Coating unit and substrate bonding apparatus having the same

Abstract

A coating unit includes: a chuck that holds a bonded substrate representing two substrates after bonding, and rotates around an axis orthogonal to a main surface of the bonded substrate and passing through the center of the main surface; and a filling liquid nozzle that supplies a filling liquid to an annular groove formed between the outer peripheral portions of the two substrates after bonding by ejecting a plurality of liquid droplets of the filling liquid toward the bonded substrate held by the chuck, wherein the filling liquid changes into a filling body in a solid or semi-solid state.

Description

Technical Field

[0001] This invention relates to a coating unit for applying a filler liquid to two bonded substrates and a substrate bonding apparatus having the coating unit. Substrates include, for example, substrates for FPD (Flat Panel Display) devices such as semiconductor wafers, liquid crystal display devices or organic EL (electroluminescence) display devices, substrates for optical discs, substrates for magnetic disks, substrates for optical discs, substrates for photomasks, ceramic substrates, substrates for solar cells, etc. Background Technology

[0002] Patent Document 1 discloses an end-state confirmation device capable of determining whether a protective component formed on the outer peripheral end of a substrate has internal defects. Paragraph 0087 of Patent Document 1 states: "If..." Figure 10 As shown in Figure 11, the end state confirmation device 1 of the second embodiment, in addition to the structure of the end state confirmation device 1 of the first embodiment, also includes a protection member forming section LN for forming a protection member w4 at the outer peripheral end of the bonding substrate W. The protection member forming section LN is connected to a supply system (not shown) for supplying a coating liquid for the protection member, and has a nozzle member capable of spraying the coating liquid supplied from the supply system.

[0003] Existing technical documents

[0004] Patent documents

[0005] Patent Document 1: Japanese Patent Application Publication No. 2023-43003 Summary of the Invention

[0006] The problem that the invention aims to solve

[0007] Patent document 1 only describes a "nozzle component capable of spraying out coating liquid supplied from the supply system", but it is not clear in what form the coating liquid is sprayed out from the nozzle component.

[0008] At least one embodiment of the present invention provides a coating unit and a substrate bonding apparatus having the coating unit, which can precisely control the amount of filler liquid supplied to the two bonded substrates.

[0009] Methods for solving problems

[0010] One embodiment of the present invention provides a coating unit comprising: a chuck that holds two bonded substrates (i.e., bonding substrates) while rotating about an axis orthogonal to the main surface of the bonding substrate and passing through the center of the main surface; and a filler nozzle that supplies the filler liquid to an annular groove formed between the outer peripheries of the two bonded substrates by spraying multiple droplets of filler liquid onto the bonding substrate held by the chuck, wherein the filler liquid is a solid or semi-solid filler. The bonding substrates comprise two parallel planes. The two planes of the bonding substrates are the non-bonding surfaces of the two bonded substrates. The main surface of the bonding substrate can be one of the two planes of the bonding substrates.

[0011] In the embodiment described, at least one of the following features may be added to the coating unit.

[0012] The filling fluid nozzle is an inkjet nozzle that causes multiple droplets of the filling fluid to fly towards the annular groove in approximately the same direction.

[0013] The coating unit further includes: a position detector that detects the position of the outer periphery of the bonding substrate held by the chuck; and a nozzle actuator that moves the filling liquid nozzle according to the position of the outer periphery detected by the position detector.

[0014] The coating unit further includes a control device that performs at least one of position control and flow control, wherein the position control is performed by causing the nozzle actuator to move the filler nozzle based on the position of the outer peripheral portion detected by the position detector while the position detector detects the position of the outer peripheral portion; and the flow control is performed by changing the amount of filler liquid ejected from the filler nozzle per unit time based on the position of the outer peripheral portion detected by the position detector while the position detector detects the position of the outer peripheral portion.

[0015] The coating unit further includes a void detector, which detects voids in the filling liquid or filler within the annular groove and voids between the bonding surfaces of the two substrates after bonding, while the chuck holds the bonding substrates.

[0016] The filling fluid nozzle comprises: a large-diameter nozzle that sprays multiple droplets of the filling fluid from a spray port onto the bonding substrate held by the chuck; and a small-diameter nozzle that sprays multiple droplets of the filling fluid from a spray port with an area smaller than the spray port of the large-diameter nozzle onto the bonding substrate held by the chuck.

[0017] Another embodiment of the present invention provides a substrate bonding apparatus comprising: a bonding unit for bonding two substrates; and a coating unit for coating the two substrates bonded by the bonding unit, i.e., the bonded substrates, with a filler liquid, wherein the filler liquid is a solid or semi-solid filler, the coating unit comprising: a chuck for holding the bonded substrates and rotating about an axis orthogonal to the main surface of the bonded substrates and passing through the center of the main surface; and a filler liquid nozzle for supplying the filler liquid to an annular groove formed between the outer peripheries of the two bonded substrates by spraying a plurality of droplets of the filler liquid onto the bonded substrates held by the chuck.

[0018] In the embodiment described, at least one of the following features may be incorporated into the substrate bonding device.

[0019] The bonding unit includes: a first chuck and a second chuck, which respectively hold the two substrates before bonding; and a bonding actuator, which causes the two substrates held by the first chuck and the second chuck to contact each other by moving the first chuck and the second chuck relative to each other. The coating unit further includes: a chamber that houses the chuck, the filling liquid nozzle, the first chuck, and the second chuck.

[0020] The bonding unit further includes a void detector, which detects the void between the bonding surfaces of the two substrates after bonding, as well as the void in the filling liquid or filling body within the annular groove. Attached Figure Description

[0021] Figure 1A This is a schematic diagram showing an example of the appearance of the two substrates before and after bonding.

[0022] Figure 1B This is a schematic diagram showing an example of the cross-sections of the two substrates before and after bonding.

[0023] Figure 1C This is a schematic diagram showing an example of the cross-sections of the two substrates before and after the filling liquid is supplied to the outer periphery of the two substrates after bonding.

[0024] Figure 1D This is a schematic diagram showing an example of the cross-sections of the two substrates before and after thinning following bonding.

[0025] Figure 2 This is a process diagram used to illustrate a substrate bonding method according to an embodiment of the present invention.

[0026] Figure 3 This is a schematic top view of a substrate bonding apparatus according to an embodiment of the present invention.

[0027] Figure 4AThis is a schematic diagram of the interior of the pre-activated alignment device viewed horizontally.

[0028] Figure 4B This is a schematic diagram of the interior of the pre-activated alignment unit viewed from directly above.

[0029] Figure 5A It is a schematic diagram of the interior of the activation unit viewed horizontally.

[0030] Figure 5B This is a schematic diagram of the interior of the activation unit as viewed from directly above.

[0031] Figure 6A This is a horizontal view of the interior of the pre-contraction cleaning unit.

[0032] Figure 6B This is a schematic diagram of the interior of the pre-construction cleaning unit viewed from directly above.

[0033] Figure 7A It is a horizontal view of the interior of the coating unit.

[0034] Figure 7B This is a schematic diagram of the interior of the coating unit viewed from directly above.

[0035] Figures 7C-7D This is a schematic diagram of the filling fluid nozzle.

[0036] Figure 8A It is a schematic diagram showing the interior of the joint unit from a horizontal perspective.

[0037] Figure 8B It is a schematic diagram showing the interior of the joint unit from a horizontal perspective.

[0038] Figure 9A It is a schematic diagram of the interior of the grinding unit viewed horizontally.

[0039] Figure 9B This is a schematic diagram of the interior of the grinding unit viewed from directly above.

[0040] Figure 10 This is a block diagram showing the electrical structure of the substrate bonding device.

[0041] Figure 11A This is a schematic cross-sectional view of the outer periphery of the substrate.

[0042] Figure 11B This is a schematic diagram of the interior of the coating unit viewed from directly above.

[0043] Figure 11C This is a schematic cross-sectional view showing the state of supplying filling liquid to the annular groove formed between the outer peripheries of the two bonded substrates.

[0044] Figure 11DThis is a schematic cross-sectional view showing the state of the gap between two substrates after bonding, detected using a void detector.

[0045] Figure 12A This is a schematic diagram of the interior of a coating unit in another embodiment of the present invention, viewed horizontally.

[0046] Figure 12B It is a schematic diagram showing the state of the substrate, filling liquid, and voids within the filling after the bonding is completed.

[0047] Figure 13 It is a schematic top view of the substrate showing the device area and the non-device area. Detailed Implementation

[0048] Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings.

[0049] In the following description, "bonded substrate W" refers to the two substrates W after bonding, "pre-bonding substrate W" refers to the single substrate W before bonding, and "post-bonding substrate W" refers to the single substrate W after bonding. "Lamination" and "bonding" have the same meaning.

[0050] The first substrate W1 refers to the substrate W before bonding. The second substrate W2 refers to other substrates W before bonding. The first substrate W1 and the second substrate W2 after bonding refer to the bonded substrate W. The two substrates W after bonding also refer to the bonded substrate W. In the case where it can be any of the bonded substrate W, the substrate W before bonding, and the substrate W after bonding, it is simply referred to as substrate W.

[0051] Figure 1A This is a schematic diagram showing an example of the appearance of the two substrates W before and after bonding. Figure 1B This is a schematic diagram showing an example of the cross-section of the two substrates W before and after bonding. Figure 1C This is a schematic diagram showing an example of the cross-section of the two substrates W before and after the filling liquid FL is supplied to the outer periphery of the two bonded substrates W. Figure 1D This is a schematic diagram showing an example of the cross-sections of the two substrates W before and after thinning following bonding.

[0052] like Figure 1A As shown, the first substrate W1 and the second substrate W2 are smooth circular plates with equal diameters. The diameters of the first substrate W1 and the second substrate W2 can be 300 mm or other diameters. The thermal expansion coefficients of the first substrate W1 and the second substrate W2 can be equal or different. The first substrate W1 includes a circular substrate WD1, and the second substrate W2 includes a circular substrate WD2. Substrates WD1 and WD2 are made of semiconductors such as single-crystal silicon. Substrates WD1 and WD2 can also be made of materials other than semiconductors.

[0053] Both substrates WD1 and WD2 include parallel circular front and back surfaces, and annular end faces connecting the outer edges of the front and back surfaces. The front and back surfaces of substrate WD1 are parallel flat surfaces. The same applies to the front and back surfaces of substrate WD2. The front surfaces of substrates WD1 and WD2 are device forming surfaces for forming devices such as transistors. The back surfaces of substrates WD1 and WD2 are non-device forming surfaces where no devices are formed. Both the front and back surfaces of substrate WD1 or WD2 can be device forming surfaces.

[0054] When viewed in a direction perpendicular to the surface of substrate WD1, a V-shaped notch is formed on the outer periphery of substrate WD1, opening at the end face of substrate WD1. Alternatively, the outer periphery of substrate WD1 may not be a notch, but rather a positioning flat edge (a so-called flat edge). The notch and positioning flat edge indicate the crystal orientation of substrate WD1 or substrate WD2. The first substrate W1 is positioned circumferentially with reference to the notch or positioning flat edge of the first substrate W1. The same applies to the second substrate W2.

[0055] like Figure 1B As shown, the first substrate W1 includes a device layer WC1 covering the surface of a substrate WD1 and a bonding layer WB1 covering the surface of the device layer WC1. The second substrate W2 includes a device layer WC2 covering the surface of a substrate WD2 and a bonding layer WB2 covering the surface of the device layer WC2. Devices such as transistors are disposed on the device layers WC1 and WC2. The devices are covered by the bonding layers WB1 and WB2. The bonding layers WB1 and WB2 are transparent or translucent insulating layers. The bonding layers WB1 and WB2 can be silicon oxide films or thin films of materials other than silicon oxide. In the former case, the bonding layers WB1 and WB2 can be silicon oxide films made using TEOS (tetraethoxysilane).

[0056] The surface of the bonding layer WB1 of the first substrate W1 is the bonding surface WA1 of the first substrate W1. The surface of the bonding layer WB2 of the second substrate W2 is the bonding surface WA2 of the second substrate W2. The first substrate W1 and the second substrate W2 are bonded such that the bonding surface WA1 of the first substrate W1 and the bonding surface WA2 of the second substrate W2 are opposite to each other. The surface of the first substrate W1 is the bonding surface WA1, which is in contact with the atmosphere in the space in which the first substrate W1 is disposed. The surface of the second substrate W2 is the bonding surface WA2, which is in contact with the atmosphere in the space in which the second substrate W2 is disposed.

[0057] Figure 2 This is a process diagram illustrating a substrate bonding method according to an embodiment of the present invention. During the bonding of the first substrate W1 and the second substrate W2, an activation step is performed to activate the bonding surface WA1 of the first substrate W1 and the bonding surface WA2 of the second substrate W2. Figure 2 Step S1) involves cleaning and drying the two activated substrates W. Figure 2 Step S2). Then, a reversal process is performed to flip one of the first substrate W1 and the second substrate W2. Figure 2 Step S3).

[0058] After one of the first substrate W1 and the second substrate W2 is reversed, a confirmation alignment process is performed. Figure 2 Step S4), Adjusting the alignment process ( Figure 2 Step S5) and substrate contact process ( Figure 2 In step S6), regarding the alignment confirmation process, the alignment of the relative positions and angles of the first substrate W1 and the second substrate W2 is confirmed. Regarding the alignment adjustment process, the alignment of the first substrate W1 and the second substrate W2 is adjusted according to the confirmed alignment. Regarding the substrate contact process, the first substrate W1 and the second substrate W2 are joined by bringing the aligned first substrate W1 and the second substrate W2 into contact. Afterwards, an inspection process is performed. Figure 2 In step S7), regarding the inspection process, the bonding accuracy of the first substrate W1 and the second substrate W2 is inspected, that is, the offset of the position of the two substrates W after bonding and the offset of the angle (angle around the center of the substrate W) of the two substrates W after bonding.

[0059] The activation process can be a plasma treatment in which the bonding surface WA1 of the first substrate W1 and the bonding surface WA2 of the second substrate W2 are irradiated with plasma such as oxygen plasma. In this case, moisture in the air and moisture supplied to the substrate W during the cleaning process come into contact with the bonding surfaces WA1 of the first substrate W1 and WA2 of the second substrate W2, which have been irradiated with plasma, forming hydrophilic groups such as hydroxyl (OH) groups on the bonding surfaces WA1 of the first substrate W1 and WA2 of the second substrate W2. Plasma treatment is an example of surface modification that modifies the surface of the substrate W. The activation process can be a wet treatment in which a hydrophilic liquid that forms hydrophilic groups is supplied to the bonding surfaces WA1 of the first substrate W1 and WA2 of the second substrate W2.

[0060] The substrate contact process can be a process of directly bonding two substrates W in an atmosphere at room temperature (e.g., 20°C to 30°C). Alternatively, the substrate contact process can be a face-to-face bonding process where the surfaces of the two substrates W are facing each other. In this case, the surfaces of the two substrates W correspond to the bonding surface WA1 of the first substrate W1 and the bonding surface WA2 of the second substrate W2. The substrate contact process can also be a process where one substrate W is not pressed against the other, or one substrate W is pressed against the other with pressure that does not damage the devices formed on the two substrates W, thereby bonding the two substrates W.

[0061] Figure 1B This represents the cross-section obtained by cutting the first substrate W1 and the second substrate W2 with a plane orthogonal to the first substrate W1 and the second substrate W2. Figure 1B The ratio of the thickness of device layer WC1 and device layer WC2 to the thickness of bonding layer WB1 and bonding layer WB2 shown may not be the same as the actual ratio. Figure 1B This example illustrates an instance where a hydroxyl group, as a hydrophilic group, is formed on the bonding surface WA1 of the first substrate W1 and the bonding surface WA2 of the second substrate W2 before bonding. In this example, the oxygen atom (O) in the hydroxyl group is bonded to the silicon atom (Si) in the bonding layers WB1 and WB2.

[0062] Multiple hydroxyl groups terminate the bonding surfaces WA1 and WA2 of the first substrate W1 and the second substrate W2 before bonding. When the bonding surfaces WA1 and WA2 of the first substrate W1 and the second substrate W2 are brought into contact, the first substrate W1 and the second substrate W2 are bonded by intermolecular forces acting between the two hydroxyl groups. Depending on the situation, water molecules may detach from the two hydroxyl groups, and silicon atoms in the bonding layer WB1 of the first substrate W1 and silicon atoms in the bonding layer WB2 of the second substrate W2 may bond via oxygen atoms. In this way, the first substrate W1 and the second substrate W2 are bonded.

[0063] like Figure 1C As shown, after the first substrate W1 and the second substrate W2 are bonded together, a coating process is performed. Figure 2 In step S8), regarding the coating process, a filling liquid FL is applied to the annular groove WG formed between the outer peripheries of the first substrate W1 and the second substrate W2 after bonding. Then, as... Figure 1D As shown, the grinding process is performed. Figure 2 Step S9) and cleaning process ( Figure 2 In step S10), regarding the grinding process, the first substrate W1 and the second substrate W2 after bonding are ground to make the first substrate W1 and the second substrate W2 after bonding, i.e., the bonding substrate W, thinned. Regarding the cleaning process, the thinned bonding substrate W is cleaned and dried. Figure 1D This illustrates an example of reducing the thickness of the bonding substrate W by grinding the first substrate W1. Alternatively, the thickness of the second substrate W2 can be reduced instead of the thickness of the first substrate W1.

[0064] Inspection process ( Figure 2 Step S7) can also be performed during the coating process ( Figure 2 The process can be performed after step S8, not before. In this case, it can be performed after the grinding process ( Figure 2 The inspection process can be performed before step S9), or after the grinding process. Alternatively, the inspection process can be performed both before and after the grinding process. In this case, the bonding accuracy before and after the grinding process can be compared. A pass / fail determination can be made based on whether the change in bonding accuracy exceeds a threshold. A pass / fail rate can be calculated based on the pass / fail determination, or a pass / fail mapping can be created representing the relationship between substrates W that have undergone pass / fail determination and qualified substrates W. At least one of the pass / fail rate and the pass / fail mapping can be recorded or displayed.

[0065] like Figure 1C and Figure 1D As shown, the filler solution FL is a liquid that transforms into a solid or semi-solid filler FS. The filler solution FL can be a solution of the filler FS (equivalent to the solute) dissolved in a solvent, or a liquid of the filler FS (with a concentration of 100% or approximately 100%), or any other liquid. When the filler solution FL is a solution containing the filler FS and a solvent, the solvent can be a liquid containing a substance with a higher volatility than water, such as IPA (isopropanol). For example, the filler solution FL can be an SOG (spin-on-glass) liquid containing a siloxane component (equivalent to the solute) and an alcohol (equivalent to the solvent).

[0066] At the start of the grinding process, the filler liquid FL in the annular tank WG changes into filler FS. Depending on the needs, treatments that induce or promote the change from filler liquid FL to filler FS can be performed before the grinding process. For example, if the change from filler liquid FL to filler FS is caused by evaporation of the filler liquid FL, a portion of the filler liquid FL can be evaporated by heating the filler liquid FL and reducing the air pressure, respectively. If the change from filler liquid FL to filler FS is caused by solidification of the filler liquid FL, the filler liquid FL can be solidified by heating the filler liquid FL and irradiating the filler liquid FL with light, respectively. These treatments can be performed during the supply of filler liquid FL, after the supply of filler liquid FL is stopped, or both.

[0067] Next, the substrate bonding apparatus 1 that bonds two substrates W as described above will be described.

[0068] Figure 3This is a schematic top view of a substrate bonding apparatus 1 according to an embodiment of the present invention. Unless otherwise specified, the terms "up / down," "left / right," and "front / back" in the following description refer to the up / down, left / right, and front / back directions of the substrate bonding apparatus 1. The up / down direction is the vertical direction. The left / right and front / back directions are two horizontal directions that are orthogonal to each other. The arrangement direction of the plurality of carriers CA held in the plurality of loading ports LP is the left / right direction. Each carrier CA is held in the loading port LP with its opening facing rearward.

[0069] The substrate bonding apparatus 1 is a device for bonding two circular substrates W. The substrate bonding apparatus 1 includes: multiple loading ports LP, on which multiple carriers CA, such as FOUPs (Front-Opening Unified Pods), containing multiple substrates W are placed one by one; multiple processing units 2, which process the substrates W transported from the multiple loading ports LP; a transport system TS, which transports the substrates W between the multiple loading ports LP and the multiple processing units 2; and an outer wall 1a, which forms a sealed space housing the multiple processing units 2 and the transport system TS. The substrate bonding apparatus 1 also includes: a control device 3, which controls the substrate bonding apparatus 1.

[0070] Figure 3 This example illustrates a configuration with three loading ports LP. The three loading ports LP include: a first loading port LP1, which houses the carrier CA containing the first substrate W1; a second loading port LP2, which houses the carrier CA containing the second substrate W2; and a third loading port LP3, which houses the carrier CA containing the joined first substrate W1 and second substrate W2. The first and second loading ports LP1 and LP2 are loading inlets for the carrier CA containing the substrates W to be joined by the substrate joining device 1. The third loading port LP3 is the unloading outlet for the carrier CA containing the two substrates W joined by the substrate joining device 1.

[0071] Multiple processing units 2 include: a pre-activation alignment unit 10, an activation unit 20, a pre-bonding cleaning unit 30, a pre-bonding alignment unit 40, a bonding unit 50, a grinding unit 60, and a post-grinding cleaning unit 70. Figure 3 This example shows two of each of the pre-activation alignment unit 10, activation unit 20, pre-bonding cleaning unit 30, pre-bonding alignment unit 40, and coating unit 40, with the pre-bonding alignment unit 40 being integrated with the coating unit 40.

[0072] The pre-activation alignment unit 10 is a unit that positions the substrate W circumferentially based on a notch or positioning flat edge. The pre-bonding alignment unit is the same. The activation unit 20 is a unit that performs plasma treatment to activate the surface or back of the substrate W by bringing plasma into contact with the surface or back of the substrate W. The pre-bonding cleaning unit 30 is a unit that cleans the substrate W by supplying cleaning fluid to the substrate W.

[0073] The bonding unit 50 is a unit that bonds two substrates W by bringing them into contact. The coating unit 40 applies coating to an annular groove WG (see reference) formed between the outer peripheries of the two bonded substrates W. Figure 1C The unit supplies filling liquid. The polishing unit 60 is a unit that thins the two bonded substrates W by polishing them. The post-polishing cleaning unit 70 is a unit that cleans the two substrates W by supplying cleaning liquid to the two substrates W that have been thinned by polishing.

[0074] The conveying system TS conveys substrate W from the first loading port LP1 and the second loading port LP2 to multiple processing units 2, and from the multiple processing units 2 to the third loading port LP3. The conveying system TS also conveys substrate W between the multiple processing units 2. The conveying system TS may include: at least one conveying robot TR, which... Figure 3 One or more substrates W are transported horizontally on the transport path TP, which is shown by the thick line.

[0075] The transport robot TR includes at least one robotic arm TH that holds a substrate W in a horizontal orientation. The transport robot TR moves along the transport path TP while using the robotic arm TH to keep the substrate W horizontal. Figure 3 This represents an example where the transport path TP extends from each of the first loading port LP1 and the second loading port LP2 to multiple processing units 2, and returns from the multiple processing units 2 to the third loading port LP3.

[0076] The following describes the various processing units 2. First, the pre-activation alignment unit 10 will be described.

[0077] Figure 4A This is a schematic diagram of the interior of the pre-activated alignment device 10 viewed horizontally. Figure 4B This is a schematic diagram of the interior of the pre-activated alignment device 10 as viewed from directly above.

[0078] like Figure 4A and Figure 4B As shown, the pre-aligner 10 includes: a chamber 11 that forms an internal space for the substrate W and an opening for the substrate W to enter and exit the internal space; and a chuck 14 that holds the substrate W horizontally within the chamber 11. The chamber 11 includes: a partition 12 that forms the internal space and the opening; and a door 13 that opens and closes the opening by moving relative to the partition 12.

[0079] The pre-aligner 10 further includes: an electric motor 15, which rotates the chuck 14 to rotate the substrate W about a vertical rotation center A1 passing through the center of the substrate W held in the chuck 14; an outer peripheral position sensor 16, which determines the orientation of the notch or positioning flat edge by detecting the contour shape of the substrate W; and a control device 3, which rotates the chuck 14 by the electric motor 15 according to the detection value of the outer peripheral position sensor 16, so that the substrate W is stationary at a position where the orientation of the notch or positioning flat edge is consistent with the reference direction.

[0080] The chuck 14 can be a mechanical chuck that holds the substrate W horizontally by pressing a plurality of chuck pins horizontally against the end face of the substrate W, or a vacuum chuck that holds the substrate W horizontally by adsorbing the lower surface of the substrate W onto the upper surface of a rotating base disposed below the substrate W. Figure 4A and Figure 4B This illustrates an example of the latter. In the latter case, the peripheral position sensor 16 can determine the center position of the substrate W by detecting the contour shape of the substrate W. In this case, the activated front alignment device 10 may further include a centering actuator that moves the center of the substrate W close to the rotation center A1 of the substrate W by horizontally moving the chuck 14.

[0081] An actuator is a device that converts driving energy, representing electrical, fluid, magnetic, thermal, or chemical energy, into mechanical work, i.e., the motion of a tangible object. Actuators include electric motors (rotary motors), linear motors, cylinders, and other devices. When the motion of the actuator differs from the motion of the object, a motion converter can be provided to convert the actuator's motion into linear or rotary motion. For example, when the actuator is an electric motor that causes the object to move linearly, a motion converter such as a ball screw or ball nut can convert the rotation of the electric motor into linear motion.

[0082] Next, the activation unit 20 will be described.

[0083] Figure 5A This is a schematic diagram of the interior of the activation unit 20 viewed horizontally. Figure 5B This is a schematic diagram of the interior of the activation unit 20 as viewed from directly above.

[0084] like Figure 5A and Figure 5BAs shown, the activation unit 20 includes: a chamber 21 forming an internal space for the substrate W and an opening for the substrate W to enter and exit the internal space; a lower electrode 24L supporting the substrate W horizontally within the chamber 21; an upper electrode 24u positioned above the substrate W held by the lower electrode 24L; a gas pipe 25p supplying processing gas between the upper electrode 24u and the lower electrode 24L; a gas valve 25v opening and closing the gas pipe 25p; a power supply 26 converting the processing gas between the upper electrode 24u and the lower electrode 24L into plasma; and a vacuum pump 27 discharging gas from the internal space. The chamber 21 includes: a partition wall 22 forming the internal space and the opening; and a door 23 opening and closing the opening by moving relative to the partition wall 22.

[0085] Although not shown, the gas valve 25V includes: a valve body with an annular valve seat for gas passage; a valve core movable relative to the valve seat; and an actuator that moves the valve core between a closed position where the valve core contacts the valve seat and an open position where the valve core leaves the valve seat. The actuator may be a pneumatic actuator, an electric actuator, or something else. Control device 3 (see reference) Figure 3 The gas valve 25V is opened and closed by controlling the actuator.

[0086] Next, the pre-joining cleaning unit 30 will be described.

[0087] Figure 6A This is a schematic diagram of the interior of the pre-contact cleaning unit 30 viewed horizontally. Figure 6B This is a schematic diagram of the interior of the pre-joining cleaning unit 30 viewed from directly above.

[0088] like Figure 6A and Figure 6B As shown, the pre-joining cleaning unit 30 includes: a chamber 31 forming an internal space for the substrate W and an opening for the substrate W to enter and exit the internal space; a chuck 34 holding the substrate W horizontally within the chamber 31; an electric motor 35 that rotates the chuck 34 to rotate the substrate W about a vertical rotation center A1 passing through the central portion of the substrate W held by the chuck 34; and one or more processing liquid nozzles 36 that spray cleaning liquid or other processing liquids toward the substrate W held by the chuck 34. The chamber 31 includes: a partition 32 forming the internal space and the opening; and a door 33 that opens and closes the opening by moving relative to the partition 32. The cleaning liquid can be pure water (deionized water (DIW)) or a liquid other than pure water.

[0089] Although not illustrated, the post-grinding cleaning unit 70 (see reference) Figure 3The post-grinding cleaning unit 70 has the same structure as the pre-bonding cleaning unit 30. Therefore, the post-grinding cleaning unit 70 includes: a chamber 31, a chuck 34, an electric motor 35, and a processing fluid nozzle 36. The chamber 31 includes a partition wall 32 and a door 33. The difference between the pre-bonding cleaning unit 30 and the post-grinding cleaning unit 70 is that the pre-bonding cleaning unit 30 cleans the first substrate W1 or the second substrate W2, while the post-grinding cleaning unit 70 cleans the first substrate W1 or the second substrate W2 after bonding and grinding.

[0090] Next, the coating unit 40 will be described.

[0091] Figure 7A This is a schematic diagram of the interior of the coating unit 40 viewed horizontally. Figure 7B This is a schematic diagram of the interior of the coating unit 40 as viewed from directly above. Figure 7C and Figure 7D This is a schematic diagram of the filling fluid nozzle 49.

[0092] The coating unit 40 includes a pre-joint alignment device. The pre-joint alignment device has an interface with the activation pre-alignment device 10 (see reference 10). Figure 4A and Figure 4B The coating unit 40 has the same structure as the 10. Therefore, the coating unit 40 includes: a chamber 11, a partition 12, a door 13, a chuck 14, an electric motor 15, and a peripheral position sensor 16. Hereinafter, to distinguish between the structure of the pre-activation alignment device 10 and the structure of the coating unit 40, the chamber 11, partition 12, door 13, chuck 14, electric motor 15, and peripheral position sensor 16 used in the coating unit 40 will be referred to as chamber 41, partition 42, door 43, chuck 44, electric motor 45, and peripheral position sensor 46. The chuck 44 is the aforementioned vacuum chuck.

[0093] The coating unit 40 includes at least one filling nozzle 49 for spraying filling liquid toward the substrate W held by the chuck 44. Figure 7B This illustrates an example with two filling nozzles 49. Two filling nozzles 49 are spaced apart in the rotational direction Dr of the chuck 44. The two filling nozzles 49 spray filling fluid toward two target positions separated in the rotational direction Dr of the chuck 44. Each target position is an annular groove WG (see reference). Figure 1C The location within ).

[0094] The filler nozzle 49 is a droplet nozzle that produces multiple droplets of filler liquid that are dispersed toward the object to be coated. The droplet nozzle can be a mist nozzle that sprays liquid in a mist-like manner, or an inkjet nozzle that forms a row of multiple droplets, or any other type of nozzle. Figure 7C and Figure 7D This example shows that filler nozzle 49 is an inkjet nozzle.

[0095] A fog nozzle can be an externally mixed or internally mixed dual-fluid nozzle that produces fog by colliding liquid and gas, or a spray nozzle that produces fog by discharging compressed liquid from a throttling orifice or by utilizing the Venturi effect.

[0096] The inkjet nozzle can be a piezoelectric or thermal inkjet nozzle, or an inkjet nozzle other than piezoelectric and thermal. The inkjet nozzle can be a large-diameter nozzle 49X with a relatively large diameter ejection orifice 49x for ejecting droplets, or a small-diameter nozzle 49Y with a relatively small diameter ejection orifice 49y for ejecting droplets.

[0097] Figure 7C This represents an example of a large-diameter nozzle, 49X. Figure 7D This illustrates an example of a small-diameter nozzle 49Y. The diameter of the nozzle orifice 49x of the large-diameter nozzle 49X can be within any range of 10 μm or less, 8 μm or less, or 3 μm or less, or outside these ranges. The diameter of the nozzle orifice 49y of the small-diameter nozzle 49Y is the same. The area of ​​the nozzle orifice 49y of the small-diameter nozzle 49Y is smaller than the area of ​​the nozzle orifice 49x of the large-diameter nozzle 49X. When the diameter of the nozzle orifice 49x of the large-diameter nozzle 49X exceeds 10 μm, the diameter of the nozzle orifice 49y of the small-diameter nozzle 49Y can be in the range of 0.01 μm to 10 μm.

[0098] The filler nozzle 49 may be fixed relative to the partition wall 42, or it may be operable relative to the partition wall 42. When multiple filler nozzles 49 are provided in one coating unit 40, at least one filler nozzle 49 may be fixed relative to the partition wall 42, and the remaining at least one filler nozzle 49 may be operable relative to the partition wall 42.

[0099] like Figure 7A and Figure 7B As shown, when the filler nozzle 49 is operable relative to the partition wall 42, the coating unit 40 may include a nozzle actuator 49a that actuates the filler nozzle 49 relative to the partition wall 42. One nozzle actuator 49a may be provided for one filler nozzle 49, or one nozzle actuator 49a may be provided for multiple filler nozzles 49. Figure 7A and Figure 7B Examples representing the former.

[0100] The nozzle actuator 49a may have at least one of the following actuators: a horizontal actuator for horizontally moving the filling fluid nozzle 49, a vertical actuator for vertically moving the filling fluid nozzle 49, and an attitude change actuator for changing the attitude of the filling fluid nozzle 49. When moving the filling fluid nozzle 49 in both the horizontal and vertical directions, the filling fluid nozzle 49 may be directly or indirectly connected to the horizontal actuator, and the horizontal actuator may be directly or indirectly connected to the vertical actuator.

[0101] like Figure 7A and Figure 7B As shown, the coating unit 40 includes a height sensor 47 that measures the height of the substrate W held by the chuck 44. The height sensor 47 measures the height of the upper or lower surface of the substrate W held by the chuck 44. Figure 7A This illustrates an example where a height sensor 47 is positioned above a substrate W held by a chuck 44 to measure the height of the upper surface of the substrate W. The height sensor 47 can be a laser sensor or any other type of sensor.

[0102] The height sensor 47 is an optical, non-contact sensor that detects the position of the substrate W in the vertical direction. When the chuck 44 rotates around its rotation center A1 while holding the substrate W, the substrate W moves relative to the height sensor 47 in the rotation direction Dr of the chuck 44, and the position detected by the height sensor 47 moves relative to the substrate W in the opposite direction to the rotation direction Dr of the chuck 44. Therefore, while the height sensor 47 measures the height of the substrate W, the substrate W and the chuck 44 are rotated more than 360 degrees, and the height of the substrate W is measured over a full circumference.

[0103] By measuring the height of the upper surface of substrate W over its entire circumference, the shape of the upper surface of substrate W can be measured over its entire circumference. For example, if the height of the outer periphery of the upper surface of substrate W is measured over its entire circumference, more specifically, if the height is measured from the end face of substrate W to a position closer to the end face, the shape of the outer periphery of the upper surface of substrate W, including the end face of substrate W, can be measured. Since the shape of the outer periphery of the upper surface of substrate W is measured according to the rotation angle of chuck 44 around the rotation center A1, it is also possible to determine how the shape of the outer periphery of the upper surface of substrate W changes based on the position of substrate W in the circumferential direction.

[0104] The peripheral position sensor 46 is an optical, non-contact sensor that detects the horizontal position of the outer periphery of the substrate W. When the chuck 44 rotates around its rotation center A1 while holding the substrate W, the substrate W moves relative to the peripheral position sensor 46 in the rotation direction Dr of the chuck 44, and the position detected by the peripheral position sensor 46 moves relative to the substrate W in the opposite direction to the rotation direction Dr of the chuck 44. Therefore, while the peripheral position sensor 46 detects the peripheral position of the substrate W, the substrate W and the chuck 44 are rotated more than 360 degrees, and the horizontal position of the outer periphery of the substrate W is detected throughout its entire circumference. Thus, the outer periphery shape of the substrate W can be determined.

[0105] By measuring the outer peripheral shape of the substrate W held by the chuck 44, the eccentricity and direction of the substrate W relative to the rotation center A1 of the chuck 44 can be determined. The orientation of the notch or positioning flat edge relative to the chuck 44 can also be measured. Furthermore, by measuring the outer peripheral position of the substrate W according to the rotation angle of the chuck 44 about the rotation center A1, it is also possible to determine how the outer peripheral position of the substrate W changes in the horizontal direction based on its circumferential position.

[0106] The coating unit 40 includes: a void detector 48, which detects the annular groove WG (refer to) of the bonding substrate W (two substrates W after bonding) held by the chuck 44. Figure 1C The void detector 48 can capture images of the voids within at least one of the filling liquid and the filling material. As long as it can capture images of the voids within the filling liquid and the filling material, the void detector 48 can be an infrared camera or a camera other than an infrared camera. If the void detector 48 is a camera, the image sensor can be either a CCD (Charge Coupled Device) sensor or a CMOS (Complementary Metal Oxide Semiconductor).

[0107] In the case where the void detector 48 is an infrared camera, the coating unit 40 may have a light source 48s that irradiates infrared light onto the outer periphery of the bonding substrate W (see reference). Figure 7A The light source 48s can be configured either within the coating unit 40 or outside the coating unit 40. In the latter case, the light from the light source 48s can be guided into the coating unit 40 via a guide such as an optical fiber. Even without the light source 48s, it is not necessary as long as the presence of voids in the filling liquid and the filling material can be detected.

[0108] Figure 7B This example illustrates the use of a void detector 48 for a single filling fluid nozzle 49. Therefore, in this example, two void detectors 48 are used. However, this is not a limitation; a single void detector 48 can also be used for multiple filling fluid nozzles 49. Figure 7B In the example shown, a void detector 48 is positioned upstream of the filling fluid nozzle 49 in the rotation direction Dr of the chuck 44. The filling fluid nozzle 49 and the void detector 48 can be configured with an angle of less than 45 degrees about the rotation center A1 of the chuck 44.

[0109] The void detector 48 images the interior of the annular groove WG of the bonding substrate W. When at least one of the filling liquid and the filler is located within the annular groove WG, at least one of the filling liquid and the filler is also imaged by the void detector 48. While the void detector 48 images the substrate W, the substrate W and the chuck 44 are rotated more than 360 degrees, and the annular groove WG and the like are imaged around the entire circumference of the substrate W. Therefore, it is possible to check for voids in the filling liquid or filler supplied to the bonding substrate W along the entire circumference of the substrate W. Furthermore, the void detector 48 can be used to observe how the shape of the annular groove WG and the shapes of the filling liquid and filler within the annular groove WG change according to the circumferential position of the substrate W.

[0110] Next, the bonding unit 50 will be described. Unless otherwise specified, the bonding unit 50 described in this specification performs substrate bonding under atmospheric pressure.

[0111] Figure 8A and Figure 8B This is a schematic diagram of the interior of the joint unit 50 viewed horizontally. Figure 8A This indicates the state before the first substrate W1 and the second substrate W2 are joined together. Figure 8B This indicates the state after the first substrate W1 and the second substrate W2 are joined together.

[0112] like Figure 8A as well as Figure 8B As shown, the bonding unit 50 includes: a chamber 51 forming an opening for the passage of a first substrate W1 and a second substrate W2 before and after bonding, and an internal space for the first substrate W1 and the second substrate W2 passing through the opening; a first chuck 54A that holds the first substrate W1 horizontally within the chamber 51; and a second chuck 54B that holds the second substrate W2 horizontally within the chamber 51. The chamber 51 includes: a partition wall 52 forming the internal space and the opening; and a door 53 that opens and closes the opening by moving relative to the partition wall 52.

[0113] The joining unit 50 further includes: a plurality of joining actuators 55, which, while holding the first substrate W1 and the second substrate W2 in the first chuck 54A and the second chuck 54B, move the first chuck 54A and the second chuck 54B relative to each other, thereby joining the first substrate W1 and the second substrate W2; and at least one camera 56, which detects the alignment of the first substrate W1 and the second substrate W2 by taking a picture of at least one of the first substrate W1 and the second substrate W2 before and after joining the first substrate W1 and the second substrate W2.

[0114] The plurality of engagement actuators 55 may include: a horizontal actuator that moves the first chuck 54A and the second chuck 54B relative to each other in a horizontal direction; a vertical actuator that moves the first chuck 54A and the second chuck 54B relative to each other in a vertical direction; and a rotary actuator that rotates the first chuck 54A and the second chuck 54B relative to each other about a vertical line.

[0115] Multiple engagement actuators 55 may include: a reversing actuator that reverses the first substrate W1 held by the first chuck 54A by rotating the first chuck 54A about a horizontal linear path. The reversing actuator can reverse the first substrate W1 held by a chuck other than the first chuck 54A. The reversing actuator can reverse the first substrate W1 outside the engagement unit 50. In the transport robot TR, the manipulator TH (see reference) Figure 3 In cases where the first substrate W1 can be held downward and horizontal (in cases where the robot TH is a vacuum robot or a Bernoulli robot, etc.), the reversing actuator can be part of the transport robot TR.

[0116] At least one camera 56 may include: a first camera 56A, which photographs the first substrate W1 before it is joined with the second substrate W2; a second camera 56B, which photographs the second substrate W2 before it is joined with the first substrate W1; and a third camera 56C, which photographs the first substrate W1 and the second substrate W2 after they are joined. The first camera 56A may photograph the first substrate W1 held by the first chuck 54A, or it may photograph the first substrate W1 held by a chuck other than the first chuck 54A. The same applies to the second camera 56B. The third camera 56C may photograph the joined substrates W (the joined first substrate W1 and the second substrate W2) held by the first chuck 54A or the second chuck 54B, or it may photograph the joined substrates W held by a chuck other than the first chuck 54A and the second chuck 54B. At least one camera 56 may photograph at least one of the first substrate W1 and the second substrate W2 outside of the joining unit 50.

[0117] The first camera 56A and the second camera 56B are alignment cameras used to confirm and adjust the alignment of the first substrate W1 and the second substrate W2 before bonding. The third camera 56C is an inspection camera used to confirm the alignment of the first substrate W1 and the second substrate W2 after bonding. The inspection camera is an infrared camera that generates electronic data of still or moving images by converting infrared light into electrical signals. The alignment camera can be an infrared camera or a visible light camera that generates electronic data of still or moving images by converting visible light into electrical signals.

[0118] Next, the grinding unit 60 will be described.

[0119] Figure 9A This is a schematic diagram of the interior of the grinding unit 60 viewed horizontally. Figure 9B This is a schematic diagram of the interior of the grinding unit 60 as viewed from directly above.

[0120] like Figure 9A and Figure 9B As shown, the grinding unit 60 includes: a chamber 61 forming an opening for the bonding substrates W, i.e., the first substrate W1 and the second substrate W2 after bonding, to pass through, and an internal space for the bonding substrates W through the opening; a chuck 64 holding the bonding substrates W horizontally within the chamber 61; and an electric motor 65 that rotates the bonding substrates W about a vertical rotation center A1 passing through the central portion of the bonding substrates W held by the chuck 64 by rotating the chuck 64. The chamber 61 includes: a partition wall 62 forming the internal space and the opening; and a door 63 that opens and closes the opening by moving relative to the partition wall 62.

[0121] The grinding unit 60 further includes: a grinding stone 66 pressed against the upper surface of the bonding substrate W held by the chuck 64; a horizontal, circular grinding wheel 67 holding the grinding stone 66; an electric motor 68 that rotates the grinding stone 66 and the grinding wheel 67 about a vertical center of rotation passing through the central portion of the grinding wheel 67; and a lifting actuator 69 that moves the grinding stone 66 and the grinding wheel 67 vertically. While the chuck 64 and the grinding wheel 67 are rotated, and the grinding stone 66 contacts the upper surface of the bonding substrate W, the entire area of ​​the upper surface of the bonding substrate W is ground by the grinding stone 66.

[0122] Next, the electrical structure of the substrate bonding device 1 will be described.

[0123] Figure 10 This is a block diagram showing the electrical structure of the substrate bonding apparatus 1. The substrate bonding apparatus 1 includes a control device 3 that controls the electrical and electronic equipment included in the substrate bonding apparatus 1. The control device 3 controls the substrate bonding apparatus 1 to operate as described below. In other words, the control device 3 is programmed to perform the operations described below.

[0124] The control device 3 includes at least one computer. The computer includes a computer body 3a and peripheral devices 3d connected to the computer body 3a. The computer body 3a includes a CPU 3b (central processing unit) that executes various commands and a memory 3c that stores information. The peripheral devices 3d include: a recorder 3e that stores information such as a program P that should be transmitted and received between the computer and the memory 3c; a reader 3f that reads information from a removable medium RM; and a communication device 3g that communicates with other devices such as the host computer HC. The memory 3c and the recorder 3e are examples of storage devices that store information that should be transmitted and received between the computer and the CPU 3b.

[0125] The control device 3 is connected to the input device 3h and the display device 3i. When users, maintenance personnel, or other operators input information into the substrate bonding assembly 1, they operate the input device 3h. The information is displayed on the screen of the display device 3i. The input device 3h can be any one of a keyboard, a pointing device, or a touch panel, or other devices. A touch panel display that functions as both the input device 3h and the display device 3i can be installed on the substrate bonding assembly 1.

[0126] CPU 3b executes program P stored in recorder 3e. Program P in recorder 3e can be pre-installed in control device 3, or it can be transferred to recorder 3e from removable medium RM via reader 3f, or it can be transferred to recorder 3e from external devices such as host computer HC via communication device 3g.

[0127] Memory 3c is a volatile memory that retains its storage only when powered. Recorder 3e and removable medium RM are non-volatile memories that retain their storage even when not powered. Recorder 3e is, for example, a magnetic storage device such as a hard disk drive. Removable medium RM is, for example, a semiconductor memory such as a compact disc or a memory card. Removable medium RM is an example of a computer-readable recording medium that records a program P. Removable medium RM is a non-transitory tangible recording medium.

[0128] Recorder 3e stores multiple process RCs. A process RC specifies the processing content, processing conditions, and processing procedure for substrate W. The multiple process RCs differ in at least one of the processing content, processing conditions, and processing procedure for substrate W. Control device 3 controls substrate bonding device 1 to process substrate W according to the process RCs specified by host computer HC. Control device 3 is programmed to execute the processes described later.

[0129] The process RC includes: coating amount (the total amount of filler liquid supplied to one substrate W), coating start position (the position where the supply of filler liquid to substrate W begins), and coating end position (the position where the supply of filler liquid to substrate W ends). That is, the coating amount, etc., are specified by the process RC. The path traversed by the filler liquid nozzle 49 when it is moved is also included in the process RC. The user can change the coating amount, etc., by editing the process RC. The process RC can be edited via the user operation input device 3h, or via a device other than the substrate bonding device 1, such as a personal computer. In the latter case, the edited process RC is transmitted to the control device 3 via the communication device 3g.

[0130] Next, the application of the filler liquid to the substrate W will be described. First, the shape of the substrate W will be described, and then the application of the filler liquid to the substrate W will be described.

[0131] Figure 11A This is a schematic cross-sectional view of the outer periphery of the substrate W. Figure 11B This is a schematic diagram of the interior of the coating unit 40 as viewed from directly above. Figure 11C This is a schematic cross-sectional view showing the state of supplying filling liquid FL to the annular groove WG formed between the outer peripheries of the two bonded substrates W. Figure 11D This is a schematic cross-sectional view showing the state of the gaps V1 and V2 between the two substrates W after bonding, as detected by the void detector 48.

[0132] As described above, after the two substrates W are bonded together, a filler liquid FL is applied to the outer periphery of the bonded substrates W. The outer periphery of the substrates W is also referred to as the beveled portion. Figure 11A This example illustrates that the cross-section of the outer periphery of the substrate W is semi-circular or parabolic. The cross-section of the outer periphery of the substrate W can be a shape other than a trapezoidal or parabolic shape. Hereinafter, the state where the surface and back surface of the substrate W are horizontal will be described.

[0133] The outer surface of substrate W includes: a bonding surface WA that contacts other substrates W, a non-bonding surface WN that does not contact other substrates W, and an outermost front end WE on the outer surface of substrate W. The front end WE of substrate W is an annular line or surface connecting the outer periphery of the bonding surface WA to the outer periphery of the non-bonding surface WN. The end face of substrate W is the area encompassing a defined range of the front end WE of substrate W.

[0134] The bonding surface WA of substrate W includes: a horizontal and flat circular flat portion F1, and an annular outer peripheral portion O1 extending from the outer periphery of the flat portion F1 toward the front end WE in a manner that decreases as it approaches the front end WE. The non-bonding surface WN of substrate W includes: a horizontal and flat circular flat portion F2, and an annular outer peripheral portion O2 extending from the outer periphery of the flat portion F2 toward the front end WE in a manner that increases as it approaches the front end WE.

[0135] The flat portion F1 of the bonding surface WA corresponds to the device formation region for forming the device. The flat portion F1 of the bonding surface WA is parallel to the flat portion F2 of the non-bonding surface WN. The center of the flat portion F1 of the bonding surface WA is located on the center line of the substrate W. The center of the flat portion F2 of the non-bonding surface WN is also located on the center line. The diameter of the flat portion F1 of the bonding surface WA is equal to or approximately equal to the diameter of the flat portion F2 of the non-bonding surface WN. When the outer peripheral cross-section of the substrate W is semi-circular or parabolic, the cross-sections of the outer peripheral portions O1 and O2 are arc-shaped. When the outer peripheral cross-section of the substrate W is trapezoidal, the cross-sections of the outer peripheral portions O1 and O2 are straight.

[0136] In Figure 11A When two substrates W are bonded as shown, an annular groove WG is formed on the outer periphery of the two bonded substrates W, with openings at the end faces of the two substrates W. The annular groove WG is formed between the two substrates W through the outer periphery of the bonded substrates W. The annular groove WG is continuous along the entire circumference of the bonded substrates W. The thickness direction of the two bonded substrates W corresponds to the width direction of the annular groove WG, and the radial direction of the two bonded substrates W (the direction orthogonal to the centerline of the substrates W) corresponds to the depth direction of the annular groove WG. The depth of the annular groove WG increases continuously or in stages as it approaches the center of the annular groove WG in the width direction.

[0137] As described above, after bonding the two substrates W together, a grinding stone 66 (see reference) is used. Figure 9A The bonded substrate W, i.e., one of the two bonded substrates W, is thinned. The thickness of the outer periphery of substrate W decreases as it approaches the end face of substrate W. Near the end face of substrate W, the outer peripheries of the two bonded substrates W separate from each other, forming a gap equivalent to an annular groove WG. When there is no filler FS in the annular groove WG (refer to...), Figure 11D When grinding and bonding substrates W under the condition of grinding stone 66, force is applied to the outer periphery of substrate W, and sometimes the outer periphery of one substrate W deflects toward the outer periphery of the other substrate W. To alleviate this situation, it is necessary to supply the annular groove WG with a filling liquid FL that changes to a solid or semi-solid filler FS.

[0138] When supplying filling liquid FL to the annular groove WG of the bonding substrate W, as Figure 11B As shown, the transport robot TR (refer to...) Figure 3 The bonding substrate W is moved into the coating unit 40 and held horizontally in the chuck 44. Thus, the substrate W is held horizontally with the surface of the substrate W, which serves as the bonding surface WA, facing upwards. In this state, while rotating the substrate W using the chuck 44, the filling liquid nozzle 49 sprays the filling liquid FL toward the annular groove WG of the bonding substrate W.

[0139] Filler liquid FL sprayed from filler nozzle 49 is applied to the inner surface of annular groove WG. Figure 11C This example illustrates that the filler nozzle 49 is an inkjet nozzle. In this example, multiple droplets of filler liquid FL ejected from the filler nozzle 49 are dispersed in approximately the same direction toward the annular groove WG of the bonding substrate W. These droplets enter the annular groove WG and collide with the bonding substrate W within it. As a result, the filler liquid FL is coated onto the inner surface of the annular groove WG.

[0140] Droplets of filler liquid FL applied to the bonding substrate W remain at or near the point of impact with the bonding substrate W due to the viscosity of the filler liquid FL and the force acting on the filler liquid FL from the bonding substrate W. Subsequent droplets of filler liquid FL collide with at least one of the inner surface of the annular groove WG and the filler liquid FL adhering to the inner surface of the annular groove WG, remaining at or near the point of impact. Through repeated occurrences of this phenomenon, the filler liquid FL gradually reduces the space within the annular groove WG, i.e., the space between the outer peripheries of the two bonded substrates W.

[0141] The filling liquid FL within the annular groove WG transforms into a solid or semi-solid filler FS within the annular groove WG. When grinding of the bonding substrate W begins, if the filling liquid FL transforms into filler FS, the transformation can occur either during the ejection of filling liquid FL from the filling liquid nozzle 49 or after the ejection of filling liquid FL from the filling liquid nozzle 49 has ceased. In either case, a process that induces or promotes the transformation from filling liquid FL to filler FS can be performed.

[0142] From the moment the filling fluid FL is ejected from the filling fluid nozzle 49 until the end of the ejection process, the filling fluid nozzle 49 can be kept stationary or continuously moving. The following periods are possible: a period during which the filling fluid nozzle 49 is stationary while ejecting the filling fluid FL, and a period during which the filling fluid nozzle 49 is moving while ejecting the filling fluid FL.

[0143] The radial distance from the rotation center A1 of the bonding substrate W to the outer periphery of the bonding substrate W can vary depending on the angle about the rotation center A1 of the bonding substrate W. The height of the outer periphery of the bonding substrate W can also vary depending on the angle about the rotation center A1 of the bonding substrate W. Therefore, the position of the annular groove WG can vary in at least one of the radial and vertical directions depending on the angle about the rotation center A1 of the bonding substrate W.

[0144] like Figure 11C As shown, the control device 3 can move the nozzle actuator 49a to move the filling liquid nozzle 49 according to the change in the position of the annular groove WG in at least one of the radial and vertical directions, thereby reducing the change in distance from the filling liquid nozzle 49 to the annular groove WG of the bonding substrate W. In this case, the filling liquid nozzle 49 can be started to spray the filling liquid FL toward the rotating bonding substrate W after the position change of the annular groove WG is measured throughout the entire circumference of the bonding substrate W, or the filling liquid nozzle 49 can be sprayed toward the rotating bonding substrate W while the position change of the annular groove WG is measured.

[0145] The peripheral position sensor 46, height sensor 47, and void detector 48 are examples of position detectors for detecting the position of the outer periphery of the bonding substrate W. Changes in the position of the annular groove WG can be detected by one or more of the peripheral position sensor 46, height sensor 47, and void detector 48. The void detector 48 can also detect changes in the position of the annular groove WG in the radial and vertical directions by detecting changes in the angle of the shape of the annular groove WG relative to the rotation center A1 around the bonding substrate W.

[0146] Figure 11B This example illustrates how, while measuring the position and shape changes of the annular groove WG using a void detector 48, a filling liquid nozzle 49 is directed to spray filling liquid FL towards a rotating bonding substrate W. In this example, the void detector 48 is positioned upstream of the filling liquid nozzle 49 in the rotation direction Dr of the bonding substrate W. Since the difference in rotation angle between the void detector 48 and the filling liquid nozzle 49 (the difference in angle around the rotation center A1 of the bonding substrate W) and the rotation speed of the bonding substrate W are known, the filling liquid nozzle 49 can be moved relative to the bonding substrate W based on their position changes and directions of change, as well as the amount and direction of those changes.

[0147] Not only the position of the annular groove WG, but also its shape may change depending on the angle around the rotation center A1 of the bonding substrate W. When the changes in the position and shape of the annular groove WG are measured by the void detector 48, the flow rate of the filling liquid FL ejected from the filling liquid nozzle 49 (the amount of filling liquid FL ejected from the filling liquid nozzle 49 per unit time) can be varied according to these changes. This reduces the radial distance variation from the rotation center A1 of the bonding substrate W to the outer end of the filling liquid FL within the annular groove WG. Regardless of whether the changes in the position and shape of the annular groove WG are measured, the control device 3 can vary the flow rate of the filling liquid FL.

[0148] When applying filler liquid FL to multiple bonding substrates W, the position of the annular groove WG sometimes changes uniformly among these bonding substrates W. Therefore, the control device 3 can move the filler liquid nozzle 49 by the nozzle actuator 49a according to the positional changes of the annular groove WG on other bonding substrates W. That is, the control device 3 can store measurement data D1 when measuring the positional changes of the annular groove WG on other bonding substrates W, and move the filler liquid nozzle 49 by the nozzle actuator 49a according to the measurement data D1. Not limited to this, the control device 3 can also measure the changes in the position and shape of the annular groove WG by the void detector 48, etc., whenever the bonding substrate W held by the chuck 44 changes.

[0149] Thus, filler liquid FL is applied to the inner surface of the annular groove WG. Any defects in the application can be detected by observing the annular groove WG using a void detector 48 after the supply of filler liquid FL has been stopped. Figure 11D As shown, the void detector 48 is capable of detecting voids V1 within the filling liquid FL or filler FS in the annular groove WG of the bonding substrate W held by the chuck 44. The void detector 48 can be configured to detect voids V2 between the bonding surfaces WA1 and WA2. When detecting voids V2, the void detector 48 can be moved above or below the bonding substrate W held by the chuck 44, or other void detectors 48 can be positioned above or below the bonding substrate W held by the chuck 44.

[0150] When two substrates W are bonded together, a gap equivalent to an annular groove WG is formed between the outer peripheries of the two substrates W. When grinding two substrates W without a filler FS in the annular groove WG, force is sometimes applied to the outer periphery of the substrates W from the grinding stone, causing the outer periphery of the substrates W to deflect towards the annular groove WG. By placing a filler FS in the annular groove WG, this deflection can be mitigated. The gap V1 within the filler FS (see reference...) Figure 11D This could be the cause of stress concentration in the filler FS during the grinding of two substrates W. By supplying droplets of filler liquid FL to the annular groove WG, the voids V1 can be reduced or decreased.

[0151] After filling the annular groove WG with filler liquid FL, the bonding substrate W is ground. At the start of grinding the bonding substrate W, the filler liquid FL in the annular groove WG changes into a solid or semi-solid filler FS. Using a grinding stone 66 (see reference...) Figure 9A When grinding and bonding the substrate W, i.e., one of the two bonded substrates W, the outer periphery of the bonded substrate W is supported by the filler FS. Therefore, edge chipping due to end defects in the thinned substrate W and the associated particle formation can be prevented or reduced. As a result, particles adhering to the device can be reduced, and the device yield can be improved.

[0152] Next, the effects of this embodiment will be explained.

[0153] In this embodiment, while rotating the bonding substrate W, multiple droplets of filler liquid are sprayed towards the annular groove WG formed between the outer peripheries of the two bonded substrates W. This allows filler liquid to be supplied to the annular groove WG. Furthermore, by controlling the rotation angle of the chuck 44 holding the bonding substrate W, the range of filler liquid supplied to the annular groove WG can be controlled. The filler liquid can be a solid or semi-solid filler. Therefore, the relative movement of the outer peripheries of the two bonded substrates W can be restricted by the filler. Moreover, because multiple droplets of filler liquid are sprayed, the amount of filler liquid supplied to the annular groove WG can be precisely controlled compared to the case of continuous spraying of filler liquid.

[0154] In this embodiment, the filler nozzle 49, which serves as the inkjet nozzle, intermittently ejects droplets of filler liquid. Multiple droplets of filler liquid ejected from the filler nozzle 49 disperse toward the annular groove WG in the same or nearly the same direction. Therefore, compared to the case where multiple droplets of filler liquid disperse in various directions, the position of the supplied filler liquid can be controlled with high precision.

[0155] In this embodiment, the position of the outer periphery of the bonding substrate W held by the chuck 44 is detected, and the nozzle actuator 49a moves the filling liquid nozzle 49 according to the detected position. As the position of the outer periphery of the bonding substrate W changes, the filling liquid nozzle 49 moves in at least one of the horizontal and vertical directions, thus reducing the change in distance from the filling liquid nozzle 49 to the bonding substrate W caused by the rotation of the bonding substrate W. Therefore, the position of the supplied filling liquid can be controlled with high precision. When the amount of filling liquid FL ejected from the filling liquid nozzle 49 per unit time changes according to the detected position, the radial distance change from the rotation center A1 of the bonding substrate W to the outer end of the filling liquid FL in the annular groove WG can be reduced.

[0156] In this embodiment, the nozzle actuator 49a moves the filling liquid nozzle 49 while detecting the position of the outer periphery of the bonding substrate W, rather than after detecting the position of the outer periphery of the bonding substrate W. Therefore, compared to the case where the nozzle actuator 49a moves the filling liquid nozzle 49 after the position detection of the outer periphery of the bonding substrate W is completed and without performing the detection, the time until the supply of filling liquid to the annular groove WG ends can be shortened.

[0157] In this embodiment, while the chuck 44 holds the bonding substrate W, voids in the filling liquid or filling material within the annular groove WG are detected by the void detector 48. This allows for the simultaneous supply of filling liquid to the annular groove WG and detection of voids within the filling liquid or filling material. Furthermore, the void detector 48 can be configured to detect not only voids in the filling liquid or filling material but also voids between the bonding surfaces WA of the two bonded substrates W. Therefore, compared to detecting voids between the bonding surfaces WA of the two substrates W after the bonding substrate W has been moved from the chuck 44, the time until the detection of voids is completed can be shortened.

[0158] In this embodiment, a coating unit 40 is provided in the substrate bonding apparatus 1 that bonds two substrates W. The coating unit 40 applies a filler liquid to the two substrates W bonded by the bonding unit 50. As described above, the coating unit 40 rotates the bonded substrates W while spraying multiple droplets of filler liquid toward the annular groove WG formed between the outer peripheries of the two bonded substrates W. Therefore, not only can the time from bonding the two substrates W to supplying filler liquid to the bonded substrates W be shortened, but the amount of filler liquid supplied to the annular groove WG can also be precisely controlled.

[0159] In this embodiment, not only the bonding unit 50 and the coating unit 40, but also the polishing unit 60, which polishes the bonding substrate W coated with the filler liquid, is provided in the substrate bonding apparatus 1. Therefore, the time from bonding the two substrates W to polishing the bonded substrates W can be shortened. The filler liquid applied to the bonding substrate W is a solid or semi-solid filler. Therefore, by applying force from the polishing stone 66, the deflection of the outer periphery of the substrate W can be suppressed, and the bonding substrate W can be polished.

[0160] Next, other implementation methods will be described.

[0161] like Figure 12A As shown, the coating unit 40 can be integrated with the bonding unit 50, rather than with the pre-bonding alignment device.

[0162] Figure 12A The coating unit 40 shown includes Figure 8A and Figure 8BThe structure of the bonding unit 50 is shown. Therefore, the coating unit 40 includes a first chuck 54A, a second chuck 54B, and a bonding actuator 55, etc. The first chuck 54A, the second chuck 54B, and the chuck 44, etc., are disposed within the chamber 41 of the coating unit 40.

[0163] When the coating unit 40 and the bonding unit 50 are integrated, when the first substrate W1 held by the first chuck 54A and the second substrate W2 held by the second chuck 54B are bonded, the first substrate W1 and the second substrate W2 are held by the second chuck 54B with the first substrate W1 positioned above the second substrate W2. The bonding actuator 55 causes the second chuck 54B to move horizontally between a shooting position (central position), a bonding position (left side position), and a receiving position (right side position). The shooting position is where the third camera 56C takes a picture of the bonding substrate W held by the second chuck 54B. The bonding position is where the first substrate W1 held by the first chuck 54A and the second substrate W2 held by the second chuck 54B are bonded. The receiving position is where the second chuck 54B or the chuck 44 receives the bonding substrate W.

[0164] The adsorption surface of the chuck 44 that contacts the bonding substrate W faces downwards. The coating unit 40 includes a chuck lifting actuator 44a that moves the chuck 44 vertically. The chuck lifting actuator 44a moves the chuck 44 between the receiving position of the second chuck 54B or the chuck 44 receiving the substrate W and the coating position of applying filler liquid to the bonding substrate W held by the chuck 44. Figure 12A The position is vertically moved between the indicated positions. The application position is above the receiving position. The receiving position of chuck 44 is above the receiving position of the second chuck 54B.

[0165] When the second chuck 54B and chuck 44 are in the receiving position, the chuck 44 receives the bonding substrate W held by the second chuck 54B. The chuck 44 rises from the receiving position to the coating position while holding the bonding substrate W. Then, filling liquid is supplied to the annular groove WG of the bonding substrate W held by the chuck 44. At the start of filling liquid supply, the second chuck 54B can be in the receiving position or retracted from it.

[0166] Except that the bonding substrate W is positioned below the chuck 44, the filling liquid is supplied to the annular groove WG in the same manner as described above. Alternatively, it can be supplied by... Figure 7A and Figure 7B At least one of the peripheral position sensor 46, height sensor 47, and void detector 48 shown is used to detect the position of the outer periphery of the bonding substrate W held by the chuck 44. After the filling liquid is supplied to the annular groove WG, the transfer robot TR (see reference) Figure 3The substrate W can be accepted from a chuck 44 located at a position within the range from the acceptance position to the coating position, or from a second chuck 54B located at a position within the range from the acceptance position to the shooting position.

[0167] like Figure 12B As shown, after the filling liquid FL is supplied to the annular groove WG, the bonding completed substrate W held by the second chuck 54B can be photographed by the third camera 56C, which acts as an infrared camera. Specifically, after the bonding substrate W held by the chuck 44 is received by the second chuck 54B, the second chuck 54B is moved from the receiving position to the photographing position. Then, the bonding completed substrate W held by the second chuck 54B can be photographed by the third camera 56C. In this case, not only the gap V2 between the bonding surfaces WA1 and WA2, but also the gap V1 in the filling liquid FL in the annular groove WG or the filling body FS can be detected by the third camera 56C.

[0168] exist Figure 12A In the structure shown, not only the chuck 44 and the filler nozzle 49, but also the chamber 41 of the coating unit 40 houses the first chuck 54A and the second chuck 54B of the bonding unit 50. Therefore, compared to the case where a dedicated chamber 51 is provided for the bonding unit 50, the substrate bonding apparatus 1 can be miniaturized. Furthermore, since the filling liquid is supplied to the bonding substrate W held by the chuck 44, which is different from the first chuck 54A and the second chuck 54B, the filler nozzle 49 can be moved away from the first chuck 54A and the second chuck 54B, making it difficult for the filling liquid to adhere to the first chuck 54A and the second chuck 54B.

[0169] exist Figure 12B In the structure shown, the void detector 48 detects not only the gap between the bonding surfaces WA of the two substrates W after bonding, but also the voids within the filling liquid or filling material in the annular groove WG. In other words, the void detector 48, which detects the gap between the two substrates W, can also be used as a void detector 48 to detect voids within the filling liquid or filling material. Therefore, it is not necessary to provide a dedicated void detector 48 that only detects voids within the filling liquid or filling material in the annular groove WG.

[0170] like Figure 13 As shown, the filler liquid can be applied only to a portion of the circumferential direction of the substrate W, instead of applying the filler liquid to the entire circumference of the substrate W. Figure 13 The area enclosed by double-dotted lines indicates the area where the filler liquid is applied. In this example, the filler liquid is applied only to four areas separated circumferentially along the substrate W.

[0171] Transistors and other devices are formed on the surface of a substrate W, which corresponds to the device formation surface. Both the device region and the non-device region are regions within the surface of the substrate W. Figure 13 In the diagram, the outer edge of the device region is represented by a thick line. The device region is the area containing devices or patterns such as transistors. The non-device region is the area where no devices or patterns exist. The non-device region is the ring-shaped area surrounding the device region.

[0172] The shortest distance from the outer periphery of the substrate W to the outer edge of the device region sometimes varies depending on the position on the outer periphery of the substrate W. If this shortest distance is relatively short, it is easier to grind the substrate W with a grinding stone 66 (see reference 66) during the bonding process. Figure 9A A relatively large force is applied to the device located at the end of the device region. If a crack or notch generated on the outer periphery of the bonding substrate W during grinding reaches the device located at the end of the device region, that device (including the cracked device) becomes defective. The shorter this minimum distance, the easier it is for device defects to occur. Figure 13 As shown, the filler liquid can be applied only to several relatively short areas (the areas enclosed by the double-dotted lines). This prevents the application of large forces to devices located at the ends of the device region and reduces the time required for filling liquid application compared to applying the filler liquid to the entire circumference of the substrate W.

[0173] The filling liquid nozzle 49 can continuously spray filling liquid in a manner that forms a continuous liquid column from the filling liquid nozzle 49 to the substrate W, or it can continuously spray filling liquid in a manner that forms a continuous liquid column from the filling liquid nozzle 49 to the substrate W after spraying multiple droplets of filling liquid toward the substrate W. In the latter case, both a droplet nozzle that sprays multiple droplets of filling liquid toward the substrate W and a liquid column nozzle that continuously sprays filling liquid in a manner that forms a continuous liquid column from the filling liquid nozzle 49 to the substrate W can be provided.

[0174] After multiple droplets of filler liquid are sprayed toward the substrate W, if the filler liquid is continuously sprayed in a manner that forms a continuous liquid column from the filler liquid nozzle 49 to the substrate W, the position of the filler liquid supply can be precisely controlled initially, and then the filler liquid can be supplied at high speed. Therefore, compared with the case of multiple droplets of filler liquid being sprayed from beginning to end, the time until the filler liquid supply is completed can be shortened.

[0175] The filling fluid nozzle 49 can be made by Figure 7C and Figure 7D The diagram shows a large-diameter nozzle 49X and a small-diameter nozzle 49Y. In this configuration, droplets of filler liquid ejected from the nozzle 49y of the small-diameter nozzle 49Y can be supplied to the bottom (deepest part) of the annular groove WG, i.e., a location difficult for the filler liquid to reach. Then, droplets of filler liquid ejected from the nozzle 49x of the large-diameter nozzle 49X can be supplied to the annular groove WG. This prevents voids (cavities) from forming at the bottom of the annular groove WG and shortens the time required for filler liquid application.

[0176] The grinding unit 60 can be omitted from the substrate bonding apparatus 1. The coating unit 40 can also be omitted from the substrate bonding apparatus 1. That is, the coating unit 40 can be a device that is disposed outside the outer wall 1a of the substrate bonding apparatus 1 and is different from the substrate bonding apparatus 1.

[0177] The substrate bonding device 1 is not limited to a device for bonding two circular substrates W, but can also be a device for bonding two polygonal substrates W.

[0178] Two or more of the structures described above can be combined. Two or more of the processes described above can also be combined.

[0179] The embodiments of the present invention have been described in detail, but these are merely specific examples used to clarify the technical content of the present invention, and the present invention should not be limited to these specific examples to explain the present invention. The spirit and scope of the present invention are defined only by the appended claims.

[0180] This application claims priority based on Japanese Patent Application No. 2023-188940, filed on November 2, 2023, the entire contents of which are incorporated herein by reference.

Claims

1. A coating unit, characterized in that, Include: A chuck that holds the two joined substrates (i.e., the bonding substrates) while rotating about an axis orthogonal to the main surface of the bonding substrates and passing through the center of the main surface; and A filler nozzle supplies the filler liquid to an annular groove formed between the outer peripheries of the two joined substrates by spraying multiple droplets of filler liquid onto the bonding substrates held by the chuck, wherein the filler liquid is a solid or semi-solid filler.

2. The coating unit according to claim 1, characterized in that, The filling fluid nozzle is an inkjet nozzle that causes multiple droplets of the filling fluid to fly towards the annular groove in approximately the same direction.

3. The coating unit according to claim 1 or 2, characterized in that, The coating unit further includes: A position detector that detects the position of the outer periphery of the bonding substrate held by the chuck; and A nozzle actuator that moves the filling fluid nozzle according to the position of the outer periphery detected by the position detector.

4. The coating unit according to claim 3, characterized in that, The coating unit further includes: a control device that performs at least one of position control and flow control, wherein... The position control is as follows: while the position detector detects the position of the outer peripheral portion, the nozzle actuator moves the filling liquid nozzle according to the position of the outer peripheral portion detected by the position detector; The flow control is as follows: while the position detector detects the position of the outer periphery, the amount of filling liquid ejected from the filling liquid nozzle per unit time is changed according to the position of the outer periphery detected by the position detector.

5. The coating unit according to any one of claims 1 to 4, characterized in that, The coating unit further includes a void detector, which detects voids in the filling liquid or filler within the annular groove and voids between the bonding surfaces of the two substrates after bonding, while the chuck holds the bonding substrates.

6. The coating unit according to any one of claims 1 to 5, characterized in that, The filling fluid nozzle comprises: A large-diameter nozzle, which sprays multiple droplets of the filling liquid from an injection port toward the bonding substrate held by the chuck; and A small-diameter nozzle sprays multiple droplets of the filling liquid from an injection port with an area smaller than that of the large-diameter nozzle onto the bonding substrate held by the chuck.

7. A substrate bonding apparatus, characterized in that, The substrate bonding device has: A bonding unit that bonds two substrates together; as well as A coating unit applies a filler liquid to the two substrates (i.e., the bonded substrates) bonded by the bonding unit, wherein the filler liquid is a solid or semi-solid filler. The coating unit includes: A chuck that holds the bonding substrate while rotating about an axis orthogonal to the main surface of the bonding substrate and passing through the center of the main surface; and A filler nozzle supplies the filler liquid to an annular groove formed between the outer peripheries of the two joined substrates by spraying multiple droplets of the filler liquid onto the joining substrates held by the chuck.

8. The substrate bonding apparatus according to claim 7, characterized in that, The joining unit comprises: The first chuck and the second chuck respectively hold the two substrates before they are joined; as well as An engagement actuator, by moving the first chuck and the second chuck relative to each other, brings the two substrates held by the first chuck and the second chuck into contact. The coating unit further includes a chamber that houses the chuck, the filling fluid nozzle, the first chuck, and the second chuck.

9. The substrate bonding apparatus according to claim 7 or 8, characterized in that, The bonding unit further includes a void detector, which detects the void between the bonding surfaces of the two substrates after bonding, as well as the void in the filling liquid or filling body within the annular groove.

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