JP6103919B2 - High-speed atomic beam source, room-temperature bonding apparatus, and room-temperature bonding method - Google Patents

Description

  The present invention relates to a fast atom beam source, a room temperature bonding apparatus, and a room temperature bonding method, and in particular, a room temperature bonding for bonding a plurality of substrates by bringing the activated surface into contact with a fast atom beam source that activates the surface of the substrate. The present invention relates to an apparatus and a room temperature bonding method.

  A MEMS (Micro Electro Mechanical Systems) in which fine electrical parts and mechanical parts are integrated is known. Examples of the MEMS include a micromachine, a pressure sensor, and a micro motor. 2. Description of the Related Art A semiconductor device manufactured by stacking LSI (Large Scale Integration) formed on a semiconductor wafer is known. Such a semiconductor device can reduce an increase in leakage current and a signal delay in wiring.

  Room temperature bonding is known in which wafer surfaces activated in a vacuum atmosphere are brought into contact with each other and bonded to each other. Such room temperature bonding is suitable for producing the MEMS, and is suitable for producing a semiconductor device. The MEMS and the semiconductor device are desired to increase productivity and reduce cost. Therefore, it is desired that the MEMS and the semiconductor device be manufactured from a semiconductor wafer having a large diameter (for example, 12 inches). Therefore, a room-temperature bonding apparatus that can bond a large-diameter semiconductor wafer more appropriately at room temperature is desired.

  As a related technique, Japanese Patent No. 2794429 discloses a silicon wafer bonding method. The silicon wafer bonding method has a large bonding strength and does not require pressing by a load or heat treatment. The silicon wafer room temperature bonding method is a method of bonding silicon wafers to each other, and the bonding surfaces of both silicon wafers are inert gas ion beam or inert gas high speed in vacuum at room temperature prior to bonding. It is characterized by sputter etching by irradiation with an atomic beam. In this method, the wafer surface before bonding is activated from one direction with respect to one wafer.

  Japanese Patent No. 4996044 discloses a bonding apparatus and a bonding method. This bonding apparatus bonds two wafers. This bonding apparatus includes a planarization device, an activation device, and a transfer device. The planarization apparatus planarizes the bonding surfaces of the two wafers. The activation device activates the planarized bonding surface. The transfer device transfers the wafer from the planarization device to the activation device in an atmosphere that suppresses oxidation of the bonding surface. In this apparatus, the wafer surface before the bonding is activated from one direction with respect to one wafer.

  Japanese Patent No. 3970304 discloses a room temperature bonding apparatus. The room temperature bonding apparatus includes a bonding chamber, an upper stage, a carriage, an elastic guide, a positioning stage, a first mechanism, a second mechanism, and a carriage support. The bonding chamber generates a vacuum atmosphere for room-temperature bonding of the upper substrate and the lower substrate. The upper stage is installed inside the bonding chamber and supports the upper substrate in the vacuum atmosphere. A carriage is installed inside the bonding chamber and supports the lower substrate in the vacuum atmosphere. The elastic guide is joined to the carriage in the same body. The positioning stage is installed inside the bonding chamber and supports the elastic guide so as to be movable in the horizontal direction. The first mechanism drives the elastic guide to move the carriage in the horizontal direction. The second mechanism moves the upper stage in a vertical direction that is perpendicular to the horizontal direction. A carriage support is installed inside the bonding chamber, and supports the carriage in a direction in which the upper stage moves when the lower substrate and the upper substrate are pressed against each other. The elastic guide supports the carriage so that the carriage does not contact the carriage support when the lower substrate and the upper substrate do not contact each other. The elastic guide is elastically deformed so that the carriage contacts the carriage support when the lower substrate and the upper substrate are pressed against each other. In this apparatus, as activation of the substrate (wafer) surface before bonding, activation is performed from one direction with respect to two substrates.

  Japanese Patent No. 4172806 (US2010000663 (A1)) discloses a room temperature bonding method and a room temperature bonding apparatus. In this room temperature bonding method, a plurality of substrates are bonded at room temperature via an intermediate material. The room temperature bonding method includes a step of physically sputtering a plurality of targets to form the intermediate material on the bonded surface of the substrate, and a step of activating the bonded surface of the substrate by physical sputtering. It is characterized by including. In this apparatus, as activation of the substrate (wafer) surface before bonding, activation is performed from one direction with respect to two substrates.

  One of the techniques required to enable the room temperature bonding apparatus to be used with a large-diameter wafer is a technique for uniformly activating the entire wafer surface. In the room-temperature bonding apparatus and the room-temperature bonding method described above, whether one or two wafers are etched by beam irradiation from one direction with one surface activation source as activation of the wafer (substrate) surface before bonding. Alternatively, two substrates are etched by beam irradiation from one direction with two surface activation sources. However, as the diameter of the wafer increases, it becomes difficult to etch the wafer surface uniformly and sufficiently with the above-described apparatus and method. Although a method of enlarging the apparatus is conceivable, in order to etch the wafer surface uniformly and sufficiently, there is a problem that the apparatus needs to be very large and is very expensive. There is a demand for a room temperature bonding apparatus that can bond a large-diameter wafer at room temperature and is more compact.

Japanese Patent No. 2791429 Japanese Patent No. 4996044 Japanese Patent No. 3970304 Japanese Patent No. 4172806

  An object of the present invention is to provide a high-speed atomic beam source, a room temperature bonding apparatus, and a room temperature bonding method for more appropriately bonding a plurality of large-diameter substrates. Another object of the present invention is to provide a more compact high-speed atomic beam source, room temperature bonding apparatus, and room temperature bonding method for bonding a plurality of large-diameter substrates. Still another object of the present invention is to provide a high-speed atomic beam source for more uniformly and sufficiently activating the surface of a large-diameter substrate, a room-temperature bonding apparatus and room-temperature bonding for bonding a plurality of large-diameter substrates more uniformly and sufficiently. It is to provide a method.

  In the following, means for solving the problems will be described using the reference numerals used in the modes and examples for carrying out the invention in parentheses. This symbol is added to clarify the correspondence between the description of the claims and the description of the modes and embodiments for carrying out the invention. Do not use to interpret the technical scope.

The fast atom beam source according to the present invention includes a housing (20) and an electrode body (21). The housing (20) has a ring shape and includes a plurality of irradiation hole portions (22) arranged at equal intervals or continuously on the inner surface (20p) of the ring. The electrode body (21) is provided inside the housing (20) and extends along the circumference of the ring. The housing (20) and the electrode body (21) are configured as a cathode and an anode for generating a saddle field type electric field inside the housing (20), respectively. The inner surface of the ring in each of the plurality of irradiation holes (22) faces the center axis (D) of the ring.
In such a fast atom beam source, an activation beam accelerated by a saddle field type electric field is emitted from a plurality of irradiation holes (22) toward the center axis of the ring. Therefore, such a fast atom beam source is activated on the surface of the large-diameter wafer when the large-diameter wafer is set so that the center of the wafer comes on the central axis of the housing (20) (ring). The beam can be irradiated uniformly and sufficiently from the plurality of irradiation holes (22). Thereby, the surface of the large-diameter wafer can be activated more uniformly and sufficiently. However, the inner diameter of the housing (20) (ring) is larger than the diameter of the large-diameter wafer. Such a fast atom beam source has a ring shape in which the casing (20) that emits the activation beam surrounds the large-diameter wafer, so that the size of the case is larger than that of the large-diameter wafer. Can be accommodated. Thereby, the size of the fast atom beam source can be made compact.

In the above fast atom beam source, a plurality of irradiation axes (B) as normals to the inner surface of the ring in the plurality of irradiation holes (22) may intersect at one point on the center axis (D) of the ring. preferable.
In such a fast atom beam source, when a large-diameter wafer is placed so that the center of the wafer comes to the center of the housing (20) (ring), the plurality of irradiation holes (22) are formed at the center of the wafer. Is located on a concentric circumference. The irradiation axes (B) of the plurality of irradiation holes (22) are incident on the surface of the wafer to be activated with a certain angle (α). Therefore, such a fast atom beam source can irradiate the surface of the large-diameter wafer with the activation beam more uniformly and sufficiently from the plurality of irradiation holes (22). Thereby, the surface of the large-diameter wafer can be activated even more uniformly and sufficiently.

In the above fast atom beam source, the housing (20) preferably includes a plurality of partial housings (20-1 to 20-4) having a circular arc shape obtained by dividing the ring. In that case, the electrode body (21) includes a plurality of electrode bodies (21-1 to 21-4) provided inside the plurality of partial housings (20-1 to 20-4) and extending along the arc. It is preferable.
In such a fast atom beam source, the direction (X, Y, Z, θ) of the plurality of irradiation holes (22) of the partial housing (20-i) can be easily changed, and the change width is increased. Can do. That is, the direction of the activation beam can be easily changed, and the change width can be increased. This makes it possible to adjust the angle of incidence (α) of the beam irradiation axis (B) with respect to the wafer and the adjustment of the position coordinates of the point where the beam and the wafer intersect. This means that the distance from the center point (24) of the hole (22) to the point where the beam and the wafer intersect can be adjusted. Therefore, the surface of a large-diameter wafer (substrate) can be more easily and uniformly activated. Further, such a fast atom beam source is easier to manufacture than a ring-shaped housing because the partial housing (20-i) has an arc shape, and is suitable for mass production. Note that the center point (24) of the irradiation hole portion (22) refers to the whole hole as a single opening group when a plurality of openings for emitting a beam are gathered in the irradiation hole portion (22). , And its apparent geometric center point.

In the above fast atom beam source, the anode electrode body (21) is preferably two electrode rods (21) extending along the circumference of the ring and arranged in parallel vertically.
Such a fast atom beam source can stably generate a saddle field type electric field. As a result, the surface of a large-diameter wafer (substrate) can be activated more uniformly and sufficiently.

In the above fast atom beam source, each of the plurality of partial housings (20-1 to 20-4) has an inner surface of the ring circumscribing a circle (L) centered on the central axis (D) of the ring. It may be formed by a plurality of planes (20 ps).
Such a fast atom beam source can be formed more easily than a curved surface because the inner surface of the ring can be formed by continuously joining flat surfaces. In this case, the outer surface of the ring may be formed by continuously joining flat surfaces, or may be formed using a curved surface.

In the above fast atom beam source, each of the plurality of partial housings (20-1 to 20-4) may include a plurality of box-shaped housings (20-ij). In that case, it is preferable that the plurality of box-shaped housings (20-1j to 20-4j) are arranged side by side so as to circumscribe a circle (L) centered on the central axis (D).
Such a fast atom beam source is easier to manufacture than the other cases because the partial housing (20-i) can be formed by combining planes.

In the above fast atom beam source, each of the plurality of irradiation holes may have a horizontally long shape along the circumference of the ring.
Such a fast atom beam source irradiates the wafer with an activation beam from the surroundings, so that the surface of a large-diameter wafer can be activated more uniformly and sufficiently.

The room temperature bonding apparatus of the present invention includes a first fast atom beam source (18), a second fast atom beam source (17), and a pressure welding mechanism (15). The first fast atom beam source (18) emits a plurality of first activation beams irradiated on the first surface of the first substrate. The second fast atom beam source (17) emits a plurality of second activation beams irradiated on the second surface of the second substrate. The pressure contact mechanism (15) joins the first substrate and the second substrate by bringing the first activated surface and the second activated surface into contact with each other after the first surface and the second surface are irradiated. . The first fast atom beam source (18) includes the fast atom beam source described in any of the above paragraphs. The plurality of first activation beams are emitted from the plurality of irradiation holes (22). The center axis (D) of the ring overlaps the center of the first substrate. The second fast atom beam source (17) includes the fast atom beam source described in any of the above paragraphs. The plurality of second activation beams are irradiated from the plurality of irradiation holes (22). The center axis (D) of the ring overlaps the center of the second substrate.
In such a room temperature bonding apparatus, the first and second activation beams accelerated by the saddle field type electric field are emitted from the plurality of irradiation holes (22) of the fast atom beam source described in any of the above paragraphs. , And emitted to the upper and lower large-diameter wafers. Therefore, such a room temperature bonding apparatus can activate the surfaces of the upper and lower large-diameter wafers more uniformly and sufficiently. As a result, the upper and lower large-diameter wafers can be bonded more appropriately. In addition, since such a room temperature bonding apparatus uses the fast atom beam source described in any of the above paragraphs, the overall size of the apparatus including the fast atom beam source can be made compact.

The room temperature bonding apparatus preferably further includes a plurality of position adjusting mechanisms (31) corresponding to the first fast atom beam source (18) and the second fast atom beam source (17). In this case, the position adjusting mechanism (31) corresponding to the first fast atom beam source (18) among the plurality of position adjusting mechanisms is configured to connect the first fast atom beam source (18) to the plurality of irradiation hole portions (22). Are directed to the first substrate such that the plurality of normals (B) intersect the first activation surface at a predetermined first angle. Further, the position adjusting mechanism (31) corresponding to the second fast atom beam source (17) among the plurality of position adjusting mechanisms is configured to connect the second fast atom beam source (17) to the plurality of irradiation hole portions (22). A plurality of normals (B) are directed to the second substrate so that they intersect the second activation surface at a predetermined second angle.
Such a room temperature bonding apparatus can adjust the direction of the first fast atom beam source (18) and the second fast atom beam source (17) to a desired direction. Thereby, the surfaces of the upper and lower large-diameter wafers can be activated more uniformly and sufficiently, respectively. As a result, the upper and lower large-diameter wafers can be bonded more appropriately.
Further, the room temperature bonding apparatus includes a plurality of partial cases (20-1 to 20) in which the case (20) has a circular arc shape obtained by dividing a ring in the high-speed atomic beam source (17) (18). -4). By providing the position adjusting mechanism (31) for each of the plurality of partial housings, the incident angle (α) of the beam irradiation axis (B) with respect to the wafer and the position coordinates of the point where the beam and the wafer intersect, Together, the distance from the center (24) of the beam irradiation hole (22) to the point where the beam and the wafer intersect can be adjusted.
Such a room-temperature bonding apparatus can adjust the first fast atom beam source (18) and the second fast atom beam source (17) to desired directions and positions more easily. Thereby, the surfaces of the upper and lower large-diameter wafers can be more easily and uniformly activated, respectively. As a result, the upper and lower large-diameter wafers can be bonded more appropriately.

In the above room temperature bonding apparatus, the plurality of normal lines (B) of the plurality of irradiation holes (22) of the first fast atom beam source (18) and the first activated surface intersect in the vicinity of the center of the first substrate. May be. The plurality of normal lines (B) of the plurality of irradiation holes (22) of the second fast atom beam source (17) and the second activated surface may intersect in the vicinity of the center of the second substrate.
Such a room-temperature bonding apparatus is capable of suppressing the beam sputtering effect from reaching the metal member located on the outer periphery of the wafer, so that the surfaces of the upper and lower large-diameter wafers can be more reliably, more uniformly and It can be fully activated. As a result, the upper and lower large-diameter wafers can be bonded more appropriately.

In the above room temperature bonding apparatus, the first fast atom beam source (18) and the second fast atom beam source (17) are the housing (20), and a plurality of partial housings having a circular arc shape obtained by dividing the ring When (20-1 to 20-4) are provided, the first fast atom beam source (18) and the second fast atom beam source (17) may be integrated. In that case, a plurality of position adjusting mechanisms (31) corresponding to the single fast atom beam source (19) as the integrated fast atom beam source are further provided. The plurality of position adjusting mechanisms (31) are configured so that a single fast atom beam source (19) is arranged such that a plurality of normals (B) of the plurality of irradiation holes (22) are at a predetermined first angle with the first activation surface Direct to the first substrate to cross. A single fast atom beam source (19) is directed to the second substrate such that the plurality of normals (B) of the plurality of irradiation holes (22) intersect the second activation surface at a predetermined second angle.
Such a room temperature bonding apparatus can relatively reduce the number of fast atom beam sources and position adjusting mechanisms. Thereby, the size of the room temperature bonding apparatus can be further reduced.

In the above room temperature bonding apparatus, the first fast atom beam source (18) and the second fast atom beam source (17) have a plurality of irradiation holes (22) as the first fast atom beam source (18) or the second fast atom beam source. It is preferably arranged so as to be line symmetric with respect to the central axis of the atomic beam source (17).
In such a room temperature bonding apparatus, the activation beam is irradiated almost uniformly onto each substrate from each of the plurality of irradiation holes (22). Thereby, the surfaces of the upper and lower large-diameter wafers can be more uniformly and sufficiently activated. As a result, the upper and lower large-diameter wafers can be bonded more appropriately.

In the above room temperature bonding apparatus, each of the first fast atom beam source (18) and the second fast atom beam source (17) has a plurality of irradiation holes (22) approximately 20 on the inner circumference of the ring. It is preferable to have a shape in which one or more pieces are arranged or the irradiation holes are continuously formed.
Such a room temperature bonding apparatus irradiates the wafer with an activation beam from approximately 20 or more directions, so that the surfaces of the upper and lower large-diameter wafers are more reliably, more uniformly and sufficiently activated. can do. As a result, the upper and lower large-diameter wafers can be bonded more appropriately.

The fast atom beam source of the present invention includes a partial housing (20-i) having an arc shape as one of the plurality of partial housings (20-1 to 20-4) in the above-described fast atom beam source. It is preferable to include.
In such a fast atom beam source, the direction (X, Y, Z, θ) of the plurality of irradiation holes (22) of the partial housing (20-i) can be easily changed, and the change width is increased. Can do. That is, the direction of the activation beam can be easily changed, and the change width can be increased. Then, by combining a plurality of them and incorporating them in the room temperature bonding apparatus, the surface of a large-diameter wafer (substrate) can be more easily and uniformly activated.

The room temperature bonding method according to the present invention is a room temperature bonding method using the room temperature bonding apparatus according to any one of the above paragraphs. The room temperature bonding method includes at least three steps. The first step is a step of irradiating the first activation surface of the first substrate with a plurality of first activation beams, respectively, with the first fast atom beam source (18). The second step is a step of irradiating the second activation surface of the second substrate with a plurality of second activation beams by the second fast atom beam source (17). In the third step, the first activated surface and the second activated surface are brought into contact with each other after the first activated surface and the second activated surface are irradiated by the pressure contact mechanism (15), This is a step of bonding the first substrate and the second substrate.
Since such a room temperature bonding method uses the room temperature bonding apparatus described in any of the above paragraphs, the surfaces of the upper and lower large-diameter wafers can be more uniformly and sufficiently activated, respectively. . As a result, the upper and lower large-diameter wafers can be bonded more appropriately. Such a room temperature bonding method can be carried out in a compact manner because the room temperature bonding apparatus described in any of the above paragraphs is used.

  The present invention can provide a high-speed atomic beam source, a room temperature bonding apparatus, and a room temperature bonding method for more appropriately bonding a plurality of large-diameter substrates. A more compact high-speed atomic beam source, room temperature bonding apparatus and room temperature bonding method for bonding a plurality of large-diameter substrates can be provided. A high-speed atomic beam source that activates the surface of a large-diameter substrate more uniformly and sufficiently, and a room-temperature bonding apparatus and a room-temperature bonding method for bonding a plurality of large-diameter substrates more uniformly and sufficiently can be provided.

FIG. 1 is an XY cross-sectional view schematically showing a configuration of a room temperature bonding apparatus according to an embodiment. FIG. 2 is a YZ sectional view schematically showing the configuration of the room temperature bonding apparatus according to the embodiment. FIG. 3 is a block diagram schematically showing the configuration of the gas type switching mechanism according to the first embodiment. FIG. 4A is a perspective view schematically showing the fast atom beam source according to the first embodiment. FIG. 4B is a perspective view schematically showing the shape of the irradiation hole portion of the fast atom beam source according to the first embodiment. FIG. 4C is a perspective view schematically showing the shape of the irradiation hole portion of the fast atom beam source according to the first embodiment. FIG. 5 is a perspective view schematically showing the fast atom beam source according to the first embodiment. FIG. 6 is a block diagram illustrating a room temperature bonding apparatus control device of the room temperature bonding apparatus according to the embodiment. FIG. 7 is a flowchart showing the room temperature bonding method according to the embodiment. FIG. 8A is a distribution diagram and a graph showing the distribution of the etching rate of the wafer activated by the room temperature bonding apparatus according to the first embodiment. FIG. 8B is a distribution diagram and a graph showing the distribution of the etching rate of the wafer activated by the room temperature bonding apparatus according to the first embodiment. FIG. 9 is a distribution diagram and a graph showing the distribution of the etching rate of the wafer activated by the room temperature bonding apparatus according to the first embodiment. FIG. 10 is a distribution diagram and a graph showing the distribution of the etching rate of the wafer activated by the room temperature bonding apparatus according to the comparative example. FIG. 11A is a perspective view schematically showing a fast atom beam source according to the second embodiment. FIG. 11B is a perspective view schematically showing the shape of the irradiation hole portion of the fast atom beam source according to the second embodiment. FIG. 11C is a perspective view schematically showing the shape of the irradiation hole portion of the fast atom beam source according to the second embodiment. FIG. 12 is a perspective view schematically showing a fast atom beam source according to the third embodiment. FIG. 13A is a plan view schematically showing the configuration of the fast atom beam source according to the second and third embodiments. FIG. 13B is a plan view schematically showing the configuration of the fast atom beam source according to the fourth embodiment. FIG. 13C is a plan view schematically showing another configuration of the fast atom beam source according to the fourth exemplary embodiment.

  A fast atom beam source, a room temperature bonding apparatus, and a room temperature bonding method according to an embodiment of the present invention will be described.

(First embodiment)
The fast atom beam source, room temperature bonding apparatus, and room temperature bonding method according to the first embodiment will be described. 1 and 2 are an XY sectional view and a YZ sectional view schematically showing the configuration of the room temperature bonding apparatus according to the present embodiment, respectively. The room temperature bonding apparatus 1 includes a load lock chamber 2 and a bonding chamber 3. Both the load lock chamber 2 and the joining chamber 3 are formed in a container that seals the inside from the environment. The room temperature bonding apparatus 1 further includes a gate 5 and a gate valve 6. The gate 5 is interposed between the load lock chamber 2 and the bonding chamber 3, and connects the inside of the bonding chamber 3 and the inside of the load lock chamber 2. The gate valve 6 closes or opens the gate 5 by being controlled by a room temperature bonding apparatus control device (described later) of the room temperature bonding apparatus 1.

  The load lock chamber 2 includes a lid and a vacuum exhaust device (not shown). The lid is operated by a user to close or open an opening connecting the environment and the inside of the load lock chamber 2. The vacuum exhaust device exhausts gas from the inside of the load lock chamber 2 by being controlled by the room temperature bonding apparatus control device when the opening and the gate 5 are closed. Examples of the vacuum exhaust device include a turbo molecular pump, a cryopump, and an oil diffusion pump.

  The load lock chamber 2 further includes a plurality of shelves 7 and a transfer robot 8 inside. A plurality of cartridges are placed on the plurality of shelves 7. The cartridge is formed in a generally disc shape. Examples of the material for forming the cartridge include aluminum, stainless steel, aluminum nitride, silicon, quartz, and glassy carbon. The cartridge is used by placing a wafer thereon. When the gate 5 is opened, the transfer robot 8 is controlled by the room temperature bonding apparatus control device to transfer the cartridges arranged on the plurality of shelves 7 into the bonding chamber 3 or the bonding chamber 3. The cartridges arranged inside are transported to a plurality of shelves 7.

  The bonding chamber 3 includes a lid 9 and a vacuum exhaust device 10. The lid 9 is operated by a user to close or open an opening connecting the environment and the inside of the bonding chamber 3. The vacuum exhaust apparatus 10 exhausts gas from the inside of the bonding chamber 3 by being controlled by the room temperature bonding apparatus control apparatus when the gate 5 is closed. Examples of the vacuum exhaust device 10 include a turbo molecular pump, a cryopump, and an oil diffusion pump.

  The bonding chamber 3 further includes a positioning stage carriage 11 and an alignment mechanism 12. The positioning stage carriage 11 is formed in a plate shape. The positioning stage carriage 11 is disposed inside the bonding chamber 3 and is supported so as to be able to move in parallel in the horizontal direction and to be rotatable around a rotation axis in the vertical direction. The positioning stage carriage 11 holds the wafer w by holding the cartridge on which the wafer w is placed. The alignment mechanism 12 is controlled by the room temperature bonding apparatus controller so that the positioning stage carriage 11 moves in parallel in the horizontal direction, or the positioning stage carriage 11 rotates around the vertical rotation axis. Thus, the positioning stage carriage 11 is moved.

The bonding chamber 3 further includes an electrostatic chuck 14 and a pressure contact mechanism 15.
The electrostatic chuck 14 is disposed inside the bonding chamber 3 and is disposed vertically above the positioning stage carriage 11. The electrostatic chuck 14 is supported by the bonding chamber 3 so as to be movable in the vertical direction. The electrostatic chuck 14 is formed of a dielectric layer that is an insulator exemplified by alumina ceramics. The electrostatic chuck 14 has a flat surface substantially perpendicular to the vertical direction at the lower end. The electrostatic chuck 14 further includes an internal electrode (not shown) disposed inside the dielectric layer. In the electrostatic chuck 14, a predetermined applied voltage is applied to the internal electrode by being controlled by the room temperature bonding apparatus controller. The electrostatic chuck 14 holds the wafer w or the substrate disposed near the flat surface of the dielectric layer with an electrostatic force by applying a predetermined applied voltage to the internal electrode.

  The pressure contact mechanism 15 translates the electrostatic chuck 14 in the vertical direction with respect to the bonding chamber 3 by being controlled by the room temperature bonding apparatus controller. For example, the pressure welding mechanism 15 arranges the electrostatic chuck 14 at one of a plurality of positions by being controlled by the room temperature bonding apparatus controller. The plurality of positions includes an alignment position, a home position, and an activation position. The alignment position is when the lower wafer w is held by the positioning stage carriage 11 and when the upper wafer w is held by the electrostatic chuck 14, the lower wafer w and the upper wafer w Are designed to be separated by a predetermined distance (example: 1 mm). The home position is further vertically above the alignment position. The activation position is further vertically above the home position. The pressure contact mechanism 15 is further controlled by a room temperature bonding apparatus control device to translate the electrostatic chuck 14 in the vertical direction with respect to the bonding chamber 3 so that the upper wafer w is pressed against the lower wafer w. Let The pressure welding mechanism 15 is further controlled by the room temperature bonding apparatus control device to measure the position where the electrostatic chuck 14 is disposed, and outputs the position to the room temperature bonding apparatus control device. The pressure welding mechanism 15 is further controlled by the room temperature bonding apparatus control device, thereby measuring the load applied to the wafer held by the electrostatic chuck 14 and outputting the load to the room temperature bonding apparatus control device.

  The bonding chamber 3 further includes an activation device 16. The activation device 16 includes a lower atom beam source 17, an upper atom beam source 18, and a position adjusting mechanism 31. The lower atom beam source 17 has a ring shape, and is disposed inside the bonding chamber 3 and below the upper atom beam source 18. The lower atom beam source 17 is a fast atom beam source exemplified by a FAB (Fast Atom Beam) source, and irradiates the lower wafer w with a fast atom beam as an activation beam. The upper atom beam source 18 has a ring shape, and is disposed inside the bonding chamber 3 and above the lower atom beam source 17. The upper atom beam source 18 is a fast atom beam source exemplified by an FAB source, and irradiates the upper wafer w with a fast atom beam as an activation beam. However, the lower atom beam source 17 and the upper atom beam source 18 may be ion beam sources. In that case, the lower atomic beam source 17 and the upper atomic beam source 18 irradiate the wafer w with an ion beam as an activation beam. Below, it demonstrates as a fast atom beam source.

  The position adjusting mechanism 31 is provided inside the bonding chamber 3 and holds the lower atom beam source 17 and the upper atom beam source 18 in the bonding chamber 3 so as to be movable. In the example of this figure, the position adjusting mechanism 31a of the position adjusting mechanism 31 is provided at two locations so as to support both ends of the ring of the lower atomic beam source 17 in the diametrical direction. The two position adjusting mechanisms 31a hold the lower atomic beam source 17 so as to be movable in the X, Y, and Z directions in conjunction with each other. Of the position adjusting mechanisms 31, the position adjusting mechanisms 31b are provided at two locations so as to support both ends of the ring of the upper atomic beam source 18 in the diameter direction. The two position adjusting mechanisms 31b interlock with each other to hold the upper atomic beam source 18 so as to be movable in the X direction, the Y direction, and the Z direction.

  The room temperature bonding apparatus 1 further includes a plurality of gas type switching mechanisms corresponding to the lower atom beam source 17 and the upper atom beam source 18. FIG. 3 is a block diagram schematically showing the configuration of the gas type switching mechanism in the room temperature bonding apparatus according to the present embodiment. Since the gas type switching mechanism 61 corresponding to the lower atomic beam source 17 and the upper atomic beam source 18 both have the same structure, in this figure, the gas type switching mechanism corresponding to the lower atomic beam source 17 is used. 61 is shown.

  The gas type switching mechanism 61 corresponding to the lower atom beam source 17 and the upper atom beam source 18 is controlled by the room temperature bonding apparatus controller, so that predetermined gases are respectively supplied to the lower atom beam source 17 and the upper atom beam source 17. Supply to source 18. Specifically, the gas type switching mechanism 61 includes a plurality of gas supply devices 62-1 to 62-4, a plurality of valves 63-1 to 63-4, and a pipe line 64. The plurality of gas supply devices 62-1 to 62-4 are disposed outside the bonding chamber 3. The plurality of gas supply devices 62-1 to 62-4 are formed of, for example, a plurality of cylinders, and each release a plurality of different gases. For example, the gas supply devices 62-1, 62-2, 62-3, and 62-4 release argon gas Ar, neon gas Ne, krypton gas Kr, and xenon gas Xe, respectively. The plurality of valves 63-1 to 63-4 are arranged outside the bonding chamber 3. Arbitrary valves 63-i (i = 1, 2, 3, 4) of the plurality of valves 63-1 to 63-4 are controlled by the room temperature bonding apparatus control device, whereby a plurality of gas supply devices are provided. The gas discharged from 62-i is supplied to the pipe line 64, or the supply of the gas to the pipe line 64 is stopped. The pipe 64 connects the plurality of valves 63-1 to 63-4 to the lower atom beam source 17 or the upper atom beam source 18. At this time, the lower atomic beam source 17 or the upper atomic beam source 18 is controlled by the room temperature bonding apparatus controller, thereby generating a high-speed atomic beam using the gas supplied from the gas type switching mechanism 61 and emitting it. To do.

Next, the fast atom beam source according to the present embodiment will be further described.
The lower atom beam source 17 and the upper atom beam source 18 as the fast atom beam source have the same structure except that the vertical direction is reversed. Therefore, hereinafter, the lower atom beam source 17 will be described as a fast atom beam source.

  FIG. 4A is a perspective view schematically showing the lower atom beam source 17 as the fast atom beam source according to the present embodiment (note that the upper atom beam source 18 is seen when the up and down directions are reversed. be able to).

  The housing 20 has a ring shape and includes a plurality of irradiation hole portions 22 arranged at equal intervals or continuously on the inner surface 20p of the ring. The electrode body 21 is provided inside the housing 20 and extends along the circumference of the ring of the housing 20. The housing 20 and the electrode body 21 function as a cathode and an anode that generate a saddle field type electric field inside the housing 20, respectively. The inner surface of the ring in each of the plurality of irradiation holes 22 faces the center axis D of the ring. The electrode body 21 is preferably two electrode rods extending along the circumference of the ring and arranged in parallel vertically. Assuming that the normal to the inner side of the ring at the center 24 of the surface of each irradiation hole 22 is the irradiation axis B, the irradiation axis B is the same as the irradiation direction of the fast atom beam irradiated from each irradiation hole 22. . The irradiation axes B of the plurality of irradiation holes 22 intersect at one point of the center axis D of the ring. In other words, the plurality of irradiation holes 22 are arranged symmetrically with respect to the center axis D of the ring. Or the several irradiation hole part 22 is arrange | positioned with respect to the central axis D of a ring in rotational symmetry.

  Here, in the room temperature bonding apparatus 1, the wafer w is arranged so that the center axis D of the ring of the housing 20 and the center C1 of the wafer w intersect. In the example of this figure, the irradiation axes B of the plurality of irradiation holes 22 intersect at one point of the center axis D of the ring, and at the same time, at the center C1 of the lower wafer w. However, the irradiation axes B of the plurality of irradiation holes 22 may intersect with the lower wafer w at the position of the circle C2 in the wafer w with the center axis D of the ring as the center. In other words, at least the intersections between the irradiation axis B and the wafer w are all on the wafer w.

  4B and 4C are perspective views schematically showing the shape of the irradiation hole portion of the fast atom beam source according to the present embodiment. The shape of each irradiation hole portion 22 is not particularly limited, but preferably has a horizontally long shape extending along the circumference of the ring of the housing 20 as will be described later. In FIG. 4B, the horizontally long irradiation hole 22 is shown as an example. Although not shown, the shape of the irradiation hole 22 may be a rectangle with rounded corners or a horizontally long ellipse. In FIG. 4C, as another example, the horizontally long rectangle further extends to show a band-shaped irradiation hole portion 22. In this case, there may be no end.

  FIG. 5 is a perspective view schematically showing a part of the lower atomic beam source 17 shown in FIG. 4A. The housing | casing 20 is equipped with the cathode 20a and the coating | coated part 20b. The cathode 20a has a ring shape, and includes a plurality of irradiation hole portions 22 arranged at equal intervals or continuously on the inner surface of the ring. The irradiation hole 22 is a part of the cathode 20a and is a conductor having a plurality of irradiation holes 23 arranged at equal intervals or continuously. The irradiation hole portion 22 is exemplified by a lattice-like or net-like conductor (grid) or a conductor plate having a plurality of holes opened. The irradiation hole portion 22 may be formed by directly processing the side surface of the cathode 20a, or an opening portion may be provided in the cathode 20a and a separately prepared irradiation hole portion member may be attached. The surface of the irradiation hole portion 22 is a surface formed by the lattice, net, or plate. The shape of the irradiation hole 23 is not particularly limited, such as a circle, an ellipse, a square, or a rectangle. However, similarly to the irradiation hole portion 22, it may have a horizontally long shape extending along the circumference of the ring of the housing 20.

  When the plurality of irradiation holes 23 of the irradiation hole portion 22 are considered as a group of irradiation hole groups, the irradiation hole portion 22 passes through a substantially central point (= center point of the irradiation hole portion 22) 24 of the region of the irradiation hole group. An axis in a direction substantially perpendicular to the surface of the surface is the irradiation axis B described above. The direction of the irradiation axis B can also be regarded as the direction in which the fast atom beam is irradiated. The center points of all irradiation hole groups (center points of all irradiation hole portions 22) 24 are arranged on the circumference of a circle L that is concentric with the center C1 of the wafer w that is the irradiation target (etching target). . In other words, the plurality of irradiation holes 23 of the irradiation hole portion 22 are arranged on or near the circumference of a circle L concentric with the center C1 of the wafer w.

  Further, the two electrode rods as the electrode body 21 are arranged along the circumference of a circle concentric with the center C1 of the wafer w to be irradiated (etching target), similarly to the irradiation hole portion 22 and the irradiation hole 23. They are formed in a ring shape or an arc shape in parallel with each other. The two electrode rods as the electrode body 21 are arranged in the vertical direction in the substantially Z direction in parallel with the surface of the irradiation hole portion 22.

  In the housing 20, the surface of the irradiation hole portion 22 is perpendicular to the vertical direction so that the direction (normal direction) of the surface of the irradiation hole portion 22 faces the wafer w arranged on the lower side of the housing 20. It is inclined by a predetermined angle α. In other words, the direction of the irradiation axis B is inclined by a predetermined angle α with respect to the vertical direction so as to face the lower wafer w. For example, when there is a straight line that is inclined by an angle α with respect to one side of the rectangle, the casing 20 has a rectangular shape on the plane and does not intersect with the rectangular shape. This is realized by taking the shape. Or, for example, when the casing 20 has a rectangle on the plane and a straight line parallel to one side of the rectangle, the shape of the rectangular cross section is obtained when the rectangle is rotated about the straight line. It is realized by making the shape that twists the inside downward while maintaining the above. The housing 20 has a shape in which the inner surface of the rectangular cross section is previously inclined downward.

  With the shape of the casing 20, the two electrode rods as the electrode body 21 have an inclination of a line segment connecting the center of the upper electrode rod and the center of the lower electrode rod by a predetermined angle α. ing. In other words, the diameter of the ring formed by the upper electrode rod is smaller than the diameter of the ring formed by the lower electrode rod. Therefore, all the irradiation axes B are incident on the surface of the wafer w to be activated (etched) with a predetermined angle α.

  The housing 20 further has a gas inlet 20c. The gas inlet 20c is a hole provided on the outer surface 20q of the ring of the housing 20 and penetrating the cathode 20a and the covering portion 20b. The gas inlet 20c introduces the gas supplied from the gas type switching mechanism 61 into the cathode 20a. The covering portion 20b is a casing having the same potential as the cathode 20a covering the outer surface of the cathode 20a excluding the plurality of irradiation hole portions 22.

  The lower atom beam source 17 is controlled by a room temperature bonding apparatus controller, so that a ground voltage and a DC voltage E are applied to the cathode 20a and the electrode body 21, respectively, and a gas (for example, argon ( Ar)). As a result, a saddle field type electric field is generated inside the case 20, the gas introduced into the case 20 is turned into plasma, and the ions are accelerated outward by the electric field. A part of the accelerated ions is combined with electrons generated by ion collision with the inner wall of the housing 20 and the irradiation hole 22 to generate a neutral atom beam (fast atom beam FAB). The neutral atom beam (fast atom beam) is emitted as an activation beam from the plurality of irradiation holes 23 of the plurality of irradiation hole portions 22 along the irradiation axis B in the wafer w direction.

  Next, the room temperature bonding apparatus control device 71 of the room temperature bonding apparatus 1 according to the present embodiment will be described. FIG. 6 is a block diagram showing a room temperature bonding apparatus control device of the room temperature bonding apparatus 1 according to the present embodiment. The room temperature bonding apparatus control device 71 is an information processing apparatus exemplified by a computer, and includes a CPU, a storage device, and an interface not shown. The CPU executes the computer program installed in the room temperature bonding apparatus control device 71 to control the storage device and the interface. The storage device records the computer program and temporarily records information created by the CPU.

  The interface outputs information created by a plurality of external devices connected to the room temperature bonding apparatus control device 71 to the CPU, and outputs information created by the CPU to the plurality of external devices. . Examples of the plurality of external devices include an input device, an output device, a communication device, and a removable memory drive. The communication apparatus is used to download a computer program installed in the room temperature bonding apparatus control apparatus 71 from another computer. The removable memory drive is used to read and install data and computer programs recorded on the recording medium into a storage device when the recording medium is inserted. Examples of the recording medium include a magnetic disk (flexible disk, hard disk), an optical disk (CD, DVD), a magneto-optical disk, and a flash memory.

  The interface further connects each component of the room temperature bonding apparatus 1 to the room temperature bonding apparatus controller 71. Specifically, the interface connects the gate valve 6, the transfer robot 8, and the vacuum exhaust device exhausted from the load lock chamber 2 to the room temperature bonding apparatus control device 71. Further, the interface includes an evacuation apparatus 10, an alignment mechanism 12, an electrostatic chuck 14, a pressure contact mechanism 15, a lower atomic beam source 17, an upper atomic beam source 18, and a plurality of valves 63-1 to 63-4. It is connected to the room temperature bonding apparatus controller 71.

  The computer program installed in the room temperature bonding apparatus control device 71 is formed of a plurality of computer programs for causing the room temperature bonding apparatus control device 71 to realize a plurality of functions. The plurality of functions includes a conveyance unit 72, an activation unit 73, and a bonding unit 74. The transfer unit 72 controls the room temperature bonding apparatus 1 with respect to transfer, installation, and removal of the wafer. Specifically, control of the vacuum evacuation device of the load lock chamber 2, control of opening and closing of the gate valve 6, control of transport of the cartridge by the transport robot 8, control of the press contact mechanism 15, and control of the electrostatic chuck 14 are mainly performed. Do. The activation unit 73 controls the room temperature bonding apparatus 1 with respect to the activation of the wafer. Specifically, control of the vacuum evacuation device 10 of the bonding chamber 3, control of the gas type switching mechanism 61, control of the pressure contact mechanism 15, and control of the upper atom beam source 18 and the lower atom beam source 17 are mainly performed. The bonding unit 74 controls the room temperature bonding apparatus 1 with respect to wafer bonding. Specifically, the control of the press contact mechanism 15, the control of the electrostatic chuck 14, and the alignment mechanism 12 are mainly performed.

  Next, a room temperature bonding method (operation of a room temperature bonding apparatus) according to the first embodiment of the present invention will be described. FIG. 7 is a flowchart showing the room temperature bonding method according to the present embodiment. This room temperature bonding method is performed using the room temperature bonding apparatus 1 described above.

  The conveyance unit 72 of the room temperature bonding apparatus controller 71 first closes the gate 5 by controlling the gate valve 6. When the gate 5 is closed, the transfer unit 72 controls the vacuum exhaust device 10 by controlling the vacuum exhaust device of the load lock chamber 2 by controlling the vacuum exhaust device of the load lock chamber 2 to make the inside of the load lock chamber 2 an atmospheric pressure atmosphere. Then, a bonding atmosphere is generated inside the bonding chamber 3.

  The user prepares a plurality of lower wafers and a plurality of upper wafers, and a plurality of lower cartridges and a plurality of upper cartridges corresponding thereto. The plurality of lower wafers includes a lower wafer w, and the plurality of upper wafers includes an upper wafer w. The user opens the lid of the load lock chamber 2 and arranges the plurality of lower cartridges and the plurality of upper cartridges on the plurality of shelves 7. On the lower cartridge corresponding to the lower wafer w, the lower wafer w is placed so that the back of the activated surface faces the lower cartridge. The upper wafer w is placed on the upper cartridge corresponding to the upper wafer w so that the activation surface faces the upper cartridge. The user then closes the lid of the load lock chamber 2. The transport unit 72 controls the evacuation device to make the interior of the load lock chamber 2 a preliminary atmosphere (step S1).

  The transport unit 72 opens the gate 5 by controlling the gate valve 6. The transfer unit 72 controls the transfer robot 8 to transfer the upper cartridge from the plurality of shelves 7 to the positioning stage carriage 11 so that the upper wafer w is held by the positioning stage carriage 11 of the bonding chamber 3. The conveyance unit 72 lowers the electrostatic chuck 14 by controlling the pressure contact mechanism 15. The transport unit 72 measures the load applied to the electrostatic chuck 14 by controlling the pressure contact mechanism 15. The transport unit 72 calculates the timing at which the load reaches a predetermined contact load based on the change in the load, that is, the timing at which the upper wafer w mounted on the upper cartridge contacts the electrostatic chuck 14. Calculated based on changes in load. The conveyance unit 72 controls the press contact mechanism 15 to stop the lowering of the electrostatic chuck 14 at that timing.

  The transport unit 72 controls the electrostatic chuck 14 to hold the upper wafer w on the electrostatic chuck 14. The transport unit 72 controls the pressure contact mechanism 15 to raise the electrostatic chuck 14 until the electrostatic chuck 14 is disposed at the home position. The transport unit 72 then transports the upper cartridge from the positioning stage carriage 11 to the plurality of shelves 7 by controlling the transport robot 8.

  Thereafter, the transport unit 72 controls the transport robot 8 to move the lower cartridge from the plurality of shelves 7 to the positioning stage carriage 11 so that the lower wafer w is held by the positioning stage carriage 11 of the bonding chamber 3. Transport to. Thereafter, the transport unit 72 controls the gate valve 6 to close the gate 5 (step S2).

  The activation unit 73 of the room temperature bonding apparatus controller 71 controls the pressure contact mechanism 15 to raise the electrostatic chuck 14 until the electrostatic chuck 14 is disposed at the activation position, thereby controlling the vacuum exhaust apparatus 10. By doing so, the activated atmosphere is produced | generated in the inside of the joining chamber 3 (step S3). The activating unit 73 further activates the entire activation surface of the upper wafer w and the entire activation surface of the lower wafer w by controlling the activation device 16 (step S4). That is, the activated surface of the lower wafer w is activated by the fast atom beam irradiated from the lower atom beam source 17. The activated surface of the upper wafer w is activated by a fast atom beam emitted from the upper atom beam source 18.

  Thereafter, the bonding portion 74 of the room temperature bonding apparatus control apparatus 71 controls the pressure welding mechanism 15 to lower the electrostatic chuck 14 and arrange the electrostatic chuck 14 at the alignment position. The bonding unit 74 controls the alignment mechanism 12 to place the lower wafer w at a predetermined alignment position with respect to the upper wafer w (step S5).

  Thereafter, the bonding portion 74 controls the pressure contact mechanism 15 to lower the electrostatic chuck 14. The joint 74 measures the load applied to the electrostatic chuck 14 by controlling the pressure contact mechanism 15. The joining part 74 calculates the timing when the load reaches a predetermined joining load. The bonding portion 74 controls the pressure contact mechanism 15 to stop the lowering of the electrostatic chuck 14 at that timing, that is, applies the bonding load to the upper wafer w and the lower wafer w (step S6). The lower wafer w and the upper wafer w are bonded to each other when a bonding load is applied to form a single bonded wafer.

  Thereafter, the bonding unit 74 controls the electrostatic chuck 14 to release the bonded wafer from the electrostatic chuck 14. Thereafter, the joining portion 74 raises the electrostatic chuck 14 by controlling the pressure contact mechanism 15. Thereafter, the transfer unit 72 controls the gate valve 6 to open the gate 5. The transfer unit 72 controls the transfer robot 8 to transfer the lower cartridge from the positioning stage carriage 11 to the plurality of shelves 7 so that the bonded wafer is transferred to the load lock chamber 2 (step S7). .

  When the other lower cartridge on which the lower wafer is placed and the other upper cartridge on which the upper wafer is placed are arranged on the plurality of shelves 7 (step S8, YES) Steps S2 to S7 are repeated and executed again.

  When the lower wafer and the upper wafer that are scheduled to be bonded are not arranged on the plurality of shelves 7 (step S8, NO), the transfer unit 72 controls the gate valve 6 to control the gate 5 Close. Thereafter, the transfer unit 72 controls the evacuation device of the load lock chamber 2 to bring the inside of the load lock chamber 2 into an atmospheric pressure atmosphere (step S9). Thereafter, the user opens the lid of the load lock chamber 2 and takes out the plurality of lower cartridges and the plurality of upper cartridges from the plurality of shelves 7 to load lock the plurality of bonded wafers including the bonded wafers. Remove from chamber 2.

  When the user wants to further bond another plurality of lower wafers and another plurality of upper wafers at room temperature, the user corresponds to the plurality of lower cartridges corresponding to the plurality of lower wafers and the plurality of upper wafers. A plurality of upper cartridges are prepared, and such a room temperature bonding method is executed again.

  As described above, the operation of the room temperature bonding apparatus according to the present embodiment is performed.

  8A and 8B are a distribution diagram showing the distribution of the etching rate of the wafer activated by the room temperature bonding apparatus according to the present embodiment, and a graph showing a profile in the cross-sectional direction passing through the center of the wafer. This figure shows the distribution of the etching rate in the wafer surface when the lower wafer w is etched by the lower atom beam source 17 (when a plurality of high-speed atom beams are irradiated from the outer periphery in the wafer radial direction). . Further, the lower atom beam source 17 divides the inner surface 20p of the ring of the housing 20 into 36 equal parts, and one irradiation hole portion 22 is provided on each of the 36 surfaces formed by being divided into 36 equal parts. . That is, the same fast atom beam is irradiated from 36 directions.

  In this case, the etching rate changes concentrically, but the change is small and the graph is flat overall. The maximum etching rate is 2.3 nm / min. Near the wafer center. It is. The minimum value of the etching rate is 0.8 nm / min. It is. The etching rate ratio (maximum value / minimum value) is 2.9. That is, the difference between the maximum value and the minimum value is small, and the etching rate distribution is substantially uniform. That is, the distribution of the etching rate can be said to be a sufficiently acceptable range.

  As described above, the high-speed atomic beam is irradiated from the 36 irradiation hole portions 22 over the entire surface of the wafer without deviation, so that the etching rate ratio which is an index of the uniformity of activation can be reduced. As a result, a uniform etching surface can be formed on a large-area (large-diameter) wafer by a high-speed atomic beam irradiated uniformly from the circumferential direction of the wafer.

  At this time, it is considered that the range in which the fast atom beam irradiated from each irradiation hole portion 22 broadly overlaps the shape of the wafer on the wafer surface. Therefore, it is less likely that only the wafer to be etched is intensively etched (sputtered) and parts other than the wafer are etched. As a result, the deposition of impurities on the wafer is prevented. And it can prevent that a particle disperses on a wafer, and joining quality improves.

  FIG. 9 is a distribution diagram and a graph showing the distribution of the etching rate of the wafer activated by the room temperature bonding apparatus according to the present embodiment. In this figure, the lower atomic beam source 17 divides the inner surface 20p of the ring of the housing 20 into 24 equal parts, and one irradiation hole portion 22 is provided on each of the 24 surfaces formed by the 24 equal parts. ing. That is, the same fast atom beam is irradiated from 24 directions. However, the size of the irradiation hole 22 is the same as that in the case of FIG. 8A. Further, geometrical factors such as the beam incident angle α on the wafer, the diameter of the virtual circle C2 connecting the beam irradiation points on the wafer w, and the distance from the irradiation hole center 24 to the point where the irradiation axis B intersects the wafer w. Except for the arrangement, the other beam source irradiation conditions such as applied voltage are the same as in FIG. 8A.

  Although the etching rate changes in a concentric manner, the change is small. However, the change is slightly larger than that in FIG. 8A, and an uneven portion such as a wave at the edge of the wafer is generated. The maximum etching rate is 3.1 nm / min. It is. The minimum value of the etching rate is 1.7 nm / min. It is. The etching rate ratio (maximum value / minimum value) is 1.8. That is, the difference between the maximum value and the minimum value is small, and the etching rate distribution is substantially uniform. Although a non-uniform portion such as a wave at the edge of the wafer is generated, the distribution of the etching rate can be said to be an acceptable range because the non-uniform portion is small.

  FIG. 10 is a distribution diagram and a graph showing the distribution of the etching rate of the wafer activated by the room temperature bonding apparatus according to the comparative example. In this figure, the lower atom beam source 17 divides the inner surface 20p of the ring of the housing 20 into 12 equal parts, and one irradiation hole 22 is formed on each of the 12 surfaces formed by the 12 equal parts. Provided. That is, the same fast atom beam is irradiated from 12 directions. However, the size of the irradiation hole 22 is the same as that in the case of FIG. 8A. Further, geometrical factors such as the beam incident angle α on the wafer, the diameter of the virtual circle C2 connecting the beam irradiation points on the wafer w, and the distance from the irradiation hole center 24 to the point where the irradiation axis B intersects the wafer w. Except for the arrangement, the other beam source irradiation conditions such as applied voltage are the same as in FIG. 8A.

  The etching rate changes substantially concentrically in the vicinity of the center, but a significant non-uniform portion such as undulation occurs in the outer region. The maximum value of the etching rate is 5.4 nm / min. It is. The minimum value of the etching rate is 0.1 nm / min. It is. The etching rate ratio (maximum value / minimum value) is 54. That is, the difference between the maximum value and the minimum value is an order of magnitude greater than that in FIGS. That is, the etching rate largely changes concentrically near the center of the wafer, and a non-uniform portion such as a undulation is generated in the outer region, which is non-uniform as a whole. Therefore, although depending on a preset allowable range, the distribution of the etching rate can be said to be an unacceptable range. Note that the allowable range of the uniformity of the etching rate within the wafer surface is determined according to the use of the joined body from the uniformity of the joining strength of the wafer after joining.

  From the above, in order to uniformly activate the wafer surface, when the lower atom beam source 17 and the upper atom beam source 18 irradiate the same fast atom beam from the plurality of irradiation hole portions 22, a plurality of irradiation holes are irradiated. It is considered preferable to increase the number of the portions 22 to approximately 20 or more (consecutive irradiation hole group). In other words, in order to stably and uniformly activate the wafer surface, when irradiating from a plurality of directions using the same fast atom beam, it is preferable to irradiate from approximately 20 directions or more. It is done. Such a room temperature bonding apparatus can more reliably and more uniformly activate the surfaces of the upper and lower large-diameter wafers (substrates). As a result, the upper and lower large-diameter wafers (substrates) can be bonded more appropriately.

  As described above, in this embodiment, etching without deviation by an activation beam such as a fast atom beam can be performed. Thereby, the large-diameter wafer surface can be brought into a more uniform activated state. As a result, the wafer surface can be made uniform in roughness and cleanliness. And the dispersion | variation in joining strength is suppressed over the whole wafer surface, and joining quality improves.

  Further, in this embodiment, it is less likely to etch (sputter) parts other than the wafer to be activated. That is, parts other than the wafer are sputtered, and the particles do not adhere to the wafer surface and become voids in the bonding surface. Therefore, impurity deposition is prevented, particle scattering can be prevented, and bonding quality is improved.

  The yield of devices formed on the wafer can be improved by the above effects.

(Second Embodiment)
The fast atom beam source, room temperature bonding apparatus, and room temperature bonding method according to the second embodiment will be described. In the first embodiment, a single ring-shaped fast atom beam source is used, but in this embodiment, a plurality of arc-shaped fast atom beam sources obtained by dividing the ring are used. In the following, differences from the first embodiment will be mainly described.

  The fast atom beam source according to the present embodiment will be described. The lower atom beam source 17 and the upper atom beam source 18 as the fast atom beam source have the same structure except that the vertical direction is reversed. Therefore, hereinafter, the lower atom beam source 17 will be described as a fast atom beam source.

  FIG. 11A is a perspective view schematically showing a lower atom beam source 17 as a fast atom beam source according to the present embodiment (note that the upper atom beam source 18 is seen when the up and down directions are reversed. be able to).

  The lower atom beam source (fast atom beam source) 17 according to the present embodiment has an arc shape (divided ring shape) and configuration obtained by dividing the ring-shaped fast atom beam source of the first embodiment. doing. However, the number of divisions is arbitrary. In the following, as an example, a lower atomic beam source 17 having an arc shape obtained by dividing the ring-shaped fast atomic beam source of the first embodiment into four will be described as shown in FIG.

  The lower atom beam source 17 includes lower atom beam sources 17-1, 17-2, 17-3, and 17-4. Each lower atomic beam source 17-k (k = 1 to 4: integer) includes a partial housing 20-k and an electrode body 21-k. The partial housing 20-k has a circular arc shape obtained by dividing the ring, and includes a plurality of irradiation hole portions 22 arranged at equal intervals or continuously on the inner surface 20p of the circular arc. The electrode body 21-k is provided inside the partial housing 20-k and extends along the arc of the ring of the partial housing 20-k. The housing 20-k and the electrode body 21-k function as a cathode and an anode that generate a saddle field type electric field inside the partial housing 20-k, respectively. The electrode body 21 is preferably two electrode rods extending along the arc and arranged in parallel vertically. Assuming that the normal to the inner side of the arc of the ring at the center 24 of the surface of each irradiation hole 22 is the irradiation axis B, the irradiation axes B of the plurality of irradiation holes 22 intersect at one point on the center axis D of the ring. .

  The position adjusting mechanism 31b among the position adjusting mechanisms 31 is provided at one position so as to support the outer side of the arc shape of the lower atomic beam source 17-k, and the lower atomic beam source 17-k is moved in the X direction and Y direction. It can be moved in the direction and the Z direction, and can be rotated so as to have a desired angle θ. In the example of this figure, only the position adjusting mechanism 31b attached to the lower atom beam source 17-2 is shown, but the same applies to the other lower atom beam sources 17-1, 17-3, and 17-4. A position adjusting mechanism 31b is attached to the head. The same applies to the position adjusting mechanism 31a of the upper atomic beam source 18-k in the position adjusting mechanism 31. The lower atom beam source 17-k can be moved in the X, Y, and Z directions, and can be rotated so as to have a desired angle θ, so that the irradiation conditions of the high-speed atom beam can be easily changed. It becomes. Therefore, the wafer w can be more easily and uniformly irradiated with a high-speed atomic beam.

  In the first embodiment, for example, when the housing 20 has a rectangular shape on a plane and a straight line that does not intersect with the rectangular shape and is inclined by an angle α with respect to one side of the rectangular shape, The shape of the rotating body that can be produced when rotating. This is because the direction of the irradiation axis B is inclined by a predetermined angle α with respect to the vertical direction so as to face the lower wafer w. However, in the present embodiment, since the angle θ of the housing 20-k can be set to a desired inclination by the position adjustment mechanism 31, the direction of the irradiation axis B can be set to the desired angle α. Therefore, it is not always necessary to make the inner surface of the arc of the rectangular cross section inclined in advance downward. That is, a shape obtained by dividing a ring having a rectangular cross section as it is can be used as the housing 20-k.

  11B and 11C are perspective views schematically showing the shape of the irradiation hole portion of the fast atom beam source according to the present embodiment. The shape of each irradiation hole portion 22 is not particularly limited, but preferably has a horizontally long shape extending along the circumference of the ring of the housing 20-k as described in the first embodiment. . In FIG. 9B, as an example, a horizontally long irradiation hole 22 is shown. Although not shown, the shape of the irradiation hole 22 may be a rectangle with rounded corners or a horizontally long ellipse. In FIG. 9C, as another example, the horizontally elongated rectangle further extends to show a band-shaped irradiation hole portion 22.

  Here, the number of divisions of the ring-shaped fast atom beam source according to the first embodiment is such that the position adjustment mechanism 31 can easily set the angle θ of the housing 20-k to a desired inclination, or position adjustment. From the viewpoint of ease of installation in the bonding chamber 3 including the mechanism 31, it is preferably 4 to 8. If the number of divisions is too large, installation becomes difficult, and the size of the whole room-temperature bonding apparatus must be increased, resulting in high costs. If the number of divisions is too small, it is difficult to set the angle θ of the housing 20-k to a desired inclination, and the etching rate uniformity cannot be maintained.

  Other configurations and the room temperature bonding method (operation of the room temperature bonding apparatus) are the same as those in the first embodiment.

Also in this embodiment, the same effect as that of the first embodiment can be obtained.
In addition to the effects of the first embodiment, the angle and distance of the high-speed atomic beam source can be adjusted, so that the etching distribution can be finely adjusted, and the uniform activation surface can be more easily adjusted. Can be adjusted to obtain This is because the etching rate on the surface of the wafer w and its distribution are correlated with the distance between the fast atom beam source (surface activation source) and the wafer and the incident angle of the irradiation axis.

(Third embodiment)
A fast atom beam source, a room temperature bonding apparatus, and a room temperature bonding method according to a third embodiment will be described. In the second embodiment, a plurality of upper atom beam sources and a plurality of lower atom beam sources each having a shape obtained by dividing the ring into a plurality of parts are used. In this embodiment, a high-speed atom beam source is provided on the upper and lower sides. A common fast atom beam source is used for the upper side and the lower side. Hereinafter, differences from the second embodiment will be mainly described.

  FIG. 12 is a perspective view schematically showing the fast atom beam source 19 according to the present embodiment.

  In the present embodiment, in the second embodiment, for example, the upper atomic beam source 18 is removed, and the lower atomic beam source 17 performs the function of combining the upper atomic beam source 18 and the lower atomic beam source 17. A single fast atomic beam source 19 is used. That is, the upper atomic beam sources 18-1 to 18-4 are removed, and the distance between the upper and lower wafers is adjusted so that the distance Bb between the beam source and the upper wafer coincides with the distance Ba between the lower wafer and each incident angle. Can be set as fast atom beam sources 19-1 to 19-4.

  In this case, when irradiating the lower wafer w with the fast atom beam, the fast atom beam source 19-k is tilted by the position adjusting mechanism 31 so as to face the lower side, and becomes the state of the fast atom beam source 19-ka. . As a result, the irradiation axis Ba of the fast atom beam source 19-ka can intersect the lower wafer w at a desired angle α. Similarly, when irradiating the upper wafer w with the fast atom beam, the fast atom beam source 19-k is tilted by the position adjusting mechanism 31 so as to face the upper side, and becomes the state of the fast atom beam source 19-kb. As a result, the irradiation axis Bb of the fast atom beam source 19-kb can intersect the upper wafer w at a desired angle α.

  Other configurations and the room temperature bonding method (operation of the room temperature bonding apparatus) are the same as those in the second embodiment.

Also in this embodiment, the same effect as in the second embodiment can be obtained.
In addition, by sharing the split ring-shaped fast atom beam source as the activation source for the upper and lower wafers, compared to the configuration of the second embodiment having a set of fast atom beam sources for each wafer. The cost can be reduced and the room temperature bonding apparatus can be downsized.

(Fourth embodiment)
A fast atom beam source, a room temperature bonding apparatus, and a room temperature bonding method according to a fourth embodiment will be described. In the second and third embodiments, a fast atom beam source having a shape in which a ring is divided into a plurality of parts is used. However, in this embodiment, the shape of the fast atom beam source is changed so as to facilitate manufacture. ing. Hereinafter, differences from the second and third embodiments will be mainly described.

  FIG. 13A is a plan view schematically showing the configuration of the fast atom beam source according to the second and third embodiments. As described in the second and third embodiments, the arcuate inner surface 20p in which the irradiation hole portion 22 of the partial housing 20-k is formed is located with respect to the center of the wafer w. It is a curved surface along the outer periphery of the concentric circle L.

  FIG. 13B is a plan view schematically showing the configuration of the fast atom beam source according to the present embodiment. The inner surface 20ps of the arc shape in which the irradiation hole portion 22 of the partial housing 20-k of the present embodiment is formed circumscribes the circumference of a circle L that is concentric with the center of the wafer w. It is a plurality of planes. The plurality of planes are arranged along the circumference and are connected to each other on both sides. The plurality of planes can be regarded as a shape of a part of a polyhedron circumscribing the circumference of the circle L. Each plane includes one irradiation hole 22. At that time, the normal line of each plane is parallel to the irradiation axis B of the irradiation hole 22. Also in this case, it is desirable that the irradiation holes (23) in the irradiation hole portion 22 are arranged at equal intervals or continuously. Note that the arc-shaped outer surface 20q in which the irradiation hole 22 of the partial housing 20-k is not formed is a curved surface along the circumference of another circle that is concentric with the center of the wafer w. There may be a plurality of planes circumscribing the circumference.

  FIG. 13C is a plan view schematically showing another configuration of the fast atom beam source according to the present embodiment. The partial housing 20-k in this case includes a plurality of partial housings obtained by further dividing the partial housing 20-k of FIG. 13B. In the example of this figure, the partial housing 20-k includes partial housings 20-k1, 20-k2, 20-k3, 20-k4, and 20-k5. The partial housing 20-kj (j = 1 to 5) has a box shape and has one irradiation hole portion 22. The surface 20 ps having the irradiation hole 22 is a plane that circumscribes the circumference of a circle L that is concentric with the center of the wafer w. The plurality of partial housings 20-k1 to 20-k5 are arranged so that the surfaces 20p are arranged along the circumference and in contact with both sides.

  Other configurations and room temperature bonding methods (operation of the room temperature bonding apparatus) are the same as those in the second and third embodiments.

Also in this embodiment, the same effects as those in the second and third embodiments can be obtained.
Further, when the irradiation hole portion 22 including the irradiation hole 23 of the fast atom beam or the ion beam is manufactured from a material that is difficult to be curved, such as a carbon material, the irradiation hole portion 22 can be easily formed by making the surface 20p flat. Can be manufactured. Thereby, the manufacturing cost of the high-speed atomic beam source can be reduced.

  As described above, in the high-speed atomic beam source of each of the above embodiments and the room temperature bonding apparatus using the same, it is possible to bring the large-diameter wafer surface into a uniform active state. Thereby, the surface roughness of the bonded wafer (substrate) can be made uniform and the cleanliness can be made uniform. As a result, variation in bonding strength over the entire surface of the wafer (substrate) is suppressed, and bonding quality is improved.

  In the fast atom beam source and the room temperature bonding apparatus using the same according to each of the above embodiments, the fast atom beam can be concentrated on the wafer (substrate) to be activated. Therefore, etching of parts other than the wafer (substrate) is reduced. Therefore, impurity deposition on the bonded wafer (substrate) is prevented. As a result, particle scattering to the bonded wafer (substrate) can be prevented, and the bonding quality is improved.

  In the fast atomic beam source of each of the above embodiments and the room temperature bonding apparatus using the same, the yield of devices formed on the wafer (substrate) is improved by the above-described effects.

  The room temperature bonding apparatus according to the present invention can omit the plurality of gas type switching mechanisms. Also in this case, the room-temperature bonding apparatus can activate the lower wafer and the upper wafer more uniformly in the same manner as in the above-described embodiment, and the lower wafer and the upper wafer can be more appropriately activated. Can be bonded at room temperature.

  The present invention is not limited to the embodiments described above, and it is obvious that the embodiments can be appropriately modified or changed within the scope of the technical idea of the present invention. In addition, the technology described in each embodiment can be used in other embodiments as long as no contradiction occurs.

DESCRIPTION OF SYMBOLS 1: Room temperature bonding apparatus 2: Load lock chamber 3: Bonding chamber 5: Gate 6: Gate valve 7: Shelf 8: Transfer robot 9: Lid 10: Vacuum exhaust apparatus 11: Positioning stage carriage 12: Positioning mechanism 14: Electrostatic Chuck 15: Pressure welding mechanism 16: Activator 17, 17-k, 17-1 to 17-4: Lower atom beam source 18, 18-k, 18-1 to 18-4: Upper atom beam source 19, 19 -K, 19-ka, 19-kb, 19-1 to 19-4: Fast atom beam source 20: Housing 20-k, 20-kj, 20-k1 to 20-k5: Partial housing 20a: Cathode 20b : Cover 20c: Gas inlet 20p, 20ps: Surface 20q, 20qs: Surface 21, 21-k: Electrode body 22: Irradiation hole 23: Irradiation hole 24: Center points 31, 31a, 31b: Position adjustment mechanism 61: Gas type switching mechanism 62-i, 62-1 to 62-4: Gas supply device 63-i, 63-1 to 63-4: Valve 64: Pipe line 71: Room temperature bonding apparatus controller 72: Conveying part 73: Activation part 74: Joining part

Claims (15)

Provided around the central axis, has a cylindrical ring shape having an inner space, a housing comprising said central axis side more radiation holes aligned equidistant or continuously on an inner side surface of said ring ,
An electrode body provided in the internal space so as to extend along the extending direction of the internal space of the housing;
It said housing and said electrode body is configured in the internal space of each of the housing as a saddle field type cathode and anode to generate an electric field of,
The beam emitted from the internal space of the housing, towards Iteiru fast atom beam source to the center axis of the ring through each of the plurality of radiation holes. The fast atom beam source of claim 1,
Wherein the plurality of irradiation axis as a normal line of the center of the inner surface of the ring corresponding to the plurality of irradiation holes, fast atom beam source intersect at one point on the central axis of the ring. The fast atom beam source according to claim 1 or 2,
The housing includes a plurality of partial housings having an arc shape obtained by dividing the ring,
The high-speed atomic beam source is provided with a plurality of electrode bodies provided inside the plurality of partial housings and extending along the arc. The fast atom beam source according to any one of claims 1 to 3,
The said electrode body is a fast atom beam source containing two electrode rods extended along the extending direction of the said internal space of the said ring, and paralleled up and down. The fast atom beam source according to claim 3,
Each of the plurality of partial housings is
The inner surface of the ring, the central axis fast atom beam source which is formed by a plurality of planes aligned so as to circumscribe a circle around the said ring. The fast atom beam source according to claim 3,
Each of the plurality of partial housings includes a plurality of box-shaped housings,
Wherein the plurality of box-shaped housing, fast atom beam source are arranged side by side so as to circumscribe a circle about the central axis of the ring. The fast atom beam source according to any one of claims 1 to 6,
Each of the plurality of irradiation holes has a horizontally long shape along the circumference of the ring. A first fast atom beam source that respectively emits a plurality of first activation beams irradiated on a first surface of a first substrate;
A second fast atom beam source that respectively emits a plurality of second activation beams irradiated to the second surface of the second substrate;
A pressure contact mechanism that joins the first substrate and the second substrate by bringing the first surface and the second surface irradiated with the first activation beam and the second activation beam into contact with each other. And
The first fast atom beam source includes the fast atom beam source according to any one of claims 1 to 7,
The plurality of first activation beams are irradiated from the plurality of irradiation holes,
The central axis of the ring overlaps a center of the first substrate,
The second fast atom beam source includes the fast atom beam source according to any one of claims 1 to 7,
The plurality of second activation beams are irradiated from the plurality of irradiation holes,
The central axis of the ring, the room-temperature bonding apparatus that overlaps with the center of the second substrate. The room temperature bonding apparatus according to claim 8,
A plurality of position adjusting mechanisms corresponding to the first fast atom beam source and the second fast atom beam source;
Said position adjusting mechanism corresponding to the first fast atom beam source, the first fast atom beam source, a plurality of normal is the first front surface of said plurality of irradiation holes of the plurality of position adjusting mechanism To the first substrate so as to intersect at a predetermined first angle,
Said position adjusting mechanism corresponding to the second fast atom beam source, the second fast atom beam source, said plurality of normals the second table of the plurality of irradiation holes of the plurality of position adjusting mechanism A room temperature bonding apparatus that faces the second substrate so as to intersect the surface at a predetermined second angle. The room temperature bonding apparatus according to claim 9,
Wherein the first fast atom beam source wherein a plurality of said plurality of normal and said first front surface of the illumination hole of the intersect near the center of the first substrate,
Wherein the second fast atom beam source wherein a plurality of said plurality of normal and the second front surface of the illumination hole of the room-temperature bonding apparatus intersecting near the center of the second substrate. A first fast atom beam source that respectively emits a plurality of first activation beams irradiated on a first surface of a first substrate;
A second fast atom beam source that respectively emits a plurality of second activation beams irradiated to the second surface of the second substrate;
A pressure contact mechanism that joins the first substrate and the second substrate by bringing the first surface and the second surface irradiated with the first activation beam and the second activation beam into contact with each other. When
Comprising
The first fast atom beam source includes the fast atom beam source according to claim 3,
The plurality of first activation beams are irradiated from the plurality of irradiation holes,
The central axis of the ring overlaps the center of the first substrate;
The second fast atom beam source includes the fast atom beam source according to claim 3,
The plurality of second activation beams are irradiated from the plurality of irradiation holes,
The first fast atom beam source and the second fast atom beam source that are overlapped with the center of the second substrate are integrated with the center axis of the ring ,
The single fast atom beam source as the integral fast atom beam source is
A plurality of position adjustment mechanisms corresponding to the single fast atom beam source as the integral fast atom beam source;
The plurality of position adjustment mechanisms include:
Wherein a single fast atom beam source, so that the plurality of normal line of the plurality of illumination holes intersect at the first front surface and a predetermined first angle, toward the first substrate,
Said single fast atom beam source, so that the plurality of normal line of the plurality of illumination holes intersect at the second front surface and a predetermined second angle, the room-temperature bonding apparatus for directing to said second substrate. The room temperature bonding apparatus according to any one of claims 8 to 11,
The first fast atom beam source and the second fast atom beam source, the plurality of irradiation holes is line symmetry with respect to the center axis of the first fast atom beam source or the second fast atom beam source Arranged at room temperature bonding equipment. The room temperature bonding apparatus according to claim 12,
In each of the first fast atom beam source and the second fast atom beam source, the plurality of irradiation hole portions are approximately equally divided into 20 or more on the inner periphery of the ring, or irradiation holes are continuously formed. Room-temperature bonding apparatus having a shaped shape. A fast atom beam source comprising a single partial housing having an arc shape as one of the plurality of partial housings in the fast atom beam source according to claim 3. A room temperature bonding method using the room temperature bonding apparatus according to any one of claims 8 to 13,
In the first fast atom beam source, irradiating the plurality of first activation beam, respectively a first front surface of the first substrate,
In the second fast atom beam source irradiating a plurality of second activation beam, respectively a second front surface of the second substrate,
In pressing mechanism, by contacting the plurality of the first front surface of the first activation beam and the plurality of second activation beam is irradiated respectively with said second front surface, and said first substrate A room temperature bonding method comprising: bonding the second substrate.

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