Apparatus and method for adjusting a detection means - Patent application

Abstract

The present invention relates to a method and device for adjusting a detection means on the basis of adjustment marks arranged above and below.

Description

[Technical field]

[0001] DEVICE AND METHOD FOR ADJUSTING DETECTION MEANS FIELD OF THE DEVICE AND METHOD FIELD OF THE DEVICE The invention relates to an apparatus and method for adjusting detection means The apparatus and method are particularly suitable for adjusting detection means in alignment and processing facilities in the semiconductor industry.

[0002] In the semiconductor industry, aligners are used to align substrates, especially wafers, with respect to each other or to other components. The substrates may have any shape, but are preferably circular. The diameter of the substrate is especially standardized industrially. Industrially common diameters for wafers are 1 inch (2.54 cm), 2 inch (5.08 cm), 3 inch (7.62 cm), 4 inch (10.16 cm), 5 inch (12.7 cm), 6 inch (15.24 cm), 8 inch (20.32 cm), 12 inch (30.48 cm) and 18 inch (45.72 cm).

[0003] The joining of aligned semiconductor substrates is called bonding. In order to avoid bonding errors and to keep scrap rates low, it is necessary to align the substrates or a substrate as accurately as possible. Furthermore, many applications require the highest possible precision. For this purpose, alignment marks on the substrates or on the substrate holder are measured relative to one another. In particular, optical detection means are used, which detect the alignment markings and align the substrates.

[0004] For example, during bonding, the substrates to be bonded are aligned with one another and are connected to one another in a subsequent process step. A particularly precise alignment of the substrates with respect to one another is always required here. In the following text, the bonding is preferably fusion bonding. An alignment process in which alignment markings are provided on the surfaces of the substrates to be bonded is called face-to-face alignment. During alignment, the relatively large travel distances involved lead to large alignment errors.

[0005] Another problem with the prior art is that ever increasing alignment accuracy requirements can no longer be met by simple means, such as by methods where the substrate is measured relative to a reference point and aligned blindly after, for example, bringing it close to a contact.

[0006] For example, the publication US6214692 is based on the comparison of two images of the alignment markings and the position correction. The locations of the alignment markings on two substrates placed face-to-face are detected separately using a camera system. From the calculated relative locations and relative positions of the alignment markings, the positioning tables (substrate holder and stage) are driven and controlled so that incorrect positions are corrected.

[0007] Another publication, US Pat. No. 10,692,747, is based on the comparison and position correction of a total of three images of flat alignment markings. The locations of the alignment markings on two substrates placed face-to-face are detected separately using a camera system. A third detection unit detects the third alignment marking, which creates a correlation between the alignment marks of the substrates and the backside of the substrate holder or the backside of the substrate, which allows a more accurate alignment of the two substrates.

[0008] In this respect, visual control during face-to-face alignment of two substrates is either not possible or only possible if at least one of the substrates is at least partially transparent, and therefore precise alignment of the surfaces during face-to-face alignment is laborious and only possible to a limited extent.

[0009] It has proved to be particularly disadvantageous that the optical detection means of the individual alignment markings are arranged at an inaccurately defined location relative to the substrate holder and thus also positioned relative to the substrate which is subsequently placed on the substrate holder. Due to the inaccurate positioning of the detection means, detection of the individual alignment markings generally requires readjustment and focusing movements in the lateral plane of the substrate holder. By specifically controlling the movement of the detection means, the spatial location of the detection means, in particular optical detection means, for example a measuring microscope, is often so inaccurate that these detection means do not allow accurate measurements and thus a sufficiently accurate alignment of the substrate stack.

[0010] In particular, readjustment movements of the optical system for detecting the alignment marks are accompanied by parasitic movements superimposed on the necessary movements, which cause deviations from the ideal movements of the respective optical system, and thus can lead to tilted positions of the central axes of the detection means during the movements, which also have a negative effect on the alignment accuracy.

[0011] It is therefore an object of the present invention to provide an improved device and an improved method for adjusting the detection means, which at least partially eliminates, in particular completely eliminates, the drawbacks mentioned in the prior art. It is further an object of the present invention to provide an improved device and an improved method for adjusting the detection means. It is further an object of the present invention to provide an device and a method for adjusting the detection means, which takes into account the relative tilt with respect to the substrate holder and which can be easily implemented. Another object of the present invention is in particular to provide a method and a device for improving the alignment of the substrate, which in particular reliably, precisely and simply identifies and compensates for, i.e. adjusts, the wedge error between the substrate holder and the detection means.

[0012] This problem is solved by the features of the juxtaposed independent claims. Advantageous developments of the invention are set out in the dependent claims. All combinations of at least two features shown in the description, claims and / or drawings are also included within the scope of the invention. In the presented value ranges, values ​​lying within the enumerated boundaries are also to be considered as disclosed as boundary values ​​and may be claimed in any combination.

[0013] The invention therefore relates to a device for adjusting a detection means, said device comprising at least i) a substrate holder for receiving a substrate; ii) at least one alignment marking field with an alignment mark, arranged in a fixed position relative to the substrate holder; and iii) detection means for detecting the alignment marks, The detection means is characterized in that it is adjustable relative to the substrate holder based on adjustment marks of adjustment marking fields arranged above and below.

[0014] The invention further relates to a method for adjusting a detection means, said method comprising at least the following steps: i) providing a substrate holder arranged in a fixed position relative to the substrate holder and having an alignment marking field with an alignment mark; ii) adjusting the detection means relative to the substrate holder, characterized in that the detection means are adjusted based on adjustment marks of adjustment marking fields arranged above and below.

[0015] In other words, the detection means is preferably aligned on the basis of two adjustment markings of the adjustment marking field, which are arranged one above the other at different heights. In this case, it is particularly preferred that a wedge error (angular error) between the detection means and the substrate holder is compensated. As a result, the tilt position of the detection means can be adjusted and calibrated on the basis of only one adjustment marking field with adjustment marks arranged one above the other. In this publication, the terms wedge error and angular error are used synonymously.

[0016] The detection means are preferably also configured to simultaneously read out the alignment marks (on the substrate or on the substrate holder) during bonding, so that the alignment accuracy is also increased by the preceding adjustment. In particular, the substrate holder is further configured to receive and prepare the substrate as flat as possible. The alignment marking fields are arranged in a fixed position relative to the substrate holder, so that the respective alignment marks likewise have a specific or known position with respect to the substrate holder. Here, the respective positions of the individual alignment marks in the alignment marking fields are preferably known, so that after detecting two alignment marks arranged one above the other by the detection means, alignment can be performed on the basis of the detected alignment markings having known positions. For this purpose, detection means or parallel axis errors can be compensated on the basis of the alignment marks arranged one above the other without a relative movement parallel to the substrate holder (xy-axis). After such an adjustment, in particular the detection axis of the detection means is aligned perpendicular to the substrate holder, so that tilted positions no longer occur or the angular errors of the detection means can be eliminated by the device. This also reduces scrap rates during substrate processing, since any unknown angular error of the sensing means can result in alignment errors.

[0017] For this purpose, the detection means can be moved, in particular by a movement device, in particular along the focal axis (in the z-direction perpendicular to the substrate holder). Advantageously, furthermore, the tilted or inclined position of the detection unit can be compensated for by a particularly sensitive actuator. The wedge error determined between the detection unit and the substrate holder or the substrate receiving surface of the substrate holder can also result from a compensating movement of the substrate holder.

[0018] The adjustment marks are in particular markings attached to and / or in the substrate holder, which markings allow an adjustment of at least one of the detection means relative to the substrate holder. Preferably, a number of adjustment marking fields, each with its own adjustment mark, are distributed on the substrate holder, preferably in specific areas that are aligned with the positions of the subsequent alignment marks.

[0019] This allows the detection unit to advantageously detect the alignment marks of the alignment marking field independently of the xy position, whereby a further movement is possible for reading out the alignment marks without the need to move the detection means in the xy direction.

[0020] A special advantage of the adjustment device and method is that no reference wafer or other additional measuring system is required to align the detection means and the substrate holder with respect to one another. This allows this form of calibration to be carried out easily and frequently between the individual processing steps. Another very special advantage of the adjustment device and method is that the detection means is specifically adjusted at the location where the measurement is also carried out by means of a number of adjustment marking fields at different positions. This allows for external influences, such as bending of the table due to the weight of the optics, to be taken into account and does not result in a tilted position of the detection unit later.

[0021] The substrate holder with at least one alignment marking field may be composed of a number of separate components. The substrate receiving surface is preferably a repeatable, at least slightly deformable plate, which is in particular held in the substrate holder without restraint. The alignment marking field is composed of at least one alignment mark and another alignment mark.

[0022] The alignment marking field is arranged in a positionally fixed manner relative to the substrate holder or relative to the substrate holder surface, where in particular the exact location of the alignment marking field and the respective location of the alignment marks in the alignment marking field relative to the substrate holder or on the substrate holder are known, where the alignment mark or at least two alignment marks of the alignment marking field are arranged one above the other.

[0023] In a preferred embodiment of the device, the alignment marks of the adjustment marking fields are arranged in a first and a second plane, the first and second planes being arranged parallel to one another and the first and second planes being determined to have a distance from one another. In other words, the adjustment marks of the different planes have a known and constant distance from one another. In this way, the adjustment can be advantageously performed precisely. Preferably, the planes of all adjustment marking fields are arranged identically relative to the substrate holder. Due to the known distance, the wedge error between the detection means and the substrate holder can advantageously be determined precisely, in particular calculated.

[0024] In another preferred embodiment of the device, the detection means is specified to be adjustable by a relative movement between the detection means and the substrate holder. In other words, after detecting the first adjustment mark in the first plane, the second adjustment mark in the 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 path of movement can be compared with the spacing between the planes of the adjustment marking field, and thus the tilt position or wedge error can be determined.

[0025] In another preferred embodiment of the device, the detection means is specified to be adjustable by changing the focus of the detection means. In other words, the detection means moves its focus area in order to detect the respective different adjustment marks. Here, this focus movement is preferably performed without a relative movement of the detection means or the substrate holder. As a result, for example, based on the focus movement of the optical system, the distances determined in this way between the adjustment marks of the different planes are measured and compared with known distances. In this way, a particularly accurate adjustment of the substrate holder to the detection means is possible without errors resulting from relative movements. Due to this refocusing of the detection means, if an apparent lateral deviation of the adjustment marks of the two planes is detected during the focus movement, the lateral displacement can be identified and corrected accordingly. In this case, the substrate holder preferably remains fixed in its position.

[0026] In a preferred embodiment of the device, the alignment marks of the first plane and the alignment marks of the second plane are specified to be arranged one above the other, in which case the alignment marking fields and the detection means are configured to allow detection of the different alignment marks in alignment.

[0027] For example, the coordinated marking field is transparent to a given wavelength.

[0028] In another preferred embodiment of the device, the alignment marks of the first plane and the alignment marks of the second plane are specified to be arranged one above the other and regularly offset from one another, in such a way that the alignment marks can be advantageously easily detected by the detection unit.

[0029] In another preferred embodiment of the device, the adjustment marks of the first plane and the adjustment marks of the second plane are specified to be arranged in different layers, offset from one another. In this way, advantageously, the adjustment marks of the different planes are not covered by the material of the adjustment marking field. Furthermore, it is possible to select from a plurality of detection means.

[0030] In another preferred embodiment of the device, the alignment marks are additionally specified in each case to be detectable by the detection means and to include individual information content. In this way, the positions of the alignment marks, which are respectively detected in the alignment marking field and / or relative to the substrate holder, are known. In this case, the known xy positions of the alignment marks as well as their individual pattern (e.g. pixel) positions are preferably known. This advantageously allows the information content (e.g. prepared as a bar code) to be captured when determining the wedge error. This allows the wedge error to be determined more accurately and reliably. This also allows the position of the substrate to be relatively determined later on the basis of the alignment marks.

[0031] In another preferred embodiment of the device, the detection means is specified to be an optical detection means, in particular an optical system with a determinable central optical axis, which, in the case of optimal alignment, is exactly perpendicular to the substrate holder or to the substrate holder surface and thus also perpendicular to the alignment mark, so that the movement of the focal region along the central optical axis can be determined particularly precisely on the basis of refocusing or focus change.

[0032] In another preferred embodiment of the device, for preparing the substrate receiving surface, the substrate holder has regularly arranged ridges on the substrate holder surface, and a number of adjustment marking fields, each having an adjustment mark, are specified between the ridges, regularly offset from one another. The ridges are preferably projections or pins. In this way, the contact area between the substrate and the substrate holder or the substrate receiving surface is advantageously small, which can minimize or prevent contamination of the surface of the substrate. By means of the adjustment marking fields arranged between the ridges, the wedge error can advantageously be determined at a number of positions. This makes it unnecessary to perform a relative movement of the detection means in the xy direction, i.e. along the substrate holder surface. Rather, in this way, the detection means can advantageously determine the wedge error precisely and position-independently, and the detection means can be precisely aligned or adjusted.

[0033] In another preferred embodiment of the device, at least one adjustment marking field is specified to have a lower height relative to the substrate holder surface than the raised portion, so that the raised portion protrudes relative to the substrate holder surface relative to the adjustment marking field. In this way, the substrate is advantageously not contaminated by the adjustment marking field, since contact is made only by the raised portion provided for this purpose.

[0034] In another preferred embodiment of the device, one of the two planes of the at least one adjustment marking field is specified to lie on the substrate holder surface. In other words, the plane of the adjustment marking field is formed by the substrate holder surface. In this case, the adjustment mark can be partially embedded in the substrate holder or arranged below the substrate holder surface. In this way, the adjustment marking field can be configured particularly simply and with little error. Furthermore, the adjustment marking field can be directly integrated into the substrate holder.

[0035] In another preferred embodiment of the device, at least one adjustment marking field is specified to be completely embedded in the substrate holder and at least partially located below the substrate holder surface. In other words, a plane is engraved in the substrate holder and has a negative height profile with respect to the substrate holder surface. In this way, the adjustment marking field can be advantageously embedded in the substrate holder and directly formed during production. Furthermore, the adjustment marking field is advantageously protected.

[0036] In another preferred embodiment of the device, the detection means is specified such that it can be used to read out the alignment markings of the substrate. In this case, the alignment marking fields are particularly preferably arranged in areas of the substrate holder surface that generally align with the positions of the alignment marking fields of the substrate or substrate holder. In this way, the detection means can advantageously also align the alignment markings without the need for a relative movement in the xy direction. Instead, the detection means preferably remains stationary and the readout can be performed by a focus movement or a movement of the focal area.

[0037] In one embodiment of the device, the device is configured to be hermetically sealed, whereby at least the substrate holder and the detection means are integrated into an equipment chamber that can be closed air-tight and / or vacuum-tight from the atmosphere. Corresponding auxiliary units include, for example, inlets, gates, pumps, sensors, sight glasses, gas supplies, and temperature control devices. In this embodiment, the equipment chamber can be filled with a special atmosphere that preferably does not contain water or water vapor. Furthermore, this special atmosphere may be oxygen-free. In another embodiment, the equipment chamber can be subjected to a vacuum, preferably a high vacuum, particularly preferably an ultra-high vacuum. The vacuum in the equipment chamber in this embodiment is less than 1×10E-3 mbar, preferably less than 1×10E-5 mbar, particularly preferably less than 1×10E-8 mbar, particularly very preferably less than 5×10E-9 mbar, most preferably less than 1×10E-10 mbar, and in the ideal case 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 in the following order: a) detecting a first alignment mark in a first plane of an alignment marking field; b) detecting a second alignment mark in a second plane of the alignment marking field; c) determining a wedge error between the detection means and the substrate holder; d) compensating for the wedge error determined in step c), The first plane and the second plane are disposed parallel to each other, and are specified to have a gap between them.

[0039] The method advantageously allows the adjustment of the detection means or compensation of wedge errors without a reference wafer or another additional measurement system. This form of calibration can be repeated many times between wafer bonding processes without the need to move the detection means. Furthermore, the detection means advantageously remains stationary and only a focus change or focus area movement can be performed to detect the adjustment marks in different planes of the adjustment marking field.

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

[0041] Thus, when detecting the adjustment marks and then detecting the adjustment marks arranged above them, the respective known locations or distances between the planes of the adjustment marks can be compared with the detected measured values. Since the nature and structure as well as the location of the adjustment marking field are preferably known, this allows a known distance between the adjustment marks to be determined and used for the correction of the optical detection means. Based on this known distance, for example by moving the optical detection means relative to the fixed adjustment marking field of the substrate holder, an adjustment and / or correction of the detection means can be carried out based on the adjustment marks arranged above and below, without the need to move the substrate holder. In this way, the optical detection means can be aligned particularly accurately in at least one direction, since the known distances and spatial positions between the adjustment marks arranged above and below are detected and thus the actual positions and angular positions of the respective optical detection means can be calculated.

[0042] The mutual positions of the different alignment marking fields are preferably known as well, so that the positions of all alignment marks on the substrate holder are known. Here, the alignment marking fields are positioned on the substrate holder, preferably in the edge region of the surface of the circular substrate holder. In other words, the alignment marking fields are clustered in certain regions, in particular in regions where the alignment markings are generally aligned later during processing of the substrate. That is to say, the alignment marking fields are preferably provided at spatially distributed positions on the substrate holder, at positions where the substrates to be aligned and bonded contain alignment marks. Thus, the positions and spatial alignment positions of the respective optical detection means can be calculated relative to the substrate holder, and deviations from the ideal position can be used as correction values ​​for bonding the upper substrate to the lower substrate.

[0043] The substrate holder preferably has a flat substrate-receiving surface, where this substrate-receiving surface of the substrate holder is composed of a plurality of, in particular uniformly distributed, restraint points and / or projections.

[0044] In another embodiment of the substrate holder, the substrate support surface has a settable shape, which can be set depending on the respective substrate to be mounted, while the location of the respective alignment markings remains known.

[0045] Furthermore, the adjustment marking fields are arranged below with respect to the substrate placement surface and are preferably regularly offset between the placement points, so that the substrate does not come into contact with the adjustment markings.

[0046] In a particularly advantageous embodiment of the substrate holder, the adjustment marking and the at least one further adjustment marking are provided in the movement area of ​​the optical detection means and the further optical detection means, which allows an even more precise adjustment of the detection means.

[0047] The adjustment of the detection means relative to the substrate holder is used to eliminate or at least reduce error components that impair the substrate alignment result due to positional and / or angular errors of the detection means, particularly during fusion bonding. By determining the alignment of the detection means relative to the substrate holder and the corresponding adjustment, the errors (parallax) can be reduced by several orders of magnitude. Furthermore, correction values ​​are used during the alignment of the substrates to be bonded in order to further minimize the alignment errors of the substrates relative to each other.

[0048] Thus, the adjustment marks arranged above and below and the additional height information they provide advantageously allow the adjustment of the detection means without additional movements of the substrate holder, since each movement is superimposed with parasitic movements that can ultimately increase the alignment errors. Here, the measured positions of the adjustment marks and of the further adjustment marks (in another plane) are compared with the stored actual values. From the height difference and the deviation of the same height, a correctable positioning error can be determined.

[0049] In the adjustment marking field, preferably, a number of adjustment marks are arranged side by side in the respective plane, so that at least one first adjustment mark or at least one second adjustment mark of the corresponding plane can be detected. Furthermore, the adjustment marking field between the planes is preferably designed transparent to the detection means, so that the adjustment marks arranged above and below can be detected. It is also conceivable that the adjustment marks of the first plane are arranged offset with respect to the adjustment marks of the second plane, and that the adjustment marking fields have different steps.

[0050] The detection means can furthermore detect, in addition to the adjustment mark of a certain plane, further adjustment marks of this certain plane, if these are arranged in the focal region. The same applies for further planes. In this case, the detection means is preferably designed in such a way that it is possible to detect several adjustment marks of the respective plane, in particular adjustment marks arranged next to each other. This further increases the accuracy of the determination of the wedge error and makes it possible to adjust the detection means more effectively.

[0051] In another embodiment of the adjustment marking field, each adjustment mark can be implemented as a 3D structure with defined corners and / or edges, and each position feature is given a unique coding (information content), which allows a unique association of the corners and / or edges and / or steps to the 3D position information, allowing a complete spatial mapping of the substrate holder to the adjustment marking field.

[0052] Preferably, the alignment marks of the alignment marking field are detected at the position where the alignment markings of the substrate are to be positioned in a subsequent step. As a result of the positioning movements and adjustments and / or corrections, neither the substrate holder nor the at least one detection means need to be moved or repositioned. A fixed position allows for a high accuracy of the substrate alignment and thus for a high accuracy of bonding.

[0053] The detection unit preferably has a focusing means, preferably an objective lens, which focuses or sets the focus on the first adjustment mark during detection. In this case, the detection unit or the objective lens assumes a focus position in which the detection unit can detect a specific focus area. As a result, the adjustment mark arranged in the focus area, which is focused on the focus area of ​​the specific focus position of the detection unit or the objective lens, can be detected. During detection, preferably only the adjustment mark of the respective plane can be detected or distinguished, since the focus area of ​​the detection unit includes exactly one plane in each case. As a result, the distance between the first and second planes is preferably larger than the depth of the focus area, more preferably at least twice as large or larger.

[0054] For focusing, in particular for imaging multiple focal planes simultaneously, liquid lenses with variable curvature and / or fast switching, resonantly actuated liquid lenses can also be used. Similarly, changing the refractive index of the lenses is conceivable for focusing and / or refocusing. The listed approaches are equivalent or better technical solutions for typical focusing and / or refocusing by changing the spacing in the optical path.

[0055] Following the detection of the first adjustment mark in the first plane, the position of the detection means is fixed, in particular so that a focal region is determined, so that the detection unit can subsequently preferably only detect the adjustment mark in the determined focal region. The second plane is then detected by refocusing perpendicularly to the first plane of the adjustment marking field on the substrate holder surface of the substrate holder. The detection unit is moved at least until it can detect the second adjustment mark in the second plane of the adjustment marking field. In this respect, the focusing movement of the detection unit advantageously moves the detection unit by the distance required for focus setting.

[0056] This advantageously prevents alignment errors due to 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 alignment marks in the alignment marking field on the substrate holder, the angular error of the detection unit at the measured alignment marks can in particular be calculated by actual focusing movements and measurements.

[0057] For this purpose, the measured values, in particular the measured spacing, lateral displacement and / or twist of the different planes of the adjustment marks, are compared with stored ideal values ​​which are approximations of the respective true values, and the difference is used as a correction value for the further measurement values.

[0058] If further adjustment marks are arranged in further planes between the first and second planes, these can be measured by the detection unit during the focusing movement of the detection unit, so that the movement of the detection unit can be performed particularly accurately and controlled. Furthermore, due to the detected adjustment marks, the positions of which are known in the adjustment marking field, the relative alignment and the determination of the correction values ​​can be performed even more accurately.

[0059] The adjustment marks preferably have information about the respective location in the adjustment marking field. Here, in addition to the location along the adjustment marking field (xy location), the respective height or spacing of the planes is also known. As a result, when the first adjustment mark is detected, it can advantageously be determined in which plane it is located. In particular, if the adjustment marking field has three or more planes at different spacings from one another, this allows for easier open-loop or closed-loop control of the alignment and focusing, since the respective height information is detected for the adjustment marks. For example, during the successive detection during the movement or during the detection of the first adjustment mark, it can advantageously be determined which position of which plane or step in the focal area is detected. Furthermore, when a position is detected between two planes or steps, it is advantageously possible to approach a plane or step located above or below. Advantageously, the location in the xy position can also be detected and controlled.

[0060] The device is preferably configured in such a way that the focal position of the detection unit can be fixed immediately after detecting the first adjustment mark in the first plane of the adjustment marking field. The fixed focal position of the detection unit then determines the sharply imaged focal region. In this way, the distance of the first plane to the second plane can be advantageously approached by the movement device and thus focused. The detection unit is furthermore held in a fixed position, particularly laterally, so that the distance between the planes can be approached only by detecting the adjustment mark and by moving the detection means in the z-direction. This allows advantageously to verify the exact alignment of the detection means to the substrate holder by direct visual control by exactly one detection unit.

[0061] In one possible embodiment of the device for adjusting the detection means, at least one adjustment marking field is specified to be arranged on the back side of the substrate holder, facing away from the substrate holder surface. The adjustment marking field can be, for example, attached to the back side or embedded in the substrate holder. Furthermore, the adjustment marking field can be formed by the substrate holder itself. The detection unit can advantageously be arranged on the back side facing away from the substrate holder surface.

[0062] In a preferred embodiment of the device for adjusting the detection means, the center point of the adjustment marking field is determined to be at least partially aligned with the center point of the substrate holder surface. The central location of the adjustment marking field advantageously allows the adjustment of the detection means relative to the substrate holder to be advantageously accurate. This embodiment advantageously also allows linear error components or rotation of the detection unit relative to the substrate holder to be sensed.

[0063] Preferably, the adjustment marking field has at least three planes with adjustment marks. Here, the adjustment marks are provided with information on which plane they are located in. In this way, moreover, a number of specific intervals can be approached by the device, which allows a number of focus positions and thus a predefined interval between the detection means and the substrate holder to be set during the adjustment. The intervals between the planes can be of the same size. However, preferably, the planes are arranged with different intervals from one another. In this way, a number of intervals can be approached flexibly. The setting of different focus planes and thus different specific relative intervals between the detection means and the substrate holder can be advantageous in the case of different substrate thicknesses.

[0064] In a preferred embodiment of the device for adjusting the detection means, the device has at least one further adjustment marking field and at least one further detection unit for detecting the at least one further adjustment marking field, the at least one further adjustment marking field being specified as being arranged positionally fixed with respect to the substrate holder. A combination of several measurements for the further adjustment marking field allows for a more accurate alignment, since detection is performed at several points. For example, in this way, displacement and / or rotation errors can be identified. Here, the adjustment marking field and the at least one 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, which are each arranged distributed around a center point of the substrate holder surface, in particular evenly offset from one another in the radial direction.

[0065] The adjustment markings may be any objects that can be aligned with one another, for example crosses, circles or squares or propeller-like formations or grating structures, especially phase gratings for the spatial frequency domain, etc. Furthermore, 3D objects such as pyramids, cones, steps can be used as adjustment markings.

[0066] In one particularly advantageous embodiment of the device, the adjustment markings can at least partially comprise a QR code, which in particular represents an absolute machine-readable positional coding (x, y, z position) of the respective adjustment marking, thereby providing a complete mapping of the substrate holder and / or substrate holder surface with the adjustment marking fields before using the substrate holder, in order to use as reference values ​​for all adjustment processes.

[0067] In another particularly advantageous embodiment, the alignment markings may at least partially comprise alphanumeric symbols, which in particular represent the absolute, machine-readable positional coding (x, y, z position) of the respective alignment mark. The alphanumeric symbols are preferably also operator readable.

[0068] The modulating markings and / or modulating marking fields are preferably detected using electromagnetic beams of a certain wavelength and / or wavelength range. These include, for example, infrared beams, visible light or ultraviolet beams. It is likewise possible to use beams of shorter wavelengths, such as EUV (extreme ultraviolet beams) or X-ray beams.

[0069] This adjustment marking field therefore consists of or includes position-coded and height-coded adjustment markings, which provide unique position and height information of the substrate holder for adjustment of the detection means.

[0070] In one embodiment, the size or dimensions of the adjustment marking field in the xy direction are particularly adapted to the focal area of ​​the optical detection means, so that at least two steps or alignment mark planes, respectively, can be observed.

[0071] Here, the number of steps and the total height of the adjustment marking field are preferably adapted to the interval to be adjusted, for example, if a focusing interval of at least 500 micrometers is to be set, then preferably 550 micrometers of height-coded position information is mapped in the adjustment marking field, thereby allowing this interval to be uniquely approximated.

[0072] The detection is preferably performed by corresponding imaging optics, whereby the depth of field can be selected such that it is smaller than the step height or layer thickness of the adjustment marking field. The depth of field (English: depth of focus, DOF) is the region in the image space of the imaging optics in which a sufficiently sharp image of the focused object, in particular the alignment marking or adjustment marking, occurs. Conversely, this means that the image plane (image detection means, sensor) can be displaced in the region of the depth of field without the image of the object being significantly blurred.

[0073] When detection of the adjustment marks of the adjustment marking field is performed with a small depth of field, which is smaller than the step height, preferably smaller than half this step height, particularly preferably smaller than 0.1 x the step height, the position of the adjustment marking field can be uniquely identified, in particular in the z direction.

[0074] The depth of field of the detection means is less than 50 micrometers, preferably less than 20 micrometers, particularly preferably less than 10 micrometers, very particularly preferably less than 5 micrometers and in the most optimal case less than 4 micrometers.

[0075] On the other hand, if the depth of field is large and at least two step heights are sharply imaged, the positioning uncertainty of the device increases, since this does not allow a unique mapping of a z-height to one step.

[0076] In a preferred embodiment of the device, the image detection means or the detection means of the detection unit can be reproducibly shifted by 0.2× step height without refocusing on the image side. This can be used to determine which alignment mark of the adjustment marking field should be used for positioning when the focal plane on the image side is directly located at two adjacent step heights and the two steps are equally clearly visible. Small displacements of the image detection means allow the determination of the adjustment marking to be used (also as a computer-implemented independent method).

[0077] When detecting the adjustment markings, it is physically limited, in particular only one plane or step, respectively, is sharply imaged. In this respect, preferably only one step or step, respectively, is located in the focal area of ​​the detection unit. The adjustment markings of the adjustment marking field are position- and spatially coded, so that from the sharply detected adjustment marks of the plane, in particular position information of the substrate holder and / or the detection means in the spatial coordinate system can be determined. By refocusing the detection means on another adjustment marking, by the magnitude of the known step height and from the measured deviation of the same height of the adjustment mark, in particular an angular error of the detection means can be determined, which can be used as a correction value for the alignment of the substrate stack.

[0078] This method for adjustment increases the alignment accuracy, in particular by providing correction values ​​for local angular errors of the detection unit, which are detected by a separate adjustment marking field and a corresponding separate detection unit and used for open-loop and / or closed-loop control of the alignment.

[0079] For this purpose, the apparatus for conditioning and aligning a substrate and for bonding a substrate preferably comprises a control unit, in particular a software-assisted control unit, by means of which the steps described herein are carried out and the components are controlled, whereby a closed control loop and a closed loop control are to be understood as being included in the control unit.

[0080] By X-direction and Y-direction or X-position and Y-position is understood a direction extending or a position located in an XY coordinate system or in any Z-plane of the XY coordinate system. The Z-direction is located orthogonal to the XY-direction. The X-direction and Y-direction in particular preferably correspond to a lateral direction along the plane 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 focal position of the detection unit is fixed in the XY-plane.

[0081] The position characteristic is calculated or detected from position and / or location values ​​of the position markings on the substrate holder, in particular by detecting and evaluating this coordinate marking field.

[0082] The alignment marking field is preferably located near the alignment marking of the substrate. Particularly preferably, at least one alignment marking of the substrate and the adjustment marking field are arranged on the substrate holder so that they can be detected without laterally repositioning the detection means. An additional alignment marking field can also be arranged on the rear side of the substrate holder, which can be used both for adjusting the additional detection means and for aligning the substrate stack with the correlated position.

[0083] In one particularly preferred embodiment, at least one alignment marking field is preferably aligned in the z-direction to the additional alignment markings of the substrate, preferably on the rear surface of the substrate holder.

[0084] In another preferred embodiment of the apparatus, at least one alignment marking field is preferably provided on the backside of the substrate holder, aligned in the z-direction at the centre of the substrate or at a centre point of the substrate holder surface.

[0085] In another preferred embodiment of the apparatus, two alignment marking fields are preferably provided in respective alignment in the z-direction with the alignment markings of the substrate holder, in particular on the rear surface of the substrate holder.

[0086] In another preferred embodiment of the device, at least one adjustment marking field is provided on the substrate side of the substrate holder or on the substrate holder surface side in the vicinity of the substrate for optically detecting the accessible positions, which additional detection means can be aligned with respect to the substrate holder in a first method and can be used as additional detection means for aligning the substrate in a second method.

[0087] A further embodiment of the device comprises at least two adjustment marking fields on the substrate side of the substrate holder near the substrate edge for optically detecting the accessible positions, which advantageously allows the substrate holder to be leveled.

[0088] The method and the device for alignment in particular have at least one additional detection unit with a corresponding measuring system and / or closed-loop control system and at least one additional adjustment and / or alignment marking field, whereby the alignment accuracy is further increased by correlation of the additional measurement values ​​with at least one of the measurement values ​​of the additional detection unit, for which respective correction values ​​from a number of measurements are used.

[0089] In a subsequent step after adjusting the detection means using a correction, correlation of at least one of the measured additional alignment markings, in particular on the contact surfaces of the first and / or second substrate, with at least one alignment mark of the alignment marking field, which is also freely accessible and visible when aligning the substrates, allows direct observation of the alignment mark and thus real-time measurement and closed-loop control during alignment, which additionally increases the alignment accuracy of the substrates.

[0090] In another embodiment of the device, at least one further adjustment marking field is positioned on the substrate side of the substrate holder near the periphery of the substrate in a position that is permanently accessible to the further detection unit, particularly preferably with a surface of the adjustment marking field being arranged in the same plane as the surface to be bonded of the substrate fixed to the substrate holder.

[0091] The direct observation of the alignment markings on the substrate can be replaced by a direct observation of the alignment markings on the substrate holder due to additionally added 3D position features on the substrate holder, which can be uniquely correlated with the position features on the substrate. This has the advantage that an observable part of the substrate holder can be located substantially always in the field of view or detection area of ​​the detection unit. Due to the 3D position information and correction of the angular position of the detection means, the substrates can be aligned with each other with higher accuracy.

[0092] Preferably, the detection range of the detection unit is an area of ​​less than 3 mm×3 mm, preferably less than 2 mm×2 mm, particularly preferably less than 1 mm×1 mm.

[0093] Active feedback of data for positioning and position correction provides greater accuracy compared to open-loop controlled positioning in the prior art, since in a closed control loop the actual state of the position can be controlled.

[0094] A correlation is formed between the alignment marks of the first and / or second substrate on the respective contact surfaces of the substrates and at least one alignment mark of the alignment marking field, the one alignment mark of the alignment marking field being in particular directly detectable by the detection unit during alignment.

[0095] The direct detectability or observability of at least one additional alignment mark of the additional alignment marking field allows real-time measurement of the 3D position of the substrate holder or the detection means. The same device can be used to reduce alignment errors during substrate alignment or during bonding, in particular fusion bonding, of the substrate. In this case, the alignment accuracy is increased, since by detecting the alignment marking field and by providing correction values ​​and calculated height information, the positioning uncertainty is eliminated, which reduces error propagation. Such measures reduce the number of necessary feed movements and improve the alignment accuracy by closed-loop controlled height adjustment during bonding.

[0096] The detection unit for detecting the alignment marking fields is in particular part of an optical system for detecting the alignment marking fields and according to an advantageous embodiment comprises beam forming elements and / or deflection elements, in particular for Köhler illumination, e.g. mirrors, lenses, prisms, beam sources etc., as well as image detection means, e.g. cameras etc. (CMOS sensors or CCDs, or surface detection means or line detection means or point detection means, e.g. phototransistors etc.), movement means for focusing and evaluation means for closed-loop control of the optical system.

[0097] In another embodiment of the device, the optical system can be used in combination with a rotation system for substrate positioning according to the turn-over adjustment method (see Friedrich Hansen's Justierung, VEB Verlag Technik, 1964, section 6.2.4, Umschlagmethode). Thus, during a turn-over adjustment, at least one measurement is carried out in a given position of the respective substrate holder and at least one measurement in a position rotated by 180 degrees, facing in the opposite direction and turned over. The measurement results thus obtained are in particular free of eccentricity errors. In this case, the substrate holder can preferably be rotated, while the detection means remain in a fixed position except for focusing.

[0098] A development of the device for adjustment can be used as a device for aligning substrates.

[0099] The device may further comprise a system for producing a pre-bond. For this purpose, pressure pins and / or configurable nozzles can be used for joining the substrates to initiate the fusion bond. In particular, the configurable nozzles may be height-configurable, so that their relative position with respect to the rear surface of the substrate can be changed, and the volumetric flow rate of the nozzles can be changed in a closed-loop controlled manner. The alignment of these nozzles can advantageously be performed on the basis of adjustment markings arranged above and below.

[0100] Furthermore, the apparatus preferably includes a movement device with a drive system, a guide system, a holding part and a measurement system for moving, positioning and accurately aligning at least the detection unit and the substrate holder and thus the substrate to be aligned.

[0101] These movement devices can generate respective movements as a result of individual movements, whereby the movement devices can preferably include a high speed coarse positioning device that does not meet the accuracy requirements, and a fine positioning device that operates accurately.

[0102] A positioning device is understood to be a coarse positioning device if, over the entire travel path or rotation range of the rotatable rotary drive, one revolution of which is 360 degrees, the approach accuracy and / or repeatability accuracy deviates from the target value by more than 0.1%, preferably by more than 0.05%, particularly preferably by more than 0.01%.

[0103] Thus, for example, a coarse positioner having a travel distance of over 600mm (twice the substrate diameter) would result in a residual uncertainty of 600mm x 0.01% close accuracy, i.e. better than 60 micrometers.

[0104] In another embodiment of the coarse positioning, the residual uncertainty of the approach or repeatability is less than 100 micrometers, preferably less than 50 micrometers, particularly preferably less than 10 micrometers, whereby thermal disturbances should likewise be taken into account.

[0105] The coarse positioning device performs its positioning function with sufficient accuracy only if there is a deviation in the movement range of the corresponding fine positioning device between the actual position actually reached and the target value of this position.

[0106] The alternative coarse positioning device performs its positioning function with sufficient accuracy only if there is a deviation between the actual position actually reached and the target value of this position of half the movement range of the corresponding fine positioning device.

[0107] A positioning device is understood to be a fine positioning device when, over the entire travel path or rotation range, the residual uncertainty in approach accuracy and / or repeatability is less than 500 ppb from the target value, preferably less than 100 ppb, and more preferably not more than 1 ppb.

[0108] Advantageously, the fine positioning device is capable of compensating for absolute positioning errors of less than 5 micrometers, preferably less than 1 micrometer.

[0109] The substrates may be aligned relative to one another in all six degrees of freedom of movement, i.e. three translational movements in the coordinate directions x, y and z and three rotational movements about the coordinate directions, whereby movements can be made in any direction and orientation.

[0110] A robot for handling the substrate is included in the transfer device. The holder may be structurally or functionally integrated in the transfer device.

[0111] Furthermore, the device for adjusting the detection unit preferably comprises a closed-loop control system and / or an evaluation system, in particular a calculator, for carrying out the described steps, in particular the movement flows, for making corrections and for analysing and storing the operating state of the device.

[0112] The procedures are preferably written as recipes and implemented in a machine-readable form. A recipe is a collection of optimal values ​​of functionally or process-technologically relevant parameters. By using recipes, the reproducibility of the manufacturing flow can be guaranteed.

[0113] According to an advantageous embodiment, the regulating device further comprises a power supply system and auxiliary and / or supplementary systems (compressed air, vacuum, electrical energy, fluids such as hydraulic pressure, coolants, heat transfer media, means and / or devices for temperature stabilization, electromagnetic shielding).

[0114] The alignment apparatus may further include a frame, housing, active or passive subsystems that inhibit vibration or that dampen or eliminate vibration.

[0115] The alignment device preferably further comprises at least one measuring system, which preferably comprises a measuring unit for each axis of movement, which can in particular be implemented as a displacement measuring system and / or an angle measuring system, and which preferably comprises at least one detection unit or an additional detection unit.

[0116] Tactile or probe-based measurement methods can be used, as well as non-tactile measurement methods. The measurement standard, the measurement unit, can be present in a physical, material object, in particular a scale, or can be implicit in the measurement method, such as the wavelength of the beam used.

[0117] To achieve the alignment accuracy, at least one of the following measurement systems can be selected and used: Guidance system, and / or Volumetric method, and / or Resistance method, and / or Comparison methods, in particular optical image recognition methods, detection of position marks and / or QR codes, and / or Incremental or absolute (especially with glass standards as scales or with interferometers, especially laser interferometers, and also with magnetic standards), and / or Time of flight measurements (Doppler, time of flight) or other time detection methods, and / or Triangulation methods, in particular laser triangulation, and / or Autofocus methods, and / or · Strength measurement methods such as optical fiber distance meters can be used.

[0118] In particular, the described measuring methods can be used additionally in the adjustment device, not only to detect and correct the local relative position and / or location of the detection means with respect to the substrate holder, but also to perform absolute position measurements in the device.

[0119] A particularly preferred embodiment of the apparatus for alignment further comprises at least one measuring system for detecting at least one XYZ position and / or alignment point and / or angular position of the substrate and / or the substrate holder relative to a predefined reference, in particular a frame, the measuring system comprising at least one adjusted detection unit.

[0120] Here, the 3D position of the substrate holder, preferably with a corrected angular position, is determined by the measuring system or by a detection unit of the measuring system, so that height information and tilt can be determined for the same height position information from the measurement. For this purpose, at least one alignment marking field consisting of steps and / or layers with unique position markings is detected.

[0121] A frame may in particular be understood as a part made of natural hard stone or mineral cast or spheroidal graphite cast or hydraulic concrete, which is formed in particular in a vibration-damping and / or vibration-proof and / or vibration-eliminating manner.

[0122] The idea can likewise be advantageously reversed by mounting the detection unit on the substrate holder and the adjusting marking field on, for example, a frame, in which case the detection unit is moved together with the substrate holder and the adjusting marking field is fixed to the frame.

[0123] In order to be able to carry out detection, evaluation and open-loop control at any time, in particular continuously, the adjustment marks of the adjustment marking field are distributed in accordance with an advantageous embodiment over a respective planar area larger than the field of view of the image detection system of the detection unit, so that the open-loop control unit (and / or the closed-loop control unit) is supplied with particularly continuous measured values. Here, however, for each position in the field of view of the image detection system, the adjustment marks of the adjustment marking field are designed in such a way that height information can be determined from the adjustment marking field and / or from the extended same height position information. In other words, at each lateral position of the substrate holder, the arrangement of the adjustment markings of the adjustment marking field allows the spatial position of the detection means to be determined and a correction of the angular position to be determined. In particular, the relative positions of the detection means are present as 3D position information, so that a more precise spatial alignment of the substrates fixed thereon with respect to each other can be carried out.

[0124] For the determination of the XYZ position, the device for alignment can additionally use at least one detection means at least one correspondingly configured three-beam interferometer, in particular with a monolithic reflector, for determining the XYZ position and / or for determining the location of the substrate holder. Structurally for this, the detection means and the interferometer are integrated into an assembly, so that the detection means and the interferometer do not move independently of one another.

[0125] In another advantageous embodiment of the device, in addition to the device for detecting the alignment marks of the alignment marking field, a measuring means, for example a monolithic reflector in the form of a prism, can additionally be included, which is measured by a plurality of, in particular three-beam interferometers. In this way, by averaging, forming a difference and forming a measurement sequence, the propagation of errors can be eliminated and the alignment accuracy can be further increased. In other words, a sufficiently fast position measurement allows the use of a closed-loop control system for the trajectory of the movement, which further reduces the position error of the substrate holder.

[0126] The alignment and / or adjustment device, in particular the substrate holder formed from a monolithic block, preferably has at least two of the following functions: Fixation of the substrate by vacuum (vacuum tracks, connections) and / or by electrostatic means, geometric compensation of deformations of the substrate by means of mechanical and / or hydraulic and / or piezoelectric and / or pyroelectric and / or electrothermal actuating elements, Positioning and / or localization (measuring references, reflecting surfaces and / or prisms, in particular reflectors for interferometry, registration marks and / or registration mark fields, measuring references for surface-shaped planes, volumetric references, in particular steps, layer systems of known layer height with adjustment markings divided into planes) with movement (guide tracks).

[0127] In particular, the displacement devices not used for the fine adjustment are preferably configured as robot systems with incremental displacement sensors, and the precision of these displacement devices for the auxiliary movements is decoupled from the precision for the alignment of the substrate stack, so that the auxiliary movements are performed with a low repeatability precision of less than 1 mm, preferably less than 500 micrometers, particularly preferably less than 150 micrometers.

[0128] The open-loop and / or closed-loop control of the movement device of the alignment device for (lateral) alignment (fine-tuning) is carried out in particular on the basis of the detected XYZ positions and / or alignment points. For this purpose, the additional alignment marks of the substrate are correlated in the field of view of the surface of the substrate holder with the alignment marks of the alignment marking field, which are uniquely associated with them. The height information and the angular position as well as the corrections thereof are calculated from the alignment markings of the alignment marking field. This results in an XYZ position and a spatial orientation, which can be continuously observed in particular during the feed movement of the alignment and during the setting of the gap for bonding and can be used in real time, in particular for error correction of the feed movement.

[0129] The accuracy of the displacement device for the alignment is less than 500 nm, preferably less than 100 nm, particularly preferably less than 50 nm, very particularly preferably less than 10 nm, more preferably less than 5 nm and most preferably less than 1 nm.

[0130] In particularly preferred embodiments of the device, the error in the alignment accuracy of the device is less than 20%, preferably less than 10%, most preferably less than 1% of the maximum allowable alignment error.

[0131] In other words, if the tolerable alignment error of the substrate is, for example, 10 nm, the positioning error is a maximum of 20% of the value, ie 2 nm.

[0132] In a particularly preferred embodiment of the substrate holder, the substrate holder may be constructed from a number of components as a non-monolithic body. The substrate placement surface comprises at least one alignment marking field with alignment markings and, in particular, distributed point-like placements for placement of the substrate. The substrate placement surface forms part of an insert, which is a reproducibly elastically deformable body. The insert is accommodated in the base in a particularly statically determined manner. The substrate placement surface is fluidically connected, in particular to a vacuum, through correspondingly formed passages and nozzles and supply lines, which negative pressure can also be replaced by a positive pressure.

[0133] The insert is clamped in the base body. At least the rear surface of the insert, which faces away from the front surface of the substrate holder, is in particular accommodated in an airtight manner in a separated manner in the base body of the substrate holder, so that the insert can be reproducibly deformed by vacuum or positive pressure.

[0134] The fluid connections between the substrate holder body cavity and the backside of the insert can be independently supplied with closed-loop controlled positive or negative pressure, which causes deformation of the insert.

[0135] An exemplary embodiment of the method for adjusting the detection means is carried out in particular in the following order, in particular in the following steps:

[0136] First step: moving at least one detection means to an expected position of an alignment marking of a substrate to be aligned, said positioning being subject to a positioning uncertainty.

[0137] Second step: The substrate holder is fixed so that no movement of the substrate holder occurs.

[0138] Third step: focusing a detection means on the alignment marking of the alignment marking field to detect the alignment marking.

[0139] Fourth step: retrieving the stored positions of the alignment markings from the knowledge store and / or database and correlating them with the detected measurements of the detection means, thereby storing the spatial positions, in particular the absolute positions, of the detected alignment markings.

[0140] Fifth step: focusing the detection means on a further alignment marking in a second plane of the alignment markings, the device preferably only performing a focusing movement in the z direction.

[0141] Sixth step: Detect another alignment mark and calculate the position and location of the another alignment marking.

[0142] Seventh step: Calculate the relative and / or angular position of the detection means with respect to the local normal direction of the substrate holder from the known height, in particular from the storage device, and the calculated focusing height, as well as from the xy lateral displacements of the further adjustment markings. This value can be used as a correction value for the subsequent steps.

[0143] In one advantageous embodiment, the located adjustment marking is detectable within a radius of less than 3 millimeters, preferably less than 2 millimeters, particularly preferably less than 1 millimeter, very particularly preferably less than 500 micrometers, and even more preferably less than 250 micrometers around the optical axis of the respective objective lens of the detection unit.

[0144] A measuring system with at least one detection unit (especially a measuring microscope with an objective lens) for detecting the adjustment marks of the adjustment marking field detects the first adjustment mark in the first plane and thus the XYZ position and / or alignment point of the substrate holder, while the substrate holder is fixed and the position of the additional alignment marking of the substrate below is correlated to the detected position. To detect the position of the substrate holder, an adjustment marking field is used that is arranged in a fixed position relative to the substrate holder.

[0145] Preferably, a step in the coordinated marking field is focused on and detected, where the step is located near an exposed surface of the coordinated marking field and the coordinated marking is observable throughout the entire depth of the coordinated marking field.

[0146] In this focus position, the focus position of the detection unit and thus the focus area (in particular of the objective lens) are fixed in order to detect the adjustment marking field. The detection unit is furthermore in particular locally fixed or held in a fixed position.

[0147] During refocusing, at the initial position, at least one alignment mark in the first plane is detected, and at the target position, at least one alignment mark in the second plane of the alignment marking field is detected.

[0148] The measured positional and / or angular errors are used to correct the position of the substrate holder at least in the lateral plane by moving the detection means so that the corresponding at least one second alignment mark in the second plane is focused on or is located within the focal area of ​​the detection unit, such that the visual control can ensure that a sufficiently accurate approach to the spacing between the first and second planes has been achieved.

[0149] This allows the use of correction values ​​so that a repositioning of the substrate holder can be omitted and alignment errors can be avoided. The adjustment marking fields provide height information. When aligning the substrates with respect to one another, corrections can be made in the relative positions of the substrates if the alignment errors exceed the determined boundary values. For such corrections, the adjustment method provides correction values.

[0150] The alignment errors for which the correction is applicable are for displacements of 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.

[0151] The alignment error applicable for correction for twist is less than 50 microradians, preferably less than 10 microradians, particularly preferably less than 5 microradians, very particularly preferably less than 1 microradian, even more preferably less than 0.1 microradians and most preferably less than 0.05 microradians.

[0152] In other words, the method allows measuring different planes of the adjustment marking field according to a sequence of predetermined relative movements, whereby the relative positions and / or alignment points of the two measured objects to be derived from this, thereby forming correction values ​​that further increase the alignment accuracy of the substrate stack.

[0153] If the observation plane of the adjustment marking field is not normal to at least one z-axis of the detection means, the respective relative movement will result in displacements and / or angular errors in the xy-plane (yaw errors and / or pitch errors and / or roll errors), which are detectable and correspondingly correctable.

[0154] In particular, the substrate holder with the integrated adjustment marking field can be understood as an independent device. The substrate holder preferably includes at least one adjustment marking field and is arranged near and below the substrate mounting surface of the substrate holder such that no contact occurs between the substrate and the adjustment mark when the substrate holder is used. In other words, the adjustment marking of the adjustment marking field and the substrate do not come into contact at any time when the substrate is placed on the substrate holder surface. Particularly advantageous is the use of a protruding specimen holder with an integrated adjustment marking field.

[0155] In an advantageous embodiment of the substrate holder, the individual adjustment marks of the adjustment marking field can be arranged on the substrate holder, which are located on the substrate around the alignment marks. The purpose of this arrangement is to calibrate and / or adjust the device by means of the detection means without a substrate, and in particular to measure the angular errors of the individual detection means, in order to be able to use the calibration values ​​of the device during alignment. Preferably after calibration, the detection means are locked and fixed in this position. This allows the adjustment marks of the substrate to be detected without a readjustment movement of the detection means when the substrate holder is used for aligning the substrate. In other words, in particular the z-axis of the alignment marks of the alignment marking field coincides locally with the z-axis of the alignment marks of the substrate in the field of view of the individual detection means. This allows the calibrated detection means and the substrate holder to be used for aligning the substrate without repositioning.

[0156] The concepts of coincidence of axes, or congruence or parallelism or perpendicularity, are used in this disclosure as concepts of quantities with tolerances, whereby tolerances apply to non-tolerated linear or angular dimensions according to ISO 2768, unless specifically these tolerances are explicitly stated. [Brief description of the drawings]

[0157] Further advantages, features and details of the invention will become apparent from the following description of preferred embodiments and on the basis of the drawings, which diagrammatically show: [Figure 1] FIG. 2 is a cross-sectional view of one embodiment of an apparatus for adjusting a detection means. [Figure 2a] FIG. 2 is a plan view of an exemplary arrangement of alignment marks or alignment marking fields between raised portions of a substrate holder; [Figure 2b] FIG. 2 is a cross-sectional view of one embodiment of a coordinated marking field. [Diagram 3] FIG. 2 is a plan view of one embodiment of a coordinate marking field with coordinate marks. [Figure 4] FIG. 2 is a cross-sectional view of one embodiment of a coordinated marking field with a detection unit. [Figure 5a] FIG. 2 shows the detection unit in a first position. [Figure 5b] FIG. 2 shows the detection unit in a second position.

[0158] The advantages and features of the present invention are illustrated in the drawings, in which the illustrated embodiments are labeled with reference numbers, and the same reference numbers are used for individual components or features that have the same or similarly functioning functions.

[0159] A schematic functional diagram of an apparatus for adjusting detection means is depicted in Fig. 1. The apparatus is part of an alignment installation 1 for aligning or processing substrates. The alignment installation 1 can align substrates (not shown) with one another and at least partially and / or temporarily (so-called pre-bonding) bond them to one another.

[0160] The alignment facility 1 comprises a first substrate holder 9, on whose substrate holder surface a first substrate can be loaded and fixed, and further comprises a second substrate holder 11, on whose substrate holder surface a second substrate can be loaded and fixed.

[0161] In particular the lower first substrate holder 9 is arranged on a first movement device 10 for holding the first substrate holder 9 and for carrying out a feeding movement and an adjustment movement (alignment). In particular the upper second substrate holder 11 is arranged on a second movement device 12 for holding the second substrate holder 11 and for carrying out a feeding movement and an adjustment movement (alignment). The movement devices 10, 12 are fixed to a common rigid table or frame 8 in order to reduce / minimize vibrations of the functional components. The frame may in particular include active vibration dampers.

[0162] The optical system 2, 5 of the alignment facility 1 can likewise be used to detect alignment markings on a substrate (not shown). By means of the detection means 3, 6 (in particular the optical system) alignment markings on the substrate or on the substrate holder can thus also be detected. This optical system 2 is primarily configured to detect alignment marks of the alignment marking field.

[0163] The optical system 2, in particular the detection means 3, can be focused in a focal plane or focal position. At least one adjustment mark can be detected here in the focal region 19. The horizontal spacing (z-direction) between the adjustment marks in different planes of the adjustment marking field is known and can additionally be read out based on the information content of the adjustment marking (e.g. QR code). The movement of the optical system 2, in particular in the X-, Y- and Z-directions, is effected by a positioning device 4 for positioning the optical system 2. The positioning device 4 can in particular be fixed to a robust frame 8.

[0164] If this optical system 2 is an optical measuring system 2, the positioning device 4 can focus by moving the detection unit 3 in the Z direction on the adjustment marks in the first plane 18 of the adjustment marking field 14. Positioning in the XY direction is also conceivable, with preferably fixation on a table / frame in particular during adjustment.

[0165] In the illustrated embodiment of the alignment installation 1 with the detection unit 3, the alignment marks 15 of the alignment marking field 14 can furthermore be detected at the xyz positions. After refocusing or refocusing to another plane (the distance between the planes of the alignment marking field 14 is now known), the actual spatial angular position is determined from the known height of the planes or from the known spacing between the planes of the alignment marking field and from the parasitic lateral movement of the detection means 3 with the substrate holder 9 fixed. This allows the wedge error of the optical system 3 and the substrate holder 9 or of the receiving surface of the substrate holder 9 to be determined. The optical system 3 can thus advantageously be adjusted or calibrated relative to the substrate holder 9 on the basis of the alignment marking field. Furthermore, the position of the detection means 3 can also be calculated. This position can be used as a correction factor for reducing the alignment errors of the substrate stack. The substrate, not shown, is in particular received on a substrate holder surface 20, which is made up of a number of individual surfaces. The substrate receiving surface 20 preferably comprises a number of projections 21.

[0166] In the illustrated embodiment of the alignment apparatus 1, moreover, the measuring system 5 or detection unit 6 makes it possible in particular to detect the XY position and / or orientation (in particular also the rotational orientation) and / or height position of the underlying substrate holder 9 with particularly high precision.

[0167] To initiate fusion bonding, a preload can be applied to at least the upper substrate by the substrate preload device 13. The preload can be achieved by mechanical preloading with preload elements, so-called bonding pins. In another embodiment of the substrate preload device, the substrate can be preloaded by a fluid, in particular a gas from a nozzle, in particular a movable nozzle.

[0168] A preferred embodiment, not shown, of the device makes it possible to carry out the following steps, given by way of example only: The first substrate is fixed on the substrate holder surface of the first substrate holder 9. In particular, mechanical and / or electrostatic clamps, a pressing force formed due to a pressure difference between the ambient environment of normal atmosphere and the negative pressure in the first substrate holder 9, also called vacuum fixing, are used as the fixing. This fixing is performed in particular in such a way that the first substrate is prevented from undergoing incorrect or undesired movements relative to the first substrate holder 9 during the entire process. In particular, if the first substrate holder 9 and the first substrate each have corresponding, preferably linearly corresponding, thermal expansion coefficients, the thermal expansion can be prevented or reduced, the difference in the thermal expansion coefficients and / or the linear course of the thermal expansion coefficients being preferably less than 5%, preferably less than 3%, particularly preferably less than 1%.

[0169] The equipment is preferably operated in a temperature stabilized ambient environment, in particular a clean room, in which the temperature fluctuations during the adjustment or alignment cycles are 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.

[0170] The fixed first substrate and in particular the insert of the substrate holder 9 can be understood as a quasi-monolithic body for the movement of the first substrate, which cannot move relative to one another.

[0171] This substrate fixing can be effected by form-locking and / or preferably by force-locking. The quasi-monolithic joining ensures that influences which can cause displacements and / or twists and / or deformations between the substrate holder and the substrate are at least reduced, preferably reduced by at least an order of magnitude, particularly preferably eliminated. Thus, together with the adjustment of the detection means 3 to the substrate holder, alignment errors can be further reduced.

[0172] The substrate and the substrate holder 9 can be joined by a positive or force connection, in particular in such a way that differential thermal expansions can be suppressed. Furthermore, the substrate holder can reduce, eliminate and / or correct independent deformations of the substrate. In addition to these measures, at least one detection means is provided in a defined position and angular position relative to the substrate holder, in particular relative to the adjustment marking of the adjustment marking field on the substrate holder surface, so that on the one hand slow thermal relative movements can be detected and corrected, and on the other hand positional errors of the substrate holder relative to the detection means can at least be reduced by preadjusting the position and angular position of the detection means.

[0173] In one embodiment, both the lower substrate holder 9 and the upper substrate holder 11 may include additional, passively and / or actively actuated deformation elements and / or intermediate plates, also referred to as inserts, which minimize the mechanical and / or thermal properties of the substrates in order to reduce residual alignment errors after bonding.

[0174] The first substrate holder 9 may be located in the optical path of the detection unit 3 during detection of the first alignment mark 15 of the alignment marking field 14 .

[0175] Preferably the detection unit, or equivalent detection means, is arranged aligned or perpendicular to a predefined alignment mark of the alignment marking field 14, so that detection of the alignment markings of the substrates to be bonded at the same xy position does not require repositioning of the substrate holder and / or detection means, thereby increasing the alignment accuracy of the substrate stack by reducing the required movements and detections and adjustments.

[0176] The lower substrate holder has alignment marks 15 of an alignment marking field 14. Based on the alignment marks 15, the XYZ position and the alignment point of the respective alignment mark 15 in the alignment marking field can be determined. By detecting further alignment marks 15 in other planes of the same alignment marking field 14, the wedge error or the angular position of the substrate holder 9 relative to the detection means 3 can then be determined.

[0177] For this purpose it is conceivable that instead of a relative movement (or refocusing) of the detection means 3, the substrate holder 9 is moved relative to it in the Z direction and the detection means is fixed. From this adjustment process analogous correction values ​​of the relative position can be calculated which in particular identify the parasitic movements of the substrate holder with respect to the fixed detection means.

[0178] In this case, if the substrate holder is transparent to the detection unit 6 , the detection unit 6 can also be used to detect the alignment marks 15 in different planes of the alignment marking field 14 .

[0179] The measurements (XY position and / or alignment location of the first substrate and XYZ position and / or alignment location of the first substrate holder 9 or the first substrate) can be correlated with each other after applying adjustments / corrections, so that the XYZ positions of the substrate holder 9 and / or the detection means can be reproducibly restored. This allows a closed-loop controlled movement of the substrate fixed on the substrate holder 9 for alignment and for setting the bonding spacing, without directly observing the adjustment markings 15 of the substrate holder 9 or the alignment markings of the substrate.

[0180] By correlating the positions of the substrates with the spatial positions and / or points of the substrate holder 9 or the detection means 3, alignment can be realized without directly observing the XYZ positions and / or alignment points and / or relative angular positions of the respective substrates during alignment and / or contact. The determined correction values ​​increase the positioning accuracy by reducing the positioning uncertainty before or during the alignment and contact of the first and second substrate. Furthermore, the spacing between the substrates can be set in a defined manner and / or minimized during alignment, for which additional adjustment marking fields can be used, in particular on the back side of the substrate holder facing away from the substrate receiving surface.

[0181] In particular, a positioning repeatability, also known as backlash (measured as the relative alignment error between two substrates), of less than 500 nm, preferably less than 100 nm, particularly preferably 30 nm, very particularly preferably 10 nm, even more preferably less than 5 nm and most preferably 1 nm is achieved.

[0182] This backlash results from the movement of the moving device, but only the detection location changes, so that the measurement quantity exists as a relative alignment error. The method reduces the local positioning inaccuracy by locally measuring the incorrect position of the detection means 3, so that due to this reduced accuracy of the local positioning inaccuracy the local alignment error is further reduced.

[0183] To further increase the alignment accuracy, the first detection unit 3 can be operated in time synchronization with at least one further additional detection unit 6. Here, the time difference between the detection of the measured values ​​is less than 3 seconds, preferably less than 1 second, particularly preferably less than 500 milliseconds, particularly very preferably less than 100 milliseconds, even more preferably preferably less than 10 milliseconds, most preferably less than 1 millisecond, and in the ideal case simultaneously. This is particularly advantageous, since the action of disturbing influences, such as mechanical vibrations, can be eliminated. Mechanical vibrations propagate in the material, especially with structure-borne sound at several thousand m / s. If the closed-loop control and detection means operate faster than the propagation speed of the structure-borne sound, the disturbances are reduced or eliminated.

[0184] If the detection unit 3 and the detection unit 6 are synchronized with each other (especially by simultaneous triggering of the detection and by adjusting the detection time and / or the same integration time for the camera system) for detecting the alignment marking field 14 and the further alignment marking on the back side of the substrate holder, some disturbing influences can be reduced and in the best case eliminated, since the detection should be performed at a time when disturbing influences have the smallest possible influence on the detection accuracy.

[0185] In a preferred embodiment of the method and device for adjusting the detection means, and in the device for adjustment, the detection is carried out synchronously, in particular at the peaks of vibration, especially if periodic disturbing influences are known. For this purpose, vibration sensors (accelerometers, interferometers, vibrometers) can be advantageously pre-mounted at the points of the device that are relevant for the accuracy. Disturbing influences are recorded by these vibration sensors and are taken into account or processed by calculation for elimination. In another embodiment, vibration sensors can be fixedly integrated at characteristic points of the installation.

[0186] It is advantageous for adjusting the detection means or possibly a number of detection means if the adjustment marking field 14 is completely measured and setpoint values ​​are provided in the storage device for comparison or difference formation. These setpoint values ​​in particular contain image data of the adjustment marks of the adjustment marking field 14 of the first substrate holder 9 and / or closed-loop control parameters, such as trajectories for optimally approaching a spatial position and / or machine-readable values, in particular for the drive, in particular for the focusing of the detection means approach 3. In other words, the locations of the individual adjustment marks of one adjustment marking field and of the other adjustment marks of another adjustment marking field are known and stored.

[0187] FIG. 2a shows a number of coordinate marking fields in a schematic, greatly enlarged plan view with one exemplary selected and visible coordinate mark 15 or coordinate marking 15 in each case.

[0188] The individual alignment marks 15 represent, symbolically and generally, an absolute and unique coding of the position and location of each individual alignment mark or alignment marking 15. The individual alignment marks 15 or alignment markings 15 may be provided in different planes of the alignment marking field. Since the xyz position of the respective alignment marking 15 is known, it is sufficient to detect the coded alignment marks 15 or alignment markings 15 for detecting the position of the substrate holder (not shown). This allows a refocusing (or a relative movement in the z direction with the same focus) on another alignment mark or alignment marking of the same alignment marking field, so that the angular position / wedge error of the detection means relative to the substrate holder can be determined. The adjustment of the detection means can therefore advantageously be performed on the basis of the alignment marking field.

[0189] FIG. 2b shows a coordinated marking field 14'' with different layers 16, 16' or stages. Thus, the coordinated marks of one stage are disposed in one plane and have a specific and known distance to the other stage or plane of the coordinated marking stage field 14''. In the illustrated embodiment, the coordinated marking field 14'' is disposed between ridges or protrusions 21'.

[0190] The adjustment marking fields 14'' are arranged in a fixed position relative to the substrate holder or substrate holder surface 20. Here, the mounting surface of the raised portion 21' (for receiving the substrate) is higher than the highest point of the adjustment marking field 14'' or has a larger distance to the substrate holder surface. The adjustment marking fields are therefore arranged below the substrate holder receiving surface (mounting surface of the raised portion). As a result, the adjustment marks or adjustment markings (in the uppermost plane of the respective adjustment marking field) advantageously do not come into contact with the substrate.

[0191] The reduced support surface of the protrusions 21' ensures that the substrate does not rest all over, which prevents possible distortion due to particles present on the backside of the substrate, thereby advantageously minimizing cross-contamination of the substrate or substrate holder.

[0192] The adjustment marking fields are arranged in a positionally fixed manner with respect to the substrate holder. In particular, the adjustment marks are located side by side in the field of view or focal area of ​​the detection unit 3 in different planes or steps and / or layers 16, 16' and are therefore detectable. Due to the known step heights or known spacing between the planes and the known positions of the adjustment markings, these can be used to determine the angular error of the refocused detection means.

[0193] To determine the correction values ​​from the position and angular position of the detection means, it is possible to use a modified method in which the layers 16 and 16' of the adjustment marking field 14'' are measured in particular by the following steps in the following order: In a first step, the substrate holder is lifted in the z direction by the substrate thickness. In a second step, at least one detection means 3 is moved to the expected xy position of the substrate alignment mark and fixed in the xy position. In a third step, at least one detection means is focused on the alignment markings of the alignment marking field 14 of the substrate holder and the alignment markings in the xy position and the rotation around the z axis are detected. In a fourth step, the substrate holder is moved away from the fixed detection means in the z direction, so that another alignment mark of another plane or layer 16 or 16' can be detected. In a fifth step, the alignment markings of the corresponding layer 16 or 16' and the relative displacement are determined from the substrate holder movement and the parasitic movement and compared with the ideal value to calculate a correction value. Here, a correction value is calculated for the inclination of the relative point between the substrate holder and the detection means. The detection means are then adjusted or the wedge error is compensated for.

[0194] The distance between the planes is 1 micrometer to 300 micrometers, preferably 5 micrometers to 200 micrometers, more preferably 10 micrometers to 100 micrometers, particularly preferably 25 micrometers to 75 micrometers, and most preferably 48 micrometers to 52 micrometers. For example, the distance between the planes is 50.00 micrometers.

[0195] Furthermore, it is advantageous if each additional alignment mark 15, 15' has detectable location information. A number of alignment fields between the ridges / protrusions 21, 21' make it possible to determine the angular position or wedge error between the substrate holder and the detection means at a corresponding number of locations without the need to move the detection means in the xy direction. Since the location of the respective detected alignment mark 15, 15' relative to the alignment mark 15 of the alignment marking field is known, this position and location information can be used for optimizing the movement or for setting the spacing, in particular the bonding gap. Advantageously, not only the location of the detected alignment mark 15, 15' relative to the alignment mark 15, 15' of the same plane is known, but also the respective planar location of the detected alignment mark 15, 15' relative to another plane of the alignment marking field.

[0196] FIG. 3 shows part of one possible embodiment of the coordination marking field 14″, where each exemplary coordination mark 15′ is supplemented with a machine-readable code. Here, the individual coordination marks 15 may be arranged in different planes (steps and / or layers) and the code may include information about which plane each one is in. Furthermore, the code may include unique information about the position and location of each coordination mark 15′.

[0197] FIG. 4 shows an embodiment of the adjustment marking field 14'''' in a cross-sectional view. The adjustment marks 15' of the adjustment marking field 14'''' are arranged in three different planes 18, 18', 18'' and can be detected by the detection unit 3. Here, the detection unit 3 can only detect the adjustment marks 15' in the focal area 19. It is also conceivable that the detection unit 3 uses electromagnetic beams of different wavelengths to detect adjustment markings arranged above and below the different planes. In this case, the adjustment marking field is correspondingly at least partially transparent to these different wavelengths.

[0198] The first plane 18 has a known distance 17'' relative to the second plane 18'. The second plane 18' has a similarly known distance 17' relative to the third plane 18''. Furthermore, the distance 17 between the first plane 18 and the third plane 18'' is known. The distances 17'' and 17' are of different magnitudes in the illustrated embodiment, so that all three distances 17, 17', 17', respectively, can be approximated or set when using the adjustment marking field 14'''' for adjustment of the detection means. This allows different distances between the detection means 3 and the adjustment markings to be detected. At the same time, known distances relative to the other planes can be advantageously approximated.

[0199] The combination of the distances 17, 17', 17'' can also be approached by multiple movements of the fixed-position substrate plate holder 9 relative to the adjustment marking field 14''', which movements can be carried out as focusing movements of the detection means 3. For example, the focused distance 17'' can first be set and then the distance 17' can be approached further in the same direction. It is also possible, for example, to move the substrate holder by twice the distance 17''. For this, the alignment is performed in two steps and the detection unit is correspondingly set during these steps, since the focal position of the detection unit 3 and thus the focal area 19 are adapted to the detection unit 3.

[0200] In figures 5a and 5b the optical system 3 is shown in a first position 23 and in a second position 24 (after adjustment). A wedge error (angle 22) between the optical system 3 and the substrate holder, i.e. an angular error between the optical axis 25 of the optical system 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 optical system 3 is therefore advantageously adjustable based on detection of two adjustment markings in the different planes 18, 18', 18''. [Explanation of symbols]

[0201] 1. Alignment equipment equipped with a device for adjusting the detection means 2 Optical system 3. Detection means, detection unit, optical system 4 Positioning device 5 Additional Measurement Systems 6 Detection unit for the rear side of the substrate holder, additional detection means 7 Positioning device for additional measuring systems 8 Frames, Tables 9 Substrate holder, first substrate holder (to be aligned) 10. Device for moving substrate holder to be aligned 11 Second board holder 12 Second moving device 13. Substrate transformation device 14,14',14'',14'''' Adjustment marking field, Alignment marking field 15,15' Adjustment mark, adjustment marking, reference marking 16,16' Layer of Adjustment Marking Field 17,17',17'' Spacing between vertically aligned adjustment marks 18,18',18'' Coordinate marking field plane 19 Focal area of ​​the detection means, focal area of ​​the optical system 20 Substrate holder surface 21,21' ridges, pins, protrusions 22 Angle, wedge error 23 1st position 24 2nd (adjustment) position 25 Optical axis

Claims

1. A device for adjusting detection means (3, 6), comprising: i) a substrate holder (9) for accommodating a substrate; ii) at least one alignment marking field (14, 14', 14'', 14''') with an alignment mark (15, 15') arranged in a fixed position with respect to the substrate holder (9); iii) said detection means (3,6) for detecting said alignment marks (15,15'); In an apparatus having at least 4. The apparatus according to claim 3, wherein the detection means (3, 6) are adjustable relative to the substrate holder (9) based on the adjustment marks (15, 15') arranged above and below the adjustment marking fields (14, 14', 14'', 14''').

2. 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 in a second plane (18, 18', 18''), the first plane (18, 18', 18'') and the second plane (18, 18', 18'') being arranged parallel to one another, and the first plane (18, 18', 18'') and the second plane (18, 18', 18'') having a distance (17, 17', 17'') from one another.

3. 3. Apparatus according to claim 1 or 2, wherein the detection means (3, 6) is adjustable by a relative movement between the detection means (3, 6) and the substrate holder (9).

4. 4. The device according to claim 1, wherein the detection means (3, 6) is adjustable by changing the focus of the detection means (3, 6).

5. 5. The apparatus according to claim 1, wherein the alignment marks (15, 15') of the first plane (18, 18', 18'') and the alignment marks (15, 15') of the second plane (18, 18', 18'') are aligned one above the other.

6. 6. The device according to claim 1, wherein the alignment marks (15, 15') of the first plane (18, 18', 18'') and the alignment marks (15, 15') of the second plane (18, 18', 18'') are regularly offset above and below each other.

7. 7. The device according to claim 1, wherein the alignment marks (15, 15') of the first plane (18, 18', 18'') and the alignment marks (15, 15') of the second plane (18, 18', 18'') are arranged in different layers (16, 16') offset from one another in a stepped manner.

8. 8. The device according to claim 1, wherein the alignment marks (15, 15') each additionally have an information content which is separate and detectable by the detection means (3, 6).

9. 9. Apparatus according to claim 1, characterized in that the detection means (3, 6) are optical detection means, in particular optical systems with a determinable central optical axis.

10. 10. The apparatus according to claim 1, wherein the substrate holder (9) has regularly arranged raised portions (21, 21') on the substrate holder surface (20) for providing a substrate receiving surface, and a plurality of alignment marking fields (14, 14', 14'', 14''') each having an alignment mark (15, 15') are regularly offset from one another and arranged between the raised portions (21, 21').

11. The apparatus according to any one of the preceding claims, wherein one of the two planes of at least one of the adjustment marking fields (14, 14', 14'', 14''') is mounted on the substrate holder surface (20).

12. 12. The apparatus according to claim 1, wherein at least one of the adjustment marking fields (14, 14', 14'', 14''') is completely embedded in the substrate holder (9), and the substrate holder (9) is at least partially arranged below the substrate holder surface (20).

13. Apparatus according to any one of the preceding claims, wherein the detection means (3, 6) are operable to read out alignment markings of the substrate.

14. 1. A method for adjusting a detection means, comprising the steps of: i) providing a substrate holder (9) having an alignment marking field (14, 14', 14'', 14''') with an alignment mark (15, 15'), the alignment marking field (14, 14', 14'', 14'', arranged in a fixed position relative to the substrate holder (9); ii) adjusting said detection means (3, 6) relative to said substrate holder (9); 20. The method of claim 19, further comprising:

13. A method according to claim 12, further comprising adjusting said detection means (3, 6) on the basis of said adjustment marks (15, 15') of said adjustment marking fields (14, 14', 14'', 14''') arranged one above the other.

15. The adjustment of the detection means in step ii) comprises the following steps having the following order: a) detecting a first alignment mark in a first plane (18, 18', 18'') of said alignment marking field (14, 14', 14'', 14'''); b) detecting a second alignment mark in a second plane (18, 18', 18'') of said alignment marking field (14, 14', 14'', 14'''); c) determining a wedge error between said detection means (3, 6) and said substrate holder (9); d) compensating for the wedge error determined in step c); having 15. The method of claim 14, wherein the first plane (18, 18', 18'') and the second plane (18, 18', 18'') are arranged parallel to each other, and the first plane (18, 18', 18'') and the second plane (18, 18', 18'') have a distance (17, 17', 17'') from each other.

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