Coating unit and substrate bonding apparatus provided with the same

Abstract

The coating unit includes: a chuck that holds a substrate having a bonding surface bonded to another substrate and rotates around an axis orthogonal to a main surface of the substrate and passing through the center of the main surface; and a filling liquid nozzle that discharges a filling liquid of a filling body that changes to a solid or semi-solid state toward the bonding surface of the substrate held by the chuck, thereby supplying the filling liquid only to the peripheral portion of the bonding surface of the substrate.

Description

Technical Field

[0001] This invention relates to a coating unit and a substrate bonding apparatus having the coating unit, wherein the coating unit coats one or both of two substrates before bonding with a filler liquid. The 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 magneto-optical discs, substrates for photomasks, ceramic substrates, and substrates for solar cells. Background Technology

[0002] Patent Document 1 discloses an end condition confirmation device capable of determining whether a protective member formed on the outer peripheral end of a substrate has internal defects. Paragraph 0089 of Patent Document 1 describes: "A coating liquid for a protective member is filled into the space between the beveled edge of a single substrate w1 and the beveled edge of a single substrate w2. The protective member w4 is formed by hardening the filled coating liquid."

[0003] Existing technical documents

[0004] Patent documents

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

[0006] The technical problem that the invention aims to solve

[0007] In the end-state confirmation device described in Patent Document 1, after two substrates are bonded together, a coating liquid is filled into the space between the outer peripheries of the two substrates. The width of the space between the outer peripheries of the bonded two substrates (the length of the space in the thickness direction of the two substrates) decreases as it approaches the bottom of the space. Therefore, the coating liquid has difficulty reaching the bottom side of the space.

[0008] At least one embodiment of the present invention provides a coating unit and a substrate bonding apparatus having the coating unit, which is capable of distributing a filling liquid at a deeper position in the space between the outer peripheries of two bonded substrates.

[0009] Solution to the problem

[0010] One embodiment of the present invention provides a coating unit comprising: a chuck that holds a substrate having a mating surface that bonds with other substrates and rotates around an axis orthogonal to the main surface of the substrate and centered on the center of the main surface; and a filler nozzle that dispenses a filler liquid, which is in a solid or semi-solid state, toward the mating surface of the substrate held by the chuck, thereby supplying the filler liquid only to the outer periphery of the mating surface of the substrate. The substrate comprises two parallel planes, namely a surface and a back surface. The main surface of the substrate can be either the surface or the back surface of the substrate. One of the surface and the back surface of the substrate is a mating surface that bonds with other substrates, and the other surface and the back surface of the substrate is a non-matting surface that does not bond with other substrates.

[0011] In the above embodiments, at least one of the following features may also be added to the coating unit.

[0012] The aforementioned bonding surface of the substrate includes: a flat portion that bonds to other substrates; and an outer peripheral portion that is recessed from the outer periphery of the flat portion toward a non-bonding surface of the substrate opposite to the bonding surface.

[0013] The aforementioned filling fluid nozzle is a droplet nozzle that sprays multiple droplets of the filling fluid toward the outer periphery of the bonding surface of the substrate held by the chuck, thereby supplying the filling fluid only to the outer periphery of the bonding surface of the substrate.

[0014] The aforementioned droplet nozzle includes: a large-diameter nozzle that sprays a plurality of droplets of the filling liquid from a spray port toward the outer periphery of the mating surface of the substrate held by the chuck; and a small-diameter nozzle that sprays a plurality of droplets of the filling liquid from a spray port with an area smaller than the spray port of the large-diameter nozzle toward the outer periphery of the mating surface of the substrate held by the chuck.

[0015] The coating unit further includes: a position detector that detects the position of the outer periphery of the 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.

[0016] The coating unit further includes a control device that performs at least one of the following controls based on the position of the outer periphery of another substrate detected by the position detector: position control, which moves the filling liquid nozzle by the nozzle actuator; and flow control, which detects the position of the outer periphery of the substrate held by the chuck by the position detector, and changes the amount of filling liquid sprayed from the filling liquid nozzle per unit time based on the position of the outer periphery detected by the position detector.

[0017] Another embodiment of the present invention provides a substrate bonding apparatus comprising: a coating unit that coats a filler liquid that changes into a solid or semi-solid state onto a substrate; and a bonding unit that bonds two substrates after at least one of them has been coated with the filler liquid; the coating unit includes: a chuck that holds a substrate having a bonding surface that bonds with other substrates and rotates about an axis orthogonal to the main surface of the substrate and passing through the center of the main surface; and a filler liquid nozzle that dispenses the filler liquid toward the bonding surface of the substrate held by the chuck, thereby supplying the filler liquid only to the outer periphery of the bonding surface of the substrate. Attached Figure Description

[0018] Figure 1A This is a schematic diagram showing an example of the appearance of the two substrates before and after they are joined.

[0019] Figure 1B This is a schematic diagram showing an example of a cross-section of two substrates before and after they are joined.

[0020] Figure 1C This is a schematic diagram showing an example of a cross-section of a substrate before and after the filling liquid is supplied to the bonding surface of the substrate.

[0021] Figure 1D This is a schematic diagram showing an example of cross-sections of two substrates before and after they have been thinned, which are already joined together.

[0022] Figure 2 This is a process diagram illustrating a substrate bonding method according to an embodiment of the present invention.

[0023] Figure 3 This is a schematic top view of a substrate bonding apparatus according to an embodiment of the present invention.

[0024] Figure 4A This is a horizontal schematic diagram of the interior of the positioner before activation.

[0025] Figure 4B This is a schematic diagram of the interior of the positioner before activation, viewed from directly above.

[0026] Figure 5A It is a schematic diagram of the interior of the activation unit viewed horizontally.

[0027] Figure 5B This is a schematic diagram of the interior of the activation unit as viewed from directly above.

[0028] Figure 6A This is a horizontal view of the interior of the pre-contraction cleaning unit.

[0029] Figure 6B This is a schematic diagram of the interior of the pre-contraction cleaning unit viewed from directly above.

[0030] Figure 7A It is a schematic diagram of the interior of the coating unit viewed horizontally.

[0031] Figure 7B This is a schematic diagram of the interior of the coating unit viewed from directly above.

[0032] Figure 7C and Figure 7D This is a schematic diagram of the filling fluid nozzle.

[0033] Figure 8A It is a schematic diagram of the interior of the joint unit viewed horizontally.

[0034] Figure 8B It is a schematic diagram of the interior of the joint unit viewed horizontally.

[0035] Figure 9A It is a schematic diagram of the interior of the grinding unit viewed horizontally.

[0036] Figure 9B This is a schematic diagram of the interior of the grinding unit viewed from directly above.

[0037] Figure 10 This is a block diagram showing the electrical structure of the substrate bonding device.

[0038] Figure 11A This is a schematic cross-sectional view of the outer periphery of the substrate.

[0039] Figure 11B It is a schematic diagram of the interior of the coating unit viewed horizontally.

[0040] Figure 11C This is a schematic cross-sectional view showing the state of supplying filler liquid to the outer periphery of the bonding surface of the substrate.

[0041] Figure 11D It is a schematic cross-sectional view showing the state of voids in the filler on the substrate detected by a void detector.

[0042] Figure 11E This is a schematic cross-sectional view showing the state of the gap between the two substrates after bonding, as detected by a gap detector.

[0043] Figure 12 It is a schematic top view of the substrate showing the device area and non-device area. Detailed Implementation

[0044] Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings.

[0045] In the following description, "bonded substrate W" refers to two substrates W that have been bonded together; "pre-bonding substrate W" refers to the substrate W before bonding; and "post-bonding substrate W" refers to the substrate W after bonding. "Lamination" has the same meaning as "bonding".

[0046] 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 that have been bonded refer to the bonded substrate W. The two substrates W after bonding also refer to the bonded substrate W. When any of the bonded substrate W, the substrate W before bonding, and the substrate W after bonding can be used, it is simply referred to as substrate W.

[0047] Figure 1A This is a schematic diagram showing an example of the appearance of two substrates W before and after bonding. Figure 1B This is a schematic diagram showing an example of a cross-section of two substrates W before and after bonding. Figure 1C This is a schematic diagram showing an example of a cross-section of substrate W before and after the filling liquid FL is supplied to the bonding surface WA of substrate W. Figure 1D This is a schematic diagram showing an example of the cross-sections of two substrates W before and after thinning of two bonded substrates W.

[0048] like Figure 1A As shown, the first substrate W1 and the second substrate W2 are flat circular plates with the same diameter. The diameter of the first substrate W1 and the second substrate W2 can be 300 mm or other values. The thermal expansion coefficient of the first substrate W1 can be the same as or different from that of the second substrate W2. 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.

[0049] 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 front and back surfaces of substrate WD2 are also similar. The front surfaces of substrates WD1 and WD2 are device forming surfaces where transistors or other devices are formed. 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 substrates WD1 or WD2 can also be device forming surfaces.

[0050] When viewed perpendicular to the surface of substrate WD1, a V-shaped notch with an opening at the end face of substrate WD1 is formed on the outer periphery of substrate WD1. An orientation flat, not a notch, may also be formed on the outer periphery of substrate WD1. The notch and orientation flat indicate the crystal orientation of substrate WD1 or substrate WD2. First substrate W1 is positioned circumferentially with reference to the notch or orientation flat of first substrate W1. The same applies to second substrate W2.

[0051] 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 semi-transparent 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 also be silicon oxide films made using TEOS (tetraethoxysilane).

[0052] 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 ambient gas 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 ambient gas in the space in which the second substrate W2 is disposed.

[0053] Figure 2 This is a process diagram illustrating a substrate bonding method according to an embodiment of the present invention. When bonding 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), and a cleaning process is performed to clean and dry the two activated substrates W. Figure 2 Step S2). Subsequently, a coating process is performed to coat at least one of the first substrate W1 and the second substrate W2 with a filling liquid FL. Figure 2 Step S3). Figure 1C This is an example of applying filler liquid FL to the outer periphery of the bonding surface WA2 of the second substrate W2 before bonding with the first substrate W1.

[0054] After the filling liquid FL is applied, a reversal process is performed to reverse one of the first substrate W1 and the second substrate W2. Figure 2 Step S4). Then, the following process is performed: a positioning confirmation process to confirm the positioning of the relative positions and angles of the first substrate W1 and the second substrate W2 (…). Figure 2 Step S5), a positioning adjustment process that adjusts the positions of the first substrate W1 and the second substrate W2 according to the confirmed positioning. Figure 2 Step S6), and the substrate contact process of bringing the first substrate W1 and the second substrate W2, after positioning and adjustment, into contact to join the first substrate W1 and the second substrate W2. Figure 2 Step S7). Then, the following process is performed: an inspection process to check the bonding accuracy of the first substrate W1 and the second substrate W2, that is, the offset of the positions 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. Figure 2 Step S8).

[0055] The activation process can also be a plasma treatment that irradiates the bonding surfaces WA1 of the first substrate W1 and WA2 of the second substrate W2 with plasma such as oxygen plasma. In this case, moisture in the air or moisture supplied to the substrate W during the cleaning process comes into contact with the bonding surfaces WA1 of the first substrate W1 and WA2 of the second substrate W2, which are irradiated with plasma, and hydrophilic groups such as carboxyl groups (OH groups) are formed 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 also be a wet treatment that supplies a hydrophilic liquid that forms hydrophilic groups to the bonding surfaces WA1 of the first substrate W1 and WA2 of the second substrate W2.

[0056] The substrate contact process can be a process of directly bonding two substrates W in an atmosphere at room temperature (e.g., 20~30°C). The substrate contact process can also 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 step of bonding the two substrates W by pressing one of the two substrates W against the other without pressing one of the two substrates W against the other, or by pressing one of the two substrates W against the other with pressure that does not damage the devices formed on the two substrates W.

[0057] Figure 1B It represents a cross-section in which the first substrate W1 and the second substrate W2 are cut by 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 is an example of a hydrophilic group, specifically a carboxyl group 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 carboxyl group is bonded to the silicon atom (Si) in the bonding layers WB1 and WB2.

[0058] Before bonding, the bonding surfaces WA1 of the first substrate W1 and WA2 of the second substrate W2 are terminated with multiple carboxyl groups. 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 due to intermolecular forces acting between the two carboxyl groups. Depending on the situation, water molecules detach from the two carboxyl groups, and silicon atoms in the bonding layer WB1 of the first substrate W1 bond with silicon atoms in the bonding layer WB2 of the second substrate W2 via oxygen atoms. Thus, the first substrate W1 and the second substrate W2 are bonded.

[0059] After the first substrate W1 and the second substrate W2 are joined together, as follows Figure 1D The following grinding process is performed as shown. Figure 2 Step S9) and cleaning process ( Figure 2 In step S10), during the grinding process, one of the first substrate W1 and the second substrate W2 after bonding is ground, thereby thinning the first substrate W1 and the second substrate W2 after bonding, i.e., the bonding substrate W. In 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 cutting the first substrate W1. Alternatively, the thickness of the second substrate W2 can be reduced instead of the thickness of the first substrate W1.

[0060] Inspection process ( Figure 2 Step S8) can be performed in the grinding process ( Figure 2 The process can be performed after step S9), rather than before it, or it can be performed before or after the grinding process. In the latter case, the bonding accuracy before and after the grinding process can be compared. The pass / fail determination can also be based on whether the change in bonding accuracy exceeds a threshold. The pass / fail determination can also be used to calculate the pass / fail rate, or a pass chart showing the relationship between the substrate W after the pass / fail determination and the qualified substrate W can be created, to record or display at least one of the pass rate and the pass chart.

[0061] like Figure 1C and Figure 1DAs 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 in which the filler FS, equivalent to the solute, is dissolved in a solvent, or a liquid containing the filler FS (with a concentration of 100% or approximately 100%), or a liquid other than those mentioned above. When the filler solution FL is a solution containing the filler FS and a solvent, the solvent can also be a liquid containing a substance with a higher volatility than water, such as IPA (isopropanol). For example, the filler solution FL can also be an SOG (spin-on-glass) liquid containing a siloxane component equivalent to the solute and an alcohol equivalent to the solvent.

[0062] When the grinding process begins, the filler fluid FL in the annular groove WG formed between the outer periphery of the first substrate W1 and the outer periphery of the second substrate W2 changes into filler FS. If necessary, a process to generate or promote the change from filler fluid FL to filler FS can be performed before the grinding process. For example, when the filler fluid FL changes into filler FS due to evaporation, a portion of the filler fluid FL can be evaporated by at least one of heating the filler fluid FL and reducing the gas pressure. When the filler fluid FL changes into filler FS by hardening the filler fluid FL, the filler fluid FL can be hardened by at least one of heating the filler fluid FL and irradiating the filler fluid FL with light. The above processes can be performed during the supply of filler fluid FL, after the supply of filler fluid FL is stopped, or both.

[0063] Next, as described above, the substrate bonding apparatus 1 for bonding two substrates W will be explained.

[0064] Figure 3 This is a schematic top view of a substrate bonding apparatus 1 according to an embodiment of the present invention. Unless otherwise specified, the vertical, horizontal, and front-back directions in the following description refer to the vertical, horizontal, and front-back directions of the substrate bonding apparatus 1. The vertical direction is the vertical direction. The horizontal and front-back directions are two mutually orthogonal horizontal directions. The arrangement direction of the plurality of carriers CA held by the plurality of loading ports LP is the horizontal direction. Each carrier CA is held in the loading port LP with its opening facing rearward.

[0065] The substrate bonding apparatus 1 is a device for bonding two circular substrates W. The substrate bonding apparatus 1 includes: multiple loading ports LP, each holding a FOUP (Front-Opening Unified Pod) or similar carrier CA for holding multiple substrates W; multiple processing units 2 for processing the substrates W fed from the multiple loading ports LP; a transport system TS for transporting the substrates W between the multiple loading ports LP and the multiple processing units 2; and an outer wall 1a forming a sealed space for housing the multiple processing units 2 and the transport system TS. The substrate bonding apparatus 1 also includes a control device 3 for controlling the substrate bonding apparatus 1.

[0066] Figure 3 This example illustrates a configuration with three loading ports LP. The three loading ports LP include: a first loading port LP1, which holds a carrier CA for housing a first substrate W1; a second loading port LP2, which holds a carrier CA for housing a second substrate W2; and a third loading port LP3, which holds a carrier CA for housing the first substrate W1 and the second substrate W2 after they have been joined. The first loading port LP1 and the second loading port LP2 are inlets for holding the carrier CA of the substrates W to be joined in the substrate joining device 1. The third loading port LP3 is an outlet for holding the carrier CA of the two substrates W after they have been joined in the substrate joining device 1.

[0067] Multiple processing units 2 include a pre-activation positioner 10, an activation unit 20, a pre-bonding cleaning unit 30, a pre-bonding positioner, a coating unit 40, a bonding unit 50, a grinding unit 60, and a post-grinding cleaning unit 70. Figure 3 This is an example where two of each of the pre-activation positioner 10, activation unit 20, pre-bonding cleaning unit 30, pre-bonding positioner, and coating unit 40 are provided, and the pre-bonding positioner and coating unit 40 are integrated.

[0068] The pre-activation positioner 10 is a unit that positions the substrate W in the circumferential direction of the substrate W based on a notch or orientation plane. The pre-bonding positioner 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 contacting plasma with the surface or back of the substrate W. The pre-bonding cleaning unit 30 is a unit that supplies cleaning fluid to the substrate W to clean the substrate W.

[0069] The bonding unit 50 is a unit that brings two substrates W into contact to bond the two substrates W together. The coating unit 40 applies a coating to an annular groove WG (see reference) formed between the outer peripheries of the two bonded substrates W. Figure 1C The unit 60 is a unit that supplies filling fluid. The grinding unit 60 is a unit that grinds the two bonded substrates W to make them thinner. The post-grinding cleaning unit 70 is a unit that supplies cleaning fluid to the two substrates W that have been thinned by grinding to clean the two substrates W.

[0070] The transport system TS transports the substrate W from the first loading port LP1 and the second loading port LP2 to multiple processing units 2, and transports the substrate W from the multiple processing units 2 to a third loading port LP3. The transport system TS also transports the substrate W between the multiple processing units 2. The transport system TS can be equipped with... Figure 3 At least one transport robot TR that transports one or more substrates W in a horizontal posture along a transport path TP, indicated by a thick line.

[0071] The transport robot TR includes at least one hand TH that holds a substrate W in a horizontal posture. The transport robot TR holds the substrate W horizontally with the hand TH and moves along the transport path TP. Figure 3 This represents the following example: the transport path TP extends from 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.

[0072] The following describes several processing units 2. First, the pre-activation positioner 10 will be described.

[0073] Figure 4A This is a schematic diagram of the interior of the positioner 10 before activation, viewed horizontally. Figure 4B This is a schematic diagram of the interior of the pre-activated positioner 10 as viewed from directly above.

[0074] like Figure 4A and Figure 4B As shown, the pre-activation positioner 10 includes: a chamber 11 forming an internal space for the placement of the substrate W and an opening through which the substrate W enters and exits the internal space; and a chuck 14 horizontally holding the substrate W within the chamber 11. The chamber 11 includes: a partition 12 forming the internal space and the opening; and a door 13 that moves relative to the partition 12 to open and close the opening.

[0075] The pre-activation positioner 10 further includes: an electric motor 15 that rotates the chuck 14, thereby causing the substrate W to rotate about a vertical rotation center A1 passing through the central portion of the substrate W held by the chuck 14; an outer peripheral position sensor 16 that detects the contour shape of the substrate W, thereby specifying the orientation of the notch or orientation plane; and a control device 3 that, based on the detection value of the outer peripheral position sensor 16, causes the electric motor 15 to rotate the chuck 14, thereby bringing the substrate W to a stop at a position where the orientation of the notch or orientation plane is aligned with a reference direction.

[0076] The chuck 14 can be a mechanical chuck that holds the substrate W horizontally by pressing multiple 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 is an example representing the latter. In the latter case, the peripheral position sensor 16 can also detect the contour shape of the substrate W to specify the position of the center of the substrate W. In this case, the pre-positioner 10 may further include a centering actuator that moves the chuck 14 horizontally, thereby bringing the center of the substrate W closer to the rotation center A1 of the substrate W.

[0077] An actuator is a device that converts driving energy, manifested as 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 may be provided to convert the actuator's motion into linear or rotary motion. For example, when the actuator is an electric motor and the object moves linearly, a motion converter such as a ball screw and ball nut can convert the rotation of the electric motor into linear motion.

[0078] Next, the activation unit 20 will be explained.

[0079] 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.

[0080] like Figure 5A and Figure 5B As shown, the activation unit 20 includes: a chamber 21 forming an internal space for a substrate W and an opening through which the substrate W enters and exits the internal space; a lower electrode 24L horizontally supporting the substrate W within the chamber 21; an upper electrode 24u disposed 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 movable relative to the partition wall 22 to open and close the opening.

[0081] Although not shown, the gas valve 25V includes: a valve body having an annular valve seat through which gas passes; 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 can be a pneumatic actuator, an electric actuator, or an actuator other than those described above. Control device 3 (see reference) Figure 3 () controls the actuator to open and close the gas valve 25V.

[0082] Next, the pre-joining cleaning unit 30 will be described.

[0083] 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-contact cleaning unit 30 as viewed from directly above.

[0084] like Figure 6A and Figure 6B As shown, the pre-contact cleaning unit 30 includes: a chamber 31 forming an internal space for the substrate W and an opening through which the substrate W enters and exits the internal space; a chuck 34 horizontally holding the substrate W within the chamber 31; an electric motor 35 rotating the chuck 34, thereby causing the substrate W to rotate 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 dispensing cleaning liquid or other processing liquids toward the substrate W held by the chuck 34. The chamber 31 includes: a partition wall 32 forming the internal space and the opening; and a door 33 that moves relative to the partition wall 32 to open and close the opening. The cleaning liquid can be pure water (deionized water (DIW)) or a liquid other than pure water.

[0085] Although not labeled, the post-grinding cleaning unit 70 (see reference) Figure 3 The 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 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. In this respect, the pre-bonding cleaning unit 30 and the post-grinding cleaning unit 70 differ from each other.

[0086] Next, the coating unit 40 will be described.

[0087] 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.

[0088] The coating unit 40 includes a pre-joining positioner. The pre-joining positioner has components similar to the pre-activation positioner 10 (see reference 10). Figure 4A and Figure 4BThe coating unit 40 has the same structure as the pre-activation positioner 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 the structure of the pre-activation positioner 10 from 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.

[0089] The coating unit 40 includes at least one filling liquid nozzle 49 that dispenses filling liquid toward the substrate W held by the chuck 44. Figure 7B This example illustrates the presence of two filling nozzles 49. The two filling nozzles 49 are arranged at a distance from each other in the rotational direction Dr of the chuck 44. The two filling nozzles 49 dispense filling liquid toward two target positions separated by the rotational direction Dr of the chuck 44. Each target position is located within the outer periphery of the substrate W held by the chuck 44.

[0090] Figure 7A and Figure 7B This example illustrates a filling nozzle 49 positioned above the substrate W, dispensing filling liquid in a direction perpendicular to the upper surface of the substrate W. The direction in which the filling liquid is dispensed from the nozzle 49 can also be an angled direction relative to the upper surface of the substrate W, rather than a vertical direction. The dispensing direction can be angled inwards or outwards radially (orthogonal to the centerline of the substrate W), or upstream or downstream in the rotational direction Dr of the substrate W. The dispensing direction can also be angled in both the radial and rotational directions Dr of the substrate W.

[0091] 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 may also be a mist nozzle that ejects liquid in a mist-like manner, or an inkjet nozzle that forms multiple droplet columns, or other nozzles mentioned above. Figure 7C and Figure 7D This is an example of filling fluid nozzle 49 being an inkjet nozzle.

[0092] A mist nozzle can be a dual-fluid nozzle that produces mist by colliding liquid and gas, either an externally mixed or internally mixed type. It can also be a spray nozzle that discharges compressed liquid from the orifice or uses the Venturi effect to produce mist.

[0093] The inkjet nozzle can be a piezoelectric or thermal inkjet nozzle, or an inkjet nozzle other than piezoelectric or thermal. The inkjet nozzle can be a large-diameter nozzle 49X with a relatively large diameter ejection orifice 49x, or a small-diameter nozzle 49Y with a relatively small diameter ejection orifice 49y.

[0094] Figure 7C This is an example of a large-diameter nozzle, 49X. Figure 7D This is an example of a small-diameter nozzle 49Y. The diameter of the nozzle orifice 49x of the large-diameter nozzle 49X can be any of the following ranges, or outside of the ranges: 10 μm or less, 8 μm or less, and 3 μm or less. 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.

[0095] The filler nozzle 49 can be fixed to the partition wall 42 or can be movable relative to the partition wall 42. When multiple filler nozzles 49 are provided in a coating unit 40, at least one filler nozzle 49 can be fixed to the partition wall 42, while the remaining at least one filler nozzle 49 can be movable relative to the partition wall 42.

[0096] 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 also include a nozzle actuator 49a for operaling the filler nozzle 49 relative to the partition wall 42. The nozzle actuator 49a may be provided for each filler nozzle 49, or for each plurality of filler nozzles 49. Figure 7A and Figure 7B This is an example representing the former.

[0097] The nozzle actuator 49a may also include at least one of a horizontal actuator that moves the filling fluid nozzle 49 horizontally, a vertical actuator that moves the filling fluid nozzle 49 vertically, and a posture-changing actuator that changes the posture of the filling fluid nozzle 49. When the filling fluid nozzle 49 is moved 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.

[0098] like Figure 7A and Figure 7BAs 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 substrate W. The height sensor 47 can be a laser sensor or any other type of sensor.

[0099] 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, while 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, when the height sensor 47 measures the height of the substrate W, and the substrate W and the chuck 44 are rotated more than 360 degrees, the height of the substrate W is measured over its entire circumference.

[0100] By measuring the height of the upper surface of the substrate W over its entire circumference, the shape of the upper surface of the substrate W can be measured over its entire circumference. For example, if the height of the outer periphery of the upper surface of the substrate W is measured over its entire circumference, more specifically from the end face of the substrate W to a position further inward than that end face, the shape of the outer periphery of the upper surface of the substrate W, including the end face of the substrate W, can be measured. By measuring the shape of the outer periphery of the upper surface of the substrate W at each rotation angle around the rotation center A1 of the chuck 44, it is also possible to measure how the shape of the outer periphery of the upper surface of the substrate W changes according to the circumferential position of the substrate W.

[0101] 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, when the peripheral position sensor 46 detects the position of the outer periphery of the substrate W and the substrate W and the chuck 44 are rotated more than 360 degrees, the horizontal position of the outer periphery of the substrate W is detected throughout its entire circumference. This allows for the measurement of the shape of the outer periphery of the substrate W.

[0102] By measuring the shape of the outer periphery 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 measured. The orientation of the notch or orientation plane relative to the chuck 44 can also be measured. Furthermore, since the position of the outer periphery of the substrate W is measured for each rotation angle around the rotation center A1 of the chuck 44, it is also possible to measure how the horizontal position of the outer periphery of the substrate W changes according to the circumferential position of the substrate W.

[0103] The coating unit 40 includes a void detector 48, which captures images of voids within at least one of the filling liquid and filler on the substrate W held by the chuck 44. The void detector 48 can be an infrared camera or any other type of camera, as long as it can capture images of the voids within the filling liquid and filler. When 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) sensor.

[0104] When the gap detector 48 is an infrared camera, the coating unit 40 can also have a light source 48s (see reference). Figure 7A The light source 48s irradiates the outer periphery of the substrate W held by the chuck 44 with infrared light. The light source 48s can be located within the coating unit 40 or outside of it. In the latter case, the light from the light source 48s can be guided into the coating unit 40 by 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.

[0105] Figure 7B This example illustrates the provision of one void detector 48 for each filling fluid nozzle 49. Therefore, in this example, two void detectors 48 are provided. However, this is not a limitation; one void detector 48 may also be provided for every plurality of 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 within a range of less than 45 degrees with respect to the angle about the rotation center A1 of the chuck 44.

[0106] When the void detector 48 captures images of the filling liquid and filler on the substrate W held by the chuck 44, and the substrate W and the chuck 44 are rotated more than 360 degrees, images of the filling liquid, etc., are captured throughout the entire circumference of the substrate W. This allows for the inspection of the presence or absence of voids in the filling liquid or filler throughout the entire circumference of the substrate W. Furthermore, the void detector 48 can observe how the shape and position of the filling liquid or filler on the substrate W change according to the circumferential direction (the direction around the center line of the substrate W).

[0107] 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.

[0108] Figure 8A and Figure 8B This is a schematic diagram of the interior of the joining 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.

[0109] like Figure 8A and Figure 8B As shown, the bonding unit 50 includes: a chamber 51 having an opening through which the first substrate W1 and the second substrate W2 pass before and after bonding, and an internal space for the first substrate W1 and the second substrate W2 after being disposed through the opening; a first chuck 54A that horizontally holds the first substrate W1 within the chamber 51; and a second chuck 54B that horizontally holds the second substrate W2 within the chamber 51. The chamber 51 includes: a partition wall 52 that forms the internal space and the opening; and a door 53 that moves relative to the partition wall 52 to open and close the opening.

[0110] The bonding unit 50 further includes: a plurality of bonding actuators 55, which, when the first chuck 54A and the second chuck 54B are holding the first substrate W1 and the second substrate W2, move the first chuck 54A and the second chuck 54B relative to each other to bond the first substrate W1 and the second substrate W2; and at least one camera 56, which captures an image of at least one of the first substrate W1 and the second substrate W2, thereby detecting the positioning of the first substrate W1 and the second substrate W2 before and after bonding the first substrate W1 and the second substrate W2.

[0111] The plurality of engagement actuators 55 may also 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.

[0112] The multiple engagement actuators 55 may also include a reversing actuator that rotates the first chuck 54A about a horizontal linear axis, thereby reversing the vertical orientation of the first substrate W1 held by the first chuck 54A. The reversing actuator may also reverse the vertical orientation of the first substrate W1 held by a chuck other than the first chuck 54A. The reversing actuator may also reverse the vertical orientation of the first substrate W1 outside the engagement unit 50. When the hand TH of the transport robot TR (see reference) Figure 3 In cases where the first substrate W1 can be held horizontally downwards (in cases where the hand TH is a vacuum hand or a Bernoulli hand, etc.), the reverse actuator can also be part of the transport robot TR.

[0113] At least one camera 56 may also include: a first camera 56A, which captures images of the first substrate W1 before it is joined with the second substrate W2; a second camera 56B, which captures images of the second substrate W2 before it is joined with the first substrate W1; and a third camera 56C, which captures images of the first substrate W1 and the second substrate W2 after they are joined. The first camera 56A may capture images of the first substrate W1 held by the first chuck 54A, or it may capture images of 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 capture images of the joined substrate 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 capture images of the joined substrate W held by a chuck other than the first chuck 54A and the second chuck 54B. At least one camera 56 may also capture images of at least one of the first substrate W1 and the second substrate W2 outside the joining unit 50.

[0114] The first camera 56A and the second camera 56B are positioning cameras used to confirm and adjust the positioning of the first substrate W1 and the second substrate W2 before bonding. The third camera 56C is an inspection camera used to confirm the positioning of the first substrate W1 and the second substrate W2 after bonding. The inspection camera is an infrared camera that converts infrared light into electrical signals to generate electronic data such as still images or moving images. The positioning camera can be an infrared camera or a visible light camera that converts visible light into electrical signals to generate electronic data such as still images or moving images.

[0115] Next, the grinding unit 60 will be described.

[0116] 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.

[0117] like Figure 9A and Figure 9BAs shown, the grinding unit 60 includes: a chamber 61 forming an opening through which the bonding substrates W, i.e., the first substrate W1 and the second substrate W2 after bonding, pass, and an internal space for the bonding substrates W after being disposed through the opening; a chuck 64 horizontally holding the bonding substrates W within the chamber 61; and an electric motor 65 that rotates the chuck 64, thereby causing the bonding substrates W to rotate about a vertical rotation center A1 passing through the central portion of the bonding substrates W held by the chuck 64. The chamber 61 includes: a partition wall 62 forming the internal space and the opening; and a door 63 that moves relative to the partition wall 62 to open and close the opening.

[0118] 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, wheel-shaped member 67 holding the grinding stone 66; an electric motor 68 that rotates the grinding stone 66 and the wheel-shaped member 67 about a vertical center of rotation passing through the central portion of the wheel-shaped member 67; and a lifting actuator 69 that moves the grinding stone 66 and the wheel-shaped member 67 vertically. When the chuck 64 and the wheel 67 are rotated, and the grinding stone 66 contacts the upper surface of the bonding substrate W, the grinding stone 66 cuts the entire area of ​​the upper surface of the bonding substrate W.

[0119] Next, the electrical structure of the substrate bonding device 1 will be explained.

[0120] 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.

[0121] 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 storage device 3e that stores information such as a program P that needs to be sent and received between the computer body 3a 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 a host HC. Both the memory 3c and the storage device 3e are examples of storage devices that store information that needs to be sent and received between the computer body 3a and the CPU 3b.

[0122] The control device 3 is connected to the input device 3h and the display device 3i. When a user or maintenance supervisor needs to input information into the substrate bonding apparatus 1, the input device 3h is activated. The information is displayed on the screen of the display device 3i. The input device 3h can be any of the following: a keyboard, an indicator device, or a touch panel, or a device other than those mentioned above. Alternatively, a touch panel display that combines the functions of the input device 3h and the display device 3i can be provided on the substrate bonding apparatus 1.

[0123] CPU 3b executes program P stored in storage device 3e. Program P in storage device 3e can be pre-installed in control device 3, or it can be sent to storage device 3e from removable medium RM via reader 3f, or it can be sent to storage device 3e from external device such as host HC via communication device 3g.

[0124] Memory 3c is a volatile memory that retains its storage only when power is supplied. Storage device 3e and removable medium RM are non-volatile memories that retain their storage even when power is not supplied. Storage device 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 an optical disc 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.

[0125] Storage device 3e stores multiple recipes RC. Each recipe RC specifies the processing content, processing conditions, and processing procedure for substrate W. The multiple recipes RC 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 recipe RC specified by host HC. Control device 3 is programmed to execute the processes described later.

[0126] The formulation RC includes the coating amount (the total amount of filler liquid supplied to a substrate W before bonding), the coating start position (the position where the filler liquid supply to the substrate W begins), and the coating end position (the position where the filler liquid supply to the substrate W ends). In other words, the formulation RC specifies the coating amount, etc. The path traversed by the filler liquid nozzle 49 when it is moved is also included in the formulation RC. The user can edit the formulation RC to change the coating amount, etc. The formulation RC can be edited by the user operating the input device 3h, or by the user operating a device other than the substrate bonding apparatus 1, such as a personal computer. In the latter case, the edited formulation RC can be sent to the control device 3 via the communication device 3g.

[0127] Next, the coating of the filling liquid onto the substrate W will be explained. First, the shape of the substrate W will be explained, and then the coating of the filling liquid onto the substrate W will be explained.

[0128] Figure 11A This is a schematic cross-sectional view of the outer periphery of substrate W. Figure 11B This is a schematic diagram of the interior of the coating unit 40 viewed horizontally. Figure 11C This is a schematic cross-sectional view showing the state of supplying filling liquid FL to the outer periphery O1 of the bonding surface WA of the substrate W. Figure 11D This is a schematic cross-sectional view showing the state of voids V1 in the filler FS on the substrate W detected by void detector 48. Figure 11E 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 gap detector 48.

[0129] The outer periphery of the substrate W is also called the beveled edge. Figure 11A This is an example where 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 may also be a shape other than semi-circular or parabolic, such as a trapezoid. Hereinafter, the state where the surface and back surface of the substrate W are horizontal will be described.

[0130] The outer surface of substrate W includes a mating surface WA that contacts other substrates W, a non-matting 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 mating surface WA to the outer periphery of the non-matting surface WN. The end face of substrate W is a region encompassing a predetermined range of the front end WE of substrate W.

[0131] The bonding surface WA of substrate W includes: a circular flat portion F1, which is horizontal and flat; and an annular outer peripheral portion O1, which extends from the outer periphery of the flat portion F1 to 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 circular flat portion F2, which is horizontal and flat; and an annular outer peripheral portion O2, which extends from the outer periphery of the flat portion F2 to the front end WE in a manner that increases as it approaches the front end WE.

[0132] The flat portion F1 of the bonding surface WA corresponds to the device formation area where the device is formed. 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 at the center line of the substrate W. The center of the flat portion F2 of the non-bonding surface WN is also the same. When the cross-section of the outer periphery of the substrate W is semi-circular or parabolic, the cross-sections of the outer periphery O1 and outer periphery O2 are arc-shaped. When the cross-section of the outer periphery of the substrate W is trapezoidal, the cross-sections of the outer periphery O1 and outer periphery O2 are straight.

[0133] When Figure 11A When two substrates W are bonded together as shown, annular grooves WG with openings at the end faces of the two substrates W are formed on the outer periphery of the bonded substrates W. The annular grooves WG are formed between the two substrates W from their outer periphery. The annular grooves WG are continuous throughout 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 grooves 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 grooves WG. The depth of the annular grooves WG increases continuously or intermittently near the center of the annular grooves WG in the width direction.

[0134] As described above, after bonding the two substrates W, a grinding stone 66 (see reference) is used. Figure 9A After thinning and bonding, substrate W is one of the two substrates W after lamination. 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 laminated substrates W separate from each other, forming a gap equivalent to the annular groove WG. When in the filler FS (refer to...) Figure 1D When grinding the bonded substrate W in a state where the annular groove WG is not present, a force is applied to the outer periphery of the substrate W from the grinding stone 66, 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 filling liquid FL, which is changed to a solid or semi-solid filler FS, to the annular groove WG.

[0135] However, if the filling liquid FL is supplied to the annular groove WG after the two substrates W are bonded together, there is a situation where the filling liquid FL has difficulty reaching the bottom of the annular groove WG. Figure 11A This is an example of a cross-section of the substrate W where this phenomenon occurs.

[0136] exist Figure 11A In the example shown, the outer periphery O1 of the bonding surface WA of the substrate W forms the step Wb, which corresponds to the step forming portion forming the annular step Wb on the bonding surface WA. The outer periphery O1 of the bonding surface WA is a continuous annulus concentric with the flat portion F1 of the bonding surface WA and extends continuously throughout the circumference of the substrate W. The outer periphery O1 of the bonding surface WA is recessed from the flat portion F1 of the bonding surface WA toward the non-bonding surface WN. The height of the step Wb is less than 1 / 4 of the thickness of the substrate W. The height of the step Wb is, for example, in the range of 0.1 μm to 1.0 μm.

[0137] Figure 11AThe black dot indicates the position of the outer periphery (outer edge) of the flat portion F2 of the non-bonded surface WN. The outer periphery (outer edge) of the flat portion F1 of the bonded surface WA is positioned further inward than the outer periphery (outer edge) of the flat portion F2 of the non-bonded surface WN. Therefore, the diameter of the flat portion F1 of the bonded surface WA is smaller than the diameter of the flat portion F2 of the non-bonded surface WN. The outer periphery of the flat portion F1 of the bonded surface WA can be positioned further inward than that of the other substrates W (in... Figure 11A The position of the flat portion of the bonding surface of the first substrate W1) is located more inward than the outer periphery, or it can be located more outward than the outer periphery.

[0138] When having such Figure 11A When two substrates W with the step Wb shown are bonded together, or when a substrate W with the step Wb is bonded to a substrate W without the step Wb, a narrow gap is formed between the two substrates W. This gap forms the bottom of the annular groove WG. Even if a filling liquid is supplied to the annular groove WG with such a gap, the filling liquid is difficult to reach the bottom of the annular groove WG. Therefore, not after bonding the two substrates W, but before bonding, the filling liquid is applied to the bonding surface WA of one or both of the two substrates W.

[0139] When the filler liquid FL is applied to the outer periphery O1 of the bonding surface WA of the substrate W before bonding, as follows: Figure 11B As shown, the conveyor robot TR (refer to...) Figure 3 The substrate W is moved into the coating unit 40 and held horizontally by the chuck 44. Thus, the substrate W is held horizontally with the mating surface WA, i.e., the surface of the substrate W, facing upwards. In this state, the substrate W is rotated by the chuck 44, and the filling liquid FL is dispensed from the filling liquid nozzle 49 toward the outer periphery O1 of the mating surface WA of the substrate W.

[0140] The filler liquid FL ejected from the filler liquid nozzle 49 is applied to the outer periphery of the upper surface of the substrate W. The outer periphery of the upper surface of the substrate W corresponds to an example of the step-forming portion, namely the outer periphery O1 of the bonding surface WA. Figure 11C This is an example of filling nozzle 49 being an inkjet nozzle. In this example, multiple droplets of filling liquid FL ejected from filling nozzle 49 are directed toward the outer periphery of the upper surface of substrate W and disperse in approximately the same direction. These droplets collide with the outer periphery of the upper surface of substrate W. As a result, filling liquid FL is coated onto the outer periphery of the upper surface of substrate W.

[0141] Droplets of filler liquid FL coated on the outer periphery of the upper surface of substrate W remain at or near the point of collision with substrate W due to the viscosity of filler liquid FL and the force exerted on filler liquid FL from substrate W. Subsequent droplets of filler liquid FL collide with at least one of the upper surface of substrate W and the filler liquid FL adhering to the upper surface of substrate W, remaining at or near the point of collision. As a result, filler liquid FL accumulates on the outer periphery of the upper surface of substrate W.

[0142] The filler liquid FL on the substrate W remains in contact with the substrate W and changes into filler FS. As long as the filler liquid FL changes into filler FS when the grinding process to bond the substrate W begins, the filler liquid FL can change into filler FS during the dispensing of filler liquid FL from the filler liquid nozzle 49, or it can change into filler FS after the dispensing of filler liquid FL from the filler liquid nozzle 49 stops. In either case, a process that causes or promotes the change from filler liquid FL to filler FS can be performed.

[0143] The filler nozzle 49 ejects filler liquid FL towards the annular step Wb formed by the outer periphery of the upper surface of the substrate W, i.e., towards the inner periphery of the outer periphery O1 of the bonding surface WA, which coincides with the outer periphery of the flat portion F1 of the bonding surface WA. When the filler nozzle 49 is a droplet nozzle such as an inkjet nozzle, the control device 3 causes the nozzle actuator 49a to move the filler nozzle 49 radially toward the substrate W and spray droplets of filler liquid FL from the filler nozzle 49, thereby preventing the filler liquid FL from colliding with the upper surface of the substrate W at a position closer to the step Wb. As a result, the filler liquid FL accumulates on the outer periphery of the upper surface of the substrate W, thereby eliminating or reducing the size of the step Wb.

[0144] The range of the coating filler liquid FL can be the entire range from the step Wb on the upper surface of the substrate W to the front end WE of the substrate W, or it can be a part of that range. Figure 11C This is an example representing the latter. In the latter case, the filler liquid FL can be applied to at least a portion of a range that is further outward than the outer periphery of the flat portion F1 of the bonding surface WA and further inward than the outer periphery of the flat portion F2 of the non-bonding surface WN. As long as the step Wb is eliminated or reduced and has no effect when the two substrates W are bonded, the thickness of the filler liquid FL on the substrate W can be uniform or varied depending on the position of at least one of the circumferential and radial directions of the substrate W. Figure 11D This is an example representing the latter. The thickness of the filler FS is equal to or approximately equal to the thickness of the filler fluid FL.

[0145] If the radial distance from the rotation center A1 of the substrate W is the same, the thickness of the filler fluid FL on the substrate W is constant or approximately constant. Near the step Wb, regardless of the radial position of the substrate W, the thickness of the filler fluid FL is constant or approximately constant. The thickness of the filler fluid FL on the substrate W increases and then decreases as it approaches the front end WE of the substrate W. Near the step Wb, the thickness of the filler fluid FL on the substrate W is equal to or approximately equal to the height of the step Wb, or smaller than the height of the step Wb. Therefore, when two substrates W are bonded, excess filler fluid FL can be prevented from moving towards the bonding surface WA of the two substrates W.

[0146] The radial distance WE from the rotation center A1 of the substrate W to the front end of the substrate W can vary depending on the angle around the rotation center A1 of the substrate W. The height of the outer periphery of the substrate W can also vary depending on the angle around the rotation center A1 of the substrate W. Therefore, the position of the outer periphery of the upper surface of the substrate W can vary in at least one of the radial and vertical directions depending on the angle around the rotation center A1 of the substrate W.

[0147] The control device 3 can also move the filling liquid nozzle 49 by the nozzle actuator 49a according to the change in position of the outer periphery of the upper surface of the substrate W in at least one of the radial and vertical directions, thereby reducing the change in distance from the filling liquid nozzle 49 to the outer periphery of the upper surface of the substrate W. In this case, the filling liquid FL can be sprayed towards the rotating substrate W by the filling liquid nozzle 49 after measuring the change in position of the outer periphery of the upper surface of the substrate W throughout the entire circumference of the substrate W, or the filling liquid FL can be sprayed towards the rotating substrate W by measuring the change in position of the outer periphery of the upper surface of the substrate W.

[0148] Figure 11B The peripheral position sensor 46, height sensor 47, and gap detector 48 shown are examples of position detectors for detecting the position of the peripheral portion of the substrate W. Changes in the position of the peripheral portion of the upper surface of the substrate W can be detected by any one of the peripheral position sensor 46, height sensor 47, and gap detector 48, or by two or more of them. The height sensor 47 detects a certain range of height in the radial direction, thus enabling it to detect the shape and changes of the peripheral portion of the upper surface of the substrate W.

[0149] Figure 11B This example illustrates how a void detector 48 measures the position and shape changes of the outer periphery of the upper surface of a substrate W, and how a filling liquid nozzle 49 sprays filling liquid FL towards the rotating substrate W. In this example, the void detector 48 is positioned upstream of the filling liquid nozzle 49 in the rotation direction of the substrate W (see reference). Figure 7BSince the difference in rotation angle (angle difference around the rotation center A1 of the substrate W) between the gap detector 48 and the filling liquid nozzle 49 is known, and the rotation speed of the substrate W is known, the filling liquid nozzle 49 can be moved relative to the substrate W simply by using these values ​​and the amount and direction of change of the position of the outer periphery of the upper surface of the substrate W.

[0150] Not only the position of the outer periphery of the upper surface of the substrate W, but also the shape of the outer periphery of the upper surface of the substrate W can change according to the angle around the rotation center A1 of the substrate W. When the change in the shape of the outer periphery of the upper surface of the substrate W is measured by at least one of the height sensor 47 and the gap detector 48, the flow rate of the filler liquid FL ejected from the filler liquid nozzle 49 (the amount of filler liquid FL ejected from the filler liquid nozzle 49 per unit time) can be varied according to this change. In this way, the deviation of the surface height of the filler liquid FL at multiple positions on a circle concentric with the substrate W can be reduced. Regardless of whether the change in the shape of the outer periphery of the upper surface of the substrate W is measured, the control device 3 can vary the flow rate of the filler liquid FL.

[0151] When multiple substrates W are coated with filler liquid FL, the position of the outer periphery of the upper surface of the substrates W sometimes varies uniformly among the substrates W. Therefore, the control device 3 can move the filler liquid nozzle 49 by the nozzle actuator 49a according to the change in the position of the outer periphery of the upper surface of the other substrates W, thereby reducing the variation in the distance from the filler liquid nozzle 49 to the outer periphery of the upper surface of the substrate W. That is, as... Figure 11C As shown, the control device 3 can store measurement data D1 when measuring the position change of the outer periphery of the upper surface of other substrates W, and move the filling liquid nozzle 49 by the nozzle actuator 49a according to the measurement data D1. Not limited to this, it can be that whenever the substrate W of the chuck 44 changes, the control device 3 causes the gap detector 48 or the like to measure the position change of the outer periphery of the upper surface of the substrate W.

[0152] After applying a filler liquid FL to the outer periphery of the upper surface of substrate W, substrate W is bonded to other substrate W. When a step Wb is formed not only on the outer periphery O1 of the bonding surface WA of one substrate W but also on the outer periphery O1 of the bonding surface WA of the other substrate W, the two substrates W can be bonded after applying the filler liquid FL to the outer periphery O1 of the bonding surface WA of the other substrate W, or the two substrates W can be bonded without applying the filler liquid FL to the outer periphery O1 of the bonding surface WA of the other substrate W. In either case, the filler liquid FL or filler FS is disposed between the outer peripheries of the two substrates W, thus reducing the space within the annular groove WG formed between the outer peripheries of the two substrates W.

[0153] Thus, the filler FL is applied to the outer periphery O1 of the bonding surface WA of the substrate W in a manner that prevents the filler from adhering to the flat portion F1 of the bonding surface WA of the substrate W. Figure 11D As shown, after the supply of filling liquid FL is stopped, the interior of the filler FS on the substrate W can be observed by the void detector 48 to detect whether there is any coating defect. Figure 11D This represents an example of detecting voids V1 within the filler FS using void detector 48.

[0154] After the two substrates W are bonded together, the chuck 44 can hold the substrates W in place. For example... Figure 11E As shown, the gap detector 48 can detect the gap V1 in the filling liquid FL or filler FS within the annular groove WG of the bonding substrate W held by the chuck 44. The gap detector 48 can also detect the gap V2 between the bonding surfaces WA of the two bonded substrates W. When detecting gap V2, the gap detector 48 can be moved above or below the bonding substrate W held by the chuck 44, or other gap detectors 48 can be positioned above or below the bonding substrate W held by the chuck 44. The third camera 56C of the bonding unit 50 (see reference...) Figure 8A It can also detect the gaps V1 and V2 of the bonding substrate W held by the second chuck 54B.

[0155] After applying a filler liquid only to the outer periphery O1 of the bonding surface WA of substrate W and bonding two substrates W together, the bonding substrate W is ground. When grinding of the bonding substrate W begins, the filler liquid FL in the annular groove WG changes to filler FS. When the bonded substrate W, i.e., one of the two bonded substrates W, is cut using a grinding stone 66, the outer periphery of the bonded substrate W is supported by the filler FS. Therefore, the generation of debris and associated particles at the end notches of the thinned substrate W can be prevented or reduced. As a result, particles adhering to the device can be reduced, thus improving the device yield.

[0156] Next, the effects of this implementation method will be explained.

[0157] In this embodiment, instead of supplying the filler liquid after bonding the two substrates W, the filler liquid is supplied only to the outer periphery O1 of the bonding surface WA of the substrates W before bonding the two substrates W. Then, the two substrates W coated with the filler liquid are bonded, or the substrate W coated with the filler liquid is bonded to a substrate W without the filler liquid. Therefore, compared to the case where the filler liquid is supplied to the annular groove WG formed between the outer peripheries of the two substrates W after bonding the two substrates W, the filler liquid can be disposed at a deeper position within the annular groove WG.

[0158] In this embodiment, the outer periphery O1 of the bonding surface WA of the substrate W is recessed from the outer periphery of the flat portion F1 of the bonding surface WA of the substrate W, forming a step Wb. When the bonding surface WA of the substrate W has such a step Wb, a narrow gap is formed between the two substrates W when the substrate W is bonded to another substrate W. This gap corresponds to the bottom of the annular groove WG. With such a gap, even if filling liquid is supplied after the two substrates W are bonded, the filling liquid is difficult to reach the bottom of the annular groove WG. The filling liquid nozzle 49 supplies filling liquid only to the outer periphery O1 of the bonding surface WA of the substrate W before the two substrates W are bonded. Therefore, even when the bottom of the annular groove WG is narrow, the filling liquid can be positioned at the bottom of the annular groove WG.

[0159] In this embodiment, multiple droplets of filler liquid are sprayed onto the outer periphery O1 of the bonding surface WA of the substrate W held by the chuck 44. This allows for precise control of the amount of filler liquid supplied to the outer periphery O1 of the bonding surface WA of the substrate W, compared to the case of continuous filler liquid dispensing. When the outer periphery O1 of the bonding surface WA of the substrate W has a step Wb that is recessed from the outer periphery of the flat portion F1 of the bonding surface WA of the substrate W, when a large amount of filler liquid is supplied to the outer periphery O1 of the bonding surface WA of the substrate W, some excess filler liquid may move to the flat portion F1 of the bonding surface WA of the substrate W. By precisely controlling the amount of filler liquid, such excess filler liquid can be eliminated or reduced.

[0160] In this embodiment, the position of the outer periphery of the substrate W held by the chuck 44 is detected, and the filling liquid nozzle 49 is moved by the nozzle actuator 49a according to the detected position. As a result, the filling liquid nozzle 49 moves in at least one of the horizontal and vertical directions along with the change in the position of the outer periphery of the substrate W, thus reducing the change in distance from the filling liquid nozzle 49 to the substrate W caused by the rotation of the substrate W. Therefore, the position of the supplied filling liquid can be controlled with good precision. When the amount of filling liquid FL ejected from the filling liquid nozzle 49 per unit time varies according to the detected position, the deviation in the surface height of the filling liquid FL at multiple positions on a circle concentric with the substrate W can be reduced.

[0161] In this embodiment, the peripheral position sensor 46, the height sensor 47, and the gap detector 48 are equivalent to position detectors. The control device 3 stores measurement data D1 (refer to) when the position detector detects the position of the peripheral portion of other substrates W. Figure 11CThe control device 3 moves the filling liquid nozzle 49 by the nozzle actuator 49a based on the measurement data D1. When applying filling liquid to multiple substrates W, the position of the outer periphery of the substrate W may vary similarly among the substrates W. In such cases, by using the measurement data D1 of other substrates W, compared to detecting the position of the outer periphery of the substrate W each time, the time to complete the filling liquid supply can be shortened, and the variation in distance from the filling liquid nozzle 49 to the substrate W can be reduced.

[0162] In this embodiment, a coating unit 40 is provided in the substrate bonding apparatus 1 that joins two substrates W. The coating unit 40, as described above, supplies filler liquid only to the outer periphery O1 of the bonding surface WA of the substrates W. Therefore, not only can the time from applying filler liquid to one or both of the two substrates W to joining the two substrates W be shortened, but the filler liquid can also be positioned deeper within the annular groove WG.

[0163] In this embodiment, in addition to the bonding unit 50 and the coating unit 40, the substrate bonding apparatus 1 also includes a grinding unit 60 for grinding the bonded substrates W after the filler liquid has been applied. Therefore, the time from bonding the two substrates W to grinding the bonded substrates W can be shortened. The filler liquid applied to the bonded substrates W changes to a solid or semi-solid filler. Therefore, it is possible to suppress the deflection of the outer periphery of the substrates W due to the force applied from the grinding stone 66, and to grind the bonded substrates W.

[0164] Next, other implementation methods will be described.

[0165] Alternatively, the filling liquid can be applied only to a portion of the circumferential region of the substrate W, instead of coating the entire circumference of the substrate W. Figure 12 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 in the circumferential direction of the substrate W.

[0166] 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 12 In the diagram, the outer edge of the device region is represented by a thick line. The device region is the area where devices and patterns such as transistors are present. The non-device region is the area where devices and patterns are not present. The non-device region is the ring-shaped area surrounding the device region.

[0167] 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. When this shortest distance is relatively short, it is easier to grind the bonding substrate W from the grinding stone 66 (see reference). Figure 9AA relatively large force is applied to the device located at the end of the device region. If a crack or gap is generated on the outer periphery of the bonding substrate W during grinding and reaches the device located at the end of the device region, that device (containing the crack, etc.) becomes defective. The shorter this minimum distance, the more likely the device defect will occur. Figure 12 As shown, the filler liquid can be applied only to several areas (enclosed by double-dotted lines) with relatively shortest distances. This prevents the application of large forces to devices located at the ends of the device region and reduces the time required for filler liquid application compared to applying filler liquid to the entire circumference of the substrate W.

[0168] The filling liquid nozzle 49 can continuously eject 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 eject 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, it may also be provided that: a droplet nozzle sprays multiple droplets of filling liquid toward the substrate W; and a liquid column nozzle continuously ejects filling liquid in a manner that forms a continuous liquid column from the filling liquid nozzle 49 to the substrate W.

[0169] If, after spraying multiple droplets of filler liquid toward the substrate W, the filler liquid is continuously ejected in a manner that forms a continuous liquid column from the filler liquid nozzle 49 to the substrate W, the initial position of the filler liquid supply can be precisely controlled, and then the filler liquid can be supplied at a high speed. Therefore, compared to the case where multiple droplets of filler liquid are sprayed from the beginning to the end, the time for completing the supply of filler liquid can be shortened.

[0170] 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 case, droplets of filler liquid ejected from the nozzle 49y of the small-diameter nozzle 49Y can be supplied to the outer periphery O1 of the bonding surface WA of the substrate W. Subsequently, droplets of filler liquid ejected from the nozzle 49x of the large-diameter nozzle 49X can be supplied to the outer periphery O1 of the bonding surface WA of the substrate W. This makes it difficult for voids to form at the interface between the filler liquid and the substrate W, and shortens the time required for filler liquid coating.

[0171] 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 also be a device different from the substrate bonding apparatus 1, located outside the outer wall 1a of the substrate bonding apparatus 1.

[0172] 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.

[0173] Two or more of the above structures can also be combined. Alternatively, two or more of the above-described processes can be combined.

[0174] Although the embodiments of the present invention have been described in detail, the above description is merely a series of specific examples used to make the technical content of the present invention clearer. The present invention is not to be construed as limited to these specific examples, and the spirit and scope of the present invention are defined only by the appended claims.

[0175] This invention claims priority based on Japanese Patent Application No. 2023-188939, 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 a substrate having a mating surface that engages with other substrates, and rotates about an axis orthogonal to the main surface of the substrate and passing through the center of the main surface; and The filling nozzle ejects filling liquid, which is transformed into a solid or semi-solid form, toward the mating surface of the substrate held by the chuck, thereby supplying the filling liquid only to the outer periphery of the mating surface of the substrate.

2. The coating unit according to claim 1, characterized in that, The aforementioned bonding surface of the substrate includes: a flat portion that bonds to other substrates; and an outer peripheral portion that is recessed from the outer periphery of the flat portion toward the non-bonding surface of the substrate opposite to the bonding surface.

3. The coating unit according to claim 1 or 2, characterized in that, The aforementioned filling fluid nozzle is a droplet nozzle that sprays multiple droplets of the filling fluid toward the outer periphery of the bonding surface of the substrate held by the chuck, thereby supplying the filling fluid only to the outer periphery of the bonding surface of the substrate.

4. The coating unit according to claim 3, characterized in that, The aforementioned droplet nozzle includes: a large-diameter nozzle that sprays a plurality of droplets of the filling liquid from a spray port toward the outer periphery of the mating surface of the substrate held by the chuck; and a small-diameter nozzle that sprays a plurality of droplets of the filling liquid from a spray port with an area smaller than the spray port of the large-diameter nozzle toward the outer periphery of the mating surface of the substrate held by the chuck.

5. The coating unit according to any one of claims 1 to 4, characterized in that, Also includes: A position detector detects the position of the outer periphery of the substrate held by the chuck; and A nozzle actuator that moves the filling fluid nozzle based on the position of the outer periphery detected by the position detector.

6. The coating unit according to claim 5, characterized in that, It also includes a control device that performs at least one of the following controls based on the position of the outer periphery of the other substrate detected by the position detector: position control, which moves the filling liquid nozzle by the nozzle actuator; and flow control, which detects the position of the outer periphery of the substrate held by the chuck by the position detector and changes the amount of filling liquid ejected from the filling liquid nozzle per unit time based on the position of the outer periphery detected by the position detector.

7. A substrate bonding apparatus, characterized in that, It comprises: a coating unit that coats a filler liquid, which transforms into a solid or semi-solid state, onto a substrate; and a bonding unit that bonds two substrates after at least one of them has been coated with the aforementioned filler liquid. The above coating unit includes: A chuck that holds a substrate having a mating surface that engages with other substrates, and rotates about an axis orthogonal to the main surface of the substrate and centered on the center of the main surface; and A filling nozzle dispenses the filling liquid toward the mating surface of the substrate held by the chuck, thereby supplying the filling liquid only to the outer periphery of the mating surface of the substrate.

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