JP2023144787A - Negative electrode, high-speed atom beam radiation source, manufacturing method of bonding substrate, and reproduction method of negative electrode - Google Patents

Abstract

To suppress discharge of a particle accumulation from a high-speed atom beam radiation source.SOLUTION: In a negative electrode of a high-speed atom beam radiation source, the negative electrode includes six inner surfaces, where an inner part is a hollow box shape, and a bottom surface, an upper surface, and four side surfaces are provided. In a pair of side surfaces of the two opposed pairs of side surfaces of the four side surfaces, one of the side surfaces is provided with an inactive gas introduction port introducing an inactive gas into the negative electrode, and the other side surface is provided with a particle line discharge outlet discharging the high-speed atom beam to an external part of the negative electrode. In a flat surface of a negative electrode member constructing the inner surface of the negative electrode, a block body adhesion region to which a block body is adhered via an adhesive material is provided. The region is the region where a re-adhesion amount of a spattering dust generated by the spattering is larger than a removing amount of the negative electrode member by spattering generated by the use of the high-speed atom beam radiation source. A volume of the block body is 1% to 15% of a volume rate to a volume of the inner part of the negative electrode.SELECTED DRAWING: Figure 3

Description

The present invention relates to a cathode, a fast atomic beam source, a method for manufacturing a bonded substrate, and a method for regenerating a cathode.

One of the techniques for bonding substrates together is room-temperature bonding technology using high-speed atomic beam irradiation. This process involves irradiating the surfaces of the substrates to be bonded with an atomic beam to remove surface contamination and oxide films, as well as exposing the dangling bonds and activating the surfaces. This is a technology that joins substrates by overlapping them and pressing them together at room temperature.

As an atomic beam source used for room temperature bonding, a saddle field type fast atomic beam source is used (for example, see Patent Document 1).The saddle field type fast atomic beam source has an anode inside. An inert gas such as argon (Ar) gas (hereinafter, argon gas will be explained as an example) is supplied into the cathode housing, and the inert gas atoms are ionized by applying a voltage between the anode and the cathode. An Ar atomic beam is taken out from an opening provided in a part and irradiated onto the substrate. In addition, most of the Ar ions recombine with electrons on the way to the cathode and become a neutral Ar atomic beam. Therefore, there is little electrostatic repulsion between Ar atoms, resulting in a highly directional atomic beam. It has the characteristic of irradiating the substrate.

International Publication No. 2017/038476

In the substrate bonding technology using the above-mentioned fast atomic beam source (FAB gun, (Fast Atom Beam)), along with the Ar atomic beam, some of the particles generated in the fast atomic beam source fly out of the gun and adhere to the substrate. However, it may become a factor that inhibits bonding. That is, in the high-speed atomic beam source, a part of the Ar atomic beam is irradiated onto the cathode housing to cause a sputtering phenomenon, and as a result, particles due to fragments of the cathode housing are generated and become particles. Furthermore, on the inner surface of the cathode of the fast atom beam source, the above-described sputtering phenomenon and the redeposition of particles generated by the sputtering (hereinafter sometimes referred to as "redeposition") occur simultaneously. Particles become aggregates that accumulate at the corners of the cathode, forming particle deposits. As this particle deposit increases, it becomes more likely to peel off and fall from the inner surface of the cathode, fly out from the high-speed atomic beam source, and become a major factor in inhibiting bonding when bonding substrates together.

Therefore, an object of the present invention is to provide a cathode, a fast atomic beam source, a method for manufacturing a bonded substrate, and a method for regenerating a cathode, which can suppress the emission of particle deposits from a fast atomic beam source. shall be.

The cathode of the present invention is a cathode for a high-speed atomic beam source, and the cathode has a hollow box shape with six inner surfaces, and the six inner surfaces include a bottom surface and a bottom surface facing the bottom surface. and includes an upper surface 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, and the four inner surfaces are composed of six flat cathode members. The side surfaces are parallel to each other, and among the four side surfaces, one set of the two opposing side surfaces includes an inert gas for introducing an inert gas into the cathode. An inlet is provided on the other side, and a particle beam emitting port for emitting a high-speed atomic beam to the outside of the cathode is provided on the other side. The block body has a shape in which an outline is formed by two sides, and has a block body attachment area in which a block body is pasted via an adhesive material on a plane of the cathode member constituting the inner surface of the cathode, and the block body The pasting area is an area where the amount of redeposited sputter dust generated by the sputtering is larger than the amount of the cathode member removed by the sputtering generated by using the high speed atomic beam source, and the volume of the block body is has a volume ratio of 1% to 15% with respect to the internal volume of the cathode.

In the cathode of the present invention, the block attachment area may include the corner portion.

In the cathode of the present invention, the block attachment area may further include the side.

In the cathode of the present invention, in the upper surface, the length W0 of the first diagonal line, which is the diagonal line connecting the two corner portions of the upper surface, is provided at the two corner portions connected by the first diagonal line. A ratio (W1/W0) of the shortest distance W1 between the blocks may be 0.4 or more.

In the cathode of the present invention, in the side surface where the inert gas inlet and the particle beam outlet are not provided, with respect to the length L0 of a second diagonal that is a diagonal connecting the two corners of the side surface, A ratio (L1/L0) of the shortest distance L1 between the blocks provided at the two corner portions connected by the second diagonal line may be 0.5 or more.

In the cathode of the present invention, in the side surface provided with the inert gas inlet, the third diagonal line is connected to the length H0 of the third diagonal line, which is a diagonal line connecting the two corners of the side surface. A ratio (H1/H0) of the shortest distance H1 between the block bodies provided at the two corner portions may be 0.5 or more.

In the cathode of the present invention, the exposed surface of the block provided at the corner may be a substantially hemispherically recessed surface toward the corner.

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

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

The fast atomic beam source of the present invention includes the cathode of the present invention and an anode provided inside the cathode.

A method for manufacturing a bonded substrate according to the present invention is a method for manufacturing a bonded substrate in which a first semiconductor substrate and a second semiconductor substrate are stacked, the method comprising: using a fast atomic beam source according to the present invention; an irradiation step of irradiating a surface to be bonded of the first semiconductor substrate and a surface to be bonded of the second semiconductor substrate with a high-speed atomic beam in a vacuum; and the first semiconductor substrate irradiated with the high-speed atomic beam. and a contact step of bringing the surface to be bonded of the second semiconductor substrate into contact with the surface to be bonded of the second semiconductor substrate to obtain a laminate having a bonding interface.

The method for manufacturing a bonded substrate of the present invention may further include a heat treatment step of heat-treating the laminate obtained in the bonding step to obtain a bonded substrate.

In the method for manufacturing a bonded substrate of the present invention, the first semiconductor substrate and the second semiconductor substrate may be a 3C-SiC single crystal substrate, a 4H-SiC single crystal substrate, a 6H-SiC single crystal substrate, or a SiC polycrystalline substrate, respectively. It may be any crystal substrate.

In the method for manufacturing a bonded substrate of the present invention, the high-speed atomic beam may contain any one of argon, neon, and xenon.

The cathode regeneration method of the present invention includes a block body removal step of removing a block body from the block body pasting area of the cathode member constituting the cathode after being used in a fast atom beam source; The method includes a pasting step of pasting a new block body on the block body pasting area of the cathode member.

With the cathode of the present invention, by using the cathode of the present invention in a fast atomic beam source, emission of particle deposits from the fast atomic beam source can be suppressed. This suppresses particles from adhering to the surfaces to be bonded of the semiconductor substrates, suppresses the occurrence of bonding inhibition when bonding the semiconductor substrates, and improves the manufacturing efficiency of the bonded substrates.

Since the fast atomic beam source of the present invention includes the cathode of the present invention, emission of particle deposits from the fast atomic beam source can be suppressed. This suppresses particles from adhering to the surfaces to be bonded of the semiconductor substrates, suppresses the occurrence of bonding inhibition when bonding the semiconductor substrates, and improves the manufacturing efficiency of the bonded substrates.

In the method for manufacturing a bonded substrate of the present invention, since the surface to be bonded of the substrate is irradiated using a fast atomic beam source equipped with the cathode of the present invention, particle deposits are not emitted from the fast atomic beam source. Therefore, particles can be prevented from adhering to the surface to be welded. Thereby, the production efficiency of bonded substrates can be increased by suppressing the occurrence of bonding inhibition when bonding the substrates and improving the yield.

With the method for regenerating a cathode of the present invention, a cathode that has been used for a certain period of time can be regenerated into a state in which emission of particle deposits can be suppressed again through a simple process. Therefore, it is possible to suppress the emission of particle deposits from the high-speed atomic beam source, increase the production efficiency of the bonded substrate, and extend the life of the cathode.

FIG. 1 is a perspective view schematically showing a conventional high-speed atomic beam source. FIG. 2 is a plan view schematically showing the state of the inner surface of a cathode member that constitutes a cathode after using a conventional high-speed atomic beam source. 1 is a perspective view schematically showing a fast atomic beam source according to the present embodiment, which is used in Example 1, and a block body attached to the inside of a cathode. FIG. (A) is a plan view showing the upper surface of the cathode of this embodiment, (B) is a cross-sectional view of the cathode of this embodiment parallel to the XY plane, and (C) and (D) are block diagrams. It is a figure which shows the modification of a body. (A) is a plan view showing a side surface 150 of the cathode of this embodiment, (B) is a sectional view of a cross section parallel to the YZ plane of the cathode of this embodiment, and (C) is a plan view of the cathode in a modified example. FIG. 2 is a sectional view of the YZ plane. (A) is a plan view showing a side surface 140 of the cathode of this embodiment, (B) is a cross-sectional view of a cross section parallel to the XZ plane of the cathode of this embodiment, and (C) is a plan view of the cathode in a modified example. FIG. 2 is a sectional view of the XZ plane. FIG. 3 is a perspective view schematically showing a high-speed atomic beam source used in Example 2 and a block body attached to the inside of a cathode. FIG. 7 is a perspective view schematically showing a high-speed atomic beam source used in Example 3 and a block body attached to the inside of a cathode. FIG. 7 is a perspective view schematically showing a high-speed atomic beam source used in Example 4 and a block body attached to the inside of a cathode. FIG. 3 is a perspective view schematically showing a high-speed atomic beam source used in Comparative Example 2 and a block body attached to the inside of a cathode. FIG. 7 is a perspective view schematically showing a high-speed atomic beam source used in Comparative Example 3 and a block body attached to the inside of a cathode. FIG. 3 is a diagram illustrating a method for manufacturing a bonded substrate according to an embodiment of the present invention. FIG. 3 is a diagram illustrating a method for regenerating a cathode according to an embodiment of the present invention.

[Fast atomic beam source, cathode, and cathode member]
A fast atomic beam source, a cathode, and a cathode member according to an embodiment of the present invention will be described with reference to the drawings.

The fast atomic beam source of this embodiment is a saddle field type fast atomic beam source, in which an inert gas is supplied inside and a fast atomic beam of ionized inert gas is emitted from a particle beam emission port to the outside. It is something that is released into the atmosphere. Furthermore, the fast atomic beam source of this embodiment can be used, for example, to perform surface treatment on the surfaces of the substrates to be bonded before the bonding process when manufacturing a bonded substrate in which two semiconductor substrates are bonded together. It will be done. That is, it is used for the purpose of performing surface treatment for activating the surface of the surface to be bonded by irradiating the surface of the substrate to be bonded with a high-speed atomic beam emitted from a high-speed atomic beam source.

FIG. 1 shows a fast atomic beam source 800, which is an example of a conventional fast atomic beam source. A conventional high-speed atomic beam source 800 includes a cathode 900 and an anode 200 provided inside the cathode 900. Note that in the fast atomic beam source 800, cathode 900, and anode 200 of this embodiment, the arrow X direction, arrow Y direction, and arrow Z direction in FIG. 1 are the width direction, depth direction, and height direction, respectively. The fast atomic beam source 800 has a box shape made up of six plate-shaped cathode members 903, and has a bottom surface 910, a top surface 920 facing the bottom surface 910, and four side surfaces connecting the bottom surface 910 and the top surface 920. 930, 940, 950, 960. Furthermore, the bottom surface 910 and the top surface 920, the side surfaces 930 and 940, and the side surfaces 950 and 960 are parallel to each other. Further, a particle beam emitting port 901 for emitting a high-speed atomic beam is formed on the side surface 930, and an inert gas introduction port 902 for introducing an inert gas into the inside of the cathode 900 is provided on the side surface 940. .

FIG. 3 shows a fast atom beam source 500 according to one embodiment of the invention. This differs from the conventional high-speed atomic beam source 800 shown in FIG. 1 in that a block body 300 is attached inside the cathode 100.

A fast atomic beam source 500 of this embodiment shown in FIG. 3 includes a cathode 100 and an anode 200 provided inside the cathode 100. In addition, in the fast atomic beam source 500, cathode 100, and anode 200 of this embodiment, the arrow X direction, arrow Y direction, and arrow Z direction in FIG. 3 are defined as the width direction, depth direction, and height direction, respectively.

The cathode 100 of this embodiment has a hollow box shape with six inner surfaces. For example, the cathode 100 has a rectangular parallelepiped shape with inner dimensions of 56 mm in width (w in FIG. 3), 64 mm in depth (d in FIG. 3), and 102 mm in height (h in FIG. 3). The six inner surfaces include a bottom surface 110, a top surface 120 facing the bottom surface 110, and four side surfaces 130, 140, 150, and 160 that connect the bottom surface 110 and the top surface 120.

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

Of the two sets of opposing side surfaces (side surfaces 130, 140 and side surfaces 150, 160), the side surfaces 130, 140 are provided with a particle beam outlet 101 and an inert gas inlet 102. That is, the side surface 130 is provided with a particle beam emitting port 101 through which a high-speed atomic beam of an inert gas ionized inside the cathode 100 is emitted. Furthermore, an inert gas introduction port 102 for introducing an inert gas into the cathode 100 is provided on a side surface 140 that faces the side surface 130 in the direction of arrow Y. In this embodiment, the particle beam emission port 101 has a total of 64 circular through holes each having 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 the side surface 130. It is provided. Further, the inert gas inlet 102 is provided with one circular through hole with a diameter of 3 mm near the center of the side surface 140. The shape, number, and location of the particle beam outlet and the inert gas inlet are not limited to those in this embodiment, and may be in other forms.

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). Further, the anode 200 has a cylindrical shape with a cross-sectional diameter of 10 mm and a height dimension that is approximately the same as the height of the cathode 100. The anode 200 has a circular cross section parallel to the XY plane, and a cylindrical central axis parallel to the Z direction. Further, as shown in FIG. 4(A), the two anodes 200 are arranged between the central axes of the two anodes 200 at the middle position in the depth direction of the cathode 100 (positions 32 mm from the side surfaces 130 and 140, respectively). They are spaced apart from each other so that the distance is 36 mm.

Further, as the material of the anode, graphite, glassy carbon, silicon, silicon carbide, etc. can be used. In addition, tungsten, molybdenum, titanium, nickel, and alloys and compounds thereof can be used.

Further, a negative electrode of direct current is connected to the cathode 100, and a positive electrode of direct current is connected to the anode 200, and a high voltage of, for example, about 0.5 kV to 5 kV is applied. This generates an electric field, and the inert gas introduced into the cathode 100 from the inert gas inlet 102 is ionized, generating plasma between the two anodes 200. Furthermore, 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 (FIG. 12). At this time, the flow of the inert gas is adjusted so that the irradiation current is, for example, about 10 mA to 100 mA.

Next, the cathode member will be explained with reference to the fast atomic beam source 500 shown in FIG.

The cathode member 103 has a plate shape, and has a shape whose outline is composed of four corner parts 103a and four sides 103b connecting the corner parts 103a. The thickness can be, for example, about 1 mm to 5 mm. Further, the plane of the cathode member constituting the inner surface of the cathode 100 has a block attachment area where the block body 300 is attached via the adhesive material 400. In the cathode 100 of this embodiment, as shown in FIG. 3, a triangular pyramid-shaped first block body is provided inside the apex of the cathode (a portion formed by the corner portion 103a of the cathode member 103) as a block body 300. 301, a triangular prism-shaped second block body 302, third block body 303, and fourth block body 304 are attached to the inside of the side. Note that the through holes of the particle beam discharge port 101 and the inert gas introduction port 102 provided on the side surfaces 130 and 140 are not blocked by the block body 300 or the adhesive material 400.

Further, the cathode member of this embodiment may be made of, for example, graphite, glassy carbon, silicon, or silicon carbide. In addition, tungsten, molybdenum, titanium, nickel, and alloys and compounds thereof can be used.

In general, when using the conventional high-speed atomic beam source 800 shown in FIG. Particles are generated due to the debris, and these become particles. Further, the particles may be emitted from the particle beam emission port 901 or may be reattached and deposited on the surface of the cathode member. That is, in the cathode member constituting the cathode 900, the sputtering phenomenon and the re-adhesion of particles generated by the sputtering phenomenon to the surface of the cathode member occur simultaneously. As the thickness of the deposited layer in which particles are deposited due to the sputtering phenomenon increases, it becomes easier to peel off and fall from the inner surface of the cathode 900, and is emitted from the high speed atomic beam source 800 as larger particles, bonding the substrates together. This is a major factor in the occurrence of bonding inhibition when

In the cathode member of this embodiment, in the block body pasting area, the amount of re-deposition of sputtered dust generated by sputtering is larger than the amount of cathode member removed by sputtering generated by using the high-speed atomic beam source 500 ( In other words, it is a region (in which redeposition is easier to perform than sputtering). Further, the volume of the block body 300 is a volume ratio of 1% to 15% with respect to the internal volume of the cathode 100 (that is, in the cathode 100 of FIG. 3, w×h×d=352512 (mm ³ )). . Further, the volume ratio (%) of the block body can be calculated by the formula “volume of the block body/volume inside the cathode×100 (%)”. In calculating the volume ratio of the block body, it is assumed that the particle beam discharge port 101 and the inert gas inlet port 102 provided on the side surfaces 130 and 140 have no holes and are flush with each other. If the volume ratio of the block body is too small, it becomes difficult to sufficiently suppress the release of particle deposits. Furthermore, when the volume ratio of the block body is increased, the accumulation of particles tends to be suppressed, and the emission of particle deposits to the outside of the high-speed atomic beam source 500 tends to be suppressed. On the other hand, as the volume ratio of the block body increases, the emission efficiency of the high-speed atomic beam tends to decrease, and the processing time tends to increase in order to sufficiently perform surface treatment on the surface of the semiconductor substrate to be bonded. In other words, if the volume ratio of the block body is too large, the influence on the electric field inside the cathode 100 becomes large and the emission efficiency of the high-speed atomic beam decreases, resulting in surface contamination and oxide film on the surface of the semiconductor substrate to be bonded. The removal efficiency may be significantly reduced, resulting in poor manufacturing efficiency.

Further, FIG. 4(A) is a plan view of the upper surface 120 viewed from inside the cathode 100. In FIG. 4A, W0 and W1 are shown slightly shifted for illustration purposes, but both are on a diagonal line. Note that W0, W2, L0, L1, L2, H0, H1, and H2 in FIGS. 4(B), 5(A)(B), and 6(A)(B) are also on the diagonal line. .

Considering the volume ratio of the block body 300 described above, in the upper surface 120, the two corners connected by the first diagonal 121, which is the diagonal connecting the two corner parts 103a of the upper surface 120, The ratio (W1/W0) of the shortest distance between the first block bodies 301 provided at the corner 103a (the distance between the exposed surfaces 301a of the first block bodies 301 on the first diagonal line 121) W1 is 0.4 or more It is more preferable that it is 0.5 or more. By setting W1/W0 within an appropriate range, emission of particle deposits can be sufficiently suppressed.

Moreover, FIG. 4(B) is a cross-sectional view showing a cut surface 170 passing through the center P of the cathode, which is an example of a cut surface of the cathode 100 parallel to the XY plane. FIG. 3 is a cross-sectional view showing a cut plane 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 described above, in the cut plane 170, the shortest distance ( The ratio (W2/W0) of W2 (the distance between the exposed surfaces 302a of the second block bodies 302 on the diagonal line 171) may be 0.4 or more, and is more preferably 0.5 or more. By setting W2/W0 within an appropriate range, emission of particle deposits can be sufficiently suppressed. Note that in this specification, if no block body is provided on the side 103b of the cut plane of the cathode 100 parallel to the XY plane, W2/W0 is assumed to be 1.0.

FIG. 5A is a plan view of the side surface 150 viewed from inside the cathode 100. Considering the volume ratio of the block body 300 described above, in the side surface 150 where the inert gas inlet port 102 and the particle beam discharge port 101 are not provided, the second diagonal line connecting the two corner portions 103a of the side surface 150 is The shortest distance between the first block bodies 301 provided at the two corner parts 103a connected by the second diagonal line 151 with respect to the length L0 of the diagonal line 151 (the exposed surface 301a of the first block body 301 on the second diagonal line 151) The ratio of L1 (L1/L0) may be 0.5 or more, and is more preferably 0.6 or more. By setting L1/L0 within an appropriate range, the release of particle deposits can be sufficiently suppressed.

FIG. 5B is a cross-sectional view showing a cut surface 180 passing through the center P of the cathode, which is an example of a cut surface of the cathode 100 parallel to the YZ plane. Considering the volume ratio of the block body 300 described above, in the cut plane 180, the shortest distance between the third block bodies 303 provided on the side 103b connected by the diagonal line 181 with respect to the length L0 of the diagonal line 181 connecting the side 103b. The ratio (L2/L0) of L2 (distance between the exposed surfaces 303a of the third block bodies 303 on the diagonal line 181) may be 0.5 or more, and is more preferably 0.6 or more. By setting L2/L0 within an appropriate range, emission of particle deposits can be sufficiently suppressed. Note that in this specification, when no block body is provided on the side 103b of the cut plane of the cathode 100 parallel to the YZ plane, L2/L0 is assumed to be 1.0.

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

FIG. 6(B) is a cross-sectional view showing a cut surface 190 passing through the center P of the cathode, which is an example of a cut surface of the cathode 100 parallel to the XZ plane. Considering the volume ratio of the block body 300 described above, in the cut plane 190, the shortest distance between the fourth block bodies 304 provided on the side 103b connected by the diagonal line 191 with respect to the length L0 of the diagonal line 191 connecting the side 103b. The ratio (H2/H0) of H2 (the distance between the exposed surfaces 304a of the fourth block bodies 304 on the diagonal line 191) may be 0.5 or more, and is more preferably 0.6 or more. By setting H2/H0 within an appropriate range, the release of particle deposits can be sufficiently suppressed. Note that in this specification, if no block is provided on the side 103b of the cut plane of the cathode 100 parallel to the YZ plane, H2/H0 is assumed to be 1.0.

Further, the block body 300 of this embodiment can be made of, for example, graphite, glassy carbon, silicon, or silicon carbide, similarly to the cathode member. In addition, tungsten, molybdenum, titanium, nickel, and alloys and compounds thereof can be used.

Further, the adhesive force of the adhesive material 400 needs to be such that the block attached to the cathode member does not fall into the inside of the cathode 100. That is, in the adhesive material 400, the adhesive strength of the surface on the block body 300 side and the surface on the flat side of the cathode member can be, for example, 5 N/25 mm to 15 N/25 mm.

Further, the thickness of the adhesive material 400 is not particularly limited, but may be, for example, about 50 μm to 300 μm.

A region in the cathode 100 of the fast atomic beam source 500 where the amount of redeposition of particles generated by sputtering is greater than the amount of cathode material removed by sputtering that occurs when using the fast atomic beam source 500. is a region that is difficult to be irradiated with the high-speed atomic beam. Therefore, by pasting the block body 300, the difficulty of being irradiated with the high-speed atomic beam is resolved, and the shape of the inner surface of the cathode 100 becomes a shape in which it is difficult for particles to accumulate. The difference in the amount of deposition on the cathode member depending on the position can be reduced. That is, by pasting the block body, it is possible to eliminate a shape in which particles tend to accumulate inside the cathode. As a result, by using the cathode 100 configured with the cathode member of this embodiment in the fast atomic beam source 500 and activating the surface to be bonded of the semiconductor substrate to be bonded, a large amount of radiation from the fast atomic beam source can be generated. Release of particle deposits can be suppressed. As described above, it is possible to suppress the occurrence of bonding inhibition when bonding substrates to each other, and increase the manufacturing efficiency of bonded substrates.

Here, FIG. 2 is a plan view schematically showing the state of a side surface 930, which is an example of a cathode member constituting a cathode after using a conventional high-speed atomic beam source. In FIG. 2, the cathode is placed so that its inner surface is visible. A fast atomic beam source 800 (FIG. 1) using the cathode member (side surface 930) shown in FIG. It is the composition. When the conventional fast atomic beam source 800 is used, the inside part of the vertex of the cathode (the part formed by the corner part 903a of the cathode member) and the part inside the side of the cathode (the part formed by the side 903b of the cathode member) Since the area (part 2) is surrounded by the cathode member and is less likely to be irradiated with the high-speed atomic beam than other parts, the amount of deposition on the cathode member due to redeposition is greater than the amount of cathode member removed by sputtering. A deposited layer due to redeposition is likely to occur. That is, as shown in FIG. 2, particles generated by the sputtering phenomenon tend to re-adhere and accumulate in a region S close to the contour of the cathode member including four corners 903a and sides 903b of the cathode member.

For this reason, as shown in FIG. 3, it is preferable that the block attachment area of the cathode member (the area where the block body 300 is attached) includes the corner portion 103a of the cathode member. Moreover, it is preferable that the block attachment area further includes the side 103b of the cathode member. By including the corner portion 103a and the side 103b in the block body attachment area, it is possible to reduce the area where the amount of deposition due to redeposition is larger than the amount removed by sputtering, which is particularly difficult to be irradiated with the high-speed atomic beam, and where particles are deposited. It is possible to more effectively suppress the release of particle deposits.

Further, as shown in FIGS. 3 to 11, the shape of the block body 300 is preferably a shape that follows the inner part of the apex or side of the cathode 100 in the internal space of the cathode 100. As the shape of such a block body 300, a triangular pyramid, a triangular prism, a cube, a rectangular parallelepiped, and other shapes can be used, and a plurality of blocks of different shapes and sizes may be combined.

For example, in the cathode 100 of the present embodiment shown in FIG. A fourth block body 304 is attached. The first block body 301 has a shape that follows the inner surface of the corner of the cathode formed by the corner of the cathode member, and three of its four faces are pasted. The second block body 302, the third block body 303, and the fourth block body 304 each have a shape along the inside of the side, and two rectangular faces out of the five faces are pasted.

Further, FIG. 4C is a plan view of the upper surface 120 seen from inside the cathode 100, and shows a high-speed atomic beam source having the cathode 100 to which a block body 300A, which is a modified example of the block body 300, is attached. It is a figure showing 500A. The broken line in FIG. 4C indicates that the exposed surface of the block body is recessed toward the corner portion 103a and the side 103b, as will be described later. As shown in FIG. 4(C), the exposed surface 301A1 of the block body (first block body 301A) provided at the corner portion 103a has a substantially hemispherical shape toward the corner portion 103a, as shown by the broken line. It has a concave surface. In this way, since the exposed surface 301A1 of the first block body 301A has a substantially hemispherical concave surface toward the corner portion 103a, compared to the case where the first block body 301 that does not have a concave surface is attached. As a result, the boundary between the first block body 301A and the cathode member becomes gentle, and the portion that is difficult to be irradiated 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, suppressing the accumulation of particles resulting from sputtering, and further suppressing the release of large particle deposits. can do.

4(D), FIG. 5(C), and FIG. 6(C) are cross-sectional views of the cathode 100 parallel to the XY plane, the YZ plane, and the XZ plane, and are views showing modified examples of the block body 300. be. As shown in FIG. 4(C), FIG. 4(D), FIG. 5(C), and FIG. 6(C), the block bodies (second block body 302A, third block body 303A, third block body 303A, The exposed surfaces 302A1, 303A1, and 304A1 of the four-block body 304A) have surfaces concave in a substantially semi-cylindrical shape toward the side 103b. As described above, since the exposed surface of the block body has a substantially semi-cylindrical concave surface toward the side 103b, the connection between the block body and the cathode member is improved compared to the case where a block body without a concave surface is attached. The boundary part becomes smooth, and the part that is difficult to be irradiated 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, suppressing the accumulation of particles resulting from sputtering, and further suppressing the release of large particle deposits. can do.

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

The method of manufacturing a bonded substrate of this embodiment is a method of manufacturing a bonded substrate in which a first semiconductor substrate 710 and a second semiconductor substrate 720 are stacked, and includes the method of manufacturing a bonded substrate in which a first semiconductor substrate 710 and a second semiconductor substrate 720 are stacked. An irradiation step of irradiating the surface 711 of the first semiconductor substrate 710 to be bonded and the surface 721 of the second semiconductor substrate 720 to be bonded with a high-speed atomic beam 510 in a vacuum, and irradiation with the high-speed atomic beam 510 using contacting the bonding target surface 711 of the first semiconductor substrate 710' and the bonding target surface 721 of the second semiconductor substrate 720' to obtain a laminate 700 having a bonding interface 730. . Further, the method for manufacturing a bonded substrate according to the present embodiment may further include a heat treatment step of heat-treating the laminate 700 obtained in the bonding step to obtain a bonded substrate.

The bonding apparatus 600 holds a housing, two high-speed atomic beam sources 500, a vacuum pump (not shown) that evacuates the inside of the housing, a first semiconductor substrate 710, and a second semiconductor substrate 720. , a holding means (not shown) for moving the first semiconductor substrate 710 and the second semiconductor substrate 720 to predetermined positions in each manufacturing process. As shown in FIG. 12, the two high-speed atomic beam sources 500 irradiate a high-speed atomic beam 510 onto a surface to be bonded 711 of a first semiconductor substrate 710 and a surface to be bonded 721 of a second semiconductor substrate 720. is set up. In this embodiment, the first semiconductor substrate 710 and the second semiconductor substrate 720 are each irradiated with the fast atomic beam 510. , at least one of the second semiconductor substrates 720 may be irradiated.

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

First, an irradiation process is performed. In the irradiation step, as shown in FIG. 12A, a fast atomic beam 510 is applied from a fast atomic beam source 500 to a surface 711 of the first semiconductor substrate 710 to be bonded and a surface 721 of the second semiconductor substrate 720 to be bonded. This is the process of irradiating the As a result, a first semiconductor substrate 710' and a second semiconductor substrate 720' with activated surfaces 711 and 721 to be bonded are obtained.

Activation of the surfaces 711 and 721 to be bonded refers to interface termination components such as oxygen, hydrogen, and hydroxyl groups (OH groups) on the surfaces 711 and 721 to be bonded of the first semiconductor substrate 710 and the second semiconductor substrate 720; This refers to removing the oxide film and forming dangling bonds.

Next, a contact step is performed. As shown in FIG. 12(B), the first semiconductor substrate 710', the first semiconductor substrate 710', and the The second semiconductor substrate 720' is moved. The inside of the casing 600 is pressurized to a predetermined pressure (for example, 100 kgf (0.98 kN)). The first semiconductor substrate 710' and the second semiconductor substrate 720' are bonded by holding for a predetermined time (for example, 3 minutes). The contacting step is thus completed, and a laminate 700 (FIG. 12C) having a bonding interface 730 is obtained.

Next, a heat treatment step is performed. A bonded substrate of the first semiconductor substrate 710 and the second semiconductor substrate 720 is obtained by heat-treating the obtained laminate 700 by setting the inside of the casing of the bonding device 600 to about 300° C., for example.

In the method for manufacturing a bonded substrate of this embodiment, the first semiconductor substrate 710 and the second semiconductor substrate 720 are respectively a 3C-SiC single crystal substrate, a 4H-SiC single crystal substrate, a 6H-SiC single crystal substrate, and a SiC It can be any of the polycrystalline substrates.

Furthermore, the high-speed atomic beam 510 can contain any one of argon, neon, and xenon.

According to the method for manufacturing a bonded substrate of the present embodiment, the surfaces 711 and 721 to be bonded of the first semiconductor substrate 710 and the second semiconductor substrate 720 are irradiated using the fast atomic beam source 500 including the cathode 100. Therefore, emission of particle deposits from the high-speed atomic beam source 500 is suppressed, and adhesion of particles to the surfaces 711 and 721 to be welded can be suppressed. Thereby, the production efficiency of the bonded substrate can be increased by suppressing the occurrence of bonding inhibition when bonding the first semiconductor substrate 710 and the second semiconductor substrate 720 and improving the yield.

[Cathode regeneration method]
Next, a cathode regeneration method according to an embodiment of the present invention will be described with reference to FIG. 13. In FIG. 13, the cathode 100 of the fast atomic beam source 500 will be explained as an example.

The cathode regeneration method of this embodiment is applied to the purpose of regenerating the cathode 100 of the embodiment described above. The cathode regeneration method of the present embodiment includes a block body removal step (S1) of removing the block body 300' from the block body attachment area of the cathode member that constitutes the cathode 100' after being used in the fast atomic beam source 500. , a pasting step (S2) of pasting a new block body 300 on the block body pasting area of the cathode member from which the block body 300' has been removed.

The specific procedure will be explained with reference to FIG. 13. First, the anode 200 is removed from the high-speed atomic beam source 500 after being used for a certain period of time. First, in the adhesive removal step (S1), from the cathode 100', the block body 300' (in this embodiment, the first block body 301', the second block body 302', the third block body 303', the fourth The block body 304') is removed to obtain a cathode member from which the adhesive has been removed. Next, in the pasting step (S2), new 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) having a predetermined shape are attached. Paste it again on the block body pasting area of the cathode member. Note that since the adhesive strength of the adhesive material 400 is reduced by removing the block body 300', when the adhesive material 400 is also removed and a new block body 300 is pasted, it is preferable to use a new adhesive material 400 as well. .

In the manner described above, a cathode that has been used for a certain period of time can be regenerated to obtain a regenerated cathode 100.

In the cathode 100 of this embodiment, particle accumulation is suppressed compared to conventional cathodes, but it is thought that particles may accumulate in the block body attachment area of the cathode 100 after being used for a certain period of time or more. There is a possibility that the deposited particles may fall off and be emitted to the outside of the high-speed atomic beam source 500. Therefore, with the cathode regeneration method of the present embodiment, even if particles are deposited on the cathode 100 after being used for a certain period of time, the cathode 100 can be removed through a simple process to sufficiently suppress the release of particle deposits again. It can be regenerated in a state where it can be played. Therefore, the emission of particle deposits from the high-speed atomic beam source 500 is suppressed to improve the production efficiency of bonded substrates, and the cathode member does not have to be replaced in its entirety due to particle deposits, thereby extending the life of the cathode. It is possible to aim for

Note that the present invention is not limited to the embodiments described above, but includes other steps that can achieve the object of the present invention, and variations of the embodiments described above are also included in the present invention.

In addition, the best configuration, method, etc. for carrying out the present invention have been disclosed in the above description, but the present invention is not limited thereto. That is, although the present invention has been specifically described mainly with respect to specific embodiments, there may be changes in shape, material, quantity, Various modifications can be made by those skilled in the art in other detailed configurations. Therefore, the descriptions in which the shapes, materials, etc. disclosed above are limited are provided as examples to facilitate understanding of the present invention, and are not intended to limit the present invention. Descriptions of names of members that exclude some or all of the limitations such as these are included in the present invention.

EXAMPLES Hereinafter, the present invention will be explained in more detail with reference to Examples and Comparative Examples of the present invention, but the present invention is not limited to these Examples in any way.

[Example 1]
As the cathode, the cathode 100 (FIG. 3) of the embodiment described above was used. That is, 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. Further, the cathode member and the block body were made of graphite, and a block body 300 having the dimensions shown in FIG. 3 was attached. The adhesive material has an adhesive force of 10 N/25 mm on both the surface to be attached to the cathode member and the surface exposed inside the cathode, and a thickness of 100 μm.The adhesive material is applied to the entire contact surface between the block body 300 and the cathode member. pasted. 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%. Also, the shortest distance W (W1 or W2) between the block bodies 300 (first block bodies 301 or second block bodies 302) with respect to the length W0 of the diagonal shown in FIGS. 4(A) and 4(B) The ratio (W/W0) was 0.73 to 0.92. Furthermore, the shortest distance L (L1 or L2) ratio (L/L0) was 0.81 to 0.94. Furthermore, the shortest distance H (H1 or The ratio of H2) (H/H0) was 0.79 to 0.94.

Further, as the anodes 200, two cylindrical graphite anodes each having a diameter of 10 mm and a length of 100 mm were used. As shown in FIGS. 3 and 4, the two anodes 200 are connected to each other at the middle position in the depth direction of the cathode 100 (positions 32 mm from the side surfaces 130 and 140, respectively) through an insulating member. They were fixed to the bottom surface 110 and the top surface 120 at a distance from each other so that the distance between the center axes was 36 mm.

As the inert gas, argon (Ar) gas was introduced into the cathode 100 from an inert gas inlet. The acceleration voltage for high-speed atomic beam irradiation from the high-speed atomic beam source 500 was 1 kV, and the Ar gas flow was adjusted so that the irradiation current was 30 mA. As the first semiconductor substrate and the second semiconductor substrate, silicon substrates having a diameter of 152 mm (6 inches) and a thickness of 625 μm were used.

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

Furthermore, it was predicted that by attaching the block to the cathode, the emission efficiency of the high-speed atomic beam would be reduced, and the efficiency of removing surface contamination and oxide film on the surface of the semiconductor substrate to be bonded would be reduced. Therefore, in order to evaluate the removal efficiency of surface contamination and oxide film on the surfaces to be bonded, a silicon thermal oxide film of known thickness was used instead of the semiconductor substrate used to manufacture the bonded substrate, and a high-speed atomic beam was irradiated before and after irradiation. The film thickness was measured. If the thickness of the silicon thermal oxide film becomes smaller after irradiation with the fast atomic beam, surface contamination or oxide film formation may occur when the surface of the semiconductor substrate to be bonded is treated using the fast atomic beam source. It can be considered possible to remove it. The film thickness was measured using an optical interference film thickness measuring device (Lambda Ace) manufactured by Dainippon Screen Co., Ltd.

The removal efficiency was evaluated by comparing it with a high-speed atomic beam source that does not use a block body (Comparative Example 1, which will be described later), and the evaluation criteria were as follows. If the evaluation results were A, B, or C, it was evaluated that the high-speed atomic beam source could be applied to the production of bonded substrates.
A: The film thickness change before and after irradiation is the same as when no block body is used, and the removal efficiency is the same.
B: The decrease in film thickness after irradiation is slightly smaller than in the case where no block is used, and a slight decrease in removal efficiency is observed, but there is almost no effect on manufacturing efficiency.
C: Compared to the case where no block body is used, the film thickness decreases less after irradiation and the removal efficiency decreases, but the increase in surface treatment time can be considered to have little effect on manufacturing efficiency.
D: The removal efficiency is greatly reduced, the surface treatment time is too long, and the impact on manufacturing efficiency is unacceptable.

Next, the irradiation was repeated intermittently for 30 minutes and paused until the cumulative usage time (integrated value of irradiation time only) reached 20 hours, and then the unused first semiconductor substrate and the second A semiconductor substrate was placed and irradiated with a high-speed atomic beam for 300 seconds. The number of particles on the first semiconductor substrate after irradiation for 300 seconds was measured, and this was defined as the "number of particles after 20 hours of use." Then, 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 calculated. It was evaluated that when this increase ratio was 10 times or less, the release of particle deposits was sufficiently suppressed and the occurrence of major defects in bonding was extremely low. As a result of the irradiation test in Example 1, the rate of increase in the number of particles was doubled. Furthermore, when the removal efficiency was evaluated by measuring the film thickness before and after irradiation for 300 seconds, it was found to be equivalent to the case where no block body was used (evaluation A). The above results are shown in Table 1.

Furthermore, a contact process and a heat treatment process were performed using the first semiconductor substrate and the second semiconductor substrate, which had been subjected to an irradiation process using a high-speed atomic beam source after being used for 20 hours, to produce a bonded substrate. As a result, no bonding inhibition occurred, and a bonded substrate was obtained that was normally bonded.

[Example 2]
Next, Example 2 was conducted. As a fast atomic beam source, a fast atomic beam source 500B (FIG. 7) in which a block body 300B having a triangular pyramidal block body 305 was attached to the corner of the cathode was used. Further, the volume ratio of the block body is 1.0%, W/W0 is 0.76 to 1.0, L/L0 is 0.83 to 1.0, and H/H0 is 0.82 to 1.0. It was 0. An irradiation test was conducted in the same manner as in Example 1 except for the cathode. As a result of calculating the increase rate of the number of particles from the initial state, the increase rate was 8.9 times. When the removal efficiency was evaluated, it was equivalent to the case without using the block body (evaluation A). Furthermore, as a result of manufacturing the bonded substrate, no bonding inhibition occurred and a bonded substrate was obtained that was normally bonded.

[Example 3]
Next, Example 3 was conducted. As a high-speed atomic beam source, a high-speed atomic beam source 500C (FIG. 8) in which block bodies 300C were attached to the corners and sides of the cathode was used. The block body 300C includes triangular prism-shaped blocks 307, 308, and 309 attached to the sides, and a block body in which the four vertices of a triangular pyramid are cut to fit the triangular faces of the block bodies 307, 308, and 309. 306. Further, the volume ratio of the block body is 9.6%, W/W0 is 0.58-0.86, L/L0 is 0.70-0.90, and H/H0 is 0.68-0. It was 90. An irradiation test was conducted in the same manner as in Example 1 except for the cathode. As a result of calculating the increase rate of the number of particles from the initial state, the increase rate was 2.9 times. When the removal efficiency was evaluated, a slight decrease in removal efficiency was observed, but there was almost no effect on manufacturing efficiency (evaluation B). Furthermore, as a result of manufacturing the bonded substrate, no bonding inhibition occurred and a bonded substrate was obtained that was normally bonded.

[Example 4]
Next, Example 4 was conducted. As a high-speed atomic beam source, a high-speed atomic beam source 500D (FIG. 9) in which block bodies 300D were attached to the corners and sides of the cathode was used. The block body 300D includes triangular prism-shaped blocks 311, 312, and 313 attached to the sides, and a block body in which the four vertices of a triangular pyramid are cut to fit the triangular surfaces of the block bodies 311, 312, and 313. 310. Further, the volume ratio of the block body is 14.6%, W/W0 is 0.46-0.86, L/L0 is 0.61-0.90, and H/H0 is 0.59-0. It was 90. An irradiation test was conducted in the same manner as in Example 1 except for the cathode. As a result of calculating the increase ratio of the number of particles from the initial state, the increase ratio was 1.9 times. When the removal efficiency was evaluated, a decrease in removal efficiency was observed, but the effect on manufacturing efficiency due to the increase in surface treatment time was considered to be small (evaluation C). Furthermore, as a result of manufacturing the bonded substrate, no bonding inhibition occurred and a bonded substrate was obtained that was normally bonded.

[Comparative example 1]
Next, Comparative Example 1 was conducted. An irradiation test was conducted 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. As a result of calculating the increase rate of the number of particles from the initial state, the increase rate was 20 times. Further, as a result of manufacturing the bonded substrate, bonding inhibition occurred, and fractured portions were observed in the obtained bonded substrate.

[Comparative example 2]
Next, Comparative Example 2 was conducted. As a fast atomic beam source, a fast atomic beam source 500E (FIG. 10) having a block 300E attached to the corner of the cathode was used. The block body 300E has a triangular pyramid-shaped block body 314. Further, the volume ratio of the block body is 0.4%, W/W0 is 0.83 to 1.0, L/L0 is 0.88 to 1.0, and H/H0 is 0.87 to 1.0. It was 0. An irradiation test was conducted in the same manner as in Example 1 except for the cathode. As a result of calculating the increase rate of the number of particles from the initial state, the increase rate was 12 times. When the removal efficiency was evaluated, it was equivalent to the case without using the block body (evaluation A). Further, as a result of manufacturing the bonded substrate, bonding inhibition occurred, and fractured portions were observed in the obtained bonded substrate.

[Comparative example 3]
Next, Comparative Example 3 was conducted. As a fast atomic beam source, a fast atomic beam source 500F (FIG. 11) in which a block body 300F was attached to the cathode was used. The block body 300F has a block body 315 obtained by cutting two of the vertices of a triangular pyramidal block. Further, the volume ratio of the block body is 23.2%, W/W0 is 0.32-1.0, L/L0 is 0.54-0.84, and H/H0 is 0.49-0. It was 90. An irradiation test was conducted in the same manner as in Example 1 except for the cathode. As a result of calculating the increase ratio of the number of particles from the initial state, the increase ratio was 1.9 times. When the removal efficiency was evaluated, the reduction in removal efficiency was large, the surface treatment time became too long, and the impact on manufacturing efficiency was at an unacceptable level (rating D). Furthermore, as a result of manufacturing the bonded substrate, no bonding inhibition occurred and a bonded substrate was obtained that was normally bonded. However, since the removal efficiency was significantly reduced, it was evaluated that it would be difficult to apply it to the production of bonded substrates.

In Examples 1 to 4, which are exemplary embodiments of the present invention, the release of particle deposits is suppressed by attaching a block body to a region of the cathode member where particles generated by a sputtering phenomenon tend to accumulate. It was shown that the adhesion of particles on the surface to be bonded of the semiconductor substrates irradiated with the high-speed atomic beam was suppressed. In addition, the increase rate of the number of particles is 10 times or less, the release of particle deposits is sufficiently suppressed, and the occurrence of bonding inhibition when bonding semiconductor substrates is suppressed, increasing the manufacturing efficiency of bonded substrates. It has been shown that it is possible. Further, as in Examples 1 to 4, if the volume ratio of the block body is in the range of 1% to 15%, emission of particle deposits can be suppressed and surface contamination on the surface of the semiconductor substrate to be bonded can be suppressed. It was shown that the fast atomic beam source can be applied to the manufacturing of bonded substrates without reducing the removal efficiency of the oxide film or oxide film.

100 Cathode 101 Particle beam discharge port 102 Inert gas inlet 103 Cathode member 103a Corner portion 103b Side 110 Bottom surface 120 Top surface 130 Side surface 140 Side surface 150 Side surface 160 Side surface 200 Anode 300 Block body 301A1 Exposed surface 400 Adhesive material 500 High-speed atomic beam ray Source 700 Bonding substrate 710 First semiconductor substrate 720 Second semiconductor substrate 711, 721 Surface to be bonded

Claims (15)

A cathode of a fast atomic beam source,
The cathode has a box shape with six inner surfaces and is hollow inside,
The six inner surfaces include a bottom surface, a top surface facing the bottom surface and parallel to the bottom surface, and four side surfaces connecting the bottom surface and the top surface. It is composed of a flat cathode member of
The four side surfaces are opposite to each other and are parallel to each other,
Of the four side surfaces, one of the two pairs of opposing side surfaces is provided with an inert gas inlet for introducing an inert gas into the cathode, and the other is provided with an inert gas inlet for introducing an inert gas into the cathode. is equipped with a particle beam emission port that emits a high-speed atomic beam.
The cathode member has a shape whose outline is composed of four corner parts and four sides connecting the corner parts,
In the plane of the cathode member constituting the inner surface of the cathode, the block body has a block body attachment area where the block body is attached via an adhesive material,
The block body pasting area is an area where the amount of re-deposition of sputtered dust generated by the sputtering is larger than the amount of the cathode member removed by sputtering generated by using the high-speed atomic beam source,
The cathode, wherein the volume of the block body is 1% to 15% by volume of the internal volume of the cathode. The cathode according to claim 1, wherein the block body attachment area includes the corner portion. The cathode according to claim 2, wherein the block attachment area further includes the side. On the upper surface,
The ratio of the shortest distance W1 between the block bodies provided at the two corner parts connected by the first diagonal line to the length W0 of a first diagonal line that is a diagonal line connecting the two corner parts of the upper surface. The cathode according to claim 2 or 3, wherein (W1/W0) is 0.4 or more. In the side surface where the inert gas inlet and the particle beam outlet are not provided,
The ratio of the shortest distance L1 between the block bodies provided at the two corner parts connected by the second diagonal line to the length L0 of a second diagonal line that is a diagonal line connecting the two corner parts of the side surface. The cathode according to any one of claims 2 to 4, wherein (L1/L0) is 0.5 or more. In the side surface where the inert gas inlet is provided,
The ratio of the shortest distance H1 between the block bodies provided at the two corner parts connected by the third diagonal line to the length H0 of a third diagonal line that is a diagonal line connecting the two corner parts of the side surface. The cathode according to any one of claims 2 to 5, wherein (H1/H0) is 0.5 or more. 7. The cathode according to claim 2, wherein the exposed surface of the block provided at the corner is a substantially hemispherical concave surface toward the corner. The cathode according to any one of claims 1 to 7, wherein the block body is made of graphite, glassy carbon, silicon, or silicon carbide. The cathode according to any one of claims 1 to 8, wherein the cathode member is made of graphite, glassy carbon, silicon, or silicon carbide. A cathode according to any one of claims 1 to 9,
A high-speed atomic beam source, comprising: an anode provided inside the cathode. A method for manufacturing a bonded substrate in which a first semiconductor substrate and a second semiconductor substrate are stacked, the method comprising:
An irradiation step of irradiating a surface to be bonded of the first semiconductor substrate and a surface to be bonded of the second semiconductor substrate with a high-speed atomic beam in a vacuum using the high-speed atomic beam source according to claim 10. and,
a contact step of contacting the surface to be bonded of the first semiconductor substrate and the surface to be bonded of the second semiconductor substrate irradiated with the high-speed atomic beam to obtain a laminate having a bonding interface;
A method for manufacturing a bonded substrate, comprising: The method for manufacturing a bonded substrate according to claim 11, further comprising a heat treatment step of heat-treating the laminate obtained in the bonding step to obtain a bonded substrate. 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, The method for manufacturing a bonded substrate according to claim 11 or 12. The method for manufacturing a bonded substrate according to any one of claims 11 to 13, wherein the high-speed atomic beam contains any one of argon, neon, and xenon. A method for regenerating the cathode according to any one of claims 1 to 9, comprising:
a block body removal step of removing the block body from the block body pasting area of the cathode member constituting the cathode after being used in a high-speed atomic beam source;
A method for recycling a cathode, comprising the step of pasting a new block body on the block body pasting area of the cathode member from which the block body has been removed.

Images