Method and apparatus for aligning a substrate

Abstract

Apparatus and methods for aligning a substrate are presented.

Description

TECHNICAL FIELD

[0001] The present invention relates to a method and a device for aligning substrates according to the appended claims. BACKGROUND

[0002] The steadily progressing miniaturization in almost all parts of microelectronic and microsystem technology ensures a stable further development of all technologies by means of which the density of all types of functional units on a substrate can be increased. Microcontrollers, memory modules, MEMS, all types of sensors or microfluidic components, for example, belong to these functional units.

[0003] In recent years, the technologies for increasing the lateral density of these functional units have been greatly improved. In some subfields of microelectronic or microsystem technology, a further increase in the lateral density of the functional units is no longer possible to such an extent that in microchip production, the maximum achievable resolution limit of the structures to be produced in a lithographic manner has actually already been reached. Therefore, in a few years, physical or technical limits will completely no longer allow any increase in the lateral density of the functional units. For several years, the industry has been dealing with this problem by developing 2.5D and 3D technologies. By means of these technologies, the same or even different types of functional units can be aligned relative to one another, stacked on top of one another, permanently connected to one another and interconnected to one another by means of corresponding printed conductors.

[0004] One of the key technologies for implementing these structures is permanent bonding. Permanent bonding is understood to be all methods with which substrates can be connected to one another in such a way that a separation of the substrates is only possible with a high energy outlay and a consequent destruction of the substrates. Different types of permanent bonding are known to the person skilled in the art.

[0005] One of the most important methods of permanent bonding is fusion bonding, also known as direct bonding or molecular bonding. Fusion bonding is understood to be a process in which two substrates are permanently connected by the formation of covalent bonds. Fusion bonding is formed primarily on the surface of non-metallic inorganic materials. Fusion bonding can be carried out in a plurality of method steps: by means of so-called pre-bonding, pretreated clean substrates are connected to one another. In the pre-bonding method, the two substrates are bonded to one another by means of van der Waals forces alone. This bonding process primarily takes place between silicon substrates and / or silicon oxide substrates. The bonding process connects a first substrate surface of a first substrate to be bonded with a second substrate surface of a second substrate to be bonded. The bond energy of the weak bonds is sufficient to connect the substrates to one another in an immobile manner. However, the pre-bonding enables a non-destructive, in particular non-damaging, separation of the mutually bonded substrates. The pre-bonding is converted into an inseparable connection of the substrates only by means of a thermal treatment.

[0006] The clamping of the substrates aligned relative to each other can be carried out mechanically in full, as desired, first or after pre-bonding. In a particular embodiment, the substrates are clamped to each other, preferably using the method described in patent specification PCT / EP2013 / 056620. In this case, magnetically acting fixing means are used for the quick and simple fixing of the two substrates aligned relative to each other and in contact. The clamping can also be carried out in any other way. In particular, the substrates aligned relative to each other can be clamped to a sample holder.

[0007] The prior art knows innumerable methods for measuring alignment marks, which are used for the correct positioning of the substrates on which the alignment marks are located and for the subsequent bonding step. According to the prior art, the substrates are aligned relative to each other by means of an alignment device, in particular according to US6214692B1, WO2014202106A1 or WO2015082020A1. The alignment device of the publication US6214692B1 can be considered the closest prior art. In this alignment device, two optical device sets, each with two optical devices opposite each other, are used in order to create a system with two reference points, in which the substrates are positioned relative to each other. The reference points are the intersection points of the optical axes of the two optical devices opposite each other.

[0008] In a known device, an optical system and a rotation system are used for the positioning of substrates according to the principle of folding calibration (Umschlagsjustierung), for which see Hansen, Friedrich: Justierung, VEB Verlag Technik, 1964, paragraph 6.2.4, Umschlagmethode, bei welcher mindestens eine Messung in einer definierten Position und mindestens eine Messung in 180 Grad gedrehter, entgegengesetzt orientierter, umgeschlagener Position durchgeführt wird [folding method, in which at least one measurement is carried out in a defined position and at least one measurement is carried out in a rotated 180 degrees and oppositely oriented folded position]. The measurement results thus obtained are, inter alia, free of eccentricity errors.

[0009] One problem during the alignment of at least two substrates is that the movement process of the alignment should be carried out faster and yet more precisely, i.e. with a lower position residual uncertainty, so that the substrates are connected and joined to each other in the ideal position as far as possible. These movement requirements contradict each other.

[0010] Furthermore, parasitic movements and additional paths determined by the structure of the device itself should be eliminated as far as possible. Parasitic movements occur, inter alia, as an effect of vibrations, thermal influences, movement loads and as an interference effect of electromagnetic fields on the device. The structure-determined additional paths are the trajectory paths of the first substrate to be joined and the second substrate to be joined, which are cancelled by optimizing the device while preserving the alignment function of the device and, inter alia, by increasing the position accuracy.

[0011] In the case of the alignment devices in the prior art, the loading and unloading direction is mostly identical to the main movement direction of the alignment of the substrates. For the detection of the alignment marks, the two substrates travel several times through a length corresponding to the entire substrate diameter.

[0012] In this case, the design of the alignment device is based on the historical development of a manual alignment device with two binocular microscopes each, as disclosed in the publication US6214692B1. In this design, the ergonomic working position of the operator is taken into account and the two observation microscopes are positioned at the same distance to the operator on the normal to the main movement direction of the loading and unloading direction.

[0013] In WO2014202106A1, the loading and unloading direction is transverse to the main movement direction of the alignment of the substrates. For the detection of the alignment marks, a short travel path is possible. However, the positioning of the two binocular microscopes is essentially identical to the structure of the conventional alignment device.

[0014] PCT / EP2016 / 070289 uses additional alignment features of the substrate holder, which are combined with substrate features and enable a more precise alignment. The mechanical structure is essentially realized according to the conventional alignment device.

[0015] The essential problem of the prior art arises from the design of the current alignment devices. Any parasitic movement of the substrates and / or parts of the device to be aligned is detrimental to the alignment accuracy.

[0016] In particular, undesired movements are displacements of the relative position of the substrates with respect to each other, vibrations of the entire device and parts thereof, parasitic movements caused by moving loads (movement of the block on the guide rail causes a lateral displacement), undesired yaw, pitch or roll on the linear guide rails used. Furthermore, vibrations of the image acquisition elements should be minimized in order to avoid the need for refocusing. Generally, vibrations cause parasitic movements which cause disturbances in the time frame of a few microseconds to a few seconds.

[0017] Mechanical faults caused by thermo-mechanical conversion and / or thermal noise and / or thermal expansion lead to parasitic movements. The time intervals in which these mechanical faults occur are in the range of seconds to days. Therefore, the detection of the caused mechanical faults and the compensation are complex.

[0018] All listed parasitic movements are known to the person skilled in the art of mechanical engineering and mechatronics. In particular, if the parasitic movements constitute a system fault of the alignment, the parasitic movements influence the success of the alignment.

[0019] These system faults are objectively determined by the alignment device and the measurement method. For the devices in the prior art, the guiding of the substrates and the drive system as well as the image acquisition elements together with their positioning and drive system can be the source of faults.

[0020] The image acquisition elements of the devices of the prior art, in particular binocular microscopes which can acquire focal planes in opposite directions, are located at the end of an open console. Therefore, the fixation of the image acquisition device on a so-called open C-shaped design of a gantry is carried out. The open C-shaped design is increasingly prone to vibrations which can only be damped with considerable structural effort and cannot be eliminated in the low frequency range between 0.1 Hz and 1 Hz or 0.1 Hz and 10 Hz, mainly. SUMMARY

[0021] Therefore, it is the task of the present invention to specify a method and a device with which the precision of the alignment of the substrates with respect to each other can be improved and at the same time the speed of the alignment of the two substrates is increased. A more precise and more efficient alignment and contacting of the substrates is thereby achieved.

[0022] This task is solved with the features of the independent claims. Advantageous refinements of the invention are specified in the dependent claims. All combinations of at least two of the features specified in the description, claims and / or drawings also fall within the scope of the invention. In the case of value ranges, the values within the mentioned limits should also be disclosed as limit values and should be claimable in any combination.

[0023] According to the application, a method for aligning substrates is provided, wherein a detection of alignment marks is carried out and the substrates are aligned relative to each other in dependence on the detection of the alignment marks, wherein at least two alignment marks are arranged flush with a linear movement member of the substrates.

[0024] Furthermore, according to the application, a device for aligning substrates and for carrying out the method according to the application is provided, wherein a detection of alignment marks can be carried out and the substrates can be aligned relative to each other in dependence on the detection of the alignment marks, wherein at least two alignment marks are arranged flush with a linear movement member of the substrates.

[0025] It is preferably provided that at least three alignment marks are arranged flush with a linear movement member of the substrates.

[0026] It is preferably provided that at least one alignment mark is arranged at or on a substrate holder.

[0027] It is preferably provided that at least two alignment marks are arranged at the substrates and at least one alignment mark is arranged at the substrate holder, wherein the alignment marks are arranged flush with a linear movement member of the substrates.

[0028] It is preferably provided that the detection unit for detecting the alignment marks is arranged in at least one ring portal, preferably in at least one fully enclosed ring portal.

[0029] It is preferably provided that the detection unit for detecting the alignment marks is arranged in two ring portals, preferably in two fully enclosed ring portals.

[0030] It is preferably provided that the detection unit for detecting the alignment marks is arranged in a ring portal, preferably in a fully enclosed ring portal and in a C-column.

[0031] It is preferably provided that the alignment is carried out along a unique alignment axis, wherein the alignment axis extends parallel to the loading and unloading direction of the substrates.

[0032] In other words, the core of the application is that at least two alignment marks are arranged flush with a linear movement member of the substrates. In this case, two alignment marks can for example be located on the substrate, or for example one alignment mark can be located on the substrate and the other alignment mark can be located on the substrate holder. However, for example two or more alignment marks can also be located on the substrate and / or on the substrate holder. These exemplary configurations apply not only to the first / upper substrate or the first / upper substrate holder but also to the second / lower substrate or the second / lower substrate holder. According to the application, at least two alignment marks are arranged flush with a linear movement member of the substrates. Thereby, due to the reduction of the lateral movement, a high alignment accuracy can be achieved.

[0033] The concept underlying the present application is, inter alia, to improve the alignment accuracy by means of an increased rigidity of the device with an entry design and / or by detecting at least three alignment marks (in the following also referred to as alignment marks), which are arranged flush with the linear movement of the substrate.

[0034] Preferably, at least one alignment mark is arranged at or on the substrate holder. The position detection of the substrate holder provides a correction value for the orientation and alignment state of the substrate to be aligned.

[0035] In an advantageous embodiment, the at least one substrate holder has a preferably flat mounting surface for the substrate.

[0036] Furthermore, the at least one substrate holder can inter alia comprise prismatic bodies which are connected to the mounting surface monolithically, which can be used as reference surfaces for an optical position measurement, inter alia, in the case of a known geometry. These functional surfaces are configured as laser reflectors, so that by means of the knowledge of the point of incidence of the laser and the geometry, the exact orientation of the body in space can be determined. In this case, the orientation of the functional surfaces can be measured by means of an interferometer and corrected accordingly in a closed control loop.

[0037] The device for aligning at least two substrates according to the present application has at least one optical system with two optical devices or detection units, which are inter alia aligned opposite each other, the optical paths of which meet preferably in a common focal point. The common focal point constitutes a point of the idealized joining plane of the first substrate and the second substrate. The substrates join each other in this plane. The exact description and calibration of the focal point are described in detail in the publication WO2014202106.

[0038] According to an advantageous embodiment, the optical system or the detection unit comprises beam shaping and / or deflection elements, such as mirrors, lenses, prisms, radiation sources, inter alia for a Kohler illumination, and image acquisition means, such as a camera (CMOS sensor or CCD, or area or line or point detection means, such as phototransistors), and movement means for focusing and analysis means for adjusting the optical system.

[0039] The improved solution of the device according to the present application comprises more than two identical optical systems with aligned optical devices.

[0040] Furthermore, the device according to the present application comprises a substrate holder for mounting the substrates to be aligned. An embodiment of the device according to the present application comprises at least two movable substrate holders, which can mount and fix the first substrate to be aligned and the second substrate to be aligned. The movement and positioning system of the substrate holders is subsumed as movable substrate holder.

[0041] The substrate can have any arbitrary shape, but is preferably circular. A wafer is always understood to be a substrate. In particular, the diameter of the substrate is standardized in industry. For wafers, the industry standard diameters 1 inch, 2 inches, 3 inches, 4 inches, 5 inches, 6 inches, 8 inches, 12 inches and 18 inches or the corresponding metric conversions apply. However, the device according to the application can in principle process any substrate, regardless of its diameter.

[0042] According to the application, it is conceivable to use, instead of a substrate, a stack of substrates composed of at least two substrates connected to one another and to connect the stack of substrates to a substrate or to another stack of substrates. In the further disclosure, the stack of substrates can be used and understood in the sense of being subsumed under the substrate.

[0043] The alignment of the substrates relative to one another takes place in particular in accordance with alignment markings located on the contact faces of the substrates. The alignment markings on the opposite sides of the relative substrates are in particular complementary to one another.

[0044] The alignment markings can be any objects that can be aligned relative to one another, such as a cross, a square or a circle, and similar propeller shapes or grid structures, in particular for the phase grid of the spatial frequency range.

[0045] The alignment markings are preferably detected by means of electromagnetic radiation of a defined wavelength or wavelength range, in particular infrared radiation, visible light or ultraviolet radiation. However, the use of radiation of other wavelength ranges is likewise possible.

[0046] Furthermore, the device according to the application can comprise a system for producing prebonds.

[0047] Furthermore, the device according to the application preferably comprises a movement device with a drive system, a guide system, fastening and a measuring system in order to be able to move, position and align the optical system and the substrate holder and / or the substrates relative to one another. The movement device can perform an adjusted positioning of the substrate holder, which is handled by a control and / or regulation unit, in particular a computer and / or a regulation algorithm.

[0048] The movement device can generate any movement as a result of a plurality of individual movements, so that the movement device can preferably comprise a fast, coarse positioning device that does not meet the accuracy requirements and a fine positioning device that works precisely. The nominal value of the position to be traveled to is the ideal value. The movement device approaches the ideal value. The defined environment around the ideal value can be understood as the nominal value being reached.

[0049] A positioning device is understood to be a coarse positioning device if the positioning or repeatability accuracy deviates from the nominal value by less than 0.1%, preferably less than 0.05%, particularly preferably less than 0.01% relative to the total travel path or rotational range (360 degrees of full rotation in the case of a swivelable rotary drive). For example, in the case of a coarse positioner (English: pre-aligner) with a travel path of more than 600 mm (double substrate diameter), a positioning accuracy of 600 mm * 0.01%, i.e. less than 60 micrometers, thus results as a residual uncertainty. In other embodiments of the coarse positioning, the residual uncertainty of the positioning or repeatability accuracy is less than 200 micrometers, preferably less than 150 micrometers, particularly preferably less than 50 micrometers. In this case, thermal interference variables should likewise be taken into account.

[0050] A coarse positioning device fulfils the positioning task with sufficient accuracy only if the deviation between the actually reached actual position and the nominal value of the position lies within the travel range of the assigned fine positioning device.

[0051] An alternative coarse positioning device fulfils the positioning task with sufficient accuracy only if the deviation between the actually reached actual position and the nominal value of the position lies within half the travel range of the assigned fine positioning device.

[0052] A positioning device is understood to be a fine positioning device if the positioning and / or repeatability accuracy has a residual uncertainty of less than 500 ppb, preferably less than 100 ppb, in the ideal case 1 ppb relative to the nominal value relative to the total travel path or rotational range. Preferably, the fine positioning device according to the application will have an absolute positioning error of less than 5 micrometers, preferably less than 1 micrometer, particularly preferably less than 100 nm, quite particularly preferably less than 10 nm, in the optimal case less than 5 nm, in the ideal case less than 1 nm.

[0053] The alignment and possibly the contact (fusion bonding) take place by means of precision drives, such as piezoelectric drives.

[0054] The device according to the application and the associated method preferably have at least two positioning devices of the highest accuracy and reproducibility. The concept of mutual error correction can be used for the quality of the alignment of the substrates. Thus, a known offset (twist and / or displacement) of one substrate and the corresponding positioning device can be compensated using an adjustment and correction of the position of the other positioning device and the other substrate with a correction value or correction vector. In this case, it is a matter of the size and type of the twist and / or displacement to control or regulate how the error correction is carried out using coarse and fine positioning or only coarse positioning or only fine positioning. In other texts, positioning devices (coarse or fine or composite positioning devices) and alignment members are used in such a way that they are considered synonymous.

[0055] According to the application, the alignment of the substrates relative to each other can be carried out in all six degrees of freedom of movement: three translations according to the Cartesian coordinate directions x, y and z and three rotations around these coordinate directions. The x, y and z directions or x, y and z positions are understood to be directions or arranged positions extending in a Cartesian x-y-z coordinate system. The x and y directions correspond in particular to the lateral directions of the substrates.

[0056] From the position and / or orientation values of the alignment marks of the substrates and from the alignment marks on the substrate holders, position features are derived / calculated. According to the application, the movement can be carried out in any direction and orientation. Preferably according to the disclosure in publication EP 2612109 B1, the alignment of the substrates comprises in particular passive or active wedge error compensation.

[0057] The method according to the application improves the alignment accuracy in particular by means of additional X-Y position and / or orientation information which is detected with an additionally arranged detection unit and / or measurement and regulation system and is used for the control / regulation of the alignment. The additionally arranged detection unit and / or measurement and regulation system can be a further optical set of two mutually opposed optical devices.

[0058] In a preferred embodiment, an additional, in particular third, alignment mark is arranged on the substrate holder. This additional position feature is detected with at least one additional measurement system with a novel additional optical path. The alignment marks on the substrate holder are likewise arranged flush with the linear movement elements of the substrates. The position detection of the substrate holder provides correction values for the orientation and alignment state of the substrates to be aligned. By correlation of the additional measurement value and at least one of the measurement values of the other detection units, the alignment accuracy is improved. By correlation of at least one of the measured alignment marks in the joint interface between the contact surfaces and the alignment marks on the substrate holder which are also visible during the alignment of the substrates, direct observability of the alignment marks and thus real-time measurement and regulation during the alignment are achieved.

[0059] In a preferred embodiment, the additional measurement system is a laser interferometer. The laser interferometer allows control of the linear movement of the substrate holder by measuring position changes (measurement of displacement), changes in the tilt angle (measurement of angle), flatness (measurement of displacement and angle), orthogonality (measurement of angle) and, if necessary, dynamics (measurement of speed). In particular, the measurement of the change in the tilt angle allows detection of the tilt of the slide on the linear guide. The measurement of straightness allows detection or precise detection of horizontal or vertical deviations of the slide on the linear guide. For highly accurate laser interferometric measurements, real-time correction of the laser wavelength is necessary depending on the medium. In this case, for example, pressure, material temperature and / or gas temperature, if present, must be detected.

[0060] A particularly preferred embodiment has at least one laser interferometer per substrate holder and / or substrate, preferably two laser interferometers per substrate holder and / or substrate, which detect the X-Y position and / or alignment orientation and / or angular position of the two substrate holders and / or substrates relative to a defined reference, in particular relative to the frame. Preferably, the at least one interferometer is fixed to the frame.

[0061] Robots for substrate processing are subsumed under mobile devices. Fasteners can be integrated in components and / or functionally integrated in the mobile device. Furthermore, the device according to the application preferably comprises a regulation system and / or an analysis system, in particular a computer, in order to carry out the described steps, in particular the movement sequences, to carry out corrections, to analyze and store the operating states of the respective device according to the application. The method is preferably created as a recipe and executed in machine-readable form. A recipe is a set of optimized values of parameters which are in a functional or method-technical correlation. The use of a recipe allows to ensure the reproducibility of the production sequence.

[0062] Furthermore, according to a preferred embodiment, the device according to the application comprises supply and auxiliary and / or complementary systems, such as compressed air, vacuum, electrical energy, liquids (such as hydraulic, coolant, heating medium), means and / or devices for temperature stabilization, electromagnetic shielding.

[0063] Furthermore, the device according to the application preferably comprises a frame, a cover, active or passive subsystems which suppress or attenuate or eliminate vibrations.

[0064] In a preferred embodiment of the device, the detection unit, preferably together with its movement unit, can be arranged in at least one ring-shaped measuring inlet, particularly preferably in at least one fully enclosed ring-shaped measuring inlet, in particular in a manner fixed to the frame.

[0065] A preferred embodiment of the device with a unique inlet is further referred to as a single-inlet implementation. The single inlet enables a travel through the substrate together with the substrate holder, so that detection of at least the alignment mark of the substrate is enabled. In continuation, the position of the substrate holder can likewise be detected together.

[0066] The core idea of the present application is in particular to enable a reduction of the alignment to only one unique alignment axis, while increasing the alignment accuracy of at least two substrates. The layout of the device in a closed design increases the rigidity of the device, reduces the vibration capability and enables the detection of at least two, more preferably three, alignment marks which are arranged flush with the linear movement of the substrates.

[0067] Since the alignment axis is in particular congruent with the loading and unloading direction, additional movements transverse to the loading and unloading direction are cancelled. By the combination and correlation with directly detectable alignment marks on the substrate holder, the alignment accuracy is additionally improved.

[0068] In a preferred embodiment of the device, the at least two detection units can be arranged on the main longitudinal axis of the device. In a further preferred embodiment of the device, the at least two detection units can be arranged as an upper detection unit and a lower detection unit with a preferably common focal point.

[0069] In a preferred embodiment of the device, the upper detection unit and the lower detection unit with independent movement units can be connected with the frame or with the inlet, so that, inter alia, focusing and calibration methods can be carried out with which, inter alia, the common focal point can be readjusted.

[0070] In a preferred embodiment of the device, the movement units of the detection units can be moved in the global, inter alia, frame-fixed coordinate system in the main coordinate directions x, y, z. The movement path of the movement units of the detection units is less than 20 mm, preferably less than 10 mm, particularly preferably less than 5 mm in the plane of the substrate, i.e. in the x and y directions.

[0071] In a preferred embodiment, the movement units of the detection units can be moved, inter alia, in the z direction, by more than 5 mm, preferably by more than 10 mm, particularly preferably by more than 20 mm, so that focusing of non-standardized substrate stacks can also be achieved.

[0072] In an alternative embodiment, the height of the substrate can be compensated by the positioning of the substrate holder, so that a focusing path of less than 1 mm, preferably less than 0.5 mm, is used.

[0073] In a preferred embodiment of the device, the movement units of the detection units can be designed, inter alia, as gap-free solid joints or guide rails.

[0074] In another embodiment, all types of further detection means can be arranged, inter alia, in a frame-fixed manner in the inlet.

[0075] Furthermore, the device according to the application comprises at least one measuring system, preferably with a measuring unit for each movement axis, which can be implemented, inter alia, as a distance measuring system and / or an angle measuring system.

[0076] Tactile, i.e. touch or non-tactile measuring methods can be used. Measuring standards (measuring units) can exist as physical objects, inter alia, as scales, or implicitly in the measuring method, such as the wavelength of the radiation used.

[0077] In order to achieve the alignment accuracy, at least one measuring system can be selected and used. The measuring system implements a measuring method.

[0078] Inter alia, the following can be used

[0079] • inductive methods, and / or

[0080] • capacitive methods, and / or

[0081] • resistive methods, and / or

[0082] • comparison methods, in particular optical image recognition methods, and / or

[0083] • incremental or absolute methods (in particular with a glass scale as a scale, or an interferometer, in particular a laser interferometer, or with a magnetic standard), and / or

[0084] • time-of-flight measurements (Doppler method, time-of-flight method) or other time detection methods, and / or

[0085] • triangulation methods, in particular laser triangulation, and / or

[0086] • autofocusing methods, and / or

[0087] • intensity measurement methods, such as fiber-optic distance meters.

[0088] Furthermore, preferably according to PCT / EP2016 / 070289, a preferred embodiment comprises at least one additional measurement system, which detects the X-Y position and / or the aligned orientation and / or the angular position of one of the at least one substrate and / or one of the substrate holders relative to a defined reference, in particular relative to the frame.

[0089] A particularly preferred embodiment comprises an additional measurement system for all substrate holders, which detects the X-Y position and / or the aligned orientation and / or the angular position of the two substrate holders and / or the substrates relative to a defined reference, in particular relative to the frame.

[0090] A part, in particular a natural stone or mineral casting or spheroidal graphite cast iron or fluidly bonded concrete, which can be understood as a frame, which is in particular erected in an active or passive vibration-damping and / or vibration-isolating manner and / or with vibration removal. The frame can comprise a further holding and / or guiding function. In particular, lines for compressed air can be accommodated in the frame volume in the interior of the frame. Furthermore, electrical lines and connections can be accommodated in the frame volume. Furthermore, fastening elements and / or anchoring points for superstructures can be connected in the frame, in particular in a form-fit and / or material-fit manner.

[0091] In a particularly preferred embodiment, the frame can be produced in a prototype method, in particular a filled negative. In a particularly preferred embodiment, the frame can comprise a core during filling.

[0092] In a particularly preferred embodiment, the frame can comprise a flatness standard. In a particularly preferred embodiment of the frame, the flatness standard can be molded such that the flatness standard can be copied multiple times.

[0093] According to the application, the measurement values can be combined with one another and / or referred to one another and / or correlated, such that by measuring the alignment marks, conclusions can be drawn about the position of a further alignment mark related to this alignment mark.

[0094] According to the application, the measurement values can be correlated with one another such that the relative positions of the alignment marks relative to one another exist as values, respectively, which allow a reference frame.

[0095] In a preferred embodiment according to the application, the position of the substrate holder is measured, in particular continuously, during the passage along the three coordinate axes through the entry, such that the actual guideways of the substrate are detected. The actual guideways are taken into account as correction factors when calculating the alignment position of the substrates relative to one another.

[0096] In a further preferred embodiment according to the application, the position of the substrate holder is detected at a point (or site or measurement point or field of view) relative to a reference, in particular a first alignment mark on the first substrate and / or a second alignment mark on the second substrate.

[0097] In a further preferred embodiment according to the application, the position of the substrate holder is detected at exactly two points relative to a reference.

[0098] In a further embodiment according to the application, the position of the substrate holder is detected at exactly three points relative to a reference and thus the position and orientation of the substrate holder are determined.

[0099] For the position determination at one point or two points or three points or any number of points, preferably optical pattern recognition by means of a camera system and a pattern arranged on the substrate holder can be used. The pattern is detected in real time during the alignment, in particular continuously.

[0100] In a further preferred embodiment, the position determination of the substrate holder can be carried out by means of a laser interferometer. Laser interferometry enables extremely accurate non-contact length measurements by means of interference. Laser interferometers allow the control of the linear movement of the substrate holder by measuring position changes (measurement of displacement), tilt angle changes (angle measurement), flatness (measurement of displacement and angle), orthogonality (angle measurement) and dynamics (measurement of speed in the case of a multi-beam interferometer).

[0101] In particular, the measurement of the tilt angle change allows the detection of the tilting of the slide on the linear guideway. The measurement of the straightness allows the detection or precise detection of horizontal or vertical deviations of the slide on the linear guideway.

[0102] The relative movement of the subsystems (individual interferometers to the frame and the measurement object, in particular the substrate holder) can thus be determined. For displacement measurements, a dual-frequency laser method can be used, for example. In this case, a measurement resolution of up to 5 nm, more preferably up to 1 nm, can be achieved at maximum travel speeds of up to 1 m / s (by application of multiple reflections). Dual-frequency lasers are likewise used for angle measurements.

[0103] Another possibility arises by using a plurality of parallel-mounted single-frequency laser interferometers. Here, the displacement is determined at a plurality of points of the substrate holder. In this case, a measurement resolution of up to 0.1 nm can be achieved. The angle change can be determined from the difference in the displacement of the measurement beams from one another and the difference in the displacement that occurs.

[0104] If an interferometer with three measurement beams (three-beam interferometer) is used, the angular position of the substrate holder and its displacement are determined in two axes. In a preferred embodiment of the device according to the application, a three-beam interferometer is used.

[0105] If required, additional angle measurements for the position determination of the substrate holder can be carried out with an autocollimator.

[0106] If a combined measurement system is used, the measurement values of the absolute incremental displacement sensors can be correlated with the measurement values of at least one interferometer and used in a mutually complementary manner. The accuracy of the absolute positioning can thus be improved.

[0107] The measurement methods listed can likewise be used for the position determination.

[0108] According to the application, it is also conceivable to reverse the arrangement, in particular by arranging the detection unit on the substrate holder and the alignment mark on the frame.

[0109] In order that the detection, analysis and control (and / or regulation) can be carried out at any point in time, in particular permanently, in particular continuously (and / or digitally in a time-discrete manner at a sufficiently high clock frequency), the control unit and / or the regulation unit is supplied with measurement values.

[0110] The alignment marks on the substrate can be detected, for example, by means of optical image recognition and / or pattern recognition. In particular, the orientation and / or alignment state of the associated substrate holder and all associated regulation parameters can be detected at the same time and stored in a matrix and further processed.

[0111] In a preferred embodiment of the apparatus, the position of the substrate holder can be measured with at least one interferometer beam, preferably with at least two interferometer beams, in the best case with at least three interferometer beams. At the same time, the position values of the substrate holder can be measured by an incremental encoder. Reference is made to these position values and the increase in the path measured from a given position. By the combination of the relative values of the interferometer and the readings of the incremental displacement sensor, the position values of the frame can be referenced to a neutral plane and / or a neutral position.

[0112] For the x-y position determination at least one point, in another embodiment according to the application, at least one interferometer can be used with a correspondingly configured (in particular monolithic) reflector for detecting the x-y position and / or orientation determination of the substrate holder. For this purpose, three interferometer beams can be used.

[0113] The number of interferometer beams can in particular correspond to the number of reflecting surfaces of the reflector. However, according to the application, it is also conceivable to use an extended reflecting surface, in particular a monolithic optical mirror, as a reflector with a plurality of interferometer beams.

[0114] The substrate holder, in particular formed from a monolithic block, preferably has at least two of the following functions:

[0115] • substrate fixation by means of vacuum (vacuum track, connection),

[0116] • shape compensation for deforming the substrate by means of mechanical and / or hydraulic and / or piezoelectric and / or pyroelectric and / or electrothermal operating elements, preferably according to the embodiments of EP2656378B1, WO2014191033A1 and WO2019057286A1.

[0117] • position and / or orientation determination (measuring standard, reflecting surface and / or prism (in particular reflector for interferometric measurement), registration mark and / or registration mark field, planarly configured measuring standard for planar measurement, volumetric standard (in particular in situ)).

[0118] • movement (guide rail).

[0119] The movement device according to the application, which is not only used for fine adjustment, is in particular configured as a robot system, preferably with an incremental displacement sensor. The accuracy of these movement devices for assisted movement is decoupled from the accuracy for aligning the substrate stack, so that the assisted movement is performed with a low repeatability accuracy of less than 1 mm, preferably less than 500 micrometers, particularly preferably less than 150 micrometers.

[0120] The control and / or adjustment of the moving devices for (transversal) alignment (fine adjustment) according to the application is carried out, inter alia, on the basis of the x-y position and / or alignment orientation detected with the further measuring means. The precision of these moving devices is preferably less than 200 nm, further preferably less than 100 nm, particularly preferably less than 50 nm, quite particularly preferably less than 20 nm, further preferably less than 10 nm, in the ideal case less than 1 nm.

[0121] Device with two measuring inlets

[0122] In another embodiment according to the application, the detection unit, inter alia, together with its moving unit, is integrated in two fully enclosed inlets which are connected to one another in a rigid, torsion-resistant manner.

[0123] Here, this embodiment also detects the alignment marks, inter alia, using a free optical path from the light source to the alignment marks, similar to WO2014202106A1.

[0124] The device has two inlets which are rigidly connected to one another at a spacing greater than the diameter of the substrate. Similar to the embodiment of US6214692B1, which is referred to below as the SmartView Aligner (SVA), at least two oppositely placed optical detection means with a common focal plane are arranged in the inlets in an adjustable manner.

[0125] The first enclosed inlet with the detection means is positioned at the end of the travel path, which detects the alignment marks one after the other at the edge of the substrate. For this purpose, the substrate is loaded on the substrate holder in a manner rotated by 90 degrees compared to the SVA, so that the alignment marks are arranged one after the other flush with the linear movement.

[0126] The upper substrate holder and the lower substrate holder each continue from the cover position of the substrate until the detection means and the edge with the alignment marks are exposed.

[0127] The second enclosed inlet enables a movement across the respective substrate holder, such as a loading or unloading movement.

[0128] Here, the substrate is likewise moved on a unique alignment axis in order to bring the alignment marks into the optical path of the second inlet.

[0129] The alignment of the substrates relative to one another is carried out, inter alia, indirectly from alignment marks located on the contact faces of the substrates. The alignment marks on the opposite sides of the substrates are inter alia complementary to one another.

[0130] In this embodiment, the alignment precision can also be increased by additionally carrying out or arranging the detection of additional, inter alia third, alignment marks on one of the substrates to be aligned or on the substrate holder.

[0131] The additional alignment marks are preferably arranged on the substrate holder. The position detection of the substrate holder provides correction values for the orientation and alignment state of the substrate to be aligned. By correlation of the additional measurement value and at least one of the measurement values of the other detection units, the alignment accuracy is increased. By correlation of at least one of the measured alignment marks in the joint interface between the contact faces and the alignment marks on the substrate holder, which are also visible during alignment of the substrate, direct observability of the alignment marks and thus real-time measurement and adjustment during alignment are achieved. In a preferred embodiment, the additional measurement system is a laser interferometer, preferably a three-beam interferometer.

[0132] In a preferred embodiment, the other detection means are arranged in the entry, in particular fixed to the frame. What is described above for the device applies to this embodiment.

[0133] Device with single entry and column

[0134] The further device according to the application has a single entry (as described previously) and a column (C-shaped design), which are rigidly connected to each other, in particular with a spacing greater than the diameter of the substrate.

[0135] Here, the detection units are integrated in the entry and in the column. Here, this embodiment also detects the alignment marks, in particular using a free optical path from the light source to the alignment marks, similar to WO2014202106A1.

[0136] The column with detection means is preferably positioned at the end of the travel path, which detects the alignment marks one after the other at the edge of the substrate. For this purpose, the substrate is loaded on the substrate holder in a manner rotated by 90 degrees compared to the SVA, so that the alignment marks are arranged one after the other flush with the linear movement.

[0137] The upper substrate holder and the lower substrate holder each continue to travel from the covered position of the substrate until reaching the detection means and exposing the edge with the alignment marks.

[0138] As described previously, the single entry enables a crosswise movement over the respective substrate holder, such as a loading or unloading movement.

[0139] Here, the substrate is likewise moved on a unique alignment axis in order to bring the alignment marks into the optical path of the single entry and the column.

[0140] The alignment of the substrates relative to each other is carried out, in particular indirectly, from the alignment marks located on the contact faces of the substrates. The alignment marks on the opposite sides of the substrates are in particular complementary to each other.

[0141] In this embodiment, the alignment accuracy can also be improved in that an additional, in particular third, alignment mark is detected, which is additionally applied or arranged on one of the substrates to be aligned or on the substrate holder.

[0142] The additional alignment mark is preferably arranged on the substrate holder. The position detection of the substrate holder provides a correction value for the orientation and alignment state of the substrates to be aligned. By correlation of the additional measurement value and at least one of the measurement values of the other detection units, the alignment accuracy is improved. By correlation of at least one of the measured alignment marks in the joint interface between the contact surfaces and an alignment mark on the substrate holder, which is also visible during the alignment of the substrates, direct observability of the alignment marks and thus real-time measurement and adjustment during the alignment are achieved. In a preferred embodiment, the additional measurement system is a laser interferometer, preferably a three-beam interferometer.

[0143] In a preferred embodiment, the other detection means are arranged in the single inlet and in the column, in particular fixed to the frame. What is set out above for the device applies to this embodiment.

[0144] Method

[0145] An exemplary embodiment of the method according to the application is explained by means of the single-inlet embodiment of the device. In this case, the substrates are loaded one after the other and pushed through the inlet with a scanning movement together with the substrate holder, so that the position of the respective alignment marks and the reference on the substrate holder are detected in a correlated manner.

[0146] The image-to-image alignment is carried out in accordance with the alignment marks of the substrates. The alignment accuracy is additionally checked in that the position of the substrate holder gives a statement about the position of the substrates by means of the additional alignment mark and the actual position of the substrate holder is taken into account by a correction factor.

[0147] A repeated embodiment of the method according to the application comprises the following steps, in particular at least partially sequential and / or simultaneous, in particular the following flow:

[0148] 1) Loading of the first / lower substrate with the support surface onto the first / lower substrate holder, wherein the alignment marks are arranged on the opposite sides (contact sides) parallel to the linear guide, i.e. flush with the linear movement of the substrate.

[0149] 2) Moving of the first / lower substrate together with the substrate holder into the field of view of the detection position of the first / upper detection unit of the optical system at the single inlet, in particular in the case of use of a movement device for coarse adjustment.

[0150] 3) In particular, the first / lower substrate holder is measured during the entire travel path, in particular by means of a three-beam interferometer. Displacement and angle give information about the position and tilt of the substrate holder on the linear guide, in particular.

[0151] 4) The first alignment mark is detected, in particular by means of pattern recognition.

[0152] 5) At the same time, the X-Y position and / or alignment position of the first substrate holder is detected by means of the additional measuring system according to the application (with a third detection unit), in particular by means of synchronization with the first detection unit. Displacement and angle give information about the orientation (position) and angle (tilt, i.e. pitch and yaw angle) of the substrate holder on the linear guide, in particular.

[0153] 6) The second alignment mark is detected, in particular by means of pattern recognition.

[0154] 7) At the same time, the X-Y position and pitch and yaw angle and / or alignment position of the first substrate holder is detected by means of the additional measuring system according to the application, in particular a three-beam interferometer (with a third detection unit), in particular by means of synchronization with the first detection unit.

[0155] 8) The first / lower substrate holder is moved out of the field of view of the optical system (light path for detection).

[0156] 9) The second / upper substrate is loaded onto the second / upper substrate holder. This method step can already be carried out before one of the preceding method steps.

[0157] 10) The second / upper substrate holder travels with the second / upper substrate into the field of view of the optical system at a single entry.

[0158] 11) In particular, the second / upper substrate holder is measured during the entire travel path, in particular by means of a three-beam interferometer. Displacement and angle give information about the position and tilt of the substrate holder on the linear guide, in particular.

[0159] 12) The second / lower detection unit of the optical system finds and detects the alignment mark on the second / upper substrate. In this case, the optical system is not mechanically moved, although a correction of the focus can be envisaged. Preferably, however, no focus movement is carried out.

[0160] 13) At the same time, the X-Y position and pitch and yaw angle and / or alignment position of the second substrate holder is detected by means of the additional measuring system according to the application, in particular a three-beam interferometer (with a third detection unit), in particular by means of synchronization with the second detection unit.

[0161] 14) The second alignment mark is detected, in particular by means of pattern recognition.

[0162] 15) At the same time, especially by synchronization with the second detection unit, the X-Y position and the pitch and yaw angle and / or the alignment position of the second substrate holder is detected by the additional measurement system according to the invention, especially a three-beam interferometer (with a third detection unit).

[0163] 16) Adjustment and analysis computer determines the alignment error, wherein the disclosure in the reference publications US6214692B1 (SmartView) and US9418882B2 (Enhanced Smart View) is referred to. Especially an alignment error vector is created from the alignment error. Subsequently, at least one correction vector is calculated. The correction vector can be a vector parallel and opposite to the alignment error vector, so that the sum of the alignment error vector and the correction vector is zero. In special cases, other parameters can be taken into account when calculating the correction vector, so that the result is different from zero.

[0164] 17) Alignment by means of fine positioning

[0165] 18) Correction of displacement / twist

[0166] 19) Optional method step: Bonding of the substrates. The bonding can also be a pre-bonding or a temporary bonding. With pre-bonding is meant a bonding connection which, after the pre-bonding step has been carried out, still allows the substrates (especially wafers) to be separated without irreparable damage to the surface.

[0167] 20) Unloading of the substrate stack from the device.

[0168] The loading sequence of the substrates can be arbitrary. Some method steps, like the loading of the substrates, can be carried out simultaneously. The additional measurement system can detect the position and / or the orientation of the upper substrate holder and the lower substrate holder and / or the upper substrate and the lower substrate.

[0169] The device according to the invention can also be operated in vacuum. Thus, the device can be used in a vacuum cluster or a high-vacuum cluster.

[0170] All technically possible combinations and / or permutations of the functions and / or material parts of the device and / or at least one of the method steps or methods which occur as a consequence are considered to be disclosed.

[0171] As soon as device features are disclosed in the current and / or in the immediately following description of the figures, these device features are also to be considered as disclosed as method features and vice versa. BRIEF DESCRIPTION OF DRAWINGS

[0172] Further advantages, features and details of the invention result from the following description of preferred embodiments and from the drawings. Said drawings:

[0173] In Figure 1Fig. 1 shows a schematic cross-sectional view of a first embodiment of a device according to the application,

[0174] In Figure 2 Fig. 2 shows a schematic cross-sectional view of a second embodiment of a device according to the application,

[0175] In Figure 3a Fig. 3 shows a schematic enlarged cross-sectional view of a first embodiment according to the application in a first method step, Figure 1 Fig. 4 shows a schematic enlarged cross-sectional view of a first embodiment according to the application in a second method step, and Figure 3b Fig. 5 shows a schematic perspective view of an exemplary embodiment of a device according to the application. Figure 1 Figure 4 In the figures, identical components or components having the same function are marked with the same reference numerals. DETAILED DESCRIPTION

[0176] In

[0177] In Figures 1 to 4 In the figures, the ratios of the individual components are not to scale. In Figures 1 to 4 Fig. 3, the features according to the application are not shown to scale in order to be able to better illustrate the function of the individual features.

[0178] Figure 1 and Figure 2 Fig. 1 shows a schematic cross-sectional view of two embodiments of a device 1, 1' according to the application. These devices have:

[0179] - a first / upper detection unit 2, 2' in the form of first / upper optics,

[0180] - a second / lower detection unit 3, 3' in the form of second / lower optics,

[0181] - a third detection unit 4 in the form of a three-beam interferometer,

[0182] - a first / lower support in the form of a lower substrate holder 6 or having a lower substrate holder 6,

[0183] - a second / upper support in the form of an upper substrate holder 5 or having an upper substrate holder 5,

[0184] - a first / lower movement device 8 for the first / lower substrate holder 6,

[0185] - a second / upper movement device 7 for the second / upper substrate holder 5, and

[0186] - a third movement device 9 for the third detection unit 4.

[0187] According to​Figure 1 and Figure 2 The apparatus 1, 1' according to Figure 1 and Figure 2 is able to align and / or connect the substrates 14 (first / lower substrate) and 20 (second / upper substrate) and / or the substrate stack not shown in

[0188] Figures 1 to 4 The possible movements / freedom degrees of the functional components described below in the Figure 1 and Figure 2 first / lower pedestal 6 and the second / upper pedestal 5 are partly symbolically shown as arrows. For the first / lower pedestal 6 and the second / upper pedestal 5 according to

[0189] The φ-rotation unit allows the loaded substrate 14, 20 to be rotated around its surface normal. The resolution of the reproducible positioning ability of all used rotation units is especially better than 1°, preferably better than 0.1°, more preferably better than 0.01°, most preferably better than 0.001°, most preferably better than 0.0001°.

[0190] The resolution of the reproducible positioning ability of all used translation units is especially better than 100 pm, preferably better than 10 pm, more preferably better than 1 pm, most preferably better than 100 nm, most preferably better than 1 nm.

[0191] In embodiments according to Figure 1 the first and second detection units 2, 3 are not movable in all three spatial directions X, Y and Z. The detection units 2, 3 are statically mounted in the measurement inlet 21.

[0192] In embodiments according to Figure 2 the first and second detection units 2', 3' are movable in all three spatial directions. In another embodiment, a rotation unit can also be installed, which allows the optical axis to be rotated around three mutually orthogonal axes.

[0193] The first and second detection units 2, 2', 3, 3' according to Figure 1 and Figure 2 can detect the focal plane 10 in opposite directions. The common focal point 10p according to Figure 4 constitutes a point of the idealized joining plane of the first substrate and the second substrate.

[0194] According to Figure 1 and Figure 2The device 1, 1' provides a means for additional detection of the movement of the substrate, in particular by means of length measurement, pitch angle measurement and yaw angle measurement and straightness measurement by means of an additional third measuring device 4, said measurements being relative to at least one fixed, in particular stationary, reference point or reference and thus enabling the determination of a correction factor.

[0195] In a preferred embodiment, the additional detection of the movement of the substrate 14, 20 is carried out using a three-beam interferometer or a calibration laser interferometer 4. The measuring system 4 uses a novel additional optical path. For this purpose, in a preferred embodiment, an additional, in particular third, alignment mark 12 is preferably arranged on the substrate holder 5, 6. Using the interferometer 4, a simultaneous length measurement and pitch and yaw angle detection 17 is carried out according to Figure 3a and Figure 3b .

[0196] In another preferred embodiment, the additional third measuring device 4, in particular a laser interferometer, is stationary or fixed to the frame.

[0197] In another preferred embodiment of the device, the position of the substrate holder and / or the substrate can be measured using at least one laser interferometer fixed to the frame, preferably using two laser interferometers fixed to the frame.

[0198] The position detection of the substrate holder 5, 6 provides a correction value for the orientation and alignment state of the substrate 14, 20 to be aligned. By correlation of the additional measurement value and at least one of the measurement values of the other detection units 2, 2', 3, 3', the alignment accuracy is increased. By correlation of at least one of the measured alignment marks 15, 16 according to Figure 3a and Figure 3b and the alignment marks 12 on the substrate holder 5, 6, which are also visible during the alignment of the substrate, direct observability of the alignment marks 12 and thus real-time measurement and adjustment are achieved during the alignment according to Figure 3a In a first process step according to the application according to Figure 4 , the first / lower substrate holder 6 or the first / lower movement device 8 travels along a linear guide rail 18b for the first / lower movement device until the left or first alignment mark 15 of the first / lower substrate is located in the observation area of the upper measuring device 2 or the optics.

[0199] The movement of the translation unit and the rotation unit is detectable and transmits the detection data to a central control unit for further processing and control.

[0200] In a preferred embodiment according to Figure 3bIn a second process step according to the application, the first / lower substrate holder 6 or the first / lower moving device 8 is further advanced along the linear guide 18b (see Figure 4 ) for the first / lower moving device 8 until the right or second alignment mark 16 of the first / lower substrate 14 is located in the viewing area of the upper measuring device 2, i.e. the upper optical device.

[0201] In a third process step according to the application, which is not shown, the second / upper substrate holder 5 or the second / upper moving device 7 is advanced along the linear guide 18a (according to Figure 4 ) for the second / upper moving device 7 until the left or first alignment mark of the second / upper substrate 20 is located in the viewing area of the lower measuring device 3, i.e. the lower optical device.

[0202] In a fourth process step according to the application, which is not shown, the second / upper substrate holder 5 or the second / upper moving device 7 is further advanced along the linear guide 18a (see Figure 4 ) for the second / upper moving device 7 until the right or second alignment mark of the second / upper substrate 20 is located in the viewing area of the lower measuring device 3, i.e. the lower optical device.

[0203] According to the application, the optical devices are controlled, inter alia, such that the position of the alignment marks relative to the optical axis can be recognized, detected and stored by the optical devices.

[0204] The layout of the devices in the closed design increases the rigidity of the device 1, 1' and reduces the vibration capability. It is sufficient to align the guiding directions of the substrate holders 5, 6 relative to each other as precisely as possible. In this case, the three-beam interferometer 4 allows controlling the linear movement of the substrate holders 5, 6 by measuring the position change (measurement of displacement), the tilt angle change (measurement of angle), the flatness (measurement of displacement and angle), the orthogonality (measurement of angle) and the dynamics (measurement of speed).

[0205] In particular, the measurement of the tilt angle change allows detecting the tilt of the slide on the linear guide. The measurement of the straightness allows detecting or precisely detecting the horizontal or vertical deviation of the slide on the linear guide. The position features are derived or calculated from the position and / or orientation values of the alignment marks 15, 16 of the substrates 14, 20 and the alignment marks 12 on the substrate holders 5, 6 during the alignment of the substrates 14, 20.

[0206] The correlation of at least one of the measured alignment marks 15, 16 in the joint interface between the contact surfaces according to Figure 4 and Figure 3a and the alignment marks 12 on the substrate holders 5, 6, which are also visible during the alignment of the substrates 14, 20, enables a continuous direct correlation of the position data during the alignment and thus a real-time measurement and adjustment. Compared to conventional devices, the position correction increases the precision.

[0207] The control and / or adjustment of the movement means for the (transversal) alignment (fine adjustment) is carried out, inter alia, on the basis of the X-Y position and / or alignment orientation detected with the other measuring means. The precision of these movement means is preferably less than 200 nm, preferably less than 100 nm, particularly preferably less than 50 nm, quite particularly preferably less than 20 nm, further preferably less than 10 nm, in the ideal case less than 1 nm.

[0208] After all the necessary parameters have been determined, the alignment of the two substrates 14, 20 takes place in the last step.

[0209] The alignment of the substrates 14, 20 relative to one another is carried out, inter alia, indirectly from the alignment markings 15, 16 located on the contact faces of the substrates 14, 20.

[0210] The substrate holders 5, 6 are moved by means of the movement means 7, 8 in a position-adjusted and, in particular, orientation-adjusted manner until the alignment error calculated from the position values of the detection units (optics) and the current position and / or orientation of the substrate holders 5, 6 (three-beam interferometer) is minimized or, in the ideal case, eliminated. Alternatively, a termination criterion is defined.

[0211] Thereafter, finally, the contacting of the two substrates 14, 20 takes place preferably exclusively by means of the movement of the Z-translation unit(s) of the substrate supports 5, 6.

[0212] In one particular embodiment, the device 1, 1' can be located in a vacuum chamber or housing. The device 1, 1' can also be part of a cluster.

[0213] Figure 3b Schematic perspective view of embodiment 4. The first / upper detection unit 2 and, if necessary, further upper detection units and / or sensors and / or measuring units 2w are integrated in a single inlet 21. Similarly, the second / lower detection unit 3 and, if necessary, further lower detection units and / or sensors and / or measuring units 3w are also integrated in the single inlet 21 or frame 11.

[0214] Furthermore, embodiments according to Figure 4 have:

[0215] - a plurality of (fixed to the frame) detection units 4 for the lower and upper substrate holders 5, 6, respectively, in the form of three-beam interferometers,

[0216] - a first / lower support in the form of or having a substrate holder 6 for mounting the first / lower substrate 14 (in particular statically fixed) on the mounting side facing away from the side to be joined,

[0217] - a second / upper base plate holder 5 in the form of a substrate holder 5 or with an upper substrate holder 5 for mounting the second / upper base plate 20 (in particular statically fixed) on the mounting side facing away from the side to be joined,

[0218] - a first / lower moving device 8 for the first / lower base plate holder 6,

[0219] - a second / upper moving device 7 for the second / upper base plate holder 5.

[0220] Figure 4 Figure 4 Linear guides 18a for the second / upper moving device with fixed bearings 22 and guide elements 23 and linear guides 18b for the first / lower moving device are shown.

[0221] The first alignment mark 15 and the second alignment mark 16 of the first / lower base plate 14 are aligned substantially parallel to the main loading direction of the base plates 14, 20. This direction is given by the linear guides 18a and 18b. Precise drives 19 for correction movements around all three spatial axes are available to the base plates 14, 20.

[0222] List of reference signs

[0223] 1, 1'device

[0224] 2, 2' first / upper detection unit

[0225] 2w further upper detection unit and / or sensor and / or measuring unit

[0226] 3, 3' second / lower detection unit

[0227] 3w further lower detection unit and / or sensor and / or measuring unit

[0228] 4 third detection unit

[0229] 5 second / upper base plate holder

[0230] 6 first / lower base plate holder

[0231] 7 second / upper moving device for the base plate holder

[0232] 8 first / lower moving device for the base plate holder

[0233] 9 third moving device for the third detection unit

[0234] 10 theoretical focal plane

[0235] 10p theoretical focal point

[0236] 11 frame

[0237] 12 third alignment mark

[0238] 14 first / lower substrate

[0239] 15 first alignment mark of the first / lower substrate

[0240] 16 second alignment mark of the first / lower substrate

[0241] 17 simultaneous length measurement by the three-beam interferometer 4 and pitch and yaw angle detection

[0242] 18a linear guide for the second / upper moving device

[0243] 18b linear guide for the first / lower moving device

[0244] 19 precision drive

[0245] 20 second / upper substrate

[0246] 21 single inlet

[0247] 22 fixed bearing

[0248] 23 guiding element

Claims

1. A method for aligning substrates (14, 20), wherein - a detection of alignment marks (12, 15, 16) is carried out, and - the substrates (14, 20) are aligned relative to each other in accordance with the detection of the alignment marks (12, 15, 16), characterized in that at least two alignment marks (12, 15, 16) are arranged flush with linear movement elements (18a, 18b) of the substrates (14, 20), wherein the alignment takes place along a unique alignment axis, which extends parallel to the loading and unloading direction of the substrates (14, 20), wherein a detection unit (2, 2', 3, 3', 3w) for detecting the alignment marks (12, 15, 16) is arranged in at least one ring-shaped measuring portal (21).

2. The method according to claim 1, wherein at least three alignment marks are arranged flush with linear movement elements (18a, 18b) of the substrates (14, 20).

3. The method according to any one of the preceding claims, wherein at least one alignment mark (12, 15, 16) is arranged at or on a substrate holder (5, 6).

4. The method according to claim 1 or 2, wherein at least two alignment marks (15, 16) are arranged at a substrate (14, 20) and at least one alignment mark (12) is arranged at a substrate holder (5, 6), wherein the alignment marks (12, 15, 16) are arranged flush with linear movement elements (18a, 18b) of the substrates (14, 20).

5. The method according to claim 1 or 2, wherein a detection unit (2, 2', 3, 3', 3w) for detecting the alignment marks (12, 15, 16) is arranged in at least one fully enclosed ring-shaped measuring portal (21).

6. The method according to claim 1 or 2, wherein a detection unit (2, 2', 3, 3', 3w) for detecting the alignment marks (12, 15, 16) is arranged in two ring-shaped measuring portals (21).

7. The method according to claim 1 or 2, wherein a detection unit (2, 2', 3, 3', 3w) for detecting the alignment marks (12, 15, 16) is arranged in two fully enclosed ring-shaped measuring portals (21).

8. The method according to claim 1 or 2, wherein a detection unit (2, 2', 3, 3', 3w) for detecting the alignment marks (12, 15, 16) is arranged in a ring-shaped measuring portal (21) and in a C-shaped column.

9. The method according to claim 1 or 2, wherein a detection unit (2, 2', 3, 3', 3w) for detecting the alignment marks (12, 15, 16) is arranged in a fully enclosed ring-shaped measuring portal (21) and in a C-shaped column.

10. Apparatus (1, 1') for aligning substrates (14, 20) and for carrying out a method according to any one of the preceding claims, in which detection of alignment marks (12, 15, 16) can be carried out and the substrates (14, 20) can be aligned relative to one another in dependence on the detection of the alignment marks (12, 15, 16), characterized in that at least two alignment marks (12, 15, 16) are arranged flush with linear movement elements (18a, 18b) of the substrates (14, 20), wherein the alignment takes place along a unique alignment axis, which extends parallel to the loading and unloading direction of the substrates (14, 20).

11. The apparatus (1, 1') according to claim 10, wherein at least three alignment marks (12, 15, 16) are arranged flush with the linear movement of the substrate (14, 20) (18a, 18b).

12. The apparatus (1, 1') according to claim 10 or 11, wherein at least one alignment mark (12, 15, 16) is arranged at or on a substrate holder (5, 6).

13. The apparatus (1, 1') according to claim 10 or 11, wherein at least two alignment marks (15, 16) are arranged at a substrate (14, 20) and at least one alignment mark (12) is arranged at a substrate holder (5, 6), wherein the alignment marks (12, 15, 16) are arranged flush with the linear movement of the substrate (14, 20) (18a, 18b).

14. The apparatus (1, 1') according to claim 10 or 11, wherein a detection unit (2, 2', 3, 3', 3w) for detecting the alignment marks (12, 15, 16) is arranged in at least one fully enclosed ring-shaped measurement portal (21).

15. The apparatus (1, 1') according to claim 10 or 11, wherein a detection unit (2, 2', 3, 3', 3w) for detecting the alignment marks (12, 15, 16) is arranged in two ring-shaped measurement portals (21).

16. The apparatus (1, 1') according to claim 10 or 11, wherein a detection unit (2, 2', 3, 3', 3w) for detecting the alignment marks (12, 15, 16) is arranged in two fully enclosed ring-shaped measurement portals (21).

17. The apparatus (1, 1') according to claim 10 or 11, wherein a detection unit (2, 2', 3, 3', 3w) for detecting the alignment marks (12, 15, 16) is arranged in a ring-shaped measurement portal (21) and in a C-shaped column.

18. The apparatus (1, 1') according to claim 10 or 11, wherein a detection unit (2, 2', 3, 3', 3w) for detecting the alignment marks (12, 15, 16) is arranged in a fully enclosed ring-shaped measurement portal (21) and in a C-shaped column.

Images