Vacuum substrate holder with optimized vacuum seal

Abstract

The invention relates to a vacuum substrate holder (1) for fixing a substrate (13), comprising: a) at least one first fixing element (4, 4 ', 4' '); the substrate (13) has a first fixing element (4, 4 ', 4' ', 4 '''), b) a second vacuum region (5, 5 ', 5'', 5 ''') having at least one second fixing element (4, 4 ', 4'', 4 '''), c) a receiving projection (9) which is arranged at least in the first vacuum region (5, 5 ', 5'', 5 ''') and at least in the second vacuum region (5, 5 ', 5'', 5 '''), the substrate (13) being arranged on a receiving surface provided by the receiving projection (9) in the fixed state, and d) separating the first vacuum region (5, 5 ', 5'', 5 ''') from the second vacuum region (5, 5 ', 5'', 5 '''). And at least one transition region (6, 6 ', 6' ', 6 ''', 6IV, 6V) which is separated from each other by means of at least one sealing structure (10, 10 ', 10' ', 10''', 10IV, 10V), said transition region (6, 6 ', 6' ', 6 ''', 6IV, 6V) being provided with at least one sealing structure (10, 10 ', 10'', 10 ''', 10IV, 10V).

Description

Technical Field

[0001] The invention relates to a vacuum substrate holder with an optimized vacuum seal as well as a device for bonding and a method for bonding substrates. This is a solution for a multi-zone substrate receiving device for fusion and hybrid bonding. Background Art

[0002] In recent years, substrate receiving devices have found application in bonding facilities for fusion and hybrid bonding that have more than one defined vacuum zone for holding a substrate.

[0003] These vacuum zones are preferably loaded with different vacuum pressures, which results in different degrees of compression of the substrate at the receiving device. Since the holding force or the pressing force of the substrate at the receiving device can influence the course of the bonding wave or, in particular, the (mechanical) stress introduced into the bonding interface during the bonding process, the bonding result, in particular the distortion of the substrate, can be actively influenced by targeted control of the vacuum pressure in the individual zones. In particular, reference is made to the possibilities of vacuum zones in WO 2017 / 162272 A1.

[0004] The abrupt transition from one vacuum region to another can lead to locally abruptly changing stresses and thus to distortions of the bonded wafer pair due to abrupt changes in the framework conditions for the bonding wave.

[0005] In the prior art, two vacuum zones are separated by vacuum seals. A solution to this problem is to divide the vacuum transition into a plurality of zones and to define the levels so that the vacuum transition does not occur abruptly. However, this leads to a considerable increase in the complexity of the sample holder and the associated handling with pneumatic and electronic devices, which is not economically desirable on the one hand and mechanically difficult or impossible to achieve on the other hand, because the construction space is limited and it is impossible or difficult to drill a large number of feed openings in the substrate receiving device. These difficulties are particularly exacerbated when manufacturing substrate holders made of ceramics such as silicon nitride or silicon carbide (SiSiC ceramics).

[0006] For many years, substrates have been connected to one another in the semiconductor industry by so-called bonding processes. Prior to connection, the substrates must be aligned to one another as accurately as possible.

[0007] One of the biggest challenges in bonding is the bonding process itself, i.e. during the time between the start of bonding and the time when the contact surfaces of the substrates are in full contact. Here, the alignment of the two substrates with respect to each other may change significantly relative to the previous alignment. Although the substrates can be aligned very accurately with respect to each other by means of the alignment facility, distortions of the substrates may occur during the bonding process itself. Alignment inaccuracies at a certain point on the substrate may be the result of distortions, scaling errors, lens errors (magnification or reduction errors), etc.

[0008] In particular, sudden changes should be avoided, since sudden distortions caused by the bonding process can be difficult to compensate for with compensation options (e.g. post-bonding lithography). In contrast, gradual distortions can be compensated more easily and at least minimized. The finer the imageable structures, the more strongly the quality of the resulting semiconductor components depends on tolerances, in particular distortions, of the components used.

[0009] In the prior art, there are various methods and devices by means of which attempts can be made to influence the bonding process, for example in EP 2 656 378 B1 or WO 2014 / 191033 A1. Summary of the invention

[0010] The object of the present invention is to provide a device and a method for bonding two substrates, with which the bonding accuracy can be increased and a reduction in the distortion caused by the bonding can be achieved, since abrupt changes in the framework conditions for the bonding wave are avoided.

[0011] The object of the present invention is therefore to at least partially eliminate, in particular completely eliminate, the disadvantages listed in the prior art. In particular, the object of the present invention is to specify an improved vacuum substrate holder and an improved device and method for bonding. Furthermore, the object of the present invention is to provide a vacuum substrate holder with which the bonding accuracy is increased and the distortion caused by bonding is reduced.

[0012] This object is achieved by the features of the parallel claims. Advantageous improvements of the invention are described in the dependent claims. The scope of the invention also includes all combinations of at least two features described in the specification, the claims and / or the drawings. Within the specified value range, values ​​within the limits mentioned should also be regarded as disclosed as limit values ​​and can be claimed in any combination.

[0013] Therefore, the present invention relates to a vacuum substrate holder for fixing a substrate, which has at least: a first vacuum area with at least one first fixing element; a second vacuum area with at least one second fixing element; a receiving protrusion, which is arranged at least in the first vacuum area and at least in the second vacuum area, wherein the substrate is arranged on a receiving surface provided by the receiving protrusion in a fixed state; and at least one transition area separating the first vacuum area and the second vacuum area from each other, wherein the transition area has at least one sealing structure, wherein in the fixed state, the first vacuum area and the second vacuum area are fluidically connected to each other via the transition area.

[0014] In other words, a vacuum substrate holder is provided which provides a receiving surface for a substrate or a substrate stack, with which a gradual vacuum transition between adjacent vacuum zones can be achieved by means of a purposefully adjusted fluid connection in the transition zone. Here, the second zone can also be formed by the environment of the vacuum substrate holder, so that a correspondingly favorable pressure balance can be created at the periphery.

[0015] The receiving protuberances are in particular block-shaped protuberances of the same height, which are arranged over the entire vacuum substrate support, preferably regularly and in each zone. The vacuum zones or the first and second vacuum zones are separated from one another by a transition zone. The transition zone is characterized in particular in that at least one sealing structure is arranged in the transition zone, which seals the individual vacuum zones from one another, wherein in the present case, in contrast to the prior art, a fluid connection between the vacuum zones is provided by the transition zone.

[0016] When the substrate is placed on the receiving protuberance or fixed on the receiving surface, the vacuum zones can only be connected fluidically via the transition zone. Thus, the substrate, the substrate holder and the transition zone of the substrate holder form a vacuum zone. Here, the transition zone is dimensioned so that it can continue to be fixed by the fixing element. Thus, a gradual vacuum transition between the vacuum zones can be ensured without restricting the function of the vacuum substrate holder.

[0017] The at least one fixing element is in particular one or more vacuum openings, which are connected to a correspondingly adjusted vacuum control unit. Advantageously, the substrate can be fixed to the corresponding vacuum zone via at least one fixing element or a plurality of fixing elements. The sealing structure can be, for example, a sealing ring and is configured along the entire transition zone. As is common for vacuum substrate supports, a radially symmetrical arrangement of the elements is preferred, wherein the transition zone is also preferably configured in the form of a circular arc.

[0018] Sudden changes in the vacuum value can advantageously be prevented by the transition zone. In addition, better bonding results can be achieved with a vacuum substrate holder.

[0019] In a preferred embodiment of the vacuum substrate support, it is provided that at least one sealing structure has at least one opening, and the flow cross-sectional area of ​​the sealing structure can be preset by means of the at least one opening. Thus, the sealing structure has one or more desired openings in order to provide a specific flow cross-sectional area through the transition region and thus from the first vacuum region to the second vacuum region. By dimensioning the openings, the flow behavior can be advantageously adjusted and thus a progressive balance can be achieved. In this case, the flow cross-sectional area of ​​the sealing structure preferably also constitutes the flow cross-sectional area of ​​the transition region.

[0020] In a preferred embodiment of the vacuum substrate support, it is provided that at least one transition region has at least two sealing structures in each case, and that the transition region forms a gap between the sealing structures of the at least one transition region that are farthest from each other. In this particularly preferred embodiment, the transition region has at least two sealing structures that are preferably directly adjacent to the respective vacuum region. In this way, the respective adjacent vacuum regions can advantageously be separated along the entire extension of the transition region in the radial direction. In addition, a gap is advantageously provided in which a gradual pressure balance between the first vacuum region and the second vacuum region can be achieved without bonding errors arising due to sudden changes in the vacuum transition.

[0021] Here, the gap can have a further sealing structure between the two sealing structures that are furthest apart. This further enhances the positive influence on the bonding result, since the vacuum transition can be performed even more gradually. Here, preferably, the sealing structures of the same transition zone are at the same distance from each other.

[0022] In a preferred embodiment of the vacuum substrate support, it is provided that the corresponding flow cross-sectional areas of the two sealing structures which are farthest from each other are of equal size. In this way, a particularly gradual vacuum transition can be achieved, since the corresponding openings or flow cross-sectional areas of the corresponding outer sealing structures of the transition zone are dimensioned identically. In addition, the balancing can be carried out uniformly in the direction of the first vacuum zone and the second vacuum zone. Preferably, all sealing structures of the transition zone have the same flow cross-sectional area. Thus, a uniform balancing is advantageously ensured. Therefore, the corresponding flow cross-sectional areas of all sealing structures of at least one transition zone are constructed or dimensioned identically.

[0023] In a preferred embodiment of the vacuum substrate support, it is arranged that the flow cross-sectional area of ​​the gap is larger than the flow cross-sectional area of ​​the sealing structure in the transition zone. In other words, a buffer is thus formed by the gap, because the balance is only carried out via the corresponding openings in the sealing structure, and at least one flow cross-sectional area is provided in the transition zone that is larger than the flow cross-sectional area of ​​the sealing structure located outside. If more than two sealing structures or additional sealing structures are arranged between the sealing structures located outside, the flow cross-sectional area of ​​the gap is determined at the location without the sealing structure. Therefore, the volume provided by the gap between the sealing structures located outside advantageously provides space for balancing the vacuum. Here, the volume of the gap and the flow cross-sectional area can be advantageously adapted by filling the gap with material.

[0024] In a preferred embodiment of the vacuum substrate support, it is arranged that the flow cross-sectional area of ​​the gap is 5 times, preferably 10 times, preferably 30 times, more preferably 50 times, even more preferably 100 times, most preferably 200 times, and most preferably more than 200 times the flow cross-sectional area of ​​the sealing structure of the transition zone.

[0025] In other words, the opening in the seal is significantly smaller than the cross section of the gap.

[0026] In a preferred embodiment of the vacuum substrate support, it is provided that at least one sealing structure has a uniform height relative to the vacuum substrate support surface, and the height of at least one sealing structure is less than the height (H) of the receiving protrusion relative to the vacuum substrate support surface, so that in the fixed state, a gap with a gap height (h) is constructed between at least one sealing structure and the substrate. In other words, the height of the sealing structure of the transition zone is the same along the transition zone. Therefore, the gap between the substrate and the sealing structure is also the same. Therefore, the sealing structure is set back compared to the receiving surface provided by the receiving protrusion. Therefore, the sealing ring is particularly suitable for this embodiment. The vacuum seal can be set back, for example, between 100nm and 5μm, preferably between 100nm and 3μm, more preferably between 100nm and 500nm. In contrast, the height H1 of the nodule that defines the height of the support surface of the substrate is, for example, between 100μm and 1000μm. In this way, a gap of the same size is provided along the entire transition zone, thereby ensuring a particularly uniform vacuum transition, wherein the aforementioned area has proven to be particularly suitable for this application.

[0027] In a preferred embodiment of the vacuum substrate support, it is provided that the gap height is less than 1 / 10, preferably less than 1 / 30, more preferably less than 1 / 50, even more preferably less than 1 / 80, most preferably less than 1 / 100, and most preferably less than 1 / 200 of the height of the receiving protrusion. Here, the height of the receiving protrusion is also determined by the surface of the vacuum substrate support. In the fixed state of the substrate, this height corresponds in particular to the distance between the substrate and the surface of the vacuum substrate support. Therefore, the gap also predetermines the flow cross-sectional area of ​​the corresponding adjacent sealing structure. It has been proven that the above-mentioned size ratio is particularly suitable for a gradual vacuum transition and can therefore achieve very good bonding results. The absolute height of the receiving protrusion is less than 2000 μm, in particular less than 1000 μm, preferably less than 500 μm, more preferably less than 200 μm, and most preferably less than 100 μm.

[0028] In a preferred embodiment of the vacuum substrate support, it is provided that linear protrusions with uniform axial distances are arranged on at least one sealing structure along the transition region. In this case, the linear protrusions preferably extend along the entire transition region on the sealing structure. The linear protrusions are taken into account when determining the height of the sealing structure. Balancing can be achieved even more uniformly by means of the linear protrusions. In this case, preferably, more than two, more preferably more than three linear protrusions are arranged on the sealing structure at the same distance from one another.

[0029] Here, in one embodiment, the transition zone can be provided by a sealing structure having wide and multiple linear protrusions. Preferably, in this embodiment, the transition zone has only one sealing structure.

[0030] In a preferred embodiment of the vacuum substrate holder, it is provided that the at least one sealing structure in the fixed state at least partially bears against the substrate and that the channel is formed offset along the transition region in the at least one sealing structure.

[0031] Therefore, a sealing structure or multiple sealing structures in the transition zone do not deflect backward and contact the substrate. The channel is also an opening like a gap and can be constructed arbitrarily. Preferably, the channel has a circular or rectangular cross-section. In this case, the channel forms a flow cross-sectional area. Here, it is particularly preferred that multiple sealing structures in the transition zone and particularly preferably all sealing structures have channels. The channel is preferably arranged at the surface facing the substrate of a sealing structure or multiple sealing structures. Therefore, the substrate is not placed on the sealing structure in the region of the channel. It is particularly preferred that all sealing structures in the transition zone have channels, which are preferably arranged regularly offset along the transition zone or along the radius, thereby increasing the flow path. In this way, a particularly gradual vacuum transition and a particularly twist-free bonding result can be achieved.

[0032] In a preferred embodiment of the vacuum substrate support, it is arranged that the distance between at least one first vacuum zone and at least one second vacuum zone is less than 50 mm, preferably less than 25 mm, more preferably less than 20 mm, most preferably less than 15 mm, and most preferably less than 10 mm. In other words, the transition zone is sized accordingly. In a circular vacuum substrate support, the distance is radially sized, and the transition zone, which is particularly configured as an arc, has a radial extension corresponding to the aforementioned value. Due to the specific distance between radially adjacent vacuum zones, a gradual transition can be advantageously achieved in a common substrate support diameter. In addition, the flow cross-sectional area of ​​the gap can also be provided within a certain range along the radial extension, so that the minimum or maximum volume of the gap can be provided. It has been confirmed that the distance between the vacuum zones is particularly suitable for achieving a gradual vacuum transition.

[0033] In a preferred embodiment of the vacuum substrate support, it is arranged that at least one fixing element of the vacuum zone has at least one fluid opening respectively, and wherein the total flow area of ​​the corresponding vacuum zone is jointly constructed by all the fluid openings of the corresponding vacuum zone, and wherein the flow cross-sectional area of ​​the sealing structure of the transition zone adjacent to the corresponding vacuum zone is 1 / 2, preferably 1 / 5, more preferably 1 / 10, still more preferably 1 / 30, most preferably 1 / 50, and most preferably 1 / 100 of the total flow area of ​​the fixing element of the corresponding adjacent vacuum zone. The fixing element has one or more fluid openings to flood or evacuate the corresponding vacuum zone. The total flow area is preset by the total area of ​​all fluid openings of the fixing element of the vacuum zone. In other words, the flow cross-sectional area of ​​the supply line of the transition zone is significantly larger than the flow cross-sectional area of ​​the sealing structure of the adjacent transition zone or multiple transition zones. In this way, a gradual vacuum transition can be advantageously adjusted according to the parameters of the fixing element.

[0034] In a preferred embodiment of the vacuum substrate holder, it is provided that the flow cross-sectional area of ​​the sealing structure is less than 1 / 10, preferably less than 1 / 30, more preferably less than 1 / 50, even more preferably less than 1 / 80, most preferably less than 1 / 100, most preferably less than 1 / 200 of the total opening area between the receiving protuberances of the vacuum zone directly adjacent to the transition zone. Here, the total opening area is preferably determined perpendicularly to the substrate in the fixed state. The total opening area of ​​the vacuum zone toward the transition zone is predetermined by the free area between the receiving protuberances. In other words, the minimum area between the nodes of the respective vacuum zone adjacent to the transition zone (i.e. the flow path of the fluid in the direction of the transition zone) forms the total opening area. In this way, a particularly gentle and torsion-free bonding process can be performed with the vacuum substrate holder.

[0035] In a preferred embodiment of the vacuum substrate support, it is provided that the vacuum substrate support has further vacuum regions, wherein the further vacuum regions are respectively separated by further transition regions, and wherein the vacuum regions adjacent in the radial direction are respectively fluidically connected to each other via further transition regions. In other words, a plurality of vacuum regions can be connected in series or fluidically connected to each other. Here, the transition regions are preferably arranged in the direction of the intended direction of movement of the bonding wave. Here, respectively radially adjacent vacuum regions are respectively separated by transition regions. In this embodiment, the further features can be applied to analogs in a technically reasonable manner and have the same, in particular further enhanced, advantages.

[0036] The invention further relates to a device for bonding substrates, which has at least a vacuum substrate holder. The vacuum substrate holder is particularly suitable for use in a bonding device. In this case, in particular the lower substrate holder is designed as a vacuum substrate holder and provides a gradual vacuum transition between the corresponding vacuum zones. In this case, the bonding accuracy is significantly improved.

[0037] The invention further relates to a method for bonding substrates, comprising the following steps, in particular in the following order: i) providing a first substrate on a vacuum substrate holder, ii) providing a second substrate on the substrate holder, and iii) bonding the first substrate to the second substrate. In particular, the pressure differences occurring during the bonding in step iii) are compensated in the corresponding vacuum regions of the vacuum substrate holder, in particular along the advancing bonding wave between the first substrate and the second substrate, via at least one transition region.

[0038] A particularly important aspect of the invention is to achieve a gradual vacuum transition from one vacuum zone to the next in the region of the receiving surface of the receiving device or the vacuum substrate holder. This reduces the distortion caused by bonding (English: Bonding Induced Distortion) because abrupt changes in the framework conditions for the bonding wave are avoided.

[0039] By targeted structuring or by means of a transition zone, a gradual vacuum transition between two vacuum zones can be achieved. A gradual vacuum transition from one vacuum zone to the other is achieved by introducing a transition zone with a larger flow cross section in the region of the transition zone than in the region of the vacuum seal.

[0040] The transition region is particularly preferably not actively supplied with vacuum and does not have any fixing elements.

[0041] The vacuum substrate holder enables a controlled, gradual vacuum transition from one vacuum zone to the next. The transition zone between two vacuum zones enables a gradual vacuum transition from the respective first vacuum zone to the second vacuum zone. The change of the substrate holder from one vacuum zone to another is achieved by a generated gradual vacuum transition with the possibility of design optimization, so that the framework conditions for the bonding wave also change gradually. This reduces and equalizes distortions, which leads to an improved quality of the bonded product.

[0042] During bonding, in particular during the propagation of the bonding wave, preferably in fusion and hybrid bonding, both substrates are held by the receiving device.

[0043] An important aspect is to fix the substrates to be bonded on a receiving device with multiple vacuum zones, which achieve a gradual vacuum transition from one vacuum zone to the next in the holding surface of the receiving device by means of transition zones. This reduces the distortion caused by bonding, since abrupt changes in the framework conditions for the bonding wave are avoided by the balanced fixing.

[0044] In a preferred embodiment, at least one of the two substrates is bent before contact or bonding, and the curvature of at least one of the two substrates is changed during bonding, especially during the propagation of the bonding wave, by controlling the curvature. The curvature change refers in particular to a state that deviates from the initial state of the substrate. The curvature of at least one of the substrates is described in detail in WO2017 / 162272A1. Therefore, its precise description is omitted here.

[0045] In this case, the bonding is controlled, in particular after contacting the contact surface, in particular by controlled fixing of the substrate.

[0046] In this case, between each of the two vacuum regions there is a transition region without fastening elements which is not actively supplied with vacuum.

[0047] A further aspect of the invention is the use of, in particular, individually switchable fixing elements, by means of which the advancing bonding wave between the contact surfaces can be controlled or regulated in a controlled manner.

[0048] A characteristic process in bonding, in particular permanent bonding, preferably fusion bonding, is the most central and / or punctiform contact of the two contact surfaces of the substrates. In general, the contact of the two substrates can also be carried out non-centrally.

[0049] By designing the fixation of the two substrates together with monitoring, controlling or regulating the curvature and / or separation of at least one of the two substrates, the advancing bonding wave can be controlled in such a way that optimal, continuous, in particular advancing contact of the two substrates along the contact surface is achieved.

[0050] Optimal contact is particularly understood as a local alignment error ("jump" error) at each location of the contact interface between the two substrates being minimal, or even vanishing in the best case. Different runout errors are described in detail and referenced in WO2014 / 191033A1.

[0051] Therefore, the present invention relates in particular to a method and a device, by means of which two substrates can be bonded to each other in such a way that distortion, in particular distortion caused by bonding, is minimized because abrupt changes in the framework conditions for the bonding wave are avoided. Here, a substrate is fixed by a plurality of fixing elements, in particular divided into vacuum zones. Thus, a gradual vacuum transition from one vacuum zone to the next is achieved in the holding surface of the receiving device through a transition zone. The transition zone is not supplied with vacuum and serves as a gap between two different vacuum zones. The vacuum appears in the gap or transition zone through leakage at the vacuum seal. Here, the transition zone acts in a balanced manner because different leakage rates at different positions along the vacuum seal can be balanced via the seal and / or structure in the transition zone. By balancing the substrate fixation from one vacuum zone to another by the generated gradual vacuum transition, the framework conditions for the bonding wave will also change gradually. Distortion is thereby reduced and balanced, which leads to improved quality of the bonded product.

[0052] After the contact of the centers of the two substrates is achieved, the fixing means of the receiving device are particularly manipulated in such a way that a controlled deformation / curvature change of at least one of the substrates is achieved. The upper substrate is pulled downward in a controlled manner by gravity on the one hand and by the bonding force acting along the bonding wave and between the substrates on the other hand. As a result, the upper substrate is connected to the lower substrate radially from the center toward the side edge. This results in the construction of a radially symmetrical bonding wave, which extends in particular from the center to the side edge. It is also conceivable that during the entire time period in which the bonding wave is running, the upper substrate remains fixed, and the advancement of the bonding wave can be promoted by continuously disconnecting the fixing elements, in particular starting with the fixing elements in the interior of the substrate holder. The continuation of the bonding wave can also be promoted in particular by the following means, that is, during the advancement of the bonding wave, the two substrate holders are brought relatively close to each other.

[0053] According to one embodiment of the invention, the fixing element is an arranged vacuum hole, one or more circular vacuum lips or similar vacuum elements, by means of which the wafer or substrate can be fixed.

[0054] Pins or lines in a centrally drilled hole, from which an overpressure can be generated between substrate holder and substrate by introducing gas, can be used to fix the controllable deflection of the substrate (curvature means and / or curvature changing means).

[0055] The substrate can have any shape, but is preferably circular. The diameter of the substrate is particularly standardized in the industry. For wafers, the diameters common in the industry are 1 inch, 2 inches, 3 inches, 4 inches, 5 inches, 6 inches, 8 inches, 12 inches and 18 inches. However, various embodiments can process essentially any substrate, regardless of its diameter.

[0056] The bonding device or the device for bonding has two receiving devices, one for the upper substrate and one for the lower substrate. The two receiving devices are usually not identical, because at least one of the receiving devices has one or more deformation elements in order to deform one of the substrates.

[0057] The receiving device for the upper substrate and the lower substrate has a fixing device, in particular a plurality of fixing elements. The fixing elements can be grouped in the vacuum zone. All fixing elements of the vacuum zone can be switched simultaneously. Preferably, all fixing elements of the vacuum zone can be controlled by a single control element, in particular a control valve.

[0058] In a less preferred embodiment, all fixing elements in a zone can be switched individually. In this way, multiple fixing elements can be operated simultaneously to fix or release the substrate in the zone, or they can be operated individually but generate very unique deformation characteristics of the substrate in its vacuum zone.

[0059] The zones or vacuum zones are dimensioned, in particular, as is customary for zone vacuum substrate supports and can adopt, for example, the following geometries: single-sided, circle segments, tiles, in particular triangles, quadrilaterals or hexagons.

[0060] The fixing means can be controlled in particular electronically. The fixing properties of the holding surface of the receiving device are controlled by the number of fixing elements per unit area and the correspondingly set pressure.

[0061] Here, vacuum fixing is the preferred fixing method. The fixing element can be loaded with negative pressure for fixing. In order to release the substrate, the fixing element can also be loaded with overpressure.

[0062] In a first embodiment, the vacuum fixture consists of a plurality of vacuum rails emerging from the substrate surface of the substrate holder. The vacuum rails can preferably be individually controlled.

[0063] In another embodiment, the fixing element consists of a hole. In another embodiment, the fixing element is provided with a vacuum lip.

[0064] The vacuum tracks and / or vacuum holes are combined into vacuum zones which can be individually controlled and thus evacuated or flooded. However, each vacuum zone is independent of the other vacuum zones. Thus, the possibility of constructing individual vacuum zones which can be individually controlled is obtained.

[0065] The vacuum zone is preferably designed in an annular shape. This enables the substrate to be fixed and / or detached from the receiving device in a targeted, radially symmetrical manner, especially from the inside to the outside. In particular, reference is made to the possibility of the vacuum zone in the printed document WO2017 / 162272A1.

[0066] In another embodiment, the vacuum region is evenly distributed on the holding surface.

[0067] In another embodiment, the vacuum zone is located in the edge region of the holding surface of the receiving device. The edge region extends in particular to half the radius of the holding surface of the receiving device, preferably to a quarter of the radius.

[0068] Furthermore, the use of a receiving device with a pin chuck is disclosed. A pin chuck receiving device is understood to be a receiving device whose surface is not flat but consists of a plurality of small protrusions or receiving protrusions, pin chucks, which form a holding plane and carry the substrate thereon. Such a receiving device is described in detail in the printed documents WO 2015 / 113641 A1 and WO 2017 / 162272 A1, to which reference is made here. The use of such a receiving device is advantageous in that the contact surface between the substrate and the holding surface of the receiving device is as small as possible, thereby reducing contamination of the back side of the substrate to a minimum, or thereby preventing contamination from occurring at all.

[0069] The height of the nodules is in particular less than 1 μm, preferably less than 500 μm, more preferably less than 200 μm, most preferably less than 100 μm.

[0070] In a preferred embodiment, the height of the nodules is between 100 μm and 1000 μm.

[0071] The number of fixing elements per vacuum zone is arbitrary. In particular, there is at least 1 fixing element, preferably at least 2 fixing elements, preferably more than 10, more preferably more than 20, even more preferably more than 50, and most preferably more than 100 fixing elements in the vacuum zone.

[0072] A plurality of vacuum zones arranged in succession can be controlled, in particular activated or deactivated, so that the local fixation of the substrate can be adjusted. In particular, the vacuum zones are activated by switching on all fixing elements in the vacuum zones with a preferably adjustable pressure which predetermines the respective holding force of the zones.

[0073] An important aspect is that between the vacuum zones there are also zones or transition zones without fixing elements and without vacuum supply. These zones are structured in such a way that a gradual vacuum transition from one vacuum zone to the next is achieved in the holding surface of the receiving device.

[0074] The distance between two vacuum zones is in particular less than 50 mm, preferably less than 25 mm, even more preferably less than 20 mm, most preferably less than 15 mm, most preferably less than 10 mm. If the vacuum zones are designed as circle segments, the distance will be the distance between the inner ring of the outer circle segment and the outer ring of the inner circle segment.

[0075] In addition to the mechanical stresses caused by fixing the substrate on a vacuum substrate holder, which may have been generated in the substrate during the pretreatment step, new stress patterns are generated due to the fixing of the substrate. If forces act on a substrate, for example, which is placed on a structure of a holding surface, asymmetric deformations are generated. Forces acting on the substrate are, for example, gravity and the suction of the individual vacuum zones. This asymmetric deformation also exists during the contact between the two substrates and / or during the bonding process and inevitably leads to an asymmetric propagation of the bonding wave front and therefore to undesirable beating effects. The beating effect can be incorporated into the bonding interface as a distortion.

[0076] In this case, there are also surfaces or areas without fixing elements between the vacuum areas, and these surfaces are designed or structured in such a way that a gradual vacuum transition from one vacuum area to the next vacuum area can be achieved in the holding surface of the receiving device. The gradual vacuum transition from one vacuum area to the next vacuum area achieves a reduction in distortions, since abrupt changes in the framework conditions for the bonding wave are avoided.

[0077] In particular, sudden changes in distortions are avoided by changing the framework conditions for the bonding wave gradually rather than suddenly along the different vacuum zones. Sudden changes should be avoided because sudden distortions that occur after the bonding process can be difficult to compensate, for example using compensation possibilities in post-bonding lithography. In contrast, gradual distortions can be more easily partially minimized. The finer the imageable structures, the more strongly the quality of the resulting semiconductor components depends on the tolerances, in particular the distortions, of the components used.

[0078] The gradual vacuum transition from one vacuum zone to the next is achieved by optimizing the design of the surface between the vacuum zones. The surface between the vacuum zones is a surface without fixed elements and is not actively supplied with vacuum. The surface between one vacuum zone and the next is called a transition zone. The individual transition zones between different vacuum zones can be designed differently. Therefore, there are at least two vacuum zones and at least one transition zone on the receiving device.

[0079] The basic idea of ​​the invention is to incorporate a vacuum zone structure or a sealing structure in the holding surface of the receiving device in the region of the vacuum seal between two vacuum zones, which ensures a gradual vacuum transition from one vacuum zone to the next. Preferably, the structure is designed in such a way that this gradual vacuum transition takes place uniformly at all positions along the vacuum seal. The structure can be a structure in the vacuum seal itself, such as a channel, or a vacuum seal that is set back, for example by changing the dimensions, or a structured gap in the region of the transition zone.

[0080] The transition zone permanently allows more or less leakage gas to pass through, similar to a labyrinth or throttling gap seal.

[0081] A leak is an opening or gap in a closed space through which gas can come out (enter in the case of a vacuum). For example, the flow resistance depends on the gap height. Too small a gap height means that the flow resistance is very large. By moving the vacuum seal (e.g. an annular seal) back relative to the support plane of the substrate on the holding surface of the receiving device, the flow cross section in the area of ​​the vacuum seal is determined by the gap height. This flow cross section in the area of ​​the vacuum seal is much smaller than in the area of ​​the support surface, where the flow cross section is determined by the height of the block.

[0082] In the prior art, no transition zone is provided between one vacuum zone and the next. Therefore, a vacuum seal is present between the two vacuum zones. By setting this vacuum seal back relative to the support plane of the substrate on the holding surface of the receiving device, the flow resistance in the region of the vacuum seal remains large compared to the flow resistance in the region of the vacuum zones.

[0083] By introducing a transition zone which has a larger flow cross section in the region of the transition zone than in the region of the vacuum seal, a gradual vacuum transition from one vacuum zone to the other can be achieved.

[0084] The gradual vacuum transition from one vacuum zone to another is determined by the height of the vacuum seal between the two vacuum zones and the structural selection of the transition zone located therebetween. By designing the transition zone and the vacuum seal, the flow resistance in the region of the vacuum seal, in the region of the transition zone and in the region of the vacuum zone is controlled in such a way that an equilibrium is created between the two vacuum zones in the transition zone, because the vacuum in the transition zone is balanced by leakage at the vacuum seal or the structure.

[0085] The setback of the vacuum seal relative to the support plane of the substrate on the holding surface of the receiving device defines the gap height h, which is to achieve leakage. For example, the vacuum seal can be set back between 1 μm and 5 μm, preferably between 1 μm and 3 μm. In contrast, the height of the nodule that defines the height of the support surface of the substrate is, for example, between 100 μm and 1000 μm.

[0086] In one embodiment, more than one vacuum seal, in particular a sealing ring, is placed between two vacuum zones. In this case, the zone between the vacuum seals is not actively supplied with a vacuum. Due to leakage at the vacuum seal, a vacuum occurs in the gap. In this case, the gap acts in a balanced manner, because different leakage rates at different positions along the vacuum seal can be balanced via the vacuum seal. This is especially the case if the flow cross section in the region of the gap is larger than the leakage cross section in the region of the individual vacuum seals. Preferably, these cross sections are optimized for the best possible result. In particular, the gap height for the vacuum seal or structure is optimized. This leads to leakage optimization in the region of the (multiple) vacuum seals.

[0087] In another embodiment, the height of the vacuum seal between the vacuum zone and the transition zone is moved back relative to the surface of the substrate support, especially the block. Here, the distance (gap height) is selected so that it is significantly smaller than the height of the block. The gap height is less than 1 / 10, preferably less than 1 / 30, more preferably less than 1 / 50, more preferably less than 1 / 80, most preferably less than 1 / 100, most preferably less than 1 / 200 of the height of the block. Therefore, it is ensured that the pressure drop mainly occurs in the region of the vacuum seal, and the uniformity of the vacuum in the region of the vacuum zone is given. Another important design criterion is that the cross section of the leakage should be significantly smaller than the cross section of the supply line. The cross section of the leakage is 1 / 2, preferably 1 / 5, preferably 1 / 10, more preferably 1 / 30, more preferably 1 / 50, most preferably 1 / 100, most preferably less than 1 / 100 of the cross section of the supply line. Therefore, it is ensured that leakage is a limiting resistance in the system, and the vacuum value in the region of the support surface (holding surface) can be controlled in a targeted and accurate manner.

[0088] In another embodiment, the vacuum seal between the vacuum zone and the transition zone or the vacuum seal in the transition zone between the two vacuum zones does not move back relative to the surface of the substrate support. Instead, in the vacuum seal, small channels are added at regular distances along the direction at multiple locations. Here, the cross section of these channels is selected so that it is significantly smaller than the cross section in the region of the block. The cross section of the channel is less than 1 / 10, preferably less than 1 / 30, more preferably less than 1 / 50, more preferably less than 1 / 80, most preferably less than 1 / 100, most preferably less than 1 / 200 of the cross section in the region of the block. Therefore, it is ensured that the pressure drop mainly occurs in the region of the vacuum seal, and the uniformity of the vacuum in the region of the vacuum zone is provided. In this embodiment as well, another important design criterion is that the cross section of the leak should be significantly smaller than the cross section of the supply line. The cross section of the leak is 1 / 2, preferably 1 / 5, preferably 1 / 10, more preferably 1 / 30, more preferably 1 / 50, most preferably 1 / 100, most preferably less than 1 / 100 of the cross section of the supply line. It is thus ensured that the leakage is a limiting resistance in the system and the vacuum value in the region of the supporting surface (holding surface) can be controlled in a targeted and precise manner.

[0089] In another embodiment, multiple vacuum seals are used in the transition zone. Thus, additional vacuum seals are arranged between the vacuum seals that define the transition between the vacuum zone and the transition zone. By arranging multiple (at least one) vacuum intermediate seals, the vacuum transition between two vacuum zones supplied with vacuum can be divided and graded in individual vacuum steps.

[0090] In a preferred embodiment, if the resistance of the individual vacuum seals is selected identically or the vacuum seals are manufactured identically, the individual intermediate stages of the vacuum value are evenly distributed.

[0091] In another advantageous embodiment, by selecting the leakage cross section, the vacuum level can be intentionally non-linearly divided, but rather selected according to the requirements of the process. Here, the gap between the vacuum seals acts in a balanced manner, so that the vacuum gradient is as uniform as possible over the entire length of the vacuum seal.

[0092] Here, preferably the flow cross section of the gap is selected to be larger than the cross section of the leakage. In particular, the gap should have a cross section that is 5 times, preferably 10 times, preferably 30 times, more preferably 50 times, even more preferably 100 times, most preferably 200 times, most preferably more than 200 times that of the leakage.

[0093] In another embodiment, the transition region between two vacuum regions achieves shorter evacuation times and shorter ventilation times. In this particularly optimized embodiment, the leakage cross section (gap height) is selected to be as small as possible, so that the cross section of the gap in the transition region can also be small. The small volume of the gap in the transition region has the advantage, in particular, that faster evacuation and ventilation times of the receiving device can be achieved, and thus better performance in dynamic use.

[0094] Another aspect of the invention is to select the distances of the individual vacuum seals in such a way that a vacuum gradient can also be substantially achieved during the travel of the bonding wave. In the case of low contact pressures achieved by low vacuum values, during the travel of the bonding wave, in the region of the contact point between the two substrates, the substrates are partially lifted by the receiving device, which can locally lead to increased leakage in the region of the vacuum seals. The changes in the local vacuum gradient in the transition region are counteracted by optimizing the distances of a plurality (up to n) of vacuum seals in the transition region.

[0095] An apparatus for bonding a first substrate surface of a first substrate to a second substrate surface of a second substrate comprises a first receiving device for receiving the first substrate and a second receiving device for receiving the second substrate, wherein a holding surface of the receiving device alternately comprises vacuum areas with fixing elements and transition areas therebetween without fixing elements and without vacuum supply.

[0096] The substrate holder can also have sensors, by means of which physical and / or chemical properties between the fixed substrate and the receiving device can be measured and can be used in a control loop to control the fixation, in particular the vacuum value.

[0097] In particular, reference is also made to the device from the printed document WO 2017 / 162272 A1. Therefore, further device features are not described in detail here.

[0098] In addition, a method for bonding a first substrate surface of a first substrate to a second substrate surface of a second substrate by means of a device is also provided. In particular, reference is also made to the already disclosed method steps from the printed document WO 2017 / 162272A1.

[0099] In a first process step of the first process, a first substrate is loaded and fixed on a first receiving device, and a second substrate is loaded and fixed on a second receiving device.

[0100] In the second process step of the first process, the two substrates are aligned with each other. The alignment of the substrates is not described in detail here. In this regard, reference is made to printed documents WO2015 / 082020A1 and WO2014 / 202106A1.

[0101] In a third process step of the first process, the two substrates are brought closer together by moving the two substrate holders relative to one another.

[0102] In the fourth process step of the first process, bending of the first substrate and / or the second substrate is performed.

[0103] In the fifth process step of the first process, substrate bonding is performed after contact at the bonding start point, and monitoring and control of the bonding wave are performed.

[0104] The alignment and bonding in the alignment device and / or bonding device are preferably performed under normal pressure. The substrate is fixed to the receiving device by vacuum or negative pressure.

[0105] The vacuum is preferably maintained between 5 mbar and 950 mbar negative pressure. Here, the vacuum is maintained as the fixing force of the fixing element. In vacuum fixing, the pressure is especially between 0.01 mbar and 1000 mbar, preferably between 0.01 mbar and 800 mbar, more preferably between 0.01 mbar and 500 mbar, most preferably between 0.01 mbar and 100 mbar, most preferably between 0.01 mbar and 50 mbar. The pressure difference between the larger external pressure and the smaller internal pressure in the vacuum fixing element is the pressing pressure on the substrate, which leads to the fixing of the substrate. BRIEF DESCRIPTION OF THE DRAWINGS

[0106] Further advantages, features and details of the present invention are obtained from the following description of preferred embodiments and with reference to the accompanying drawings. In which:

[0107] Figure 1 shows a top view of a vacuum substrate holder according to a first embodiment of the present invention,

[0108] Figure 2 shows a top view of a vacuum substrate holder according to a second embodiment of the present invention,

[0109] Figure 3 shows a top view of a vacuum substrate holder according to a third embodiment of the present invention,

[0110] Figure 4a The first embodiment of the present invention has a transition zone. Figure 3 A cross-sectional view of the holding surface of the vacuum substrate holder,

[0111] Figure 4b shows a cross-sectional view of a holding surface of a vacuum substrate holder with a transition zone in a second embodiment according to the invention,

[0112] Figure 4cshows a cross-sectional view of a holding surface of a vacuum substrate holder with a transition zone in a third embodiment according to the invention,

[0113] Figure 4d shows a cross-sectional view of a holding surface of a vacuum substrate holder with a transition zone in a fourth embodiment according to the invention,

[0114] Figure 4e shows a cross-sectional view of a holding surface of a vacuum substrate holder with a transition zone in a fifth embodiment according to the invention,

[0115] Figure 4f shows a detail of a cross-sectional view of a holding surface of a vacuum substrate holder with a fixed substrate and with a transition zone according to a sixth embodiment of the invention,

[0116] Figure 4g The seventh embodiment of the present invention has a transition zone. Figure 3 Cross-sectional view of the holding surface of the vacuum substrate holder.

[0117] In the figures, identical components or components having the same function are denoted by the same reference numerals. The figures show a simplified, not necessarily true-to-scale, illustration of a receiving device having a vacuum region with fastening elements and a transition region without fastening elements. DETAILED DESCRIPTION

[0118] Figure 1 A top view of a receiving device according to the invention or a vacuum substrate holder according to the invention is shown in a first embodiment.

[0119] In the embodiment shown, the vacuum regions 5 , 5 ′, 5 ″ and the transition regions 6 , 6 ′, 6 ″ are arranged in annular, in particular circular, shapes.

[0120] according to Figure 1 The receiving device 1 has a holding surface with a plurality of fixing elements, in particular vacuum fixing elements 4 , 4 ′, 4 ″. The fixing elements 4 , 4 ′, 4 ″ can be designed in different ways. The outermost fixing element 4 is in particular designed completely circumferentially and circularly. The inner fixing elements are arranged symmetrically with respect to the center of the receiving device 1 .

[0121] The fixing element 4 , 4 ″ is designed in particular as a thin recess which can be evacuated preferably via the fluid opening 7 and thus serves as a vacuum fixing element.

[0122] Figure 1 The fixing elements 4, 4', 4" define vacuum regions 5, 5', 5", respectively. Figure 1 The vacuum regions 5 , 5 ′, 5 ″ are shown, which are arranged symmetrically with respect to the center of the receiving device 1 .

[0123] The vacuum zones 5 , 5 ′, 5 ″ are separated by transition zones 6 , 6 ′, 6 ″. The transition zones 6 , 6 ′, 6 ″ each separate two different vacuum zones and are not supplied with a vacuum. Therefore, they do not have their own fixing elements.

[0124] The transition zone between two vacuum zones realizes a gradual vacuum transition from the first vacuum zone to the second vacuum zone. The transition zone 6' is, for example, located between the vacuum zone 5' and the vacuum zone 5".

[0125] The distance between two vacuum zones is in particular less than 50 mm, preferably less than 25 mm, even more preferably less than 20 mm, most preferably less than 15 mm, most preferably less than 10 mm. Figure 1 If the components are designed as circle segments, the distance is the distance between the inner circle of the outer circle segment and the outer circle of the inner circle segment.

[0126] The number of fixing elements per vacuum zone is arbitrary. In particular, there is at least 1 fixing element, preferably at least 2 fixing elements, preferably more than 10 fixing elements, more preferably more than 20 fixing elements, even more preferably more than 50 fixing elements, and most preferably more than 100 fixing elements in one vacuum zone. Figure 1 In the example, there is a fixed element in a vacuum region.

[0127] A plurality of vacuum zones arranged in succession can be controlled, in particular activated or deactivated, so that the local fixation of the substrate can be adjusted. In particular, the vacuum zone is activated by switching on all fixing elements in the vacuum zone.

[0128] The receiving device 1 can also have different sensors 8, in particular pressure measuring sensors and / or distance sensors. In the base body 2 of the receiving device 1 there are measuring holes 3 on the holding surface for measuring process parameters from the back side of the substrate.

[0129] A deformation element, in particular a pin or a nozzle, can be located in the center of the substrate holder 1 as a curvature-changing means.

[0130] Figure 2 A simplified top view of a receiving device 1 ′ is shown, wherein vacuum regions 5 , 5 ′, 5 ″, 5 ′″ and transition regions 6 , 6 ′, 6 ″, 6 ′″ therebetween are arranged in a plurality of rings, preferably circular rings, around the center of the receiving device 1 ′.

[0131] The simplified fastening elements 4 , 4 ′, 4 ″, 4 ′″ are each evacuated via their own, individually controllable fluid openings 7 . In a particularly preferred embodiment, the fastening elements 4 , 4 ′, 4 ″, 4 ′″ are set back, in particular milled, relative to the substrate holder surface.

[0132] If a loading pin (not shown) is used, it is provided with a seal, for example.

[0133] according to Figure 2 The receiving device 1 ' has a mainly transparent measuring aperture 3 so that measurements can be performed from the back side of the substrate to monitor process parameters. Preferably, at least the upper substrate holder has a measuring aperture. The measuring aperture can be designed in particular to be closable and / or sealed.

[0134] A distance sensor 8 can be integrated into the receiving device 1 ′ in order to measure the distance between the holding surface and the loaded substrate at any given point in time.

[0135] Figure 3 A top view of a receiving device 1 ″ in a third embodiment is shown.

[0136] The fastening elements 4 , 4 ′, 4 ″ are evacuated via their own lines or fluid openings 7 and in particular the recessed, preferably milled, recess in which the nub 9 is located.

[0137] Figure 3 The fixing elements 4, 4', 4" define vacuum zones 5, 5', 5", respectively.

[0138] Figure 3 The vacuum regions 5 , 5 ′, 5 ″ are shown, which are arranged symmetrically with respect to the center of the receiving device 1 .

[0139] The vacuum zones 5, 5', 5" are separated by transition zones 6, 6'. The transition zones 6, 6' respectively separate two different vacuum zones and are not actively supplied with vacuum. The transition zone 6 achieves a gradual vacuum transition between the vacuum zone 5 and the vacuum zone 5'. Similarly, the transition zone 6' achieves a gradual vacuum transition between the vacuum zone 5' and the vacuum zone 5".

[0140] Figure 3 An enlarged section of the transition region 6 is shown. The vacuum region and the transition region are each separated by a vacuum seal. The surface of the transition region 6 can be structured. The structure 10 can be, for example, a further vacuum seal which is lowered from the height of the holding surface of the substrate. The vacuum regions 5, 5' with the fixing elements 4, 4' are each evacuated via separate fluid openings 7 and are structured as a block surface. The fixing of the substrate is achieved by evacuating the space between the blocks. Figures 4a to 4f Different embodiments of transition zone(s) are shown and explained in more detail in .

[0141] In accordance with Figure 3 In the receiving device 1", multiple vacuum areas, especially multiple vacuum areas arranged side by side, can be grouped and switched together. In this way, larger surfaces can be advantageously switched as needed, so that the bonding process and separation from the receiving device 1" can be more flexible and more precise.

[0142] The optimal number of vacuum zones per circumferential portion and the optimal number of vacuum zones in the radial direction as well as the optimal design of the transition zones therebetween can be optimized, in particular, by empirical measurements and / or simulations.

[0143] In this case, the two substrates to be bonded to one another are fixed in such a way that factors influencing the formation and propagation of the bonding wave are reduced as much as possible, in particular by controllable fixing, in particular over large areas. By a gradual vacuum transition from one vacuum area to the next vacuum area in the holding surface of the receiving device, which is caused by a transition area that is not actively supplied with vacuum, distortions caused by bonding can be reduced, since abrupt changes in the framework conditions for the bonding wave are avoided.

[0144] Figure 4a A schematic, not to scale, cross-sectional view of a first embodiment of a holding surface of a receiving device is shown. The transition region 6 is located between two vacuum regions 5, 5'. The vacuum regions 5, 5' have a nodular structure with nodular blocks 9 of height H1 and are evacuated via fluid openings 7, 7'. The transition region 6 is not actively supplied with a vacuum.

[0145] The width or diameter of the receiving protuberances, in particular the nubs, is in particular less than 5 mm, preferably less than 2 mm, even more preferably less than 1 mm, most preferably less than 500 μm, most most preferably less than 200 μm. In a preferred embodiment, the width is between 100 μm and 2 mm.

[0146] The height of the receiving elevations, in particular the nubs, is in particular less than 2 mm, preferably less than 1 mm, even more preferably less than 500 μm, most preferably less than 200 μm.

[0147] In particular, the ratio between the width or diameter of the receiving protuberance and the height of the receiving protuberance is greater than 0.01, preferably greater than 1, even more preferably greater than 2, most preferably greater than 10, most most preferably greater than 20.

[0148] The vacuum regions 5, 5' with the fixing elements 4, 4' serve to fix the substrate (not shown). A vacuum seal separates the surface of the transition region 6 from the two vacuum regions 5, 5. Figure 4a The transition region 6 additionally shows two further structures, in particular vacuum seals. Between the two vacuum seals in the transition region 6 there is a gap 11 in each case.

[0149] The gradual vacuum transition from one vacuum region 5, 5' to the other vacuum region 5, 5' is determined by the height of the vacuum seal 10 between the two vacuum regions 5, 5' and the number and height of the structures in the transition region 6 located therebetween. Figure 4aThe embodiment of shows two further vacuum seals as structures 10. By designing the transition region 6, the flow resistance in the region of the vacuum seal 10, in the region of the transition region with the gap 11 and in the region of the vacuum regions 5, 5' is controlled in such a way that an equilibrium is produced between the two vacuum regions 5, 5' in the transition region 6, because the vacuum in the transition region 6 is balanced by the leakage at the vacuum seal and the structure 10.

[0150] The setback of the vacuum seal 10 relative to the support plane of the substrate on the holding surface of the receiving device defines the gap height h, which should achieve leakage. The vacuum seal can be set back, for example, between 100 nm and 5 μm, preferably between 100 nm and 3 μm, more preferably between 100 nm and 500 nm. In contrast, the height H1 of the block defining the height of the support surface of the substrate is, for example, between 100 μm and 1000 μm.

[0151] Figure 4b A second embodiment of the transition zone 6' is shown. In this embodiment, the vacuum seal 10' is also set back relative to the support plane of the substrate (height H1 of the nodule). Figure 4b , the gap 11' is filled to the height H2, so the volume of the gap 11' in the transition region 6' is small. Thus, the balance between the two vacuum regions 5, 5' can be controlled in the transition region 6'.

[0152] Figure 4c A third embodiment of a transition region 6 ″ is shown, which has an additional vacuum seal in the transition region 6 ″. Figure 4c The vacuum seal 10 ″ has a height H3 which is significantly smaller than the height H1 of the node for supporting the substrate. The vacuum regions 5 , 5 ′ are evacuated via the fluid openings 7 , 7 ′, while the transition region 6 ″ is not actively supplied with a vacuum.

[0153] In accordance with Figure 4dIn a fourth embodiment of the transition zone 6'', the vacuum seal 10'' between the vacuum zone 5, 5' and the transition zone 6'' or the vacuum seal 10'' in the transition zone 6'' between two vacuum zones 5, 5' is not set back relative to the surface of the substrate support. Instead, small channels 12 are added at regular intervals in the vacuum seal 10'' along the direction at multiple locations. Here, the cross-section of these channels 12 is selected so that it is significantly smaller than the cross-section in the area of ​​the block 9. The cross-section of the channel is less than 1 / 10, preferably less than 1 / 30, more preferably less than 1 / 50, even more preferably less than 1 / 80, most preferably less than 1 / 100, and most preferably less than 1 / 200 of the cross-section in the area of ​​the block 9. It is thus ensured that the pressure drop occurs mainly in the area of ​​the vacuum seal 10'' and that the vacuum is uniform in the area of ​​the vacuum zones 5, 5'. There is a gap 11'' between the two vacuum seals with the channels.

[0154] The leakage cross section or flow cross section of the sealing arrangement should be significantly smaller than the cross section of the supply line. The leakage cross section is in particular 1 / 2, preferably 1 / 5, more preferably 1 / 10, even more preferably 1 / 30, most preferably 1 / 50, most preferably 1 / 100 of the cross section of the supply line. This ensures that the leakage is the decisive resistance in the system and that the vacuum value in the region of the support surface (holding surface) can be controlled in a targeted and accurate manner.

[0155] The axial distance between the vacuum seals or vacuum structures 10'" is preferably between 0.5 mm and 50 mm, more preferably between 2 mm and 50 mm, even more preferably between 5 mm and 50 mm. The width of the vacuum structure is in particular between 0.5 μm and 1 mm, preferably between 1 μm and 750 μm, more preferably between 5 μm and 500 μm.

[0156] Figure 4e The transition zone 6 is shown IV A fifth embodiment in which the surface of the transition zone is largely filled and has only a height H4 which is less than the height H1 of the node or a line structure 10 with a gap height h IV Set back relative to the nodule face. The wire structure is arranged on a wide vacuum seal. The axial distance of the wire structure is uniform and in particular 1.5 μm. Preferably, the uniform axial distance of the wire structure is between 0.1 μm and 10 μm, even more preferably between 0.5 μm and 5 μm. The vacuum region 5, 5' with the nodule 9 is actively evacuated via the fluid openings 7, 7'.

[0157] Figure 4f A detail of a cross-sectional view of a holding surface of a substrate receiving device with a fixed substrate 13 having a transition region 6 is shown in a sixth embodiment. Figure 4fShown are a segment 9 with a height H, a gap height h of a setback vacuum seal and structure 10 and an axial distance t between the structures. The selection of H, h and t and the number of vacuum seals or structures in the transition region 6 allows for a design optimization of the transition region 6 .

[0158] By producing a gradual vacuum transition at the transition zone to compensate for the substrate fixation from one vacuum zone to another, the framework conditions for the bonding wave will also change gradually. This reduces and compensates for distortions, which leads to an improved quality of the bonded product.

[0159] Figure 4g The transition zone 6 is shown V A seventh embodiment having a transition zone 6 V Additional vacuum seal 10 V , similar to Figure 4c .according to Figure 4g , vacuum seal 10 V The vacuum seal 10 has a height H3 which is significantly smaller than the height H1 of the block for supporting the substrate. V The nodes 9 forming the support surface and carrying the substrate thereon are also located in the transition zone 6. V The vacuum zone 5, 5' is evacuated via the fluid openings 7, 7', while the transition zone 6 V No vacuum is actively supplied. For example, the vacuum seal or sealing structure can be moved back by between 100 nm and 5 μm, preferably between 100 nm and 3 μm, more preferably between 200 nm and 1 μm, and most preferably between 200 nm and 500 nm, compared to the receiving surface provided by the receiving ridge. Preferably, the axial distance of the block is between 1 mm and 8 mm, more preferably between 2 mm and 6 mm. The width or diameter of the receiving ridge, especially the block, is especially less than 5 mm, preferably less than 2 mm, more preferably less than 1 mm, most preferably less than 500 μm, and most preferably less than 200 μm. In a preferred embodiment, the width is between 100 μm and 2 mm. Sealing structure 10 V The width is smaller than the axial distance of the segment, and is in particular smaller than 5 mm, preferably smaller than 2 mm, more preferably smaller than or equal to 1 mm.

[0160] Reference numerals list

[0161] 1 Vacuum substrate holder, receiving device, substrate receiving device, substrate holder

[0162] 2 Matrix

[0163] 3 Measuring holes

[0164] 4,4',4",4"'Fixed elements

[0165] 5,5',5",5"' Vacuum area

[0166] 6,6',6”,6”',6 IV ,6 V Transition Zone

[0167] 7,7' fluid opening

[0168] 8 Sensors

[0169] 9 receiving ridges, nodes

[0170] 10,10',10",10"',10 IV ,10 V Sealing structure, structure, vacuum seal

[0171] 11,11',11",11"',11 V gap

[0172] 12 channels, open

[0173] 13 base

[0174] H,H1,H2,H3,H4Height

[0175] h Gap height

[0176] t Axial distance of the sealing structure

Claims

1. A vacuum substrate holder (1) for fixing a substrate (13), comprising: a) a first vacuum zone (5, 5', 5", 5'"') having at least one first fixing element (4, 4', 4", 4'"'), b) a second vacuum zone (5, 5', 5", 5'"') having at least one second fixing element (4, 4', 4", 4'"'), c) a receiving ridge (9) which is arranged at least in the first vacuum region (5, 5', 5", 5'") and at least in the second vacuum region (5, 5', 5", 5'"), wherein: The substrate (13) is arranged in a fixed state on a receiving surface provided by the receiving protuberance (9), and d) at least one transition region (6, 6', 6", 6"', 6"') separating the first vacuum region (5, 5', 5", 5"') from the second vacuum region (5, 5', 5", 5"') IV ,6 V ), Wherein, the transition zone (6,6',6",6"',6 IV ,6 V ) has at least one sealing structure (10, 10', 10", 10"', 10 IV ,10 V ), The invention is characterized in that, in a fixed state, the first vacuum area (5, 5', 5", 5"') and the second vacuum area (5, 5', 5", 5"') pass through the transition area (6, 6', 6", 6"', 6 IV ,6 V ) are fluidly connected to each other.

2. The vacuum substrate support (1) according to claim 1, wherein: The at least one sealing structure (10, 10', 10", 10'', 10 IV ,10 V ) has at least one opening, and the sealing structure (10, 10', 10", 10'', 10 IV ,10 V ) can be preset by means of the at least one opening.

3. The vacuum substrate support (1) according to at least one of the preceding claims, wherein: At least one transition zone (6,6',6",6',6 IV ,6 V ) respectively have at least two sealing structures (10, 10', 10", 10"', 10 IV ,10 V ), and the transition zone (6,6',6",6"',6 IV ,6 V ) in the at least one transition zone (6, 6', 6", 6'", 6 IV ,6 V ) of the sealing structures (10, 10', 10", 10"', 10 IV ,10 V ) between the gaps (11,11',11",11"',11 V ).

4. The vacuum substrate support (1) according to at least one of the preceding claims, wherein: The two sealing structures farthest from each other (10,10',10",10"',10 IV ,10 V ) have the same corresponding flow cross-sectional areas.

5. The vacuum substrate support (1) according to at least one of the preceding claims, wherein: The gap (11, 11', 11", 11"', 11 V ) has a flow cross-sectional area greater than that of the transition zone (6, 6', 6", 6"', 6 IV ,6 V ) sealing structure (10,10',10",10"',10 IV ,10 V ) of the flow cross-sectional area.

6. The vacuum substrate support (1) according to at least one of the preceding claims, wherein: The gap (11, 11', 11", 11"', 11 V ) is the flow cross-sectional area of ​​the transition zone (6, 6', 6", 6', 6 IV ,6 V ) sealing structure (10,10',10",10"',10 IV ,10 V )'s flow cross-sectional area is 5 times, preferably 10 times, more preferably 30 times, still more preferably 50 times, most preferably 100 times, and most preferably 200 times.

7. The vacuum substrate support (1) according to claim 1, wherein: The at least one sealing structure (10, 10', 10", 10'', 10 IV ,10 V ) has a uniform height (H1, H2, H3, H4) relative to the surface of the vacuum substrate support, and the at least one sealing structure (10, 10', 10", 10"', 10 IV ,10 V ) is smaller than the height (H) of the receiving protrusion (9) relative to the surface of the vacuum substrate support, so that in a fixed state, the at least one sealing structure (10, 10', 10", 10"', 10 IV ,10 V ) and the base (13) are provided with a gap having a gap height (h).

8. The vacuum substrate support (1) according to at least one of the preceding claims, wherein: The gap height (h) is less than 1 / 10, preferably less than 1 / 30, more preferably less than 1 / 50, still more preferably less than 1 / 80, most preferably less than 1 / 100, and most most preferably less than 1 / 200 of the height (H) of the receiving protuberance (9).

9. The vacuum substrate support (1) according to at least one of the preceding claims, wherein: The at least one sealing structure (10, 10', 10", 10'', 10 IV ,10 V ) at least partially abuts against the base (13) in a fixed state, and the channel (12) extends along the transition zone (6, 6', 6", 6'", 6 IV ,6 V ) is configured to be offset in the at least one sealing structure (10, 10', 10", 10"', 10 IV ,10 V )middle.

10. The vacuum substrate support (1) according to at least one of the preceding claims, wherein: The distance between at least one first vacuum zone (5, 5', 5", 5'") and at least one second vacuum zone (5, 5', 5", 5'") is less than 50 mm, preferably less than 25 mm, more preferably less than 20 mm, most preferably less than 15 mm, and most preferably less than 10 mm.

11. The vacuum substrate support (1) according to at least one of the preceding claims, wherein: At least one fixing element (4, 4', 4", 4'"') of the vacuum zone has at least one fluid opening (7, 7'), wherein the total flow area of ​​the respective vacuum zone (5, 5', 5", 5'"') is formed by all the fluid openings (7, 7') of the respective vacuum zone (5, 5', 5", 5'"'), and wherein the transition zone (6, 6', 6", 6'", 6'"') adjacent to the respective vacuum zone (5, 5', 5", 5'"') IV ,6 V ) sealing structure (10,10',10",10"',10 IV ,10 V ) is 1 / 2, preferably 1 / 5, more preferably 1 / 10, still more preferably 1 / 30, most preferably 1 / 50, and most preferably 1 / 100 of the total flow area of ​​the fixed elements (4, 4', 4", 4"') of the corresponding adjacent vacuum zones (5, 5', 5", 5"').

12. The vacuum substrate support (1) according to at least one of the preceding claims, wherein: The sealing structure (10, 10', 10", 10"', 10 IV ,10 V ) is directly connected to the transition zone (6, 6', 6", 6', 6 IV ,6 V ) is less than 1 / 10, preferably less than 1 / 30, more preferably less than 1 / 50, even more preferably less than 1 / 80, most preferably less than 1 / 100, and most preferably less than 1 / 200 of the total opening area between the receiving protrusions (9) of adjacent vacuum zones (5, 5', 5", 5'").

13. The vacuum substrate support (1) according to at least one of the preceding claims, wherein: The vacuum substrate support has a further vacuum region (5, 5', 5", 5"'), wherein the further vacuum region (5, 5', 5", 5"') is respectively formed by a further transition region (6, 6', 6", 6"', 6 IV ,6 V ) are separated, and wherein the vacuum zones (5, 5', 5", 5"') adjacent in the radial direction are respectively separated by the further transition zones (6, 6', 6", 6"', 6 IV ,6 V ) are fluidly connected to each other.

14. An apparatus for bonding substrates having at least one vacuum substrate holder (1) according to at least one of claims 1 to 13.

15. A method for bonding substrates, comprising the following steps, in particular in the following order: i) providing a first substrate (13) on a vacuum substrate support (1) according to at least one of claims 1 to 13, ii) providing a second substrate on a substrate support, iii) bonding the first substrate (13) to the second substrate.

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