Apparatus and method for adjusting detection means

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

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

[0003] The bonding of aligned semiconductor substrates is referred to as bonding. In this case, in order to avoid bonding errors and keep the scrap rate low, it is required to align multiple substrates or one substrate as accurately as possible. Furthermore, for many applications, the highest possible accuracy is required. For this purpose, the alignment marks on the substrate or the substrate holder are measured relative to each other. In this case, optical detection means in particular are used to detect the alignment markings and align the substrate.

[0004] For example, during bonding, the substrates to be bonded are aligned with each other and connected to each other in subsequent process steps. In this case, particularly accurate alignment of the substrates with each other is always necessary. In the following text, bonding is preferably fusion bonding. The alignment process of providing alignment markings on the surfaces of the substrates to be bonded is referred to as face-to-face alignment. During alignment, the alignment error also increases due to the relatively large movement distance.

[0005] Another problem with conventional technology is that the increasingly stringent alignment accuracy requirements can no longer be achieved by simple means. Methods that measure the substrate relative to a reference point and then align it without visual inspection, for example, after bringing it close to a contact point, cannot meet the new alignment accuracy requirements.

[0006] For example, U.S. Patent No. 6,214,692 is based on the comparison of two images of alignment markings and positional correction. The locations of the alignment markings on two face-to-face substrates are detected individually using a camera system. Based on the calculated relative locations and relative positions of the alignment markings, the positioning table (substrate holder and step) is driven and controlled to correct any incorrect positions.

[0007] Another publication, U.S. Patent No. 10692747, is based on the comparison and positioning correction of a total of three images of flat alignment markings. The locations of the alignment markings on two face-to-face substrates are detected individually using a camera system. A third detection unit detects the third alignment marking, which creates a correlation between the substrate alignment marks and the back surface of the substrate holder or the substrate, thereby enabling more accurate alignment of the two substrates.

[0008] In this respect, visual control in face-to-face alignment of two substrates is either impossible or only possible if at least one of the substrates is at least partially transparent. Therefore, precise surface alignment during face-to-face alignment is laborious and only possible to a limited extent.

[0009] A particular disadvantage is that the optical detection means for individual alignment markings are positioned inaccurately relative to the substrate holder, and consequently, relative to the substrate that will later be placed in the substrate holder. Due to the inaccurate positioning of the detection means, detecting individual alignment markings generally requires readjustment and focusing movements in the lateral plane of the substrate holder. By specifically controlling and moving the detection means, the spatial location of the detection means, especially optical detection means, such as a measuring microscope, often becomes so inaccurate that accurate measurement and, consequently, sufficiently accurate alignment of the substrate stack become impossible.

[0010] In particular, the readjustment movement of the optical system for detecting alignment marks is performed not only with the necessary movement but also with parasitic movements superimposed on it, and these parasitic movements cause deviations from the ideal movement of each optical system. Consequently, during movement, the central axis of the detection means may become tilted, and this tilt also negatively affects the alignment accuracy.

[0011] Therefore, an object of the present invention is to present an improved apparatus and method for adjusting a detection means that at least partially, and especially completely, eliminates the drawbacks of the prior art. An object of the present invention is to present an improved apparatus and method for adjusting a detection means. An object of the present invention is to present an apparatus and method for adjusting a detection means that takes into account the relative inclination with respect to the substrate holder and is easy to implement. Another object of the present invention is to present a method and apparatus for improving substrate alignment that, in particular, reliably, accurately and easily identifies, compensates for, i.e., adjusts for wedge errors between the substrate holder and the detection means.

[0012] This problem is solved by the features of multiple parallel independent claims. Advantageous variations of the present invention are presented in the dependent claims. Within the framework of the present invention are all combinations of at least two features shown in the specification, claims, and / or drawings. Within the range of values ​​presented, values ​​within the enumerated boundaries should also be considered disclosed as boundary values ​​and may be claimed in any combination.

[0013] Therefore, the present invention is an apparatus for adjusting a detection means, and the apparatus is at least, i) A substrate holder for housing the substrate, ii) At least one adjustment marking field with adjustment marks, which is positioned in a fixed position relative to the substrate holder, iii) In an apparatus having detection means for detecting adjustment marks, The detection means is characterized by being adjustable relative to the substrate holder based on adjustment marks on adjustment marking fields arranged vertically.

[0014] The present invention further relates to a method for adjusting a detection means, the method comprising at least the following steps, namely, i) A step of preparing a substrate holder which is positioned in a fixed position relative to the substrate holder and has an adjustment marking field with adjustment marks, ii) A method comprising the step of adjusting a detection means relative to a substrate holder, characterized in that the detection means is adjusted based on adjustment marks of adjustment marking fields arranged above and below.

[0015] In other words, the detection means is advantageously aligned based on two adjustment markings on an adjustment marking field, which are positioned vertically at different heights. In this case, wedge error (angle error) between the detection means and the substrate holder is particularly preferably compensated for. Thus, the tilt position of the detection means can be adjusted and calibrated based on a single adjustment marking field with adjustment marks positioned vertically. In this publication, the terms wedge error and angle error are used synonymously.

[0016] The detection means is preferably also configured to read alignment marks (on the substrate or in the substrate holder) during bonding, thereby improving alignment accuracy through prior adjustment. In particular, the substrate holder is further configured to accommodate and prepare the substrate as flat as possible. The adjustment marking field is positioned in a fixed position relative to the substrate holder, so that each adjustment mark also has a specific or known position with respect to the substrate holder. Preferably, the location of each individual adjustment mark in the adjustment marking field is known, so that after detecting two adjustment marks positioned vertically, alignment can be performed based on the detected adjustment markings with known locations. For this reason, the detection means or parallel axis errors can be compensated based on the vertically positioned adjustment marks without moving relative to the substrate holder (x and y axes) parallel to the substrate holder. After such adjustment, in particular, the detection axis of the detection means is aligned perpendicular to the substrate holder, so that tilt positions no longer occur, or the angular error of the detection means can be eliminated by the device. Any unknown angular error in the detection means can also cause alignment errors, thus reducing the scrap rate during substrate processing.

[0017] For this purpose, the detection means is movable, particularly by a moving device, especially along the focal axis (in the z-direction perpendicular to the substrate holder). Preferably, the tilt position or inclination position of the detection unit can be compensated for by a particularly sensitive actuator. Furthermore, the wedge error obtained between the detection unit and the substrate holder or the substrate housing surface of the substrate holder may also be caused by the compensatory movement of the substrate holder.

[0018] Adjustment marks are markings attached to and / or within the substrate holder, and these markings allow for adjustment of at least one of the detection means relative to the substrate holder. Preferably, a plurality of adjustment marking fields, each having its own adjustment mark, are distributed on the substrate holder in specific areas that are preferably aligned to the positions of later alignment marks.

[0019] This allows the detection unit to advantageously detect the adjustment marks in the adjustment marking field regardless of the x and y positions. In this case, further movement is possible to read the alignment marks without having to move the detection means in the x and y directions.

[0020] A special advantage of this apparatus and method for calibration is that a reference wafer or another additional measurement system is not required to align the detection means and the substrate holder relative to each other. This allows this form of calibration to be performed easily and frequently between individual processing steps. Another particularly special advantage of this apparatus and method for calibration is that the detection means is specially adjusted at the location where the measurement is also performed by multiple adjustment marking fields at different positions. This takes into account external influences, such as table deflection due to the weight of the optical system, and prevents the detection unit from becoming tilted later.

[0021] A substrate holder having at least one adjustment marking field may be composed of a plurality of separate components. The substrate housing surface is preferably a repeatable, at least slightly deformable plate, which is held in the substrate holder without restraint. The adjustment marking field consists of at least one adjustment mark and another adjustment mark.

[0022] This adjustment marking field is positioned in a fixed location relative to the substrate holder or the surface of the substrate holder. In particular, the exact location of the adjustment marking field and the location of each adjustment mark are known, relative to or on the substrate holder. Here, the adjustment marks or at least two adjustment marks of the adjustment marking field are positioned vertically.

[0023] In one preferred embodiment of the apparatus, the alignment marks of the adjustment marking field are arranged on a first plane and a second plane, the first and second planes being parallel to each other and spaced apart from each other. In other words, the adjustment marks on different planes are spaced apart by a known constant interval. This allows for advantageously accurate adjustment. Preferably, all planes of the adjustment marking field are identically positioned with respect to the substrate holder. This allows for advantageously accurate identification and, in particular, calculation of the wedge error between the detection means and the substrate holder based on the known interval.

[0024] In another preferred embodiment of the apparatus, the detection means is specified to be adjustable by relative movement between the detection means and the substrate holder. In other words, after detecting a first adjustment mark on a first plane, a second adjustment mark on a second plane of the adjustment marking field is detected by moving the substrate holder or the detection means in the z direction. The length of the movement path can be compared with the spacing between the planes of the adjustment marking field, thereby allowing for the identification of the tilt position or wedge error.

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

[0026] In one preferred embodiment of the device, the adjustment mark on the first plane and the adjustment mark on the second plane are specified to be arranged vertically one above the other. In this case, the adjustment marking field and the detection means are configured to enable detection of different aligned adjustment marks.

[0027] For example, the adjustment marking field is transmissive for a predetermined wavelength.

[0028] In another preferred embodiment of the device, the adjustment mark on the first plane and the adjustment mark on the second plane are specified to be arranged vertically and regularly shifted relative to each other. In this way, the detection unit can advantageously and easily detect the adjustment marks.

[0029] In another preferred embodiment of the device, the adjustment mark on the first plane and the adjustment mark on the second plane are specified to be arranged in different layers with a stepped shift relative to each other. In this way, advantageously, due to the material of the adjustment marking field, the adjustment marks on different planes are not covered. Furthermore, it is selectable from a plurality of detection means.

[0030] In another preferred embodiment of the device, the alignment marks are additionally each specified to be detectable by the detection means and to contain individual information content. In this way, the location of the alignment marks detected in the alignment marking field and / or with respect to the substrate holder can be known. At this time, the known x-y positions of the alignment marks and their individual pattern (e.g., pixel) positions are preferably known. Thereby, advantageously, when identifying the wedge error, the information content (prepared as a barcode, for example) can be captured. Thereby, the wedge error can be determined more accurately and with high reliability. Furthermore, based on the alignment marks, the location of the substrate can be subsequently identified relatively.

[0031] In another preferred embodiment of the device, the detection means is specified to be an optical detection means, particularly an optical system having a determinable optical central axis. This central axis is exactly perpendicular to the substrate holder or the surface of the substrate holder when the alignment is optimal, and thus also perpendicular to the alignment marks. Thereby, based on refocusing or changing the focus, the movement of the focal region along the optical central axis can be particularly accurately identified.

[0032] In another preferred embodiment of the apparatus, to prepare the substrate housing surface, the substrate holder is specified to have regularly spaced ridges on the substrate holder surface, and a plurality of adjustment marking fields, each having an adjustment mark, are arranged regularly offset from one another between the ridges. The ridges are preferably projections or pins. In this way, the contact area between the substrate and the substrate holder or substrate housing surface is advantageously small, thereby minimizing or preventing contamination of the substrate surface. The plurality of adjustment marking fields arranged between the ridges advantageously allow the identification of wedge errors at multiple positions. This eliminates the need for relative movement of the detection means in the xy direction, i.e., along the substrate holder surface. Rather, this is advantageous in that the detection means can identify wedge errors accurately and independently of position, and the detection means can be precisely aligned or adjusted.

[0033] In another preferred embodiment of the apparatus, at least one adjustment marking field is specified to have a height lower than the raised portion relative to the substrate holder surface. Thus, the raised portion protrudes relative to the adjustment marking field with respect to the substrate holder surface. 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 this apparatus, at least one of the two planes of an adjustment marking field is specified to be located on the substrate holder surface. In other words, the plane of the adjustment marking field is formed by the substrate holder surface. The adjustment mark may be partially embedded in the substrate holder or positioned below the substrate holder surface. In this way, the adjustment marking field can be constructed particularly easily and with little error. Furthermore, the adjustment marking field can be directly incorporated into the substrate holder.

[0035] In another preferred embodiment of the apparatus, at least one adjustment marking field is specified to be fully embedded in the substrate holder and positioned at least partially below the substrate holder surface. In other words, the plane is engraved into the substrate holder and has a negative height profile relative to the substrate holder surface. In this way, the adjustment marking field can be advantageously embedded in the substrate holder and formed directly during manufacturing. Furthermore, the adjustment marking field is advantageously protected.

[0036] In another preferred embodiment of the apparatus, the detection means is specified to be usable for reading alignment markings on a substrate. In this case, the alignment marking field is particularly preferably located in a region of the substrate holder surface that aligns with the position of the alignment marking field on the substrate or substrate holder. Advantageously, the detection means can also align the alignment markings without the need for relative movement in the x and y directions. Rather, the detection means can remain stationary, and the reading can be performed by focusing or moving the focal region.

[0037] In one embodiment of the apparatus, the apparatus is configured to be sealed, so that at least the substrate holder and detection means are incorporated into an equipment chamber that can be sealed airtight and / or vacuum-sealed from the atmosphere. Corresponding auxiliary units include, for example, an inlet, gate, pump, sensor, viewing window, gas supply unit, and temperature control device. In this embodiment, the equipment chamber can be filled with a special atmosphere, preferably free of water or water vapor. Furthermore, this special atmosphere may not contain oxygen. In another embodiment, a vacuum, preferably a high vacuum, and particularly preferably an ultra-high vacuum can be applied to the equipment chamber. The vacuum in the equipment chamber of this embodiment is less than 1 × 10⁻³ mbar, preferably less than 1 × 10⁻⁵ mbar, particularly preferably less than 1 × 10⁻⁸ mbar, particularly very preferably less than 5 × 10⁻⁹ mbar, most preferably less than 1 × 10⁻¹⁰ mbar, and in the ideal case less than 1 × 10⁻¹² mbar.

[0038] In one preferred embodiment of this method, the adjustment of the detection means is performed in step ii) in the following order, namely, a) A step of detecting a first adjustment mark on the first plane of the adjustment marking field, b) A step of detecting a second adjustment mark on the second plane of the adjustment marking field, c) A step of determining the wedge error between the detection means and the substrate holder, d) A step of compensating for the wedge error determined in step c), The first plane and the second plane are arranged parallel to each other, and are specified to have a gap between them.

[0039] Advantageously, this method allows for calibration of the detection means or compensation of wedge errors without the need for a reference wafer or another additional measurement system. This form of calibration can be repeated multiple times between wafer bonding processes without the need to move the detection means. Furthermore, the detection means can remain stationary and only require focus changes or focus area shifts to detect calibration marks on different planes of the calibration marking field.

[0040] In one preferred embodiment of the apparatus, the adjustment marking field has another adjustment mark on a third plane, which is preferably also arranged parallel to another plane at predetermined intervals. Particularly preferred here are the different adjustment marks on different planes, offset in the z-plane, which are transparent to different wavelengths, so that any other adjustment mark on any plane of the adjustment marking field can be detected by the detection means without obstruction.

[0041] This allows for the detection of adjustment marks, and subsequently, adjustment marks placed on these adjustment marks, by comparing the known locations or the spacing between the planes of the adjustment marks with the detected measurements. Since the properties, structure, and locations of the adjustment marking field are preferably known, this allows for the detection of known spacings between adjustment marks, which can be used to correct the optical detection means. Based on this known spacing, for example, by moving the optical detection means relative to the adjustment marking field of a fixed substrate holder, the detection means can be adjusted and / or corrected based on vertically positioned adjustment marks without requiring movement of the substrate holder. In this way, the optical detection means can be precisely aligned in at least one direction, because the known spacing and spatial position between vertically positioned adjustment marks can be detected, and consequently, the actual position and angular position of each optical detection means can be calculated.

[0042] The relative locations of different adjustment marking fields are preferably similarly known, thereby the locations of all adjustment marks on the substrate holder are known. Here, the adjustment marking fields are positioned on the substrate holder, preferably in the edge region of the circular substrate holder surface in particular. In other words, the alignment marking fields are clustered in specific regions, particularly in areas where the alignment markings are aligned during substrate processing. That is, the adjustment marking fields are preferably provided at spatially dispersed locations on the substrate holder, where the substrate to be aligned and bonded includes the alignment marks. This makes the position and spatial alignment location of each optical detection means calculable relative to the substrate holder, and the deviation from the ideal position can be used as a correction value for bonding the upper substrate to the lower substrate.

[0043] The substrate holder preferably has a flat substrate mounting surface. Here, this substrate mounting surface of the substrate holder is particularly composed of a plurality of uniformly distributed mounting points and / or protrusions.

[0044] In another embodiment of the substrate holder, the substrate mounting surface has a configurable shape, which can be set depending on the substrate to be mounted. In this case, the locations of the adjustment marks remain known.

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

[0046] In one particularly advantageous embodiment of the substrate holder, adjustment markings and at least one additional adjustment marking are provided in the moving regions of the optical detection means and the additional optical detection means. This allows for even more precise adjustment of the detection means.

[0047] Adjusting the detection means relative to the substrate holder is used to eliminate or at least reduce error components that degrade the quality of substrate alignment results due to positional and / or angular errors of the detection means, particularly during fusion bonding. By specifying the alignment of the detection means relative to the substrate holder and the corresponding adjustment, 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 between the substrates.

[0048] Therefore, the adjustment marks positioned vertically and the additional height information they provide allow the detection means to be adjusted without additional movement of the substrate holder, because each movement is superimposed with parasitic movements that can ultimately increase the alignment error. Here, the measured positions of the adjustment marks and other adjustment marks (on different planes) are compared with the stored actual values. From the height difference and the same height deviation, correctable positioning errors can be identified.

[0049] Preferably, the adjustment marking field has multiple adjustment marks arranged side by side on each plane. This allows for the detection of at least one first adjustment mark or at least one second adjustment mark on the corresponding plane. Furthermore, the adjustment marking field between planes is preferably configured to be transparent to the detection means, thereby allowing for the detection of adjustment marks arranged vertically. It is also conceivable that the adjustment marks on the first plane are offset from the adjustment marks on the second plane, and that this adjustment marking field has different levels of elevation.

[0050] The detection means can further detect not only the adjustment marks on a particular plane, but also other adjustment marks on that plane if they are located in the focal area. The same applies to other planes. Preferably, the detection means is configured to be able to detect multiple adjustment marks on each plane, especially adjacent adjustment marks. This further improves the accuracy of determining the wedge error and allows for more effective adjustment of the detection means.

[0051] In another embodiment of the adjustment marking field, individual adjustment marks can be implemented as 3D structures with predetermined corners and / or edges, and each positional feature is assigned a unique coding (information content), which enables a unique mapping of corners and / or edges and / or steps to 3D positional information, and enables a complete spatial mapping between the substrate holder and the adjustment marking field.

[0052] Preferably, the alignment marks in the alignment marking field are detected at the position where the substrate alignment markings will be positioned in a subsequent step. Neither the substrate holder nor at least one detection means needs to be moved or repositioned as a result of positional movement, adjustment, and / or correction. The fixed position increases the accuracy of substrate alignment and, further, the accuracy of bonding.

[0053] The detection unit preferably has focusing means for focusing on or setting the focus on a first adjustment mark during detection, and preferably an objective lens. In this case, the detection unit or objective lens takes a focal position that allows the detection unit to detect a specific focal region. As a result, the detection unit or objective lens is focused on the focal region of the specific focal position, and adjustment marks located within this focal region are detectable. Preferably, during detection, only the adjustment marks on each plane are detectable or identifiable, because the detection unit contains exactly one plane in each focal region. Thus, the distance between the first plane and the second plane is preferably greater than the depth of the focal region, more preferably at least twice or greater.

[0054] For focusing, liquid lenses with variable curvature and / or rapidly switching, resonantly operating liquid lenses can also be used to simultaneously image multiple focal planes. Similarly, changing the refractive index of the lens can be considered for focusing and / or refocusing. The listed methods 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 on the first plane, the position of the detection means is fixed. This determines the focal region, so that the detection unit can then preferably detect only the adjustment marks within the determined focal region. Subsequently, the second plane is detected by refocusing perpendicular 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 on the second plane of the adjustment marking field. In this regard, the focusing movement of the detection unit is advantageous, as the detection unit is moved by the distance necessary for focusing.

[0056] This advantageously prevents alignment errors caused by the global repositioning of the detection unit and / or the fixed substrate holder. The known topography of individual adjustment marks in the adjustment marking field on the substrate holder, as well as their uniquely and a priori known xyz positions, allows for the calculation of the detection unit's angular error at the measured adjustment marks, particularly through actual focus shifts and measurements.

[0057] For this purpose, the measured values, particularly the measured intervals between different planes of the adjustment marks, the lateral displacement and / or torsion, are compared with stored ideal values ​​that are approximations of their true values, and the difference is used as a correction value for the other measurement.

[0058] If another adjustment mark is located on a different plane between the first and second planes, these adjustment marks can be measured by the detection unit during its focusing movement, thereby allowing for particularly precise and controlled movement of the detection unit. Furthermore, the detection of multiple adjustment marks whose locations are known within the adjustment marking field allows for even more accurate relative alignment and identification of correction values.

[0059] The adjustment marks preferably contain information about each location within the adjustment marking field. Here, in addition to the locations (x and y points) along the adjustment marking field, the height or spacing of each plane is also known. This allows, advantageously, when a first adjustment mark is detected, to determine which plane it is located on. In particular, if the adjustment marking field has three or more planes at different intervals from each other, this allows for easier open-loop or closed-loop control of alignment and focusing, because the height information for each adjustment mark is detected. For example, during continuous detection during movement or when detecting the first adjustment mark, it is advantageous to determine which plane or step and which position in the focal region is detected. Furthermore, if a position is detected between two planes or steps, it is advantageous to approach the plane or step located above or below it. Advantageously, it is also possible to detect and control the location at the x and y positions.

[0060] Preferably, the apparatus is configured such that the focal position of the detection unit can be fixed immediately after detecting the first adjustment mark on the first plane of the adjustment marking field. In this case, the fixed focal position of the detection unit determines the clearly imaged focal region. In this way, the moving device can be advantageously brought closer to the distance between the first plane and the second plane, and thus it can be brought into focus. The detection unit is further held in a fixed position, particularly in the lateral direction, so that it can be brought closer to the distance between the planes only by detecting the adjustment mark and moving the detection means in the z direction. This is advantageously brought into account by direct visual control by a single detection unit, and thus the precise alignment of the detection means with respect to the substrate holder can be verified.

[0061] In one possible embodiment of the apparatus for adjusting the detection means, at least one adjustment marking field is specified to be located on the back surface of the substrate holder, facing away from the substrate holder surface. The adjustment marking field may, for example, be mounted on the back surface or fitted into the substrate holder. Furthermore, the adjustment marking field may be formed by the substrate holder itself. The detection unit can advantageously be located on the back surface facing away from the substrate holder surface.

[0062] In one preferred embodiment of the apparatus for adjusting the detection means, the center point of the adjustment marking field is specified to be aligned at least partially with the center point of the substrate holder surface. By centralizing the adjustment marking field, the adjustment of the detection means relative to the substrate holder can be performed advantageously and accurately. This embodiment also advantageously allows for the sensing of linear error components or rotation of the detection unit relative to the substrate holder.

[0063] Preferably, the adjustment marking field has at least three planes having adjustment marks, where the adjustment marks are provided with information on which plane they are located on. In this way, the device can be approached to a plurality of specific intervals, thereby allowing multiple focal positions, and consequently predetermined intervals between the detection means and the substrate holder, to be set during adjustment. The intervals between these planes may be the same size. However, preferably, these planes are arranged at different intervals from one another. In this way, multiple intervals can be flexibly approached. Setting different focal planes, and therefore different specific relative intervals between the detection means and the substrate holder, may be advantageous when the thickness of the substrates is different.

[0064] In one preferred embodiment of the apparatus for adjusting the detection means, the apparatus has at least one additional adjustment marking field and at least one additional detection unit for detecting the at least one additional adjustment marking field, wherein the at least one additional adjustment marking field is specified to be fixedly positioned relative to the substrate holder. A combination of multiple measurements for the additional adjustment marking field allows for detection at multiple points, thus enabling more accurate alignment. For example, in this way, displacement and / or rotational errors can be identified. Here, the adjustment marking field and at least one adjustment marking field are preferably offset along the substrate holder. Particularly preferably, the apparatus has a total of three adjustment marking fields and three detection units, which are each distributed around the center point of the substrate holder surface and offset from each other, particularly radially.

[0065] The alignment markings may be any objects that can be aligned with one another, such as cross-shaped, circular, square, or propeller-shaped formations or grid structures, particularly phase grids in the spatial frequency domain. Furthermore, 3D objects such as pyramids, cones, and steps can be used as alignment markings.

[0066] In one particularly advantageous embodiment of the apparatus, the adjustment markings may include, at least partially, a QR code, which in particular represents the absolute machine-readable positional coating (x,y,z position) of each adjustment mark, thereby enabling a complete mapping between the substrate holder and / or the substrate holder surface and the adjustment marking field before using the substrate holder, for use as a reference value for all adjustment processes.

[0067] In one particularly advantageous embodiment, the adjustment markings may include at least partially alphanumeric symbols, in particular, representing the absolute, machine-readable positional coding (x, y, z position) of each adjustment mark. The alphanumeric symbols are preferably also readable by the operator.

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

[0069] Therefore, this adjustment marking field 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 x and y directions are particularly adapted to the focal area of ​​the optical detection means, thereby allowing observation of at least two steps or alignment mark planes, respectively.

[0071] Here, the number of steps and the total height of the adjustment marking field are preferably matched to the interval to be adjusted. For example, if the goal is to set a focusing interval of at least 500 micrometers, preferably 550 micrometers of height-coded positional information is mapped in the adjustment marking field, thereby uniquely approaching this interval.

[0072] Detection is preferably performed by a corresponding imaging optical system, thereby allowing the depth of field to be selected such that it is smaller than the step height or layer thickness of the adjustment marking field. Depth of field (DOF) is the region in the image space of the imaging optical system in which a sufficiently sharp image of the object being focused on, particularly the alignment marking or adjustment marking, is produced. 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 the detection of the adjustment mark on the adjustment marking field is performed at a small depth of field, which is smaller than the step height, preferably smaller than half of this step height, and particularly preferably smaller than 0.1 × step height, the position of the adjustment marking field can be uniquely determined, especially 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, most preferably less than 5 micrometers, and in the optimal case less than 4 micrometers.

[0075] In contrast, when the depth of field is large and at least two step heights are clearly imaged, the positioning uncertainty of this device increases. This is because it becomes impossible to uniquely associate the z height with a single step.

[0076] In one preferred embodiment of the device, the image detection means or 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 both steps appear equally clear. The determination of which adjustment mark to use can be made (also as a computer-implemented independent method) by the slight displacement of the image detection means.

[0077] When detecting adjustment markings, the detection is physically limited, and in particular, only one plane or step is clearly imaged. Preferably, in this regard, only one step or plane is located in the focal region of the detection unit. Since the adjustment markings in the adjustment marking field are position-coded and spatial-coded, the positional information of the substrate holder and / or detection means in the spatial coordinate system can be determined from the clearly detected adjustment marks on the plane. By refocusing the detection means on another adjustment marking, the angular error of the detection means can be determined in particular from the magnitude of the known step height and from the measured same height deviation of the adjustment mark, and this angular error can be used as a correction value for the alignment of the substrate stack.

[0078] This adjustment method enhances alignment accuracy, particularly by supplying correction values ​​for local angular errors in the detection unit. These correction values ​​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 adjusting, aligning, and bonding the substrate preferably includes a software-assisted control unit, which performs the steps described herein and controls the components. Here, closed-loop and closed-loop control should be understood to be included in the control unit.

[0080] The X-direction and Y-direction, or X-position and Y-position, are understood to be directions or positions that extend or are positioned on the XY coordinate system, or on any Z-plane of the XY coordinate system. The Z-direction is positioned orthogonal to the XY direction. The X-direction and Y-direction preferably correspond to lateral directions along the plane of the adjustment marking field or along the surface of the substrate holder. The Z-direction preferably is the direction in which the detection means moves when the focal position of the detection unit is fixed on the XY plane.

[0081] Positional features are calculated or detected from the positional and / or locational values ​​of positional markings on the substrate holder, in particular by detecting and evaluating this adjustment marking field.

[0082] The alignment marking field is preferably located near the alignment marking on the substrate. Particularly preferably, at least one alignment marking and adjustment marking field on the substrate are detectably positioned in the substrate holder without requiring lateral repositioning of the detection means. An additional alignment marking field may also be located on the back surface of the substrate holder, which can be used for adjusting the additional detection means and for aligning the substrate stack using correlated positions.

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

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

[0085] In another preferred embodiment of the apparatus, the two adjustment marking fields are preferably aligned in the z-direction with respect to the adjustment markings of the substrate holder, and are particularly located on the back surface of the substrate holder.

[0086] In another preferred embodiment of the apparatus, at least one adjustment marking field is provided near the substrate on the substrate side of the substrate holder or on the surface side of the substrate holder to optically detect an accessible position. These additional detection means can be aligned with the substrate holder in the first method and can be used as additional detection means to align the substrate in the second method.

[0087] In one further embodiment of the apparatus, at least two adjustment marking fields are included near the substrate edge on the substrate side of the substrate holder to optically detect an accessible position. This advantageously allows the substrate holder to be positioned horizontally.

[0088] The present method and apparatus for alignment particularly include at least one additional detection unit with a corresponding measuring system and / or closed-loop control system, and at least one additional adjustment marking field and / or alignment marking field, wherein the alignment accuracy is further enhanced by correlating the additional measurement with at least one of the measurements of the additional detection unit. For this purpose, correction values ​​from multiple measurements are used.

[0089] In subsequent steps after adjusting the detection means using the correction, at least one of the measured additional alignment markings is correlated with at least one alignment mark in the alignment marking field, which is freely accessible and visible even when the substrates are aligned. This allows for direct observation of the alignment marks, and consequently, real-time measurement and closed-loop control during alignment. This further enhances the alignment accuracy of the substrates.

[0090] In another embodiment of the apparatus, at least one additional adjustment marking field is positioned on the substrate side of the substrate holder, near the periphery of the substrate, in a location that is continuously accessible to another detection unit. Particularly preferably, the surface of the adjustment marking field is in the same plane as the surface of the substrate to be bonded, which is fixed to the substrate holder.

[0091] By adding 3D positional features to the substrate holder that can be uniquely correlated with the positional features on the substrate, direct observation of the alignment markings on the substrate holder can replace direct observation of the alignment markings on the substrate. This has the advantage that the observable portion of the substrate holder can be positioned substantially always within the field of view or detection area of ​​the detection unit. Correction of the 3D positional information and angular position of the detection means enables higher precision in the alignment of substrates.

[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, and particularly preferably less than 1 mm × 1 mm.

[0093] By actively feeding back data for positioning and position correction, accuracy is improved compared to open-loop controlled positioning in conventional techniques. This is because, in a closed control loop, the actual state of position can be controlled.

[0094] A correlation is formed between the alignment marks of the first and / or second substrates on each contact surface of the substrate and at least one alignment mark in the alignment marking field. One alignment mark in the alignment marking field is particularly directly detectable by the detection unit during alignment.

[0095] The ability to directly detect or observe at least one additional adjustment mark on an additional adjustment marking field enables real-time measurement of the 3D position of the substrate holder or detection means. The same device can be used to reduce alignment errors during substrate alignment or substrate bonding, particularly fusion bonding. This improves alignment accuracy because detection of the alignment marking field, along with the supply of correction values ​​and calculated height information, eliminates positioning uncertainty, thereby reducing error propagation. This means that the number of required feed movements is reduced, and alignment accuracy is improved by closed-loop control of height adjustment during bonding.

[0096] A detection unit for detecting an alignment marking field is, in particular, part of an optical system for detecting an alignment marking field, and according to an advantageous embodiment, includes beamforming and / or deflection elements, particularly for Kohler illumination, e.g., mirrors, lenses, prisms, beam sources, etc., as well as image detection means, e.g., a camera (CMOS sensor or CCD, or surface detection means or row detection means or point detection means, e.g., a phototransistor, etc.), moving means for focusing, and evaluation means for closed-loop control of the optical system.

[0097] In another embodiment of this apparatus, the optical system can be used in combination with a rotation system for substrate positioning according to a turnover adjustment method (see Friedrich Hansen, Justierung, VEB Verlag Technik, 1964, Section 6.2.4, Umschlagmethode). Thus, during turnover adjustment, at least one measurement is taken at a predetermined position of each substrate holder, and at least one measurement is taken at the turned-over position, rotated 180 degrees and oriented in the opposite direction. The measurement results obtained in this way are particularly free from eccentricity errors. Preferably, the substrate holder can be rotated, while the detection means remains fixed in position except for focusing.

[0098] An advanced version of this device for adjustment can be used as a device for aligning circuit boards.

[0099] The apparatus may further include a system for fabricating prebonding. For this purpose, pressure pins and / or configurable nozzles can be used to initiate fusion bonding for joining the substrates. In particular, the configurable nozzles may be height-adjustable, thereby changing their relative position to the back surface of the substrate, and the nozzle volume flow rate can be changed under closed-loop control. These nozzles can be advantageously aligned based on adjustment markings located above and below.

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

[0101] These moving devices can generate individual movements as a result of individual movements, and thus the moving devices can preferably include a high-speed coarse positioning device that does not meet precision requirements and a fine positioning device that operates precisely.

[0102] A positioning device is understood to be a coarse positioning device if, with respect to the overall travel path or rotation range where one rotation in a rotatable rotary drive unit is 360 degrees, the approach accuracy and / or repeatability deviate from the target value by more than 0.1%, preferably more than 0.05%, and particularly preferably more than 0.01%.

[0103] Therefore, for example, in a coarse positioning device with a travel distance exceeding 600 mm (twice the substrate diameter), an approach accuracy of 600 mm × 0.01%, i.e., an approach accuracy exceeding 60 micrometers, is consequently obtained as residual uncertainty.

[0104] In another embodiment of coarse positioning, the residual uncertainty of approach accuracy or repeatability is less than 100 micrometers, preferably less than 50 micrometers, and particularly preferably less than 10 micrometers. Thermal disturbances should also be taken into consideration in this case.

[0105] The coarse positioning device performs its positioning role with sufficient accuracy only when there is a deviation in the range of motion of the corresponding fine positioning device between the actual position reached and the target value of that position.

[0106] A selective coarse positioning device performs its positioning role with sufficient accuracy only when there is a deviation of half the range of motion of the corresponding fine positioning device between the actual position reached and the target value of that position.

[0107] A positioning device is understood to be a fine positioning device if the residual uncertainty of the approach accuracy and / or repeatability with respect to the overall travel path or rotation range does not exceed 500 ppb, preferably 100 ppb, and more preferably 1 ppb from the target value.

[0108] Preferably, a precision positioning device can compensate for an absolute positioning error of less than 5 micrometers, preferably less than 1 micrometer.

[0109] The relative positioning of the substrates may be performed in all six degrees of freedom of motion, namely, three translational movements along the coordinate directions x, y, and z, and three rotational movements around the coordinate directions. In this case, the motion can be performed in any direction and orientation.

[0110] A robot for handling circuit boards is included in the mobile device. The holding unit may be incorporated into the mobile device as a component or functionally integrated.

[0111] Furthermore, the apparatus for adjusting the detection unit preferably includes a closed-loop control system and / or evaluation system, in particular a computer, to perform the steps described, especially the movement flow, to make corrections, to analyze and store the operating state of the apparatus.

[0112] The procedure is preferably created as a recipe and executed in a machine-readable format. A recipe is a set of optimal values ​​for functionally or process-technically relevant parameters. By utilizing a recipe, the reproducibility of the manufacturing flow can be ensured.

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

[0114] The alignment device may further include a frame, an exterior, and active or passive subsystems for suppressing, damping, or eliminating vibrations.

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

[0116] Both tactile and non-tactile measurement methods can be used. Measurement standards and units may exist as physical or material objects, particularly as scales, or they may be implicitly present in the measurement method, such as the wavelength of the beam used.

[0117] To achieve alignment accuracy, at least one of the following measurement systems can be selected and used. The measurement system performs the measurement procedure. In particular, • Induction methods, and / or • Capacity method, and / or • Resistive method, and / or • Comparison methods, especially optical image recognition methods, detection of position marks and / or QR codes, and / or • Incremental or absolute methods (especially by glass standards as scales, or by interferometers, especially laser interferometers, and by magnetic standards), and / or • Propagation time measurement (Doppler method, time of flight method) or other time detection method, and / or • Triangulation methods, especially laser triangulation, and / or • Autofocus system, and / or • Intensity measurement methods such as optical fiber distance meters can be used.

[0118] In particular, the measurement method described can be used in addition to the adjustment device to perform absolute position measurement in this apparatus, not only to detect and correct the local relative position and / or location of the detection means with respect to the substrate holder.

[0119] One particularly preferred embodiment of the alignment apparatus further includes 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 substrate holder relative to a given reference, in particular the frame. The measuring system includes at least one tuned detection unit.

[0120] Here, the 3D position of the substrate holder, preferably having a corrected angular position, is determined by the measurement system or the detection unit of the measurement system, thereby allowing for the determination of height information and inclination for position information at the same height from the measurement. For this purpose, at least one adjustment marking field consisting of steps and / or layers having unique position markings is detected.

[0121] The frame can be understood as a part composed of natural hard stone or mineral cast or spheroidal graphite cast or hydraulic concrete, which is formed in a vibration-damping and / or vibration-isolating manner and / or vibration-eliminating manner.

[0122] The idea can be similarly reversed by mounting the detection unit to the substrate holder and the adjustment marking field to, for example, the frame. In this case, the detection unit moves with the substrate holder, and the adjustment marking field is fixed to the frame.

[0123] To enable detection, evaluation, and open-loop control at any given time, particularly continuously, the adjustment marks of the adjustment marking field are distributed, according to an advantageous embodiment, to an area in each plane larger than the field of view of the image detection system of the detection unit, thereby supplying measurements particularly continuously to the open-loop control unit (and / or closed-loop control unit). However, here, for each position in the field of view of the image detection system, the adjustment marks of the adjustment marking field are designed so that height information can be detected from the adjustment marking field and / or from extended position information of the same height. In other words, at each lateral position of the substrate holder, the arrangement of the adjustment markings of the adjustment marking field allows for the detection of the spatial position of the detection means and the determination of angular position correction. In particular, since the relative position of the detection means exists as 3D position information, more accurate spatial alignment of the substrates fixed thereon can be performed.

[0124] For the determination of the XYZ position, the alignment apparatus may, in addition to at least one detection means, use at least one three-beam interferometer, particularly one with a monolithic reflector, configured accordingly to detect and / or pinpoint the XYZ position of the substrate holder. Structurally, the detection means and the interferometer are incorporated into an assembly so that they do not move independently of each other.

[0125] In one other advantageous embodiment of the apparatus, in addition to the apparatus for detecting the adjustment marks in the adjustment marking field, a measuring means, such as a prism-shaped monolithic reflector, may be additionally included, which is measured by a plurality of, in particular, three-beam interferometers. In this way, error propagation can be eliminated by averaging, difference formation and measurement sequence formation, and the alignment accuracy can be further improved. In other words, with sufficiently fast position measurement, a closed-loop control system can be used for the movement trajectory, thereby further reducing the position error of the substrate holder.

[0126] Devices for alignment and / or adjustment, particularly substrate holders formed from monolithic blocks, preferably have at least two of the following functions, namely: • Fixing the substrate by vacuum (vacuum track, connection part) and / or by electrostatic means. • Shape compensation for substrate deformation using mechanical and / or hydraulic and / or piezoelectric and / or pyroelectric and / or electrothermal operating elements. - Positioning and / or location (measurement standards, reflective surfaces and / or prisms, especially reflectors for interferometry, registration marks and / or registration mark fields, measurement standards for planarly formed planes, volumetric standards, especially steps, layer systems of known layer heights with adjustment markings divided into planes) with movement (guide tracks).

[0127] Movement devices not used for fine adjustment are preferably configured as robotic systems equipped with incremental displacement sensors. The precision of these movers for auxiliary movement is separate from the precision for alignment of the substrate stack, so that this auxiliary movement is performed with a low repeatability of less than 1 mm, preferably less than 500 micrometers, and particularly preferably less than 150 micrometers.

[0128] Open-loop and / or closed-loop control of the movement mechanism of the alignment device for (lateral) alignment (fine adjustment) is performed based on the detected XYZ position and / or alignment location. For this purpose, additional alignment marks on the substrate are correlated with adjustment marks on the adjustment marking field, which are uniquely associated with these marks in the field of view of the substrate holder surface. Height information and angular position, as well as their corrections, are calculated from the adjustment markings on the adjustment marking field. This provides the XYZ position and spatial orientation, which can be continuously observed, especially during the alignment feed motion and when setting the spacing for bonding, and can be used in real time, particularly for correcting errors in the feed motion.

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

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

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

[0132] In one particularly preferred embodiment of the substrate holder, the substrate holder may be composed of multiple components as a non-monolithic body. The substrate mounting surface includes at least one adjustment marking field with adjustment markings and, in particular, dispersed dot-like mounting areas for mounting the substrate. The substrate mounting surface forms part of an insert which is a reproducible elastically deformable body. The insert is particularly statically defined and housed in the substrate. The substrate mounting surface is fluidly connected, particularly to a vacuum, through correspondingly formed passages and nozzles and supply lines, and this negative pressure can also be replaced with positive pressure.

[0133] The insert is secured within the substrate. At least the back surface of the insert, facing away from the substrate holder surface, is hermetically isolated and housed within the substrate of the substrate holder, thereby allowing the insert to be reproducibly deformed by vacuum or positive pressure.

[0134] A closed-loop controlled positive or negative pressure can be independently supplied to the fluid connection between the substrate space of the substrate holder and the back surface of the insert, causing deformation of the insert.

[0135] One exemplary embodiment of a method for adjusting the detection means is carried out in particular in the following order, specifically in the following steps.

[0136] Step 1: Move at least one detection means to the expected position of the alignment markings on the substrate to be aligned. This positioning is subject to positioning uncertainty.

[0137] Step 2: Secure the circuit board holder so that it does not move.

[0138] Step 3: Focus the detection means on the adjustment marking in the adjustment marking field and detect the adjustment marking.

[0139] Step 4: Retrieve the stored location of the adjustment marking from the knowledge storage device and / or database and associate it with the measured value detected by the detection means. This stores the spatial location, in particular the absolute location, of the detected adjustment marking.

[0140] Step 5: Focus the detection means on another adjustment marking on the second plane of the adjustment marking. In this step, the device preferably performs only a focusing movement in the z direction.

[0141] Step 6: Detect another adjustment mark and calculate the location and position of the other adjustment mark.

[0142] Step 7: Calculate the relative and / or angular position of the detection means with respect to the local normal direction of the substrate holder, particularly from the known height and calculated focus height from the storage device, and particularly from the xy lateral displacement of another adjustment marking. This value can be used as a correction value for subsequent steps.

[0143] In one advantageous embodiment, the searched adjustment markings are detectable within a radius of less than 3 millimeters, preferably less than 2 millimeters, particularly preferably less than 1 millimeter, most preferably less than 500 micrometers, and even more preferably less than 250 micrometers, around the optical axis of each objective lens of the detection unit.

[0144] A measurement system, equipped with at least one detection unit (particularly a measuring microscope with an objective lens) for detecting the adjustment marks on the adjustment marking field, detects the first adjustment marks on the first plane, and consequently the XYZ position and / or alignment location of the substrate holder. The substrate holder is fixed in place, and the position of additional alignment markings on the substrate below is correlated to the detected position. An adjustment marking field, fixedly positioned relative to the substrate holder, is used to detect the position of the substrate holder.

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

[0146] At this focusing position, the focal position of the detection unit, and consequently the focal area (particularly of the objective lens), is fixed in order to detect the adjustment marking field. The detection unit is further fixed or held in a fixed position, particularly locally.

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

[0148] The position of the substrate holder is corrected using the measured positional and / or angular errors, at least in the lateral plane. In this process, the detection means is moved to focus on at least one corresponding second adjustment mark on the second plane, or so that it is located within the focal area of ​​the detection unit. In this way, visual control ensures that the distance between the first and second planes is approached sufficiently accurately.

[0149] This allows the use of correction values, eliminating the need to reposition the substrate holder and avoiding alignment errors. Height information is supplied via the adjustment marking field. When aligning substrates to each other, if the alignment error exceeds the determined boundary value, correction can be performed on the relative position of the substrates. This adjustment method supplies correction values ​​for such corrections.

[0150] The alignment errors to which correction can be applied are 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 to correction for torsion is less than 50 microradians, preferably less than 10 microradians, particularly preferably less than 5 microradians, most 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, this method measures different planes of the adjustment marking field according to a predetermined sequence of relative movement, thereby deriving the relative positions and / or alignment points of the two measured objects, and thereby forming correction values ​​that further improve 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, relative movement will result in displacement and / or angular errors (yaw errors and / or pitch errors and / or roll errors) in the xy plane, which are detectable and correspondingly correctable.

[0154] In particular, a substrate holder incorporating an adjustment marking field can be understood as an independent device. Preferably, the substrate holder includes at least one adjustment mark of the adjustment marking field and is positioned below the substrate mounting surface of the substrate holder so that no contact occurs between the substrate and the adjustment mark when the substrate holder is in use. In other words, the adjustment mark of the adjustment marking field and the substrate do not come into contact at any point when the substrate is placed on the surface of the substrate holder. Particularly advantageous is the use of a protruding sample holder incorporating an adjustment marking field.

[0155] In one advantageous embodiment of the substrate holder, individual adjustment marks of the adjustment marking field can be positioned on the substrate holder so that they are located on the substrate around the alignment marks. The purpose of this arrangement is to calibrate and / or adjust the device without a substrate using the detection means, in particular to measure the angular error of the individual detection means, so that the calibration values ​​of the device can be used during alignment. Preferably, after calibration, the detection means are locked and fixed in this position. This allows the adjustment marks on the substrate to be detected without readjusting the detection means when using the substrate holder to align the substrate. In other words, the z-axis of the alignment marks of the alignment marking field locally coincides with the z-axis of the alignment marks on the substrate in the field of view of the individual detection means. This allows the calibrated detection means and substrate holder to be used for substrate alignment without repositioning.

[0156] The concept of axis coincidence, or congruence, parallelism, or perpendicularity, is used in this disclosure as a concept of quantities with tolerances, thereby, unless otherwise expressly indicated, tolerances in accordance with ISO 2768 apply to non-permissible length or angle dimensions. [Brief explanation of the drawing]

[0157] Further advantages, features, and details of the present invention will become apparent from the following description of preferred embodiments and from the drawings. These drawings schematically illustrate: [Figure 1] This is a cross-sectional view of one embodiment of a device for adjusting a detection means. [Figure 2a] This is a plan view illustrating the arrangement of adjustment marks or adjustment marking fields between the raised portions of a substrate holder. [Figure 2b] This is a cross-sectional view of one embodiment of an adjustment marking field. [Figure 3] This is a plan view of one embodiment of an adjustment marking field with adjustment marks. [Figure 4] This is a cross-sectional view of one embodiment of an adjustment marking field equipped with a detection unit. [Figure 5a] This is a diagram showing the detection unit in the first position. [Figure 5b] This is a diagram showing the detection unit in the second position.

[0158] The drawings illustrate the advantages and features of the present invention. The illustrated embodiments are denoted by reference numerals. Individual components or features having the same or the same function are denoted by the same reference numerals.

[0159] Figure 1 shows a schematic functional diagram of a device for adjusting the detection means. This device is part of alignment equipment 1 for aligning or processing substrates. Alignment equipment 1 can align substrates (not shown) with each other and bond them together at least partially and / or temporarily (so-called pre-bonding).

[0160] The alignment equipment 1 includes a first substrate holder 9, on which a first substrate can be loaded and fixed to the substrate holder surface. The alignment equipment 1 further includes a second substrate holder 11, on which a second substrate can be loaded and fixed.

[0161] In particular, the lower first substrate holder 9 is located on a first moving device 10 for holding the first substrate holder 9 and for supplying and adjusting (aligning) the substrate. In particular, the upper second substrate holder 11 is located on a second moving device 12 for holding the second substrate holder 11 and for supplying and adjusting (aligning) the substrate. The moving devices 10 and 12 are fixed to a common, robust table or frame 8 to reduce / minimize vibrations of the functional components. The frame may, in particular, include an active vibration damper.

[0162] The optical systems 2 and 5 of the alignment equipment 1 can also be used to detect alignment markings on a substrate (not shown). Therefore, the detection means 3 and 6 (especially the optical systems) can also detect alignment markings on the substrate or substrate holder. The optical system 2 is mainly configured to detect adjustment marks in the adjustment marking field.

[0163] The optical system 2, in particular the detection means 3, is capable of focusing on the focal plane or focal position. Here, at least one adjustment mark is detectable within the focal region 19. The horizontal spacing (z-direction) between adjustment marks on different planes of the adjustment marking field is known and, additionally, readable based on the information content of the adjustment marking (e.g., a QR code). Movement of the optical system 2, particularly in the X, Y, and Z directions, is performed by a positioning device 4 for positioning the optical system 2. The positioning device 4 can be fixed in particular to a robust frame 8.

[0164] If the 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 relative to the adjustment mark on the first plane 18 of the adjustment marking field 14. Positioning in the XY direction can be considered similarly, and during adjustment, the table / frame is preferably fixed.

[0165] In the illustrated embodiment of the alignment equipment 1 equipped with the detection unit 3, adjustment marks 15 of the adjustment marking field 14 are further detectable at xyz positions. After refocusing or refocusing to another plane (when the distance between the planes of the adjustment marking field 14 is known), the actual spatial angular position is detected from a known height of the plane, or from a known spacing between the planes of the adjustment marking field, or from parasitic lateral movement of the detection means 3 with the substrate holder 9 fixed. This identifies the wedge error of the optical system 3 and the substrate holder 9, or the housing surface of the substrate holder 9. This allows the optical system 3 to be advantageously adjusted or calibrated relative to the substrate holder 9 based on the adjustment marking field. Furthermore, the position of the detection means 3 is also calculable. This position can be used as a correction factor to reduce the alignment error of the substrate stack. A substrate (not shown) is housed on a substrate holder surface 20 which consists of a plurality of individual surfaces. The substrate housing surface 20 preferably consists of a plurality of protrusions 21.

[0166] In the illustrated embodiment of the alignment equipment 1, the measurement system 5 or detection unit 6 can further detect, with particularly high accuracy, the XY position and / or orientation (including rotational orientation) and / or height position of the lower substrate holder 9.

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

[0168] In a preferred embodiment of this device, although not shown, the following exemplary steps can be carried out: The first substrate is fixed to the substrate holder surface of the first substrate holder 9. For fixing, mechanical clamps and / or electrostatic clamps are used in particular, or a pressing force formed due to the pressure difference between the ambient environment of standard atmosphere and the negative pressure in the first substrate holder 9, also known as vacuum fixing. This fixing is carried out in particular to prevent the first substrate from moving inaccurately or undesirably 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, coefficients of thermal expansion, thermal expansion can be prevented or reduced, and the difference in the coefficients of thermal expansion and / or the linear difference in the coefficients of thermal expansion is preferably less than 5%, more preferably less than 3%, and particularly preferably less than 1%.

[0169] This equipment is preferably operated in a temperature-stabilized ambient environment, particularly in a cleanroom, where the temperature fluctuation during the adjustment or alignment cycle is less than 0.5 Kelvin, preferably less than 0.1 Kelvin, particularly preferably less than 0.05 Kelvin, and 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 moving the first substrate, and these are designed so that they cannot move relative to each other.

[0171] This substrate fixing can be performed by shape coupling and / or preferably by force coupling. The quasi-monolithic coupling reduces, preferably by at least an order of magnitude, and particularly preferably eliminates, any influence that could cause displacement and / or torsion and / or deformation between the substrate holder and the substrate. Therefore, along with the adjustment of the detection means 3 relative to the substrate holder, the alignment error can be further reduced.

[0172] The substrate and the substrate holder 9 can be joined by shape coupling or force coupling, in particular to suppress differences in thermal expansion. Furthermore, the substrate holder can reduce, eliminate, and / or correct the substrate's own deformation. In addition to these means, at least one detection means is provided at a predetermined position and angle relative to the substrate holder, particularly with respect to the adjustment markings of the adjustment marking field on the surface of the substrate holder, thereby enabling, on the one hand, detection and correction of slow thermal relative movement, and on the other hand, by pre-adjusting the position and angle of the detection means, at least the positioning error of the substrate holder relative to the detection means can be reduced.

[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 while detecting the first adjustment mark 15 of the adjustment marking field 14.

[0175] Preferably, a detection unit, or equivalent detection means, is positioned aligned with or perpendicular to a predetermined adjustment mark in the adjustment marking field 14, thereby eliminating the need to reposition the substrate holder and / or detection means to detect the alignment marking of the substrate to be bonded at the same xy position. This improves the accuracy of substrate stack alignment by reducing the required movement, detection, and adjustment.

[0176] The lower substrate holder has adjustment marks 15 in the adjustment marking field 14. Based on the adjustment marks 15, the XYZ position and alignment point of each adjustment mark 15 within the adjustment marking field can be further identified. In this case, by detecting another adjustment mark 15 in a different plane of the same alignment marking field 14, the wedge error or angular position of the substrate holder 9 can be detected relative to the detection means 3.

[0177] One possible solution is for the substrate holder 9 to move relative to the detection means 3 in the Z direction, thereby fixing the detection means in place, instead of the detection means 3 moving relative to it. From this adjustment process, it is possible to calculate similar correction values ​​for relative positions, particularly to identify parasitic movement of the substrate holder relative 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 adjustment marks 15 on different planes of the adjustment marking field 14.

[0179] The measured values ​​(XY position and / or alignment point of the first substrate, and the XYZ position and / or alignment point of the first substrate holder 9 or the first substrate) can be correlated with each other after adjustment / correction is applied, thereby allowing the XYZ position of the substrate holder 9 and / or detection means to be reproducibly restored. This allows the substrate fixed to the substrate holder 9 to be moved in a closed-loop control for alignment and setting the bonding interval without directly observing the adjustment marking 15 on the substrate holder 9 or the alignment marking of the substrate.

[0180] By associating the position of the substrate with the spatial position and / or location of the substrate holder 9 or detection means 3, alignment can be achieved without directly observing the XYZ position and / or alignment location and / or relative angular position of each substrate during alignment and / or contact. The obtained correction value reduces positioning uncertainty before or during alignment and contact between the first and second substrates, thereby improving positioning accuracy. Furthermore, the distance between the substrates can be set and / or minimized during alignment, and for this purpose, an additional adjustment marking field can be used on the back surface of the substrate holder, particularly facing away from the substrate housing surface.

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

[0182] This backlash arises from the movement of the moving device, but only the detection point changes, and as a result, the measured quantity exists as a relative alignment error. This method reduces local positioning inaccuracy by locally measuring the incorrect position of the detection means 3, and therefore, the local alignment error is further reduced by the reduced accuracy of this local positioning inaccuracy.

[0183] To further improve alignment accuracy, the first detection unit 3 can be operated in time synchronization with at least one 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, most preferably less than 100 milliseconds, even more preferably less than 10 milliseconds, most preferably less than 1 millisecond, and in the ideal case, simultaneous. This is particularly advantageous because it eliminates the effects of disruptive noise, such as mechanical vibrations. Mechanical vibrations propagate within materials, particularly as solid-borne sound at several thousand m / s. If the closed-loop control and detection means operate faster than the propagation speed of solid-borne sound, the disruptive noise is reduced or eliminated.

[0184] When detection units 3 and 6 are synchronized with each other (particularly by simultaneous triggering of detection and adjustment of detection time, and / or the same integration time for the camera system) to detect the adjustment marking field 14 and another adjustment marking on the back of the substrate holder, some faulty effects can be reduced, and in the best case, eliminated. This is because detection should occur at the point where the faulty effects have the least possible impact on detection accuracy.

[0185] In one preferred embodiment of the present method and apparatus for adjusting detection means, and in the apparatus for adjustment, detection is performed synchronously, particularly at the peak of vibration, especially when periodic disturbance effects are known. Advantageously for this purpose, vibration sensors (accelerometers, interferometers, vibrometers) can be pre-installed at points in the apparatus where accuracy is critical. Disturbance effects are recorded by these vibration sensors and considered or processed by calculation for elimination. In another embodiment, vibration sensors can be fixedly integrated at characteristic points in the equipment.

[0186] It is advantageous for adjusting the above-described detection means, or possibly multiple detection means, when the adjustment marking field 14 is fully measured and target values ​​are prepared in a memory device for comparison or difference formation. These target values ​​include, in particular, 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 a trajectory for optimally approaching a spatial position, and / or, in particular, machine-readable values ​​for the drive unit, especially for focusing the detection means approach 3. In other words, the locations of individual adjustment marks in one adjustment marking field and other adjustment marks in another adjustment marking field are known and stored.

[0187] Figure 2a shows multiple adjustment marking fields in a schematic, greatly enlarged plan view, each with one exemplary selected and visible adjustment mark 15 or adjustment marking 15.

[0188] Each adjustment mark 15 symbolically and schematically represents an absolute and unique coding of the position and location of each individual adjustment mark or adjustment marking 15. Each adjustment mark 15 or adjustment marking 15 may be located on different planes of the adjustment marking field. Since the xyz positions of each alignment marking 15 are known, detecting the coded adjustment marks 15 or adjustment marking 15 is sufficient for detecting the position of a substrate holder (not shown). This allows for refocusing (or relative movement in the z direction at the same focus) to another adjustment mark 15 or adjustment marking in the same adjustment marking field, thereby allowing for the identification of the angular position / wedge error of the detection means relative to the substrate holder. Therefore, adjustment of the detection means can be advantageously performed based on the adjustment marking field.

[0189] Figure 2b shows an adjustment marking field 14'' having different layers 16, 16' or steps. Thus, the adjustment marks on one step are located on one plane and have a specific and known spacing from the other step or plane of the adjustment marking stage field 14''. In the illustrated embodiment, the adjustment marking field 14'' is located between the raised or protruding portions 21'.

[0190] The adjustment marking field 14'' is positioned in a fixed location relative to the substrate holder or the substrate holder surface 20. Here, the mounting surface of the raised portion 21' (for housing the substrate) is higher than the highest point of the adjustment marking field 14'' or has a greater gap with respect to the substrate holder surface. Therefore, the adjustment marking field is positioned below the substrate holder housing surface (the mounting surface of the raised portion). This advantageously prevents the adjustment marks or adjustment markings (on the uppermost plane of each adjustment marking field) from contacting the substrate.

[0191] The reduced mounting surface of the protrusion 21' prevents the entire substrate from being placed on it, thereby preventing distortion caused by particles present on the back surface of the substrate, which may occur in some cases. This advantageously minimizes cross-contamination of the substrate or substrate holder.

[0192] This adjustment marking field is positioned fixedly relative to the substrate holder. In particular, the adjustment marks are located in the field of view or focal area of ​​the detection unit 3, and are therefore detectable, on different planes or multiple steps and / or layers 16, 16'. Since the step heights or the spacing between planes are known, and the positions of the adjustment markings are known, these can be used to determine the angular error of the detection means to be refocused.

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

[0194] The spacing 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 spacing between the planes is 50.00 micrometers.

[0195] Furthermore, it is advantageous that each additional adjustment mark 15, 15' has detectable location information. Multiple adjustment fields between the raised / protruding portions 21, 21' make it possible to identify the angular position or wedge error between the substrate holder and the detection means at many corresponding locations without having to move the detection means in the xy direction. Since the locations of the detected adjustment marks 15, 15' relative to the adjustment mark 15 of the adjustment marking field are known, this location and location information can be used to optimize movement or to set intervals, particularly bonding gaps. Preferably, not only are the locations of the detected adjustment marks 15, 15' relative to the adjustment marks 15, 15' on the same plane known, but the locations of the detected adjustment marks 15, 15' on each plane relative to other planes of the adjustment marking field are also known.

[0196] Figure 3 shows a portion of one possible embodiment of the adjustment marking field 14'', with each exemplary adjustment mark 15' supplemented by a machine-readable code. Here, each adjustment mark 15 may be located on a different plane (stage and / or layer), and the code may include information about which plane each is on. Furthermore, the code may include unique information about the location and position of each adjustment mark 15'.

[0197] Figure 4 illustrates a cross-sectional view of one embodiment of the adjustment marking field 14''''. The adjustment marks 15' of the adjustment marking field 14'''' are arranged on three distinct planes 18, 18', 18'' and are detectable by the detection unit 3. Here, the detection unit 3 can detect only the adjustment marks 15' within the focal region 19. To detect adjustment markings arranged above and below distinct planes, the detection unit 3 may also use electromagnetic beams of distinct wavelengths. In this case, the adjustment marking field is correspondingly at least partially transparent to these distinct wavelengths.

[0198] The first plane 18 has a known interval 17'' with respect to the second plane 18'. The second plane 18' similarly has a known interval 17' with respect to the third plane 18''. Furthermore, the interval 17 between the first plane 18 and the third plane 18'' is known. The intervals 17'' and 17' are of different magnitudes in the illustrated embodiment, so that when using the adjustment marking field 14'''' for adjusting the detection means, it is possible to approach or set all three intervals 17, 17', and 17', respectively. This makes it possible to detect different intervals between the detection means 3 and the adjustment marking. At the same time, it is possible to favorably approach known intervals with respect to other planes.

[0199] The combination of intervals 17, 17', 17'' can also be approached by moving the fixed substrate holder 9 multiple times relative to the adjustment marking field 14''', and this movement can be performed as a focusing movement of the detection means 3. For example, the focused interval 17'' can be set first, and then the position can be moved further towards the interval 17' in the same direction. Alternatively, for example, the substrate holder can be moved by twice the interval 17''. For this purpose, alignment is performed in two steps, and the detection unit is set accordingly between these steps, because the focal position of the detection unit 3, and thus the focal area 19, is adapted to the detection unit 3.

[0200] Figures 5a and 5b show the optical system 3 at the first position 23 and at the second position 24 (after adjustment). The wedge error (angle 22) between the optical system 3 and the substrate holder, i.e., the 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 at the first position 23 and is compensated for or no longer present at the second position 24. Thus, the optical system 3 is advantageously adjustable based on the detection of two adjustment markings on 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 back surface of the substrate holder, additional detection means 7. Positioning device for additional measurement systems 8 frames, table 9. PCB holder, first PCB holder (to be aligned) 10. Moving device for the substrate holder to be aligned. 11. Second substrate holder 12 Second moving device 13. Substrate deformation device 14,14',14'',14'''' Adjustment marking field, alignment marking field 15,15' Adjustment marks, adjustment markings, reference markings 16,16' Adjustment marking field layer 17,17',17'' Spacing between adjustment marks placed vertically. 18,18',18'' Plane of the adjustment marking field 19 Focal area of ​​detection means, focal area of ​​optical system 20 Surface of substrate holder 21,21' Raised portion, pin, projection 22. Angle, wedge error 23 1st position 24 2nd (adjustment) position 25 Optical axis

Claims

1. A device for adjusting the detection means (3, 6), i) A substrate holder (9) for housing the substrate, ii) At least one adjustment marking field (14, 14', 14'', 14'''') having adjustment marks (15, 15') positioned in a fixed position relative to the substrate holder (9), iii) The detection means (3, 6) for detecting the adjustment marks (15, 15'), In an apparatus having at least, The detection means (3, 6) is adjustable relative to the substrate holder (9) based on the adjustment marks (15, 15') positioned above and below the adjustment marking fields (14, 14', 14'', 14'''), the substrate holder (9) has regularly arranged raised portions (21, 21') on the substrate holder surface (20) to provide a substrate housing surface, and the plurality of adjustment marking fields (14, 14', 14'', 14''') each having an adjustment mark (15, 15') are arranged between the raised portions (21, 21') and are regularly offset from each other, the apparatus.

2. The apparatus according to claim 1, wherein the adjustment marks (15, 15') of the adjustment marking field (14, 14', 14'', 14''') are arranged on a first plane (18, 18', 18'') and a second plane (18, 18', 18''), 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'') are spaced apart from each other (17, 17', 17'').

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

4. The apparatus according to any one of claims 1 to 3, wherein the detection means (3, 6) is adjustable by changing the focus of the detection means (3, 6).

5. The apparatus according to claim 2, wherein the adjustment marks (15, 15') on the first plane (18, 18', 18'') and the adjustment marks (15, 15') on the second plane (18, 18', 18'') are arranged to be vertically aligned.

6. The apparatus according to claim 2, wherein the adjustment marks (15, 15') on the first plane (18, 18', 18'') and the adjustment marks (15, 15') on the second plane (18, 18', 18'') are arranged to be vertically and regularly offset from each other.

7. The apparatus according to claim 2, wherein the adjustment marks (15, 15') on the first plane (18, 18', 18'') and the adjustment marks (15, 15') on the second plane (18, 18', 18'') are offset from each other in a stepped manner and arranged on different layers (16, 16').

8. The apparatus according to any one of claims 1 to 7, wherein each of the adjustment marks (15, 15') additionally has individual information content that can be detected by the detection means (3, 6).

9. The apparatus according to any one of claims 1 to 8, wherein the detection means (3, 6) is an optical detection means, in particular an optical system having a determinable optical central axis.

10. The apparatus according to claim 2, wherein the first plane (18, 18', 18'') and / or the second plane (18, 18', 18'') of at least one of the adjustment marking fields (14, 14', 14'', 14''') is placed on the substrate holder surface (20).

11. The apparatus according to any one of claims 1 to 10, wherein at least one of the adjustment marking fields (14, 14', 14'', 14''') is fully fitted into the substrate holder (9), and the substrate holder (9) is positioned at least partially below the substrate holder surface (20).

12. The apparatus according to any one of claims 1 to 11, wherein the detection means (3, 6) can be used to read alignment markings on a substrate.

13. A method for adjusting the detection means, i) A step of preparing the substrate holder (9) which is positioned in a fixed position relative to the substrate holder (9) and has an adjustment marking field (14, 14', 14'', 14'''') with adjustment marks (15, 15'), ii) The step of adjusting the detection means (3, 6) relative to the substrate holder (9), A method having, A method characterized in that the detection means (3, 6) are adjusted based on the adjustment marks (15, 15') of the adjustment marking fields (14, 14', 14'', 14''') arranged vertically, the substrate holder (9) has regularly arranged raised portions (21, 21') on the substrate holder surface (20) to provide a substrate housing surface, and a plurality of adjustment marking fields (14, 14', 14'', 14''') each having an adjustment mark (15, 15') are arranged between the raised portions (21, 21') and are regularly offset from each other.

14. The adjustment of the detection means in step ii) is performed in the following steps, in the following order, namely: a) A step of detecting a first adjustment mark on the first plane (18, 18', 18'') of the adjustment marking field (14, 14', 14'', 14''''), b) A step of detecting a second adjustment mark on the second plane (18, 18', 18'') of the adjustment marking field (14, 14', 14'', 14''''), c) A step of determining the wedge error between the detection means (3, 6) and the substrate holder (9), d) A step of compensating for the wedge error obtained in step c), It has, The method according to claim 13, 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'') are spaced apart from each other (17, 17', 17'').

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