Cathode, high-speed atomic beam source, method for manufacturing a junction substrate, and method for regenerating a cathode

Abstract

To provide a technique capable of suppressing the release of particle deposits from a high speed atomic beam source and suppressing the reduction of the degree of vacuum in the high speed atomic beam source.SOLUTION: A cathode 100 has six inner surfaces in a high speed atomic beam source 500. The inner surfaces comprise six flat cathode members 103, and have an inert gas introduction port 102 to introduce inert gas into the cathode and a particle beam emission port 101 to emit high speed atomic beams to the outside of the cathode. The cathode members have, on planes thereof, a block body pasting area where a block body 300 is pasted. The block body pasting area is an area where a re-attachment amount of sputter dust caused by sputtering is larger than a removal amount of the cathode members by the sputtering caused by the use of the high speed atomic beam source. A volume ratio of a volume of the block body is 1-15% relative to an internal volume of the cathode, and a pasting area of an adhesive material is 25% or more on an adhesive surface of the inside of the cathode in the block body.SELECTED DRAWING: Figure 3

Description

Technical Field

[0001] The present invention relates to a cathode, a high-speed atomic beam source, a method for manufacturing a bonding substrate, and a method for regenerating a cathode.

Background Art

[0002] One of the techniques for bonding substrates is a room-temperature bonding technique using high-speed atomic beam irradiation. In this technique, an atomic beam is irradiated onto the bonding target surface of the substrate to be bonded to remove surface contamination and oxide films, and after exposing the dangling bonds, which are the bonding hands, to activate the surface, the bonding target surfaces of the substrates are overlapped and pressure-bonded at room temperature to bond the substrates together.

[0003] As the atomic beam source used for room-temperature bonding, a saddle-field type high-speed atomic beam source is used (see, for example, Patent Document 1). The saddle-field type high-speed atomic beam source supplies an inert gas such as argon (Ar) gas (hereinafter, argon gas will be exemplified for explanation) into a cathode housing having an anode inside, ionizes the inert gas atoms by applying a voltage between the anode and the cathode, and extracts an Ar atomic beam from an opening provided in a part of the cathode and irradiates the substrate. Since most of the Ar ions recombine with electrons on the way to the cathode to become a neutral Ar atomic beam and are irradiated, there is little electrostatic repulsion between Ar atoms, and it has the characteristic of being irradiated onto the substrate as a highly directional atomic beam.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0005] In the substrate bonding technology using the aforementioned fast atomic beam source (FAB gun), some of the particles generated within the fast atomic beam source, along with the Ar atomic beam, can fly out of the gun and adhere to the substrate, becoming a factor that inhibits bonding. Specifically, within the fast atomic beam source, some of the Ar atomic beam irradiates the cathode housing, causing a sputtering phenomenon. As a result, particles originating from the cathode housing fragments are generated, which become particles. Furthermore, on the inner surface of the cathode of the fast atomic beam source, the aforementioned sputtering phenomenon and the re-adhesion of particles generated by sputtering (hereinafter sometimes referred to as "redeposition") occur simultaneously. The particles accumulate at the corners of the cathode, forming aggregates that create particle deposits. As the thickness of these particle deposits increases, they become more prone to peeling and falling from the inner surface of the cathode, flying out of the fast atomic beam source and becoming a major factor in causing bonding interference when bonding substrates together. Furthermore, when processing the surface of a substrate to be bonded using a high-speed atomic beam source, the vacuum level inside the high-speed atomic beam source affects the efficiency of the surface treatment. Therefore, it is necessary to suppress particle emission and prevent a decrease in the vacuum level inside the high-speed atomic beam source.

[0006] Therefore, the present invention aims to provide a cathode, a high-speed atomic beam source, a method for manufacturing a junction substrate, and a method for regenerating a cathode that can suppress the emission of particle deposits from a high-speed atomic beam source and suppress the decrease in vacuum level within the high-speed atomic beam source. [Means for solving the problem]

[0007] The cathode of the present invention is a cathode for a high-speed atomic beam source, and the cathode has six inner surfaces and is a hollow box shape, the six inner surfaces comprising a bottom surface, an upper surface facing and parallel to the bottom surface, and four side surfaces connecting the bottom surface and the upper surface, the six inner surfaces being composed of six flat plate-shaped cathode members, the four side surfaces being parallel to each other when facing each other, and in one pair of two pairs of facing side surfaces of the four side surfaces, an inert gas inlet for introducing an inert gas into the cathode is provided on one side, and a particle beam emission port for emitting a high-speed atomic beam to the outside of the cathode is provided on the other side, the cathode part The material has a shape whose outline is formed by four corners and four sides connecting the corners, and on the plane of the cathode member constituting the inner surface of the cathode, there is a block body attachment area to which a block body is attached via an adhesive material, and the block body attachment area is an area in which the amount of sputter dust reattached by sputtering generated by the use of the high-speed atomic beam source is greater than the amount of the cathode member removed by sputtering, the volume of the block body is 1% to 15% of the volume of the inside of the cathode, and the adhesive surface of the block body to the inside of the cathode has an adhesive area of ​​25% or more.

[0008] In the cathode of the present invention, the block body attachment area may include the corner portion.

[0009] In the cathode of the present invention, the block body attachment region may further include the edges.

[0010] In the cathode of the present invention, the ratio (W1 / W0) of the shortest distance W1 between the two block bodies provided at the two corner portions connected by the first diagonal to the length W0 of the first diagonal, which is the diagonal connecting the two corner portions of the upper surface, may be 0.4 or more.

[0011] In the cathode of the present invention, on the side surface where the inert gas inlet and the particle beam outlet are not provided, the ratio (L1 / L0) of the shortest distance L1 between the two block bodies provided at the two corners connected by the second diagonal to the length L0 of the second diagonal, which is the diagonal connecting the two corners of the side surface, may be 0.5 or more.

[0012] In the cathode of the present invention, the ratio (H1 / H0) of the shortest distance H1 between the two block bodies provided at the two corners connected by the third diagonal to the length H0 of the third diagonal, which is the diagonal connecting the two corners of the side surface on which the inert gas inlet is provided, may be 0.5 or more.

[0013] In the cathode of the present invention, the exposed surface of the block body provided at the corner may be a surface that is recessed in a substantially hemispherical shape toward the corner.

[0014] In the cathode of the present invention, the block body may be made of graphite, glassy carbon, silicon, or silicon carbide.

[0015] In the cathode of the present invention, the cathode member may be made of graphite, glassy carbon, silicon, or silicon carbide.

[0016] The high-speed atomic beam source of the present invention comprises a cathode of the present invention and an anode provided inside the cathode.

[0017] The present invention relates to a method for manufacturing a bonded substrate, comprising: an irradiation step of irradiating the bonding target surface of the first semiconductor substrate and the bonding target surface of the second semiconductor substrate with a high-speed atomic beam in a vacuum using the high-speed atomic beam source of the present invention; and a contact step of bringing the bonding target surface of the first semiconductor substrate and the bonding target surface of the second semiconductor substrate, which have been irradiated with the high-speed atomic beam, into contact to obtain a laminate having a bonding interface.

[0018] The method for manufacturing a bonded substrate according to the present invention may further include a heat treatment step in which the laminate obtained in the bonding step is heat-treated to obtain a bonded substrate.

[0019] In the method for manufacturing a bonded substrate of the present invention, the first semiconductor substrate and the second semiconductor substrate may each be any of the following: a 3C-SiC single crystal substrate, a 4H-SiC single crystal substrate, a 6H-SiC single crystal substrate, or a SiC polycrystalline substrate.

[0020] In the method for manufacturing a bonded substrate of the present invention, the high-speed atomic beam may include argon, neon, or xenon.

[0021] The cathode regeneration method of the present invention includes a block body removal step of removing block bodies from the block body attachment area of ​​a cathode member constituting a cathode after use in a high-speed atomic beam source, and an attachment step of attaching new block bodies to the block body attachment area of ​​the cathode member from which the block bodies have been removed. [Effects of the Invention]

[0022] With the cathode of the present invention, by using the cathode of the present invention in a high-speed atomic beam source, the emission of particle deposits from the high-speed atomic beam source can be suppressed. Furthermore, the decrease in the vacuum level inside the high-speed atomic beam source is suppressed. As a result, the adhesion of particles to the bonding surface of the semiconductor substrate is suppressed, preventing bonding interference when bonding semiconductor substrates together, and also preventing a decrease in surface treatment efficiency due to a decrease in the vacuum level inside the high-speed atomic beam source, thereby improving the manufacturing efficiency of bonded substrates.

[0023] In the case of the high-speed atomic beam source of the present invention, since it includes the cathode of the present invention, it is possible to suppress the emission of particle deposits from the high-speed atomic beam source. In addition, it is possible to suppress a decrease in the degree of vacuum inside the high-speed atomic beam source. As a result, it is possible to suppress the adhesion of particles to the bonding target surface of the semiconductor substrate, suppress the occurrence of bonding inhibition when bonding semiconductor substrates, and suppress the decrease in the degree of vacuum inside the high-speed atomic beam source and the resulting decrease in the efficiency of surface treatment. Therefore, the manufacturing efficiency of the bonded substrate can be increased.

[0024] In the case of the method for manufacturing a bonded substrate of the present invention, since the bonding target surface of the substrate is irradiated using the high-speed atomic beam source including the cathode of the present invention, the emission of particle deposits from the high-speed atomic beam source is suppressed, and it is possible to suppress the adhesion of particles to the bonding target surface. In addition, it is possible to control a decrease in the degree of vacuum inside the high-speed atomic beam source. As a result, it is possible to suppress the occurrence of bonding inhibition when bonding substrates, improve the yield, and suppress the decrease in the efficiency of surface treatment of the semiconductor substrate, thereby increasing the manufacturing efficiency of the bonded substrate.

[0025] In the case of the method for regenerating the cathode of the present invention, the cathode after being used for a certain period of time can be regenerated into a state in which the emission of particle deposits can be suppressed again by a simple process and the decrease in the degree of vacuum inside the high-speed atomic beam source can be suppressed. Therefore, it is possible to suppress the emission of particle deposits from the high-speed atomic beam source and the decrease in the degree of vacuum inside the high-speed atomic beam source, increase the manufacturing efficiency of the bonded substrate, and extend the life of the cathode.

Brief Description of the Drawings

[0026] [Figure 1] It is a perspective view schematically showing a conventional high-speed atomic beam source. [Figure 2] It is a plan view schematically showing the state of the inner surface of the cathode member constituting the cathode after using a conventional high-speed atomic beam source. [Figure 3]This is a schematic perspective view showing the high-speed atomic beam source of this embodiment, which is used in Examples 1, 5, 9, 13, and Comparative Example 4, and a block body that is attached inside the cathode. [Figure 4] (A) is a plan view showing the top surface of the cathode in this embodiment, (B) is a cross-sectional view of the cathode in this embodiment parallel to the XY plane, and (C) and (D) are diagrams showing modified examples of the block body. [Figure 5] (A) is a plan view showing the side surface 150 of the cathode in this embodiment, (B) is a cross-sectional view of the cathode in this embodiment parallel to the YZ plane, and (C) is a cross-sectional view of the cathode in the YZ plane in a modified example. [Figure 6] (A) is a plan view showing the side surface 140 of the cathode in this embodiment, (B) is a cross-sectional view of the cathode in this embodiment parallel to the XZ plane, and (C) is a cross-sectional view of the cathode in the XZ plane in a modified example. [Figure 7] This is a schematic perspective view showing the high-speed atomic beam source used in Examples 2, 6, 10, and 14, and the block body attached to the inside of the cathode. [Figure 8] This is a schematic perspective view showing the high-speed atomic beam source used in Examples 3, 7, 11, and 15, and the block body attached to the inside of the cathode. [Figure 9] This is a schematic perspective view showing the high-speed atomic beam source used in Examples 4, 8, 12, and 16, and the block body attached to the inside of the cathode. [Figure 10] This is a schematic perspective view showing the high-speed atomic beam source used in Comparative Example 2 and the block body attached to the inside of the cathode. [Figure 11] This is a schematic perspective view showing the high-speed atomic beam source used in Comparative Example 3 and the block body attached to the inside of the cathode. [Figure 12] This figure illustrates a method for manufacturing a bonded substrate according to one embodiment of the present invention. [Figure 13]This diagram illustrates a method for regenerating a cathode according to one embodiment of the present invention. [Modes for carrying out the invention]

[0027] [High-speed atomic beam source, cathode, and cathode component] A fast atomic beam source, cathode, and cathode component according to one embodiment of the present invention will be described with reference to the drawings.

[0028] The high-speed atomic beam source of this embodiment is a saddle-field type high-speed atomic beam source that supplies an inert gas internally and emits a high-speed atomic beam of ionized inert gas to the outside from a particle beam emission port. Furthermore, the high-speed atomic beam source of this embodiment is used, for example, to perform surface treatment on the bonding surface of the substrate before the bonding process when manufacturing a bonded substrate by bonding two semiconductor substrates together. That is, it is used for the purpose of surface treatment in which the high-speed atomic beam emitted from the high-speed atomic beam source is irradiated onto the bonding surface of the substrate to be bonded, thereby activating the surface of the bonding surface.

[0029] Figure 1 shows a high-speed atomic beam source 800, which is an example of a conventional high-speed atomic beam source. The conventional high-speed atomic beam source 800 comprises a cathode 900 and an anode 200 provided inside the cathode 900. In this embodiment of the high-speed atomic beam source 800, cathode 900, and anode 200, the arrows X, Y, and Z in Figure 1 correspond to the width, depth, and height directions, respectively. The high-speed atomic beam source 800 is box-shaped, consisting of six plate-shaped cathode members 903, and comprises a bottom surface 910, an upper surface 920 opposite the bottom surface 910, and four side surfaces 930, 940, 950, and 960 connecting the bottom surface 910 and the upper surface 920. The bottom surface 910 and the upper surface 920, the side surfaces 930 and 940, and the side surfaces 950 and 960 are parallel to each other. Furthermore, a particle beam emission port 901 for emitting a high-speed atomic beam is formed on the side surface 930, and an inert gas inlet 902 for introducing an inert gas into the cathode 900 is provided on the side surface 940.

[0030] Figure 3 shows a high-speed atomic beam source 500 according to one embodiment of the present invention. It differs from the conventional high-speed atomic beam source 800 shown in Figure 1 in that a block body 300 is attached inside the cathode 100.

[0031] The high-speed atomic beam source 500 of this embodiment, shown in Figure 3, comprises a cathode 100 and an anode 200 provided inside the cathode 100. In the high-speed atomic beam source 500, cathode 100, and anode 200 of this embodiment, the directions of arrows X, Y, and Z in Figure 3 are the width direction, depth direction, and height direction, respectively.

[0032] The cathode 100 of this embodiment is a hollow box-shaped structure with six inner surfaces. For example, the cathode 100 is a rectangular parallelepiped with an inner width (w in Figure 3) of 56 mm, a depth (d in Figure 3) of 64 mm, and a height (h in Figure 3) of 102 mm. The six inner surfaces include a bottom surface 110, an upper surface 120 opposite the bottom surface 110, and four side surfaces 130, 140, 150, and 160 connecting the bottom surface 110 and the upper surface 120.

[0033] Furthermore, the bottom surface 110 and the top surface 120 are parallel to the XY plane, the sides 130 and 140 are opposite each other and parallel to the XZ plane, and the sides 150 and 160 are opposite each other and parallel to the YZ plane. In addition, these six inner surfaces are composed of six flat cathode members. In this embodiment, the cathode 100 is formed by assembling the six cathode members into a box shape.

[0034] Of the two opposing sets of sides (sides 130, 140 and sides 150, 160), sides 130 and 140 are provided with particle beam emission ports 101 and inert gas inlets 102. Specifically, side 130 is provided with particle beam emission ports 101 from which a high-speed atomic beam of ionized inert gas inside the cathode 100 is emitted. On side 140, which is opposite side 130 in the direction of arrow Y, is provided with an inert gas inlet 102 for introducing inert gas into the cathode 100. In this embodiment, the particle beam emission ports 101 consist of 64 circular through-holes with a diameter of 2 mm arranged at equal intervals in 8 rows in the height direction and 8 rows in the width direction, near the center of side 130. The inert gas inlet 102 consists of one circular through-hole with a diameter of 3 mm, located near the center of side 140. The shape, number, and location of the particle beam emission ports and inert gas inlets are not limited to this embodiment and may be in other configurations.

[0035] In this embodiment, two anodes 200 are provided inside the cathode 100 and are fixed inside the cathode 100 via an insulating member (not shown). The shape of the anodes 200 is cylindrical with a cross-sectional diameter of 10 mm and a height dimension approximately the same as the height of the cathode 100. The circular cross-section of the anodes 200 is parallel to the XY plane, and the central axis of the cylinder is parallel to the Z direction. As shown in Figure 4(A), the two anodes 200 are spaced apart from each other at the middle position in the depth direction of the cathode 100 (32 mm from the sides 130 and 140, respectively), such that the distance between the central axes of the two anodes 200 is 36 mm.

[0036] Furthermore, the anode material can be graphite, glassy carbon, silicon, silicon carbide, etc. In addition, tungsten, molybdenum, titanium, nickel, and their alloys and compounds can also be used.

[0037] Furthermore, the negative electrode of a DC current is connected to the cathode 100, and the positive electrode of a DC current is connected to the anode 200, and a high voltage of, for example, 0.5kV to 5kV is applied. This generates an electric field, causing the inert gas introduced into the cathode 100 from the inert gas inlet 102 to ionize, and a plasma is generated between the two anodes 200. In addition, the positive ions of the inert gas receive electrons from the cathode 100 and are emitted from the particle beam emission port 101 to the outside of the fast atomic beam source 500 as a fast atomic beam 510 (Figure 12). At this time, the flow of the inert gas is adjusted so that the irradiation current is, for example, about 10mA to 100mA.

[0038] Next, the cathode component will be explained with reference to the high-speed atomic beam source 500 shown in Figure 3.

[0039] The cathode member 103 is plate-shaped, with a contour formed by four corner portions 103a and four sides 103b connecting the corner portions 103a. Its thickness can be, for example, about 1 mm to 5 mm. Furthermore, on the plane of the cathode member that constitutes the inner surface of the cathode 100, there is a block body attachment area to which block bodies 300 are attached via adhesive material 400. In the cathode 100 of this embodiment, as shown in Figure 3, a triangular pyramidal first block body 301 is attached to the inside of the vertex of the cathode (the portion formed by the corner portions 103a of the cathode member 103), and triangular prism-shaped second block body 302, third block body 303, and fourth block body 304 are attached to the inside of the sides. Note that the through holes for the particle beam emission port 101 and the inert gas inlet 102 provided on the side surfaces 130 and 140 should not be blocked by the block bodies 300 or adhesive material 400.

[0040] Furthermore, the cathode material in this embodiment can be, for example, made of graphite, glassy carbon, silicon, or silicon carbide. In addition, tungsten, molybdenum, titanium, nickel, or their alloys and compounds can also be used.

[0041] Generally, when using the conventional high-speed atomic beam source 800 shown in Figure 1, the high-speed atomic beam is irradiated onto the inner surface of the cathode 900 (the surface of the cathode component), resulting in sputtering. This generates particles originating from fragments of the cathode 900 housing, which become part of the particle system. Furthermore, these particles may be emitted from the particle beam emission port 901 or reattach to and accumulate on the surface of the cathode component. In other words, in the cathode component constituting the cathode 900, sputtering and the reattachment of particles generated by sputtering to the surface of the cathode component occur simultaneously. As the thickness of this deposited layer of sputtering particles increases, it becomes more prone to peeling and falling from the inner surface of the cathode 900. These larger particles are emitted from the high-speed atomic beam source 800, becoming a major cause of bonding interference when joining substrates.

[0042] In the cathode member of this embodiment, the block body attachment region is a region where the amount of sputter dust reattached by sputtering is greater than the amount of cathode member removed by sputtering generated by the use of the high-speed atomic beam source 500 (i.e., it is a region that is easier to redeposition than sputtering). Furthermore, the volume of the block body 300 is the internal volume of the cathode 100 (i.e., in the cathode 100 of Figure 3, w × h × d = 352512 (mm²) 3The volume ratio of the block body is 1% to 15%. The volume ratio (%) of the block body can be calculated using the formula "Volume of block body / Volume inside cathode × 100 (%)". When calculating the volume ratio of the block body, it is assumed that the particle beam emission port 101 and inert gas inlet 102 provided on the sides 130 and 140 are flush and not have holes. If the volume ratio of the block body is too small, it becomes difficult to sufficiently suppress the emission of particle deposits. On the other hand, increasing the volume ratio of the block body tends to suppress particle deposition and the emission of particle deposits to the outside of the high-speed atomic beam source 500. In other words, if the volume ratio of the block body is too large, the influence on the electric field inside cathode 100 increases, reducing the emission efficiency of the high-speed atomic beam. This significantly reduces the efficiency of removing surface contamination and oxide films from the bonding surface of the semiconductor substrate, which can result in poor manufacturing efficiency.

[0043] Furthermore, Figure 4(A) is a plan view of the top surface 120 as seen from inside the cathode 100. In Figure 4(A), W0 and W1 are shown slightly offset for illustrative purposes, but both are on the diagonal. Similarly, in Figures 4(B), 5(A)(B), and 6(A)(B), W0, W2, L0, L1, L2, H0, H1, and H2 are also on the diagonal.

[0044] Considering the volume ratio of the block body 300 as described above, on the upper surface 120, the ratio (W1 / W0) of the shortest distance between the first block bodies 301 provided at the two corner portions 103a connected by the first diagonal 121 (the distance between the exposed surfaces 301a of the first block body 301 on the first diagonal 121) W1 to the length W0 of the first diagonal 121, which is the diagonal connecting the two corner portions 103a of the upper surface 120, may be 0.4 or more, and more preferably 0.5 or more. By setting W1 / W0 within an appropriate range, the release of particle deposits can be sufficiently suppressed.

[0045] Furthermore, Figure 4(B) is a cross-sectional view showing a cross-section 170 passing through the center P of the cathode, which is an example of a cross-section of the cathode 100 parallel to the XY plane. It is a cross-sectional view showing a cross-section 170 of the cathode 100 that is parallel to the XY plane and passes through the center P of the cathode. Considering the volume ratio of the block body 300 as described above, at the cross-section 170, the ratio (W2 / W0) of the shortest distance between the second block bodies 302 provided on the sides 103b connected by the diagonal 171 (the distance between the exposed surfaces 302a of the second block bodies 302 on the diagonal 171) W2 to the length W0 of the diagonal 171 connecting the sides 103b may be 0.4 or more, and more preferably 0.5 or more. By setting W2 / W0 within an appropriate range, the emission of particle deposits can be sufficiently suppressed. In this specification, if no block body is provided on side 103b in the cross-section of the cathode 100 parallel to the XY plane, W2 / W0 shall be considered as 1.0.

[0046] Figure 5(A) is a plan view of side surface 150 as seen from inside cathode 100. Considering the volume ratio of the block body 300 as described above, in side surface 150 where the inert gas inlet 102 and particle beam outlet 101 are not provided, the ratio (L1 / L0) of the shortest distance between the first block bodies 301 provided at the two corners 103a connected by the second diagonal 151 (the distance between the exposed surfaces 301a of the first block body 301 on the second diagonal 151) to the length L0 of the second diagonal 151, which is the diagonal connecting the two corners 103a of side surface 150, may be 0.5 or more, and more preferably 0.6 or more. By setting L1 / L0 within an appropriate range, the emission of particle deposits can be sufficiently suppressed.

[0047] Figure 5(B) is a cross-sectional view showing an example of a cross-section of a cathode 100 parallel to the YZ plane, specifically a cross-section 180 passing through the center P of the cathode. Considering the volume ratio of the block bodies 300 described above, at the cross-section 180, the ratio (L2 / L0) of the shortest distance between third block bodies 303 provided on the sides 103b connected by the diagonal 181 (the distance between the exposed surfaces 303a of the third block bodies 303 on the diagonal 181) L2 to the length L0 of the diagonal 181 connecting the sides 103b may be 0.5 or more, and more preferably 0.6 or more. By setting L2 / L0 within an appropriate range, the emission of particle deposits can be sufficiently suppressed. In this specification, if no block bodies are provided on the sides 103b in the cross-section of a cathode 100 parallel to the YZ plane, L2 / L0 shall be considered to be 1.0.

[0048] Figure 6(A) is a plan view of the side surface 140 as seen from inside the cathode 100. Considering the volume ratio of the block body 300 as described above, in the side surface 140 where the inert gas inlet is provided, the ratio (H1 / H0) of the shortest distance between the first block bodies 301 provided at the two corners 103a connected by the third diagonal 141 (the distance between the exposed surfaces 301a of the first block bodies 301 on the third diagonal 141) H1 to the length H0 of the third diagonal 141, which is the diagonal connecting the two corners 103a of the side surface 140, may be 0.5 or more, and more preferably 0.6 or more. By setting H1 / H0 within an appropriate range, the release of particle deposits can be sufficiently suppressed.

[0049] Figure 6(B) is a cross-sectional view showing a cross-section 190 passing through the center P of the cathode, which is an example of a cross-section of a cathode 100 parallel to the XZ plane. Considering the volume ratio of the block bodies 300 described above, at the cross-section 190, the ratio (H2 / H0) of the shortest distance between the fourth block bodies 304 provided on the sides 103b connected by the diagonal 191 (the distance between the exposed surfaces 304a of the fourth block bodies 304 on the diagonal 191) H2 to the length L0 of the diagonal 191 connecting the sides 103b may be 0.5 or more, and more preferably 0.6 or more. By setting H2 / H0 within an appropriate range, the emission of particle deposits can be sufficiently suppressed. In this specification, if no block bodies are provided on the sides 103b in the cross-section of a cathode 100 parallel to the YZ plane, H2 / H0 shall be considered to be 1.0.

[0050] Furthermore, the block body 300 in this embodiment can be made of, for example, graphite, glassy carbon, silicon, or silicon carbide, similar to the cathode member. In addition, tungsten, molybdenum, titanium, nickel, or their alloys and compounds can also be used.

[0051] Furthermore, the adhesive surface of the block body 300 against the inside of the cathode 100 is 25% or more. The adhesive surface is the ratio of the area to which the adhesive is applied to the total area of ​​the adhesive surface. This suppresses a decrease in the vacuum level inside the high-speed atomic beam source, thereby preventing a decrease in the efficiency of the surface treatment. The adhesive surface of the block body 300 against the inside of the cathode 100 is the surface to which the block body 300 is adhered to the inside of the cathode 100 via the adhesive 400. For example, in the case of the first block body 301A having four surfaces (Figure 4(c)), the remaining three surfaces, excluding the exposed surface 301A1, are attached to the inside of the cathode 100 via the adhesive 400, so these remaining three surfaces correspond to the adhesive surface. If the adhesive 400 is applied to the entire surface of this adhesive surface, the adhesive surface becomes 100%. However, the adhesive 400 only needs to be applied to the block body 300 so that it does not peel off from the inside of the cathode 100, and the adhesive 400 only needs to be applied to a part of the adhesive surface rather than the entire surface, so that the adhesive surface area of ​​the adhesive 400 is 25% or more. Examples of applying the adhesive to a part of the adhesive surface include applying the adhesive to the entire surface of one of the remaining three surfaces and leaving the other two surfaces without any adhesive, or applying the adhesive to a part of all three surfaces. Furthermore, the adhesive strength of the adhesive 400 must be such that the block body attached to the cathode member does not fall into the inside of the cathode 100. That is, the adhesive strength of the adhesive 400 on the surface on the block body 300 side and the surface on the flat side of the cathode member can be, for example, 5N / 25mm to 15N / 25mm.

[0052] Furthermore, the thickness of the adhesive 400 is not particularly limited, but can be, for example, about 50 μm to 300 μm.

[0053] In the cathode 100 of the high-speed atomic beam source 500, regions where the amount of particle re-deposition due to sputtering is greater than the amount of cathode material removed by sputtering generated by the use of the high-speed atomic beam source 500 are regions that are difficult to irradiate with the high-speed atomic beam. Therefore, by attaching the block body 300, the difficulty in irradiation with the high-speed atomic beam is eliminated, the shape of the inner surface of the cathode 100 becomes a shape that makes it difficult for particles to accumulate, and the difference between the amount of cathode material removed by sputtering and the amount of particle accumulation on the cathode material due to redeposition can be reduced. In other words, by attaching the block body, the shape inside the cathode that is prone to particle accumulation can be eliminated. As a result, by using the cathode 100 composed of the cathode material of this embodiment in the high-speed atomic beam source 500 and activating the bonding target surface of the semiconductor substrate to be bonded, the emission of large particle deposits from the high-speed atomic beam source can be suppressed. As a result, it is possible to suppress bonding inhibition when joining substrates together, and as mentioned above, to suppress the decrease in vacuum inside the high-speed atomic beam source that reduces the efficiency of surface treatment, thereby increasing the manufacturing efficiency of bonded substrates.

[0054] Here, Figure 2 is a schematic plan view showing the state of a side surface 930, which is an example of a cathode member that constitutes the cathode after use of a conventional high-speed atomic beam source. In Figure 2, the surface located on the inner side of the cathode is visible. The high-speed atomic beam source 800 (Figure 1) using the cathode member (side surface 930) shown in Figure 2 has the same configuration as the high-speed atomic beam source of this embodiment, except that there is no block body attachment area on the cathode member. When using the conventional high-speed atomic beam source 800, the inner part of the apex of the cathode (the part composed of the corner portion 903a of the cathode member) and the inner part of the edge of the cathode (the part composed of the edge 903b of the cathode member) are surrounded by the cathode member and are less likely to be irradiated by the high-speed atomic beam than other parts. As a result, the amount of deposition on the cathode member by redeposition is greater than the amount of cathode member removed by sputtering, and a deposition layer due to redeposition is likely to occur. In other words, as shown in Figure 2, particles generated by sputtering tend to reattach and accumulate in the region S near the contour of the cathode member, including the four corners 903a and edges 903b of the cathode member.

[0055] Therefore, as shown in Figure 3, it is preferable that the block body attachment region of the cathode member (the region to which the block body 300 is attached) includes the corner portion 103a of the cathode member. Furthermore, it is preferable that the block body attachment region further includes the edge portion 103b of the cathode member. By including the corner portion 103a and the edge portion 103b in the block body attachment region, it is possible to reduce the area where the amount of deposition by redeposition is greater than the amount of removal by sputtering, which is particularly difficult to irradiate with a high-speed atomic beam, thereby further suppressing particle deposition and more effectively suppressing the emission of particle deposits.

[0056] Furthermore, the shape of the block body 300 is preferably such that it follows the inner parts of the vertices and edges of the cathode 100 within the space inside the cathode 100, as shown in Figures 3 to 11. As such a block body 300, a triangular pyramid, a triangular prism, a cube, a rectangular prism, or other shapes can be used, and multiple block bodies of different shapes and sizes may be combined.

[0057] For example, in the cathode 100 of this embodiment shown in Figure 3, a block body 300 is formed by attaching a triangular pyramidal first block body 301, a triangular prism-shaped second block body 302, a triangular prism-shaped third block body 303, and a triangular prism-shaped fourth block body 304. The first block body 301 is shaped to follow the inner surface of the cathode corner formed at the corner portion of the cathode member, and three of its four faces are attached. The second block body 302, the third block body 303, and the fourth block body 304 are each shaped to follow the inner surface of their edges, and two of their five faces, which are rectangular, are attached.

[0058] Furthermore, Figure 4(C) is a plan view of the top surface 120 as seen from inside the cathode 100, and shows a high-speed atomic beam source 500A having a cathode 100 to which a modified block body 300A, which is a modified version of the block body 300, is attached. The dashed lines in Figure 4(C) indicate that, as will be described later, the exposed surface of the block body is concave toward the corner portion 103a and the edge 103b. As shown in Figure 4(C), the exposed surface 301A1 of the block body (first block body 301A) provided at the corner portion 103a has a surface that is concave in a substantially hemispherical shape toward the corner portion 103a, as indicated by the dashed lines. Thus, because the exposed surface 301A1 of the first block body 301A has a surface that is recessed in a substantially hemispherical shape toward the corner portion 103a, the boundary between the first block body 301A and the cathode member becomes smoother compared to the case where the first block body 301 without a recessed surface is attached, and the area that is difficult to irradiate with the high-speed atomic beam can be reduced. As a result, the difference between the amount of cathode member removed by sputtering and the amount deposited on the cathode member by redeposition can be reduced, thereby suppressing the deposition of particles originating from sputtering and further suppressing the emission of large particle deposits.

[0059] Furthermore, Figures 4(D), 5(C), and 6(C) are cross-sectional views of the cathode 100 parallel to the XY, YZ, and XZ planes, and show modified examples of the block body 300. As shown in Figures 4(C), 4(D), 5(C), and 6(C), the exposed surfaces 302A1, 303A1, and 304A1 of the block bodies (second block body 302A, third block body 303A, and fourth block body 304A) provided on side 103b have surfaces that are recessed in a substantially semi-cylindrical shape toward side 103b. In this way, by having the exposed surfaces of the block bodies recessed in a substantially semi-cylindrical shape toward side 103b, the boundary between the block body and the cathode member becomes smoother compared to the case where block bodies without recessed surfaces are attached, and the area that is difficult to irradiate with the high-speed atomic beam can be reduced. This reduces the difference between the amount of cathode material removed by sputtering and the amount deposited on the cathode material by redeposition, thereby suppressing the deposition of particles originating from sputtering and further suppressing the emission of large particle deposits.

[0060] [Method for manufacturing bonded substrates] Next, a method for manufacturing a bonded substrate according to one embodiment of the present invention will be described with reference to Figure 12. Figure 12(A) is a schematic diagram showing a bonding apparatus 600 irradiating the bonding target surfaces 711 and 721 of the first semiconductor substrate 710 and the second semiconductor substrate 720 with a high-speed atomic beam 510. Figure 12(B) is a schematic cross-sectional view showing the first semiconductor substrate 710' and the second semiconductor substrate 720' after the irradiation process. Figure 12(C) is a schematic cross-sectional view showing the laminate 700 obtained after the contact process.

[0061] The method for manufacturing a bonded substrate according to this embodiment is a method for manufacturing a bonded substrate in which a first semiconductor substrate 710 and a second semiconductor substrate 720 are laminated, and comprises: an irradiation step of irradiating the bonding target surface 711 of the first semiconductor substrate 710 and the bonding target surface 721 of the second semiconductor substrate 720 with a high-speed atomic beam 510 in a vacuum using the high-speed atomic beam source 500 of the embodiment described above; and a contact step of bringing the bonding target surface 711 of the first semiconductor substrate 710' and the bonding target surface 721 of the second semiconductor substrate 720', which have been irradiated with the high-speed atomic beam 510, into contact to obtain a laminate 700 having a bonding interface 730. Furthermore, the method for manufacturing a bonded substrate according to this embodiment may further comprise a heat treatment step of heat treating the laminate 700 obtained in the bonding step to obtain a bonded substrate.

[0062] The bonding apparatus 600 comprises a housing, two high-speed atomic beam sources 500, a vacuum pump (not shown) for creating a vacuum inside the housing, and holding means (not shown) for holding the first semiconductor substrate 710 and the second semiconductor substrate 720, and for moving the first semiconductor substrate 710 and the second semiconductor substrate 720 to predetermined positions in each manufacturing process. As shown in Figure 12, the two high-speed atomic beam sources 500 are installed to irradiate the bonding target surface 711 of the first semiconductor substrate 710 and the bonding target surface 721 of the second semiconductor substrate 720 with the high-speed atomic beams 510. In this embodiment, an embodiment in which the high-speed atomic beams 510 are irradiated onto the first semiconductor substrate 710 and the second semiconductor substrate 720 respectively is shown, but the irradiation of the high-speed atomic beams 510 only needs to be performed on at least one of the first semiconductor substrate 710 and the second semiconductor substrate 720.

[0063] The specific procedure will be explained with reference to Figure 12. The first semiconductor substrate 710 and the second semiconductor substrate 720 are placed in the bonding apparatus 600 so that the bonding target surface 711 of the first semiconductor substrate 710 and the bonding target surface 721 of the second semiconductor substrate 720 face each other, and the inside of the housing is evacuated, for example, 10 -4 Maintain a vacuum of approximately Pa or less.

[0064] First, an irradiation process is performed. As shown in Figure 12(A), the irradiation process involves irradiating the bonding target surface 711 of the first semiconductor substrate 710 and the bonding target surface 721 of the second semiconductor substrate 720 with a high-speed atomic beam 510 from a high-speed atomic beam source 500. As a result, the bonding target surfaces 711 and 721 are activated, and the first semiconductor substrate 710' and the second semiconductor substrate 720' are obtained.

[0065] Activation of bonding surfaces 711 and 721 refers to the removal of interface termination components such as oxygen, hydrogen, hydroxyl groups (OH groups), and oxide films from bonding surfaces 711 and 721 of the first semiconductor substrate 710 and the second semiconductor substrate 720, thereby forming a dangling bond.

[0066] Next, the contact process is performed. As shown in Figure 12(B), the first semiconductor substrate 710' and the second semiconductor substrate 720' are moved in the direction in which the bonding surfaces 711 and 721 approach each other (in the direction of the arrows in Figure 12(B)) until the bonding surfaces 711 and 721 come into contact. The inside of the housing 600 is pressurized to a predetermined pressure (for example, 100 kgf (0.98 kN)). The pressure is held for a predetermined time (for example, 3 minutes) to bond the first semiconductor substrate 710' and the second semiconductor substrate 720'. The contact process is then completed, and a laminate 700 (Figure 12(C)) having a bonding interface 730 is obtained.

[0067] Next, a heat treatment process is performed. By heat-treating the resulting laminate 700 inside the housing of the bonding apparatus 600 to, for example, about 300°C, a bonded substrate of the first semiconductor substrate 710 and the second semiconductor substrate 720 is obtained.

[0068] In the method for manufacturing a bonded substrate according to this embodiment, the first semiconductor substrate 710 and the second semiconductor substrate 720 can each be any of the following: a 3C-SiC single crystal substrate, a 4H-SiC single crystal substrate, a 6H-SiC single crystal substrate, or a SiC polycrystalline substrate.

[0069] Furthermore, the high-speed atomic beam 510 may contain argon, neon, or xenon.

[0070] According to the manufacturing method of the bonded substrate of this embodiment, the bonding target surfaces 711 and 721 of the first semiconductor substrate 710 and the second semiconductor substrate 720 are irradiated using a high-speed atomic beam source 500 equipped with a cathode 100. As a result, the emission of particle deposits from the high-speed atomic beam source 500 is suppressed, and the adhesion of particles to the bonding target surfaces 711 and 721 can be suppressed. In addition, the decrease in the vacuum level inside the high-speed atomic beam source 500 is suppressed. This suppresses bonding inhibition when bonding the first semiconductor substrate 710 and the second semiconductor substrate 720 together, thereby improving yield, and also suppresses a decrease in the efficiency of surface treatment of the semiconductor substrates, thereby increasing the manufacturing efficiency of the bonded substrate.

[0071] [How to regenerate the cathode] Next, a method for regenerating a cathode according to one embodiment of the present invention will be described with reference to Figure 13. In Figure 13, the cathode 100 of a high-speed atomic beam source 500 will be used as an example for explanation.

[0072] The cathode regeneration method of this embodiment is applied for the purpose of regenerating the cathode 100 of the embodiment described above. The cathode regeneration method of this embodiment includes a block body removal step (S1) of removing a block body 300' from the block body attachment area of ​​the cathode member constituting the cathode 100' after use in the high-speed atomic beam source 500, and an attachment step (S2) of attaching a new block body 300 to the block body attachment area of ​​the cathode member from which the block body 300' has been removed.

[0073] The specific procedure will be explained with reference to Figure 13. First, the anode 200 is removed from the high-speed atomic beam source 500 after use for a certain period of time. First, in the adhesive removal step (S1), the block bodies 300' (in this embodiment, the first block body 301', the second block body 302', the third block body 303', and the fourth block body 304') are removed from the cathode 100' to obtain a cathode member from which the adhesive has been removed. Next, in the attachment step (S2), new block bodies 300 of a predetermined shape (in this embodiment, the first block body 301, the second block body 302, the third block body 303, and the fourth block body 304) are reattached to the block body attachment area of ​​the cathode member. Note that the adhesive strength of the adhesive 400 decreases when the block bodies 300' are removed, so it is preferable to remove the adhesive 400 as well and use new adhesive 400 when attaching new block bodies 300.

[0074] In this way, the cathode after being used for a certain period of time can be regenerated, and a regenerated cathode 100 can be obtained.

[0075] In the cathode 100 of this embodiment, particle deposition is suppressed compared to conventional cathodes. However, after use for a certain period of time or longer, particles may accumulate in the block body attachment area of ​​the cathode 100, and these accumulated particles may detach and be released outside the high-speed atomic beam source 500. Therefore, with the cathode regeneration method of this embodiment, even if particles have accumulated on the cathode 100 after use for a certain period of time, the cathode 100 can be regenerated by a simple process to a state in which the release of particle deposits and the decrease in vacuum inside the high-speed atomic beam source are sufficiently suppressed. Thus, the release of particle deposits from the high-speed atomic beam source 500 is suppressed, improving the manufacturing efficiency of the bonded substrate, and eliminating the need to replace the entire cathode component due to particle deposition, thereby extending the lifespan of the cathode.

[0076] Furthermore, the present invention is not limited to the embodiments described above, and includes other processes and the like that can achieve the objectives of the present invention, as well as variations of the embodiments described above.

[0077] Furthermore, while the best configurations, methods, etc., for carrying out the present invention are disclosed in the above description, the present invention is not limited thereto. That is, although the present invention is described in particular with respect to specific embodiments, those skilled in the art can make various modifications to the embodiments described above in terms of shape, material, quantity, and other detailed configurations without departing from the scope of the technical idea and objectives of the present invention. Therefore, the descriptions of shapes, materials, etc. disclosed above are illustrative to facilitate understanding of the present invention and do not limit the present invention. Accordingly, descriptions of components with some or all of the limitations on shape, material, etc. removed are included in the present invention. [Examples]

[0078] The present invention will be described in more detail below with reference to examples and comparative examples, but the present invention is not limited in any way by these examples.

[0079] [Example 1] As the cathode, the cathode 100 (Figure 3) of the embodiment described above was used. Specifically, the cathode had a width of 56 mm, a height of 102 mm, and a depth of 64 mm, and the thickness of the cathode member was 3.2 mm. The cathode member and block body were made of graphite, and a block body 300 with the dimensions shown in Figure 3 was attached. The adhesive used had an adhesive strength of 10 N / 25 mm on both the surface attached to the cathode member and the surface exposed inside the cathode, and a thickness of 100 μm. The adhesive was applied to the entire contact surface between the block body 300 and the cathode member. At this time, the adhesive surface area on the adhesive surface of the block body to the inside of the cathode was 100%, meaning the adhesive was applied to the entire adhesive surface of the block body. In the cathode 100 of Example 1, the volume ratio (%) of the block body (volume of the block body / volume inside the cathode × 100 (%)) was 3.3%. Furthermore, the ratio (W / W0) of the shortest distance W (W1 or W2) between block bodies 300 (either the first block body 301 or the second block body 302) to the diagonal length W0 shown in Figures 4(A) and 4(B) was 0.73 to 0.92. Also, the ratio (L / L0) of the shortest distance L (L1 or L2) between block bodies 300 (either the first block body 301 or the third block body 303) to the diagonal length L0 shown in Figures 5(A) and 5(B) was 0.81 to 0.94. Furthermore, the ratio (H / H0) of the shortest distance H (H1 or H2) between block bodies 300 (either the first block body 301 or the fourth block body 304) to the diagonal length H0 shown in Figures 6(A) and 6(B) was 0.79 to 0.94. Table 2 shows the W / W0, L / L0, and H / H0 values ​​for each example and comparative example.

[0080] Furthermore, two cylindrical graphite anodes, each 10 mm in diameter and 100 mm in length, were used as anode 200. As shown in Figures 3 and 4, the two anodes 200 were fixed to the bottom surface 110 and top surface 120 of the cathode 100 via an insulating member, spaced apart from each other at the center of the depth direction of the cathode 100 (32 mm from the sides 130 and 140, respectively), so that the distance between the central axes of the two anodes 200 was 36 mm.

[0081] The inert gas was argon (Ar) gas, which was introduced into cathode 100 through the inert gas inlet. The acceleration voltage for irradiation with the fast atomic beam from the fast atomic beam source 500 was set to 1 kV, and the Ar gas flow was adjusted so that the irradiation current was 30 mA, and irradiation was performed. The first and second semiconductor substrates were silicon substrates with a diameter of 152 mm (6 inches) and a thickness of 625 μm.

[0082] Under the irradiation conditions described above, the high-speed atomic beam source 500 was first irradiated onto a silicon substrate for 300 seconds in its initial setup state, and then the number of particles on the silicon substrate was measured. This particle count was defined as the "initial particle count." The particle count was measured using a particle counter (model WM-7S, manufactured by TOPCON) with an edge exclusion of 5 mm and a minimum particle detection size of 0.15 μm.

[0083] Furthermore, it was anticipated that attaching a block to the cathode would reduce the emission efficiency of the high-speed atomic beam, thereby decreasing the efficiency of removing surface contamination and oxide films on the bonding surface of the semiconductor substrate. Therefore, to evaluate the efficiency of removing surface contamination and oxide films on the bonding surface, instead of using the semiconductor substrate used in the manufacture of the bonding substrate, the film thickness of a silicon thermal oxide film with a known thickness was measured before and after irradiation with a high-speed atomic beam. If the film thickness of the silicon thermal oxide film decreased after irradiation with a high-speed atomic beam, it could be considered that surface contamination and oxide films could be removed when surface treatment of the bonding surface of the semiconductor substrate was performed using that high-speed atomic beam source. The film thickness measurement was performed using an optical interferometry film thickness analyzer (Lambda Ace) manufactured by Dainippon Screen Co., Ltd.

[0084] The removal efficiency was evaluated in comparison with a high-speed atomic beam source that does not use block bodies (Comparative Example 1, described later), and the evaluation criteria were as follows. If the evaluation result was A, B, or C, the high-speed atomic beam source was evaluated as being applicable to the manufacture of bonded substrates. A: The film thickness change before and after irradiation is equivalent to the case without using a block body, and the removal efficiency is equivalent. B: Compared to cases where block bodies are not used, the reduction in film thickness after irradiation is slightly less, and a slight decrease in removal efficiency is observed, but the impact on manufacturing efficiency is negligible. C: Compared to cases where no block material is used, the reduction in film thickness after irradiation is smaller, and a decrease in removal efficiency is observed, but the impact on manufacturing efficiency due to the increased surface treatment time can be considered to be small. D: The reduction in removal efficiency is significant, and the surface treatment time becomes too long, resulting in an unacceptable impact on manufacturing efficiency.

[0085] Next, irradiation was performed intermittently in 30-minute intervals, alternating between irradiation and rest, until the cumulative usage time (cumulative value of irradiation time only) reached 20 hours. Then, the unused first and second semiconductor substrates were placed and irradiated with a high-speed atomic beam for 300 seconds. The number of particles on the first semiconductor substrate after 300 seconds of irradiation was measured and defined as the "number of particles after 20 hours of use." The increase ratio of the number of particles from the initial state (initial number of particles / number of particles after 20 hours of use) was then calculated. If this increase ratio was 10 times or less, it was evaluated that the emission of particle deposits was sufficiently suppressed, and the occurrence of major defects in bonding was extremely low. In the irradiation test of Example 1, the increase ratio of the number of particles was 2 times. In addition, the film thickness before and after 300 seconds of irradiation was measured, and the removal efficiency was evaluated to be equivalent to that without using block materials (evaluation A).

[0086] In addition to measuring the number of particles, the effect on the vacuum level inside the high-speed atomic beam source was evaluated. The evaluation was performed by comparing the vacuum levels of a high-speed atomic beam source with adhesive attached and a high-speed atomic beam source without adhesive (Comparative Example 1). The evaluation criteria for the effect on the vacuum level were set as follows, and it was judged that the decrease in vacuum level was suppressed if the result was A to C. As a result of the evaluation, the effect on the vacuum level in Example 1 was rated B. This is equivalent to not attaching block A, and there is no decrease in vacuum level. Compared to the case where block B was not attached, the vacuum level was slightly lower, but this did not affect manufacturing. Compared to the case where no C block was attached, the vacuum level decreased, but the desired vacuum level was reached by increasing the vacuuming time. Compared to cases where no block D material is attached, the vacuum level decreases, and even with longer vacuuming times, it is difficult to reach the required vacuum level. Although a product can be obtained, the efficiency of surface treatment is significantly poor, resulting in difficulties with productivity. The results are shown in Table 1.

[0087] Furthermore, a bonding substrate was manufactured by performing a contact process and a heat treatment process on a first semiconductor substrate and a second semiconductor substrate that had undergone an irradiation process using a high-speed atomic beam source after 20 hours of use. As a result, there was no damage to components such as the cathode member constituting the high-speed atomic beam source, and no bonding inhibition occurred in the bonding substrate, resulting in a properly bonded bonding substrate.

[0088] [Example 2] Next, Example 2 was performed. As the high-speed atomic beam source, a high-speed atomic beam source 500B (Figure 7) was used, in which a block body 300B having a triangular pyramidal block body 305 was attached to the corner of the cathode. The volume ratio of the block body was 1.0%, W / W0 was 0.76~1.0, L / L0 was 0.83~1.0, and H / H0 was 0.82~1.0. The irradiation test was performed in the same manner as in Example 1, except for the cathode. The increase ratio of the number of particles from the initial state was calculated to be 8.9 times. When the removal efficiency was evaluated, it was equivalent to that without using the block body (evaluation A). The effect on the vacuum level was evaluated as B. Furthermore, when the bonded substrate was manufactured, there was no damage to the cathode component or other components constituting the high-speed atomic beam source, and no bonding inhibition occurred in the bonded substrate, resulting in a normally bonded bonded substrate.

[0089] [Example 3] Next, Example 3 was performed. As the high-speed atomic beam source, a high-speed atomic beam source 500C (Figure 8) was used, in which block bodies 300C were attached to the corners and edges of the cathode. Block body 300C has triangular prism-shaped block bodies 307, 308, and 309 attached to the edges, and block body 306, which has four vertices cut off from a triangular pyramid to match the triangular faces of block bodies 307, 308, and 309. The volume ratio of the block bodies was 9.6%, W / W0 was 0.58 to 0.86, L / L0 was 0.70 to 0.90, and H / H0 was 0.68 to 0.90. The irradiation test was performed in the same manner as in Example 1, except for the cathode. The increase ratio of the number of particles from the initial state was calculated to be 2.9 times. When the removal efficiency was evaluated, a slight decrease in removal efficiency was observed, but the impact on the manufacturing efficiency was almost negligible (Evaluation B). Furthermore, the impact on the vacuum level was rated as B. In addition, as a result of manufacturing the bonded substrate, there was no damage to the cathode components and other parts constituting the high-speed atomic beam source, and no bonding inhibition occurred in the bonded substrate, resulting in a properly bonded substrate.

[0090] [Example 4] Next, Example 4 was performed. As a high-speed atomic beam source, a high-speed atomic beam source 500D (Figure 9) was used, in which block bodies 300D were attached to the corners and edges of the cathode. Block body 300D has triangular prism-shaped block bodies 311, 312, and 313 attached to the edges, and block body 310, which has four vertices cut off from a triangular pyramid to match the triangular faces of block bodies 311, 312, and 313. The volume ratio of the block bodies was 14.6%, W / W0 was 0.46 to 0.86, L / L0 was 0.61 to 0.90, and H / H0 was 0.59 to 0.90. The irradiation test was performed in the same manner as in Example 1, except for the cathode. The increase ratio of the number of particles from the initial state was calculated to be 1.9 times. When the removal efficiency was evaluated, a decrease in removal efficiency was observed, but the impact on manufacturing efficiency due to the increase in surface treatment time was considered to be small (evaluation C). The impact on the vacuum level was evaluated as B. Furthermore, as a result of manufacturing the bonded substrate, there was no damage to the cathode components and other parts constituting the high-speed atomic beam source, and no bonding inhibition occurred in the bonded substrate, resulting in a properly bonded substrate.

[0091] Next, Example 5 was performed. Example 5 was carried out in the same manner as Example 1, except that the adhesive surface area on the bonding surface to the inside of the cathode of the block body was set to 75%. As a result, the increase ratio of the particle number was 4.7%, the removal efficiency was rated A, and the effect on the vacuum level was rated A. Furthermore, as a result of manufacturing the bonded substrate, there was no damage to the cathode component or other components constituting the high-speed atomic beam source, and no bonding inhibition occurred in the bonded substrate, resulting in a bonded substrate that was properly bonded.

[0092] Next, Example 6 was performed. Example 6 was carried out in the same manner as Example 2, except that the adhesive surface area on the bonding surface to the inside of the cathode of the block body was set to 75%. As a result, the particle number increase ratio was 8.9%, the removal efficiency was rated A, and the effect on the vacuum level was rated B. Furthermore, as a result of manufacturing the bonded substrate, there was no damage to the cathode component or other components constituting the high-speed atomic beam source, and no bonding inhibition occurred in the bonded substrate, resulting in a bonded substrate that was properly bonded.

[0093] Next, Example 7 was performed. Example 7 was carried out in the same manner as Example 3, except that the adhesive surface area on the bonding surface to the inside of the cathode of the block body was set to 75%. As a result, the particle number increase ratio was 2.9%, the removal efficiency was rated B, and the effect on the vacuum level was rated B. Furthermore, as a result of manufacturing the bonded substrate, there was no damage to the cathode component or other components constituting the high-speed atomic beam source, and no bonding inhibition occurred in the bonded substrate, resulting in a bonded substrate that was properly bonded.

[0094] Next, Example 8 was performed. Example 8 was carried out in the same manner as Example 4, except that the adhesive surface area on the bonding surface to the inside of the cathode of the block body was set to 75%. As a result, the increase ratio of the particle number was 1.9%, the removal efficiency was rated C, and the effect on the vacuum level was rated B. Furthermore, as a result of manufacturing the bonded substrate, there was no damage to the cathode component or other components constituting the high-speed atomic beam source, and no bonding inhibition occurred in the bonded substrate, resulting in a bonded substrate that was properly bonded.

[0095] Next, Example 9 was performed. Example 9 was carried out in the same manner as Example 1, except that the adhesive application area on the bonding surface to the inside of the cathode of the block body was set to 50%. As a result, the particle number increase ratio was 4.7%, the removal efficiency was rated A, and the impact on the vacuum level was rated A. Furthermore, as a result of manufacturing the bonded substrate, there was no damage to the cathode component or other components constituting the high-speed atomic beam source, and no bonding inhibition occurred in the bonded substrate, resulting in a properly bonded substrate.

[0096] Next, Example 10 was performed. Example 10 was carried out in the same manner as Example 2, except that the adhesive surface area on the bonding surface to the inside of the cathode of the block body was set to 50%. As a result, the increase ratio of the particle number was 8.9%, the removal efficiency was rated A, and the impact on the vacuum level was rated A. Furthermore, as a result of manufacturing the bonded substrate, there was no damage to the cathode component or other components constituting the high-speed atomic beam source, and no bonding inhibition occurred in the bonded substrate, resulting in a bonded substrate that was properly bonded.

[0097] Next, Example 11 was performed. Example 11 was carried out in the same manner as Example 3, except that the adhesive application area on the bonding surface to the inside of the cathode of the block body was set to 50%. As a result, the particle number increase ratio was 2.9%, the removal efficiency was rated B, and the impact on the vacuum level was rated B. Furthermore, as a result of manufacturing the bonded substrate, there was no damage to the cathode component or other components constituting the high-speed atomic beam source, and no bonding inhibition occurred in the bonded substrate, resulting in a properly bonded substrate.

[0098] Next, Example 12 was performed. Example 12 was carried out in the same manner as Example 4, except that the adhesive surface area for bonding to the inside of the cathode of the block body was set to 50%. As a result, the increase ratio of the particle number was 1.9%, the removal efficiency was rated C, and the effect on the vacuum level was rated B. Furthermore, as a result of manufacturing the bonded substrate, there was no damage to the cathode component or other components constituting the high-speed atomic beam source, and no bonding inhibition occurred in the bonded substrate, resulting in a bonded substrate that was properly bonded.

[0099] Next, Example 13 was performed. Example 13 was carried out in the same manner as Example 1, except that the adhesive application area on the bonding surface to the inside of the cathode of the block body was set to 25%. As a result, the particle number increase ratio was 4.7%, the removal efficiency was rated A, and the impact on the vacuum level was rated A. Furthermore, as a result of manufacturing the bonded substrate, there was no damage to the cathode component or other components constituting the high-speed atomic beam source, and no bonding inhibition occurred in the bonded substrate, resulting in a properly bonded substrate.

[0100] Next, Example 14 was performed. Example 14 was carried out in the same manner as Example 2, except that the adhesive application area on the bonding surface to the inside of the cathode of the block body was set to 25%. As a result, the particle number increase ratio was 8.9%, the removal efficiency was rated A, and the impact on the vacuum level was rated A. Furthermore, as a result of manufacturing the bonded substrate, there was no damage to the cathode component or other components constituting the high-speed atomic beam source, and no bonding inhibition occurred in the bonded substrate, resulting in a properly bonded substrate.

[0101] Next, Example 15 was performed. Example 15 was carried out in the same manner as Example 3, except that the adhesive application area on the bonding surface to the inside of the cathode of the block body was set to 25%. As a result, the particle number increase ratio was 2.9%, the removal efficiency was rated B, and the effect on the vacuum level was rated A. Furthermore, as a result of manufacturing the bonded substrate, there was no damage to the cathode component or other components constituting the high-speed atomic beam source, and no bonding inhibition occurred in the bonded substrate, resulting in a properly bonded substrate.

[0102] Next, Example 16 was performed. Example 16 was carried out in the same manner as Example 4, except that the adhesive application area on the bonding surface to the inside of the cathode of the block body was set to 25%. As a result, the increase ratio of the particle number was 1.9%, the removal efficiency was rated C, and the impact on the vacuum level was rated A. Furthermore, as a result of manufacturing the bonded substrate, there was no damage to the cathode component or other components constituting the high-speed atomic beam source, and no bonding inhibition occurred in the bonded substrate, resulting in a properly bonded substrate.

[0103] [Comparative Example 1] Next, Comparative Example 1 was performed. The irradiation test was carried out in the same manner as in Example 1, except that a high-speed atomic beam source without a block attached to the cathode was used as the high-speed atomic beam source. The increase ratio of the number of particles from the initial state was calculated to be 20 times. Furthermore, when the bonded substrate was manufactured, although there was no damage to the cathode component and other components constituting the high-speed atomic beam source, bonding inhibition occurred in the substrate, and fracture locations were confirmed in the obtained bonded substrate.

[0104] [Comparative Example 2] Next, Comparative Example 2 was performed. As the high-speed atomic beam source, a high-speed atomic beam source 500E (Figure 10) was used, in which a block body 300E was attached to the corner of the cathode. The block body 300E has a triangular pyramidal block body 314. The volume ratio of the block body was 0.4%, W / W0 was 0.83~1.0, L / L0 was 0.88~1.0, and H / H0 was 0.87~1.0. The irradiation test was performed in the same manner as in Example 1, except for the cathode. The increase ratio of the number of particles from the initial state was calculated to be 12 times. When the removal efficiency was evaluated, it was equivalent to that without using the block body (evaluation A). The effect on the vacuum level was also evaluated as A. Furthermore, when the bonded substrate was manufactured, although there was no damage to the cathode component and other components constituting the high-speed atomic beam source, bonding inhibition occurred in the substrate, and fracture locations were confirmed in the obtained bonded substrate.

[0105] [Comparative Example 3] Next, Comparative Example 3 was performed. As the high-speed atomic beam source, a high-speed atomic beam source 500F (Figure 11) with a block body 300F attached to the cathode was used. The block body 300F has a block body 315 which is a triangular pyramidal block with two of its vertices cut off. The volume ratio of the block body was 23.2%, W / W0 was 0.32 to 1.0, L / L0 was 0.54 to 0.84, and H / H0 was 0.49 to 0.90. The irradiation test was performed in the same manner as in Example 1, except for the cathode. The effect on the vacuum level was evaluated as D, and it was difficult to reach the predetermined vacuum level, so the calculation of the increase ratio of the number of particles from the initial state and the evaluation of the removal efficiency were not performed.

[0106] Next, Comparative Example 4 was performed. Comparative Example 4 was carried out in the same manner as Example 1, except that the adhesive application area on the bonding surface to the inside of the cathode of the block body was set to 15%. As a result, the particle number increase ratio was 4.7%, the removal efficiency was rated A, and the effect on the vacuum level was rated A. However, although a properly bonded bonded substrate was obtained as a result of manufacturing the bonded substrate, damage was observed in components such as the cathode member constituting the high-speed atomic beam source.

[0107] [Table 1]

[0108] [Table 2]

[0109] In Examples 1 to 16, which are exemplary embodiments of the present invention, it was shown that by attaching block bodies to regions of the cathode member where particles generated by sputtering tend to accumulate, the emission of particle deposits is suppressed, and the adhesion of particles to the bonding target surface of the semiconductor substrate irradiated with a high-speed atomic beam is suppressed. Furthermore, it was shown that the increase ratio of the number of particles was 10 times or less, the emission of particle deposits was sufficiently suppressed, and bonding inhibition when bonding semiconductor substrates together was suppressed, thereby improving the manufacturing efficiency of the bonded substrate. In addition, by making the adhesive attachment area on the inner surface of the cathode member 25% or more, the decrease in vacuum level and the decrease in surface treatment efficiency can be suppressed, and damage to the cathode member can be suppressed, thereby improving the manufacturing efficiency of the bonded substrate. [Explanation of Symbols]

[0110] 100 cathode 101 Particle beam emission port 102 Inert gas inlet 103 Cathode component 103a Corner 103b side 110 Base 120 Top 130 Side view 140 Side view 150 Side view 160 Side view 200 Anode 300 block letters 301A1 Exposed surface 400 Adhesive 500 Fast atomic beam sources 700 bonded substrate 710 First semiconductor substrate 720 Second semiconductor substrate 711,721 Surfaces to be joined

Claims

1. The cathode of a high-speed atomic beam source, The cathode has six inner surfaces and is a hollow box shape inside. The six inner surfaces include a bottom surface, an upper surface facing and parallel to the bottom surface, and four side surfaces connecting the bottom surface and the upper surface, and the six inner surfaces are composed of six flat cathode members. The four aforementioned sides are such that opposing sides are parallel to each other. Of the four aforementioned sides, in one pair of opposing sides, an inert gas inlet for introducing an inert gas into the cathode is provided on one side, and a particle beam emission port for emitting a high-speed atomic beam outside the cathode is provided on the other side. The cathode member has a shape whose outline is formed by four corners and four sides connecting the corners. The cathode member constituting the inner surface of the cathode has a block body attachment area to which a block body is attached via an adhesive material, The block body attachment region is a region where the amount of sputtering dust reattached by sputtering is greater than the amount of the cathode member removed by sputtering caused by the use of the high-speed atomic beam source. The volume of the block body is 1% to 15% of the internal volume of the cathode. On the adhesive surface of the cathode of the block body to the interior, the adhesive surface area is 25% or more. A cathode in which the block body is made of graphite, glassy carbon, silicon, or silicon carbide.

2. The cathode according to claim 1, wherein the block body attachment area includes the corner portion.

3. The cathode according to claim 2, wherein the block body attachment area further includes the edge.

4. On the aforementioned upper surface, The cathode according to claim 2, wherein the ratio (W1 / W0) of the shortest distance W1 between the two block bodies provided at the two corner portions connected by the first diagonal to the length W0 of the first diagonal, which is the diagonal connecting the two corner portions of the upper surface, is 0.4 or more.

5. On the side where the inert gas inlet and the particle beam outlet are not provided, The cathode according to claim 2, wherein the ratio (L1 / L0) of the shortest distance L1 between the two block bodies provided at the two corner portions connected by the second diagonal to the length L0 of the second diagonal, which is the diagonal connecting the two corner portions of the side surface, is 0.5 or more.

6. On the side surface where the inert gas inlet is provided, The cathode according to claim 2, wherein the ratio (H1 / H0) of the shortest distance H1 between the two block bodies provided at the two corner portions connected by the third diagonal to the length H0 of the third diagonal, which is the diagonal connecting the two corner portions of the side surface, is 0.5 or more.

7. The cathode according to claim 2, wherein the exposed surface of the block body provided at the corner is a surface that is recessed in a substantially hemispherical shape toward the corner.

8. The cathode according to claim 1, wherein the cathode member is made of graphite, glassy carbon, silicon, or silicon carbide.

9. The cathode described in claim 1, A high-speed atomic beam source comprising an anode provided inside the cathode.

10. A method for manufacturing a bonded substrate in which a first semiconductor substrate and a second semiconductor substrate are stacked, An irradiation step of irradiating the bonding surface of the first semiconductor substrate and the bonding surface of the second semiconductor substrate with a high-speed atomic beam in a vacuum using the high-speed atomic beam source described in claim 9, A contact step to obtain a laminate having a bonding interface by bringing into contact the bonding target surface of the first semiconductor substrate and the bonding target surface of the second semiconductor substrate, which have been irradiated with the high-speed atomic beam, A method for manufacturing a bonded substrate, comprising:

11. The method for manufacturing a bonded substrate according to claim 10, further comprising a heat treatment step of heat-treating the laminate obtained in the bonding step to obtain a bonded substrate.

12. The method for manufacturing a bonded substrate according to claim 10, wherein the first semiconductor substrate and the second semiconductor substrate are each one of a 3C-SiC single crystal substrate, a 4H-SiC single crystal substrate, a 6H-SiC single crystal substrate, and a SiC polycrystalline substrate.

13. The method for manufacturing a bonded substrate according to claim 10, wherein the high-speed atomic beam includes argon, neon, or xenon.

14. A method for regenerating a cathode according to claim 1, A block body removal step, which involves removing the block body from the block body attachment area of ​​the cathode member that constitutes the cathode after use in a high-speed atomic beam source, A method for regenerating a cathode, comprising the step of attaching a new block body to the block body attachment area of ​​the cathode member from which the block body has been removed.

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