Apparatus and method for joining substrates together

Abstract

The present invention relates to an apparatus for bonding a first substrate to a second substrate, the apparatus comprising at least one deformation device for deforming at least one of the substrates by a fluid, the at least one deformation device being movable. The present invention also relates to a corresponding method.

Description

Technical Field

[0001] The present invention relates to an apparatus and a method for bonding substrates as recited in the independent claims.

[0002] In the semiconductor industry, there are multiple methods for aligning and bonding (joining) two, particularly structured substrates to each other. A fusion bond or fusion bonder means an apparatus that generates the joining of two substrates by using an actuator, particularly pins, and contacting them particularly at the center. In this case, self-fixation due to the adhesion force between the substrate surfaces occurs.

[0003] If the fixation is time-limited or the fusion bond has not yet been subjected to heat treatment, pre-bonding is mentioned. Pre-bonding can also be interpreted broadly as a temporary bond. This is because pre-bonding is reversible, that is, the substrates can be separated from each other again without damage. Hereinafter, the words bonding, temporary bonding, and pre-bonding are used synonymously.

[0004] In the prior art, the following methods or apparatuses are known.

[0005] European Patent No. 3005407 discloses a mechanically movable pin. However, it is disadvantageous that this pin applies force not only perpendicular to the substrate surface but also parallel to the substrate surface to the substrate.

[0006] In International Publication No. 2013 / 023708, a stationary nozzle that does not allow major control means is used. European Patent No. 2351076 discloses a pressurized gas flow through a passage. However, also in this specification, the main means of control is not provided, which results in significant drawbacks in bonding accuracy.

[0007] One of the biggest technical challenges when joining two substrates is the accuracy of the functional units between them. Even though the substrates are aligned very precisely by alignment equipment, distortion occurs during the joining process. This distortion unfortunately results in the functional units not being properly aligned at all points. Distortion, scaling errors, or, for example, lens defects in the lithography equipment used for structural formation, can result in inaccurate alignment at specific points on the substrates. All thematic fields related to such problems or errors are encompassed under the concept of "overlap" error.

[0008] Therefore, the object of the present invention is to eliminate or at least significantly reduce the aforementioned drawbacks. This object is addressed by the scope of the present invention. Advantageous improved forms of the present invention are described in the dependent claims. The scope of the present invention also includes all combinations of at least two of the features described in the specification, claims, and / or drawings. In the numerical ranges described, numerical values ​​within the stated limits are also disclosed as limit values ​​and can be claimed in any combination.

[0009] The present invention relates to an apparatus for joining a first substrate to a second substrate, wherein the apparatus has at least one deformation device for deforming at least one of the substrates by fluid, and the at least one deformation device is movable.

[0010] The present invention further relates to a method for joining a first substrate to a second substrate, wherein at least one deformation device deforms at least one of the two substrates by fluid, and the at least one deformation device is in motion.

[0011] In one preferred embodiment, at least one deformation device is provided with a movable hollow pin, which preferably has a central axial hole.

[0012] In another preferred embodiment, at least one deformation device is identified as having a movable nozzle.

[0013] In another preferred embodiment, at least one deformation device is identified as having a movable hose.

[0014] In another preferred embodiment, it is specified that at least one motion device is provided or may be provided for moving at least one deformation device.

[0015] In another preferred embodiment, it has been identified that at least one deformation device is located within an opening in the substrate holding device.

[0016] In another preferred embodiment, at least one deformation device is specified to be movable or moved perpendicular to the holding plane of the substrate holder.

[0017] In another preferred embodiment, at least one deformation device is configured to take on at least one retracted position and working position, or at least one deformation device is specified to take on at least one retracted position and working position.

[0018] In another preferred embodiment, it is specified that at least one deformation device is located entirely or at least substantially entirely within the opening of the substrate holder in the retracted position.

[0019] In another preferred embodiment, it has been identified that at least one deformation device protrudes beyond the holding plane of the substrate holder at its maximum position.

[0020] Both substrates are joined to each other by bonding, particularly fusion bonding, advantageously over as much surface area as possible, without distortion and stretching.

[0021] At the heart of this invention is the idea of ​​applying a preload to at least one of the two substrates prior to contact, which is concentric with respect to the center M of the contact surface of the substrate and moves radially outward. In this case, the load only affects the start of contact, while after contact at one section, particularly at the center M of the substrate, the substrate is released and automatically controlled based on the preload to bond to the opposing substrates, thereby harmonizing both substrates as much as possible and bringing them into contact simultaneously.

[0022] In the following, it is defined that each substrate has a bonding surface that is joined to one another.

[0023] The preload is obtained, in particular, by deformation. In this case, the deformation device acts on the surface opposite to the joint surface, and the deformation is controllable by the deformation device.

[0024] Deformation specifically refers to a state different from the initial state of the substrate. The initial state is, for example, the curvature adjusted before contact of the substrate. Preferably, bonding is controlled after contact of the contact surfaces, particularly by controlled control of the fixing part of the substrate. In particular, a suitable fixing part or fixing means is provided.

[0025] The fluid may be a gas, such as N2 and / or a mixture of gases. In less preferred embodiments, it may be a liquid.

[0026] Preferably, at least one deformation device has a movable hollow pin. In this case, the fluid may be blown through the hollow conduit. The hollow pin has, for example, a central axial hole for supplying the fluid from a fluid port. The fluid supply may be provided externally.

[0027] In an alternative embodiment, at least one deformation device has a movable nozzle. This nozzle may have the same cross-section along its entire length, or it may be expanded, tapered, or have another complex shape.

[0028] In another alternative embodiment, it has been specified that at least one deformation device has a movable hose.

[0029] In particular, the device has at least one motion device (actuator) for moving at least one deformation device.

[0030] By means of a controllable air cushion between at least one deformation device and the substrate, in particular the deformation at the points is reduced and the force is not transmitted to the substrate parallel to the substrate surface. Thereby, a particularly gentle deformation of the substrate is achieved. By means of a particularly gentle deformation of the substrate, in particular the overlay error during the bonding process is reduced. Because the uniform force distribution on the substrate reduces local deformations.

[0031] The control is effected in particular by a continuously adjustable adjustment of the distance between at least one deformation device and the substrate during deformation and / or by the pressure of the fluid acting on the substrate.

[0032] Furthermore, the outflow pattern is changed, in particular by the shape of the nozzles or the configuration of at least one deformation device.

[0033] In another preferred embodiment, the fluid may be heated or is heatable before and / or during outflow from at least one deformation device.

[0034] In another preferred embodiment, the fluid consists of a gas mixture that is supplied through a plurality of pipelines, mixed within at least one deformation device, and / or is already mixed before flowing into at least one deformation device.

[0035] At the state (e.g., pressure, temperature, Mach number) given at the outlet opening of at least one deformation device, the velocity of the fluid decreases as the distance to the substrate surface increases. Thereby, the strength of the achievable deformation can be controlled.

[0036] A controllable air cushion between at least one deformation device and the substrate reduces deformation, particularly at points, and prevents forces from being transmitted to the substrate parallel to the substrate surface.

[0037] Parameters, such as pressure, temperature, force, and flow velocity, may be measured and / or adjusted separately, especially when necessary, by appropriate measurement methods and / or sensors.

[0038] In particular, it is advantageous to reduce the so-called effective holding surface of the holding device with respect to the substrate, so that the substrate is only partially supported by the holding device. Thus, less adhesion occurs between the substrate and the holding device due to the smaller contact surface.

[0039] The fixing is performed particularly in the peripheral region of the substrate (especially the upper substrate), thereby providing effective fixation between the retaining contour of the retaining device and the substrate while simultaneously providing the smallest possible effective retaining surface. Consequently, gentle and reliable removal of the substrate is possible because the peeling force required for removing the substrate is kept to a minimum.

[0040] Preferably, at least one deformation device has at least one pressure element that penetrates the retaining contour of the retaining device in order to allow pressure to be applied uniformly, particularly from the center.

[0041] Preferably, at least one deformation device is configured such that the deformation is performed concentrically with respect to the substrate.

[0042] In less-than-ideal embodiments, contact between the two substrates does not necessarily have to occur at the center. In the following description, "contact" generally refers to contact at the center.

[0043] The center, in particular, refers to the geometric center point of the underlying ideal object, compensated for any asymmetry where necessary. In industrially conventional substrates with a notch, the center is the center of the circle surrounding the ideal substrate without the notch. In industrially conventional substrates with a flat side, the center is the center of the circle surrounding the ideal substrate without the flat side. A similar idea applies to arbitrarily shaped substrates. However, in another embodiment, it may be advantageous for the center to mean the centroid of the substrate.

[0044] To ensure precise point contact at the center, preferably, a radially symmetrical fixing section is provided in the upper holding device, which comprises a central hole, a deformation device capable of translational movement within the hole, particularly a nozzle, and a fluid conduit.

[0045] The temperature of the fluid and / or at least one deformation device may be preferably controlled. By controlling the temperature, localized elongation or strain can be reduced or minimized. Localized thermal effects can be used to reduce overlap errors during joining.

[0046] Preferably, the upper and / or lower retaining devices may be heated and / or cooled. A temperature sensor enables temperature measurement and control. The signal from the temperature sensor is supplied to a temperature controller, which can adjust the temperature as needed.

[0047] The method according to the present invention preferably, - The first upper substrate is held by the first holding surface of the first holding device, - The second lower substrate is held by the second holding surface of the second holding device, - The substrate is attached to the retaining surface by fixing elements. - Before bringing the contact surfaces of the substrates into contact with each other, at least one contact surface is curved by at least one deformation device, preferably the fixed upper contact surface is curved. - Specifically, the upper fixing elements can be controlled and switched off, thereby bonding the substrates together across their entire surface. This includes steps, especially sequences.

[0048] Fixed part / fixed element The overlapping error depends particularly on the type and form of the substrate holder and the fixing points of each substrate. International Publication No. 2014 / 191033 discloses several embodiments of a preferred substrate holder that can be referenced. In the disclosed process, the release of the substrate from the substrate holder after the fixing points, especially the vacuum fixing points, have been released is of paramount importance.

[0049] The fixing part, in particular, - Mechanical fastening parts, especially fastening parts, - In particular, a vacuum station having individually controllable vacuum paths or interconnected vacuum paths, - Electrical fixing parts, especially electrostatic fixing parts, - Magnetic fixing part, - Adhesive fixing part That's fine.

[0050] The fixed part is particularly electronically controllable.

[0051] The vacuum fixing section is the most preferred form of fixing section. Preferably, the vacuum fixing section consists of a plurality of vacuum paths opening on the surface of the substrate holding device. These vacuum paths are preferably individually controllable.

[0052] The radially symmetrical fixing / holding portion is a vacuum hole, circular vacuum lip, or equivalent vacuum element provided to secure the substrate.

[0053] In another preferred embodiment, the fixing elements are grouped into multiple zones, which are individually switchable on and off and / or located on the outer edge of the substrate, and the zones are preferably distributed at equal intervals from one another and located on the outer edge of the substrate. Advantageously, the zones allow for switching larger areas on and off. This makes it possible to simplify the peeling or control of the fixing elements. Peeling of the substrate is preferably controlled from the inside out by switching the individual fixing elements off from the inside out.

[0054] In another preferred embodiment, the substrate is fixed exclusively at its outer edge.

[0055] contact Advantageously, the convex curvature makes it possible to curve, preferably, the upper substrate toward the lower substrate which is located opposite it.

[0056] In a preferred embodiment, the contact axis extends through the center of one substrate, preferably through the centers of both substrates. Thus, in a preferred embodiment, contact between substrates begins at the center of the substrates and preferably extends along the contact axis to the entire outer edge of the substrates. By extending the contact along the contact axis to the entire outer edge of the substrates, advantageously, uniaxial contact can be made along the entire width of the substrates.

[0057] In another preferred embodiment, the curvature of both substrates is specified to be mirror-symmetric with respect to each other. Mirror symmetry means a mirror image with respect to a plane located between the substrates. The plane is, in particular, parallel to the bonding plane that will be formed after bonding. Advantageously, when both substrates are curved mirror-symmetrically with respect to each other, particularly precise contact is possible because, in this case, the substrates can make precise contact at their respective raised points.

[0058] substrate The substrate is preferably radially symmetric. The substrate may have any diameter, in particular, the substrate diameter being 1 inch, 2 inches, 3 inches, 4 inches, 5 inches, 6 inches, 8 inches, 12 inches, 18 inches, or greater than 18 inches.

[0059] The thickness of the substrate is 1 μm to 2000 μm, preferably 10 μm to 1500 μm, and more preferably 100 μm to 1000 μm. In special embodiments, the substrate may have a rectangular shape or a shape other than at least a circular shape. The term "substrate" specifically refers to a semiconductor wafer.

[0060] Actuator Preferably, at least one deformation device may be provided in the substrate holding device and may be raised and / or lowered, particularly through a central hole.

[0061] Preferably, the upper substrate is deformed.

[0062] In a first preferred embodiment, at least one deformation device is moved by a vertical drive device in a vertical relative motion with respect to the substrate holder. The at least one deformation device is moved between a first retracted position (P0) distal to the substrate, particularly housed in an opening or hole, and a second position (P1) in which the deformation device may be extended to its maximum extent perpendicular to the holding surface.

[0063] The instantaneous working position PA for supplying fluid to the back surface of the substrate is located between P0 and P1. The position of at least one deformation device, the position of the fluid due to the outflow, and the deformation of the substrate are preferably measured by sensors and controlled by adjustment loops or adjustment means.

[0064] First, at least one deformation device is advanced toward the substrate. Fluid flows out from at least one deformation device. The at least one deformation device deforms the substrate via a fluid cushion formed by the fluid, rather than directly contacting the back surface of the substrate during the bonding process. The cushion between at least one deformation device and the substrate reduces point deformation and prevents forces from being transmitted to the substrate parallel to the substrate surface. The fluid velocity, pressure, and position of at least one deformation device are measured and adjusted to control the deformation of the substrate.

[0065] At least one deformation device may preferably be returned to or adjusted to any working position PA, for example, if the strength of deformation needs to be adjusted afterward. In parallel with this, the pressure of the outflowing fluid may also be adjusted afterward. Thus, the forces acting on the back surface of the substrate can be controlled with extreme precision before, during, and after the bonding process.

[0066] When the bonding process is complete or bending or pressure is no longer required, the fluid supply is terminated and at least one deformation device is retracted into the opening of the substrate holder (position P0).

[0067] In particular, if deformation needs to be interrupted or if at least one deformation device is obstructed within the holding device, the movable deformation means is retracted to a retracted position P0 within a hole provided in the substrate holding device. Alternatively, at least one deformation device may be returned to or adjusted to any working position PA, for example, if the strength of deformation needs to be adjusted afterward.

[0068] In another embodiment, the lower substrate holder and / or the upper substrate holder, preferably the lower substrate holder, may be moved vertically to control and bring the substrate surfaces of the lower and upper substrates closer together in the vertical direction.

[0069] At least one deformation device may be guided toward the substrate surface through an opening, particularly a hole, provided in the substrate holder by at least one moving device, such as a lifting device. If necessary, a closing element, particularly a seal, can be used to seal the opening of the substrate holder toward at least one deformation device.

[0070] The movement of at least one deformation device between the working position PA and the retracted position P0 may be carried out in various different forms.

[0071] In particular, at least one deformation device may be attached to a lever arm. In another embodiment, this lever arm may perform a rotational or tilting motion to move at least one deformation device.

[0072] The motion of at least one deformation device is preferably controlled with great precision and performed at different speeds. The motion is preferably performed at speeds in the range of 0.1 μm / s to 0.5 μm / s.

[0073] At least one deformation device may be driven in various forms, for example, by a mechanical, electric, hydraulic, and / or pneumatic drive.

[0074] The control (x, y, z, θ) of at least one deformation device may preferably be synchronized with the fluid flow.

[0075] Further advantages, features, and details of the present invention will become apparent from the following description of preferred embodiments and the drawings. [Brief explanation of the drawing]

[0076] [Figure 1a] This is a schematic cross-sectional view of the upper substrate holding device of a preferred embodiment of the apparatus according to the present invention, which is equipped with a deformation device in the retraction position P0. [Figure 1b] This is a schematic cross-sectional view of Figure 1a, showing the deformation device at position P1, which is the maximum possible extension position. [Figure 1c]This is a schematic plan view of a substrate holding device of a preferred embodiment of the apparatus according to the present invention, including the cutting line AA. [Figure 2a] This is a schematic cross-sectional view of a preferred apparatus according to the present invention in a first method step according to the method of the present invention. [Figure 2b] This is a schematic diagram of the apparatus in Figure 2a in the second method step, after the upper substrate holding device and the lower substrate holding device have been brought closer together. [Figure 2c] This is a schematic cross-sectional view of the upper substrate holding device in the third method step during the deformation of the upper substrate, in which at least one deformation device deforms the substrate via a fluid cushion rather than directly contacting the back surface of the substrate during the bonding process (detailed view). [Figure 3a] This is a schematic cross-sectional view of the apparatus according to the present invention in a third method step, during which the upper substrate is deformed via a fluid cushion and brought into central contact with the lower substrate. [Figure 3b] This is a schematic cross-sectional view of the apparatus according to the present invention in the fourth method step of bonding waves, where the upper substrate is detached from the substrate holder by the disconnection of the vacuum fixing section, and at least one deformation device remains in the working position or is post-adjusted. [Figure 3c] This is a schematic cross-sectional view of the apparatus according to the present invention in the fifth method step of bonding waves, where the upper substrate is detached from the substrate holder by the disconnection of the vacuum fixing section, and at least one deformation device is returned to the retracted position. [Figure 3d] This is a schematic cross-sectional view of the apparatus according to the present invention in the sixth method step after the joining process has been completed.

[0077] In the diagram, identical components or components having the same function are denoted by the same reference numeral.

[0078] Figure 1a shows the upper first substrate holding device 1 equipped with a movable deformation device 3 in the retracted position P0. The holder 1k has a structure having a holding surface 1u within the holding plane E. Preferably, only an annular section 9 on the outside of the holding surface 1u is provided for fixing the substrate by a fixing element shown as a vacuum path 8.

[0079] The radius of the retainer 1k may be larger than the radius Ru of the retaining surface 1u, particularly due to the annular shoulder section recessed relative to the retaining surface 1u, as shown in the embodiment in Figure 1a. The radius Ru of the retaining surface 1u is approximately equivalent to the radius of the substrates to be joined together.

[0080] The substrate holding device 1 has a central opening 6 through which a deformation device 3, which is equipped with a fluid conduit 4 and a fluid outlet opening 5, is guided. The deformation device 3 is controlled by a motion device 7.

[0081] The apparatus for performing the bonding process preferably has sensors (not shown) for monitoring and controlling the bending of the substrate and the bonding process. The temperature of the fluid flow and / or the temperature of the deformation apparatus 3 may be controlled.

[0082] By adjusting the temperature, localized elongation or strain can be reduced or minimized. Preferably, the substrate holding devices 1 and 2 may be heated and / or cooled. Temperature sensors enable temperature measurement and control. The signal from the temperature sensor is supplied to a temperature controller (not shown), which allows the temperature to be adjusted as needed. To control and deform the substrate, additional sensors enable measurement and adjustment of flow velocity, pressure, and the position of the deformation device 3.

[0083] Figure 1b shows a cross-sectional view of the upper substrate holding device 1 of the apparatus according to the present invention, which is equipped with a deformation device 3 in a position P1 that can extend to its maximum extent.

[0084] In a preferred embodiment, the deformation device 3 has a specific motion device 7, particularly a specific vertical drive device, for relative vertical movement with respect to the holding device 1. The deformation device 3 is moved between a first retracted position (P0) distal to the substrate, as shown in Figure 1a, where the deformation device 3 is housed within the opening, and a second position (P1), as shown in Figure 1b, where the deformation device 3 may be extended to its maximum extent perpendicular to the holding surface. The working position PA of the deformation device 3 is between P0 and P1.

[0085] The deformation of the substrate 10 is preferably controlled by continuously adjustable adjustment of the distance of the deformation device 3 to the substrate 10 during deformation, and / or by the pressure of the fluid acting on the substrate 10, and / or by changing another parameter.

[0086] In an independent embodiment, the deformation device 3 can not only perform vertical relative motion (Z direction) with respect to the substrate holding device 1, but can also perform tilting motion at a predetermined angle Θ. The XY plane is defined in particular by the holding plane E shown in Figures 1a and 1b.

[0087] The Z direction is perpendicular to the XY plane. In this particular embodiment, the apparatus according to the present invention has a deformation device 3 (not shown) configured to perform translational motion and, in particular additionally, rotational motion.

[0088] In another embodiment, the deformation device 3 can be additionally XY aligned. This links the motion (X,Y,Z,Θ) of the deformation device 3 to the precise detection of its position relative to the substrate 10, thereby achieving extremely precise control of the deformation and, consequently, the most accurate and gentle deformation possible for at least one of the substrates 10 and 11 to come into contact with each other.

[0089] Figure 1c shows a plan view of the substrate holding device 1 where the central opening 6 for guiding the deformation device 3 can be seen. In this embodiment, only the outer annular section 9 of the holding surface 1u for fixing the substrate by the vacuum path 8 is provided.

[0090] In the first process step of the first embodiment of the method according to the present invention shown in Figure 2a, two substrates 10 and 11 are aligned, that is, the first substrate 10 is positioned in the first / upper substrate holder 1, and the second substrate 11 is positioned in the second / lower substrate holder 2, and fixed by a vacuum fixing unit. In this case, the supply of the substrates 10 and 11 may be done manually, but preferably it can be done automatically by a robot.

[0091] The upper substrate holder 1 has a movable deformation device 3 for precisely, and in particular, controllably deforming the upper substrate 10 by an adjustable force. The upper substrate holder 1 has, in particular, at least one opening 6. Through this opening 6, the deformation device 3, in particular a connecting pin 3 equipped with a fluid conduit 4 and a fluid outlet opening and / or nozzle 5, can deform the upper substrate 10. The deformation device 3 is controlled by a motion device 7.

[0092] In the embodiment shown in Figure 2a, the upper substrate holder 1 is only provided with an annular section 9 on the outer edge of the holding surface 1u for fixing the upper substrate 10 by a vacuum path 8, whereas the lower substrate 11 is fixed over its entire surface to the lower substrate holder 2 by a vacuum path 8'.

[0093] The substrates 10 and 11 are first precisely positioned for accurate alignment and then separated and held with a gap h between them, for example, during the exhaust and / or inert gas purging process.

[0094] In the second process step shown in Figure 2b, the relative approach of the substrate holders, in particular, brings the two substrates 10 and 11 closer together. Preferably, the lower substrate holder 2 is lifted, thereby actively bringing the lower substrate 11 closer to the upper substrate 10. However, active approach of the upper substrate holder 1 to the lower substrate holder 2 or simultaneous approach of both substrate holders 1 and 2 to each other is also possible.

[0095] In this case, the distance h between the upper substrate 10 and the lower substrate 11 is reduced to a precisely defined distance h'. The proximity of both substrates 10 and 11 to each other is particularly limited to a distance h' of 1 μm to 2000 μm, preferably 1 μm to 1000 μm, more preferably 5 μm to 200 μm, and most preferably 10 μm to 100 μm. The distances h and h' are defined as the minimum vertical distance between two surface points of the substrates 10 and 11.

[0096] The overlapping error depends particularly on the gap between the two substrates 10 and 11 immediately before the start of the bonding process. The gap between the substrates is a function of position as long as the upper substrate 10 is deformed by the deformation device 3 with a first controllable force.

[0097] In particular, the gap between substrates is greatest at the edges. The smallest gap is in the region of the largest convexity of the deformed substrate 10. As a result, the shape of the deformed substrate also affects the overlapping error.

[0098] The spacing between substrates at the edges is adjusted immediately before bonding to less than 5 mm, preferably less than 2 mm, more preferably less than 1 mm, most preferably less than 0.5 mm, and most preferably less than 0.1 mm. The spacing between substrates on the underside of the largest protrusion is adjusted immediately before bonding to less than 1 mm, preferably less than 100 μm, and more preferably less than 30 μm. Preferably, this spacing is adjusted to 10-20 μm.

[0099] In the third process step shown in Figure 2c, the deformation device 3, equipped with a fluid conduit 4, influences the back surface of the upper substrate 10 via a fluid cushion, causing deformation, particularly a deflection called a concave from the side of the deformation device 3 (i.e., from above). The deformation device 3 applies a first adjustable force to the upper substrate 10, which is particularly greater than 1 mN, preferably greater than 10 mN, more preferably greater than 50 mN, most preferably greater than 100 mN, but particularly less than 5000 mN.

[0100] This force is too weak to detach the substrate 10 from the substrate holder 1, but strong enough to generate the desired deflection. A controllable fluid cushion between the deformation device 3 and the substrate reduces point deformation, preventing the force from being transmitted to the substrate parallel to the substrate surface.

[0101] A fluid cushion, particularly an N2 gas cushion, between the deformation device 3 and the substrate 10 prevents force from being transmitted to the substrate parallel to the substrate surface, resulting in a larger contact area. This reduces localized substrate deformation. Parameters, such as pressure, temperature, force, and velocity, are measured as needed by appropriate measurement methods and / or sensors and may be separately controlled in closed-loop and open-loop configurations. Sensors include, for example, a flow velocity sensor, and for the deformation device 3, a position sensor (not shown).

[0102] Prior to bonding, pre-bonding, or contact, the substrates 10 and 11 may be heated by heating means and / or cooled by cooling means as necessary, i.e., their temperature may be controlled (not shown).

[0103] The order of the second and third process steps is not mandatory, and they may be performed in reverse order.

[0104] As shown in Figure 3a, the fourth process step involves applying further force to the substrate 10. In the first procedure according to the present invention, a second adjustable force is applied to the substrate 10 by increasing the fluid pressure. This results in point contact at the center of the upper substrate 10 with the lower substrate 11.

[0105] The gas pressure ranges from 0.01 bar to 8 bar.

[0106] Alternatively, instead of or in addition to further approach of the deformation device 3 and / or a controlled increase in fluid pressure, the lower substrate holder 2 may be moved upward in the Z direction, thereby resulting in further pressure increase or further approach of the substrate surfaces.

[0107] In this case, the deformation device 3 is moved between a first retracted position (P0) distal to the substrate where the deformation device 3 is housed within the opening 6, and a second position (P1) in which the deformation device may be extended to its maximum extent perpendicular to the support surface. The instantaneous working position PA for supplying fluid flow to the back surface of the substrate 10 is between P0 and P1. The position of the deformation device 3 and / or the position of the fluid flow and / or the deformation of the substrate 10 are preferably measured by sensors and controlled by adjustment loops and adjustment means.

[0108] In this case, in particular, the propagation of the advancing junction wave is monitored.

[0109] Figures 3b and 3c show the change in the position of the deformation device 3 from the working position PA2 shown in Figure 3b to the working position PA3 shown in Figure 3c.

[0110] By controlling and changing the position and / or fluid pressure of the deformation device 3, the upper substrate 10 can be deformed as gently as possible, allowing for controlled contact and control of the propagation of bonding waves. The controlled changes in the position and / or fluid pressure of the deformation device may be adjusted after contact, during the propagation of bonding waves, or during the precise release of the fixing portion 8 of the substrate 10.

[0111] In the fifth process step shown in Figure 3b, the fixing part 8 of the upper substrate holder 1 is switched off. The upper substrate 10 can also be separated by the precise release of the fixing part 8. In particular, in a vacuum fixing part consisting of multiple individually controllable vacuum paths, the precise release of the fixing part is achieved by the continuous release of vacuum, particularly from the center to the edge. The process step is initiated when one of the multiple parameters of the measuring means reaches a preset / adjusted or adjustable value.

[0112] As shown in Figures 3b and 3c, after the deformed and bent substrate 10 (towards the opposing substrate 11) is released, a continuous, uniform, and especially at least primarily automatic bonding occurs along the bonding front, with minimal force and thus minimal strain, due to the advance of the bonding wave. In other words, apart from the fixing at the bonding start point, the upper substrate 10 is not affected by additional fixing after the bonding starts and after release at the bonding start point and can move freely.

[0113] After the substrate 10, which has been deformed and bent (towards the opposing substrate 11), is released, the bonding wave may preferably be controlled in particular with respect to its speed. Speed ​​control is indirectly achieved, in particular, through the composition and / or density and / or temperature of the gas in the atmosphere in which the bonding takes place.

[0114] Although the method according to the present invention is preferably required to be carried out in a low-pressure atmosphere, and more preferably in a vacuum, it may be advantageous to carry out the bonding process in a different atmosphere. In the point contact embodiment shown in Figure 3b or Figure 3c, the bonding wave propagates radially symmetrically from the center to the side edge during bonding, pushing the annular gas cushion forward during this process.

[0115] The strong bonding force prevents the encapsulation of air bubbles. Therefore, in a preferred embodiment, the upper substrate 10 is placed on a kind of gas cushion during the bonding process. By selecting the gas or gas mixture, it is determined how quickly and strongly the upper substrate 10 can be lowered and / or stretched. Additionally, the speed of the bonding wave can also be controlled through the properties of the gas or gas mixture. In this case, according to the present invention, the atmosphere can be controlled to control the bonding speed by selecting the gas or gas mixture and the pressure and / or temperature.

[0116] In the sixth process step shown in Figure 3d, the use of the deformation device 3 is stopped. In this case, the fluid flow is cut off and the deformation device 3 is retracted. The deformation device 3 is retracted into an opening provided in the substrate holding device 1, for example, to the retraction position P0. The process step is initiated when, in particular, one of the multiple parameters of the measuring means reaches a preset / adjusted or adjustable value.

[0117] Finally, the substrate stack may be removed from the lower substrate holder 2 or bonding device by gripping with a robotic arm (not shown) after the lower fixing means 8' is switched off. [Explanation of symbols]

[0118] 1,2 Substrate holding device 1k holding body 1u holding surface 3. Transformation device 4 Fluid line 5 nozzles 6 aperture 7 Exercise equipment 8,8' Fixing means 9. Ring section 10,11 circuit boards 12 board stack P0 Retraction position P1: The position where maximum advancement is possible. PA1,PA2,PA3 Working position E holding plane h,h' interval Ru (Circular Radius) AA cutting line

Claims

1. An apparatus for joining a first substrate (10) to a second substrate (11), comprising at least one deformation device (3) for deforming the first substrate (10) and / or the second substrate (11) with a fluid, The first substrate (10) and / or the second substrate (11) are deformed via a fluid cushion formed by fluid between them and the at least one deformation device (3). The at least one deformation device (3) is movable, The apparatus is characterized in that at least one deformation device (3) has a movable hollow pin.

2. The apparatus according to claim 1, further comprising at least one motion device (7) for moving the at least one deformation device (3).

3. The apparatus according to claim 1 or 2, wherein the at least one deformation device (3) is located within the opening (6) of the substrate holding device (1, 2).

4. The apparatus according to any one of claims 1 to 3, wherein the at least one deformation device (3) is movable perpendicular to the holding plane (E) of the substrate holding devices (1, 2).

5. The apparatus according to any one of claims 1 to 4, wherein the at least one deformation device (3) is configured to take at least one retraction position (P0) and working positions (PA1, PA2, PA3).

6. The apparatus according to any one of claims 1 to 5, wherein the at least one deformation device (3) is completely positioned within the opening (6) of the substrate holding device (1, 2) in the retracted position (P0).

7. The apparatus according to any one of claims 1 to 6, wherein the at least one deformation device (3) protrudes beyond the holding plane (E) of the substrate holding devices (1, 2) at its maximum position (P1).

8. Control of the deformation of the first substrate (10) and / or the second substrate (11) is: By adjusting the distance of the at least one deformation device (3) relative to the first substrate (10) and / or the second substrate (11) during deformation, and / or The apparatus according to any one of claims 1 to 6, wherein the operation is performed by the pressure of a fluid acting on the first substrate (10) and / or the second substrate (11).

9. A method for joining a first substrate (10) to a second substrate (11), wherein at least one deformation device (3) deforms the first substrate (10) and / or the second substrate (11) by fluid, The first substrate (10) and / or the second substrate (11) are deformed via a fluid cushion formed by fluid between them and the at least one deformation device (3). Move the at least one deformation device (3) A method characterized in that the at least one deformation device (3) has a movable hollow pin.

10. The method according to claim 9, wherein the at least one deformation device (3) is movable perpendicular to the holding plane (E) of the substrate holding devices (1, 2).

11. The method according to claim 9 or 10, wherein the at least one deformation device (3) takes at least one retraction position (P0) and working positions (PA1, PA2, PA3).

12. The method according to any one of claims 9 to 11, wherein the at least one deformation device (3) is completely positioned within the opening (6) of the substrate holding device (1, 2) in the retracted position (P0).

13. The method according to any one of claims 9 to 12, wherein the at least one deformation device (3) protrudes beyond the holding plane (E) of the substrate holding devices (1, 2) at its maximum position (P1).

14. The deformation of the first substrate (10) and / or the second substrate (11) By adjusting the distance of the at least one deformation device (3) relative to the first substrate (10) and / or the second substrate (11) during deformation, and / or The method according to any one of claims 9 to 13, controlled by the pressure of a fluid acting on the first substrate (10) and / or the second substrate (11).

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