 5 or 6.
At least one of the first particle beam source and the second particle beam source,
It has a plurality of radiation ports arranged in a direction along the bonding surface of the object to be bonded to which the particle beam is irradiated,
The emission direction of the particle beam of each of the plurality of radiation ports varies from a direction perpendicular to the direction of arrangement to one direction in the direction of arrangement of the radiation ports arranged at a position farther from the center in the direction of arrangement of the plurality of radiation ports. The angle of inclination toward the end side is set large,
The joining device according to claim 5 or 6.
The drive unit is configured to move the first workpiece holding part and the second workpiece holding part so that the moving speed becomes slower as the distance between the first workpiece holding part and the second workpiece holding part becomes longer. moving at least one side of the object holding section;
The joining device according to any one of claims 4 to 9.
At least one of the two objects to be bonded is a circular substrate in plan view with a diameter of 6 inches or less,
The joining device according to any one of claims 1 to 10.
A joining method for joining two objects to be joined, the method comprising:
A first workpiece holding section holds one of the two workpieces, and a second workpiece is disposed opposite to the first workpiece holding section. a workpiece holding step of causing the holding section to hold the other workpiece of the two workpieces;
an activation step of activating the bonding surface by emitting a particle beam from a particle beam source to a region including a part of the bonding surface of either of the two objects to be bonded;
The particle beam source includes:
It has a plurality of radiation ports arranged in a direction along the bonding surface of the object to be bonded to which the particle beam is irradiated,
The opening area of each of the plurality of radiation ports is set to be larger as the radiation ports are arranged farther from the center in the direction in which the plurality of radiation ports are arranged.
Joining method.
A joining method for joining two objects to be joined, the method comprising:
A first workpiece holding section holds one of the two workpieces, and a second workpiece is disposed opposite to the first workpiece holding section. a workpiece holding step of causing the holding section to hold the other workpiece of the two workpieces;
an activation step of activating the bonding surface by emitting a particle beam from a particle beam source to a region including a part of the bonding surface of either of the two objects to be bonded;
The particle beam source includes:
It has a plurality of radiation ports arranged in a direction along the bonding surface of the object to be bonded to which the particle beam is irradiated,
The emission direction of the particle beam of each of the plurality of radiation ports varies from a direction perpendicular to the direction of arrangement to one direction in the direction of arrangement of the radiation ports arranged at a position farther from the center in the direction of arrangement of the plurality of radiation ports. The angle of inclination toward the end side is set large,
Joining method.
One of the two objects to be welded is held by the first object holder, and the other of the two objects is held by the first object holder. A first particle beam source fixed to the first workpiece holding part is held by a second workpiece holding part disposed opposite to the first workpiece holding part. The first object to be welded is irradiated with a particle beam from outside the area where the one object to be welded is placed to a region of the second object holder that includes a part of the bonding surface of the other object to be welded. At least one of the bonded object holding section and the second bonded object holding section is moved in a first direction in which the first bonded object holding section and the second bonded object holding section approach each other or the first bonded object. an activation step of activating the bonding surfaces of the two objects to be bonded by moving the holding section and the second object holding section in a second direction where they separate;
a bonding step of bonding the two objects to be bonded by bringing the bonding surfaces of the two objects to be bonded whose bonding surfaces have been activated into contact with each other;
Joining method.
In the bonding step, a second particle beam source fixed to the second object holder is configured to beam the one object from outside the region of the second object holder where the other object is arranged. At least one of the first workpiece holding section and the second workpiece holding section is moved in the first direction or the second workpiece holding section while irradiating a particle beam onto a region including a part of the joining surface of the workpiece move in two directions,
The joining method according to claim 14.
At least one of the two objects to be bonded is a circular substrate in plan view with a diameter of 6 inches or less,
The joining method according to claim 14 or 15.