DEVICE AND METHOD FOR ADJUSTING A RECORDING METHOD

Description

[0001] The present invention relates to a device and method for adjusting a detection means. The device and method are particularly suitable for adjusting detection means in alignment and processing equipment in the semiconductor industry.

[0002] In the semiconductor industry, alignment systems (aligners) are used to align substrates, especially wafers, with each other or with other components. Substrates can have any shape, but are preferably circular. The diameter of the substrates is standardized, particularly in industry. For wafers, the industry-standard diameters are 1 inch, 2 inches, 3 inches, 4 inches, 5 inches, 6 inches, 8 inches, 12 inches, and 18 inches.

[0003] The joining of aligned semiconductor substrates is called bonding. Precise alignment of the substrates is essential to avoid bonding defects and minimize the rejection rate. Furthermore, many applications require the highest possible accuracy. This is achieved by measuring alignment marks on the substrates or substrate holders relative to each other. Optical detection devices are used to detect the alignment marks and align the substrates.

[0004] For example, in bonding, the substrates to be bonded are aligned relative to each other and then joined together in a further process step. This always requires particularly precise alignment of the substrates. In the following text, bonding will preferably refer to fusion bonding. Alignment processes in which the alignment marks are located on the surfaces of the substrates to be bonded are called face-to-face alignments. Larger travel distances during alignment also result in larger alignment errors.

[0005] Another problem with the current state of the art is that increasing alignment accuracy requirements can no longer be met using simple methods. Methods in which substrates are measured relative to reference points and, for example, blindly aligned after an initial approach to contact, fail to meet these new alignment accuracy requirements.

[0006] For example, patent US6214692B1 is based on the comparison and position correction of two images of alignment marks. The position of the alignment marks on the two face-to-face arranged substrates is individually captured using a camera system. From a calculated relative position of the alignment marks, a positioning stage (substrate holder and stage) is controlled to correct the misalignment.

[0007] Further documentation US10692747B2 is based on the comparison and position correction of a total of three images of planar alignment marks. The position of alignment marks on the two face-to-face substrates is individually captured using a camera system. A third capture unit captures a third alignment mark, which is used to correlate an alignment mark on the substrate with the back of the substrate holder or with the back of the substrate, thus enabling more precise alignment of the two substrates.

[0008] Further devices and methods are known from publications EP3734650A1 and CN111354714A.

[0009] Therefore, visual inspection of two substrates when aligned face-to-face is not possible, or only possible if at least one of the substrates is at least partially transparent. Precise alignment of the surfaces when aligned face-to-face is thus only possible with difficulty and to a limited extent.

[0010] It has proven particularly disadvantageous that the optical detection elements of the individual alignment marks are positioned in an imprecisely defined location relative to the substrate holder and thus also to the substrate subsequently placed on the substrate holder. Due to the imprecise position of the detection elements, the detection of the individual alignment marks typically requires an adjustment movement in the lateral plane of the substrate holder and a focusing movement. Because of the controlled movements of the detection elements, the spatial position of the detection elements, especially optical detection elements such as measuring microscopes, is often so imprecise that accurate measurement and therefore sufficiently precise alignment of the substrate stack is not possible.

[0011] The adjustment movements, particularly of the optics used to detect the alignment marks, occur alongside the required movement, accompanied by superimposed, parasitic movements that cause deviations from the ideal movement of the respective optic. Thus, any movement can lead to a misalignment of the central axis of the detection elements, which in turn negatively affects the alignment accuracy.

[0012] It is therefore an object of the present invention to provide an improved device and an improved method for adjusting a sensing means, which eliminate at least some, and in particular completely eliminate, the disadvantages listed in the prior art. It is also an object of the present invention to provide an improved device and an improved method for adjusting a sensing means. Furthermore, it is an object of the present invention to provide a device and a method for adjusting a sensing means that takes into account the angular position relative to the substrate holder and is easy to implement. In particular, a further object of the present invention is to provide a method and a device for improved substrate alignment, which reliably, accurately, and simply determines and compensates for, i.e., adjusts, a wedge error between the substrate holder and the sensing means.

[0013] The present problem is solved by the features of the dependent claims. Advantageous embodiments of the invention are specified in the sub-claims. The scope of the invention also includes all combinations of at least two features specified in the description, the claims, and / or the drawings. Where specified value ranges are given, values ​​lying within the stated limits are also considered disclosed limits and may be claimed in any combination.

[0014] Accordingly, the invention relates to a device for adjusting a detection means, at least comprising: i) a substrate holder for receiving a substrate, ii) at least one adjustment marking field with adjustment marks fixed to the substrate holder, and iii) the detection means for detecting the adjustment marks, characterized in that the detection means is adjustable relative to the substrate holder by means of superimposed adjustment marks of the adjustment marking field, wherein the substrate holder has regularly arranged elevations on a substrate holder surface to provide a substrate receiving area and wherein several adjustment marking fields, each having adjustment marks, are regularly offset from one another between the elevations.

[0015] Furthermore, the invention relates to a method for adjusting a detection means comprising at least the following steps: i) Provision of a substrate holder with an adjustment marking field with adjustment marks fixed to the substrate holder and i) adjustment of the detection means relative to the substrate holder, characterized in that the detection means is adjusted on the basis of superimposed adjustment marks of the adjustment marking field, wherein the substrate holder has regularly arranged elevations on a substrate holder surface to provide a substrate receiving area and wherein several adjustment marking fields, each having adjustment marks, are regularly offset from one another between the elevations.

[0016] In other words, the sensing element is advantageously aligned using two alignment marks arranged at different heights within an alignment marking field. This particularly facilitates the compensation of a wedge error (angular error) between the sensing element and the substrate holder. Thus, any tilting of the sensing element can be adjusted and calibrated using a single alignment marking field with alignment marks arranged one above the other. In this document, the terms wedge error and angular error are used synonymously.

[0017] Since the detection device is preferably also designed to read alignment marks (on the substrate or on the substrate holder) during bonding, the alignment accuracy is thus increased by the prior adjustment. Furthermore, the substrate holder is designed to receive and provide a substrate as flat as possible. The alignment mark field is fixed relative to the substrate holder, so that the respective alignment marks also have a specific or known position with respect to the substrate holder. Preferably, the respective position of each alignment mark within the alignment mark field is known, so that after the detection device has detected two alignment marks arranged one above the other, alignment can be performed based on the detected alignment marks with their known positions.The detection element, or any parallel axis error, can be compensated for without relative movement parallel to the substrate holder (xy-axis) using the superimposed adjustment marks. After such an adjustment, the detection axis of the detection element is aligned perpendicular to the substrate holder, so that no tilting occurs and any angular error of the detection element can be eliminated by the device. Since any unknown angular error of a detection element can also cause an alignment error, the rejection rate during substrate processing is thus reduced.

[0018] For this purpose, the detection element is movable, in particular by a movement device, especially along a focal axis (perpendicular to the substrate holder in the z-direction). Furthermore, tilting or skewing of the detection unit can preferably be compensated for by particularly sensitive actuators. The determined wedge error between the detection unit and the substrate holder, or between the substrate holder and the substrate receiving surface of the substrate holder, can also be corrected by a compensating movement of the substrate holder.

[0019] The adjustment marks are markings attached to and / or in the substrate holder, which enable at least one adjustment of the detection means relative to the substrate holder. Preferably, several adjustment marking fields, each with its own adjustment marks in specific areas, are arranged distributed across the substrate holder, preferably aligned with the positions of subsequent alignment marks.

[0020] This allows the detection unit to advantageously detect adjustment marks of an adjustment marking field independently of the xy-position. Furthermore, a further movement to read the alignment marks is then possible without the detection means having to move in the xy-direction.

[0021] A particular advantage of the device and the adjustment method is that no reference wafer or other additional measuring system is required to align the scanning element and the substrate holder. This type of calibration can therefore be performed conveniently and frequently between individual processing steps. Another significant advantage of the device and the adjustment method is that multiple adjustment marking fields at different positions allow the scanning element to be precisely adjusted at the point of measurement. External influences, such as table deflection due to the weight of the optics, are thus taken into account and cannot subsequently cause misalignment of the scanning unit.

[0022] A substrate holder with at least one adjustment marking field can consist of several discrete components. Preferably, the substrate receiving surface is a reproducibly deformable plate, which is held in the substrate holder in a constrained manner. An adjustment marking field consists of at least one adjustment mark and another adjustment mark.

[0023] The adjustment marking field is fixed to the substrate holder or its surface. In particular, the exact position of the adjustment marking field and the respective positions of the adjustment marks within the field relative to the substrate holder are known. The adjustment marks, or at least two of them, are arranged one above the other.

[0024] In a preferred embodiment of the device, the adjustment marks of the adjustment marking field are arranged in a first plane and a second plane, with the first and second planes being parallel to each other and spaced apart. In other words, the adjustment marks of different planes have a known and constant distance from each other. In this way, adjustment can be carried out advantageously and precisely. Preferably, the planes of all adjustment marking fields are arranged identically with respect to the substrate holder. Based on the known distance, the wedge error between the sensing means and the substrate holder can thus be advantageously determined precisely, and in particular calculated.

[0025] In a further preferred embodiment of the device, the detection means is adjustable by a relative movement between the detection means and the substrate holder. In other words, after a first adjustment mark of a first plane has been detected, a second adjustment mark of a second plane of the adjustment marking field is detected by moving the substrate holder or the detection means in the z-direction. The length of the movement path can be compared with the distance between the planes of the adjustment marking field, and thus a skew or wedge error can be determined.

[0026] In a further preferred embodiment of the device, the sensing element is adjustable by changing its focus. In other words, the sensing element shifts its focus area to detect the respective other alignment mark. Advantageously, this focusing movement occurs without any relative movement of the sensing element or the substrate holder. Based on the focusing movement, e.g., of the optics, the distance between the alignment marks of different planes is measured and compared with the known distance. In this way, a particularly precise adjustment of the substrate holder to the sensing element is possible without errors resulting from relative movement. This refocusing of the sensing element allows lateral displacements to be detected and corrected accordingly if an apparent lateral offset of the alignment marks of two planes is detected during the focusing movement.Preferably, the substrate holder remains fixed in its position.

[0027] In a further preferred embodiment of the device, the alignment marks of the first plane and the alignment marks of the second plane are arranged in alignment with one another. In this case, the alignment mark field and the detection means are designed such that the detection of different aligned alignment marks is possible. For example, the alignment mark field is transparent to certain wavelengths.

[0028] In a further preferred embodiment of the device, the adjustment marks of the first level and the adjustment marks of the second level are arranged one above the other and regularly offset from each other. In this way, the adjustment marks can be advantageously easily detected by the detection unit.

[0029] In a further preferred embodiment of the device, the adjustment marks of the first level and the adjustment marks of the second level are arranged in a stepped, offset manner on different layers. In this way, no material of the adjustment marking field advantageously obscures the adjustment marks of different levels. Furthermore, several detection means can be selected.

[0030] In a further preferred embodiment of the device, each alignment mark additionally possesses individual information that can be detected by the detection device. In this way, the position of each detected alignment mark within the alignment mark field and / or in relation to the substrate holder is known. The known xy positions of the alignment marks, as well as their individual pattern (e.g., pixel) positions, are preferably known. Thus, the information content (e.g., provided as a barcode) can advantageously be included in the determination of the wedge error. This enables an even more precise and reliable determination of the wedge error. Furthermore, it allows for a subsequent relative determination of the substrate's position based on the alignment marks.

[0031] In a further preferred embodiment of the device, the detection means is an optical detection means, in particular an optic with a definable optical central axis. With optimal alignment, this central axis is exactly perpendicular to the substrate holder or the substrate holder surface and thus also to the alignment marks. By refocusing or changing the focus, the displacement of the focus area along the optical central axis can therefore be determined with particular precision.

[0032] In a further preferred embodiment of the device, the substrate holder has regularly arranged raised areas on its surface to provide a substrate receiving area, and several adjustment marking fields, each with adjustment marks, are arranged regularly offset from one another between the raised areas. The raised areas are preferably knobs or pins. In this way, the contact area between the substrate and the substrate holder, or the substrate receiving area, is advantageously small, so that contamination of the substrate surfaces can be minimized or prevented. The multiple adjustment marking fields arranged between the raised areas advantageously allow the wedge error to be determined at a multitude of positions. A relative movement of the detection element in the xy-direction, i.e., along the substrate holder surface, is therefore not required.Rather, in this way the wedge error can be determined advantageously and accurately, independent of position, by the measuring device, and the measuring device can be precisely aligned or adjusted.

[0033] In a further preferred embodiment of the device, the at least one adjustment marking field has a lower height relative to the substrate holder surface than the raised areas. The raised areas thus protrude relative to the adjustment marking fields with respect to the substrate holder surface. In this way, the substrate is advantageously not contaminated by the adjustment marking fields, since contact occurs only with the raised areas provided for this purpose.

[0034] In a further preferred embodiment of the device, one of the two planes of the at least one alignment marking field lies on the substrate holder surface. In other words, one plane of the alignment marking field is formed by the substrate holder surface. The alignment marks can be partially recessed into the substrate holder or arranged below the substrate holder surface. In this way, the alignment marking fields can be designed particularly simply and with less susceptibility to errors. Furthermore, the alignment marking fields can be integrated directly into the substrate holder.

[0035] In a further preferred embodiment of the device, the at least one alignment marking field is fully recessed into the substrate holder, which is located at least partially below the substrate holder surface. In other words, the planes are embossed into the substrate holder and have a negative height profile relative to the substrate holder surface. In this way, the alignment marking field can advantageously be embedded in the substrate holder and produced directly during manufacturing. Furthermore, the alignment marking fields are advantageously protected.

[0036] In a further preferred embodiment of the device, the sensing means is designed to read alignment marks on a substrate. The alignment marks are particularly preferably arranged in areas of the substrate holder surface that typically align with the positions of the alignment marks on the substrate or the substrate holder. In this way, the sensing means can advantageously align the alignment marks without having to perform a relative movement in the xy direction. Instead, the sensing means can advantageously remain stationary and perform the reading by means of a focusing movement or a shift of the focus area.

[0037] In one embodiment of the device, the device is encapsulated, so that at least the substrate holder and the detection means are installed in a system chamber that can be sealed gas-tight and / or vacuum-tight from the atmosphere. The corresponding auxiliary components include, for example, access points, airlocks, pumps, sensors, viewing windows, gas supplies, and temperature controls. In this embodiment, the system chamber can be filled with a special atmosphere, which is preferably free of water or water vapor. Furthermore, the special atmosphere can be free of oxygen. In another embodiment, the system chamber can be pressurized with a vacuum, preferably a high vacuum, and particularly preferably an ultra-high vacuum.The vacuum in the system chamber of this embodiment is less than 1*10E-3 mbar, preferably less than 1*10E-5 mbar, particularly preferably less than 1*10 -8 mbar, most preferably less than 5*10E-9 mbar, most preferably less than 1*10E-10 mbar, ideally less than 1*10E-12 mbar.

[0038] In a preferred embodiment of the method, the adjustment of the detection means in step ii) comprises the following steps with the following sequence: a) Detection of a first adjustment mark of a first level of the adjustment marking field, b) Detection of a second adjustment mark of a second level of the adjustment marking field, c) Determination of a wedge error between the detection means and the substrate holder, d) Compensation of the wedge error determined in step c), wherein the first plane and the second plane are arranged parallel to each other, and wherein the first plane and the second plane are spaced apart from each other.

[0039] This method allows for the adjustment of the detection device or the compensation of wedge errors, advantageously without a reference wafer or other additional measuring system. This type of calibration can be performed repeatedly between wafer bonding processes without requiring any movement of the detection device. Furthermore, the detection device can advantageously remain stationary and only perform a focus change or a shift in focus area to detect the alignment marks of different levels within an alignment marking field.

[0040] In a preferred embodiment of the device, the alignment marking field has further alignment marks in a third plane, which are preferably also arranged parallel to the other planes at a specific distance. Particularly preferably, the different alignment marks of different planes, offset in the z-plane, are transparent to different wavelengths, so that any further alignment mark in any plane of the alignment marking field can be detected by the detection means without obstruction.

[0041] By detecting one alignment mark and subsequently detecting another alignment mark positioned above it, the known positions and distances between the alignment marks can be compared with the measured value. Since the properties, structures, and positions of the alignment mark field are preferably known, the known distance between the alignment marks can be determined and used to correct optical detection devices. Based on this known distance, for example, an adjustment and / or correction of the detection device can be performed by moving the optical detection device relative to the stationary alignment mark field of the substrate holder, using the superimposed alignment marks, without requiring any movement of the substrate holder itself.In this way, an optical detection device can be aligned particularly precisely in at least one direction, since the known distance and spatial position between the superimposed adjustment marks is recorded and thus the actual position and angular orientation of the respective optical detection device can be calculated.

[0042] The relative positions of the various adjustment marking fields are preferably also known, so that the position of all adjustment marks on the substrate holder is known. The adjustment marking fields are preferably positioned on the substrate holder in the edge region of the substrate holder's surface, which is particularly round. In other words, the adjustment marking fields are clustered in specific regions, especially in areas where alignment marks are typically arranged in alignment during substrate processing. The adjustment marking fields are therefore preferably located on the substrate holder in spatially distributed positions at the points where the substrates to be aligned and the substrates to be joined contain the alignment marks.In this way, the position and spatial orientation of the respective optical detection device relative to the substrate holder can be calculated, and deviations from the ideal position can be used as correction values ​​for joining an upper substrate to the lower substrate.

[0043] The substrate holder preferably has a flat substrate contact surface. This substrate contact surface consists of a multitude of contact points and / or knobs, which are preferably evenly distributed.

[0044] In another embodiment of the substrate holder, the substrate support surface has an adjustable shape, which can be set depending on the specific substrate being attached. The position of the respective adjustment marks is still known.

[0045] Furthermore, the adjustment marking fields are set back from the substrate contact surface and preferably regularly offset between the contact points, so that the substrate does not come into contact with the adjustment markings.

[0046] In a particularly advantageous embodiment of the substrate holder, an adjustment mark and at least one further adjustment mark are located within the travel range of an optical detection element and a further optical detection element. This enables even more precise adjustment of the detection elements.

[0047] Adjusting the sensing element relative to the substrate holder serves to eliminate or at least reduce an error component that affects substrate alignment, particularly during fusion bonding, caused by positional and / or angular errors of the sensing element. By determining the alignment of the sensing element relative to the substrate holder and adjusting it accordingly, errors (parallax errors) can be reduced by orders of magnitude. Furthermore, correction values ​​are applied to the alignment of substrates to be joined in order to further minimize the alignment error between the substrates.

[0048] The superimposed alignment marks and the additional height information they provide allow for advantageous adjustment of the measuring device without requiring any additional movement of the substrate holder. This is because any movement of the substrate holder would introduce a parasitic movement that could ultimately increase the alignment error. The measured positions of one alignment mark and another (on a different plane) are compared with the actual, stored values. The height difference and the plane offset then allow for the determination of a positioning error, which can be corrected.

[0049] The adjustment marking field preferably contains several adjustment marks arranged side by side in the respective plane. This ensures that at least one first adjustment mark or at least one second adjustment mark of the corresponding plane is detected. Furthermore, the adjustment marking field between the planes is preferably transparent to the detection means, so that the superimposed adjustment marks can be detected. It is also conceivable that the adjustment marks of the first plane are offset from the adjustment marks of the second plane and that the adjustment marking field has different gradations.

[0050] Furthermore, the detection device can detect not only an adjustment mark of a specific plane, but also other adjustment marks of that plane, as long as they are located within the focus area. The same applies to other planes. Preferably, the detection device is designed such that multiple adjustment marks, especially adjacent adjustment marks of the respective plane, can be detected. This further increases the accuracy of determining the wedge error and allows for even more effective adjustment of the detection device.

[0051] In another embodiment of an adjustment marking field, the individual adjustment marks can be designed as 3D structures with defined corners and / or edges, wherein the individual position features are provided with a unique encoding (information content), so that a unique assignment of the corners and / or edges and / or steps to the 3D position information is enabled and a complete spatial mapping of the substrate holder with the adjustment marking field is made possible.

[0052] Preferably, an adjustment mark of the adjustment marking field is detected in a position where, in a further process, an alignment mark of a substrate is positioned. As a result of the positioning movements and adjustment and / or correction, neither the substrate holder nor the at least one detection means need to be moved or repositioned. The fixed positions increase the accuracy of the substrate alignment and subsequently of the bond.

[0053] The detection unit preferably has focusing means, preferably a lens, which focuses or sharpens the first alignment mark during detection. The detection unit or lens assumes a focus position in which it can detect a specific focus area. The focus area of ​​a specific focus position of the detection unit or lens is thus focused, and alignment marks arranged within this focus area can be detected. Preferably, only alignment marks of the respective plane can be detected or identified during detection, since a focus area of ​​the detection unit comprises exactly one plane. The distance between the first plane and the second plane is therefore preferably greater than the depth of the focus area, and more preferably at least twice as large or greater.

[0054] For focusing, liquid lenses with variable curvature and / or fast-switching, resonant liquid lenses can be used to simultaneously image multiple focal planes. It is also conceivable to change the refractive index of the lens to perform focusing and / or refocusing. The methods listed are equivalent to or superior to classical focusing and / or refocusing by changing the distances in the optical path.

[0055] Following the detection of the first alignment mark on the first level, the position of the detection element is fixed. This defines the focus area, ensuring that the detection unit can subsequently only detect alignment marks within this defined focus area. The second level is then detected by refocusing perpendicular to the first level of the alignment mark field on the substrate holder surface. The detection unit is moved at least until it can detect the second alignment mark on the second level of the alignment mark field. This focusing movement advantageously moves the detection unit by the distance required for focusing. This effectively prevents alignment errors resulting from a global repositioning of the detection unit and / or the fixed substrate holder.Due to the known topography and the unique and a priori known xyz positions of the individual adjustment marks in the adjustment marking fields on the substrate holder, the angular error of the detection unit at the measured adjustment marks can be calculated by the actual focusing movement and measurement.

[0056] For this purpose, the measured values, in particular the measured distance of the different planes of the adjustment marks as well as a lateral displacement and / or rotation, are compared with the stored ideal values, which are the approximations of the respective true values, and the difference is used as a correction value for further measurements.

[0057] If further adjustment marks are arranged in additional planes between the first and second planes, these can be measured by the detection unit during its focusing movement, thus enabling particularly precise and controlled movement of the detection unit. Furthermore, by detecting multiple adjustment marks whose positions within the adjustment marking field are known, the relative alignment and the determination of correction values ​​can be performed even more accurately.

[0058] The adjustment marks preferably contain information regarding their respective position within the adjustment marking field. In addition to their position along the adjustment marking field (xy-position), the respective height or distance between the planes is also known. Thus, when the first adjustment mark is detected, it can advantageously be determined in which plane it is located. Particularly when an adjustment marking field has more than two planes with different distances between them, alignment and focusing can be controlled or regulated more easily, since the respective height information regarding the adjustment mark is recorded. For example, with continuous detection during movement or when the first adjustment mark is detected, it is advantageous to determine which position in which plane or stage within the focus area is being recorded.Furthermore, if a position between two levels or steps is detected, it is advantageous to approach a level or step located above or below it. Additionally, the position in the xy-axis can be advantageously detected and monitored.

[0059] The device is preferably designed such that the focus position of the detection unit can be fixed immediately after detecting the first adjustment mark of the first plane of the adjustment marking field. The fixed focus position of the detection unit defines the sharply imaged focus area. In this way, the distance between the first plane and the second plane can advantageously be moved and thus focused by the movement device. The detection unit is also held stationary, particularly laterally, so that the distance between the planes can be determined simply by detecting the adjustment marks and moving the detection element in a z-direction. Direct visual inspection by exactly one detection unit can thus advantageously verify the correct alignment of the detection element with the substrate holder.

[0060] In one possible embodiment of the device for adjusting a sensing element, the at least one adjustment marking field is arranged on the rear side of the substrate holder, facing away from the substrate holder surface. The adjustment marking field can, for example, be attached to the rear side or recessed into the substrate holder. Alternatively, the adjustment marking field can also be formed by the substrate holder itself. Advantageously, the sensing unit can be arranged on the rear side facing away from the substrate holder surface.

[0061] In a preferred embodiment of the device for adjusting a sensing element, the center point of the adjustment marking field is at least partially aligned with the center point of the substrate holder surface. The central arrangement of the adjustment marking field advantageously allows for precise adjustment of the sensing element to the substrate holder. Furthermore, this embodiment advantageously enables the detection of linear error components or rotations of the sensing unit relative to the substrate holder.

[0062] Preferably, the adjustment marking field has at least three levels with adjustment marks. The information on which level the adjustment marks are located is provided on the adjustment marks. Furthermore, this allows the device to move to several specific distances, enabling the setting of multiple focus positions and thus defined distances between the detection element and the substrate holder during adjustment. The distances between the levels can be equal. Preferably, however, the levels are arranged at different distances from each other. This allows for flexible positioning of multiple distances. Setting different focus levels, and consequently setting specific, different relative distances between the detection element and the substrate holder, can be advantageous when working with substrates of varying thicknesses.

[0063] In a preferred embodiment of the device for adjusting a sensing means, the device comprises at least one further adjustment marking field and at least one further sensing unit for detecting the at least one further adjustment marking field, wherein the at least one further adjustment marking field is arranged in a fixed position relative to the substrate holder. The combination of several measured values ​​with respect to the further adjustment marking field allows for even more precise alignment, since detection takes place at multiple points. For example, displacements and / or rotational errors can be detected in this way. The adjustment marking field and the at least one further adjustment marking field are preferably arranged offset along the substrate holder.Particularly preferably, the device has a total of three adjustment marking fields and three detection units, each of which is distributed around a center point of the substrate holder surface, and is arranged in a radial direction uniformly offset from each other.

[0064] Alignment markers can be any mutually alignable objects such as crosses, circles, squares, propeller-like shapes, or grid structures, especially phase gratings for the spatial frequency domain. Furthermore, 3D objects such as pyramids, cones, and steps can be used as alignment markers.

[0065] In a particularly advantageous embodiment of the device, adjustment markings can at least partially include QR codes which describe, in particular, an absolute, machine-readable position encoding (x, y, z position) of the respective adjustment mark, so that a complete mapping of the substrate holder and / or the substrate holder surface with the adjustment marking fields is created before the substrate holder is used, in order to serve as reference values ​​for all adjustment operations.

[0066] In a further particularly advantageous embodiment, adjustment markings can include at least partially alphanumeric characters, which in particular describe an absolute, machine-readable position encoding (x, y, z position) of the respective adjustment mark. The alphanumeric characters can preferably also be read by the operator.

[0067] The alignment marks and / or alignment marking fields are preferably detected using electromagnetic radiation of specific wavelengths and / or wavelength ranges. These include, for example, infrared radiation, visible light, or ultraviolet radiation. The use of shorter wavelength radiation, such as EUV (extreme ultraviolet) radiation or X-rays, is also possible.

[0068] The adjustment marking field consists of, or thus includes, position-coded and height-coded adjustment markings, which provide unambiguous position and height information of the substrate holder for adjusting the detection means.

[0069] In one embodiment, the size or dimensioning of the adjustment marking field in the xy direction is adapted to the focus area of ​​the optical detection means, in particular, so that at least two levels or alignment marking planes can be considered.

[0070] The number of steps and the overall height of the adjustment marking field are preferably matched to the distance to be set. For example, if a focusing distance of at least 500 micrometers is to be set, 550 micrometers of height-coded position information are preferably displayed in the adjustment marking field to ensure that the distance can be unambiguously reached.

[0071] The acquisition is preferably carried out using suitable imaging optical systems, so that the imaging depth can be selected to be less than the step height or layer thickness of the alignment marking field. The imaging depth (depth of focus, DOF) is the area in the image space of an imaging optical system in which a sufficiently sharp image of a focused object, in particular an alignment mark or an adjustment mark, is produced. Conversely, this means that the image plane (an image acquisition device, sensor) can be moved within the imaging depth range without the image of an object becoming noticeably blurred.

[0072] If the detection of an adjustment mark of the adjustment marking field is carried out with a small imaging depth, which is smaller than the step height, preferably smaller than half the step height, particularly preferably smaller than 0.1 step height, the position of the adjustment marking field can be clearly determined, especially in the z-direction.

[0073] The imaging depth of the detection means is less than 50 micrometers, preferably less than 20 micrometers, particularly preferably less than 10 micrometers, most preferably less than 5 micrometers, and in the optimal case less than 4 micrometers.

[0074] However, if the image depth is sufficient to sharply image at least two step heights, the positioning uncertainty of the device is increased, because then a clear assignment of a z-height to a step cannot be made.

[0075] In a preferred embodiment of the device, an image capture element or a capture element of the capture unit can be reproducibly shifted by 0.2 step heights without refocusing the image. This can be used to determine which alignment mark of the adjustment mark field should be used for positioning when the image-side focus plane lies directly at the height of two adjacent steps and both steps appear equally sharp. A decision regarding the adjustment marks to be used can be made with this small shift of the image capture element (also as a computer-implemented, stand-alone method).

[0076] Due to physical limitations, only one plane or step is sharply imaged at a time when the adjustment marking field is captured. Therefore, preferably only one step or plane is within the focus area of ​​the detection unit. Since the adjustment markings of the adjustment marking field are position- and location-coded, position information, particularly of the substrate holder in a spatial coordinate system and / or of the detection device, can be determined from a sharply captured adjustment mark of a plane. By refocusing the detection device on another adjustment mark, the angular error of the detection device is determined from the known step height and the measured planar offset of the adjustment marks. This error can then be used as a correction value for aligning a substrate stack.

[0077] The adjustment procedure increases the alignment accuracy, in particular by providing correction values ​​for local angular errors of detection units, which are captured with further adjustment marking fields and corresponding further detection units and used to control and / or regulate the alignment.

[0078] For this purpose, the device for adjusting and aligning substrates and for bonding substrates preferably includes a control unit, in particular a software-based one, by means of which the steps described here are carried out and components are controlled. Closed control loops and control systems are to be understood as subsumed under the control unit.

[0079] The X and Y directions or X and Y positions refer to directions or positions within an XY coordinate system or within any Z-plane of the XY coordinate system. The Z direction is orthogonal to the XY directions. The X and Y directions correspond, in particular, to lateral directions, preferably along the planes of the adjustment marking field or along the substrate holder surface. The Z direction is preferably the direction in which the detection means is moved when the focus position of the detection unit is fixed in the XY plane.

[0080] Position characteristics are calculated or recorded from the position and / or location values ​​of the adjustment markings on the substrate holder, in particular by recording and evaluating the adjustment marking field.

[0081] The adjustment marking field is preferably located in close proximity to the alignment markings of the substrates. Particularly preferably, at least one alignment marking of the substrates and the adjustment marking field are arranged on the substrate holder in such a way that they can be detected without lateral repositioning of the detection element. An additional alignment marking field can also be arranged on the back of the substrate holder, which can be used both for adjusting an additional detection element and for aligning the substrate stack using correlated positions.

[0082] In a particularly preferred embodiment, at least one alignment marking field is located preferably in the z-direction aligned with the additional adjustment markings of the substrates, preferably on a back side of the substrate holder.

[0083] In a further preferred embodiment of the device, at least one adjustment marking field is located preferably in the z-direction aligned with the center of the substrate or with the center of the substrate holder surface, in particular on a back side of the substrate holder.

[0084] In a further preferred embodiment of the device, two adjustment marking fields are preferably aligned in the z-direction with the adjustment markings of the substrate holder, in particular on a rear side of the substrate holder.

[0085] In a further preferred embodiment of the device, at least one alignment marking field is located on the substrate side of the substrate holder or on the side of the substrate holder surface, near the substrate, in a position accessible for optical detection. These additional detection means can be aligned with the substrate holder in a first method and used as additional detection means for aligning substrates in a second method.

[0086] A further embodiment of the device includes at least two adjustment marking fields on the substrate side of the substrate holder near the substrate edge, for optical detection of the accessible position. This allows for advantageous leveling of the substrate holder.

[0087] The alignment method and the alignment device comprise, in particular, at least one additional detection unit with a corresponding measuring and / or control system and at least one additional adjustment marking field and / or alignment marking field, wherein the alignment accuracy is further increased by additional measured values ​​and correlations with at least one of the measured values ​​of the additional detection units. For this purpose, the respective correction values ​​from the measurements are applied.

[0088] In a further method, following the adjustment of the detection means when using corrections, the correlation of at least one of the measured additional alignment marks, particularly on the contact surfaces of a first substrate and / or second substrate, with at least one adjustment mark of the adjustment mark field, which is also freely accessible and visible during the alignment of the substrates, enables the direct observability of an adjustment mark and thus real-time measurement and control during alignment. This further increases the alignment accuracy of the substrates.

[0089] In a further embodiment of the device, at least one additional adjustment marking field is positioned on the substrate side of a substrate holder near the peripheral edge of the substrate in a position that is permanently accessible to a further detection unit. Preferably, one surface of the adjustment marking field is located in the same plane as the surface of the substrate attached to the substrate holder that is to be bonded.

[0090] The addition of 3D position markers on the substrate holder, which are clearly correlated with the position markers on the substrate, allows direct observation of the alignment marks on the substrate to be replaced by direct observation of the adjustment mark on the substrate holder. This has the advantage that the observable part of the substrate holder can practically always be positioned within the field of view or detection range of a detection unit. The 3D position information and the correction of the angular position of the detection elements enable the alignment of the substrates relative to each other to be performed with increased accuracy.

[0091] Preferably, the detection area of ​​a detection unit is smaller than 3 mm x 3 mm, more preferably smaller than 2 mm x 2 mm, and particularly preferably smaller than 1 mm x 1 mm.

[0092] Active feedback of data for positioning and position correction increases accuracy compared to state-of-the-art controlled positioning, since closed control loops provide a way to monitor the current position.

[0093] A correlation is established between the alignment marks of a first substrate and / or a second substrate on their respective contact surfaces and at least one adjustment mark of the adjustment mark field. This single adjustment mark of the adjustment mark field can be detected by the detection unit during alignment, particularly directly.

[0094] The direct detectability or observability of at least one additional adjustment mark in an additional adjustment marking field enables real-time measurement of the 3D position of the substrate holder or the detection means. The same device can be used for substrate alignment and bonding, particularly fusion bonding, to reduce alignment errors. This increases alignment accuracy because the detection of the adjustment marking field, along with the provision of correction values ​​and calculated height information, eliminates positioning uncertainties, thereby reducing error propagation. This measure improves alignment accuracy by reducing the number of necessary adjustment movements and providing controlled height adjustment during bonding.

[0095] The detection unit for detecting the adjustment marking field is in particular part of an optical system for detecting the adjustment marking field and, according to an advantageous embodiment, includes beam shaping and / or deflection elements such as mirrors, lenses, prisms, radiation sources, in particular for Köhler illumination, as well as image detection means such as cameras (CMOS sensors, or CCD, or area or line or point detection means such as a phototransistor) and movement means for focusing, as well as evaluation means for controlling the optical system.

[0096] In another embodiment of the device, the optical system can be used in combination with a rotation system for substrate positioning according to the principle of inversion adjustment (see Hansen, Friedrich: Adjustment, VEB Verlag Technik, 1964, Section 6.2.4, Inversion Method). Accordingly, in inversion adjustment, at least one measurement is performed in a defined position of the respective substrate holder and at least one measurement is performed in an inverted position rotated 180 degrees and oriented in the opposite direction. The measurement result obtained in this way is, in particular, corrected for eccentricity errors. Preferably, the substrate holder can be rotated, and the detection means remain fixed in position except for focusing.

[0097] A further development of the adjustment device can be used as a device for aligning substrates.

[0098] Furthermore, a device can include a system for producing pre-bonds. For this purpose, pressure pins and / or adjustable nozzles can be used to initiate the fusion bond for joining substrates. In particular, the adjustable nozzles can be height-adjustable, allowing the relative position to the back of the substrate to be changed and the nozzle flow rate to be controlled. Their alignment can advantageously be achieved using the superimposed adjustment markings.

[0099] Furthermore, a device preferably includes motion devices with drive systems, guide systems, holding devices and measuring systems to move, position and precisely align at least the detection unit and the substrate holder and thus the substrate to be aligned.

[0100] The motion devices can generate any movement as a result of individual movements, so the motion devices may preferably include fast, coarse positioning devices that do not meet the accuracy requirements, as well as precise fine positioning devices.

[0101] A positioning device is understood to be a coarse positioning device if the approach and / or repeatability deviates from the target value by more than 0.1%, preferably more than 0.05%, particularly preferably more than 0.01%, based on the entire travel distance or rotation range, or, in the case of recirculating rotary drives, a full revolution of 360 degrees.

[0102] For example, a coarse positioning device with a travel distance of over 600 mm (twice the substrate diameter) results in a approach accuracy of 600 mm * 0.01%, i.e., more than 60 micrometers as residual uncertainty.

[0103] In other embodiments of the coarse positioning system, the residual uncertainty of the approach or repeatability accuracy is less than 100 micrometers, preferably less than 50 micrometers, and particularly preferably less than 10 micrometers. Thermal disturbances are also taken into account.

[0104] A coarse positioning device only fulfills the positioning task with sufficient accuracy if the deviation between the actual position achieved and the target position lies within the travel range of an associated fine positioning device.

[0105] An alternative coarse positioning device only fulfills the positioning task with sufficient accuracy if the deviation between the actual achieved position and the target position is within half the travel range of an associated fine positioning device.

[0106] A positioning device is understood to be a fine positioning device if the residual uncertainty of the approach and / or repeatability accuracy from the target value does not exceed 500 ppb, preferably less than 100 ppb, more preferably 1 ppb, with respect to the entire travel distance or rotation range.

[0107] Preferably, a fine positioning device will compensate for an absolute positioning error of less than 5 micrometers, preferably less than 1 micrometer.

[0108] The substrates can be aligned relative to each other in all six degrees of freedom: three translations along the x, y, and z coordinate directions, and three rotations around these coordinate directions. These movements can be performed in any direction and orientation.

[0109] Robots used for substrate handling are classified as motion devices. The restraints can be integrated into the motion devices as components or integrated into their function.

[0110] Furthermore, the device for adjusting the detection unit preferably includes control systems and / or evaluation systems, in particular computers, to perform the described steps, in particular movement sequences, to make corrections, to analyze and store operating states of the device.

[0111] Processes are preferably created as recipes and executed in machine-readable form. Recipes are optimized sets of parameter values ​​that are functionally or procedurally related. The use of recipes ensures the reproducibility of production processes.

[0112] Furthermore, an adjustment device according to an advantageous embodiment includes supply and auxiliary and / or supplementary systems (compressed air, vacuum, electrical energy, fluids such as hydraulics, coolants, heating media, means and / or devices for temperature stabilization, electromagnetic shielding).

[0113] Furthermore, the alignment device may include frames, covers, vibration-suppressing or damping or vibration-absorbing active or passive subsystems.

[0114] Furthermore, an alignment device preferably includes at least one measuring system, preferably with measuring units for each axis of movement, which can be designed in particular as displacement measuring systems and / or as angle measuring systems. The measuring system preferably comprises at least one detection unit or an additional detection unit.

[0115] Both tactile (i.e., probing) and non-tactile measurement methods can be used. The measurement standard, the unit of measurement, can be a physical object, in particular a scale, or it can be implicitly present in the measurement method, such as the wavelength of the radiation used.

[0116] To achieve the required alignment accuracy, at least one of the following measuring systems can be selected and used. Measuring systems implement measurement procedures. In particular, the following can be used: Inductive and / or capacitive and / or resistive methods and / or comparison methods, in particular optical image recognition methods, detection of position markers and / or QR codes and / or incremental or absolute methods (with in particular glass normals as a scale, or interferometers, in particular laser interferometers, or with magnetic normals) and / or time-of-flight measurements (Doppler methods, time-of-flight methods) or other time-of-flight methods and / or triangulation methods, in particular laser triangulation, and / or autofocus methods and / or intensity measurement methods such as fiber optic rangefinders may be used.

[0117] The listed measuring methods can also be used in the device for adjustment, in particular not only to detect and correct the local relative position and / or location of the detection means to the substrate holder, but also to perform an absolute position measurement in the device.

[0118] Furthermore, a particularly preferred embodiment of the alignment device includes at least one measuring system which detects the XYZ position and / or orientation and / or angular position of at least one of the substrates and / or one of the substrate holders with respect to a defined reference, in particular the frame. The measuring system comprises at least one calibrated detection unit.

[0119] The measuring system, or rather its acquisition unit, determines 3D positions, preferably of the substrate holder with corrected angular orientation, so that height and angular position information can be derived from the measurement in addition to the planar position data. For this purpose, at least one adjustment marking field consisting of steps and / or layers with unique position markers is recorded.

[0120] A frame can be understood as a part consisting in particular of natural hard rock or mineral casting or spheroidal graphite cast iron or hydraulically bound concrete, which is in particular vibration-damped and / or vibration-isolated and / or mounted with vibration damping.

[0121] By attaching the detection units to the substrate holder and the adjustment marking field to, for example, the frame, the idea can also be advantageously reversed. In this case, the detection unit moves with the substrate holder, and the adjustment marking field is fixed to the frame.

[0122] To enable acquisition, evaluation, and control at any given time, particularly continuously, the adjustment marks of the adjustment marking field are distributed, according to an advantageous embodiment, over a larger area of ​​the respective plane than the field of view of an image acquisition system of the acquisition units, in order to supply the control unit (and / or regulating unit), particularly continuously, with measured values. However, for each position within the field of view of an image acquisition system, the adjustment marks of the adjustment marking field are designed such that height information can be acquired from the adjustment marking field and / or from the extended planar position information. In other words, for any lateral position of the substrate holder, the spatial position of the acquisition means can be determined by the arrangement of the adjustment marks of the adjustment marking field, and the correction of the angular position can be determined.Since the relative position of the detection device in particular is available as 3D position information, a more precise spatial alignment of the substrates attached to it can be carried out relative to each other.

[0123] For XYZ position determination, the alignment device can be equipped with at least one three-beam interferometer with a suitably designed, in particular monolithic, reflector for determining the XYZ position and / or orientation of the substrate holder, in addition to the at least one sensing means. For this purpose, the sensing means and the interferometer are integrated into a single assembly so that the sensing means and the interferometer do not move independently of each other.

[0124] Another advantageous embodiment of a device can, in addition to the device for detecting adjustment marks of an adjustment marking field, also include measuring means, for example, a prismatic, monolithic reflector, which is measured with several, in particular three-beam, interferometers. This eliminates error propagation through averaging, differentiation, and series measurement, and further increases alignment accuracy. In other words, sufficiently fast position measurements can be used to control the trajectory of the movement, thus further reducing positional errors of the substrate holder.

[0125] The substrate holder of the device for alignment and / or adjustment, which is formed in particular from a monolithic block, preferably has at least two of the following functions: Substrate mounting with vacuum (vacuum tracks, connections), and / or with electrostatic means, shape compensation for deformation of the substrate by means of mechanical and / or hydraulic and / or piezoelectronic and / or pyroelectric and / or electrothermal actuating elements, position and / or orientation determination (measuring standards, reflective surfaces and / or prisms, in particular the reflectors for interferometry, reference marks and / or reference mark fields, planar measuring standards for planes, volume standards, in particular steps, layer systems of known layer heights with adjustment marks subdivided into planes) movement (guide tracks).

[0126] Motion devices not used for fine adjustment are designed, in particular, as robotic systems, preferably with incremental encoders. The accuracy of these motion devices for auxiliary movements is decoupled from the accuracy for aligning the substrate stack, so that the auxiliary movements are performed with a low repeatability of less than 1 mm, preferably less than 500 micrometers, and particularly preferably less than 150 micrometers.

[0127] The control and / or regulation of the device's movement mechanism for lateral alignment (fine adjustment) is performed primarily based on the detected XYZ positions and / or alignment orientations. For this purpose, the substrate's additional alignment marks are correlated with the corresponding adjustment marks of the alignment marking field, which are uniquely assigned to these marks within a field of view on the substrate holder's surface. The height information, angular position, and their correction are calculated from the adjustment marks of the alignment marking field. This results in an XYZ position and a spatial orientation, which can be continuously observed during the alignment movement and when adjusting the distance to the bonding surface. This information is particularly useful for real-time error correction of the alignment movement.

[0128] The accuracy of the movement devices for alignment is less than 500 nm, preferably less than 100 nm, particularly preferably less than 50 nm, most preferably less than 10 nm, more preferably 5 nm, most preferably less than 1 nm.

[0129] In particularly preferred embodiments of the device, the error in the alignment accuracy of the device is less than 20% of the permissible maximum alignment error, preferably less than 10%, most preferably less than 1%.

[0130] In other words, if the permissible alignment error of the substrates is, for example, 10 nm, then the positioning error is at most 20% of the value, i.e., 2 nm.

[0131] In a particularly preferred embodiment of the substrate holder, the substrate holder can consist of several components as a non-monolithic body. The substrate support surface includes at least one adjustment marking field with the adjustment markings and, in particular, distributed, point-like supports for the support of a substrate. The substrate support surface forms part of an insert, which is a reproducibly elastically deformable body. The insert is, in particular, statically determinate and held in a base body. The substrate support surface is fluidically connected to, in particular, a vacuum via appropriately designed channels, nozzles, and supply lines; this negative pressure can also be converted to positive pressure.

[0132] The insert is clamped in the base body. At least the back side of the insert, facing away from the substrate holder surface, is insulated in a gas-tight manner within the base body of the substrate holder, so that the insert can be reproducibly deformed by means of a vacuum or overpressure.

[0133] The fluidic connection between the space of the substrate holder's base body and the back of the insert can be independently subjected to controlled overpressure or underpressure, thereby causing the deformation of the insert.

[0134] An exemplary embodiment of a method for adjusting a detection device is carried out in particular with the following sequence, including the following steps.

[0135] First process step: At least one detection device is moved to the expected position of an alignment mark on the substrate to be aligned. This positioning is subject to a positioning uncertainty.

[0136] Second process step: The substrate holder is attached so that no movement of the substrate holder occurs.

[0137] Third process step: The detection device focuses on an adjustment mark of an adjustment mark field and detects the adjustment mark.

[0138] Fourth process step: The stored position of the adjustment mark is retrieved from the knowledge base and / or a database and correlated with the measured value of the measuring device. This stores the spatial position, in particular the absolute position, of the measured adjustment mark.

[0139] Fifth process step: The detection device focuses on a further adjustment mark of a second level of the adjustment mark. In this process, only one focusing movement takes place in the device, preferably in the z-direction.

[0140] Sixth process step: the further adjustment mark is recorded and the position and location of the further adjustment mark are calculated.

[0141] Seventh process step: The relative position and / or angular orientation of the detection element with respect to the local normal direction of the substrate holder is calculated, based in particular on the height known from the memory and the calculated z-focusing height, as well as on an xy-lateral displacement of the further adjustment mark. This value can be used as a correction value for subsequent processes.

[0142] In an advantageous embodiment, the desired adjustment markings can be detected in the vicinity of the optical axis of the respective lens of the detection units at a radius of less than 3 millimeters, preferably less than 2 millimeters, particularly preferably less than 1 millimeter, most preferably less than 500 micrometers, and even more preferably less than 250 micrometers.

[0143] A measuring system with at least one detection unit for capturing adjustment marks of an adjustment marking field (in particular a measuring microscope with objective) detects a first adjustment mark of a first plane and thus an XYZ position and / or orientation of the substrate holder. The substrate holder is held in place, and the position(s) of the additional alignment mark of the lower substrate are correlated with the detected position. The adjustment marking field, which is fixed to the substrate holder, is used to detect the position of the substrate holder.

[0144] Preferably, a stage of the adjustment marking field is focused on, which is close to the free surface of the adjustment marking field and allows adjustment markings to be viewed throughout the entire depth of the adjustment marking field.

[0145] In this focused position, the focus position and thus the focus area (especially of the lens) of the detection unit for capturing the adjustment marking field is fixed. Furthermore, the detection unit is specifically fixed in place or held stationary.

[0146] During refocusing, at least one adjustment mark of a first level is detected in the initial position, and at least one adjustment mark of a second level of the adjustment mark field is detected in the target position.

[0147] The position of the substrate holder is corrected, at least in the lateral plane, using the measured positional and / or angular errors. The measuring device is moved so that the corresponding second adjustment mark of the second plane is in focus, or rather, lies within the focus range of the measuring unit. In this way, a visual inspection can ensure that the distance between the first and second planes has been approached with sufficient accuracy.

[0148] This eliminates the need to reposition the substrate holder and avoids alignment errors, as correction values ​​can be used. Height information is provided via the adjustment marker field. When aligning the substrates relative to each other, corrections can be made to their relative positions if the alignment error exceeds a defined limit. The adjustment procedure provides a correction value for these corrections.

[0149] The alignment errors for which corrections can be applied are for displacements less than 500 micrometers, preferably less than 100 micrometers, particularly preferably less than 100 nanometers, very particularly preferably less than 10 nanometers, even more preferably less than 5 nanometers, and most preferably less than 1 nanometer.

[0150] The alignment errors for which corrections for twists can be applied are less than 50 microradians, preferably less than 10 microradians, particularly preferably less than 5 microradians, very preferably less than 1 microradian, even more preferably less than 0.1 microradians, most preferably less than 0.05 microradians.

[0151] In other words, the method allows the different levels of an adjustment marking field to be measured after a sequence of defined relative movements in order to derive the relative position and / or alignment of the two measured objects to each other, in order to generate correction values ​​which in turn increase the alignment accuracy of the substrate stack.

[0152] If the observed planes of the adjustment marking field are not normal to the z-axis of at least one of the detection means, any relative movement causes a displacement in the xy-plane and / or an angular error (yaw error and / or pitch error and / or roll error), which can be detected and corrected accordingly.

[0153] A substrate holder with an integrated adjustment marking field can be understood as a standalone device. Preferably, the substrate holder incorporates the adjustment marks of at least one adjustment marking field positioned near the substrate contact surface of the substrate holder in such a way that no contact occurs between the substrate and the adjustment marks during use. In other words, the adjustment marks of the adjustment marking field and the substrate never touch when the substrate is resting on the substrate holder surface. The use of a studded sample holder with integrated adjustment marking fields is particularly advantageous.

[0154] In an advantageous embodiment of the substrate holder, the individual adjustment marks of the adjustment marking field on the substrate holder can be positioned such that they are in the vicinity of the alignment marks on the substrate. The purpose of this placement is to calibrate and / or adjust the device without a substrate using the sensing means, in particular to measure any angular error of the individual sensing means in order to use calibrated values ​​for the device during alignment. Preferably, after calibration, the sensing means are locked in position. When using the substrate holder to align substrates, the adjustment marks of the substrates can thus be detected without any readjustment movements of the sensing means.In other words, the z-axes of the adjustment marks in the adjustment mark field coincide locally with the z-axes of the substrate alignment marks within the field of view of the individual detection devices. This allows the calibrated detection devices and substrate holders to be used for substrate alignment without repositioning.

[0155] The terms that axes coincide, or coincide, or parallelism, or normality are used in this disclosure as terms of quantities subject to tolerance, so that in particular the tolerances of non-tolerated length or angle dimensions according to ISO 2768 apply unless the tolerances are explicitly stated.

[0156] Further advantages, features, and details of the invention will become apparent from the following description of preferred embodiments and from the drawings. These show schematically in: Figure 1 is a cross-sectional view of an embodiment of a device for adjusting a detection means, Figure 2a is a top view of an exemplary arrangement of the adjustment marks or adjustment marking fields between elevations of the substrate holder, Figure 2b is a sectional view of an embodiment of an adjustment marking field, Figure 3 is a top view of an embodiment of an adjustment marking field with adjustment marks, Figure 4 is a sectional view of an embodiment of an adjustment marking field with a detection unit, Figure 5a is a detection unit in a first position and Figure 5b is the detection unit in a second position.

[0157] The figures illustrate the advantages and features of the invention. The depicted embodiments are identified by reference numerals. Individual components or features with the same or equivalent function are identified by the same reference numerals.

[0158] In Fig. 1 Figure 1 shows a schematic functional representation of the device for adjusting a detection element. The device is part of an alignment system 1 for aligning and / or processing substrates. The alignment system 1 can align substrates (not shown) relative to each other and at least partially and / or temporarily bond them together (so-called pre-bonding).

[0159] The alignment system 1 includes a first substrate holder 9, onto which a first substrate can be loaded and fixed on a substrate holder surface. Furthermore, the alignment system 1 includes a second substrate holder 11, onto which a second substrate can be loaded and fixed.

[0160] The first, in particular lower, substrate holder 9 is arranged on a first motion device 10 for holding and implementing feeding and adjustment (alignment) movements of the first substrate holder 9. The second, in particular upper, substrate holder 11 is arranged on a second motion device 12 for holding and implementing feeding and adjustment (alignment) movements of the second substrate holder 11. The motion devices 10 and 12 are fixed to a common, solid table or frame 8 to reduce / minimize vibrations of the functional components. The frame may, in particular, include active vibration damping.

[0161] Optical systems 2 and 5 of alignment system 1 can also be used to detect alignment marks on the substrates (not shown). The detection means 3 and 6 (especially optics) can thus also detect warning marks on the substrate or the substrate holder. Optical system 2 is primarily designed to detect adjustment marks within an adjustment marking field.

[0162] The optical system 2, in particular the detection means 3, can be focused onto a focal plane or focus position. Within a focal area 19, at least one alignment mark can be detected. The horizontal distance (z-direction) between the alignment marks of different planes within an alignment mark field is known and can additionally be read based on the information content of an alignment mark (e.g., a QR code). Movements of the optical system 2, in particular in the X, Y, and Z directions, are carried out by means of a positioning device 4. The positioning device 4 can, in particular, be fixed to the solid frame 8.

[0163] Insofar as the optical measuring system 2 is concerned, the positioning device 4 can perform a focus with respect to an adjustment mark of a first plane 18 of an adjustment marking field 14 by moving the detection unit 3 in the Z direction. Positioning in the XY direction is also conceivable, wherein, in particular, a fixation takes place during the adjustment, preferably on the table / frame.

[0164] Furthermore, in the illustrated embodiment of the alignment system 1, the detection unit 3 can detect an adjustment mark 15 of an adjustment marking field 14 in the xyz position. After refocusing or refocusing to another plane (distance between the planes of the adjustment marking field 14 is known), the actual spatial angular position is determined from the known height of the planes or the known distance between the planes of an adjustment marking field and from the parasitic, lateral movement of the detection means 3 while the substrate holder 9 is held stationary. In this way, the wedge error of the optics 3 and the substrate holder 9, or rather the receiving surface of the substrate holder 9, is determined. The optics 3 can thus be advantageously adjusted or calibrated with respect to the substrate holder 9 using the adjustment marking field. In addition, the position of the detection means 3 can be calculated.The position can be used as a correction factor for reducing the alignment error of the substrate stack. A substrate (not shown) is received, in particular, onto the substrate holder surface 20, which consists of several individual surfaces. Preferably, the substrate receiving surface 20 consists of a plurality of knobs 21.

[0165] In the illustrated embodiment of the alignment system 1, the measuring system 5 or the detection unit 6 can also be used to detect, in particular, the XY position and / or position (especially also the rotation position) and / or the height position of the lower substrate holder 9 with particularly high accuracy.

[0166] To initiate a fusion bond, at least the upper substrate can be prestressed using a substrate prestressing device 13. The prestressing can be achieved by mechanical prestressing with a prestressing element, a so-called bond pin. In a further embodiment of the substrate prestressing device, the substrate can be prestressed with a fluid, in particular with a gas, from a nozzle, especially a movable nozzle.

[0167] With preferred embodiments of the device (not shown), the following exemplary process steps can be carried out: The first substrate is attached to the substrate holder surface of the first substrate holder 9. In particular, a mechanical and / or electrostatic clamping force is used for attachment; this clamping force is generated by a pressure difference between the ambient atmosphere and the vacuum applied to the first substrate holder 9, also known as vacuum clamping. The attachment is arranged in such a way that the first substrate does not experience any inaccurate or undesired movement relative to the first substrate holder 9 during the entire process.In particular, thermal expansion can be prevented or reduced if the first substrate holder 9 and the first substrate each have a corresponding, preferably linearly corresponding, coefficient of thermal expansion, wherein the difference between the coefficients of thermal expansion and / or the linear progression of the coefficients of thermal expansion is preferably less than 5%, preferably less than 3%, and particularly preferably less than 1%.

[0168] The system is preferably operated in a temperature-stabilized environment, in particular in a cleanroom, in which the temperature fluctuation is less than 0.5 Kelvin, preferably less than 0.1 Kelvin, particularly preferably less than 0.05 Kelvin, most preferably less than 0.01 Kelvin during an adjustment or alignment cycle.

[0169] The fixed first substrate and in particular an insert of the substrate holder 9 can be understood as a quasi-monolithic body for the execution of the movements of the first substrate, which do not allow any relative movements to each other.

[0170] This substrate fastening can be positive-locking and / or preferably force-locking. The quasi-monolithic connection ensures that the influences that can cause displacement, rotation, and / or deformation between the substrate holder and the substrate are at least reduced, preferably reduced by at least one order of magnitude, and most preferably eliminated. Thus, together with the adjustment of the detection means 3 to the substrate holder, the alignment error can be further reduced.

[0171] The substrate can be connected to the substrate holder 9 by means of a positive or force-fit connection, in such a way that, in particular, the difference in thermal expansion can be suppressed. Furthermore, the substrate holder can be used to reduce, eliminate, and / or correct the independent deformation of the substrate. In addition to these measures, at least one detection element is positioned relative to the substrate holder, specifically relative to the adjustment markings of the adjustment marking field on the substrate holder surface, in a defined position and angle. This allows, on the one hand, the slow relative thermal movements to be detected and corrected, and on the other hand, the positioning errors of the substrate holder relative to the detection element can be at least reduced by pre-adjusting the position and angle of the detection element.

[0172] In one embodiment, both the lower substrate holder 9 and the upper substrate holder 11 can include additional passively and / or actively operated deformation elements and / or intermediate plates, also called inserts, to minimize the mechanical and / or thermal properties of the substrates for the reduction of the residual alignment error after joining.

[0173] The first substrate holder 9 can be located in an optical path of the detection unit 3 during the detection of a first adjustment mark 15 of an adjustment mark field 14.

[0174] Preferably, a detection unit, or equivalently a detection means, is arranged aligned with or perpendicular to a defined adjustment mark of an adjustment marking field 14, so that detecting an alignment mark of a substrate to be bonded in the same xy position does not require repositioning of the substrate holder and / or the detection means. In this way, by reducing the required movements and detecting and adjusting positions, the accuracy of the substrate stack alignment is increased.

[0175] The lower substrate holder features adjustment marks 15 of the adjustment marking field 14. The XYZ position and orientation of each adjustment mark 15 within the adjustment marking field can be determined using these adjustment marks 15. By detecting another adjustment mark 15 in a different plane of the same adjustment marking field 14, the wedge error or angular position of the substrate holder 9 relative to the detection means 3 can be determined.

[0176] It is conceivable that instead of a relative movement (or refocusing) of the detection element 3, the substrate holder 9 performs a relative movement in the Z-direction and the detection element is held in place. From this adjustment procedure, a similar correction value for a relative position can be calculated, which in particular determines a parasitic movement of the substrate holder relative to the held detection element.

[0177] The detection unit 6 can also be used to detect adjustment marks 15 on different levels of one of the adjustment marking field 14 if the substrate holder for the detection unit 6 is transparent.

[0178] The measured values ​​(XY position and / or orientation of the first substrate as well as XYZ position and / or orientation of the first substrate holder 9 or the first substrate) can be correlated with each other after the adjustment / correction has been applied, so that the XYZ position of the substrate holder 9 and / or the sensing device can be reproduced. This allows the substrate attached to the substrate holder 9 to be moved in a controlled manner for alignment and for setting the bond distance, without the adjustment markings 15 of the substrate holder 9 or the alignment markings of a substrate being directly observable.

[0179] By assigning the position of the substrate to the spatial position and / or orientation of the substrate holder 9 or the sensing element 3, alignment becomes possible without directly observing the XYZ positions and / or orientations and / or relative angular positions of the respective substrate during alignment and / or contacting. The determined correction values ​​increase positioning accuracy by reducing positioning uncertainties before and during the alignment and contacting of a first substrate with a second substrate. Furthermore, the distance between the substrates can be precisely set and / or minimized during alignment; for this purpose, additional adjustment marking fields can be used, particularly on the reverse side of the substrate holder facing away from the substrate receiving surface.

[0180] In particular, a repeatability of the positioning (measured as relative alignment error between the two substrates), also known as backlash, of less than 500 nm, preferably less than 100 nm, particularly preferably less than 30 nm, most preferably less than 10 nm, even more preferably less than 5 nm, and most preferably less than 1 nm is achieved.

[0181] The backlash results from the movements of the motion devices; only the detection location varies, so the measured quantity exists as a relative alignment error. The method reduces the local positioning inaccuracy by locally measuring the misalignment of the detection device 3, which consequently further reduces the local alignment error.

[0182] To further increase alignment accuracy, a first acquisition unit 3 can be operated in a time-synchronized manner with at least one additional acquisition unit 6. The time difference between the acquisition of the measured values ​​is less than 3 seconds, preferably less than 1 second, particularly preferably less than 500 milliseconds, most preferably less than 100 milliseconds, in a still more preferred case less than 10 milliseconds, most preferably less than 1 millisecond, and ideally, simultaneously. This is particularly advantageous because the effects of disturbances such as mechanical vibrations can be eliminated. Mechanical vibrations propagate through materials at speeds of several thousand m / s, including structure-borne sound. If a control system and the acquisition means operate faster than the propagation speed of structure-borne sound, the disturbance is reduced or eliminated.

[0183] If a detection unit 3 and the detection unit 6 are synchronized to detect the adjustment marking field 14 and another adjustment marking field on the back of the substrate holder (in particular by simultaneous triggering of the detection as well as compensation of the detection time and / or equal integration time for camera systems), some interferences can be reduced, in the best case eliminated, since the detection should take place at a time in which the interferences have the least possible effect on the detection accuracy.

[0184] In a preferred embodiment of the method and the device for adjusting a detection element, as well as in the adjustment device itself, the detection is synchronized in the case of known, especially periodic, disturbances, particularly at the peak of the vibration. Preferably, vibration sensors (accelerometers, interferometers, vibrometers) can be installed beforehand at locations on the device relevant to accuracy. The disturbances are detected by these vibration sensors and taken into account or corrected for elimination by calculation. In a further embodiment, the vibration sensors can be permanently installed at characteristic locations on the system.

[0185] For the adjustment of the detection device or, if applicable, several detection devices, it is advantageous if the adjustment marking field 14 is completely measured and the target values ​​are stored in a memory for comparison or difference calculation. The target value includes, in particular, image data of the adjustment marks of the adjustment marking field 14 of the first substrate holder 9 and / or control parameters such as trajectories for optimal approach to the spatial position and / or, in particular, machine-readable values ​​for the drives, especially for focusing the detection device 3. In other words, the position of the individual adjustment marks of one adjustment marking field and further adjustment marks of another adjustment marking field is known and stored.

[0186] Figure 2ashows several adjustment marking fields in a schematic, greatly enlarged top view, each with an exemplary selected and visible adjustment mark 15.

[0187] The individual adjustment marks 15 symbolically and schematically represent an absolute, unambiguous encoding of the position and orientation of each individual adjustment mark 15. The individual adjustment marks 15 can be located in different planes of the adjustment marking field. Since the xyz position of each alignment mark 15 is known, it is sufficient for position detection of the substrate holder (not shown) that one coded adjustment mark 15 is detected. Therefore, refocusing (or relative movement in the z-direction with the same focus) to another adjustment mark 15 within the same adjustment marking field is possible, allowing the angular position / wedge error of the detection element relative to the substrate holder to be determined.The adjustment of the detection device can therefore be advantageously carried out using an adjustment marking field.

[0188] Figure 2b Figure 1 shows an adjustment marking field 14" with different layers 16, 16' or steps. The adjustment marks of one step are thus arranged in a plane and have a specific and known distance to the adjustment marks of another step or layer of the adjustment marking field 14". In the illustrated embodiment, the adjustment marking field 14" is arranged between the raised areas or knobs 21'.

[0189] The adjustment marking field 14" is fixed in position relative to the substrate holder or the substrate holder surface 20. The raised support surfaces 21' (for receiving the substrate) are higher than the highest point of the adjustment marking field 14" or are located at a greater distance from the substrate holder surface. The adjustment marking fields are thus offset from the substrate holder receiving surface (support surfaces of the raised surfaces). This advantageously prevents the adjustment marks (of the uppermost level of the respective adjustment marking field) from coming into contact with the substrate.

[0190] The reduced contact area of ​​the 21' studs means that the substrate does not lie flat against the surface, so any particles present on the back of the substrate do not cause distortion. This effectively minimizes cross-contamination of the substrate or the substrate holder.

[0191] The adjustment marking field is fixed to the substrate holder. In particular, the adjustment marks can be located on different levels or on several steps and / or layers 16, 16' successively within the field of view or focus area of ​​the detection unit 3 and thus be detected. Due to the known step heights or the known distances between the levels and the known positions of the adjustment marks, these can be used to determine the angular error of the refocused detection element.

[0192] It is possible that a modified method is used to determine correction values ​​from the position and angular orientation of the sensing device, which measures layers 16 and 16' of the adjustment marking field 14" in particular with the following steps and sequence: In a first step, the substrate holder is raised by the substrate thickness in a z-direction. In a second step, at least one sensing device 3 is moved to the expected xy-position of the substrate's alignment mark and held in xy. In a third step, at least one sensing device is focused on an adjustment mark of an adjustment marking field 14 of the substrate holder, and the adjustment mark is recorded in xy-position as well as a rotation about the z-axis.In a fourth process step, the substrate holder is moved away from the fixed detection element in a Z-direction, so that another adjustment mark of a different plane or layer 16 or 16' can be detected. In a fifth process step, an adjustment mark of the corresponding layer 16 or 16' and the relative displacement resulting from the movement of the substrate holder and the parasitic movements are determined and compared with the ideal values ​​to calculate the correction values. A correction value for the angular position of the relative position between the substrate holder and the detection element is calculated. Subsequently, the detection element is adjusted, or the wedge error is compensated for.

[0193] The distance between the planes is between 1 micrometer and 300 micrometers, preferably between 5 micrometers and 200 micrometers, more preferably between 10 micrometers and 100 micrometers, particularly preferably between 25 micrometers and 75 micrometers, and most preferably between 48 micrometers and 52 micrometers. For example, the distance between the planes is 50.00 micrometers.

[0194] Furthermore, it is advantageous if the respective additional adjustment marks 15, 15' have detectable positional information. With a multitude of adjustment marking fields between the raised areas / nubs 21, 21', it is possible to determine the angular position or wedge error between the substrate holder and the detection element at a correspondingly large number of points without having to move the detection element in the xy direction. Since the position of the respective detected adjustment mark 15, 15' relative to the adjustment marks 15 of the adjustment marking field is known, this positional information can be used to optimize movements or to adjust distances, in particular bond gaps. Preferably, not only is the position of the detected adjustment mark 15, 15' relative to the adjustment marks 15, 15' of the same plane known, but also the position of the respective plane of the detected adjustment mark 15, 15' relative to the other planes of the adjustment marking field.

[0195] Figure 3 Figure 1 shows a section of a possible embodiment of an adjustment marking field 14", wherein the individual exemplary adjustment marks 15' are supplemented with a machine-readable code. The individual adjustment marks 15 can be arranged on different levels (steps and / or layers), and the code may contain an indication of which level each mark belongs to. Furthermore, the code may contain a unique indication of the position and orientation of each adjustment mark 15'.

[0196] In Figure 4Figure 1 shows a cross-sectional view of an embodiment of an adjustment marking field 14ʺʺ. The adjustment marks 15' of the adjustment marking field 14ʺʺ are arranged in three different planes 18, 18', 18'' and can be detected by the detection unit 3. The detection unit 3 can only detect the adjustment marks 15' within the focus area 19. It is also conceivable that the detection unit 3 uses electromagnetic radiation of different wavelengths to detect adjustment marks arranged one above the other in different planes. The adjustment marking field is then at least partially transparent to the different wavelengths.

[0197] A first level 18 has a known distance 17" to a second level 18'. The second level 18' has a known distance 17' to a third level 18''. Furthermore, the distance 17 between the first level 18 and the third level 18'' is known. In the illustrated embodiment, the distance 17" and the distance 17' are of different sizes, so that when using the adjustment marking field 14ʺʺ to adjust a detection element, all three distances 17, 17', and 17" can be approached or adjusted. Thus, the different distances between the detection element 3 and an adjustment mark can be detected. Simultaneously, the known distance to another level can be advantageously approached.

[0198] Combinations of distances 17, 17', 17" can also be achieved by repeatedly moving the substrate holder (9), which is stationary relative to the adjustment marking field 14'', as a focusing movement of the detection element 3. For example, the focused distance 17" can first be set, and then the distance 17' can be moved to the same distance in the same direction. Alternatively, the substrate holder can be moved by twice the distance 17" for example. This is done by aligning in two steps, and the detection unit is adjusted accordingly between the steps, as a focus position, and thus the focus area 19 of the detection unit 3, is adjusted.

[0199] In the Figures 5a and 5bThe optics 3 are shown in a first position 23 and in a second position 24 (after adjustment). The wedge error (angle 22) between the optics 3 and the substrate holder, i.e., the angular error between an optical axis 25 of the optics 3 and the substrate holder surface 20 of the substrate holder 9, is present in the first position 23 and is compensated for or no longer present in the second position 24. The optics 3 can therefore be advantageously adjusted by detecting two adjustment marks on different planes 18, 18', 18"". Reference symbol list

[0200] 1 Alignment system with device for adjusting a detection element 2 Optical system 3 Detection element, detection unit, optics 4 Positioning device 5 Additional measuring system 6 Detection unit for substrate holder rear, additional detection element 7 Positioning device of the additional measuring system 8 Frame, table 9 Substrate holder, first (to be aligned) substrate holder 10 Movement device of the substrate holder to be aligned 11 Second substrate holder 12 Second movement device 13 Substrate deformation device 14, 14', 14'', 14‴ Adjustment marking field, alignment marking field 15, 15' Adjustment marks, adjustment marks, reference marks 16, 16' Layers of an adjustment marking field 17, 17', 17" Spacing of the superimposed adjustment marks 18, 18', 18" Planes of the adjustment marking field 19Focus area of ​​the detection means, focus area of ​​the optics 20Substrate holder surface 21, 21'Raises, pins, knobs 22Angles,Wedge error 23 first position 24 second (adjusted) position 25 optical axis,

Claims

1. A device for adjusting a detection means (3, 6), at least comprising i) a substrate holder (9) for mounting a substrate, ii) at least one adjustment marking field (14, 14', 14", 14‴) with adjustment marks (15, 15') arranged fixed with respect to the substrate holder (9) and iii) the detection means (3, 6) for detecting the adjustment marks (15, 15'), characterised in that the detection means (3, 6) is adjustable relative to the substrate holder (9) with the aid of adjustment marks (15, 15') of the adjustment marking field (14, 14', 14", 14"') arranged above one another, wherein the substrate holder (9) comprises elevations (21, 21') arranged regularly on a substrate holder surface (20) for providing a substrate mounting surface and wherein a plurality of adjustment marking fields (14, 14', 14", 14"') each comprising adjustment marks (15, 15') are arranged regularly offset from one another between the elevations (21, 21').

2. The device according to claim 1, wherein the adjustment marks (15, 15') of the adjustment marking field (14, 14', 14", 14‴) are arranged in a first plane (18, 18', 18") and a second plane (18, 18', 18"), and wherein the second first plane (18, 18', 18") and the second plane (18, 18', 18") are arranged parallel to one other, and wherein the first plane (18, 18', 18") and the second plane (18, 18', 18") have a distance (17, 17', 17") from each other.

3. The device according to at least one of the preceding claims, wherein the detection means (3, 6) can be adjusted by a relative movement between the detection means (3, 6) and the substrate holder (9).

4. The device according to at least one of the preceding claims, wherein the detection means (3, 6) can be adjusted by a change of focus of the detection means (3, 6).

5. The device according to at least one of the preceding claims, wherein the adjustment marks (15, 15') of the first plane (18, 18', 18") and the adjustment marks (15, 15') of the second plane (18, 18', 18") are arranged aligned one above the other.

6. The device according to at least one of the preceding claims, wherein the adjustment marks (15, 15') of the first plane (18, 18', 18") and the adjustment marks (15, 15') of the second plane (18, 18', 18") are arranged above one another and regularly offset with respect to one another.

7. The device according to at least one of the preceding claims, wherein the adjustment marks (15, 15') of the first plane (18, 18', 18") and the adjustment marks (15, 15') of the second plane (18, 18', 18") are arranged offset step-like with respect to one another on different layers (16, 16').

8. The device according to at least one of the preceding claims, wherein the adjustment marks (15, 15') each also contain individual information content which is detectable by the detection means (3, 6).

9. The device according to at least one of the preceding claims, wherein the detection means (3, 6) is an optical detection means, in particular a lens with a determinable optical central axis.

10. A device according to at least one of the preceding claims, wherein one of the two planes of the at least one adjustment marking field (14, 14', 14", 14‴) lies on the substrate holder surface (20).

11. The device according to at least one of the preceding claims, wherein the at least one adjustment marking field (14, 14', 14", 14"') is completely embedded in the substrate holder (9) and which is at least partially arranged below the substrate holder surface (20).

12. The device according to at least one of the preceding claims, wherein the detection means (3, 6) can the used for reading out alignment markings of a substrate.

13. A method for adjusting a detection means with at least the following steps: i) provision of a substrate holder (9) with an adjustment marking field (14, 14', 14", 14‴) with adjustment marks (15, 15') arranged fixed with respect to the substrate holder (9) ' and i) adjustment of the detection means (3, 6) relative to the substrate holder (9), characterised in that the detection means (3, 6) is adjusted with the aid of adjustment marks (15, 15') of the adjustment marking field (14, 14', 14" 14‴) arranged above one another, wherein the substrate holder (9) comprises elevations (21, 21') arranged regularly on a substrate holder surface (20) for the provision of a substrate mounting surface and wherein a plurality of adjustment marking fields (14, 14', 14", 14"') each comprising adjustment marks (15, 15') are arranged regularly offset from one another between the elevations (21, 21').

14. The method according to claim 13, wherein the adjustment of the detection means in step ii) involves the following steps with the following sequence: a) detection of a first adjustment mark of a first plane (18, 18', 18") of the adjustment marking field (14, 14', 14", 14‴), b) detection of a second adjustment mark of a second plane (18, 18', 18") of the adjustment marking field (14, 14', 14", 14"'), c) determination of a wedge error between the detection means (3, 6) and the substrate holder (9), d) compensation for the wedge error determined in step c), wherein the first plane (18, 18', 18") and the second plane (18, 18', 18") are arranged parallel to one another, and the first plane (18, 18', 18") and the second plane (18, 18', 18") have a distance (17, 17', 17") from one another.