Drawing apparatus and drawing method

Abstract

The invention relates to a drawing apparatus. An evaluation value acquisition unit (803) obtains a pattern position, which is the position of a calibration pattern in each of a plurality of detection images obtained by a calibration camera (53), for a detection image group, which is a set of two or more predetermined number of detection images included in the plurality of detection images, and obtains a variation evaluation value. The variation evaluation value indicates the magnitude of the deviation of the predetermined number of pattern positions in the detection image group. When the variation evaluation value is equal to or less than a predetermined threshold value, a correction image group setting unit (804) sets the detection image group as a correction image group. The correction information acquisition unit (805) acquires correction information for correcting the irradiation position of light from the drawing head (41) on the basis of the predetermined number of pattern positions in the correction image group. As a result, it is possible to calibrate the drawing head (41) with high precision while suppressing an increase in cycle time.

Description

[0001] CROSS - REFERENCE TO RELATED APPLICATIONS

[0002] This application claims the benefit of the priority of Japanese Patent Application JP2024 - 002818 filed on January 11, 2024, and incorporates the entire disclosure of that application herein. TECHNICAL FIELD

[0003] The present invention relates to a technique for irradiating a substrate with light to draw a pattern. BACKGROUND ART

[0004] Conventionally, in the process of drawing a pattern on a printed substrate, a semiconductor substrate, etc. (hereinafter referred to as "substrate"), the following drawing apparatus has been used: modulated light is irradiated onto a photosensitive material formed on the substrate, and the pattern is directly drawn by scanning the irradiated area of the light.

[0005] In such a drawing apparatus, due to the temperature rise of the drawing head or the temperature change in the periphery of the apparatus with the passage of time from the start of drawing, the irradiation position of the light from the drawing head on the substrate changes, and sometimes an offset in the position of the pattern drawn on the substrate occurs. Therefore, in Japanese Unexamined Patent Application Publication No. 2014 - 197136 (Document 1), the following calibration method has been proposed: the variation data of the above - mentioned irradiation position caused by the temperature change is acquired in advance, and the irradiation position is corrected according to the measured temperature. However, in the indirect calibration using temperature as an index, sometimes the calibration accuracy is insufficient.

[0006] On the other hand, different from the case of indirectly obtaining the variation of the irradiation position according to the temperature as in Document 1, there is also a known calibration method of directly obtaining the variation of the irradiation position by observing the light from the drawing head using a camera. In this case, the stage on which the substrate is mounted is moved, and the camera is positioned vertically below the drawing head for calibration. After the calibration is completed, the stage is moved to a position vertically below the drawing head for drawing on the substrate. Therefore, one calibration takes a long time. Therefore, from the viewpoint of shortening the takt time (i.e., the time taken for the drawing operation on one substrate, also referred to as the cycle time), it is difficult to perform calibration every time the drawing on one substrate is completed, and calibration is performed every time a predetermined drawing time elapses, or every time the drawing on two or more predetermined number of substrates is completed.

[0007] Therefore, in the drawing apparatus as described above, it is desired to further improve the drawing position accuracy. On the one hand, it is necessary to increase the frequency of calibration, and on the other hand, it is also necessary to suppress the reduction of productivity. In addition, in this drawing apparatus, improvement of calibration accuracy is also required. SUMMARY OF THE INVENTION

[0008] The present invention relates to a drawing device that irradiates a substrate with light to draw a pattern, and aims to suppress an increase in cycle time and perform calibration of a drawing head with high precision.

[0009] Mode 1 of the present invention is a drawing device that irradiates a substrate with light to draw a pattern, and includes: a stage provided with a substrate holding portion for holding a substrate; a drawing head that irradiates the substrate with modulated light; a main scanning mechanism that relatively moves the stage relative to the drawing head in a main scanning direction parallel to the upper surface of the substrate; a scale portion provided on the stage and located at a calibration position below the drawing head when the stage is at a loading position where the substrate is loaded and unloaded with respect to the substrate holding portion; a calibration camera that, when the scale portion is at the calibration position, captures a calibration pattern irradiated from the drawing head to the scale portion, and obtains a plurality of detection images each including the scale portion and the calibration pattern; an evaluation value acquisition portion that, for a set of two or more detection images included in the plurality of detection images obtained by the calibration camera, that is, a detection image group, obtains the position of the calibration pattern in each detection image, that is, the pattern position, and obtains a variation evaluation value indicating the magnitude of the deviation of the specified number of the pattern positions in the detection image group; a correction image group setting portion that, when the variation evaluation value is equal to or less than a specified threshold, sets the detection image group as a correction image group; a correction information acquisition portion that, based on the specified number of the pattern positions of the correction image group, obtains correction information for correcting the irradiation position of the light from the drawing head; and a drawing control portion that, by controlling the drawing head and the main scanning mechanism based on drawing data and the correction information, relatively moves the substrate relative to the drawing head in the main scanning direction and causes the drawing head to perform drawing on the substrate.

[0010] According to the present invention, it is possible to suppress an increase in cycle time and perform calibration of a drawing head with high precision.

[0011] Mode 2 of the present invention is based on the drawing device of Mode 1, and when the variation evaluation value is greater than the threshold, the calibration camera obtains a new plurality of detection images after a specified standby time has elapsed since the end of the capture of the plurality of detection images, the evaluation value acquisition portion obtains a new variation evaluation value for a set of the specified number of detection images included in the new plurality of detection images, that is, a new detection image group, and when the new variation evaluation value is equal to or less than the threshold, the correction image group setting portion sets the new detection image group as the correction image group.

[0012] The method 3 of the present invention is based on the description device of method 2, wherein the deviation of the specified number of the pattern positions in the detected image group is caused by the vibration of the stage when the substrate is carried into the substrate holding part, and the standby time is longer than the duration of the vibration of the stage when the substrate is carried into the substrate holding part.

[0013] The method 4 of the present invention is based on the description device of method 3, wherein when the substrate is carried into the substrate holding part, one of the automatic loading by the loading device and the manual loading by the operator is performed, and the standby time can be switched between a first standby time corresponding to the automatic loading and a second standby time corresponding to the manual loading and different from the first standby time.

[0014] The method 5 of the present invention is based on the description device of method 1, wherein the number of the plurality of detected images acquired by the calibration camera is larger than the number of the detected images included in the detected image group. When the variation evaluation value is greater than the threshold value, the evaluation value acquisition unit selects a set of the specified number of detected images different from the detected image group, that is, a new detected image group, from the plurality of detected images, calculates a new variation evaluation value for the new detected image group, and when the new variation evaluation value is equal to or less than the threshold value, the correction image group setting unit sets the new detected image group as the correction image group.

[0015] The method 6 of the present invention is based on the description device of method 5, wherein the deviation of the specified number of the pattern positions in the detected image group is caused by the vibration of the stage when the substrate is carried into the substrate holding part, and the time required to acquire the plurality of detected images by the calibration camera is longer than the duration of the vibration of the stage when the substrate is carried into the substrate holding part.

[0016] Aspect 7 of the present invention depicts an apparatus according to any one of Aspects 1 to 6, wherein a plurality of drawing heads that include the drawing head and irradiate the substrate with modulated light respectively are arranged above the scale portion in an arrangement direction parallel to the upper surface of the substrate and inclined with respect to the main scanning direction. In a state where the scale portion is located at the calibration position, the calibration camera moves in the arrangement direction and sequentially captures a plurality of calibration patterns irradiated from the plurality of drawing heads to the scale portion respectively, thereby obtaining a plurality of detection images corresponding to each of the plurality of drawing heads. The evaluation value acquisition unit calculates the variation evaluation value for each of the plurality of drawing heads. The correction image group setting unit sets the correction image group for each of the plurality of drawing heads. The correction information acquisition unit acquires the correction information for each of the plurality of drawing heads. The drawing control unit controls the plurality of drawing heads and the main scanning mechanism based on the drawing data and the correction information for each of the plurality of drawing heads, thereby performing drawing on the substrate.

[0017] Aspect 8 of the present invention is the drawing apparatus according to Aspect 7, wherein the time required from obtaining the plurality of detection images corresponding to each of the plurality of drawing heads by the calibration camera to setting the correction image group for each of the plurality of drawing heads is less than or equal to the time required to remove one substrate from the substrate holding unit and load a new substrate into the substrate holding unit.

[0018] Aspect 9 of the present invention is the drawing apparatus according to Aspect 7 (it can also be according to Aspect 7 or 8), wherein the calibration camera obtains the plurality of detection images corresponding to each of the plurality of drawing heads each time a substrate is loaded into the substrate holding unit.

[0019] Embodiment 10 of the present invention is a drawing method in which a substrate is irradiated with light to draw a pattern, including: a) a process of photographing a calibration pattern irradiated from the drawing head to the calibration part at a calibration position below the drawing head while the stage provided with the substrate holding part and the scale part is at the loading position where the substrate is loaded and unloaded with respect to the substrate holding part, and acquiring a plurality of detection images respectively including the scale part and the calibration pattern; b) a process of, for a set of two or more specified number of detection images included in the plurality of detection images acquired in the process a), i.e., a detection image group, obtaining the position of the calibration pattern in each detection image, i.e., the pattern position, and obtaining a variation evaluation value representing the magnitude of the deviation of the specified number of the pattern positions in the detection image group; c) a process of setting the detection image group as a correction image group when the variation evaluation value is equal to or less than a specified threshold; d) a process of obtaining correction information for correcting the irradiation position of the light from the drawing head based on the specified number of the pattern positions of the correction image group; and e) a process of irradiating the substrate with the modulated light from the drawing head while the substrate relatively moves in the main scanning direction with respect to the drawing head based on the drawing data and the correction information, and performing the drawing of the substrate.

[0020] The above objects and other objects, features, aspects and advantages will be clarified with reference to the accompanying drawings and the following detailed description of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 is a perspective view showing a drawing apparatus according to an embodiment.

[0022] Figure 2 is an enlarged plan view showing the vicinity of the calibration part.

[0023] Figure 3 is a diagram showing the internal structures of the calibration part and the drawing head.

[0024] Figure 4 is a diagram showing the structure of a computer.

[0025] Figure 5 is a block diagram showing the functions of the control part.

[0026] Figure 6 is a diagram showing the flow of pattern drawing.

[0027] Figure 7A is a front view schematically showing the main structure of the drawing apparatus.

[0028] Figure 7B is a front view schematically showing the main structure of the drawing apparatus.

[0029] Figure 7C It is a front view schematically showing the main structure of the drawing device.

[0030] Figure 7D It is a front view schematically showing the main structure of the drawing device.

[0031] Figure 7E It is a front view schematically showing the main structure of the drawing device.

[0032] Figure 7F It is a front view schematically showing the main structure of the drawing device.

[0033] Figure 7G It is a front view schematically showing the main structure of the drawing device.

[0034] Figure 7H It is a front view schematically showing the main structure of the drawing device.

[0035] Figure 8 It is a diagram showing the process of calibration based on the first calibration method.

[0036] Figure 9 It is a diagram showing the process of calibration based on the second calibration method.

[0037] Explanation of reference numerals

[0038] 1 Drawing device

[0039] 9 Substrate

[0040] 21 Stage

[0041] 23 First moving mechanism

[0042] 25 Substrate holding part

[0043] 41 Drawing head

[0044] 52 Scale part

[0045] 53 Calibration camera

[0046] 91 Upper surface (of the substrate)

[0047] 95 Loading device

[0048] 803 Evaluation value acquisition unit

[0049] 804 Correction image group setting unit

[0050] 805 Correction information acquisition unit

[0051] 807 Drawing control unit

[0052] Steps S11 to S14, S21 to S26, S29, S31 to S36, S241 to S242 Detailed implementation manner

[0053] Figure 1 FIG. is a perspective view of a drawing apparatus 1 showing an embodiment of the present invention. The drawing apparatus 1 is a direct drawing apparatus that irradiates a photosensitive material on a substrate 9 with spatially modulated substantially beam-like light and forms a pattern by scanning the irradiation area of the light on the substrate 9. In Figure 1 , three mutually orthogonal directions are indicated by arrows as the X direction, the Y direction, and the Z direction. In Figure 1 the example shown, the X direction and the Y direction are mutually perpendicular horizontal directions, and the Z direction is the vertical direction (i.e., the up and down direction). The same applies to other figures.

[0054] The substrate 9 is, for example, a substantially rectangular flat printed circuit board. On the main surface on the (+Z) side of the substrate 9 (hereinafter, also referred to as "upper surface 91"), a resist film formed of a photosensitive material is provided on a copper layer. In the drawing apparatus 1, a circuit pattern is drawn (i.e., formed) on the resist film of the substrate 9. It should be noted that the type and shape of the substrate 9 can be variously changed.

[0055] As Figure 1 shown, the drawing apparatus 1 includes a stage 21, a stage moving mechanism 22, an alignment unit 3, a drawing unit 4, a calibration unit 5, and a control unit 8. The control unit 8 controls the stage moving mechanism 22, the alignment unit 3, the drawing unit 4, the calibration unit 5, etc.

[0056] The drawing apparatus 1 further includes a housing 6. The housing 6 is, for example, a substantially rectangular parallelepiped exterior member that houses the stage moving mechanism 22, the alignment unit 3, the drawing unit 4, the calibration unit 5, etc. inside. In Figure 1 , the housing 6 is indicated by a two-dot chain line, and the internal structure of the housing 6 is indicated by a solid line. A loading port 61 for loading the substrate 9 into the interior of the housing 6 is provided on the housing 6, and the loading port 61 can be opened and closed by a shutter 62. The loading port 61 is provided, for example, at a position on the (-Y) side of the upper surface of the housing 6. In Figure 1 the example shown, the loading port 61 is located vertically above the stage 21 disposed at the loading position described later.

[0057] The loading and unloading of the substrate 9 to and from the drawing apparatus 1 via the loading port 61 is, for example, performed by a loading apparatus 95 that adsorbs and holds the upper surface of the substrate 9 (see Figure 7B)This can be carried out by the loading and unloading device 95. Alternatively, the loading and unloading of the substrate 9 to and from the drawing device 1 can also be carried out manually by an operator. That is, when loading the substrate 9 into the drawing device 1, either the automatic loading by the loading device 95 or the manual loading by the operator is selectively carried out. The same applies to the case of unloading the substrate 9 from the drawing device 1.

[0058] The stage 21 is a substantially rectangular flat plate-shaped member disposed below (i.e., on the (-Z) side) the alignment unit 3 and the drawing unit 4. The stage 21 has a substrate holding portion 25 that holds the substrate 9 in a horizontal state from below. The substrate holding portion 25 is, for example, a vacuum chuck that adsorbs and holds the lower surface of the substrate 9. The substrate holding portion 25 may have a structure other than a vacuum chuck, for example, it may be a mechanical chuck. The upper surface 91 of the substrate 9 placed on the substrate holding portion 25 is substantially perpendicular to the Z direction and substantially parallel to the X direction and the Y direction.

[0059] The stage moving mechanism 22 is a moving mechanism that relatively moves the stage 21 with respect to the alignment unit 3 and the drawing unit 4 in the horizontal direction (i.e., a direction substantially parallel to the upper surface 91 of the substrate 9). The stage moving mechanism 22 has a first moving mechanism 23 and a second moving mechanism 24. The second moving mechanism 24 linearly moves the stage 21 in the X direction along the guide rail. The first moving mechanism 23 linearly moves the stage 21 together with the second moving mechanism 24 in the Y direction along the guide rail. The drive sources of the first moving mechanism 23 and the second moving mechanism 24 are, for example, linear servo motors or drive sources with motors mounted on ball screws. The structures of the first moving mechanism 23 and the second moving mechanism 24 can be variously changed.

[0060] In the drawing device 1, a stage rotation mechanism that rotates the stage 21 around a rotation axis extending in the Z direction may also be provided. In addition, a stage lifting mechanism that moves the stage 21 in the Z direction may be provided in the drawing device 1. As the stage rotation mechanism, for example, a servo motor can be used. As the stage lifting mechanism, for example, a linear servo motor can be used. The structures of the stage rotation mechanism and the stage lifting mechanism can be variously changed.

[0061] The alignment unit 3 has a plurality of (two in the example shown) alignment cameras 31 arranged in the X direction. Figure 1 Each alignment camera 31 is supported above the stage 21 and the stage moving mechanism 22 by a support portion 40 provided across the stage 21 and the stage moving mechanism 22. The support portion 40 is a single member provided at one position in the Y direction. Figure 1 In the example shown, the support portion 40 is a gantry-shaped member (so-called gantry) that spans the stage 21 and the stage moving mechanism 22.

[0062] In Figure 1 In the example shown in Figure 1 , two alignment cameras 31 are mounted on the side surface of the support portion 40 on the (+Y) side. For example, one of the two alignment cameras 31 is fixed to the support portion 40, and the other alignment camera 31 can move in the X direction on the support portion 40. Thereby, the distance in the X direction between the two alignment cameras 31 can be changed. It should be noted that the number of alignment cameras 31 of the alignment unit 3 can be one or three or more.

[0063] Each alignment camera 31 has an imaging element and an optical system (not shown). Each alignment camera 31 is, for example, an area camera that acquires a two-dimensional image. In each alignment camera 31, the reflected light of the illumination light introduced from an illumination light source (not shown) to the upper surface 91 of the substrate 9 is guided to the imaging element via the optical system. The imaging element receives the reflected light from the upper surface 91 of the substrate 9 and acquires an image of a substantially rectangular imaging area. The alignment camera 31 images alignment marks (not shown) preset on the upper surface 91 of the substrate 9. As the above-mentioned illumination light source, various light sources such as LEDs (Light Emitting Diodes) can be used. It should be noted that the alignment camera 31 can also be other types of cameras such as line cameras.

[0064] The image (hereinafter, also referred to as "alignment image") including the alignment marks acquired by the alignment camera 31 is sent to Figure 1 the control unit 8 shown in Figure 1 . In the control unit 8, alignment of the substrate 9 (that is, correction of the relative position of the substrate 9 with respect to the drawing head 41 described later) is performed based on the alignment image.

[0065] The drawing unit 4 has a plurality of (six in the example shown in Figure 1 ) drawing heads 41 arranged in the X direction. The plurality of drawing heads 41 have substantially the same structure. Each drawing head 41 has a spatial light modulator that irradiates the modulated (i.e., spatially modulated) light downward. Each drawing head 41 is supported by the above-mentioned support portion 40 above the stage 21 and the stage moving mechanism 22. In Figure 1 the example shown in Figure 1 , six drawing heads 41 are mounted on the side surface of the support portion 40 on the (-Y) side. In other words, in the Y direction, the six drawing heads 41 are arranged on the opposite side of the support portion 40 from the above-mentioned two alignment cameras 31. In other words, in the Y direction, the two alignment cameras 31 are located on the opposite side of the six drawing heads 41 from the substrate holding portion 25 of the stage 21 located at the loading position described later.

[0066]

[0066] In Figure 1In the example shown, six drawing heads 41 are arranged in a substantially linear manner substantially parallel to the X direction. In addition, the distance in the Z direction between the six drawing heads 41 and the upper surface 91 of the substrate 9 on the stage 21 is substantially the same. In other words, the arrangement direction of the six drawing heads 41 is substantially parallel to the upper surface 91 of the substrate 9 and substantially perpendicular to the Y direction. In other words, the positions of the six drawing heads 41 in the Y direction and the Z direction are substantially the same.

[0067] It should be noted that the arrangement direction of the above-described drawing heads 41 only needs to be a direction inclined with respect to the Y direction, and does not necessarily have to be parallel to the X direction. In the drawing unit 4, a plurality of drawing heads 41 do not necessarily have to be arranged in a straight line, and for example, they may be arranged in a grid pattern. In addition, in the drawing unit 4, the number of drawing heads 41 may be one or two or more.

[0068] In the drawing apparatus 1, pattern drawing of the substrate 9 is performed in a so-called multi-path manner. Specifically, while irradiating the upper surface 91 of the substrate 9 with modulated light from a plurality of drawing heads 41 of the drawing unit 4, the substrate 9 is moved in the Y direction by the first moving mechanism 23 of the stage moving mechanism 22 and passed under the drawing heads 41. As a result, the irradiation regions of the light from the plurality of drawing heads 41 are scanned in the Y direction on the substrate 9, and the substrate 9 is drawn. Next, the substrate 9 is stepwise moved a predetermined distance in the X direction by the second moving mechanism 24. Then, again, the substrate 9 is moved in the Y direction by the first moving mechanism 23 and light is irradiated from the drawing heads 41 to the substrate 9 in parallel with this movement, and the substrate 9 is drawn. In the drawing apparatus 1, the substrate 9 is pattern-drawn by alternately irradiating light to the substrate 9 moving in the Y direction and stepwise moving the substrate 9 in the X direction.

[0069] In the following description, the Y direction is referred to as the "main scanning direction", and the X direction is referred to as the "sub-scanning direction". The main scanning direction and the sub-scanning direction are directions substantially parallel to the upper surface 91 of the substrate 9. In the stage moving mechanism 22, the first moving mechanism 23 is a main scanning mechanism that relatively moves the stage 21 relative to the drawing heads 41 in the main scanning direction. In addition, the second moving mechanism 24 is a sub-scanning mechanism that relatively moves the stage 21 relative to the drawing heads 41 in the sub-scanning direction. It should be noted that in the drawing apparatus 1, the substrate 9 may also be drawn by a single-path method (also referred to as a single-path method) in which the substrate 9 is relatively moved only once in the Y direction with respect to the drawing heads 41 to complete the pattern drawing on the substrate 9. In this case, during pattern drawing, the sub-scanning of the substrate 9 (i.e., the stepwise movement in the X direction) by the second moving mechanism 24 is not performed.

[0070] The calibration unit 5 is provided on the (+Y) side of the substrate holding unit 25 on the stage 21. The calibration unit 5 is used for calibrating the drawing head 41 (i.e., for measuring and correcting the irradiation position of the light from the drawing head 41).

[0071] Figure 2 is a top view showing an enlarged view of the vicinity of the calibration unit 5 of the drawing device 1. Figure 3 is a front view showing the structure of the calibration unit 5 and the drawing head 41. In Figure 3 the state where the drawing head 41 is vertically above the calibration unit 5 is shown. In Figure 3 the internal structure of the stage 21 and the internal structure of one drawing head 41 are shown. The structures of the other drawing heads 41 are substantially the same as that of this one drawing head 41.

[0072] As Figure 3 shown, the drawing head 41 includes a light source unit 42, an illumination optical system 43, a spatial light modulator 44 (hereinafter, also simply referred to as "light modulator 44"), and a projection optical system 45. The light emitted from the light source unit 42 is guided by the illumination optical system 43 to the light modulator 44, and after being modulated by the light modulator 44, it is guided by the projection optical system 45 to below the drawing head 41 (i.e., in the (-Z) direction).

[0073] The light source unit 42 has a plurality of light sources that emit lights of different wavelengths. In Figure 3 the example shown, the light source unit 42 has three light sources 421 to 423. As the light sources 421 to 423, various light sources such as LD (Laser Diode) can be used. When drawing a pattern on the substrate 9, according to the type of the photosensitive material on the substrate 9, etc., for example, two or more of the light sources 421 to 423 are used. It should be noted that the number of light sources provided in the light source unit 42 can be one or two, or four or more. The light sources provided in the light source unit 42 are not limited to LD, and various types of light sources can be used.

[0074] The illumination optical system 43 and the projection optical system 45 each have a plurality of optical elements such as lenses (not shown). As the light modulator 44, various light modulators such as DMD (Digital Micro Mirror Device), GLV (Grating Light Valve) (registered trademark of Silicon Light Machines (Sunnyvale, California)) can be used. The light modulator 44 is not limited to the above example, and various types of light modulators can be used.

[0075] The calibration unit 5 includes a photographing unit 51 and a scale unit 52. The scale unit 52 is a substantially flat plate-shaped member provided on the stage 21. The scale unit 52 is disposed on the upper surface of the stage 21 and is adjacent to the (+Y) side of the substrate holding unit 25 (i.e., disposed close thereto). Figure 2 In the example shown, the scale unit 52 is a substantially rectangular belt-shaped member extending substantially parallel to the X direction and has translucency. A plurality of scales indicating positions in the X direction on the main surface are provided on the main surface on the (+Z) side of the scale unit 52. In other words, the scale unit 52 is a translucent scale member, for example, a substantially transparent glass scale. The scales of the scale unit 52 are, for example, cross patterns or patterns of other shapes. It should be noted that the scale unit 52 may also be a translucent member.

[0076] The photographing unit 51 is installed inside the stage 21 below the scale unit 52. The photographing unit 51 includes a calibration camera 53 and a camera moving mechanism 54. The calibration camera 53 is disposed vertically below the scale unit 52 and faces upward. The calibration camera 53 is, for example, a digital camera having a CCD (Charged Coupled Devices) or a CMOS (Complementary Metal Oxide Semiconductor) as a photographing element. It should be noted that the type and performance of the calibration camera 53 can be appropriately set.

[0077] Low-reflection processing is performed on the upper end portion of the calibration camera 53 (i.e., the portion facing the drawing head 41 with the scale unit 52 therebetween). Specifically, for example, an antireflection film for reducing the reflectance is pasted on the frame of the objective lens of the calibration camera 53. Thereby, when photographing is performed using the alignment camera 31, it is possible to suppress the unintended photographing of reflected light from the calibration camera 53. It should be noted that the above low-reflection processing can be performed by various structures and methods other than the antireflection film.

[0078] The camera moving mechanism 54 is a moving mechanism that linearly moves the calibration camera 53 along a guide rail in the X direction (i.e., a direction substantially parallel to the arrangement direction of the plurality of drawing heads 41) inside the stage 21. The drive source of the camera moving mechanism 54 is, for example, a linear servo motor or a drive source in which a motor is mounted on a ball screw. The structure of the camera moving mechanism 54 can be variously changed.

[0079] In the drawing apparatus 1, with a plurality of drawing heads 41 positioned vertically above the scale portion 52 of the calibration unit 5, the calibration camera 53 is moved by the camera moving mechanism 54 and is disposed in a stationary state vertically below one of the drawing heads 41 to be calibrated. A prescribed calibration pattern (i.e., a pattern for calibrating the drawing head 41) is emitted from this one drawing head 41 toward the scale portion 52. The calibration pattern is, for example, a cross-shaped pattern. The shape of the calibration pattern may be any shape as long as the centroid position can be calculated, and various modifications can be made.

[0080] The calibration camera 53 captures, from below through the scale portion 52, the irradiation area of the light from the drawing head 41 on the scale portion 52 (i.e., the calibration pattern) together with the above-described scale pre-formed on the scale portion 52. In other words, the calibration camera 53 captures the calibration pattern that has passed through the scale portion 52 together with the scale. The image acquired by the calibration camera 53 (hereinafter, also referred to as the "detection image") is sent to Figure 1 the control unit 8 shown in the figure. In the drawing apparatus 1, for one drawing head 41, a plurality of detection images are acquired by the calibration camera 53, and the plurality of detection images are sent to the control unit 8. In the control unit 8, calibration of the above-described one drawing head 41 is performed based on the plurality of detection images.

[0081] In the drawing apparatus 1, when calibrating other drawing heads 41, the calibration camera 53 is moved in the X direction by the camera moving mechanism 54 and stopped vertically below the other drawing head 41. Then, calibration of the other drawing heads 41 is performed in the same steps as described above.

[0082] Figure 4 FIG. shows the configuration of a computer 800 that functions as the control unit 8. The computer 800 has a configuration of a general computer system including a CPU (Central Processing Unit) 81, a ROM (Read-Only Memory) 82, a RAM (Random Access Memory) 83, a fixed disk 84, a display 85, an input unit 86, a reading device 87, a communication unit 88, a GPU (Graphics Processing Unit) 89, and a bus 80. The CPU 81 performs various arithmetic processes. The GPU 89 performs various arithmetic processes related to image processing. The ROM 82 stores basic programs. The RAM 83 stores various information. The fixed disk 84 stores information. The display 85 is a display unit that displays various information such as images.

[0083] The input unit 86 includes a keyboard 86a and a mouse 86b that receive inputs from the operator. The reading device 87 reads information from a computer-readable recording medium 871 such as an optical disc, a magnetic disk, an optical magnetic disk, or a memory card. The display 85, the keyboard 86a, the mouse 86b, and the reading device 87 are connected to the bus 80 via an interface I / F. The communication unit 88 transmits and receives signals to and from external devices such as the computer 800. The bus 80 is a signal circuit that connects the CPU 81, the GPU 89, the ROM 82, the RAM 83, the fixed disk 84, the display 85, the input unit 86, the reading device 87, and the communication unit 88.

[0084] In the computer 800, the program 872 is previously read from the recording medium 871 via the reading device 87 and stored in the fixed disk 84. The program 872 may also be stored in the fixed disk 84 via a network. The CPU 81 and the GPU 89 utilize the RAM 83 and the fixed disk 84 and execute arithmetic processing according to the calibration program 872. The CPU 81 and the GPU 89 function as an arithmetic unit in the computer 800. In addition to the CPU 81 and the GPU 89, other configurations may also function as an arithmetic unit.

[0085] Figure 5 It represents Figure 4 a block diagram of the functions of the control unit 8 implemented by the computer 800 shown. The configurations other than the control unit 8 are also shown together in Figure 5 . The control unit 8 includes a storage unit 801, a shooting control unit 802, an evaluation value acquisition unit 803, a calibration image group setting unit 804, a calibration information acquisition unit 805, an alignment information acquisition unit 806, and a drawing control unit 807. The evaluation value acquisition unit 803 includes a position detection unit 808 and an evaluation value calculation unit 809. The storage unit 801 is implemented using the RAM 83 and the fixed disk 84, etc. The shooting control unit 802, the evaluation value acquisition unit 803, the calibration image group setting unit 804, the calibration information acquisition unit 805, the alignment information acquisition unit 806, the drawing control unit 807, the position detection unit 808, and the evaluation value calculation unit 809 are implemented by the CPU 81, the GPU 89, the ROM 82, the RAM 83, the fixed disk 84, and their peripheral configurations.

[0086] The storage unit 801 stores various information such as predetermined pattern data (i.e., drawing data) drawn on the substrate 9 and information related to the calibration of the drawing head 41 in advance. The shooting control unit 802 controls the drawing head 41 and the calibration camera 53 to irradiate the calibration pattern pre-stored in the storage unit 801 from the drawing head 41 onto the scale unit 52 (refer to Figure 2 and Figure 3) The inspection images for calibration are acquired by the calibration camera 53. The inspection images include the images of the scale portion 52 and the calibration pattern. In the drawing device 1, a plurality of inspection images are acquired for one drawing head 41. The plurality of inspection images are sent from the calibration camera 53 to the control unit 8 and stored in the storage unit 801.

[0087] The evaluation value acquisition unit 803 obtains a variation evaluation value for a set of inspection images (i.e., an inspection image group) having a specified number (an integer of 2 or more) of inspection images included in the plurality of inspection images. Specifically, the position detection unit 808 of the evaluation value acquisition unit 803 obtains the position of the calibration pattern in each inspection image of the inspection image group (hereinafter, also referred to as "pattern position"). In other words, the position detection unit 808 obtains the irradiation position of the light from the drawing head 41 on the scale portion 52 in each inspection image. As described above, since the scale portion 52 is fixed to the stage 21, the relative position of the scale portion 52 with respect to the substrate holding portion 25 is also fixed. Therefore, by detecting the irradiation positions of the calibration pattern on the plurality of scales of the scale portion 52, the relative position of the irradiation position of the light irradiated from the drawing head 41 with respect to the substrate holding portion 25 is obtained.

[0088] The evaluation value calculation unit 809 of the evaluation value acquisition unit 803 obtains a variation evaluation value based on the pattern positions in the specified number of inspection images of the inspection image group obtained by the position detection unit 808. The variation evaluation value is a parameter indicating the magnitude of the deviation of the pattern positions corresponding to the specified number of inspection images. If the deviation of the pattern positions in the inspection image group becomes larger, the variation evaluation value also becomes larger, and if the deviation becomes smaller, the variation evaluation value also becomes smaller.

[0089] The calibration image group setting unit 804 determines whether to use the inspection image group as a calibration image group for calibration based on the variation evaluation value obtained by the evaluation value acquisition unit 803. Specifically, when the variation evaluation value is equal to or less than a specified threshold value, the calibration image group setting unit 804 determines that the deviation of the pattern positions in the inspection image group is within an allowable range, and sets the inspection image group as the calibration image group. On the other hand, when the variation evaluation value is greater than the above threshold value, the calibration image group setting unit 804 determines that the deviation of the pattern positions in the inspection image group is greater than an allowable degree. In this case, as described later, a new inspection image group is selected, and based on the variation evaluation value of the new inspection image group, the calibration image group setting unit 804 determines whether to use the new inspection image group as the calibration image group.

[0090] The calibration information acquisition unit 805 acquires calibration information for calibrating the drawing head 41 (i.e., correcting the irradiation position of the light from the drawing head 41 on the substrate) based on the pattern positions of the respective inspection images of the calibration image group set by the calibration image group setting unit 804.

[0091] The alignment information acquisition unit 806 acquires alignment information used in the alignment of the substrate 9 (i.e., correction of the relative position of the substrate 9 with respect to the drawing head 41) based on the image of the alignment mark acquired by the alignment camera 31 of the alignment unit 3 (hereinafter, also referred to as "alignment image"). Specifically, based on the position of the alignment mark in the alignment image, the position of the substrate 9 on the substrate holding unit 25 is obtained, and the deviation amount of the substrate 9 on the substrate holding unit 25 from the design position is obtained. In other words, the deviation amount of the relative position of the substrate 9 with respect to the drawing head 41 from the design position is obtained. Based on this deviation amount, the alignment information acquisition unit 806 obtains the above alignment information for correcting so that the relative position of the substrate 9 with respect to the drawing head 41 coincides with the design position. This alignment information is, for example, information for correcting the movement of the substrate 9 caused by the stage moving mechanism 22 when patterning the substrate 9. Alternatively, this alignment information may also be information for correcting the drawing data of the pattern drawn on the substrate 9 according to the above deviation amount.

[0092] The drawing control unit 807 controls the plurality of drawing heads 41 and the stage moving mechanism 22 based on the drawing data stored in the storage unit 801, the correction information of each drawing head 41 obtained by the correction information acquisition unit 805, the alignment information obtained by the alignment information acquisition unit 806, etc., so that the substrate 9 moves relatively with respect to the plurality of drawing heads 41, and the plurality of drawing heads 41 perform drawing on the substrate 9.

[0093] Next, refer to Figure 6 and Figures 7A - 7H The pattern drawing performed by the drawing device 1 will be described. Figure 6 is a diagram showing an example of the flow of pattern drawing on the substrate 9. To explain the operation of the drawing device 1, Figures 7A - 7H is a front view schematically showing the main structure of the drawing device 1. In Figures 7A - 7H the internal structure of the stage 21 is shown by a solid line.

[0094] When drawing on the substrate 9, first, the stage 21 is arranged in a stationary state at the Figure 7A position shown. In the following description, the Y-direction position of the stage 21 shown in Figure 7A is referred to as the "loading position". In the state where the stage 21 is at this loading position, the substrate holding unit 25 is located lower than the one mounted on the support part 40 (refer to Figure 1) A plurality of drawing heads 41 and a plurality of alignment cameras 31 are located on the (-Y) side. In addition, as described above, the loading port 61 of the housing 6 is located vertically above the substrate holding portion 25 of the stage 21 in the loading position. The loading port 61 is closed by a shutter 62. A substrate 9 on which drawing in the drawing device 1 has been completed is held on the substrate holding portion 25.

[0095] Next, as Figure 7B shown, by moving the shutter 62, the loading port 61 is opened, and the drawn substrate 9 is automatically unloaded by the loading device 95. The loading device 95 holds, for example, the upper surface of the drawn substrate 9 (i.e., the main surface on the (+Z) side). The loading device 95 moves the held substrate 9 upward and unloads it to the outside of the housing 6 via the loading port 61.

[0096] When the unloading of the drawn substrate 9 is completed, as Figure 7C shown, the loading device 95 adsorbs and holds an undrawn substrate 9 (i.e., the substrate 9 to be drawn by the drawing device 1), and loads it into the housing 6 via the loading port 61. The undrawn substrate 9 is placed on the substrate holding portion 25 of the stage 21 and held by the substrate holding portion 25. After that, the loading device 95 retracts to the outside of the drawing device 1, and as Figure 7D shown, the loading port 61 is closed by the shutter 62. Thus, the loading and unloading process of the substrate 9 is completed.

[0097] This loading and unloading process is an operation related to the unloading and loading of the substrate 9 performed by the shutter 62 between opening and closing the loading port 61. The time required for this loading and unloading process (i.e., the time from opening the loading port 61 to closing the loading port 61, hereinafter also referred to as the "loading and unloading time") is, for example, about 6 seconds. The loading and unloading time is the time required to unload one substrate 9 from the substrate holding portion 25 and load a new substrate 9 into the substrate holding portion 25. It should be noted that when the unloading and loading of the substrate 9 to the drawing device 1 are performed manually by an operator, the loading and unloading time is usually longer than the loading and unloading time performed by the loading device 95. For example, the loading and unloading time performed manually by an operator is about 15 seconds.

[0098] In the drawing device 1, in the state where the stage 21 is in the Figures 7A - 7D shown loading position, the scale portion 52 of the calibration unit 5 is located vertically below the drawing head 41. In the following description, Figures 7A - 7DThe position of the scale unit 52 in the Y direction shown is referred to as the "calibration position". In the drawing device 1, in a state where the stage 21 is at the loading position and the scale unit 52 is at the calibration position, calibration of a plurality of drawing heads 41 is sequentially performed in parallel with the loading and unloading processes of the substrate 9 (step S11). Thus, correction information for correcting the irradiation position of the light from each drawing head 41 is obtained. Calibration of the plurality of drawing heads 41 is completed, for example, within the above-described loading and unloading time (that is, between opening the loading port 61 and closing the loading port 61). Details of the calibration of the drawing head 41 will be described later.

[0099] When step S11 (that is, loading and unloading of the substrate 9 and calibration of the plurality of drawing heads 41) ends, the first moving mechanism 23 of the stage moving mechanism 22 moves the stage 21 in the (+Y) direction. As Figure 7E shown, the stage 21 moves below the alignment camera 31 and stops at the Figure 7F shown standby position. As Figure 7E shown, when the stage 21 passes below the alignment camera 31, the alignment camera 31 captures an alignment mark (not shown) of the substrate 9 preset on the substrate holding portion 25. When capturing the alignment mark, pulsed illumination light (i.e., a flash) is irradiated from the illumination light source of the alignment unit 3 to the imaging area of the alignment camera 31. Thus, the alignment mark on the moving substrate 9 is captured with high precision. As described above, in the calibration unit 5 passing below the alignment camera 31, since low-reflection processing is performed on the upper end portion of the calibration camera 53, it is possible to suppress or prevent reflected light generated by the above-described illumination light due to the calibration camera 53 from entering the alignment camera 31.

[0100] The image (i.e., the alignment image) including the alignment mark obtained by the alignment camera 31 is sent to the control unit 8 and stored in the storage unit 801 (see Figure 5 ). In the alignment information acquisition unit 806, alignment information is obtained based on this alignment image. Then, based on this alignment information, the alignment process of the substrate 9 is performed by the drawing control unit 807 (step S12). In the alignment process, in order to make the position of the substrate 9 coincide with a specified design position, for example, displacement (i.e., movement of a minute distance) in the X direction and Y direction of the stage 21, rotation, or correction of the drawing data of the pattern drawn on the substrate 9 is performed.

[0101] When the above alignment process ends, the stage 21 located at the standby position starts to move in the (-Y) direction. In the calibration unit 5, before the stage 21 starts to move in the (-Y) direction, the calibration camera 53 moves in the X direction and retracts from the retracted position on the (+X) side or (-X) side in the vertical direction of the scale unit 52. That is, the retracted position is a position on the stage 21 that is on the (+X) side or (-X) side of the position where the scale unit 52 is provided. Thereby, it is possible to suppress or prevent the high-intensity light used in the pattern drawing from entering the calibration camera 53.

[0102] In the drawing device 1, as Figure 7G shown, the substrate 9 held by the substrate holding unit 25 passes under the drawing head 41. Then, by the drawing control unit 807 (refer to Figure 5 ), controlling each drawing head 41 and the stage moving mechanism 22 based on the above drawing data and correction information, etc., modulated light is irradiated from the plurality of drawing heads 41 onto the substrate 9 on the stage 21 moving in the Y direction under the plurality of drawing heads 41 to draw a pattern (step S13).

[0103] In the present embodiment, as described above, since the pattern drawing of the substrate 9 is performed in a multi-path manner, the pattern is drawn by irradiating the modulated light from the drawing head 41 onto the substrate 9 reciprocating in the Y direction under the drawing head 41. In addition, when drawing a pattern on the substrate 9, in each drawing head 41, it is preferable to use two or more of the three light sources 421 to 423 of the light source unit 42 (refer to Figure 3 ). Thereby, it is possible to perform appropriate pattern drawing according to the type of photosensitive material on the substrate 9, etc.

[0104] When the drawing of the pattern on the substrate 9 ends, the stage 21 moves to the Figure 7H shown loading position (step S14). At this time, the calibration camera 53 moves in the X direction from the retracted position and returns to the vertical below the scale unit 52. Thus, the drawing of the pattern on one substrate 9 ends.

[0105] In the actual drawing device 1, returning from step S14 to step S11, steps S11 to S14 are sequentially performed on a plurality of substrates 9 to draw patterns. In the drawing device 1, in this way, each time a substrate 9 is loaded into the substrate holding unit 25 (step S11), each drawing head 41 is calibrated. Even when continuously drawing patterns on a plurality of substrates 9, it is possible to maintain the accuracy of the pattern drawing on the substrate 9 at a high level. In addition, since the calibration of the drawing heads 41 is performed in parallel with the loading and unloading of the substrate 9, it is possible to shorten the time required for the drawing process of the plurality of substrates 9. In other words, in the drawing device 1, it is possible to suppress an increase in the cycle time and perform the calibration of the drawing heads 41.

[0106] Next, with reference to Figure 8 and Figure 9 , the details of the calibration of the drawing head 41 will be described. Figure 8 is a diagram showing the process of calibration based on the first calibration method. Figure 9 is a diagram showing the process of calibration based on the second calibration method. In Figure 8 and Figure 9 , the calibration processes of one drawing head 41 are respectively shown. The calibration processes of the other drawing heads 41 are the same as those shown in Figure 8 and Figure 9 . Hereinafter, first, the first calibration method will be described, and then the second calibration method will be described.

[0107] When calibrating the drawing head 41 using the first calibration method, first, with the scale unit 52 in the calibration position, the calibration camera 53 of the photographing unit 51 is moved in the X direction by the camera moving mechanism 54 (refer to Figure 2 and Figure 3 ). The calibration camera 53 is disposed vertically below one drawing head 41 to be calibrated.

[0108] Then, the calibration camera 53 is stationary vertically below the drawing head 41, and by controlling the light source unit 42 and the light modulator 44 of the drawing head 41 by the photographing control unit 802 (refer to Figure 3 ), etc., the calibration pattern is irradiated from the drawing head 41 to the scale unit 52. In the light source unit 42, when irradiating the calibration pattern, only a predetermined one of the light sources 421 to 423 (refer to Figure 3 ) is used. Thereby, the calibration pattern on the scale unit 52 is formed by light of a single wavelength.

[0109] Next, the calibration camera 53 is controlled by the photographing control unit 802 (refer to Figure 5 ), whereby the calibration pattern irradiated onto the scale unit 52 in the calibration position and the scale of the scale unit 52 are photographed together, and a detection image is acquired. The calibration camera 53 photographs the calibration pattern irradiated by one drawing head 41 a plurality of times, and acquires a plurality of detection images (step S21). Each of the plurality of detection images includes an image of the scale unit 52 and the calibration pattern. The plurality of detection images are sent to the control unit 8 and stored in the storage unit 801 (refer to Figure 5 ). The number of detection images acquired in step S21 is, for example, five. The number of the detection images only needs to be equal to or more than the number of detection images included in the detection image group selected in the subsequent step S22, and various changes can be made within the range of two or more.

[0110] Next, the evaluation value acquisition unit 803 (refer to Figure 5 ) selects, from the plurality of detected images, a set of detected images that is a set of a prescribed number of two or more detected images. The prescribed number may be equal to or less than the number of detected images acquired in step S21, and various changes can be made within the range of two or more. In the present embodiment, all five detected images continuously acquired for one drawing device 1 are selected as the set of detected images. In other words, the prescribed number is the same as the number of detected images included in the set of detected images, which is five. Then, the position detection unit 808 (refer to Figure 5 ) obtains the position of the calibration pattern, that is, the pattern position, in each detected image of the set of detected images (step S22). The pattern position is obtained using various known image processing methods (such as pattern matching). The prescribed number of pattern positions corresponding to the prescribed number of detected images (five pattern positions in the present embodiment) is sent from the position detection unit 808 to the evaluation value calculation unit 809 (refer to Figure 5 ).

[0111] In the evaluation value calculation unit 809, a parameter representing the magnitude of the deviation of the prescribed number of pattern positions in the set of detected images, that is, the variation evaluation value, is obtained based on the prescribed number of pattern positions obtained by the position detection unit 808 (step S23). As described above, the variation evaluation value increases as the deviation of the pattern positions in the set of detected images increases, and decreases as the deviation decreases. The variation evaluation value is, for example, the standard deviation or variance of the prescribed number of pattern positions. It should be noted that the variation evaluation value is not limited to the standard deviation and variance, and may also be other parameters representing the magnitude (i.e., the degree of deviation) of the deviation of the prescribed number of pattern positions. The variation evaluation value obtained by the evaluation value calculation unit 809 is sent to the calibration image set setting unit 804 (refer to Figure 5 ).

[0112] In the calibration image set setting unit 804, the above variation evaluation value is compared with a prescribed threshold value previously stored in the storage unit 801 (step S24). Then, when the variation evaluation value is equal to or less than the threshold value, it is determined that the deviation of the pattern positions in the set of detected images is within the allowable range, and the set of detected images is set as the calibration image set suitable for calibrating the drawing head 41 (step S25).

[0113] This threshold value is determined in advance, for example, based on the resolution of the calibration camera 53, etc., and is stored in the storage unit 801 in advance. In the present embodiment, this threshold value is determined based on the following criteria. For example, when the resolution of the calibration camera 53 is 1 μm and the calibration of the drawing head 41 is performed with an accuracy of 1 μm or less, if the deviation of the pattern position in the detection image group is about 1 μm, it is determined that the jitter is caused by the above resolution, and this detection image group is suitable (i.e., can be used) as the correction image group. On the other hand, when this deviation is larger than 1 μm to a certain extent, it is highly likely that this deviation is caused by other reasons (for example, interference such as vibration of the stage 21), and therefore it is determined that this detection image group is not suitable as the correction image group.

[0114] In step S24, when the above variation evaluation value is greater than the threshold value, it is determined that the deviation of the pattern position in the detection image group is outside the allowable range, and it is determined that this detection image group is not suitable as the correction image group. The deviation of the pattern position in the case where the variation evaluation value is greater than the threshold value typically results from the vibration of the stage 21 when the substrate 9 loaded into the drawing apparatus 1 is placed on the substrate holding portion 25. In other words, this deviation of the pattern position results from the vibration of the stage 21 generated when the substrate 9 is loaded into the substrate holding portion 25 by the loading apparatus 95. That is, if the shooting timing of one or more detection images included in the detection image group overlaps with the time generated by this vibration of the stage 21, the above pattern position deviates significantly, and the possibility that the variation evaluation value is greater than the threshold value becomes high. This vibration of the stage 21 is, for example, larger in the moving direction of the first moving mechanism 23 using a linear servo motor, i.e., the Y direction. This vibration of the stage 21, for example, lasts for a short time of 0.5 seconds or less and then disappears.

[0115] In the drawing apparatus 1, in step S24, when it is determined that the variation evaluation value is greater than the threshold value, the control unit 8 confirms whether the number of times that the variation evaluation value is determined to be greater than the threshold value (hereinafter, also referred to as "the number of non - conforming times (NG times)") is equal to or less than a specified limit number (step S241). This limit number is an integer of one or more, and in the present embodiment, it is two. The limit number can be variously changed.

[0116] When the number of non - conforming times is equal to or less than the limit number, before the elapse of a specified standby time stored in the storage unit 801 in advance, the photographing unit 51 does not drive and stands by (step S242). This standby time is measured from the end of the shooting of the plurality of detection images in step S21. This standby time is preferably longer than or equal to the duration of the above vibration of the stage 21 (hereinafter, also referred to as "vibration duration"), and more preferably longer than the vibration duration. On the other hand, from the viewpoint of shortening the time required for calibration, it is not preferable for this standby time to be too long. In the present embodiment, this standby time is 0.5 seconds.

[0117] When this standby time has elapsed, the process returns to step S21, and the calibration camera 53 takes pictures of the calibration pattern corresponding to the above-described one drawing head 41 a plurality of times again, and a new plurality of detection images are acquired (step S21). The new plurality of (for example, five) detection images are sent to the control unit 8 and stored in the storage unit 801.

[0118] Next, in the same manner as described above, the evaluation value acquisition unit 803 selects a new detection image group that is a set of the above-described specified number (for example, five) of detection images from the new plurality of detection images. Then, the position detection unit 808 obtains the pattern position that is the position of the calibration pattern in each detection image of this new detection image group (step S22). Next, the evaluation value calculation unit 809 obtains a parameter, that is, a variation evaluation value, which represents the magnitude of the deviation of the above-described specified number (for example, five) of pattern positions in this new detection image group, based on the above-described specified number (for example, five) of pattern positions obtained in step S22 (step S23).

[0119] Then, the correction image group setting unit 804 compares the variation evaluation value with the above-described threshold value (step S24). When the variation evaluation value is equal to or less than the threshold value, this detection image group is set as the correction image group (step S25). When the variation evaluation value is greater than the threshold value, the number of non-conforming times is confirmed (step S241). Moreover, when the number of non-conforming times is equal to or less than the limit number of times (for example, two or less), in the same manner as described above, after the standby time has elapsed (step S242), steps S21 to S24 are repeated.

[0120] On the other hand, when the number of non-conforming times is greater than the limit number of times (for example, three or more), the calibration for one drawing head 41 during calibration is aborted (step S29). In other words, when a suitable detection image group cannot be obtained even if steps S21 to S24 are repeated for one drawing head 41 one more time than the limit number of times (three times in this embodiment), the calibration for this one drawing head 41 is aborted. In this embodiment, the time required for steps S21 to S24 (that is, the time from the start of shooting a plurality of detection images to the end of the comparison between the variation evaluation value and the threshold value) is several milliseconds to several tens of milliseconds, and the standby time in step S242 is 0.5 seconds as described above. Therefore, the time required to repeat steps S21 to S24 three times for one drawing head 41 is about 1 second.

[0121] For the drawing head 41 for which the calibration is aborted, for example, after the calibration of other drawing heads 41 is completed, the calibration is performed again. In step S29, the recalibration of the drawing head 41 for which the calibration is aborted is performed within the above-described loading / unloading time or after the loading / unloading process of the substrate 9 is completed and before the drawing on the substrate 9 starts.

[0122] When a calibration image group is set in step S25, based on the pattern positions in the above-specified number (e.g., five) of detection images included in the calibration image group, the calibration information acquisition unit 805 (refer to Figure 5 ) obtains calibration information for correcting the irradiation position of the light from the drawing head 41 (step S26).

[0123] Specifically, the arithmetic mean of the pattern positions in the above-specified number (e.g., five) of detection images included in the calibration image group is obtained, and this arithmetic mean is compared with the designed irradiation position (hereinafter, also referred to as the "designed position") on the scale portion 52 of the calibration pattern irradiated from the drawing head 41. Then, the distances in the X direction and Y direction (i.e., the deviation amounts from the designed position) between the arithmetic mean of the pattern positions and the designed position are obtained. Based on this deviation amount, the calibration information acquisition unit 805 obtains the above calibration information for correction in such a manner that the irradiation position of the light from the drawing head 41 coincides with the designed position. This calibration information is, for example, information for correcting the drawing data of the pattern drawn on the substrate 9 according to the above deviation amount. Alternatively, this calibration information may also be information for correcting the movement of the substrate 9 caused by the stage movement mechanism 22 when the pattern is drawn on the substrate 9.

[0124] In the drawing apparatus 1, when the acquisition of the calibration image group corresponding to one drawing head 41 (step S25) is completed, for example, in parallel with the acquisition of the calibration information corresponding to this one drawing head 41 (step S26), the calibration camera 53 is moved in the X direction by the camera movement mechanism 54. Alternatively, the movement of the calibration camera 53 in the X direction may also be performed after the acquisition of the calibration information corresponding to this one drawing head 41 (step S26) is completed. The calibration camera 53 is arranged in a stationary state vertically below another drawing head 41 adjacent to the above one drawing head 41 that has completed the acquisition of the calibration image group in the X direction.

[0125] The time required for the movement of the calibration camera 53 between two drawing heads 41 adjacent in the X direction (e.g., 0.8 seconds) is generally longer than the time required for the acquisition of the calibration information in step S26 (e.g., several milliseconds). Therefore, the acquisition of the calibration information in step S26 ends before the calibration camera 53 is arranged vertically below the above another drawing head 41.

[0126] When the calibration camera 53 is arranged vertically below this another drawing head 41, in the same manner as above, steps S21 to S26 are performed on this another drawing head 41 to obtain calibration information. In the drawing apparatus 1, steps S21 to 26 are sequentially performed on all the drawing heads 41 of the drawing unit 4, and the calibration information corresponding to each drawing head 41 is sequentially obtained.

[0127] In the drawing apparatus 1, as described above, by re - performing steps S21 to S24 (that is, obtaining a set of detection images, etc.) for one drawing head 41 that captures a detection image during the vibration of the stage 21 generated when the substrate 9 is loaded, calibration information is obtained with high precision. In addition, since the duration of the vibration of the stage 21 generated when the substrate 9 is loaded is 0.5 seconds and the movement time of the calibration camera 53 between adjacent drawing heads 41 is 0.8 seconds, for drawing heads 41 other than the above - mentioned one drawing head 41, the acquisition timing of the detection image does not overlap with the vibration of the stage 21. Therefore, for other drawing heads 41, without re - performing steps S21 to S24, calibration information can be obtained with high precision.

[0128] In the present embodiment, as described above, the time required for steps S21 to S24 in each drawing head 41 is several milliseconds to several tens of milliseconds. For one of the six drawing heads 41, the maximum time required for repeating steps S21 to S24 with an interval standby time is about 1 second. In addition, the movement time of the calibration camera 53 between adjacent drawing heads 41 is 0.8 seconds. Therefore, the time required to obtain calibration information for all six drawing heads 41 is about 5 seconds, which is less than the loading and unloading time of the substrate 9 (for example, about 6 seconds). Therefore, an increase in the cycle time caused by the calibration of the drawing heads 41 can be prevented or suppressed.

[0129] In the drawing apparatus 1, when obtaining a detection image of one drawing head 41, irradiation of the calibration pattern from other drawing heads 41 can be stopped, or the calibration pattern can be irradiated from other drawing heads 41 to the scale portion 52.

[0130] As described above, the loading and unloading of the substrate 9 with respect to the drawing apparatus 1 can be automatically performed by the loading apparatus 95 or manually operated by an operator. In other words, the loading of the substrate 9 with respect to the drawing apparatus 1 can be switched between automatic loading by the loading apparatus 95 and manual loading by the operator. The same applies to the unloading of the substrate 9 from the drawing apparatus 1. When the substrate 9 is manually loaded with respect to the drawing apparatus 1, the duration of the vibration of the stage 21 when the substrate 9 is placed on the substrate holding portion 25 may be different from the vibration duration (0.5 seconds) in the case of automatically loading the substrate 9.

[0131] In the drawing apparatus 1, the standby time in step S242 can be switched between a first standby time corresponding to the automatic loading of the substrate 9 and a second standby time corresponding to the manual loading of the substrate 9. The second standby time is a time different from the first standby time and is stored in advance in the storage unit 801 in the same manner as the first standby time. When the vibration duration of the stage 21 during the manual loading of the substrate 9 is longer than that during the automatic loading of the substrate 9, the second standby time is preferably set to be longer than the first standby time (e.g., 0.5 seconds). In addition, when the vibration duration of the stage 21 during the manual loading of the substrate 9 is shorter than that during the automatic loading of the substrate 9, the second standby time is preferably set to be shorter than the first standby time. The switching between the first standby time and the second standby time is achieved, for example, by a worker making a prescribed input via the input unit 86 of the control unit 8.

[0132] In the drawing apparatus 1, when acquiring the detection image of the drawing head 41, for example, when the variation evaluation value is greater than the threshold due to vibration of the stage 21 caused by reasons other than the loading of the substrate 9, similar to the case where the vibration is caused by the loading of the substrate 9, by re-performing steps S21 to S24, the correction information of the drawing head 41 can be obtained with high accuracy. In addition, when the variation evaluation value is greater than the threshold for two or more drawing heads 41, by re-performing steps S21 to S24 for each of the two or more drawing heads 41, the correction information of the two or more drawing heads 41 can be obtained with high accuracy.

[0133] In the drawing apparatus 1, if the correction image group for each drawing head 41 is set in the above step S11, the acquisition of the correction information of each drawing head 41 (step S26) can also be performed after the loading port 61 is closed and before starting to draw on the substrate 9. For example, the acquisition of the correction information of each drawing head 41 can also be performed during the movement of the substrate 9 and the stage 21 from Figures 7A - 7D the shown loading position to Figure 7F the shown standby position or during the standby of the substrate 9 and the stage 21 at this standby position until the start of drawing.

[0134] In the drawing apparatus 1, it is sufficient that the acquisition of the correction information for each drawing head 41 (step S11) and the alignment process of the substrate 9 (step S12) are completed before starting to draw the pattern on the substrate 9. In addition, the acquisition of the correction information for each drawing head 41 can be performed before or after the alignment process of the substrate 9, or can be performed almost in parallel.

[0135] Next, the second calibration method will be described. When calibrating the drawing head 41 by the second calibration method, first, in the same manner as in step S21, with the scale unit 52 in the calibration position, the calibration camera 53 is moved in the X direction and arranged vertically below one of the drawing heads 41 to be calibrated. Then, with the calibration camera 53 stationary vertically below the drawing head 41, a calibration pattern is irradiated from the drawing head 41 onto the scale unit 52.

[0136] Next, the calibration camera 53 captures the calibration pattern within a specified shooting time, and a plurality of detection images are obtained (step S31). The shooting time of the calibration pattern in step S31 is, for example, longer than the vibration duration (e.g., 0.5 seconds) of the stage 21 when the substrate 9 is loaded. In the present embodiment, the shooting time of the calibration pattern is 1 second, and a plurality of detection images are obtained during this 1 second. It should be noted that as long as the number of detection images obtained in step S31 is larger than the number of detection images included in the detection image group selected in step S32 described later, it can be determined in various ways.

[0137] Next, the evaluation value acquisition unit 803 (refer to Figure 5 ) selects a set of two or more specified numbers of detection images, that is, a detection image group, from the above plurality of detection images. In the present embodiment, among the plurality of detection images obtained in step S31, the first obtained detection image and the four detection images obtained immediately after that are selected as the detection image group. In other words, during the shooting time of the calibration pattern in step S31, five consecutive detection images obtained within several milliseconds to several tens of milliseconds from the acquisition of the first detection image are selected as the detection image group. Then, in substantially the same manner as in step S22, the position detection unit 808 obtains the position of the calibration pattern, that is, the pattern position, in each of the detection images of the detection image group (step S32). The specified number of pattern positions (five pattern positions in the present embodiment) corresponding to the above-specified number of detection images are sent from the position detection unit 808 to the evaluation value calculation unit 809.

[0138] Note that the specified number of detection images selected as the detection image group in step S32 is not necessarily the detection images captured near the start of step S31, and can be changed in various ways. For example, the last acquired detection image and four consecutive detection images acquired before this detection image can also be selected from the multiple detection images acquired in step S31 as the detection image group. In other words, the specified number of detection images selected as the detection image group can also be the detection images captured near the end of step S31. Or, five detection images continuously acquired near the center of the shooting time of the calibration pattern in step S31 can also be selected as the detection image group.

[0139] When step S32 ends, similar to step S23, the variation evaluation value is calculated by the evaluation value calculation unit 809 based on the specified number of pattern positions obtained by the position detection unit 808 (step S33). The variation evaluation value calculated by the evaluation value calculation unit 809 is sent to the calibration image group setting unit 804.

[0140] In the calibration image group setting unit 804, similar to step S24, the variation evaluation value is compared with the above threshold (step S34). Then, when the variation evaluation value is below the threshold, similar to step S25, the detection image group is set as the calibration image group suitable for calibrating the head 41 (step S35).

[0141] On the other hand, when the variation evaluation value is greater than the threshold, it is determined that the detection image group is not suitable as the calibration image group. As described above, typically, when the shooting timing of one or more detection images included in the detection image group overlaps with the vibration duration of the stage 21 when the substrate 9 is loaded, the possibility that the variation evaluation value is greater than the threshold is high.

[0142] In step S34, when the variation evaluation value is greater than the threshold, return to step S32, and a new detection image group is selected from the multiple detection images acquired in step S31. The new detection image group is a set of the specified number of detection images different from the specified number of detection images included in the above detection image group determined to be unsuitable in step S34. From the perspective of avoiding the above vibration duration of the stage 21, it is preferable that the shooting timing of the detection images included in the new detection image group is as far away as possible from the shooting timing of the detection images included in the above detection image group determined not to be suitable as the calibration image group. The new detection image group is, for example, five detection images captured near the end of step S31.

[0143] In the position detection unit 808, the pattern positions in each detection image of the new detection image group are obtained (step S32). Then, the new variation evaluation value is obtained by the evaluation value calculation unit 809 based on the pattern positions of a specified number in the new detection image group (step S33).

[0144] Then, the correction image group setting unit 804 compares the new variation evaluation value with the above threshold (step S34). When the new variation evaluation value is less than or equal to the threshold, the detection image group is set as the correction image group (step S35). When the variation evaluation value is greater than the threshold, the process returns to step S32 as described above, changes the detection image group, and repeats steps S32 to S34 until the correction image group is set.

[0145] When the correction image group is set in step S35, similar to step S26, based on the pattern positions in the above-specified number (for example, five) of detection images included in the correction image group, the correction information acquisition unit 805 obtains the correction information for correcting the irradiation position of the light from the drawing head 41 (step S36).

[0146] In the drawing device 1, when the acquisition of the correction image group corresponding to one drawing head 41 is completed (step S35), for example, in parallel with the acquisition of the correction information corresponding to this one drawing head 41 (step S36), the calibration camera 53 is moved in the X direction by the camera moving mechanism 54. Alternatively, the movement of the calibration camera 53 in the X direction may also be performed after the acquisition of the correction information corresponding to this one drawing head 41 (step S36). The calibration camera 53 is arranged in a stationary state vertically below another drawing head 41 adjacent to the above one drawing head 41 in the X direction after the acquisition of the correction image group.

[0147] The time required for the movement of the calibration camera 53 between two drawing heads 41 adjacent in the X direction (for example, 0.8 seconds) is generally longer than the time required for the acquisition of the correction information in step S36 (for example, several milliseconds). Therefore, the acquisition of the correction information in step S36 ends before the calibration camera 53 is arranged vertically below the above another drawing head 41.

[0148] When the calibration camera 53 is arranged vertically below this other drawing head 41, similar to the above, steps S31 to S36 are performed for this other drawing head 41 to obtain the correction information. In the drawing device 1, steps S31 to S36 are sequentially performed for all the drawing heads 41 of the drawing unit 4 to sequentially obtain the correction information corresponding to each drawing head 41.

[0149] In the drawing apparatus 1, as described above, by re-performing steps S32 to S34 (i.e., selection of a group of detection images, etc.) for one drawing head 41 that captures a detection image during the vibration of the stage 21 generated when loading the substrate 9, calibration information can be obtained with high precision. As described above, the duration of the vibration of the stage 21 when loading the substrate 9 is 0.5 seconds, and the shooting time of the calibration pattern for one drawing head 41 is longer than this vibration duration. Therefore, it is possible to select a suitable group of detection images that are not affected by the vibration of the stage 21 from among a plurality of detection images captured for this one drawing head 41 in step S31. In addition, for drawing heads 41 other than the above-mentioned one drawing head 41, the acquisition timing of the detection images does not overlap with the above vibration of the stage 21. Therefore, calibration information can be obtained with high precision without re-performing steps S32 to S34 for the other drawing heads 41.

[0150] As described above, in the drawing apparatus 1, the moving time of the calibration camera 53 between adjacent drawing heads 41 is 0.8 seconds. In addition, the shooting time of the calibration pattern for each drawing head 41 in the second calibration method is 1 second. Therefore, the time required to obtain calibration information for all six drawing heads 41 is shorter than the loading and unloading time of the substrate 9 during the above manual loading (e.g., about 15 seconds).

[0151] It should be noted that, in the case where a calibration image group cannot be set even after repeating steps S32 to S34 a specified number of times for one drawing head 41, the calibration of this one drawing head 41 can be aborted. In this case, for example, after the calibration of the other drawing heads 41 is completed, the calibration of the one drawing head 41 for which the calibration has been aborted is performed again. The re-calibration of the one drawing head 41 for which the calibration has been aborted is performed within the above loading and unloading time or after the loading and unloading process of the substrate 9 is completed and before the drawing of the substrate 9 starts.

[0152] As described above, the drawing apparatus 1 that irradiates light onto the substrate 9 to draw a pattern includes: a stage 21, a drawing head 41, a main scanning mechanism (i.e., a first moving mechanism 23), a scale portion 52, a calibration camera 53, a correction image group setting unit 804, a correction information acquisition unit 805, and a drawing control unit 807. A substrate holding portion 25 for holding the substrate 9 is provided on the stage 21. The drawing head 41 irradiates the modulated light onto the substrate 9. The first moving mechanism 23 relatively moves the stage 21 with respect to the drawing head 41 in the main scanning direction (in the above example, the Y direction) parallel to the upper surface 91 of the substrate 9. The scale portion 52 is provided on the stage 21. In a state where the stage 21 is at the loading position where the substrate 9 is loaded and unloaded with respect to the substrate holding portion 25, the scale portion 52 is at the calibration position below the drawing head 41. In a state where the scale portion 52 is at the calibration position, the calibration camera 53 captures calibration patterns irradiated from the drawing head 41 onto the scale portion 52, and acquires a plurality of detection images respectively including the scale portion 52 and the calibration patterns.

[0153] The evaluation value acquisition unit 803 obtains the pattern positions of the calibration patterns in each detection image, that is, the variation evaluation value, for a set of two or more specified numbers (for example, five) of detection images included in the plurality of detection images obtained by the calibration camera 53, that is, the detection image group. This variation evaluation value represents the magnitude of the deviation of the specified number of pattern positions in the detection image group. When the variation evaluation value is equal to or less than a specified threshold value, the correction image group setting unit 804 sets the detection image group as the correction image group. The correction information acquisition unit 805 acquires correction information for correcting the irradiation position of the light from the drawing head 41 based on the specified number of pattern positions of the correction image group. The drawing control unit 807 controls the drawing head 41 and the first moving mechanism 23 based on the drawing data and the correction information, so that the substrate 9 relatively moves with respect to the drawing head 41 in the main scanning direction, and the drawing head 41 performs drawing on the substrate.

[0154] Accordingly, it is possible to prevent a detection image group having a deviation in pattern position caused by interference or the like (for example, vibration of the stage 21) from being set as the correction image group. Therefore, it is possible to obtain correction information with high precision by eliminating the influence of interference or the like. In addition, calibration of the drawing head 41 can be performed in parallel with the loading and unloading of the substrate 9. As a result, it is possible to suppress an increase in the cycle time and perform calibration of the drawing head 41 with high precision. It should be noted that in the drawing apparatus 1, even if the deviation in the pattern position in the detection image group is caused by factors other than the vibration of the stage 21, similarly to the above, it is possible to suppress an increase in the cycle time and perform calibration of the drawing head 41 with high precision.

[0155] As described above, in the first calibration method, when the variation evaluation value is greater than the threshold value, after a predetermined standby time has elapsed since the end of shooting of a plurality of detection images, the calibration camera 53 acquires a new plurality of detection images. In addition, the evaluation value acquisition unit 803 obtains a new variation evaluation value for a new set of detection images (five in the above example) included in the new plurality of detection images, that is, a new detection image group. Moreover, when the new variation evaluation value is equal to or less than the threshold value, the calibration image group setting unit 804 sets this new detection image group as the calibration image group. In this way, when the deviation of the pattern positions in the detection image group is large, after the standby time has elapsed, the acquisition of the detection image group is performed again to set the calibration image group, so that calibration information with high accuracy can be appropriately acquired.

[0156] As described above, in the first calibration method, the deviation of the pattern positions of a predetermined number in the detection image group is caused, for example, by the vibration of the stage 21 when the substrate 9 is loaded into the substrate holding unit 25. In this case, the above-mentioned standby time is preferably equal to or longer than the duration of the vibration of the stage 21 when the substrate 9 is loaded into the substrate holding unit 25 (0.5 seconds in the above example). Thereby, the re-acquisition of the detection image group can be appropriately performed after the vibration of the stage 21 has stopped. As a result, calibration information can be acquired with higher accuracy.

[0157] As described above, in the first calibration method, when the substrate 9 is loaded into the substrate holding unit 25, for example, either automatic loading by the loading device 95 or manual loading by an operator is performed. In this case, the above-mentioned standby time is preferably switched between a first standby time corresponding to automatic loading and a second standby time corresponding to manual loading and different from the first standby time. Thereby, without making the standby time too long, the standby time is determined respectively according to the vibration duration of the stage 21 during automatic loading and the vibration duration of the stage 21 during manual loading, and the re-acquisition of the detection image group can be appropriately performed. As a result, an increase in the cycle time can be appropriately suppressed and calibration information with high accuracy can be appropriately acquired.

[0158] As described above, in the second calibration method, the number of plural detection images acquired by the calibration camera 53 is larger than the number of detection images included in the detection image group. Further, when the variation evaluation value is greater than the threshold value, the evaluation value acquisition unit 803 selects, from the plural detection images, a set of the specified number of detection images different from the detection image group, that is, a new detection image group, and obtains a new variation evaluation value for the new detection image group. Further, when the new variation evaluation value is equal to or less than the threshold value, the correction image group setting unit 804 sets the new detection image group as the correction image group. Thus, when the deviation of the pattern position in the detection image group is large, by selecting another detection image group from the acquired plural detection images and setting it as the correction image group, highly accurate correction information can be appropriately acquired.

[0159] As described above, in the second calibration method, the deviation of the specified number of pattern positions in the detection image group is caused by, for example, the vibration of the stage 21 when the substrate 9 is loaded into the substrate holding unit 25. In this case, the time required for the calibration camera 53 to acquire the plural detection images is preferably longer than the duration of the vibration of the stage 21 when the substrate 9 is loaded into the substrate holding unit 25. Thereby, the detection images not affected by the vibration of the stage 21 are reliably included in the acquired plural detection images. Further, by selecting the detection images as the detection image group, correction information can be acquired with higher accuracy.

[0160] As described above, in Figure 1 In the illustrated drawing apparatus 1, the plural drawing heads 41 that include the above-described drawing head 41 and irradiate the substrate 9 with modulated light are arranged above the scale unit 52 in an arrangement direction (the X direction in the above example) that is parallel to the upper surface of the substrate 9 and inclined with respect to the main scanning direction. Preferably, in a state where the scale unit 52 is located at the calibration position, the calibration camera 53 moves in this arrangement direction and sequentially captures the plural calibration patterns irradiated from the plural drawing heads 41 to the scale unit 52, thereby acquiring the plural detection images corresponding to each of the plural drawing heads 41. Thereby, compared with the case where plural calibration cameras are provided in the calibration unit 5, the structure of the drawing apparatus 1 can be simplified, and the manufacturing cost of the drawing apparatus 1 can be reduced.

[0161] In this case, preferably, the evaluation value acquisition unit 803 obtains a variation evaluation value for each of the plurality of drawing heads 41, and the calibration image group setting unit 804 sets a calibration image group for each of the plurality of drawing heads 41. Further, preferably, the calibration information acquisition unit 805 acquires calibration information for each of the plurality of drawing heads 41, and the drawing control unit 807 controls the plurality of drawing heads 41 and the main scanning mechanism (i.e., the first moving mechanism 23) based on the drawing data and the calibration information for each of the plurality of drawing heads 41, thereby performing drawing on the substrate 9. As a result, it is possible to separately eliminate the influence of interference and the like for each of the plurality of drawing heads 41 and acquire calibration information with high accuracy. As a result, it is possible to suppress an increase in the cycle time and perform calibration of the plurality of drawing heads 41 with high accuracy.

[0162] As described above, the time required from acquiring the plurality of detection images corresponding to each of the plurality of drawing heads 41 by the calibration camera 53 to setting the calibration image group for each of the plurality of drawing heads 41 (steps S21 to S25, steps S31 to 35) is preferably equal to or less than the time required to carry out one substrate 9 from the substrate holding unit 25 and carry a new substrate 9 into the substrate holding unit 25 (i.e., the carry-in / carry-out time). As a result, after the carry-in / carry-out of the substrate 9 is completed, the movement of the stage 21 can be started immediately. Therefore, it is possible to prevent an increase in the cycle time caused by calibration.

[0163] As described above, preferably, the calibration camera 53 acquires the plurality of detection images corresponding to each of the plurality of drawing heads 41 each time a substrate 9 is carried into the substrate holding unit 25. As a result, it is possible to suppress an increase in the cycle time and achieve high-precision drawing.

[0164] The above-described drawing method includes: processes (steps S21 and S31), in a state where the stage 21 provided with the substrate holding unit 25 and the scale unit 52 is located at the loading position for loading and unloading the substrate 9 with respect to the substrate holding unit 25, photographing the calibration pattern irradiated from the drawing head 41 to the scale unit 52 located at the calibration position below the drawing head 41, and obtaining a plurality of detection images respectively including the scale unit 52 and the calibration pattern; processes (steps S22 to S23, S32 to S33), for a set of two or more detection images, that is, a detection image group, included in the plurality of detection images obtained in steps S21 and S31, obtaining the position of the calibration pattern in each detection image, that is, the pattern position, and obtaining a variation evaluation value representing the magnitude of the deviation of the specified number of pattern positions in the detection image group; processes (steps S24 to S25, S34 to S35), when the variation evaluation value is equal to or less than a specified threshold value, setting the detection images as a correction image group; processes (steps S26 and S36), based on the specified number of pattern positions of the correction image group, obtaining correction information for correcting the irradiation position of the light from the drawing head 41; and a process (step S13), based on the drawing data and the correction information, irradiating the modulated light from the drawing head 41 to the substrate 9 that relatively moves in the main scanning direction with respect to the drawing head 41, and performing drawing on the substrate 9. Thus, as described above, it is possible to suppress an increase in the cycle time and perform calibration of the drawing head 41 with high precision.

[0165] In the above-described drawing apparatus 1 and drawing method, various modifications can be made.

[0166] For example, in the drawing apparatus 1, it is not necessarily required to perform both the automatic loading of the substrate 9 by the loading apparatus 95 and the manual loading of the substrate 9 by the operator, and the substrate 9 can be loaded based on only one of them. In addition, the structure of the loading apparatus 95 is not limited to the above-described structure, and various modifications can be made.

[0167] The above variation evaluation value is not necessarily limited to the standard deviation or variance of the specified number of pattern positions, and various modifications can be made, such as the sum of the absolute values of the deviations of the specified number of pattern positions, the arithmetic mean of the absolute values of the deviations, the sum of the squares of the deviations, and the like.

[0168] In the drawing device 1, the time required from the acquisition of a plurality of detection images corresponding to each of the plurality of drawing heads 41 by the calibration camera 53 until the setting of the calibration image group for each of the plurality of drawing heads 41 (steps S21 to S25, steps S31 to 35) may be longer than the time required to carry out one substrate 9 from the substrate holding unit 25 and carry a new substrate 9 into the substrate holding unit 25 (i.e., the carry-in / carry-out time), or may be approximately the same. Even in either case, by carrying out the carry-in / carry-out of the substrate 9 and the calibration of the drawing head 41 in parallel, the cycle time can be shortened.

[0169] In the first calibration method, the standby time may be shorter than the duration of the vibration of the stage 21 when carrying the substrate 9 into the substrate holding unit 25, or may be approximately the same.

[0170] In the second calibration method, the time required for the acquisition of a plurality of detection images by the calibration camera 53 may be shorter than the duration of the vibration of the stage 21 when carrying the substrate 9 into the substrate holding unit 25, or may be approximately the same.

[0171] In the above example, the shooting of the calibration pattern (i.e., the acquisition of the detection image) by the calibration camera 53 is carried out with the calibration camera 53 in a stationary state substantially vertically below each drawing head 41, but it is not limited thereto. For example, the calibration camera 53 may also move in the X direction below the plurality of drawing heads 41 while sequentially shooting the calibration patterns corresponding to the respective drawing heads 41. In this case, the plurality of calibration patterns may also be sequentially shot in the form of a moving image, and a plurality of detection images (still images) corresponding to the respective drawing heads 41 may be extracted from the moving image.

[0172] In the drawing device 1, in the shooting unit 51 of the calibration unit 5, a plurality of (i.e., the same number as the drawing heads 41) calibration cameras 53 corresponding to the plurality of drawing heads 41 may also be arranged in the X direction vertically below the scale unit 52 to almost simultaneously acquire the detection images of the plurality of drawing heads 41.

[0173] In the drawing device 1, the scale unit 52 does not necessarily need to have light transmissivity, and the calibration camera 53 does not necessarily need to be installed on the stage 21. For example, the scale unit 52 may also be a reflector that reflects the light irradiated from the drawing head 41 in a specified direction. The calibration camera 53 may, for example, be fixed to the frame of the drawing device 1 at a position separated from the stage 21, and by receiving the reflected light from the scale unit 52, shoot a detection image including the calibration pattern irradiated onto the scale unit 52 and the scale on the scale unit 52.

[0174] In the light source unit 42 of the drawing head 41, light can also be emitted from two or more light sources when detecting an image is captured. Additionally, the light source unit 42 does not necessarily need to have a plurality of light sources and can also have only one light source.

[0175] The stage 21 only needs to be relatively moved in the main scanning direction with respect to the drawing head 41 by the first moving mechanism 23. Therefore, for example, the stage 21 can also be fixed, and above the stage 21, the drawing head 41 can be moved in the main scanning direction by the first moving mechanism 23. Similarly, the drawing head 41 can also be moved in the sub-scanning direction by the second moving mechanism 24.

[0176] In the drawing apparatus 1, it is not necessarily required to perform calibration every time a substrate 9 is loaded. For example, calibration of the drawing head 41 can also be performed at the end of pattern drawing for two or more specified numbers of substrates 9 each time.

[0177] The above-mentioned substrate 9 is not necessarily limited to a printed circuit board. In the drawing apparatus 1, for example, patterns can also be drawn on a semiconductor substrate, a substrate for a semiconductor package, a glass substrate for a flat panel display device such as a liquid crystal display device or a plasma display device, a glass substrate for a photomask, a substrate for a solar cell panel, etc.

[0178] The structures in the above-described embodiments and each modification can be appropriately combined as long as they do not conflict with each other.

[0179] Although the invention has been described in detail, the above description is illustrative rather than restrictive. Therefore, it can be said that various modifications or modes can be made without departing from the scope of the present invention.

Claims

1. A drawing device that irradiates a substrate with light to draw a pattern, wherein: It has: A stage provided with a substrate holding portion for holding the substrate; A drawing head that irradiates the substrate with modulated light; A main scanning mechanism that relatively moves the stage with respect to the drawing head in a main scanning direction parallel to the upper surface of the substrate; A scale portion provided on the stage and located at a calibration position below the drawing head in a state where the stage is at a loading position for loading and unloading the substrate with respect to the substrate holding portion; A calibration camera that, in a state where the scale portion is at the calibration position, captures a calibration pattern irradiated from the drawing head to the scale portion and obtains a plurality of detection images respectively including the scale portion and the calibration pattern; An evaluation value acquisition unit that, for a set of two or more specified numbers of detection images included in the plurality of detection images obtained by the calibration camera, that is, a detection image group, obtains the position of the calibration pattern in each detection image, that is, the pattern position, and obtains a variation evaluation value indicating the magnitude of the deviation of the specified number of the pattern positions in the detection image group; A correction image group setting unit that, when the variation evaluation value is equal to or less than a specified threshold, sets the detection image group as a correction image group; A correction information acquisition unit that, based on the specified number of the pattern positions of the correction image group, obtains correction information for correcting the irradiation position of the light from the drawing head; And A drawing control unit that, by controlling the drawing head and the main scanning mechanism based on drawing data and the correction information, relatively moves the substrate with respect to the drawing head in the main scanning direction and causes the drawing head to perform drawing on the substrate.

2. The drawing device according to claim 1, wherein: When the variation evaluation value is greater than the threshold, The calibration camera obtains a new plurality of detection images after a specified standby time has elapsed since the end of the shooting of the plurality of detection images, The evaluation value acquisition unit obtains a new variation evaluation value for a set of the specified number of detection images included in the new plurality of detection images, that is, a new detection image group, When the new variation evaluation value is equal to or less than the threshold, the correction image group setting unit sets the new detection image group as the correction image group.

3. The drawing device according to claim 2, wherein: The deviation of the specified number of the pattern positions in the detection image group is caused by the vibration of the stage when loading the substrate into the substrate holding portion, The standby time is equal to or longer than the duration of the vibration of the stage when loading the substrate into the substrate holding portion.

4. The drawing device according to claim 3, wherein: When loading the substrate into the substrate holding portion, either automatic loading by a loading device or manual loading by an operator is performed, The standby time can be switched between a first standby time corresponding to the automatic loading and a second standby time corresponding to the manual loading and different from the first standby time.

5. The drawing device according to claim 1, wherein the number of the plurality of detection images acquired by the calibration camera is larger than the number of detection images included in the detection image group, when the variation evaluation value is greater than the threshold value, the evaluation value acquisition unit selects a set of the specified number of detection images different from the detection image group from the plurality of detection images, that is, a new detection image group, and obtains a new variation evaluation value for the new detection image group. When the new variation evaluation value is equal to or less than the threshold value, the calibration image group setting unit sets the new detection image group as the calibration image group.

6. The drawing device according to claim 5, wherein the deviation of the specified number of the pattern positions in the detection image group is caused by the vibration of the stage generated when loading the substrate into the substrate holding unit, the time required for the calibration camera to acquire the plurality of detection images is longer than the duration of the vibration of the stage when loading the substrate into the substrate holding unit.

7. The drawing device according to any one of claims 1 to 6, wherein a plurality of drawing heads including the drawing head and respectively irradiating modulated light to the substrate are above the scale unit and are arranged in an arrangement direction parallel to the upper surface of the substrate and inclined with respect to the main scanning direction. In a state where the scale unit is located at the calibration position, the calibration camera moves in the arrangement direction and sequentially captures a plurality of calibration patterns respectively irradiated from the plurality of drawing heads to the scale unit, thereby acquiring the plurality of detection images corresponding to each of the plurality of drawing heads. The evaluation value acquisition unit obtains the variation evaluation value for each of the plurality of drawing heads. The calibration image group setting unit sets the calibration image group for each of the plurality of drawing heads. The calibration information acquisition unit acquires the calibration information for each of the plurality of drawing heads. The drawing control unit controls the plurality of drawing heads and the main scanning mechanism based on the drawing data and the calibration information for each of the plurality of drawing heads, thereby performing drawing on the substrate.

8. The drawing device according to claim 7, wherein the time required from acquiring the plurality of detection images corresponding to each of the plurality of drawing heads by the calibration camera to setting the calibration image group for each of the plurality of drawing heads is equal to or less than the time required to unload one substrate from the substrate holding unit and load a new substrate into the substrate holding unit.

9. The drawing device according to claim 7, wherein each time a substrate is loaded into the substrate holding unit, the calibration camera acquires the plurality of detection images corresponding to each of the plurality of drawing heads.

10. A drawing method that irradiates a substrate with light to draw a pattern, Wherein Comprising: a) Step: With the stage provided with a substrate holding portion and a scale portion located at the loading position where the substrate is loaded and unloaded with respect to the substrate holding portion, capture a calibration pattern irradiated from the drawing head to the scale portion at the calibration position below the drawing head, and obtain a plurality of detection images respectively including the scale portion and the calibration pattern; b) Step: For a set of two or more specified numbers of detection images included in the plurality of detection images obtained in the step a), that is, a detection image group, find the position of the calibration pattern in each detection image, that is, the pattern position, and find a variation evaluation value representing the magnitude of the deviation of the specified number of the pattern positions in the detection image group; c) Step: When the variation evaluation value is equal to or less than a specified threshold, set the detection image group as a calibration image group; d) Step: Based on the specified number of the pattern positions of the calibration image group, obtain calibration information for correcting the irradiation position of the light from the drawing head; and e) Step: Based on the drawing data and the calibration information, irradiate the modulated light from the drawing head to the substrate that relatively moves in the main scanning direction with respect to the drawing head, and perform drawing on the substrate.

Images