Method for removing areas of a layer applied to a substrate

Abstract

The invention relates to a method for removing at least one region (1) of a layer (3) applied to a substrate (2), wherein a respective region (1) to be removed is processed in such a way that at least one linear recess (5) is introduced into the layer (3) at least in sections along an outer contour (4) of the region (1), by ablating the layer (3) using a laser beam and thereby at least thermally separating the region (1) from adjacent areas of the layer (3). Energy is then introduced into the region (1) by means of the laser beam until a reduction in adhesion and / or a detachment of the layer (3) in the region (1) is achieved.Adjacent regions (1), between the successive processing of which a relative movement of the laser cutting tool and the substrate (2) occurs, are additionally processed in such a way that a tolerance compensation zone (6) is formed between these adjacent regions (1). The layer (3) is additionally processed in the tolerance compensation zone (6) for removal in such a way that at least one linear recess (5) is introduced into the layer (3) at each of its two desired ends (9) lying in a main extension direction (8), which runs transversely to the main extension direction (8) of the tolerance compensation zone (6).

Description

The invention relates to a method for removing at least a portion of a layer deposited on a substrate. In this case, a respective region to be removed is processed in such a way that at least one linear cutout is introduced into the layer at least in sections along an outer contour of the region by removing the layer by means of a laser beam and the region is thereby at least thermally separated from adjacent areas of the layer. Energy is then introduced into the region by means of the laser beam until a reduction in the adhesion and / or detachment of the layer in the region is achieved. In this case, adjacent regions, between the successive processing of which a relative movement of the one laser cutting tool and the substrate takes place, are processed in such a way that a tolerance compensation zone is formed between these adjacent regions.A large number of methods for producing structured and in particular conductive layers on a substrate, for example a printed circuit board, are known from the prior art. Etching and milling processes are considered to be the most widespread in this connection. However, both methods have distinct disadvantages, especially also for the field of prototype construction.Milling processes are time consuming and costly, particularly due to limited dynamics of milling machines used, as compared to other methods. These challenges are exacerbated in complex or densely packed patterning patterns. In addition, milling often results in the substrate underlying the layer to be patterned being subject to damage since it is typically ablated to achieve the necessary separation and / or isolation of structures on the substrate. Depending on the substrate, for example a printed circuit board made of a composite material of class FR4, this additionally results in particles which not only can impair the service life of the milling tools used, but also have to be classified as hazardous to health. Therefore, effective suction is required.Although etching processes generally have shorter fabrication times, these advantages are particularly relative in the field of prototyping. In addition, etching processes can be associated with disadvantages such as lack of structural accuracy and possible inaccuracies in the etchings. Etching can present difficulties in achieving high precision with very fine structures. The accuracy of the resulting patterning is limited due to, for example, undercutting, especially when complex fine detail designs are required. In addition, inhomogeneities in the etching solution can lead to uneven etching, for example, in particular in the case of large-area substrates. This, in turn, may result in undesirable variations in the structure dimensions. Above all, however, the performance of etching processes is associated with a high environmental impact, since aggressive etching solutions are frequently used. The etching products formed from the etching solutions and the removed materials are also usually highly environmentally harmful. Proper handling of these chemicals and their proper disposal are necessary to minimize environmental effects, which causes high costs.Thus, in particular for prototype construction and small-volume production, the use of laser systems for structuring layers on a substrate has become established. With such laser systems, detailed structures can be introduced into layers by a laser precisely detaching or cutting the layer material. This allows, among other things, the rapid prototype development and the production of small quantities without the need for expensive tool changes, as may be required in conventional production methods. The use of particularly environmentally damaging methods can also be dispensed with in this way. The use of laser systems enables high precision and flexibility, but exhibits weaknesses in the case of large-area material removal. The small beam diameter leads to longer processing times despite galvanometer scanners. If the substrate also has a comparable or even lower ablation threshold than the layer to be ablated, there is the risk of impermissible damage. The low ablation threshold of the substrate limits the possible energy input, whereby the conductive layer does not completely evaporate during large-area material removal, but rather is melted and displaced, which leads to material accumulations. Here, the laser energy is then no longer sufficient to reliably remove the conductive layer. An increase in the laser energy is in turn excluded in order to prevent damage to the substrate.In order to solve this problem, DE 10 2004 006 414 A1 describes a method for detaching a region of a conductive layer from a substrate. In this case, the region is first thermally insulated by the introduction of a linear cutout along its circumference. This step is carried out by means of a laser beam. Subsequently, the region to be removed is heated by the laser beam until the adhesion of the conductive layer to the substrate in this region is substantially reduced, whereby the region can be released from the substrate. The detachment then takes place under low adhesion forces, influenced by the force of gravity or external forces, as a result of which the substrate is not subjected to any further laser action. Preferably, the detachment of the region takes place by a targeted supply of compressed air, which enables the conductive layer to be raised from the edge to the center of the surface. Alternatively, the area to be released may be first divided into partial areas, instead of removing it as a whole.DE 10 2010 019 406 A1 represents a further development of the method explained above. In this case, the regions of a conductive layer to be removed are always divided into strip-shaped partial regions. The alignment of the thermally insulating recesses is selected such that these and thus also the insulated partial regions never run parallel to the main axes of the structures to be formed in the layer. Instead, they always meet the structures at an acute angle. This prevents a parallel thermal energy input, which significantly reduces undesired energy effects on the structures. This minimizes or even excludes the probability of damage to the structures.Furthermore, it is known that laser systems can regularly only process a section of a substrate via their galvanometer scanners, since these only cover a limited scanning field and, for complete processing, a relative movement between the processed laser tool and the substrate must therefore be provided via a traversing unit in order to row a plurality of scanning fields. Adjacent scan fields must be connected to one another as seamlessly as possible, which presents a challenge, in particular with small structural dimensions. Otherwise, discontinuities arise between the scan fields, which result in gaps or overlaps of the structures to be connected. In this case, particularly overlappings again involve the risk of impermissible damage to the substrate on account of an excessively high energy input. A precise connection between the scanning fields requires complex calibrations of the displacement unit while maintaining extremely tight tolerances.Approaches from the prior art are already known for addressing these problems. DE 10 2010 019 407 A9, for example, describes a method for introducing recesses into an electrically conductive layer formed on a substrate, as occurs, for example, in printed circuit boards. These recesses serve to electrically isolate structures such as conductor tracks and are introduced into the layer by a laser beam. The specific problem that arises here is that the ends of a single recess or of two different recesses do not meet seamlessly when introduced by a laser beam. In order nevertheless to achieve effective insulation via at least one recess, it is proposed to let the end sections of the recess run out parallel and specifically offset with respect to one another. In the case of a sufficiently small offset between the two end sections, the introduction of the recess into the layer alone brings about a high thermal energy input into the zone between the end sections. This leads to a reduction in the adhesion of the layer in this zone and also enables an automatic, undefined detachment of the layer between the end sections. It is also conceivable that the detachment is promoted after the adhesion is reduced. The method is thus disadvantageously suitable only for compensating small deviations. The undefined detachment also means a lack of control over the detachment process. Without clear definition and control of the detachment behavior, there is the risk of unpredictable results and thus undesired damage.DE 10 2008 014 263 A1 also discloses a method and a device for forming separating lines of a photovoltaic module having cells connected in series. To form the separating lines which are produced in the functional layers deposited on a transparent substrate, laser scanners are used whose laser beam generates a plurality of separating line sections arranged next to one another in the functional layer in the field scanned by it. The laser scanners are then moved relative to the coated substrate in the direction of the parting lines by a distance which corresponds at most to the length of the scanned field in order to form parting lines continuous through aligned parting line sections.Against this background, the object of the invention is to configure a method of the type mentioned at the beginning in such a way that reliable removal of regions of the layer is made possible with tolerances which are the same or higher than in the prior art and thus simplified calibration, and impermissible damage is avoided.This object is achieved according to the invention by a method according to the features of claim 1. The further embodiment of the invention can be taken from the dependent claims.According to the invention, a method is therefore provided for removing at least one region of an in particular electrically conductive layer applied - initially over the entire surface - on a substrate. The layer laminated on, for example, is preferably formed as a copper layer. The substrate itself may be made of, for example, a printed circuit board material such as a FR4 class composite material. Accordingly, in one embodiment, the substrate and layer would be configured as a copper-laminated printed circuit board or a printed circuit board blank. In a variant configuration, however, the substrate can also be a film, for example a polyimide film. Furthermore, an embodiment of the substrate made of glass is also conceivable.By removing at least two or more regions, a structure having a defined, preferably predetermined course is formed in the layer. This structure has characteristic major axes which are at right angles to each other. The structure can comprise, for example, at least one conductor track or a group of conductor tracks of a printed circuit board layout.Furthermore, it is provided according to the invention that a respective region of the layer to be removed is processed in such a way that at least one linear recess and / or interruption is introduced into the layer at least along a section or at least in sections along an outer contour of the region. Preferably, however, the introduction of the at least one, preferably exclusively one, recess takes place along the entire outer contour of the region.In a manner according to the invention, the introduction of the at least one recess is carried out by removing the layer by means of a laser beam, whereby the region is separated at least thermally, but preferably integrally, completely from adjacent areas of the layer. Energy is then introduced into the region by means of the laser beam until a reduction in the adhesion and / or detachment of the layer in the region is achieved. For the removal of the layer and thus the forming of the at least one recess, the laser beam would be focused on the layer, and the focus of the laser beam would accordingly be on and / or in the layer. In order to reduce the adhesion of the layer in the relevant region or even to bring about detachment of the layer, it would, on the other hand, be envisaged that the laser steel impinges on the layer in a defocusing manner. In this way, the layer in the relevant region is substantially only heated, but not removed.Furthermore, according to the embodiment according to the invention, it is provided that in each case two adjacent regions, between the successive processing of which a relative movement of the laser cutting tool and the substrate takes place, are processed in such a way that a tolerance compensation zone, in particular a strip-shaped tolerance compensation zone, which is initially still at least thermally connected to adjacent areas of the layer, is formed or remains between these regions. Consequently, a section of the layer extends between the adjacent regions, which compensates for the tolerances between the regions resulting from the relative movement. This opens up the possibility of taking account of higher tolerances during the relative movement than would be possible without the presence of the tolerance compensation zone. Thanks to these, it is also possible to dispense with machining the regions in such a way that they are directly adjacent to one another and the recesses which separate the regions have to overlap as precisely as possible. Due to the unnecessary overlap, impermissible damage to the substrate can also be avoided.During the processing of at least one of the adjacent regions, but in particular of both adjacent regions, the input of the energy into the respective region and thus into the tolerance compensation zone is, precisely when the recess is introduced into the layer, such that, in a development of the method according to the invention, adhesion of the layer in the tolerance compensation zone is substantially maintained. The low energy input into the layer of the tolerance compensation zone advantageously allows the following, controlled removal of the tolerance compensation zone, since an uncontrolled and undefined reduction in the adhesion or detachment is avoided. This helps maintain the desired control over the process of reducing adhesion or detachment and minimize undesirable effects. In particular, uncontrolled detachment can lead to impermissible damage to the adjacent areas or other areas of the layer. In addition, an uncontrolled detached layer of the tolerance compensation zone could be deposited again in the adjacent regions or other areas of the layer. This would potentially have adverse effects on the processing of further regions and / or could cause impermissible connections, such as short circuits between structures formed on the substrate, for example conductor tracks. In order to substantially reduce the adhesion or to remove the tolerance compensation zone, an additional energy input into the layer of the tolerance compensation zone would therefore be required.Furthermore, in order to remove the tolerance compensation zone at its two target ends lying in a main extension direction of the tolerance compensation zone, according to the invention, in particular exclusively in each case at least one linear cutout and / or interruption is introduced into the layer, which runs transversely or perpendicularly to the main extension direction of the tolerance compensation zone. The main extension direction of the tolerance compensation zone corresponds here regularly to a longitudinal extension of the tolerance compensation zone, wherein the main extension direction runs basically parallel to at least one of the main axes of a structure to be introduced into the layer. It can be considered as a continuation within the scope of the embodiment that in particular only one or two recesses per desired end are introduced into the layer. Generally speaking, because recesses are introduced, in particular exclusively at the desired ends in the main extension direction, there is advantageously a minimization of the processing time and thus of the process costs. Further recesses necessary for at least thermally separating the tolerance range along its entire outer contour would already be introduced into the layer by machining the adjacent regions. The only one-time input of energy for producing the additional recesses during the processing of the adjacent regions also prevents impermissible damage to the substrate.Thus, in one embodiment of the invention, it is also provided that the tolerance compensation zone is removed, in particular only after the processing of the adjacent regions, and the adjacent regions are thereby connected to form an overall region. Thus, control over the removal of the tolerance compensation zone is advantageously maintained and targeted control of the process of connecting the adjacent regions is made possible. This inevitably contributes to minimizing or avoiding the undesirable effects already described during the removal of the tolerance compensation zone.In a development of the method according to the invention, it is thus generally provided, in particular however in connection with the embodiment explained above, that for removing the tolerance compensation zone, the tolerance compensation zone is in particular first processed in such a way that at least one linear recess and / or interruption is introduced into the layer at least in sections along an outer contour of the tolerance compensation zone. This is effected in this case by the layer being ablated by means of the laser beam and the tolerance compensation zone thereby being at least thermally separated from adjacent areas of the layer. Subsequently, energy is again introduced into the tolerance compensation zone by means of the laser beam until a reduction in the adhesion and / or a detachment of the layer in the tolerance compensation zone is achieved. The machining of the tolerance compensation zone thus takes place in the same way as the machining of the regions to be removed. This enables efficient machining of the tolerance range and the adjacent regions with only a single device, such as a laser machining system. This integration results in significant savings in process costs because no separate equipment is needed for the machining of the tolerance compensation zone and contributes to increased efficiency of the overall process.Thus, an advantageous embodiment of the invention also lies in the fact that the linear recesses at the desired ends of the tolerance compensation zone are introduced into the layer in the extension of recesses of one of the adjacent regions or of both of the adjacent regions. This not only results in improved homogeneity of the recesses, but also minimizes the likelihood of high discontinuities or overlaps between the regions and the tolerance compensation zone.Again illustratively, it is explained in the above context that the recesses at the target ends of the tolerance compensation zone are also introduced, in particular, by removing the layer by means of the laser beam. Furthermore, in this case too, energy is subsequently preferably introduced into the tolerance compensation zone by means of the laser beam until a reduction in the adhesion and / or detachment of the layer in the tolerance compensation zone is achieved.A further embodiment of the invention is also that a scan field which can be covered by the laser cutting tool and within which the laser beam can be deflected by the laser cutting tool and which at least partially comprises a respective region during the machining thereof is designed to be slightly overlapping, pushing or slightly spaced apart from a scan field which is formed or present before the relative movement. Due to the formation of the tolerance compensation zone between adjacent regions, all the aforementioned positions of the scan fields potentially occurring after the relative movement can be compensated for here, in particular within wide limits. Thus, there is a high degree of robustness of the method with respect to potential tolerances of a device carrying out the method, e.g. of a laser cutting system.As already explained at the beginning, by removing regions of the layer, at least one structure having a defined, in particular predetermined course is formed from the layer. In this context, a development of the invention is designed in such a way that a main direction of extent, preferably a longitudinal extent of the tolerance compensation zone, is oriented parallel to at least one of the main axes of the structure determined by the course of the structure. This alignment typically contributes to a substantially optimum result in connecting the adjacent regions to an overall region. The main axes of the structure indicate the, in particular both, essential directions of extension of the structure or of parts of the structure, for example of the conductor tracks of a printed circuit board layout, and are oriented at right angles to one another.An extremely advantageous embodiment of the method according to the invention can also be seen in that a respective region is divided into partial regions for removal, wherein the partial regions are at least thermally separated from one another in that at least one linear recess and / or interruption is introduced into the layer at least in sections along an outer contour of a respective partial region by removal of the layer by means of the laser beam and energy is subsequently introduced into the respective partial region by means of the laser beam until a reduction in the adhesion and / or detachment of the layer in the respective partial region is achieved. The recesses extend substantially along in particular parallel straight lines. The subdivision of a respective region into subareas leads to increased process safety and process control. Furthermore, the input of energy necessary for reducing the adhesion and / or the detachment of the layer in a respective partial region can be dosed better than is possible for a complete region. The partial regions additionally also represent a smaller heat sink because of their smaller area in relation to a complete region, so that an occurring heat flow in particular into the substrate is reduced, so that there are lower energy losses. Thus, the necessary energy input for all partial regions of a region can also be determined to be lower in comparison with the complete region.An embodiment of the invention is also advantageous if a main direction of extent, in particular a longitudinal extent of the partial regions, is not aligned parallel to any of the main axes determined by the course of the structure and / or bisector of the main axes-of the structure. Rather, the partial regions are oriented with their main direction of extension at an acute or obtuse angle to the main axes and / or bisector of the main axes of the structure. As a result, the introduction of energy into the subareas can be further optimized, since, on account of the orientation of the subareas to be removed from the substrate in this way with respect to the structure remaining on the substrate, a heat flow from the subareas into the surrounding areas of the layer is minimized.It should also be noted that it is possible in principle for the actual or final removal of the layer of the regions, of the subareas and / or of the tolerance compensation zone from the substrate to be realized solely by the introduction of the energy into the layer of the relevant region, subarea and / or of the tolerance compensation zone.In a preferred embodiment of the invention, the, in particular actual or final, planar removal of the layer of a respective region, subregion and / or of the tolerance compensation zone from the substrate is effected, however, under an external effect, in particular differing from the energy input of the laser beam, on the layer of the region and / or subregion. The effect could be e.g. the force of gravity acting on the layer, for which purpose a layer side of the substrate is preferably oriented in the direction of the force of gravity acting. However, an effect is more advantageous which results from a targeted supply of compressed air, wherein a targeted jet of compressed air enables lifting and thus removal of the conductive layer, preferably starting from the edge to the center of the respective region, partial region and / or the tolerance compensation zone. An effect resulting from a suction and magnetic and / or electrostatic forces is likewise conceivable.It should also be explained that the width of the aforementioned partial regions and / or of the tolerance compensation zone, which is formed in particular transversely to the main direction of extension of the partial regions and / or of the tolerance compensation zone, depends substantially on the optical structure and / or-thus-on optical parameters of a laser machining system carrying out the method. In particular, the width, in particular a minimum width of the partial regions and / or of the tolerance compensation zone, is influenced by the beam diameter of the defocusing laser beam, which is consequently substantially determined by the optical structure and / or the optical parameters of the laser processing system. As already explained, the defocusing laser beam results in an energy input which leads in particular to heating and thus contributes to achieving a substantial reduction in the adhesion and / or detachment of the layer in the partial regions and / or a respective tolerance compensation zone.In addition to the beam diameter of the defocusing laser beam, the width of the partial regions and / or of the tolerance compensation zone is also dependent on a safety and / or correction factor, so that the following is for the width:The beam diameter of the defocusing laser beam depends on a focus diameter of the focused laser beam, a defocusing and a depth of focus of the laser beam around the focus point of the laser beam as follows:In this case, defocusing describes a displacement of the focal point from the focal length of a focusing lens and / or focusing optics of the laser processing system and is regularly determined from empirical values. The focus diameter of the focused laser beam is in turn dependent on a focal length of the focusing lens and / or of the focusing optics, the wavelength of the laser beam, the diffraction index M 2 and the diameter of the laser beam at the focusing lens and / or focusing optics and results in:The diffraction index M 2 represents the reciprocal of the beam quality K. The depth of field is also defined by:The following two examples again represent the determination of the width of the subareas and / or of the tolerance compensation zone on the basis of the above calculation rules: Example 1: Example 1:Diameter of laser beam at focusing lens3,0mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mmFocal length100,0mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mmWavelength: Wavelength355nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nmDiffraction index M21,3Focus diameter0,020mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mmDepth of Field1,698mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mmDefocusing3mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mmBeam diameter defocusing0,072mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mmThe correction factor is a correction factor1,5Width Width0,108mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mmExample 2:Example 2:Diameter of laser beam at focusing lens4,5mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mmFocal length100,0mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mmWavelength: Wavelength532nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nm nmDiffraction index M21,3Focus diameter0,020mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mmDepth of Field1,131mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mmDefocusing3mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mmBeam diameter defocusing0,106mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mmThe correction factor is a correction factor1,5Width Width0,159mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mm mmIt is also to be noted here that the width of the subareas and / or of the tolerance compensation zone is in particular in a range from 40 micrometers to 250 micrometers, preferably 80 micrometers to 180 micrometers and / or particularly preferably 100 micrometers to 160 micrometers.Moreover, it should be stated that a significant minimization of a heat flow caused at least by heat conduction between a respective region, subregion and / or the tolerance compensation zone and adjacent areas of the layer and / or between subregions is regarded as at least thermally separated within the scope of the invention.The invention allows various embodiments. To further clarify its basic principle, one of these is illustrated in the drawing and is described below.The drawing shows in FIGS. 1 to 3 a basic sequence of an embodiment of the method according to the invention.In this case, it is initially evident from FIG. 1 how the regions 1 are processed, such that the two depicted adjacent regions 1 or the layer 3 in these regions 1 can be removed from the substrate 2. For this purpose, at least one linear cutout 5 is introduced into the layer 3 at least in sections along the outer contour 4 of the respective region 1, wherein the two adjacent regions 1 are additionally divided into partial regions 11. This is likewise effected in that at least one linear cutout 5 is introduced into the layer 3 along the outer contour 12 of a respective partial region 11. As a result, the partial regions 11 are separated from one another and the respective complete region 1 from adjacent areas of the layer 3 at least thermally and in this case preferably completely, such that no material bond is formed within the layer 3 between the partial regions 11 and the region 1 and further areas of the layer 3 and as a result a significantly increased thermal resistance, in particular by the layer 3 itself. For this purpose, the recesses 5 are designed as interruptions, in particular in the form of cuts completely separating the layer 3.The respective recesses 5 are introduced into the layer 3 in this case by removing the layer 3 by means of a laser beam, not shown in detail, for which purpose the laser beam is focused on the layer 3. Energy is then also introduced into the respective partial region 11 and thus in each case in sections into the complete region 1 by means of the laser beam until a reduction in the adhesion and / or a detachment of the layer 3 in the respective partial region 11 and thus also in each case in sections over the complete region 1 is achieved. The energy is introduced along the illustrated heating paths 14, which are traversed by the laser beam which is in this case defocusing and are aligned in the respective main direction of extent 13 of the subareas 11. In this way, the layer 3 is only heated in the relevant region 1 or the respective partial regions 11, but is not ablated.As can also be seen from FIG. 1, the two adjacent regions 1 and thus the respectively associated partial regions 11 lie in scan fields 10 which differ from one another, wherein in each case only one of the scan fields 10 can be covered at once by a laser cutting tool which generates the laser beam. As a result, a relative movement between the laser cutting tool and the substrate 2 takes place between the machining of the two regions 1, but tolerances can be introduced into the positioning of the two adjacent regions 1 with respect to one another by this relative movement, which tolerances prevent a reliable connection of the two regions 1 during the machining of one of the regions 1 following the relative movement and / or lead to impermissible damage to the substrate 2 or to further areas of the layer 3.In order to avoid these problems, the two adjacent regions 1 are machined here in such a way that the tolerance compensation zone 6 is formed or remains between them. In this case, the adhesion of the layer 3 in the tolerance compensation zone 6 is initially maintained during the processing of the regions 1. After the machining and / or even removal of one of the regions 1 or both regions 1, the tolerance compensation zone 6 is also removed and the adjacent regions 1 are thereby connected to form an overall region. In the total region, no layer 3 is then present any longer, or the layer 3 of the relevant partial regions 11 and of the tolerance compensation zone 6 can be successively removed.How the tolerance compensation zone 6 is processed for removal can be seen in detail in FIGS. 2 and 3. For this purpose, two linear recesses 5 are introduced into the layer 3 in sections along the outer contour 7 of the tolerance compensation zone 6 and in this case, in particular, at their two target ends 9 lying in the main extension direction 8 of the tolerance compensation zone 6 per target end 9, which recesses extend transversely to the main extension direction 8 of the tolerance compensation zone 6. For the sake of illustration, only one of the two desired ends 9 is shown in FIGS. 1 to 3. The linear recesses 5 at the target ends 9 of the tolerance compensation zone 6 are also introduced into the layer 3 as extensions of recesses 5 of the two of the adjacent regions 1, so that efficient processing of the tolerance compensation zone 6 is ensured. The recesses 5 are again introduced by removal by means of the laser beam.As can also be seen from FIGS. 2 and 3, the two scanning fields 10 formed before and after the relative movement are spaced apart slightly from one another. Due to the tolerances occurring as a result of the relative movement, the recesses 5 of the tolerance compensation zone 6 starting from the regions 1 are not completely connected to one another, however, and / or do not overlap. It should be noted here that the offset between the recesses 5 in the representations of FIGS. 2 and 3 is exaggerated only for illustrative reasons and is therefore not true to scale. However, the recesses 5 nevertheless effect a thermal separation of the tolerance compensation region 6 from the further, surrounding areas of the layer 3 and the regions 1, since a sufficiently high thermal resistance is present.Thus, the introduction of energy by means of the laser beam, which takes place subsequently to the introduction of the recesses 5, along the heating path 14 which is shown in FIG. 3, also leads to a reduction in the adhesion and / or detachment of the layer 3 in the tolerance compensation zone 6, such that the layer 3 of the tolerance compensation zone 6 is removed or removed. The heating path 14 is located in the main extension direction 8 of the tolerance compensation zone 6, wherein this main extension direction 8 extends parallel to one of the main axes x, y, here the main axis y. The main axes x, y are defined by the defined, in particular predetermined, course of a structure which is formed by the removal of the regions 1 from the layer 3. The main extension direction 13 of the partial regions 11 is, on the other hand, not parallel to one of the two main axes x, y.LIST OF REFERENCE CHARACTERS1 Region 2 Substrate 3 Layer 4 Outer contour 5 Recess 6 Tolerance compensation zone 7 Outer contour 8 Main extension direction 9 Target end 10 Scan field 11 Partial region 12 Outer contour 13 Main extension direction 14 Heating path x, y Main axis

Claims

Method for removing at least one region (1) of a layer (3) applied to a substrate (2), wherein a respective region (1) to be removed is processed in such a way that at least one linear recess (5) is introduced into the layer (3) at least in sections along an outer contour (4) of the region (1), in that the layer (3) is ablated by means of a laser beam and the region (1) is thereby separated at least thermally from adjacent areas of the layer (3), wherein energy is subsequently introduced into the region (1) by means of the laser beam until a reduction in the adhesion and / or detachment of the layer (3) in the region (1) is achieved, wherein adjacent regions (1), between the successive processing of which a relative movement of a laser cutting tool and of the substrate (2) takes place, are processed in such a way, a tolerance compensation zone (6) is formed between these adjacent regions (1), characterized in that the layer (3) is processed in the tolerance compensation zone (6) for removal in such a way that at each of its two target ends (9) lying in a main direction of extension (8) at least one linear recess (5) is introduced into the layer (3) which runs transversely to the main direction of extension (8) of the tolerance compensation zone (6).Method according to Claim 1, characterized in that adhesion of the layer (3) in the tolerance compensation zone (6) is maintained during the processing of at least one of the adjacent regions (1).Method according to claim 1 or 2, characterised in that the layer (3) in the tolerance compensation zone (6) is removed after the processing of the adjacent regions (1) and the adjacent regions (1) are thereby connected to form an overall region.Method according to one of the preceding claims, characterized in that the layer (3) is processed in the tolerance compensation zone (6) for removal in such a way that at least one linear cutout (5) is introduced into the layer (3) at least in sections along an outer contour (7) of the tolerance compensation zone (6) by the layer (3) being ablated by means of the laser beam and the tolerance compensation zone (6) thereby being separated at least thermally from adjacent areas of the layer (3), wherein energy is subsequently introduced into the tolerance compensation zone (6) by means of the laser beam until a reduction in the adhesion and / or a detachment of the layer (3) in the tolerance compensation zone (6) is achieved.Method according to claim 1, characterised in that the linear recesses (5) at the desired ends (9) of the tolerance compensation zone (6) are introduced into the layer (3) as an extension of recesses (5) of one of the adjacent regions (1) or of both adjacent regions (1).Method according to one of the preceding claims, characterized in that a scanning field (10) which can be covered by the laser cutting tool and which at least partially comprises a respective region (1) during the processing thereof is designed to be slightly overlapping, pushing or slightly spaced apart from a scanning field (10) formed before the relative movement.Method according to one of the preceding claims, characterized in that at least one structure having a defined course is formed from the layer (3) by removing regions (1), wherein a main direction of extent (8) of the tolerance compensation zone (6) is aligned parallel to at least one of the main axes (x, y) of the structure determined by the course of the structure.Method according to one of the preceding claims, characterized in that a respective region (1) for removal is divided into subareas (11), wherein the subareas (11) are at least thermally separated from one another in that at least one linear cutout (5) is introduced into the layer (3) at least in sections along an outer contour (12) of a respective subarea (11) by removing the layer (3) by means of the laser beam and energy is subsequently introduced into the respective subarea (11) by means of the laser beam until a reduction in the adhesion and / or a detachment of the layer (3) in the respective subarea (11) is achieved.Method according to Claims 7 and 8, characterized in that a main direction of extent (13) of the subareas (11) is not aligned parallel to any of the main axes (x, y) determined by the course of the structure and / or bisecting lines of the main axes (x, y).Method according to one of the preceding claims, characterized in that the removal of the layer (3) of a respective region (1), partial region (11) and / or respective tolerance compensation zone (6) from the substrate (2) takes place under an external effect on the relevant layer (3).

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