Method and system for substrate etching and substrate holder

Abstract

The present invention relates to a method (100) and system (1) for substrate etching and a substrate holder (30). A substrate blank (2) is placed (S2) in the substrate holder (30), and the substrate blank surface (4) is treated (S3) with an etching medium (41). According to the present invention, prior to treatment with the etching medium (41), the substrate blank (2) is irradiated with a laser beam (3) along the outer contour (6) of a target substrate (5), whereby the target substrate (5) is separated from the substrate blank (2) during treatment with the etching medium (41).

Description

[Technical Field]

[0001] The present invention relates to a method and system for substrate etching and a substrate holder. [Background technology]

[0002] Etching processes are known for producing substrates with desired surface properties and / or for correcting the dimensions, especially the thickness, of substrates. Typically, a number of substrates, e.g. made of glass (SiO2), are fixed in a substrate holder (carrier) and then exposed to an acidic and / or alkaline etching medium.

[0003] A problem with such etching processes is the common occurrence of etch marks, also known as shadowing, which are formed by fixing the substrate in a substrate holder. To obtain a substrate without etch marks, complex post-processing steps such as trimming or polishing the etched substrate are required. Summary of the Invention

[0004] The object of the present invention is to improve the etching of substrates and in particular to enable the efficient production of substrates free from etching marks.

[0005] This object is achieved by a method and system for substrate etching and a substrate holder according to the independent claims.

[0006] Preferred embodiments of the invention are the subject of the dependent claims and the following description.

[0007] In a method for substrate etching according to a first aspect of the invention, a substrate blank is placed in a substrate holder and the substrate blank surface is treated with an etching medium. According to the invention, prior to treatment with the etching medium, the substrate blank is irradiated with a laser beam along the outer contour of the target substrate, so that the target substrate is separated from the substrate blank, particularly automatically, during treatment with the etching medium.

[0008] One aspect of the present invention is based on the approach of pretreating a substrate blank using a laser beam so that the etching effect of an etching medium on the substrate blank is enhanced or accelerated in one or more predetermined regions on the substrate blank surface. It is advantageous to irradiate the substrate blank so that a portion of the substrate blank corresponding to the target substrate is or can be etched during the etching process. Such etching-induced separation of the target substrate from the substrate blank allows the substrate blank to be fixed in a substrate holder without shadowing the target substrate. In other words, the substrate blank can be placed in a substrate holder so that the region of the substrate blank corresponding to the target substrate to be subsequently separated is not contacted by the substrate holder.

[0009] Preferably, the laser beam is applied to the substrate blank along the outer contour of the target substrate. For example, areas on the substrate blank surface that are on or together form the desired outer contour of the target substrate separately can be irradiated. It has been shown that the molecular bonds of the substrate material can be weakened or loosened using laser irradiation. This can make it easier for the etching medium to dissolve the substrate material or its components in these areas. The correct intensity of the substrate material, and thus the (local) etching effect of the etching medium, can be achieved with little effort by selecting appropriate laser parameters, such as, for example, wavelength, power or pulse energy, pulse duration, focus position, etc.

[0010] It is advantageous to place the substrate blank in the substrate holder so that the area enclosed by the outer contour is not contacted by the substrate holder. In this way, etching marks on the target substrate can be reliably and easily avoided.

[0011] Preferably, the substrate blank remains in the substrate holder until the target substrate is separated from the substrate blank. It is advantageous to terminate the etching process immediately after the target substrate is separated. This prevents the target substrate from being in prolonged contact with the substrate holder in the etching medium, which could result in etching marks on the target substrate.

[0012] In the following, preferred embodiments of the present invention and developments thereof are described, which may be combined with each other and with the aspects of the invention described below, unless expressly excluded.

[0013] In a preferred embodiment, the substrate blank is illuminated with a laser beam before being placed in the substrate holder, which may facilitate and / or increase the accuracy of the illumination of the substrate blank.

[0014] In a further preferred embodiment, the substrate blank is irradiated with a laser beam along the outer contour of the target substrate, such that through-holes are generated in the substrate blank along the outer contour of the target substrate when the substrate blank is treated with the etching medium. In other words, the substrate blank can be irradiated such that through-holes arranged along the outer contour and particularly aligned along the outer contour are formed in the substrate blank during etching. For this purpose, it is advantageous to irradiate the substrate blank with laser pulses. This is also advantageous because it makes it possible to achieve a particularly high energy input per unit time.

[0015] During the etching process, the through holes may continue to be formed. In particular, the through holes may grow, i.e., their diameter may increase. Expectedly, the etching process continues until adjacent through holes join together, i.e., the material layer between the two through holes is substantially completely etched away, thereby separating the target substrate from the substrate blank. The creation of through holes, in particular growing through holes, allows the target substrate to be separated particularly reliably and gently during etching.

[0016] In a further preferred embodiment, the substrate blank is irradiated with a laser beam along the outer contour of the target substrate such that through holes are generated in the substrate blank at a predetermined distance from one another along the outer contour of the target substrate when the substrate blank is treated with the etching medium. Expectedly, after a predetermined treatment time of the substrate blank with the etching medium, adjacent through holes connect with one another. By selecting the distance between adjacent impact points, in which area the laser beam strikes the substrate blank surface and through holes are generated during etching, the desired treatment duration can be particularly easily defined.

[0017] In a further preferred embodiment, the target substrate is separated from the substrate blank without etching marks, in particular substantially without etching marks. In particular, the substrate blank can be held, for example by means of a correspondingly designed substrate holder, and / or the substrate blank surface can be irradiated and / or treated with an etching medium, so that the target substrate is separated from the substrate blank without etching marks. This makes post-treatment aimed at removing such etching marks unnecessary.

[0018] In a preferred embodiment, the treatment duration is adapted to the speed of the etching process on the non-irradiated parts of the substrate blank surface. In particular, the treatment duration can be adapted to the desired intensity of the etching process on the non-irradiated parts of the substrate blank surface. This makes it possible to remove the target substrate from the substrate blank when the etching process on the non-irradiated substrate blank surface is also completed. In other words, therefore, the separation of the target substrate and the end of the "traditional" etching process can be substantially synchronized, for example, for surface correction.

[0019] In a further preferred embodiment, a substrate holder is placed in an etching medium bath to treat the substrate blank surface with the etching medium. The substrate holder is suitably removed from the etching medium bath immediately after the target substrate has been separated from the substrate blank. For example, the substrate holder can be removed from the etching medium bath immediately after a specified treatment time has been reached. This prevents the surface of the target substrate from being etched more than desired and / or prevents etching marks from forming on the separated target substrate, which may now come into contact with the substrate holder.

[0020] In a further preferred embodiment, the separated target substrate is captured using a substrate holder, which suitably comprises a capturing device for this purpose. For example, the substrate holder may have one or more capturing elements positioned adjacent to and / or below the substrate blank placed in the substrate holder. These capturing elements can be designed, for example, as pins. Thus, the target substrate can fall off the substrate blank after separation, and it is safely captured and guided by the capturing elements.

[0021] In a further preferred embodiment, the substrate blank is held in the substrate holder by a configuration such that the substrate blank surface is inclined relative to the vertical when the substrate holder is arranged horizontally. In other words, the substrate blank is held in the substrate holder at a predetermined angle so that the target substrate can fall off the substrate blank after removal. The above configuration of the substrate blank in the substrate holder can significantly facilitate the separation process. In particular, it can be ensured in this way that the separation is automatic and directed, which increases the efficiency of the process.

[0022] In a further preferred embodiment, the substrate blank surface, when aligned horizontally, is inclined with respect to the vertical by an angle of between 0° and 90°, preferably between 10° and 90°, due to the configuration of the substrate blank in the substrate holder. Tests have shown that this allows a particularly reliable separation of the target substrate from the substrate blank. In particular, an inclination of 10° or more can reliably avoid tilting of the target substrate in the remaining substrate blank, i.e., in the remaining "frame", or at least reduce the risk of such tilting.

[0023] In a further preferred embodiment, the laser beam is applied so that the target substrate separates from the substrate blank after a predetermined treatment time with the etching medium. It is advantageous to select a shorter treatment time or a treatment time that is substantially equal to the time required to achieve the desired etching effect on the substrate blank surface in the non-irradiated parts. This can ensure that the target substrate is separated from the substrate blank at the end of the desired etching process, for example for surface correction.

[0024] In a further preferred embodiment, the substrate blank is irradiated with the laser beam only on one side, which is approximately perpendicular to the surface of the substrate blank. The penetration depth of the laser beam into the substrate blank, and possibly also the resulting correction of the substrate material for the effects of the etching medium, can be set by selecting the laser parameters. Irradiating the substrate blank only on one side can speed up the process and / or reduce the laser irradiation effort.

[0025] In a further preferred embodiment, the substrate blank is irradiated with a laser beam on two opposing sides that are substantially perpendicular to the substrate blank surface. Here, too, the penetration depth of the laser beam can be set for each side independently of each other, as needed. Irradiation of the substrate blank on both sides allows targeted etching along the outer contour of both the front and back sides of the substrate blank, and consequently faster separation of the target substrate during treatment with the etching medium.

[0026] In a further preferred embodiment, the irradiation on the two opposite sides is carried out with different laser parameters. For example, the laser parameters can be selected so that the penetration depth of the laser beam on one side of the substrate blank is deeper than the penetration depth of the laser beam on the opposite side. This can be used to influence the processing time required to trigger the target substrate with the etching medium. In particular, this makes it possible to control the required processing time. For example, the required processing time can be reduced by performing the etching process on both sides of the substrate.

[0027] In a further preferred embodiment, when irradiating the substrate blank with a laser beam along the outer contour of the target substrate, the laser pulses strike the substrate blank surface at least partially within a region of equally spaced impact points, the distance of which can be selected depending on the material. The distance between adjacent impact points can be, for example, 1 μm to 15 μm, preferably 2 μm to 10 μm, in particular 3 μm to 5 μm. Ideally, the impact points lie at least partially on a straight line. This makes it possible to achieve uniform etching along the outer contour.

[0028] However, in principle, other, possibly irregular, configurations of the impact points are also conceivable, for example the impact points may extend partly along curves, the configuration of the impact points may depend inter alia on the substrate material and / or geometry requirements.

[0029] In a further preferred embodiment, when the substrate blank is irradiated with a laser beam along the outer contour of the target substrate, the laser pulses preferably strike the substrate blank surface in a region of impact points that are at least partially equally spaced. Conveniently, the impact points are at least partially located on two or more lines extending parallel to one another. By irradiating the substrate blank in this manner, the substrate material can be compensated for with respect to the effect of the etching medium on a larger area around the area corresponding to the target substrate. Therefore, in particular, the effect of the etching medium can be enhanced or accelerated along a wide "band" around the target substrate. During the etching process, this can create a wider gap between the target substrate and the remaining substrate blank. This is particularly advantageous for thick substrate blanks, since it can prevent the target substrate from tilting during separation, or at least reduce the risk of tilting. Furthermore, the processing time required to completely release the target substrate is also affected in this way.

[0030] In a further preferred embodiment, the substrate surface is treated with an etching medium containing an alkaline compound, such as potassium hydroxide (KOH), tetramethylammonium hydroxide (TMAH), sodium hydroxide (NaOH) and / or lithium hydroxide (LiOH). This allows the target substrate to be particularly reliably separated. In particular, such an etching medium allows for particularly controlled etching and, as a result, controlled separation of the target substrate.

[0031] In a further preferred embodiment, the substrate blank surface is treated with the etching medium at a temperature of 90°C or higher, preferably 110°C or higher, in particular 120°C or higher. Particularly preferably, the substrate blank surface is treated with the etching medium at about 120°C. For this purpose, for example, an etching medium bath may be brought to the above temperature, and the substrate blank may be immersed in the etching medium bath. At the above temperature, the etching medium can act reliably and in a controlled manner on the irradiated areas on the substrate blank surface. By selecting a high temperature for the etching medium, such as 110°C or even 120°C, the etching process can be accelerated if necessary, especially compared to conventional etching processes.

[0032] It may be advantageous to treat the substrate blank surface with the etching medium at temperatures between 90°C and 190°C, preferably between 110°C and 170°C, in particular between 120°C and 150°C. Working within these temperature ranges makes it possible to avoid excessive evaporation of the etching medium. Moreover, excessive heating of the etching medium would consume a disproportionately large amount of energy with respect to improving the etching effect.

[0033] The temperature range selected can be application or substrate specific: conventional display glasses, for example, can be etched well at around 120° C., while certain ceramic glasses, which have a slower etching process, may require correspondingly higher temperatures.

[0034] According to a second aspect of the present invention, a system for substrate etching, in particular for carrying out the method according to the first aspect of the present invention, comprises a laser device configured to irradiate a substrate blank with a laser beam along the outer contour of the target substrate so that the target substrate is separated from the substrate blank, in particular automatically, during treatment with the etching medium. The system further optionally comprises a substrate holder on which the substrate blank can be placed, and an etching device configured to treat the irradiated substrate blank placed in the substrate holder with the etching medium. Such a system can be used, for example, to produce substrates without etching marks and with desired surface properties obtained by etching.

[0035] The laser device may comprise, for example, one or more solid-state lasers, such as fiber lasers. Conveniently, the laser device is configured to repeatedly generate one or more synchronously generated laser pulses. Preferably, the laser device is also configured to vary the position of the area where the one or more synchronously generated laser pulses impinge on the substrate blank surface, thereby allowing the outer contour of the target substrate to be "scanned." To this end, for example, at least a portion of the optics of the laser device may be mounted so as to be displaceable relative to the target substrate, or may be configured to influence the propagation direction of the laser beam.

[0036] The etching apparatus suitably comprises an etching medium reservoir within which the substrate holder and substrate blank can be placed.

[0037] According to a third aspect of the invention, in particular for use in the method according to the first aspect of the invention, a substrate holder for holding a substrate blank comprises a capture device configured to capture a target substrate that has been separated from the substrate blank during treatment of the held substrate blank with an etching medium, such that the separated target substrate can be safely and reliably removed from the etching medium bath and post-processed, e.g. cleaned and / or rinsed and dried.

[0038] The present invention will now be described in more detail with the aid of the drawings. Elements having the same effect are appropriately designated by the same reference numerals. The present invention is not limited to the embodiments shown in the drawings, even in terms of functional features. The foregoing description and the following description of the drawings include numerous features, some of which are summarized in the dependent claims. However, a person skilled in the art will be able to consider these features and all other features individually disclosed above and in the following description of the drawings, and combine them to form other useful combinations. In particular, all of the above features may be combined individually and in any suitable combination with the method according to the first aspect of the invention, the system according to the second aspect of the invention, and the substrate holder according to the third aspect of the invention.

[0039] The drawings show, at least partly diagrammatically: [Brief explanation of the drawings]

[0040] [Figure 1] An example of a method for etching a substrate using a corresponding system is shown. [Figure 2] 1 shows a plan view of an example substrate blank illuminated by a laser beam. [Figure 3] 3 shows in cross section an example of the substrate blank of FIG. 2 irradiated by a laser beam. [Figure 4] 1 shows an example of an etching treatment of a substrate blank with an etching medium. [Figure 5] 1 shows an example of a substrate holder. DETAILED DESCRIPTION OF THE INVENTION

[0041] 1 shows an example of a system 1 for performing a substrate etching method 100. The system 1 includes a laser device 20, a substrate holder 30, an etcher 40, and optionally a post-processing device 50.

[0042] In a method 100 that can be performed by this system 1, a substrate blank 2, such as a glass plate, is irradiated with a laser beam 3 in method step S1. A laser device 20 is suitably used for this purpose. The laser device 20 may comprise any suitable laser, for example a fiber laser, that generates the laser beam 3. The laser beam 3 preferably comprises a plurality of laser pulses that successively impinge on the substrate blank surface 4.

[0043] The substrate blank 2 is irradiated with a laser beam 3, in particular laser pulses, along the outer contour of the target substrate 5 (see FIG. 2). Advantageously, the outer contour is continuously "scanned" with the laser beam 3, in particular laser pulses. In other words, for example, the laser beam 3 preferably strikes the substrate blank surface 4 in a region of equally spaced impact points (see FIG. 4), the positions of which correspond to the outer contour. The regions in which the laser beam 3 strikes the substrate surface 4 can thus separately map the outer contour.

[0044] It is advantageous to irradiate the substrate blank 2 with the laser beam 3 in such a way that the target substrate 5 is separated from the substrate blank 2 during treatment with the etching medium 41. For this purpose, it may be necessary to adapt the laser parameters to the properties of the substrate blank 2, for example by configuring the laser device 20. It is conceivable, for example, to adapt the laser parameters to the material and / or thickness of the substrate blank 2. Such laser parameters may, for example, relate to the power, in particular the energy per laser pulse, the pulse time width, the distance between the impact points, the wavelength, etc.

[0045] By irradiating the substrate blank 2, the substrate material can thereby be corrected along its outer contour, in particular in the region of the impact point of the laser beam 3, so that the effect of the etching medium 41 is enhanced and / or accelerated. For example, in the case of a substrate made of quartz glass (SiO2), when irradiated with a suitable frequency, the atomic bonds between silicon atoms (Si) and oxygen atoms (O) can be at least partially broken and / or weakened, so that the material in this region can be dissolved very quickly by a subsequent wet chemical etching process. In particular, the irradiation can promote the following reaction processes: SiO2+2NaOH → Na2SiO3+H2O SiO2+6HF → H2SiF6+H2O

[0046] In a further method step S2, the substrate blank 2 is placed in the substrate holder 30. For example, the substrate blank 2 can be inserted into the substrate holder 30. For this purpose, the substrate holder 30 can have a holding device, for example in the form of a slot (see FIG. 5).

[0047] 1, the substrate blank 2 is preferably held in a configuration within the substrate holder 30 such that the substrate blank surface 4 is inclined relative to the vertical when the substrate holder 30 is aligned horizontally. This may facilitate separation of the target substrate 5 from the substrate blank 2 in a further method step S3.

[0048] In this method step S3, the substrate blank surface 4 is treated with an etching medium 41, preferably using an etching device 40. The etching device 40 may for this purpose have an etching medium bath consisting of the etching medium 41. Preferably, the substrate holder 30 together with the substrate blank 2 is immersed in the etching medium bath.

[0049] The etching medium 41 can be an alkaline or acidic liquid, for example, potassium hydroxide (KOH), sodium hydroxide (NaOH) or hydrofluoric acid (HF) can be used to treat the glass substrate.

[0050] The substrate blank 2 preferably remains in the etching medium 41 for at least a predetermined treatment time. After this treatment time has elapsed, the etching medium 41 advantageously melts the substrate material along its outer contour, particularly in the region of the impact point of the laser beam 3, to such an extent that a gap is formed between the target substrate 5 and the remaining substrate blank 2, the so-called "frame", which allows the target substrate 5 to be separated from the substrate blank 2.

[0051] Preferably, the detached target substrate 5 is captured in a further optional method step S4 by the substrate holder 30. To this end, the substrate holder 30 may comprise a capturing device (see FIG. 5).

[0052] In a further optional method step S5, the substrate holder 30 can be removed from the etching medium 41 together with the remaining substrate blank 2 and the separated target substrate 5. Conveniently, the target substrate 5 is then cleaned, for example by rinsing with a rinsing medium. The target substrate 5 can then be dried.

[0053] The cleaning and / or drying can be performed using a post-processing device 50. To this end, the post-processing device 50 suitably comprises a cleaning and drying chamber capable of accommodating the substrate holder 30.

[0054] FIG. 2 shows a first example of a substrate blank 2 illuminated with a laser beam in plan view, with the substrate blank surface 4 visible.

[0055] The substrate blank 2 was irradiated with a laser beam along the outer contour 6 of the target substrate 5 such that the target substrate 5 is separable from the substrate blank 2 when treated with an etching medium. The outer contour 6 is shown shaded.

[0056] During irradiation, the laser beam preferably strikes the substrate blank surface 4 in the region of impact points (see FIG. 4), which are preferably arranged consecutively in a line corresponding at least partially to the outer contour 6. When the laser beam strikes the substrate blank surface 4 and thereby corrects the substrate material, the etching effect of the etching medium is accordingly enhanced or accelerated.

[0057] In the illustrated example, the impact points are located on three different lines 7a, 7b, 7c that run partially parallel to one another. For convenience, all impact points on the same line 7a, 7b, 7c are equally spaced. The lines 7a, 7b, 7c are shown as dots, and each dot can be understood as an impact point.

[0058] As shown in FIG. 2, the lines 7a, 7b, and 7c are preferably nested, i.e., arranged one inside the other. In other words, an outer line 7a and an inner line 7c may be provided. The inner line 7c bounds the (future) target substrate 5, while the position of the outer line 7a relative to it determines the width of the gap created between the target substrate 5 and the remaining substrate blank 2 during the etching process. Depending on the desired width of the gap, the laser beam may strike the substrate blank surface 4 between the outer line 7a and the inner line 7c, as in this example, to ensure a uniform gap formation. The corresponding impact point may be located on line 7b, as in this example, or on several other lines. However, in principle, it is also possible to irradiate the substrate blank 2 so that the laser beam strikes the substrate blank surface 4 only in the region of impact points located only on two different lines 7a and 7c or only on one line 7a.

[0059] Figure 3 shows a cross section of the example substrate blank 2 of Figure 2 irradiated with a laser beam, where various irradiation options are shown purely for illustrative purposes.

[0060] On the one hand, the substrate blank 2 can be irradiated with the laser beam on only one side, which is indicated by the dashed lines, which indicate the penetration depth of the laser beam in the area of the impact points lying on the inner line 7c that bounds the target substrate 5.

[0061] The term "penetration depth" here refers in particular to the depth or depth range in which the laser beam interacts particularly strongly with the substrate material. In other words, "penetration depth" expediently refers to the depth or depth range in which the substrate material is modified in such a way that the etching effect of the etching medium is enhanced or accelerated.

[0062] The penetration depth can be adjusted by selecting appropriate laser parameters, such as wavelength, power or pulse energy, pulse duration, etc., in particular by adjusting the focal position or focal depth relative to the substrate blank surface 4 .

[0063] On the one hand, the substrate blank 2 can be irradiated on two opposite sides, i.e. on both the front and rear sides. Such two-sided irradiation is indicated by dashed lines, which indicate the penetration depth of the laser beam in the area of the impact points lying on the central line 7b or on the outer lines 7a, on the one hand, and on the corresponding opposite lines 7b', 7a', on the other hand.

[0064] Irradiation on two sides generally allows for symmetric irradiation (see lines 7b, 7b'). However, asymmetric irradiation is also possible (see lines 7a, 7a'). Such asymmetric irradiation can result in a greater penetration depth of the laser beam on one side than on the other, opposite side.

[0065] As shown in Figure 3, various illumination options can be used in conjunction, however it is also conceivable to illuminate exclusively in one or two planes, and in the case of two planes, exclusively symmetrically or asymmetrically.

[0066] By irradiating along two or more lines 7a, 7b, 7c that run at least partially parallel, the processing time required to release the target substrate can be influenced in particular. In principle, at least up to a certain limit, a faster separation of the target substrate from the substrate blank can be achieved by increasing the number of lines, i.e., by a wider gap. Alternatively or additionally, the processing time can also be influenced by the selected penetration depth of the laser beam.

[0067] 4 shows an example of an etching process of a substrate blank with an etching medium. The substrate blank is irradiated with a laser beam before the etching process. As a result, the substrate material in the shaded area 8, where the laser beam strikes the substrate blank surface 4, is appropriately corrected so that the etching effect of the etching medium is enhanced or accelerated. During the etching process, the substrate material is dissolved to a correspondingly greater extent in area 8. In this way, through holes 9 can be formed in the substrate blank in area 8.

[0068] As the etching medium treatment of the substrate blank progresses, the through holes 9 grow in size. In other words, the through holes 9 may gradually expand. This is shown by the dotted circles in FIG. 4. Depending on the distance between adjacent impact points, in which area 8 the laser beam strikes the substrate blank surface 4, adjacent through holes 9 will sooner or later join together. In other words, as the etching process progresses, the material layers between adjacent through holes 9 are substantially completely dissolved.

[0069] This mechanism advantageously results in the formation of a gap between the remaining substrate blank and the target substrate whose outer contour corresponds to the arrangement of impact points, thus allowing the target substrate to be separated from the substrate blank.

[0070] In the example shown in Figure 4, the impact points are regularly arranged on the substrate blank surface 4. In particular, the impact points are here located on dashed lines 7 and have a predetermined distance from each adjacent impact point. The areas 8 around the impact points where the laser beam strikes the substrate blank surface 4 are correspondingly regularly arranged and the through holes 9 are also correspondingly regularly formed.

[0071] The process duration required for connecting the through holes 9 and the associated separation of the target substrate can be specified, in particular, by selecting the distance between adjacent impact points or areas 8. In this regard, the process duration can be adjusted to the desired effect of the etching medium on the unirradiated, i.e. uncorrected, parts of the substrate blank surface 4. In other words, the process duration can be adjusted by specifying the distance between adjacent impact points or areas 8 such that the target substrate is dissolved into the uncorrected parts of the substrate blank at substantially the same time as the desired etching effect is achieved.

[0072] 5 shows a side view of an example of a substrate holder 30. The substrate holder 30 has a holding device 31 for holding a substrate blank 2 and a capturing device 32 for capturing a target substrate 5 that has been separated from the substrate blank 2 during treatment with the etching medium. For clarity, only one substrate blank 2 and one target substrate 5 are shown.

[0073] The holding device 31 is preferably designed so that the held substrate blank 2 does not come into contact in the area corresponding to the target substrate 5 to be separated. For this purpose, the holding device 31 suitably has a number of slots 33 into which the substrate blank 2 can be inserted. As a result, the contact of the substrate holder 30 with the substrate blank 2 can be limited to a long, narrow strip at the edge of the substrate blank 2. For example, the substrate blank 2 can be inserted into the slots such that the contact of the substrate holder 30 with the substrate blank 2 is limited to a portion that lies outside the area corresponding to the target substrate 5 to be separated. The area corresponding to the target substrate 5 to be separated remains unaffected (see FIG. 2 ). For clarity, in this case, only some of the slots 33 are labeled.

[0074] The slots 33 are suitably provided in at least one, in this example two, cross members 34 arranged between two side walls 36 of the substrate holder 30. In the case of more than two cross members 34, two of the slots 33 in different cross members 34 are aligned with respect to each other, so that only one substrate blank 2 can be placed in these two slots 33.

[0075] The holding device 31 is suitably designed to hold the substrate blank 2 such that the substrate blank face 4 is inclined relative to the vertical when the substrate holder 30 is aligned horizontally. For this purpose, the slots 33 may be provided at a corresponding angle in the cross member 34. Preferably, the slots 33 are arranged such that an inclination of the substrate blank face 4 relative to the vertical of more than 0°, preferably 10° or more, but at most 90°, is achieved.

[0076] The substrate holder 30 also has a bridge 35 on which the substrate blank 2, which is held in particular in the slot 33 of the holding device 31, can rest at its lower end. The bridge 35 is also connected to the side wall 36. Preferably, the bridge 35 also has a slot 33, as shown in Figure 5, so that the end of the substrate blank 2 can also be fixed when placed in the slot 33 of the cross member 34.

[0077] If desired, multiple bridges 35 and cross members 34 may be arranged behind each other, i.e., perpendicular to the plane of the drawing, to increase the capacity of the substrate holder 30.

[0078] The capture device 32 preferably has a large number of capture elements 37, only some of which are numbered for clarity. In this example, the capture elements 37 are designed as pins that protrude horizontally from at least one, in this case both, cross members 34. The capture elements 37 are suitably arranged adjacent to the slots 33. One capture element 37 may be provided for each slot 33 and cross member 34. In other words, one capture element 37 may be assigned to each slot 33 in the cross member 34. In principle, however, multiple capture elements 37 per slot 33 are also conceivable.

[0079] After separation from the substrate blank 2 , the target substrate 5 can consequently fall off at one lower end onto the bridge 35 , with it being held laterally by the capture element 37 .

[0080] For convenience, the bridge 35 has a number of recesses 38, each of which is designed to fix a detached target substrate 5. Fixing here refers in particular to the stabilization of the position of the detached target substrate 5 in the horizontal plane. In other words, fixation can prevent or at least inhibit movement along the bridge 35, in particular of the edge of the target substrate 5 facing the bridge 35.

[0081] The recesses 38 may be designed and particularly arranged so that the target substrate 5, having been removed from the substrate blank 2, may particularly automatically slide into one of the recesses 38. For this purpose, each recess 38 may be provided adjacent to a slot 33 in the bridge 35. [Explanation of symbols]

[0082] 1 System 2 PCB blanks 3. Laser beam 4 Blank side of board 5 Target board 6 Outer contour 7 Lines 7a Outside Line 7a´ Outside line 7b Central Line 7b´ Center line 7c Inside line 8 areas 9 Through holes 20 Laser Device 30 Substrate holder 31 Holding Device 32 Capture Device 33 slots 34 Cross member 35 Bridge 36 side wall 37 Capture Elements 38 Recess 40 Etching equipment 41 Etching medium 50 Aftertreatment device 100 ways S1~S5 method steps

Claims

1. A method (100) for etching a substrate, wherein a substrate blank (2) is placed in a substrate holder (30) (S2), and the substrate blank surface (4) is treated with an etching medium (41) (S3), Prior to processing with the etching medium (41), the substrate blank (2) is irradiated with a laser beam (3) along the outer contour (6) of the target substrate (5) (S1), thereby separating the target substrate (5) from the substrate blank (2) during processing with the etching medium (41). The separated target substrate (5) is captured using the substrate holder (30) (S4), method (100).

2. The method according to claim 1 (100), wherein a substrate holder (30) for processing the substrate blank surface (4) with the etching medium (41) is introduced into an etching medium tank, and the substrate holder (30) is removed from the etching medium tank immediately after the target substrate (5) is separated from the substrate blank (2).

3. The method according to claim 1 (100), wherein the substrate blank (2) is held by a configuration within the substrate holder (30) such that the substrate blank surface (4) is inclined with respect to the vertical when the substrate holder (30) is aligned horizontally.

4. The method according to claim 3 (100), wherein the substrate blank surface (4) is inclined at an angle of 0° to 90°, preferably 10° or more, with respect to the vertical.

5. The method according to claim 1 (100), wherein the substrate blank (2) is irradiated with a laser beam (3) along the outer contour (6) of the target substrate (5), and at least partially the laser pulses strike the substrate blank surface (4) within a region (8) of equally spaced impact points, and the impact points lie on lines (7; 7a, 7b, 7c).

6. The method according to claim 1 (100), wherein the substrate blank (2) is irradiated with a laser beam (3) along the outer contour (6) of the target substrate (5), and within the region of the impact point, the laser pulse strikes the substrate blank surface (4), and the impact point is at least partially located on two or more lines (7a, 7b, 7c) that extend parallel to each other.

7. The method according to claim 1 (100), wherein the substrate blank (2) is irradiated with a laser beam (3) along the outer contour (6) of the target substrate (5), and within the region of the impact point, the laser pulse strikes the substrate blank surface (4), and the impact point is at least partially located on two or more nested lines (7a, 7b, 7c) and the inner line (7c) that borders the target substrate (5).

8. A substrate holder (30) for holding a substrate blank (2) for use in the method (100) according to any one of claims 1 to 7, the substrate holder (30) having a capture device (32) configured to capture a target substrate (5) separated from the substrate blank (2) during processing of the held substrate blank (2) by an etching medium (41).

9. A substrate holder (30) according to claim 8, having a holding device (31) for holding a substrate blank (2), wherein the holding device (31) has a plurality of slots (33) for inserting the substrate blank (2) such that contact between the substrate blank (2) and the substrate holder (30) is limited to portions located outside the region corresponding to the target substrate (5) to be separated.

10. The substrate holder (30) according to claim 8, wherein the capture device (32) comprises a plurality of capture elements (37) formed as pins.

11. The substrate holder (30) according to claim 9, wherein the capture device (32) comprises a plurality of capture elements (37) formed as pins, the capture elements (37) are arranged adjacent to the slots (33), and at least one capture element (37) is coupled to each slot (33) in order to capture the target substrate (5) separated from the substrate blank (2) held in each of the slots (33).

12. A substrate holder (30) according to claim 8, having two side walls (36) and a bridge (35) between the two side walls (36), wherein the lower end of the substrate blank (2) can be placed on the bridge (35) and / or a separated target substrate (5) can be dropped onto the bridge (35) at its lower end.

13. The substrate holder (30) according to claim 12, wherein the bridge (35) comprises a plurality of recesses (38), each of which is formed to stabilize a separated target substrate (5).

14. The substrate holder (30) according to claim 13, wherein the recess (38) is formed such that a target substrate (5) separated from the substrate blank (2) automatically slides into one of the recesses (38) at its lower end.

15. A system (1) for substrate etching, particularly for carrying out the method (100) according to any one of claims 1 to 7, A laser apparatus (20) configured to irradiate the substrate blank (2) with a laser beam (3) along the outer contour (6) of the target substrate (5) so that the target substrate (5) is separated from the substrate blank (2) during processing with an etching medium (41), A substrate holder (30) according to claim 8, wherein the substrate holder (30) is capable of arranging the substrate blank (2), An etching apparatus (40) configured to process a substrate blank (2) to be irradiated, placed in the substrate holder (30), with the etching medium (41), A system (1) equipped with the following features.

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