Substrate holder, method for producing a substrate holder of this kind, and method for holding a substrate

Abstract

The invention relates to a substrate holder (1) for holding a substrate (7) during a processing operation, for example during a bonding operation, lithography operation, coating operation or cleaning operation, wherein: the substrate holder (1) comprises a separating region (4) for separating regions with different pressure levels which are established between the substrate holder (1) and the substrate (1) when the substrate (7) is held; the separating region (4) comprises a sealing device (5, 5', 5'', 5''') and a pin element (6) and / or a further pin element (6'); the pin element (6') and / or the further pin element (6') and the sealing device (5, 5', 5'', 5''') are designed such that, in order to form a contactless sealing region, the pin element (6) and / or the further pin element (6') prevents, at least in portions, contact between the sealing device (5, 5', 5'', 5''') and the substrate (1') in the separating region (4) when the substrate (1) is held.

Description

[0001] Substrate holder, method for producing such a substrate holder and method for holding a substrate

[0002] The present invention relates to a substrate holder, a method for producing such a substrate holder and a method for holding a substrate.

[0003] Bonding technology has evolved significantly in recent years and decades. A key driver for this advancement was the desire to produce individual functional units on different substrates, especially wafers, and to bond them together using a single bonding process. This allowed different manufacturers to produce different substrates with different functionalities, which could then be combined using a single bonding process.

[0004] Fundamentally, there are different types of bonding processes. A bonding process is a temporary bond in which a bonding adhesive, for example a polymer, is preferably used to connect a first substrate, the product substrate, to a second substrate, a carrier substrate. This bonding process is usually employed to transport the product substrate and stabilize it for further processing steps. Processes are carried out on the product substrate that result in the product substrate being exposed to chemical, mechanical, and thermal stress. If the product substrate were not stabilized by the carrier substrate, it would curl, break, or crack. After the product substrate has been successfully processed, it can be separated from the carrier substrate using one of many debonding processes.

[0005] Another bonding technique is direct bonding. In direct bonding, two substrates are directly connected via their substrate surfaces. In most cases, dielectric substrate surfaces that are hydrophilic or hydrophobic are used. This type of direct bonding is known as fusion bonding. If the substrate surfaces do not have a continuous dielectric surface, but are interrupted by metallic areas, such as through-silicon vias (TSVs), they are also referred to as hybrid bond surfaces. Fusion bonding techniques have by far achieved the greatest technological advances in recent years, as they have made it possible to implement heterogeneous integration.

[0006] One of the most important tools for performing a direct bond is a substrate chuck. The substrate chuck has also undergone numerous developments over the past decades.

[0007] Initially, the substrate holder consisted of a component or a group of components with a flat substrate holder surface. This substrate holder surface could contain fixation elements, such as electrodes or vacuum holes, depending on whether the substrate holder was designed as an electrostatic or vacuum substrate holder. The characteristic feature, however, was the flat substrate holder surface, interrupted at most by fixation elements.

[0008] A first development consisted of designing the substrate holder so that the substrate to be fixed rests on a multitude of pin elements (English: pins), sometimes also called studs. Instead of a pin element substrate holder, one could also speak of a stud substrate holder. In the following text, the word pin element (instead of stud element) will be used to describe this component of the substrate holder. The pin elements are generally raised portions that can have different dimensions and shapes. Most of the time, the pin elements are cylindrical with a small ratio of cylinder axis length to cylinder diameter. This compact shape is intended to guarantee stability. The substrates are usually fixed using vacuum fixation. On a base plane on which the pin elements are located, there are through-holes to a vacuum system inside the substrate holder.Through appropriate evacuation, the space between the base plane and the substrate—that is, the space between the pin elements—can be evacuated. Atmospheric pressure then presses and fixes the substrate onto the pin elements. One of the reasons for developing a pin element substrate holder was to prevent backside contamination of the substrate. The smaller the contact surface, the fewer particles can be transferred from the substrate holder to the backside of the substrate.

[0009] A further development of the substrate holder was the so-called zone substrate holder. These zone substrate holders are usually also pin element substrate holders, but are characterized by the fact that there are different areas on the substrate holder, called zones, which are separated from other zones by a sealing device. The fixing elements of such zone substrate holders are usually also vacuum fixing devices. Each zone can switch its fixing, in particular its vacuum fixing, on and off independently of the fixing of the other zones. This makes it possible to selectively fix a substrate as a function of location. It is even possible to determine the fixing strength, i.e., the pressure with which the substrate is pressed onto the substrate holder surface (in the case of a pin element substrate holder, the pin element surfaces), through the strength of the fixing, in particular the level of the negative pressure generated.This control option is fundamentally important for influencing the bond wave that forms and moves between two substrates, which has been proven to have a very strong influence on the bonding result. The ability to control the different zones can significantly improve the bonding result.

[0010] Based on this, a problem has emerged with pin element substrate holders, especially with zone substrate holders, that the topography of the pin elements and / or the sealing devices affects the bonding result. The topography of the pin elements and / or the sealing devices can be detected by measuring systems through mechanical deformation and / or plastic deformation and / or changes in the bonding interface and / or run-out errors. However, the desired bonding result would be a homogeneous, defect-free bond.

[0011] One way to solve this problem was to reduce the spacing between the pin elements, i.e. to increase the number of pin elements per unit area, and thus the pin element areal density. Due to the reduced spacing between the pin elements, the substrate support is better and the substrate lies flatter on the pin elements. However, if the spacing between the pin elements is too small, it is no longer possible to produce appropriate sealing devices between the pin elements, which prevents the production of a zone substrate holder because different pressure levels cannot be maintained. In the prior art, the problem is solved by simply omitting the pin elements along a contour line in order to be able to insert the sealing device. This in turn leads to a disruption of the homogeneity of the pin element areal density.It is an object of the present invention to provide a substrate holder which, when holding the substrate, eliminates as far as possible a falsification of a processing result due to the effect of pin elements and / or sealing devices and at the same time ensures that a spatially resolved influence on the holding is possible.

[0012] The present invention solves this problem with a substrate holder according to claim 1, a method for producing the substrate holder according to claim 14, and a method for holding a substrate according to claim 15. Advantageous developments of the invention are specified in the subclaims. The scope of the invention also includes all combinations of at least two features specified in the description, the claims, and / or the drawings. For specified value ranges, values ​​within the specified limits are also to be considered disclosed limit values ​​and can be claimed in any combination.

[0013] According to a first aspect of the present invention, a substrate holder is provided for holding a substrate during a processing operation, for example during a bonding operation, lithography operation, coating operation and / or cleaning operation, wherein the substrate holder has a separation region for separating regions with different pressure levels which arise between the substrate holder and the substrate during holding, wherein the separation region has at least one sealing device and a pin element and / or a further pin element, wherein the pin element and / or the further pin element and the sealing device are designed such that, in order to form a contactless sealing region, the pin element and / or the further pin element at least partially prevents contact in the separation region between the sealing device and the substrate when holding the substrate.

[0014] In contrast to the substrate holders known from the prior art, the invention provides that the sealing device in the separation area at least partially, preferably over the entire separation area or over more than 30%, preferably more than 50% and particularly preferably more than 70% of the separation area, establishes no contact with the substrate, in that the pin elements and / or further pin elements keep the substrate at a distance from the sealing device while being held. At the same time, the sealing device ensures that different pressure levels can be generated in the area adjacent to the separation area by forming a contactless sealing area. A sealing device or a sealing element is therefore to be understood as such a structural or physical measure which, in particular volume-filling, serves to form a sealing labyrinth or a gap seal, i.e.to increase a flow resistance in the separation area. In particular, a flow resistance is increased by the arrangement of the pin element, another pin element and / or sealing device. For this purpose, for example, the arrangement of the sealing device influences a length of the flow path and / or a shape of the flow path. The separation area is therefore to be understood in particular as one that is suitable for maintaining different pressure levels without, for example, realizing a completely hermetic sealing device. Rather, the separation area serves to ensure that an intended pressure level can be maintained, supported and / or realized in the areas adjacent to the separation area. This is therefore not about a completely hermetic sealing of two areas by the separation area.

[0015] By deliberately spacing the substrate from the sealing devices or the sealing device, it is advantageously possible to prevent the substrate from contacting the sealing device over a large area, in particular over a relatively large area. This advantageously further reduces the influence of the substrate holder on the substrate, whereby the machining process is less influenced by the sealing device. At the same time, pin elements, further pin elements and the sealing device interact in such a way that the flow resistance between the areas with different pressure levels increases, thus achieving a desired sealing effect. The advantage here is that the sealing devices themselves no longer act mechanically on the substrate. A sealing surface, in contrast to a pin surface, i.e.a support surface for the pin element or other pin elements, and does not come into contact with the substrate. Measurements have shown that the comparatively wide sealing devices in particular have such an impact on the bonding interface during the bonding process that the impact becomes subsequently visible through measuring instruments. Due to the recessed sealing devices, these do not come into contact with the substrate in the first place.

[0016] In particular, it is provided that the substrate holder extends substantially along a main extension plane and the sealing device, the pin element and / or the further pin element are designed as elevations which protrude in a direction running perpendicular to the main extension plane. In particular, it is preferably provided that the substrate holder has a preferably imaginary base plane running substantially parallel to the main extension plane, from which the pin elements, the further pin elements and / or sealing devices protrude in a direction running perpendicular to the main extension plane. The bearing surfaces of the pin element or the further pin element preferably run parallel to the base plane or main extension plane. It is conceivable that a side of the sealing device facing the substrate when held runs obliquely to the main extension plane and / or has an uneven profile.This allows for greater design freedom for the sealing devices, as parallel alignment is no longer required for contact. In the areas formed between the substrate and the base plane when holding the substrate, a type of sealing labyrinth, labyrinth seal, or gap seal is provided, particularly through the respective arrangement of the pin elements, the additional pin elements, and / or the sealing devices, which is particularly suitable for ensuring different pressure levels in the areas adjacent to the sealing area or separation area. It is therefore proposed to dispense with direct contact between the sealing devices and the substrate and to construct a combination of pin elements and sealing devices as a labyrinth seal.

[0017] The described substrate holder is preferably used for a bonding process, in particular fusion bonding, most preferably for hybrid bonding. However, the use of the substrate holder is in no way limited to bonding. The substrate holder can also be used to fix a substrate intended for lithography, in particular photolithography or imprint lithography. Applications for coating processes, cleaning processes, and / or similar processes are conceivable.

[0018] It is conceivable for the sealing device to be inserted between the pin elements without removing pin elements. In this way, a pin element areal density, i.e. a number of pin elements per unit area, can be achieved. The sealing device is preferably set back. It is conceivable, for example, for a sealing device to be integrated into an existing arrangement, for example retrospectively. In this way, sealing can be increased and / or separation into individual zones is also possible retrospectively. This makes it possible to retrofit holding devices accordingly. It is preferably provided that the pin element and / or the further pin element protrudes relative to the sealing device. In this way, it can be ensured with comparatively simple means that no contact is caused between the substrate and the sealing device.In particular, the support surfaces of the pin elements and / or other pin elements lie in a common plane running parallel to the main extension plane.

[0019] Preferably, the additional pin element is integrated into the sealing device. This has the advantage that when designing the separation region, i.e. the arrangement of the pin elements and the sealing device, no choice has to be made between the pin elements and the sealing devices for their positioning. It is therefore possible to construct both in any number, distribution, and size. The pin elements are preferably arranged on a hexagonal lattice. However, square, centered-rectangular, rectangular, and oblique-angled lattices are also conceivable. These lattice types are known from crystallography and group theory. A non-symmetric, i.e. statistical, distribution of the pin elements is also conceivable, although not preferred. The hexagonal lattice is preferred because it guarantees that each pin element is the same distance from its nearest neighbor.It is thus advantageously possible to increase the density of the pin elements or additional pin elements in the separation area, since the area or a surface of the sealing device is also utilized. This allows for increased homogeneity in the distribution of support surfaces provided by the pin elements and additional pin elements, since the sealing devices no longer obstruct the placement of the pin element or additional pin element in this area. This allows for homogeneity of the pin element density to be achieved, making it possible to manufacture sealing devices in any desired shape, in any desired position, and in any desired number.

[0020] In this case, integration is to be understood in particular as meaning that the further pin element is arranged, for example, on the sealing device or that the further pin element is surrounded by the sealing device and is preferably embedded in a recess, particularly preferably in a blind bore, in the sealing device. For example, it is conceivable for the sealing device to be strip-shaped or annular strip-shaped. Preferably, several strip-shaped sealing devices run parallel to one another in the separation region. In this case, it is particularly preferred that one row or several rows of pin elements be arranged between the sealing devices, which run or run essentially parallel to the sealing device. The further pin elements are, for example, embedded in this strip-shaped or annular strip-shaped sealing device.As a result, the area in which the sealing device itself is arranged can advantageously already be used as a position for a pin element, namely the further pin element.

[0021] Preferably, the substrate holder comprises a first zone and a second zone, the first zone being separated from the second zone by the separation region. This makes it possible, for example, to implement different pressure levels in the regions assigned to the first and second zones, the separation region between the first zone and the second zone ensuring that at least the pressure level between the regions separated by the separation region is not immediately equalized again. It is conceivable that, in order to maintain the pressure level during holding, appropriate vacuum sources or compressors ensure that the zones are subjected to an appropriate negative pressure, in particular different negative pressures, in order to generate and / or maintain different pressure levels.The separation area essentially supports the different pressure levels to fulfill the desired purpose of fixing or releasing specific areas of the substrates.

[0022] It is preferably provided that the separation area has a plurality of sealing devices, in particular each with at least one further pin element, to form a sealing labyrinth, wherein the sealing devices are arranged one behind the other along a direction running from the first zone to the second zone. The substrate holder will therefore generally have vacuum leaks between the individual zones, which can preferably be reduced by connecting a plurality of sealing devices in series to such an extent that suction of the substrate is possible or simplified in a targeted and controlled manner. It is conceivable that different sealing devices and / or further pin elements are implemented. This can support the maintenance of the various pressure levels.It has proven particularly advantageous to implement or arrange at least three sealing devices, preferably at least five sealing devices, and particularly preferably at least eight sealing devices, between the first and second zones along the specified direction. It is conceivable that there are different sealing devices between different zones. For example, one could imagine that, viewed in the radial direction from a center of the substrate holder, the number of sealing devices, pin elements, and / or further pin elements per separation area increases and / or decreases.

[0023] The substrate holder thus preferably has a plurality of zones. The zones can be arbitrarily shaped and separated by the sealing devices or separation areas described in this disclosure. Zone substrate holders are known in the prior art and will not be described in detail here. Some substrate holders with zones are disclosed and described in the publications WO 2022 002 345 A1, WO 2019 057 286 A1, and WO 2018 028 801 A1, to whose disclosure content explicit reference is made in this regard.

[0024] In particular, it is provided that the separation region has a self-contained course, for example a frame-shaped course. For example, an arc-shaped, (partially) segment-shaped or circular course is preferred. The sealing device preferably extends substantially along the course of the separation region. This makes it possible, for example, to separate zones or regions with different pressure levels arranged concentrically to a center of the substrate holder. This makes it possible, for example, to control a bond wave course in the radial direction, especially if this begins in the center of the substrate holder. It would also be conceivable for the separation region to surround a zone that forms a segment in an arrangement of segments arranged in a checkerboard pattern. For example, the checkerboard-like arrangement in a row can follow a specific course, for example a circular course.This allows, for example, different effects on the bond wave to be achieved at the same radial distance from the center of the substrate age, but at different positions in the circumferential direction. This allows for even more precise corrections when holding the substrate, especially during a bonding process in which a bond wave is generated.

[0025] Preferably, a lateral extent of the sealing device is greater than a lateral extent of the further pin element. In particular, the lateral extent is measured, for example, as a cross-section, i.e., cross-sectional area, in a direction and / or plane running parallel to the main extension plane. This ensures that a support surface assigned to the further pin element in the region of the sealing device is smaller than the extent of the sealing device. Preferably, the lateral extent is more than three times, preferably more than ten times, or even more than 20 times as large as the lateral extent of the pin element.

[0026] Preferably, the pin element and / or the further pin element and the sealing device or preferably the substrate holder are designed to be monolithic, in particular to more than 50%, preferably more than 70% and particularly preferably substantially completely. Monolithic is also understood to mean, in particular, the one-piece or integral design of the substrate holder. The component of the substrate holder which fixes the substrate is thus preferably constructed monolithically. The term substrate holder is understood to mean, in particular, the structural measures, without, for example, vacuum sources, which are connected to the substrate holder. The substrate holder can be referred to as a fixing component. In general, a substrate holder must be thought of as a component group with several associated components.However, since most of the other components of the substrate holder do not provide any significant added value for the inventive concept, the term "fixing component" can also be used synonymously with "substrate holder." Monolithic means that the pin elements and the sealing devices are not inserted, but rather machined from a solid component. Monolithic, integral, or one-piece design specifically means that no further disassembly of the substrate holder is possible without destroying it. Any type of manufacturing technology can be used for this purpose. Although the monolithic design is preferred, the substrate holder can also be constructed so that the pin elements and / or the sealing devices can be inserted, for example, in the form of a kit. This design allows, in particular, the pin elements and / or the sealing devices to be manufactured from a different material than the fixing component or base body.

[0027] It is particularly preferably provided that a plurality of further pin elements are integrated in a common sealing device. This means that a common sealing device can be used for a plurality of further pin elements. This proves to be advantageous, for example, for the production of the substrate holder, since additional individual elements do not have to be produced. Furthermore, this contributes to the stability of the substrate holder. The further pin elements in the common sealing device are preferably arranged along a row, which particularly preferably essentially follows the direction of travel of the sealing device, in particular if the sealing device is in the form of a strip. It is also conceivable that a plurality of rows of further pin elements are integrated into the sealing device. In this case, it is conceivable that in the radial direction orin a direction perpendicular to the course of the separation area, the further pin element is arranged centrally or offset from the center of the sealing device.

[0028] Furthermore, it is preferably provided that respective pin spacings between adjacent pin elements or further pin elements on the one hand and further pin elements or pin elements on the other hand are essentially constant along a predetermined direction. This makes it possible to achieve a homogeneous distribution of the support surfaces provided by the pin elements and / or further pin elements, at least in the predetermined direction. Particularly preferably, the predetermined direction runs along a direction that extends parallel to the planned bonding direction or perpendicular to the course of the bonding wave. This simplifies monitoring, for example during a bonding process. The pin element spacing is preferably the quantity to be reduced. In particular, the support surfaces provided by the pin elements and / or further pin elements are arranged uniformly, in particular equidistantly, from one another along the predetermined direction.

[0029] The pin elements and / or other pin elements have at least three geometric parameters: a pin element diameter or a pin element cross-section, a pin element height and a pin element pitch.

[0030] It is preferably provided that a pin element spacing is between 0.1 mm and 10 mm, preferably between 0.2 mm and 5 mm, even more preferably between 0.5 mm and 2.5 mm, most preferably between 1.0 mm and 2.0 mm, and most preferably approximately 1.5 mm. This results in the advantage that by reducing the pin spacing in this way on the substrate holder by means of a pressure difference, substrates fixed locally are deflected less. As the pin spacing becomes smaller, the surface is thus increasingly approached to a full, ideal, flat surface. This has a positive influence on the machining process. The substrate holder is designed so that the pin element spacing can be achieved as small as possible. The pin element spacing is interpreted in particular with regard to the grid used to produce the pin elements.

[0031] If the pin elements are manufactured along a square grid, the pin element spacing is preferably understood as the distance between the pin elements along the perpendicular sides of the square. Therefore, the pin element spacing is preferably not interpreted as the distance between two pin elements along the diagonal of a square.

[0032] If the pin elements are manufactured along a hexagonal grid, which is the preferred embodiment, the pin element spacing is the distance between one pin element and its six nearest neighbors. In this case, the highest possible symmetry is achieved.

[0033] If the pin elements are manufactured along a centered rectangular, right-angled or oblique-angled grid or if the pin elements are even distributed at random positions, only a statistical interpretation of the pin element spacing makes sense.

[0034] The pin element spacing is preferably approximately equal in all directions. In particular, the skilled person understands "approximately" to mean that the difference between two pin element spacings is less than 10%, preferably less than 5%, even more preferably less than 1%, most preferably less than 0.1%, most preferably less than 0.01%. It is also conceivable that the pin element spacing between pin elements in the tangential or circumferential direction differs from the pin element spacing of the pin elements in the radial direction. In particular, it is conceivable that the pin element positions are distributed along a hexagonal grid, which would result in a high degree of symmetry.

[0035] For a pin element that deviates from cylindrical symmetry, the term pin element diameter is used synonymously for a typical geometric dimension of the pin element's cross-section. For example, if the pin element has a square cross-section, the pin element diameter can be understood as either the diagonal length or its side length. Analogous considerations apply to other geometric cross-sections. It is also conceivable for the pin elements to have a pin element diameter that decreases from bottom to top, for example if the pin elements are manufactured as a cone. The pin element diameter or cross-section is a measure of its width. The pin element height describes the distance from the base plane to the pin element surface, i.e. the bearing surface. The ratio between pin element height and pin element diameter should not be too large in order not to exceed Euler's buckling load.

[0036] The pin element diameter is between 0.01 mm and 5.0 mm, preferably between 0.05 mm and 1.0 mm, more preferably between 0.075 mm and 0.75 mm, most preferably between 0.1 mm and 0.5 mm, most preferably about 0.3 mm.

[0037] The pin element height is between 0.01 mm and 2 mm, preferably between 0.02 mm and 1.5 mm, more preferably between 0.025 mm and 1.0 mm, most preferably between 0.03 mm and 0.5 mm, most preferably between 0.1 mm and 0.15 mm.

[0038] The sealing device has at least three geometric parameters: a sealing device width, a sealing device height, and a sealing device offset. The sealing device width describes the width of the sealing device.

[0039] The sealing width describes the width of the sealing device, in particular measured along a radial direction from the center of the substrate holder. The sealing device width is between 0.01 mm and 10 mm, preferably between 0.05 mm and 7.5 mm, even more preferably between 0.075 mm and 5.0 mm, most preferably between 0.1 mm and 1.0 mm, and most preferably approximately 0.5 mm. The sealing device width can be wide enough to encompass several pin element rows. It can therefore be larger than one pin element spacing.

[0040] The seal device height specifies the distance from the base plane of the substrate holder to the seal device surface. It must be less than the pin element height to ensure protrusion of the additional pin element.

[0041] The seal fixture setback specifies the distance from the pin element surface to the seal fixture surface. It is the distance that a tool, preferably a cutting tool, in particular a milling cutter, removes relative to the pin element height to create the seal fixture height. The sum of the seal fixture height and the seal fixture setback is equal to the pin element height. This would make specifying either the seal fixture height or the seal fixture setback redundant. However, both are used: the former to obtain a quick estimate of the height and the latter to determine how much material a tool must remove to create the seal fixture surface.

[0042] The sealing device recess is less than 100 pm, preferably less than 10 pm, even more preferably less than 1 pm, most preferably less than 100 nm, most preferably less than 10 nm. The sealing device should therefore be located as close as possible to the substrate, but not touch it.

[0043] The most preferred embodiment provides that all pin elements, regardless of their position on the substrate holder, i.e., pin elements and other pin elements, have the same pin element height. This ensures that a substrate always rests at the same height across the entire surface.

[0044] It is also conceivable that the pin element height changes with the position of the pin element. For example, it would be conceivable that the elastic behavior of a pin element on a sealing device differs from the elastic behavior of a pin element outside of a sealing device due to the underlying sealing device. In this case, it might be appropriate to make the pin element on a sealing device slightly larger or slightly smaller than the other pin elements to account for the changed elastic behavior.

[0045] In the following, embodiments are described with the aid of which a correspondingly high pin element density can be achieved.

[0046] In a first exemplary embodiment of the present invention, the sealing devices are constructed to be located between the pin elements without removing a single pin element.

[0047] In a second exemplary embodiment of the present invention, the sealing devices are constructed such that pin elements are located thereon. The pin elements directly connected to the base plane are simply referred to as pin elements, and the pin elements located on the sealing devices are referred to as further pin elements or sealing device pin elements. The height of the pin elements is preferably identical to the sum of the height of the sealing device and the height of another pin element. In other words, the tips of the pin elements and the further pin elements are preferably located in the same plane. The further pin elements create a vacuum leak on the sealing devices.Preferably, the height of the additional pin elements must therefore be as low as possible and / or several sealing devices with additional pin elements must be created one after the other, so that a separation area is created that acts as a zone separator.

[0048] In a third exemplary embodiment of the present invention, all pin elements have the same height, but some pin elements are surrounded by a sealing device, i.e., they also end at the base plane of the substrate holder. Preferably, the pin elements in the sealing devices are created by circular material removal. The tools must operate with corresponding precision.

[0049] In a fourth exemplary embodiment of the present invention, the features of the second and third embodiments are combined. At least one sealing device of at least one separation region is wide enough to encompass at least two rows of pin elements. The pin elements of the rows of pin elements can then be produced according to the second embodiment, according to the third embodiment, or according to a combination of the embodiments.

[0050] The present invention further provides a method for producing a substrate holder according to the invention, preferably with a dissolution of material to form pin elements, sealing devices, and / or additional pin elements. All advantages and properties described for the substrate holder can be applied analogously to the method and vice versa.

[0051] The substrate holder preferably comprises a material of one of the following material classes

[0052] • Preferably made of ceramic, especially o SiC, SisN4

[0053] • Pure metal, especially o aluminum

[0054] • Pure metal alloy o Nickel-based alloy, copper-based alloy, aluminum-based alloy

[0055] • Metal-carbon alloy o steel, especially

[0056] ■ Free-cutting steel

[0057] ■ Tool steel

[0058] In the preferred monolithic design, the pin elements and sealing devices are then made of the same material, as they were made from the substrate holder.

[0059] The substrate holder is processed using at least one of the following manufacturing processes

[0060] • Machining, especially o milling

[0061] • Chemical processing, particularly in connection with o Lithography, particularly with

[0062] ■ Photolithography

[0063] ■ Imprint lithography

[0064] ■ DMD exposure o Development o Stripping o Masking o Etching

[0065] • ion beam processing • sandblasting with prior masking of the areas not to be sandblasted

[0066] • Laser processing

[0067] • Pour

[0068] • Presses

[0069] • Forging

[0070] • Hot stamping

[0071] • Imprinting with subsequent thermal or electromagnetic curing

[0072] • 3D printing

[0073] The machining process used preferably produces the pin elements and sealing devices from a semi-finished product by material removal, casting processes or plasticizing processes.

[0074] The following manufacturing processes remove material from a semi-finished product to create the substrate holder: all machining operations, in particular milling, all chemical machining operations, in particular etching processes, ion beam machining, sandblasting, laser machining.

[0075] The casting manufacturing process creates the substrate holder from a solidifying melt.

[0076] The manufacturing processes of pressing, forging and hot stamping plasticize a semi-finished product, preferably a circular disc, by the action of a die and / or a forging tool on the semi-finished product, in particular repeatedly or for a longer period of time.

[0077] In the imprinting manufacturing process, an embossing compound is embossed and then hardened thermally and / or by means of electromagnetic radiation.

[0078] In the 3D printing manufacturing process, the component is sintered and built up from a powder through selective curing by means of a laser. This process is often referred to as additive manufacturing. The present invention further relates to a method for holding a substrate with a substrate holder according to the invention, preferably during a machining operation. All advantages and properties described for the substrate holder can be applied analogously to the subject matter of the method, and vice versa.

[0079] Further advantages, features, and details of the invention will become apparent from the following description of preferred embodiments and from the drawings. These show:

[0080] Figure 1 a plan view and an enlargement of the prior art

[0081] Figure 2 a top view and an enlargement of a substrate holder

[0082] Figure 3 is a partial top and side view of a first embodiment

[0083] Figure 4 is a partial top and side view of a second embodiment

[0084] Figure 5 is a partial top and side view of the third embodiment

[0085] Figure 6 is a partial top and side view of the fourth embodiment and

[0086] Figure 7 shows a partial side view of an application.

[0087] In the figures, identical components or components with the same function are marked with the same reference numerals.

[0088] Figure 1 shows a schematic, not to scale, top and side view of a separation area 4 containing a single sealing device 5 PA This is an exemplary separation area 4, as is known from the prior art. For the production of the sealing devices 5 PAall pin elements 6 along the sealing devices 5 PA This breaks the homogeneity of the pin element surface density. The sealing devices 5 PA the same height as the pin elements 6 and therefore produces the negative effects mentioned above.

[0089] Figure 2 shows a schematic, not-to-scale, simplified plan view of a substrate holder 1, which comprises a plurality of zones 2, 2', in particular a first zone 2 and a further zone 2', which have fixing elements 3, in particular vacuum fixings. The zones 2, 2' are separated from one another by separating regions 4. A separating region 4 generally comprises at least one sealing device 5 (in Figure 2, a sealing device 5' according to Figure 4 is shown as an example, but alternative sealing devices 5', 5", 5'", as shown in Figures 3 or 5 to 7, are also conceivable). In special cases, the separating region 4 can also have only a single sealing device 5. The sealing devices 5 of the separating region 4 cannot be shown in the (non-enlarged) plan view for reasons of space.Therefore, enlargement B shows a schematic, not to scale, simplified, enlarged plan view of a separating region 4 which has three sealing devices 5' which separate a first zone 2 from a second zone 2'. In the embodiment shown, two rows of pin elements 6 are located between each individual sealing device 5'. Furthermore, it can be seen that further pin elements 6' are located in the region of the sealing devices 5', which are preferably formed on a side facing the substrate 7 during operation, i.e. protrude from the substrate holder or the sealing device 5'. The further pin elements 6' are thus integrated into the sealing device 5'. The separating region 4 created in this way is therefore not able to hermetically seal the two zones 2 from one another in a vacuum-tight manner when the substrate 7 (not shown) is lying on top.Due to the dimensions of the pin elements 6 and / or the additional pin elements 6' listed below and / or preferably the use of multiple sealing devices 5' per separation area 4, a sealing device labyrinth is created that at least complicates or slows down the passage of a fluid, in particular gas, between the two zones 2. The flow resistance is increased for this purpose. This allows adjacent zones 2 to be operated with different vacuum or pressure levels. On the other hand, the distance between the pin elements 6 and / or additional pin elements 6' can be further minimized. This design advantageously makes it possible to manufacture or place sealing devices 5' between the pin elements 6 and, in particular, to utilize the installation space as economically as possible.Figure 3 shows a schematic, not-to-scale top and side view of a separation area 4 comprising a sealing device 5 in a first exemplary embodiment of the present invention. The pin elements 6 are arranged in a hexagonal grid, which has the advantage that each pin element 6 has the same spacing p. p (English: pin pitch) to its nearest neighbors. This pin element arrangement achieves a particularly high level of homogeneity and isotropy. The sealing device 5 is manufactured between the pin elements 6 and, on the other hand, has a non-vanishing, but preferably very small, setback s r(English: seal recess). In contrast to the prior art, no pin elements 6 are removed, but the sealing devices 5 are placed between the pin elements 6. In the illustrated embodiment, the sealing device 5 is designed in a strip-shaped manner, wherein the strip-shaped sealing device 5 has a substantially straight course. However, wave-shaped or other courses for the sealing device 5 are also conceivable. For example, the sealing device 5 is slightly wavy and snakes around the pin elements 6, i.e., over short distances, it is not as straight as in Figure 3. However, such an additional illustration is omitted. Because no pin elements 6 have to be removed, the pin element surface density can remain constant across the separation area 4. In the specific case of Figure 3, the separation area 4 has only a single sealing device 5. A separation area is conceivable

[0090] 4 with several such sealing devices 5.

[0091] Figure 4 shows a schematic, not-to-scale top and side view of a separation area 4 comprising three sealing devices 5' in a second exemplary embodiment of the present invention. In this case, the pin elements 6, 6' are arranged along a square grid. The use of a different, in particular hexagonal, grid is also conceivable. This embodiment has pin elements 6 that are directly connected to the base plane of the substrate holder 1, as well as further pin elements 6' that are located on the sealing devices 5'. Due to this compact design, the distance p p (English: pin pitch) between the pin elements 6 and further pin elements 6' can be chosen even more closely, compared to solutions where only pin elements 6 are used between the sealing devices

[0092] 5 are provided, as is indicated by way of example in Figure 3. Preferably, the pin spacing between two pin elements 6 is the same as the spacing between a pin element 6 and a further pin element 6'. Pin elements 6 and further pin elements 6' are arranged equidistantly, in particular along a radial direction of the substrate holder starting from a center or along a planned bonding direction. This maintains the homogeneity of a pin element distribution of the pin elements 6, 6' across the sealing devices 5'. However, it is also conceivable that the pin spacing between two pin elements 6 differs from the pin spacing between a pin element 6 and a further pin element 6'. The pin elements 6 and further pin elements 6' have a pin element diameter pd (English: pitch diameter) and / or a cross-sectional area which is defined, for example, by a contact surface or bearing surface with which the pin element 6 or the further pin element 6' contacts the substrate 7, and / or which is dimensioned perpendicular to a direction of extension of the pin elements 6 or the further pin elements 6'. If the pin elements 6 and / or further pin elements 6' have a geometry deviating from a circular shape, the pin element diameter pd must be reinterpreted accordingly. If the geometry is a square, for example, the parameter pd represents a side length of the square or the length of its diagonal. The pin elements 6 have a pin element height ph (English: pitch height). The sealing device has a width s. w (seal width), a height Sh (seal height) and a recess, a depression or a recess s rThe height Sh can therefore also be interpreted as the height of the pin element 6' relative to the surface of the sealing device 5'. In particular, the embodiment shown in Figure 4 proves to be particularly advantageous because it is comparatively easy to manufacture.

[0093] Figure 5 shows a schematic, not-to-scale top and side view of a separation area 4 formed from three sealing devices 5" in a third exemplary embodiment of the present invention. The dimensions are omitted here. They can be found in the description of Figure 4. This embodiment has only pin elements 6, which are directly connected to the base plane of the substrate holder 1, as well as sealing devices 5". However, the additional pin elements 6 within the sealing devices 5" extend to the base plane of the substrate holder 1 and are completely surrounded by the sealing device 5". They are integrated into the sealing device 5". This embodiment has the advantage that the mechanical, in particular elastic, properties of all pin elements 6 are identical, since their geometric parameters match.A manufacturing tool required for this purpose must be capable of cutting areas out of the sealing devices 5". Figure 6 shows a schematic, not to scale top and side view of a separating area 4, which comprises three sealing devices 5", 5'", in a fourth exemplary embodiment of the present invention. It can be seen that the sealing device 5'" extends over three rows of pin elements and is designed such that the two outer rows of pin elements were manufactured according to the second embodiment (see Figure 4) and the middle row of pin elements were manufactured according to the third embodiment of the invention (see Figure 5). The fourth embodiment of the invention therefore represents a combination of two other embodiments. Furthermore, it is intended to show that a sealing device 5'" can extend over several rows of pin elements.Accordingly, the sealing device 5'" has a different sealing device width Sw'. It is not absolutely necessary for the second and third embodiments to be combined in the fourth embodiment. It is also conceivable for the sealing device width s. w ' comprises at least two rows of pin elements, the pin elements of which are constructed exclusively according to the second embodiment. Analogously, one can imagine a sealing device having a sealing device width s w ' comprises at least two rows of pin elements, the pin elements 6 or further pin elements 6' of which are constructed exclusively according to the third embodiment. The distinguishing feature would then be exclusively the sealing device width s w'. It should also be shown that different sealing devices, for example the sealing devices 5", 5'", can be combined within a separation area 4. For the sake of clarity, all possible combinations are not shown. Those skilled in the art know and understand how the embodiments and parameters can be combined to produce any desired sealing devices and separation areas.

[0094] All pin elements 6, 6' and sealing devices 5, 5', 5", 5'" shown in the figures are depicted as monolithic or integral, i.e., constructed from one and the same component. For the sake of completeness, it should be noted again that the sealing devices 5, 5', 5", 5'" and / or the pin elements 6, 6' could theoretically also be individual components inserted into the substrate holder 1. Such embodiments could be used with lower pin element and sealing device densities. Furthermore, by selecting individual sealing devices 5, 5', 5", 5'" and / or pin elements 6, 6', a material different from that of the substrate holder 1 could be used. Figure 7 shows a schematic, not to scale side view of a separation area 4 comprising three sealing devices 5", 5'", according to a fourth embodiment of the present invention (see Figure 6), on which a substrate 7 rests.On the left side of the side view is zone 2 with a pressure p1 generated by the vacuum fixation. On the right side of the side view is zone 2' with a pressure p2 generated by the vacuum fixation. The two pressures p1 and p2 do not necessarily have to be equal. However, the separation area 4 creates a labyrinth of sealing devices that greatly impedes fluid flow from one zone to the other. If the pumps for zones 2, 2' operate efficiently enough, the desired pressures p1 and p2 can be monitored, controlled, and regulated. Preferably, however, the substrate 7 never touches the sealing device surface of the sealing devices 5", 5'", and the pin element spacing of the pin elements 6, 6' can not only be designed to be minimal, but ideally also homogeneous.

[0095] List of reference symbols:

[0096] 1 substrate holder

[0097] 2, 2' Zone

[0098] 3 Fixing element

[0099] 4 Separation area

[0100] 5 PA , 5, 5', 5", 5'" sealing device

[0101] 6, 6' pin element, additional pin elements

[0102] 7 Substrate ph Pin element height pd Pin element diameter pp Pin element spacing sw, sw' Sealing device width sh Sealing device height sr Sealing device recess

Claims

Claims 1. Substrate holder (1) for holding a substrate (7) during a processing operation, for example during a bonding process, lithography process, coating process and / or cleaning process, wherein the substrate holder (1) has a separating region (4) for separating regions with different pressure levels which are established when holding the substrate (7) between the substrate holder (1) and the substrate (1), wherein the separating region (4) has at least -- a sealing device (5, 5', 5”, 5”') and -- a pin element (6) and / or a further pin element (6'), wherein -- the pin element (6') and / or the further pin element (6') and -- the sealing device (5, 5', 5", 5"') is designed such that, in order to form a contactless sealing region, the pin element (6) and / or the further pin element (6') at least partially prevents contact in the separating region (4) between the sealing device (5, 5', 5", 5"') and the substrate (1) when holding the substrate (1).

2. Substrate holder (1) according to claim 1, wherein the pin element (6) and / or the further pin element (6') protrudes relative to the sealing device (5, 5', 5", 5"').

3. Substrate holder (1) according to one of the preceding claims, wherein the further pin element (6') is integrated into the sealing device (5, 5', 5", 5"').

4. Substrate holder (1) according to claim 3, wherein for the integration of the further pin element (6') into the sealing device (5, 5', 5", 5"'), the further pin element (6') is arranged on the sealing device (5, 5', 5", 5"').

5. Substrate holder (1) according to claim 3 or 4, wherein for the integration of the further pin element (6') into the sealing device (5, 5', 5", 5"'), the further pin element (6') is surrounded by the sealing device (5, 5', 5", 5"') at least partially, preferably circumferentially and particularly preferably completely circumferentially, and preferably in a recess in the sealing device (5, 5', 5", 5"') is embedded.

6. Substrate holder (1) according to one of the preceding claims, wherein the substrate holder (1) has a first zone (2) and a second zone (2'), wherein the first zone (2) is separated from the second zone (2') by the separation region (4).

7. Substrate holder (1) according to claim 6, wherein the separating region (4) has a plurality of sealing devices (5, 5', 5", 5"'), in particular each with a further pin element (6'), wherein the sealing devices (5, 5', 5", 5"') are arranged one behind the other along a direction which runs from the first zone (2) to the second zone (2').

8. Substrate holder (1) according to one of the preceding claims, wherein the separating region (4) has a self-contained course, for example a frame-shaped course.

9. Substrate holder (1) according to one of the preceding claims, wherein a lateral extension of the sealing device (5, 5', 5", 5"') is greater than a lateral extension of the further pin element (6').

10. Substrate holder (1) according to one of the preceding claims, wherein - the pin element (6) and / or the further pin element (6') and the sealing device (5, 5', 5", 5"') or - preferably the substrate holder (1) is designed monolithically.

11. Substrate holder (1) according to one of the preceding claims, wherein a plurality of further pin elements (6') are integrated in a common sealing device (5, 5', 5", 5"').

12. Substrate holder (1) according to one of the preceding claims, wherein a pin element spacing between 0.1 mm and 10 mm, preferably between 0.2 mm and 5 mm, more preferably between 0.5 mm and 2.5 mm, most preferably between 1.0 mm and 2.0 mm, most preferably about 1.5 mm.

13. Substrate holder (1) according to one of the preceding claims, wherein respective pin spacings between adjacent pin elements (6) or further pin elements (6') on the one hand and further pin elements (6') or pin element (6) on the other hand are substantially constant along a predetermined direction.

14. Method for producing a substrate holder (1) according to one of the preceding claims, preferably with a dissolution of material for forming the pin element (6), the sealing device (5, 5', 5", 5"') and / or a further pin element (6').

15. Method for holding a substrate (7) with a substrate holder (1) according to one of claims 1 to 13, preferably as part of a machining operation.

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