Optimization of beam position images

Abstract

A method for obtaining a compensation pattern for a patterning device for workpieces, the method comprising printing (S11) a calibration pattern according to print data having a plurality of edges using a plurality of simultaneously operating exposure beams capable of scanning in a second direction. Measuring (S12) positions of the edges. Calculating (S13) deviations of the measured positions from the calibration pattern. Associating (S14) each deviation with an exposure beam used, a scanning position and a grid fraction position. Calculating (S15) edge compensation data for adjusting an edge representation of the print data prior to printing to compensate for the calculated deviations. The edge compensation data depends on the exposure beam used, the scanning position and the grid fraction position.

Description

TECHNICAL FIELD

[0001] The present technology relates to pattern printing and apparatuses therefor, and in particular to a method of obtaining a compensation pattern for a workpiece patterning apparatus, a method of calibrating print data, and a method of printing a pattern and apparatuses therefor. BACKGROUND

[0002] In today's semiconductor industry, different kinds of advanced chips and imaging devices are often manufactured using masks generated by laser-type mask writers. Today, direct writers for electronic packaging and the like are also standard configurations. In the past few years, there has also been a tremendous growth in the production of larger and more accurate displays. As a result, micro lithographic printing processes and the like are required to be faster, more accurate and less expensive.

[0003] In the field of micro lithographic printing processes, mask writers or direct writers can be based on a print head that provides one or more precise laser beams. By moving the print head or the substrate or both, the print head and the target substrate being written to can be moved relative to each other. By varying the power of the laser beams in coordination with the relative movement, an exposure pattern can be written onto the substrate.

[0004] By using a print head with multiple beams for simultaneous exposure, the overall speed can be increased. Furthermore, by also allowing the beams to be swept along a small distance perpendicular to the main direction of movement of the print head, the width of the print band is increased, which also increases the overall printing speed.

[0005] The accuracy of the printing is of utmost importance. Deviations from the intended pattern, such as critical dimension (CD) or positioning errors, even in the range of a few nanometers to a few hundred nanometers, can be detrimental or damaging to the end result. Such printing errors are often caused by imperfections in the mechanical and / or optical properties of the print head.

[0006] In published US patent US 7,919,218 B2, a method for a multiple-exposure beam lithography tool is disclosed. Therein, a method is described for patterning a workpiece covered with a layer sensitive to electromagnetic radiation by simultaneously using multiple exposure beams. It is determined whether any of the beams has an actual position different from its intended position relative to a reference beam. If a beam used when printing at the edge of a feature is not positioned correctly, the exposure dose of that beam is adjusted.

[0007] Such a correction is designed to correct for beam position errors, but deviations from the intended pattern can also depend on many other causes that cannot be compensated for by such an exposure adjustment. SUMMARY

[0008] It is a general object of the present technology to provide a means of correcting for a more general type of imperfection of a print head.

[0009] The above objects are achieved by the method and apparatus as defined in the independent claims. Preferred embodiments are defined in the dependent claims.

[0010] In general, in a first aspect, there is provided a method of obtaining a compensated pattern for a patterning device for a workpiece, the method comprising printing a calibration pattern using a plurality of simultaneously operating exposure beams separated in a first direction. The plurality of simultaneously operating exposure beams can be scanned in a second direction transverse to the first direction. The printing is in accordance with calibration pattern printing data. The calibration pattern has a plurality of edges extending along the second direction. For a plurality of scan positions in the second direction for the printed calibration pattern, a position of an edge in the first direction is measured. Deviations of the measured positions of the edges from expected positions of the edges are calculated from the calibration pattern printing data. Each deviation is associated with an exposure beam of the simultaneously operating exposure beams used for printing a respective edge, with a scan position of a plurality of positions in the second direction for printing the edge, and with a grid fraction position in the first direction of the exposure beam of the simultaneously operating exposure beams responsible for printing the respective edge. The grid fraction position is an expected position of the edge relative to an expected coverage area of the exposure beam of the simultaneously operating exposure beams responsible for printing the respective edge. Edge compensation data for adjusting a representation of the edges of the pattern printing data prior to printing to compensate for the calculated deviations is calculated. The edge compensation data depends on the used exposure beam, the scan position in the second direction, and the grid fraction position in the first direction.

[0011] In a second aspect, there is provided a method of calibrating printing data, the method comprising obtaining printing data for a pattern to be printed. The printing data is adjusted to edge-compensated printing data by using edge compensation data obtained by the method of the first aspect.

[0012] In a third aspect, there is provided a method of printing a pattern, the method comprising obtaining edge-compensated printing data for a pattern to be printed, the edge-compensated printing data being obtained using the method of the second aspect. A printing process of a workpiece at least partially covered with a cover layer sensitive to electromagnetic or electronic radiation is controlled based on the edge-compensated printing data.

[0013] In a fourth aspect, there is provided a system for obtaining a compensated pattern for a workpiece patterning device, the system comprising a printing device configured to generate a calibration pattern with a plurality of simultaneously operating exposure beams separated in a first direction. The plurality of simultaneously operating exposure beams can be scanned in a second direction transverse to the first direction. The printing device is configured to print according to calibration pattern printing data. The calibration pattern has a plurality of edges extending along the second direction. A measurement device is arranged to measure a position of the edges in the first direction for a plurality of scan positions in the second direction in the calibration pattern. A processing device is configured to calculate deviations of the measured positions of the edges from expected positions of the edges according to the calibration pattern printing data. The processing device is further configured to associate each deviation with an exposure beam of the simultaneously operating exposure beams responsible for printing a respective edge, with a scan position of the plurality of positions in the second direction in which the edge is printed, and with a grid fraction position in the first direction of the exposure beam of the simultaneously operating exposure beams responsible for printing the respective edge. The grid fraction position is an expected position of the edge relative to an expected coverage area of the exposure beam of the simultaneously operating exposure beams responsible for printing the respective edge. The processing device is further configured to calculate edge compensation data for adjusting a representation of the edges in the pattern printing data prior to printing to compensate for the calculated deviations. The edge compensation data depends on the used exposure beam, the scan position in the second direction, and the grid fraction position in the first direction.

[0014] In a fifth aspect, there is provided a device for processing printing data defining a pattern to be printed, the device comprising a processing circuitry and a memory. The memory contains instructions executable by the processing circuitry whereby the processing circuitry is operative to obtain the printing data of the pattern to be printed and to adjust the printing data to edge-compensated printing data by using edge compensation data obtained by the system for obtaining a compensated pattern in the fourth aspect.

[0015] In a sixth aspect, there is provided a printing device comprising means for processing edge-compensated printing data obtained by using the device for processing printing data in the fifth aspect. The printing device is the printing device of the system for obtaining a compensated pattern for a workpiece patterning device in the fourth aspect. The printing device further comprises a print head having a plurality of simultaneously operating exposure beams separated in a first direction. The plurality of simultaneously operating exposure beams can be scanned in a second direction transverse to the first direction. The printing device further comprises a control unit. The control unit is arranged to control operation and relative motion of the print head based on the edge-compensated printing data.

[0016] One advantage of the proposed technology is that it enables compensation for a plurality of defects in the optical and / or mechanical properties of the print head. Other advantages will become apparent on reading the detailed description. BRIEF DESCRIPTION OF DRAWINGS

[0017] The present application, together with further objects and advantages thereof, can best be understood by reference to the following description taken in conjunction with the accompanying drawings in which:

[0018] Figure 1 A printing device is schematically shown;

[0019] Figure 2 Printing with multiple exposure beams and microscanning is shown;

[0020] Figure 3 It is schematically shown how the entire surface is covered by multiple exposure beams;

[0021] Figure 4A -B shows an example of a calibration pattern line in relation to a beam grid;

[0022] Figure 5A -B shows compensation for edge deviations;

[0023] Figure 6 A part of the method for one embodiment of a printing method is shown;

[0024] Figure 7 is a flow chart of steps of one embodiment of a method for obtaining a compensation pattern for a workpiece patterning device;

[0025] Figure 8 is a flow chart of steps of one embodiment of a method for calibrating printing data;

[0026] Figure 9A -C shows edge compensation for vector printing data;

[0027] Figure 10A -C shows edge compensation for bitmap printing data;

[0028] Figure 11 is a flow chart of steps of one embodiment of a method for printing a pattern;

[0029] Figure 12 is a schematic diagram of one embodiment of a system for obtaining a compensation pattern for a workpiece patterning device;

[0030] Figure 13A -B is a schematic diagram of one embodiment of a device for processing printing data defining a pattern to be printed; and

[0031] Figure 14 is a schematic diagram of one embodiment of a printing device. DETAILED DESCRIPTION

[0032] In all drawings, like or corresponding elements are denoted by the same reference numeral.

[0033] For a better understanding of the proposed technology, it can be useful to start with a brief overview of a printing system that makes use of multiple exposure beams with a micro scanning function.

[0034] Figure 1 A printing device 1 is schematically shown, which comprises a work table 10 on which a work piece holder 12 is arranged. The work piece holder 12 is movable relative to the work table 10 along a Y direction. A work piece 20 is firmly attached to the work piece holder 12. The surface of the work piece 20 is provided with a coating that is sensitive to electromagnetic or particle radiation.

[0035] The printing device 1 further comprises a work piece patterning device 2. The work piece patterning device 2 comprises a support 30 that supports a print head 32. The print head 32 is movable along the support 30 in an X direction. The print head 32 is arranged to provide multiple exposure beams 34 that are directed towards the work piece 20 for exposure using electromagnetic or particle radiation.

[0036] The combined movement of the work piece holder 12 and the movement of the print head 32 and the micro scanning of the exposure beams 34 as will be further explained in the following enable exposure of all areas on the work piece 20 that should be exposed to radiation. In this figure, exposed areas 24 and non-exposed areas 22 are shown.

[0037] The skilled person will recognize that in other embodiments, the relative mechanical movement can also be realized in other ways, for example, the print head 30 can be moved in two dimensions and / or the work piece holder 12 can be moved in two dimensions.

[0038] In this type of printing device, multiple exposure beams and micro scanning of each exposure beam are utilized. Figure 2 This is schematically shown. Therein, a part of the work piece 20 is shown. At the moment shown, exposed areas 24 are shown with hatching, while non-exposed areas 22 are shown without hatching. Here, it is understood that the actual degree of exposure also depends on the intensity of the exposure beam at each location. However, in this figure, the "exposed areas" 24 are areas that the exposure beam has passed, or should have passed in case of intensity has been applied at that moment.

[0039] In this figure, five exposure beams 34A-E are shown. The skilled person will understand that the number of exposure beams can be chosen depending on factors such as the required printing speed, the available exposure beam size, the overall complexity, etc. However, in this exemplary illustration, five exposure beams 34A-E are chosen merely for ease of recognition of the illustration of the printing principle.

[0040] In this figure, the print head (not shown) is able to move in steps along the X direction downwards in the figure. The print head moves in regular distances, as indicated by the exposure beam step 50. At each position, the exposure beams are scanned in a so-called micro-scan along the Y direction upwards in the figure, to cover a scan width 52. In the example shown, the micro-scan is almost halfway through the micro-scan process. After the micro-scan is completed, the print head is moved another exposure beam step 50 along the X direction, and a new micro-scan is performed. As can be seen from the figure, when all exposure beams have passed a certain X position, the entire surface of the workpiece is exposed (or should have been exposed). The different exposure beams are therefore planned to fill the space between each other to make up the exposure of the entire surface. The exposure beam width 56 corresponds to the width of the micro-strip that is exposed during the micro-scan, and in order to cover the entire surface, the exposure beam width 56 multiplied by the number of exposure beams equals the exposure beam step 50. However, as can be seen, the exposure beam spacing 54 is different from the exposure beam step 50.

[0041] The movement of the print head is planned to cover the entire surface of the workpiece 20 with different exposure beams. Figure 3 An example of how this is achieved is shown. In this example, the number of exposure beams is also chosen to be five. The figure is drawn with an intended time axis pointing in the downwards direction, and the print head is moved horizontally between each row of symbols according to the exposure beam step 50. Each micro-scan is here indicated with a letter to identify the moment in time when the micro-scan is performed. The complete print is shown schematically at the top of the figure, and the number of exposure beams and the moment of printing of each part is also shown in the figure.

[0042] In Figure 4A a part of the grid of exposure beams is shown in larger scale. A line 60 to be printed is shown as covering the grid of exposure beams. In this example, the printing direction X is to the left. The line 60 to be printed therefore has a leading edge 62 and a trailing edge 64. The entire line 60 to be printed covers more than one exposure beam width 56. Furthermore, the edges 62, 64 of the line 60 to be printed are located within one respective exposure beam width 56. The edges 62, 64 of the line 60 to be printed are defined as grid fraction positions 66L, 66T relative to the intended position of the edges 55 of the intended coverage area of the exposure beam responsible for printing the edges 62, 64 of the line 60 to be printed. In this example, the leading edge 62 has a grid fraction position 66L and the trailing edge 64 has a grid fraction position 66T.

[0043] In Figure 4B another line 60 to be printed is shown, which is somewhat wider. The grid fraction positions 66L, 66T are changed accordingly.

[0044] During printing, many types of errors or defects can occur. The area that is actually illuminated can not have the geometry or dimensions that were assumed when the printing device was designed, which can lead to unexpected intensity variations along the microscanning direction and the exposure beam stepping direction. This geometric defect can also vary with the microscanning. Furthermore, different exposure beams can behave differently, the exposure beam separation can not be exactly the separation that was intended. Furthermore, the microscanning of the exposure beams can not be exactly straight, which leads to a slight curvature or tilt of the microscanning. Each of these defects can be too small to be mechanically or optically corrected by reasonable effort, but they can collectively lead to unacceptable printing errors.

[0045] All these defects will affect the printing of a perfect straight line to some extent. In Figure 5A the intended edge 64 of the straight line 60 is shown as a dashed line. One example of an actually printed line has a non-straight edge 67. The position of the actual edge 67 relative to the intended edge 64 can be determined at multiple positions in the Y direction, preferably along the entire length. Thus, the error of each point in the Y direction can be quantified. Furthermore, which exposure beam is responsible for printing the edge is known.

[0046] Features that are smaller than the exposure beam width are typically approximated by adjusting the exposure beam intensity. Features that exhibit an edge within the definition of the exposure beam width can be approximated by reducing the intensity of the corresponding exposure beam at that position. Thus, the actual behavior of a straight edge that lies within the exposure beam width can also depend on the position within the exposure beam width at which the edge is defined. In other words, the shape of the actual edge 67 can also depend on the grid fraction position of the intended edge 64. Thus, the quantified error of each point in the Y direction can also be characterized by the corresponding grid fraction position.

[0047] Correction Figure 5A One method to correct for the printing errors in is to intentionally distort the intended edge 64 such that the printing errors result in a straight actual printed edge 67. This is shown in Figure 5B . Here, the "intended edge" 69 of the pattern 61 to be printed is defined to be curved. This curvature is a compensation for the printing errors that are assumed to be present during the actual printing. Thus, the printing errors will typically give an actual printed edge 67 that appears to be straight.

[0048] The compensation that has to be made can vary with the microscanning position. The compensation can also vary depending on the exposure beam that is used to print the edge. The compensation can also vary depending on the grid fraction position of the line to be printed. This means that a specific compensation requirement can be needed for each combination of microscanning position, number of exposure beams, and grid fraction position.

[0049] By measuring the actual errors that occur when printing a straight line in the Y direction for all combinations of a set of micro-scan positions, a set of grid fraction positions, and the number of exposure beams, a data matrix of the required corrections can be constructed. When preparing to print a subsequent actual pattern, the micro-scan positions, grid fraction positions, and the number of exposure beams can be used as matrix indices to deliberately distort the intended pattern according to the data matrix.

[0050] Figure 6 A flow chart showing one embodiment of the three methods used in common to implement compensation printing is shown. The first method Ml is a method for obtaining compensation patterns for a workpiece patterning device. As explained further below, this is preferably done by printing a pattern that is intentionally straight and measuring the deviation in the final printed pattern. The deviation is used to calculate edge compensation data for adjusting the edge representation of the pattern printing data prior to printing in order to compensate for the deviation.

[0051] The second part method M2 is a method of calibrating printing data. The calibration is done according to the edge compensation data calculated in the first part method Ml. Methods Ml and M2 can be executed at the same place, even by a common processor. However, method M2 can also be executed separately in time and space from method Ml. For example, the edge compensation data can be provided to a remote processor to perform the actual calibration of the printing data.

[0052] The third part method M3 is a method for printing a pattern. Since the edge compensation data is typically unique for each printing device, part method M3 must be executed on the same printing device as used in the first part method Ml. Furthermore, the printing must be done using the calibrated printing data in part method M2. However, here the place where part method M3 is executed can be remote in time and space from the place where part method M2 is executed. Part method M2 can even be executed by another party that operates the actual printing device.

[0053] Furthermore, part method M3 can be executed multiple times using the same calibrated printing data obtained from part method M2. Likewise, part method M2 can be executed multiple times for different patterns using the same edge compensation data obtained from part method Ml.

[0054] Figure 7 A flow chart showing the steps of one embodiment of a method for obtaining compensation patterns for a workpiece patterning device is shown. In step Sll, a calibration pattern is printed using a plurality of simultaneously operating exposure beams separated in a first direction. The plurality of simultaneously operating exposure beams can be scanned in a second direction transverse to the first direction. The printing is done according to calibration pattern printing data. The calibration pattern has a plurality of edges extending along the second direction.

[0055] In step 21, the position of the edge in the first direction is measured for a plurality of scan positions in the second direction in the printed calibration pattern. The more positions in the second direction that are measured, the better the compensation for defects along the microscan will be. However, the number of measured positions also increases the size of the final compensation data.

[0056] In step S13, the deviation of the measured position of the edge from the expected position of the edge is calculated from the calibration pattern print data. In step S14, each deviation is associated with the exposure beam responsible for the printing of the respective edge in the simultaneously operating exposure beam. Each deviation is also associated with a particular scan position in the plurality of positions in the second direction in which the edge was printed. Finally, each deviation is also associated with a grid fraction position in the first direction of the exposure beam responsible for the printing of the respective edge in the simultaneously operating exposure beam. As described above, the grid fraction position is the expected position of the edge relative to the expected coverage area of the exposure beam responsible for the printing of the respective edge in the simultaneously operating exposure beam.

[0057] In step S15, edge compensation data is calculated for adjusting the edge representation of the pattern print data prior to printing to compensate for the calculated deviations. The edge compensation data depends on the used exposure beam, the scan position in the second direction, and the grid fraction position in the first direction.

[0058] As described above, the edges of the calibration pattern can be of two different types: leading edges or trailing edges. In many printing devices, the behavior of such different edges is affected by the same type of defects, which depends on the number of exposure beams, the scan position, and the grid fraction position. In this case, the same compensation data is valid for both types of edges.

[0059] However, in some printing devices, the necessary compensation can also depend on whether the edge is a leading edge or a trailing edge. Therefore, in one embodiment, the association of each deviation also includes associating each deviation with a leading edge or a trailing edge with respect to the first direction. Thereby, the edge compensation data also depends on whether the edge to be compensated is a leading edge or a trailing edge.

[0060] The calibration pattern should comprise edges directed in the second direction, i.e. parallel to the microscanning direction. In a preferred embodiment, to make efficient use of space, the calibration pattern comprises lines in the second direction. In this way, it is easy to provide edges at the positions of the different exposure beams. In other words, the width and position of the lines in the calibration pattern are adapted to cover all simultaneously operating exposure beams that will be involved in the creation of at least one edge of said calibration pattern. Preferably, for each exposure beam, edges are also provided at different grid fraction positions. The more different grid fraction positions of edges are provided in the first direction, the better the compensation for imperfections of the microscanning. However, the number of grid fraction positions also increases the size of the final compensation data and increases the time to perform the calibration. Therefore, the number of grid fraction positions used is preferably determined as a trade-off between time, data size and correction quality.

[0061] In a preferred embodiment, the calibration pattern comprises a reference line. The width of the reference line ensures that the leading edge and the trailing edge are provided by one and the same scan in the second direction by a plurality of simultaneously operating exposure beams. In other words, both edges of the reference line should be printed without moving the print head in the X direction. In contrast, the interior of the reference line can be provided by a preceding or a subsequent scan by any exposure beam. By printing the edges in one and the same scan, any imperfections of the movement of the print head in the X direction can be excluded.

[0062] Figure 8 A flow chart showing the steps of a method for calibrating print data is shown. In step S21, print data of a pattern to be printed is obtained. In step S22, the print data is adjusted to edge compensated print data using edge compensation data. The edge compensation data is obtained using a part method M1, for example as shown in Figure 6 Figure 7

[0063] Typically, the print data is initially provided as vector print data. The objects to be printed are then defined using parameters that typically describe the type, size and position of the objects. For example, if a square is to be printed, then a definition code for a square plus for example width, height, rotation and corner positions in the X and Y direction are sufficient to define the object. Alternatively, the edges of the object can be defined by a shape, a start position and an end position. In this way, a square can be characterized by four straight lines connecting four points. Vector print data is a convenient way to describe relatively simple shapes in a very data efficient way. This is schematically shown in Figure 9A

[0064] ​​​In one embodiment, the edge compensation data is vector edge compensation data. Such vector edge compensation data comprises data defining a change of shape of a pattern structure representing an edge in the first direction in the vector print data. This means that the position, the size and even the shape can need to be redefined.

[0065] In one particular embodiment, the vector edge compensation data comprises data causing the edge to be moved in the first direction according to the calibration pattern print data, the amount of movement of this movement being equal but opposite compared to the corresponding deviation of the measured position of the edge from the expected position of the edge. Figure 9B In Fig. 6, the print result of the calibration pattern of the same area is shown. The lines in the printed calibration pattern are slanted with respect to the expected lines shown as dashed lines.

[0066] In Fig. 7, the compensated vector print data is shown, in which the sides of the original square are slanted to compensate for the error detected during the calibration support. Figure 9C Note that the errors shown in Figs. 5 and 6 are greatly exaggerated in order to be able to visually show the compensation strategy.

[0067] Figure 9A and 9B In Fig. 6, the print result of the calibration pattern of the same area is shown. The lines in the printed calibration pattern are slanted with respect to the expected lines shown as dashed lines.

[0068] Please return to Figure 8 In step S22, the edge compensation data in the adjustment is vector edge compensation data. This vector edge compensation data comprises data defining a change of shape of a pattern structure representing an edge in the first direction in the vector print data. Thus, the step S22 of adjusting the print data comprises changing the shape of the pattern structure in the vector print data according to the vector edge compensation data obtained with the above ideas.

[0069] In one preferred embodiment based on vector print data, the vector edge compensation data comprises data causing the edge to be moved in the first direction according to the calibration pattern print data, the amount of movement of this movement being equal but opposite compared to the corresponding deviation of the measured position of the edge from the expected position of the edge.

[0070] It will be understood by anyone skilled in the art that depending on the actual compensation performed, the final shape of the object of the compensated vector print data can be rather complex and can be difficult to define with simple vectors. However, in most printing devices, the vector print data is converted into bitmap print data before the actual printing is performed. There are also printing devices that require the original data to be provided in bitmap print data format from the start. In both cases, the compensation of the present invention can be performed in the bitmap print data.

[0071] Figure 10A ​An example of bitmap printing data is shown. Here, the bit matrix labeled with a certain intensity defines a square. Compensation in the bitmap printing data can be done by adjusting the intensity setting of the bits near the edge under consideration. Figure 10B The measured deviation between the expected calibration pattern and the measured calibration pattern is shown. Figure 10C Compensated bitmap printing data is shown, where the intensity of the bits near the edge is adjusted.

[0072] In other words, in one embodiment, the edge compensation data is bitmap edge compensation data. The bitmap edge compensation data comprises data defining intensity adjustments of individual bits in the bitmap printing data representing an edge in the first direction.

[0073] Preferably, the bitmap edge compensation data comprises data defining an increasing amount of intensity adjustment of individual bits in the bitmap printing data representing an edge in the first direction, if the edge of the pattern printed according to the calibration pattern printing data lies inside the respective edge position. The bitmap edge compensation data comprises data defining a decreasing amount of intensity adjustment of individual bits in the bitmap printing data representing an edge in the first direction, if the edge of the pattern printed according to the calibration pattern printing data lies outside the respective edge position.

[0074] Preferably, the increasing or decreasing amount of intensity is dependent on the magnitude of the respective deviation of the measured position of the edge from the expected position of the edge, respectively, according to the calibration pattern printing data.

[0075] In one embodiment, the bitmap edge compensation data is provided as a data matrix, which uses the exposure beam used, the scan position in the second direction and the grid fraction position in the first direction as matrix indices.

[0076] Again, referring back to Figure 8 In this embodiment, the edge compensation data is bitmap edge compensation data. Preferably, the bitmap edge compensation data comprises data defining intensity adjustments of individual bits in the bitmap printing data representing an edge in the first direction. The step of adjusting S22 the printing data thus comprises adjusting the intensity of individual bits in the bitmap printing data according to the bitmap edge compensation data. The bitmap edge compensation data is preferably obtained using a method according to the ideas shown above.

[0077] Preferably, the bitmap edge compensation data is provided as a data matrix. The step of adjusting S22 the printing data comprises retrieving the intensity adjustment value for individual bits in the bitmap printing data using the exposure beam used, the scan position in the second direction and the grid fraction position in the first direction as matrix indices.

[0078] Figure 11A flow chart showing steps of one embodiment of a method for printing a pattern. In step S31, edge compensated printing data obtained using a method for calibrating printing data is obtained. The method for calibrating printing data is Figure 2 part method M2, and is preferably performed according to Figure 8 In step S32, a printing process of a workpiece is controlled based on the edge corrected printing data. The workpiece is a workpiece at least partially covered with a coating that is sensitive to electromagnetic or electronic radiation.

[0079] Preferably, the step of controlling S32 the printing process comprises controlling the simultaneously operating exposure beams to provide microscanning in a second direction while scanning along a first direction, resulting in a scan band.

[0080] More preferably, the step of controlling S32 the printing process further comprises generating a plurality of scan stripes displaced in the second direction.

[0081] In one embodiment, the printing process is a microlithographic printing process. Preferably, the printing process is a mask write process or a direct write process.

[0082] Figure 12 One embodiment of a system 70 for obtaining a compensation pattern for a workpiece patterning device is schematically shown. The system 70 for obtaining a compensation pattern for a workpiece patterning device comprises a printing device 1 configured to generate a calibration pattern with a plurality of simultaneously operating exposure beams separated in a first direction. The plurality of simultaneously operating exposure beams can be scanned in a second direction transverse to the first direction. In Figure 1 One example of such a printing device 1 is also shown in the figure. The printing device is configured to print according to the calibration pattern printing data. The calibration pattern has a plurality of edges extending in the second direction.

[0083] The system 70 for obtaining a compensation pattern for a workpiece patterning device further comprises a measurement device 4 arranged to measure the position of the edges in the first direction for a plurality of scan positions in the second direction in the calibration pattern. In this illustration, the measurement device 4 is shown as a separate unit arranged on a support 30 of the printing device 1. However, the measurement device 4 can also be provided as a fully independent unit, or as an integral part of the printing head 32. Also, the measurement device 4 is well known in the art and can be obtained in many different configurations. However, such details of the measurement device 4 are not essential, as long as the measurement device provides the edge positions, data representing such edge positions, or data from which such edge positions can be derived. Therefore, the measurement device will not be further explained.

[0084] The system 70 for obtaining a compensation pattern for a workpiece patterning device further comprises a processing device 6. The processing device 6 is connected to the printing device 1 and to the measuring device 4. The processing device 6 is configured to calculate, from the calibration pattern printing data, deviations of the measured positions of the edges relative to the expected positions of the edges. The processing device 6 is further configured to associate each deviation with the exposure beam of the simultaneously operating exposure beams responsible for printing the respective edge, with a scan position in the plurality of positions in the second direction in which the edge is printed, and with a grid fraction position in the first direction of the exposure beam of the simultaneously operating exposure beams responsible for printing the respective edge. As described before, the grid fraction position is the expected position of the edge relative to the expected coverage area of the exposure beam of the simultaneously operating exposure beams responsible for printing the respective edge.

[0085] The processing device 6 is further configured to calculate edge compensation data for adjusting the edge representation of the pattern printing data prior to printing to compensate for the calculated deviations. The edge compensation data depends on the used exposure beam, the scan position in the second direction, and the grid fraction position in the first direction.

[0086] In one embodiment, the edge compensation data is bitmap edge compensation data comprising data defining intensity adjustments of individual bits of the bitmap printing data representing the edge in the first direction. Preferably, the bitmap edge compensation data comprises data defining an increasing amount of intensity adjustments of individual bits of the bitmap printing data representing the edge in the first direction, if the edge of the pattern printed from the calibration pattern printing data is located inside the respective edge position. Similarly, the bitmap edge compensation data comprises data defining a decreasing amount of intensity adjustments of individual bits of the bitmap printing data representing the edge in the first direction, if the edge of the pattern printed from the calibration pattern printing data is located outside the respective edge position. More preferably, the increasing or decreasing amount of intensity depends on the magnitude of the respective deviation of the measured position of the edge relative to the expected position of the edge, respectively, according to the calibration pattern printing data.

[0087] In one embodiment, the bitmap edge compensation data is provided as a data matrix, which data matrix has the used exposure beam, the scan position in the second direction, and the grid fraction position in the first direction as matrix indices.

[0088] In another embodiment, the edge compensation data is vector edge compensation data comprising data defining a shape change of a pattern structure representing the edge in the first direction in the vector printing data. Preferably, the vector edge compensation data comprises data causing the edge to move in the first direction according to the calibration pattern printing data by an amount of movement equal but opposite in direction compared to the respective deviation of the measured position of the edge relative to the expected position of the edge.

[0089] Figure 13AAn embodiment of an apparatus 80 for processing print data defining a pattern to be printed is schematically shown. The apparatus 80 for processing print data defining a pattern to be printed comprises a processing circuitry 8 and a memory 7. The memory 7 comprises instructions executable by the processing circuitry 8, whereby the processing circuitry 8 is operative to obtain print data of a pattern to be printed and to adjust the print data to edge-compensated print data by edge-compensation data. For example, according to an embodiment, the edge-compensation data is obtained by the system 70 for obtaining a compensation pattern. Figure 12

[0090] In an embodiment, the processing circuitry 8 is operative to adjust the print data to edge-compensated print data with bitmap edge-compensation data obtained by the system 70. The processing circuitry 8 is further operative to adjust intensities of individual bits in the bitmap print data representing an edge in the first direction. Preferably, the bitmap edge-compensation data is provided as a data matrix, wherein the processing circuitry 8 is further operative to retrieve the intensity adjustments from the data matrix using the exposure beam, the scan position in the second direction and the grid fraction position in the first direction as matrix indices.

[0091] In another embodiment, the processing circuitry 8 is operative to adjust the print data to obtain a compensation pattern with vector edge-compensation data obtained by the system 70. The vector edge-compensation data comprises data in the vector print data defining a change of shape of a pattern structure representing an edge in the first direction. Preferably, the vector edge-compensation data comprises data causing the edge to be moved in the first direction according to the calibration pattern print data, the amount of movement being equal but opposite in direction compared to the respective deviation of the measured position of the edge from the expected position of the edge. The processing circuitry is operative to adjust the vector print data accordingly.

[0092] In Figure 13A an embodiment, the apparatus 80 for processing print data defining a pattern to be printed is shown as a separate unit in communication with the system 70 for obtaining a compensation pattern. However, as Figure 13B schematically shown, the apparatus 80 for processing print data defining a pattern to be printed can also be part of and / or integrated in the system 70 for obtaining a compensation pattern. Preferably, the processing circuitry 8 constitutes part of the processing apparatus 6.

[0093] Figure 14 ​An embodiment of a printing device 1 is schematically shown. The printing device 1 comprises a device 9 for processing edge-compensated printing data obtained by a device 80 for processing printing data according to the ideas set out above. The printing device 1 is a printing device of a system 70 for obtaining a compensation pattern of a patterning device for a workpiece. The printing device 1 comprises a print head 32 having a plurality of simultaneously operating exposure beams separated in a first direction. The plurality of simultaneously operating exposure beams can be scanned in a second direction transverse to the first direction. The printing device 1 further comprises a control unit 5. The control unit 5 is arranged to control the operation and relative movement of the print head based on the edge-compensated printing data.

[0094] In Figure 14 the control unit 5 and the device 9 for processing edge-compensated printing data are shown as separate units. However, they can also be integrated into one common unit. Further, the processing circuitry of the device 80 for processing printing data can be integrated in the same unit as the control unit 5 and / or the device 9 for processing edge-compensated printing data. Further, the processing device 6 can be part of the common unit.

[0095] The above-described embodiments should be understood as a few illustrative examples of the present application. Those of skill in the art will understand, upon consideration of the disclosure, that various modifications, combinations, and enhancements can be made to these illustrative examples and that some changes can be desirable in certain circumstances. Accordingly, the disclosure is not intended to be limited to the examples disclosed herein, but has wide applicability to any printing device that processes edge-compensated printing data. In particular, different parts of different embodiments can be combined in other configurations, as technically appropriate, without departing from the scope of the present application. The scope of the application is, therefore, indicated by the appended claims, rather than by the foregoing description.

Claims

1. A method for obtaining a compensation pattern for a workpiece patterning device, comprising the following steps: - A calibration pattern (60) is printed (S11) using multiple simultaneously operating exposure beams (34; 34A-E) separated in a first direction (X); The plurality of simultaneously operating exposure beams (34; 34A-E) are capable of scanning in a second direction (Y) transverse to the first direction (X); The printing was performed based on calibration pattern printing data; The calibration pattern (60) has a plurality of edges (62, 64) extending in the second direction; - In the printed calibration pattern, the position of the edge (67) in the first direction is measured (S12) for multiple scan positions in the second direction (Y); - Calculate (S13) the deviation of the measured position of the edge (67) relative to the expected position of the edge (62, 64) based on the calibration pattern printing data; - Associate each deviation with the exposure beam (34A-E) responsible for printing the corresponding edge in the simultaneously operating exposure beams (34; 34A-E) (S14), with the scan position of a plurality of positions where the edge is printed in the second direction (Y) (S14), and with the grid fraction position (66L, 66T) in the first direction (X) of the exposure beam (34A-E) responsible for printing the corresponding edge in the simultaneously operating exposure beams (34; 34A-E) (S14); The grid fractional positions (66L, 66T) are the expected positions of the edges relative to the edge (55) of the expected coverage area of ​​the exposure beam (34A-E) responsible for printing the corresponding edge in the simultaneously operating exposure beams (34; 34A-E); - Calculate (S15) edge compensation data for adjusting the edge representation of the pattern printing data before printing to compensate for the deviation of the calculation; The edge compensation data depends on the exposure beam used (34A-E), the scan position in the second direction (Y), and the grid fraction position (66L, 66T) in the first direction (X).

2. The method as described in claim 1, characterized in that, The edge compensation data is bitmap edge compensation data, which includes data on intensity adjustment of each bit representing the edge in the first direction (X) in the bitmap printing data.

3. The method as described in claim 2, characterized in that: If the edge of the pattern printed according to the calibration pattern printing data is located inside the corresponding edge position, then the bitmap edge compensation data includes data that defines an increase in the intensity adjustment of each bit of the edge in the first direction in the bitmap printing data; and If the edge of the pattern printed according to the calibration pattern printing data is located outside the corresponding edge position, then the bitmap edge compensation data includes data that defines the reduction amount of intensity adjustment of each bit of the edge in the bitmap printing data in the first direction.

4. The method as described in claim 3, characterized in that, According to the calibration pattern printing data, the increase or decrease in intensity depends on the magnitude of the corresponding deviation of the measured position of the edge relative to the expected position of the edge.

5. The method as described in claim 2, characterized in that, The bitmap edge compensation data is provided as a data matrix, which uses the exposure beam used, the scan position in the second direction, and the grid fraction position in the first direction as matrix indices.

6. The method as described in claim 1, characterized in that, The edge compensation data is vector edge compensation data, which includes data in the vector printing data that defines the shape changes of the pattern structure representing the edge in the first direction.

7. The method as described in claim 6, characterized in that, The vector edge compensation data includes data that causes the edge to move along the first direction according to the calibration pattern printing data, the amount of movement being equal to but in the opposite direction to the corresponding deviation of the measured position of the edge relative to the expected position of the edge.

8. The method according to any one of claims 1 to 7, characterized in that, The association of each deviation also includes associating each deviation with a front edge or a back edge with respect to the first direction, whereby the edge compensation data also depends on whether the edge to be compensated is a front edge or a back edge.

9. The method according to any one of claims 1 to 7, characterized in that, The calibration pattern includes lines in the second direction (Y).

10. The method as described in claim 9, characterized in that, The calibration pattern includes reference lines whose width ensures that the leading and trailing edges (62, 64) can be provided by the same scan in the second direction (Y) of the plurality of simultaneously operating exposure beams (34A-E).

11. The method as described in claim 9, characterized in that, The width and position of the lines in the calibration pattern (60) are adapted to cover all the exposure beams (34A-E) that operate simultaneously in the generation of at least one edge (62, 64) of the calibration pattern.

12. A method for calibrating print data, comprising the following steps: - Obtain (S21) printing data for the pattern to be printed; as well as - The printing data is adjusted (S22) to edge-compensated printing data using the edge compensation data obtained by the method as described in claim 1.

13. A method for printing a pattern, comprising the following steps: - Obtain (S31) edge-compensated printing data of the pattern to be printed obtained by using the method as described in claim 12; as well as - A printing process for a workpiece that is at least partially covered with a coating sensitive to electromagnetic or electronic radiation, based on the edge-compensated printing data control (S32).

14. A system (2) for obtaining a compensation pattern for a workpiece patterning device, comprising: -Configured to use multiple simultaneously operating exposure beams (34) separated in a first direction (X); 34A-E) A printing apparatus (1) that generates calibration patterns (60); The plurality of simultaneously operating exposure beams (34; 34A-E) are capable of scanning in a second direction (Y) transverse to the first direction (X); The printing apparatus (1) is configured to perform the printing according to calibration pattern printing data; The calibration pattern (60) has a plurality of edges (62, 64) extending in the second direction (Y); - A measuring device (4) arranged to measure the position of the edge in the first direction for a plurality of scanning positions in the second direction of the printed calibration pattern; as well as -A processing device (6) configured to calculate the deviation of the measured position of the edge relative to the expected position of the edge based on the calibration pattern printing data; The processing device (6) is further configured to associate each deviation with the exposure beam (34A-E) responsible for printing the corresponding edge in the simultaneously operating exposure beams (34; 34A-E), with the scan position of a plurality of positions where the edge is printed in the second direction (Y), and with the grid fraction position (66L, 66T) in the first direction of the exposure beam (34A-E) responsible for printing the corresponding edge in the simultaneously operating exposure beams (34; 34A-E); The grid fractional positions (66L, 66T) are the expected positions of the edges relative to the edges of the expected coverage areas of the exposure beams (34A-E) responsible for printing the corresponding edges in the simultaneously operating exposure beams (34; 34A-E); The processing device (6) is also configured to calculate edge compensation data for adjusting the edge representation of the pattern printing data before printing to compensate for deviations in the calculation; The edge compensation data depends on the exposure beam used (34A-E), the scan position in the second direction (Y), and the grid fraction position (66L, 66T) in the first direction (X).

15. An apparatus (80) for processing printing data defining a pattern to be printed, comprising: - Processing circuit (8); as well as -Memory (7); The memory (7) includes instructions that can be executed by the processing circuit (8), thereby enabling the processing circuit (8) to: Obtain the printing data of the pattern to be printed; as well as The printing data is adjusted to edge-compensated printing data using edge compensation data obtained by the system for obtaining a workpiece patterning device as described in claim 14.

16. A printing apparatus (1), comprising: -A device (9) for processing edge-compensated printing data obtained using the device (80) for processing printing data defining a pattern to be printed as described in claim 15; The printing device (1) therein is the printing device (1) of the system for obtaining the compensation pattern of the workpiece patterning device as described in claim 14; - A printhead (32) having multiple simultaneously operating exposure beams (34; 34A-E) separated in a first direction (X); The plurality of simultaneously operating exposure beams (34; 34A-E) are capable of scanning in a second direction (Y) transverse to the first direction (X); as well as - Control unit (5); The control unit (5) is arranged to control the operation and relative movement of the print head (32) based on the edge-compensated print data.

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