Drawing device and drawing method

Abstract

To improve throughput in a drawing apparatus that has a first substrate holding part and a second substrate holding part.SOLUTION: A drawing apparatus 1 includes a drawing head 41, a first stage 21a, a second stage 21b, and a first distance measuring sensor 5. While a pattern is drawn on a substrate 9 held by one stage, a sensor element 51 of the first distance measurement sensor 5 acquires a distance between the substrate and a measurement position on a substrate 9 held by the other stage. The drawing head 41 includes a second distance measuring sensor 412 that acquires a distance between the substrate held by the other state and a measurement position on the substrate 9 where the pattern is being drawn. A focus control unit of a control unit 10 controls a focus position of light emitted from the drawing head 41 using information acquired from the substrate 9 by the first distance measurement sensor 5 before the pattern is drawn and information acquired from the second distance measurement sensor 412 while the pattern is drawn on the substrate 9.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a technique for drawing a pattern on a substrate by irradiating the substrate with light. [Background technology]

[0002] Conventionally, patterns are drawn by irradiating light onto a semiconductor substrate having a photosensitive material layer on its surface, a printed circuit board, or a glass substrate for an organic electroluminescence display device or a liquid crystal display device (hereinafter, the photosensitive material layer is collectively referred to as a "substrate.") In such a drawing apparatus, the steps of loading the substrate, aligning the substrate, drawing on the substrate, and unloading the substrate are carried out in sequence.

[0003] In recent years, in order to improve the throughput of drawing devices (the number of substrates processed per unit time), it has been proposed to provide two substrate holders and one drawing head within a single drawing device, and to perform replacement and alignment processing of the substrate on one substrate holder while drawing is being performed on the substrate on the other substrate holder.

[0004] For example, in the step-and-scan scanning projection exposure apparatus of Patent Document 1, while exposure is being performed on a wafer on one stage, which is a substrate holding unit, on the other stage, wafer exchange, alignment measurements, and waiting until exposure on the other stage is completed (see Figure 4).

[0005] Patent Document 2 discloses an autofocus mechanism for a drawing device that draws a pattern by irradiating a substrate with light, in which an optical head is provided with a detector that detects the distance between the optical head and the substrate, and the focus position of the drawing light is adjusted according to the distance. Also, a technology is disclosed in which, depending on the drawing region, a detector in the optical head is used to obtain the variation in the distance in the drawing region before drawing, and autofocus control is performed during drawing based on the variation in the distance. [Prior art documents] [Patent documents]

[0006] [Patent Document 1] International Publication No. 2003 / 010802 [Patent Document 2] JP 2014-197125 A Summary of the Invention [Problem to be solved by the invention]

[0007] Incidentally, in many drawing devices, an autofocus function is provided in the drawing head in order to perform highly accurate drawing on the surface of the substrate. The autofocus function accurately aligns the height direction position of the image formed by the light emitted from the drawing head with the height direction position of the surface of the substrate. However, since the distance measuring sensor required for autofocus is provided in the drawing head, measurements required in relation to autofocus are performed after the substrate is placed below the drawing head. Therefore, there is a time when drawing is not performed even though the substrate is placed below the drawing head. As a result, the throughput cannot be sufficiently improved despite the provision of two substrate holders.

[0008] The present invention has been made in consideration of the above-mentioned problems, and has an object to improve throughput in a drawing apparatus having a first substrate holding part and a second substrate holding part. [Means for solving the problem]

[0009] The invention described in claim 1 is a drawing device that draws a pattern on a substrate by irradiating the substrate with light, the drawing device including a drawing head that emits modulated light, a first substrate holding part that holds a first substrate, a second substrate holding part that holds a second substrate, a moving mechanism that moves the drawing head relatively to the first substrate holding part while a pattern is drawn on the first substrate held by the first substrate holding part by the light emitted from the drawing head, and moves the drawing head relatively to the second substrate holding part while a pattern is drawn on the second substrate held by the second substrate holding part by the light emitted from the drawing head, and a moving mechanism that acquires a distance between a measurement position on the first substrate opposite the first substrate held by the first substrate holding part while a pattern is drawn on the second substrate held by the second substrate holding part, and a measuring mechanism that measures the distance between the first substrate held by the first substrate holding part and a measurement position on the first substrate while a pattern is drawn on the second substrate held by the second substrate holding part The system includes a first distance measurement sensor that faces a second substrate held in a second substrate holding part and obtains a distance between the first substrate held in a holding part and a measurement position on the second substrate while a pattern is being drawn on the first substrate held in the holding part, and a focus control part that controls the focus position of light emitted from the drawing head during drawing of the pattern to be aligned with a height direction position on the surface of the substrate on which the pattern is being drawn, and a second distance measurement sensor that obtains the distance between the drawing head and a measurement position on the substrate on which the pattern is being drawn, and a focus change part that changes the focus position of the light emitted from the drawing head, and the focus control part controls the focus change part using information obtained from the substrate by the first distance measurement sensor before the pattern is drawn and information obtained from the second distance measurement sensor while the pattern is being drawn on the substrate.

[0010] A second aspect of the present invention provides the drawing device according to the first aspect, wherein the measurement accuracy of the first distance measuring sensor is lower than the measurement accuracy of the second distance measuring sensor.

[0011] The invention described in claim 3 is a drawing apparatus as described in claim 1 or 2, wherein before the drawing head starts drawing a pattern on a substrate held by the first substrate holding part or the second substrate holding part, the focus control part uses information acquired by the first distance measuring sensor to bring the focus position of the light emitted from the drawing head closer to the height direction position of the surface of the substrate at the time drawing starts.

[0012] The invention described in claim 4 is the drawing device described in claim 3, wherein the first distance measuring sensor acquires multiple distances to multiple positions while positioning a measurement position at multiple positions near a drawing start position on a substrate held by the first substrate holding part or the second substrate holding part, and the focus control part uses the most frequently occurring distance among the multiple distances as the distance between the first distance measuring sensor and the substrate.

[0013] The invention described in claim 5 is a drawing device described in any one of claims 1 to 4, wherein the first distance measurement sensor includes a sensor element whose absolute position is fixed above the first substrate holding part, and a sensor element whose absolute position is fixed above the second substrate holding part.

[0014] The invention described in claim 6 is a drawing device described in any one of claims 1 to 4, further comprising an alignment camera that faces the first substrate held by the first substrate holding section to capture an image of an alignment mark on the first substrate while a pattern is being drawn on the second substrate held by the second substrate holding section, and that faces the second substrate held by the second substrate holding section to capture an image of the alignment mark on the second substrate while a pattern is being drawn on the first substrate held by the first substrate holding section, and a camera position switching unit that switches the relative position of the alignment camera with respect to the first substrate holding section and the second substrate holding section between a position facing the first substrate held by the first substrate holding section and a position facing the second substrate held by the second substrate holding section, and the relative position of the first distance measuring sensor with respect to the first substrate holding section and the second substrate holding section is switched together with the alignment camera between a position facing the first substrate and a position facing the second substrate by the camera position switching unit.

[0015] The invention described in claim 7 is the drawing apparatus described in claim 1, wherein the first distance measuring sensor is a diffuse reflection type, the focus control unit includes a correction unit that corrects the distance from the first distance measuring sensor to a measurement position on the substrate acquired by the first distance measuring sensor, and the correction unit corrects the distance according to the material forming the surface of the substrate and its vicinity.

[0016] The invention described in claim 8 is a drawing method for drawing a pattern on a substrate by irradiating light onto the substrate, the drawing method comprising the steps of: a) holding a first substrate by a first substrate holding part; b) acquiring a distance between the first distance measuring sensor and a measurement position on the first substrate by a first distance measuring sensor facing the first substrate; c) drawing a pattern on the first substrate by moving the drawing head relatively to the first substrate holding part while emitting modulated light from the drawing head toward the first substrate; d) holding a second substrate by a second substrate holding part while the step c) is being performed; e) acquiring a distance between the first distance measuring sensor and a measurement position on the second substrate by the first distance measuring sensor facing the second substrate while the step c) is being performed; f) after the steps c) and e), drawing a pattern on the second substrate by moving the drawing head relatively to the second substrate holding part while emitting modulated light from the drawing head toward the second substrate; and g) drawing a pattern on the second substrate by moving the drawing head relatively to the second substrate holding part while emitting modulated light from the drawing head toward the second substrate, when a step a) is not performed. and repeating step f), wherein while step f) is being performed, steps a) and b) are performed for a next first substrate, and step c) is performed for the next first substrate after step f) and step b) for the next first substrate, and the drawing head includes a second distance measuring sensor that acquires the distance between the drawing head and a measurement position on the substrate where a pattern is being drawn, and in step c), focus control is performed to align the focus position of light emitted from the drawing head to a position in the height direction of the surface of the first substrate using information acquired from the first substrate by the first distance measuring sensor in step b) and information acquired from the second distance measuring sensor while the pattern is being drawn on the first substrate, and in step f), focus control is performed to align the focus position of light emitted from the drawing head to a position in the height direction of the surface of the second substrate using information acquired from the second substrate by the first distance measuring sensor in step e) and information acquired from the second distance measuring sensor while the pattern is being drawn on the second substrate. Effect of the Invention

[0017] According to the present invention, in a drawing apparatus having a first substrate holding part and a second substrate holding part, the throughput can be improved. [Brief description of the drawings]

[0018] [Figure 1] 1 is a perspective view showing a drawing device according to an embodiment; [Diagram 2] FIG. 1 illustrates a configuration of a computer. [Diagram 3] 2 is a block diagram showing a functional configuration of a control unit and its peripherals. FIG. [Figure 4A] FIG. 2 is a diagram illustrating a flow of operations of the drawing device. [Figure 4B] FIG. 2 is a diagram illustrating a flow of operations of the drawing device. [Diagram 5] FIG. 2 is a diagram showing the positions of the first stage and the second stage. [Figure 6] FIG. 2 is a diagram showing the positions of the first stage and the second stage. [Figure 7] FIG. 2 is a diagram showing the positions of the first stage and the second stage. [Figure 8] FIG. 2 is a diagram showing the positions of the first stage and the second stage. [Figure 9] FIG. 2 is a diagram showing the positions of the first stage and the second stage. [Figure 10] FIG. 2 is a diagram showing the positions of the first stage and the second stage. [Figure 11] FIG. 2 is a diagram for explaining how drawing is performed on a substrate. [Figure 12] 13 is a plan view showing another example of the structure related to the imaging section and the first distance measuring sensor. FIG. [Figure 13] 2 is a block diagram showing a functional configuration of a correction unit and its periphery. FIG. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0019] FIG. 1 is a perspective view showing a drawing apparatus 1 according to an embodiment of the present invention. The drawing apparatus 1 is an apparatus for drawing a pattern on a substrate 9 by irradiating the substrate 9 with light. The drawing apparatus 1 is a twin-stage type direct drawing apparatus that irradiates a spatially modulated light beam onto a substrate 9 having a layer of a photosensitive material on its surface, and scans the light irradiation area on the substrate 9 to draw a pattern. In FIG. 1, three mutually orthogonal directions are indicated by arrows as the X direction, the Y direction, and the Z direction. In the example shown in FIG. 1, the X direction and the Y direction are horizontal directions perpendicular to each other, and the Z direction is a vertical direction. The same applies to other figures.

[0020] The substrate 9 is, for example, a plate-like member having a substantially rectangular shape in a plan view. The substrate 9 is, for example, a printed circuit board in the process of being manufactured. On the (+Z) side surface 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 device 1, a circuit pattern is drawn (i.e., formed) on the resist film of the substrate 9. The type, shape, etc. of the substrate 9 may be changed in various ways.

[0021] The drawing device 1 includes a first transport mechanism 2a, a second transport mechanism 2b, an imaging unit 3, a pattern drawing unit 4, a frame 7, and a control unit 10. The control unit 10 controls the first transport mechanism 2a, the second transport mechanism 2b, the imaging unit 3, the pattern drawing unit 4, etc.

[0022] The frame 7 is a main body base on which each component of the drawing device 1 is attached. The frame 7 includes a substantially rectangular parallelepiped base 71, and a gate-shaped first gantry unit 72 and a second gantry unit 73 that straddle the base 71. The second gantry unit 73 is disposed adjacent to the (+Y) side of the first gantry unit 72. In the following description, the first gantry unit 72 and the second gantry unit 73 are collectively referred to as a "gantry unit 74." The first transport mechanism 2a and the second transport mechanism 2b are attached on the base 71. The first gantry unit 72 supports the imaging unit 3. The second gantry unit 73 supports the pattern drawing unit 4. The frame 7 is placed on a pedestal (not shown).

[0023] The first transport mechanism 2a and the second transport mechanism 2b are mechanisms that hold and move the substrate 9 below (i.e., on the (-Z) side) the imaging unit 3 and the pattern drawing unit 4. The second transport mechanism 2b is disposed adjacent to the (+X) side of the first transport mechanism 2a. The first transport mechanism 2a and the second transport mechanism 2b have approximately the same structure.

[0024] The first transport mechanism 2a includes a first stage 21a and a first moving mechanism 22a. The first stage 21a is a substantially flat first substrate holder that holds the substrate 9 from below in a substantially horizontal state. The first stage 21a is, for example, a vacuum chuck that adsorbs and holds the lower surface of the substrate 9. The first stage 21a may have a structure other than a vacuum chuck. The upper surface 91 of the substrate 9 placed on the first stage 21a is substantially perpendicular to the Z direction (i.e., the up-down direction) and substantially parallel to the X direction and the Y direction.

[0025] The first moving mechanism 22a is a first stage moving mechanism that moves the first stage 21a in a substantially horizontal direction (i.e., a direction substantially parallel to the upper surface 91 of the substrate 9) relative to the imaging unit 3 and the pattern drawing unit 4. The first moving mechanism 22a moves the first stage 21a supported on the guide rail 221a linearly in the Y direction along the guide rail 221a below the imaging unit 3 and the pattern drawing unit 4. This causes the substrate 9 held by the first stage 21a to move in the Y direction. In the following description, the Y direction is also referred to as the "substrate moving direction" or the "main scanning direction". The driving source of the first moving mechanism 22a is, for example, a linear servo motor or a motor attached to a ball screw. The structure of the first moving mechanism 22a may be modified in various ways.

[0026] The second transport mechanism 2b includes a second stage 21b and a second moving mechanism 22b. The second stage 21b is a substantially flat second substrate holder that holds the substrate 9 in a substantially horizontal state from below. The second stage 21b is disposed adjacent to the side (i.e., the (+X) side) of the first stage 21a. The upper surface of the second stage 21b is located at substantially the same height in the vertical direction (i.e., the Z direction) as the upper surface of the first stage 21a. The second stage 21b is, for example, a vacuum chuck that adsorbs and holds the lower surface of the substrate 9. The second stage 21b may have a structure other than a vacuum chuck. The upper surface 91 of the substrate 9 placed on the second stage 21b is substantially perpendicular to the Z direction and substantially parallel to the X direction and the Y direction. The upper surface 91 of the substrate 9 held by the second stage 21b is located at approximately the same height in the vertical direction (that is, approximately the same position in the Z direction) as the upper surface 91 of the substrate 9 held by the first stage 21a.

[0027] The second moving mechanism 22b is a second stage moving mechanism that moves the second stage 21b in a substantially horizontal direction (i.e., a direction substantially parallel to the upper surface 91 of the substrate 9) relative to the imaging unit 3 and the pattern drawing unit 4. The second moving mechanism 22b moves the second stage 21b supported on the guide rail 221b linearly in the Y direction (i.e., the substrate moving direction) along the guide rail 221b below the imaging unit 3 and the pattern drawing unit 4. This causes the substrate 9 held by the second stage 21b to move in the Y direction. The moving direction of the second stage 21b by the second moving mechanism 22b is substantially parallel to the moving direction of the first stage 21a by the first moving mechanism 22a. The driving source of the second moving mechanism 22b is, for example, a linear servo motor or a motor attached to a ball screw. The structure of the second moving mechanism 22b may be modified in various ways.

[0028] The first moving mechanism 22a and the second moving mechanism 22b are arranged side by side in a direction intersecting the substrate moving direction (i.e., the Y direction). In the example shown in Fig. 1, the first moving mechanism 22a and the second moving mechanism 22b are arranged side by side in the X direction, and the second moving mechanism 22b is adjacent to the (+X) side of the first moving mechanism 22a. The first moving mechanism 22a and the second moving mechanism 22b are located at approximately the same height in the vertical direction.

[0029] The first moving mechanism 22a and the second moving mechanism 22b are supported from below by a base 71 of the frame 7. The first moving mechanism 22a and the second moving mechanism 22b extend from the (+Y) side to the (-Y) direction beyond the second gantry section 73, pass below the pattern drawing section 4 supported by the second gantry section 73, and below the imaging section 3 supported by the first gantry section 72, and protrude to the (-Y) side from the first gantry section 72. The first gantry section 72 is located at approximately the same position in the Y direction as the centers in the Y direction of the first moving mechanism 22a and the second moving mechanism 22b.

[0030] In the drawing apparatus 1, the substrate 9 is carried in and out of the first stage 21a in a state in which the first stage 21a is positioned on the (-Y) side of the first gantry section 72. Moreover, the substrate 9 is carried in and out of the second stage 21b in a state in which the second stage 21b is positioned on the (-Y) side of the first gantry section 72.

[0031] As described above, the first gantry unit 72 and the second gantry unit 73 are provided across the first transport mechanism 2a and the second transport mechanism 2b. The first gantry unit 72 includes two support columns extending in the Z direction on both sides of the first transport mechanism 2a and the second transport mechanism 2b in the X direction, and a beam portion connecting the upper ends of the two support columns. The beam portion extends in the X direction above the first transport mechanism 2a and the second transport mechanism 2b. The two support columns of the first gantry unit 72 are connected to the base 71 at their ends on the (-Z) side. The second gantry unit 73 includes two support columns extending in the Z direction on both sides of the first transport mechanism 2a and the second transport mechanism 2b in the X direction, and a beam portion connecting the upper ends of the two support columns. The beam portion extends in the X direction above the first transport mechanism 2a and the second transport mechanism 2b. The two support columns of the second gantry section 73 are connected to the base 71 at their ends on the (-Z) side.

[0032] The imaging unit 3 includes a plurality of alignment cameras 31 (two in the example shown in FIG. 1) and a camera position switching unit 32. The plurality of alignment cameras 31 are arranged in the X direction and movably attached to the beam of the first gantry unit 72. The camera position switching unit 32 is attached to the beam and moves the plurality of alignment cameras 31 in the X direction along the beam. The driving source of the camera position switching unit 32 is, for example, a linear servo motor or a motor attached to a ball screw. In the example shown in FIG. 1, the distance between the two alignment cameras 31 in the X direction is changeable. Note that the number of alignment cameras 31 in the imaging unit 3 may be one or may be three or more.

[0033] Each alignment camera 31 is a camera equipped with an imaging sensor and an optical system (not shown). Each alignment camera 31 is, for example, an area camera that captures a two-dimensional image. The imaging sensor is equipped with, for example, a plurality of elements such as CCDs (Charge Coupled Devices) arranged in a matrix. In each alignment camera 31, the reflected light of illumination light guided from a light source (not shown) to the upper surface 91 of the substrate 9 is guided to the imaging sensor via the optical system. The imaging sensor receives the reflected light from the upper surface 91 of the substrate 9 and captures an image of a substantially rectangular imaging area. As the light source, various light sources such as LEDs (Light Emitting Diodes) can be used. Note that each alignment camera 31 may be another type of camera such as a line camera.

[0034] In the drawing device 1, the camera position switching unit 32 moves the alignment cameras 31 between a first imaging position above the first transport mechanism 2a and a second imaging position above the second transport mechanism 2b. The first imaging position is a position where the alignment cameras 31 face the first stage 21a and the first substrate 9 when imaging. The second imaging position is a position where the alignment cameras 31 face the second stage 21b and the second substrate 9 when imaging. In FIG. 1, the alignment cameras 31 are located at the first imaging position. The alignment cameras 31 capture an image of the top surface 91 of the substrate 9 on the first stage 21a at the first imaging position. The alignment cameras 31 also capture an image of the top surface 91 of the substrate 9 on the second stage 21b at the second imaging position.

[0035] The pattern drawing unit 4 includes a plurality of drawing heads 41 (six in the example shown in FIG. 1) and a drawing head moving mechanism 42. The plurality of drawing heads 41 are arranged in the X direction and movably attached to the beam portion of the second gantry unit 73. The drawing head moving mechanism 42 is attached to the beam portion and moves the plurality of drawing heads 41 integrally in the X direction along the beam portion. The driving source of the drawing head moving mechanism 42 is, for example, a linear servo motor or a motor attached to a ball screw. Note that the number of drawing heads 41 in the pattern drawing unit 4 may be one or more.

[0036] Each drawing head 41 includes a light source, an optical system, and a spatial light modulation element (not shown). As the spatial light modulation element, various elements such as a DMD (Digital Micro Mirror Device) or a GLV (Grating Light Valve) (registered trademark of Silicon Light Machines, Sunnyvale, California) can be used. As the light source, various light sources such as an LD (Laser Diode) can be used. The multiple drawing heads 41 have approximately the same structure.

[0037] In the drawing device 1, the drawing head moving mechanism 42 moves the drawing heads 41 between a first drawing position above the first transport mechanism 2a and a second drawing position above the second transport mechanism 2b. The first drawing position is a position where the drawing head 41 faces the first stage 21a and the first substrate 9 during drawing. The second drawing position is a position where the drawing head 41 faces the second stage 21b and the second substrate 9 during drawing. In FIG. 1, the drawing heads 41 are located at the second drawing position. The drawing heads 41 draw a pattern on the upper surface 91 of the substrate 9 on the first stage 21a at the first drawing position. The drawing heads 41 also draw a pattern on the upper surface 91 of the substrate 9 on the second stage 21b at the second drawing position. When drawing a pattern on the upper surface 91 of the substrate 9 on the first stage 21a, the drawing head moving mechanism 42 also moves the drawing head 41 stepwise in the X direction. Similarly, when a pattern is drawn on the upper surface 91 of the substrate 9 on the second stage 21b, the drawing head moving mechanism 42 also moves the drawing head 41 stepwise in the X direction.

[0038] The first drawing position and the second drawing position are located at approximately the same position in the Y direction as the center of the first moving mechanism 22a and the second moving mechanism 22b in the Y direction. The above-mentioned first imaging position and the second imaging position are also located at approximately the same position in the Y direction as the center of the first moving mechanism 22a and the second moving mechanism 22b in the Y direction. In other words, the multiple drawing heads 41 of the pattern drawing unit 4 and the multiple alignment cameras 31 of the imaging unit 3 are located at approximately the same position in the Y direction as the center of the first moving mechanism 22a and the second moving mechanism 22b in the Y direction.

[0039] When a pattern is drawn at the first drawing position, modulated (i.e., spatially modulated) light is irradiated from the multiple drawing heads 41 of the pattern drawing unit 4 toward the substrate 9 on the first stage 21a below. In parallel with the light irradiation, the substrate 9 is moved horizontally from the (+Y) side of the pattern drawing unit 4 in the (-Y) direction (i.e., substrate movement direction) by the first movement mechanism 22a. As a result, the irradiation area of ​​the light from the multiple drawing heads 41 is relatively main-scanned in the (+Y) direction on the substrate 9, and a pattern (e.g., a circuit pattern) is drawn on the substrate 9. The first movement mechanism 22a is a scanning mechanism that moves the irradiation area of ​​the light from each drawing head 41 in the Y direction on the substrate 9.

[0040] When one main scan is completed, the drawing head moving mechanism 42 moves the drawing head 41 in a stepwise manner by a predetermined distance in the (+X) direction (i.e., sub-scanning), and moves the substrate 9 in the (+Y) direction. That is, in parallel with the irradiation of light from the drawing head 41, the substrate 9 is moved horizontally in the (+Y) direction by the first moving mechanism 22a. As a result, the irradiation area of ​​the light from the multiple drawing heads 41 is relatively main-scanned in the (-Y) direction on the substrate 9, and a pattern is drawn on the substrate 9. Thereafter, in this embodiment, the drawing head 41 moves in a stepwise manner by a predetermined distance in the (+X) direction, and the pattern is further drawn by main-scanning the irradiation area in the (+Y) direction. In this way, in the drawing device 1, drawing is performed on the substrate 9 by a multi-pass method in which the movement of the first stage 21a in the Y direction and the stepwise movement in the X direction are repeated. The drawing of a pattern at the second drawing position is similar to the drawing of a pattern at the first drawing position described above, except that the first stage 21a and the first moving mechanism 22a are changed to the second stage 21b and the second moving mechanism 22b.

[0041] Drawing on the substrate 9 may be performed by a so-called single-pass method. Specifically, in the case of the first stage 21a, the first moving mechanism 22a moves the first stage 21a relatively to the multiple drawing heads 41 in the Y direction, and the irradiation areas of the light from the multiple drawing heads 41 are scanned only once in the Y direction on the upper surface 91 of the substrate 9. This completes drawing on the substrate 9. The same applies to the second stage 21b.

[0042] The number of main scans when a pattern is drawn on the substrate 9 may be one, two, three, or four or more. When multiple main scans are performed, the substrate 9 is preferably moved alternately in the (+Y) direction and the (-Y) direction, and when the movement direction is switched, the drawing head 41 moves stepwise in the (+X) direction relative to the substrate 9. Of course, the stepwise movement of the drawing head 41 may also be in the (-X) direction.

[0043] As described above, in the drawing device 1, the first moving mechanism 22a and the drawing head moving mechanism 42 constitute a mechanism for moving the drawing head 41 relatively to the substrate 9 held by the first stage 21a during drawing. However, when a single-pass operation is performed, the first moving mechanism 22a becomes a mechanism for moving the drawing head 41 relatively to the substrate 9 held by the first stage 21a during drawing. Similarly, in the drawing device 1, the second moving mechanism 22b and the drawing head moving mechanism 42 constitute a mechanism for moving the drawing head 41 relatively to the substrate 9 held by the second stage 21b during drawing. When a single-pass operation is performed, the second moving mechanism 22b becomes a mechanism for moving the drawing head 41 relatively to the substrate 9 held by the second stage 21b during drawing.

[0044] Furthermore, the drawing head moving mechanism 42 also serves as a head position switching unit that switches the position of the drawing head 41 between a position facing the substrate 9 held by the first stage 21a and a position facing the substrate 9 held by the second stage 21b. The drawing head moving mechanism 42 does not need to serve as the head position switching unit, and for example, a moving mechanism that switches the position of the drawing head 41 between a position facing the first stage 21a and a position facing the second stage 21b may be provided, and a mechanism that moves the drawing head 41 stepwise in the X direction may be provided on the moving mechanism. That is, the drawing device 1 may be provided in various forms with a mechanism for moving the drawing head 41 relatively to the substrate 9 held on the first stage 21a during drawing, a mechanism for moving the drawing head 41 relatively to the substrate 9 held on the second stage 21b during drawing, and a mechanism (head position switching unit) for moving the drawing head 41 relatively to the first stage 21a and the second stage 21b between a position facing the substrate 9 held on the first stage 21a and a position facing the substrate 9 held on the second stage 21b.

[0045] In the following description, all of these mechanisms are collectively referred to as the "moving mechanism 2." In the case of the drawing apparatus 1 in FIG. 1, the moving mechanism 2 includes a first moving mechanism 22a, a second moving mechanism 22b, and a drawing head moving mechanism 42. The moving mechanism 2 moves the drawing head 41 relative to the first stage 21a while a pattern is drawn on the substrate 9 held by the first stage 21a (first substrate holding unit) by the light emitted from the drawing head 41, and moves the drawing head 41 relative to the second stage 21b while a pattern is drawn on the substrate 9 held by the second stage 21b (second substrate holding unit) by the light emitted from the drawing head 41.

[0046] The imaging device 1 further includes a first distance measurement sensor 5. The first distance measurement sensor 5 is disposed on the (-Y) side of the beam portion of the first gantry portion 72. The first distance measurement sensor 5 includes a plurality of sensor elements 51. The plurality of sensor elements 51 are arranged in the X direction. The number of sensor elements 51 is, in principle, twice the number of imaging heads 41. The same number of sensor elements 51 as the number of imaging heads 41 are disposed above the first stage 21a, in principle, and the same number of sensor elements 51 as the number of imaging heads 41 are disposed above the second stage 21b. In the example of FIG. 1, the number of imaging heads 41 is 6, and the number of sensor elements 51 is 12. Above the first stage 21a, the pitch of the sensor elements 51 (i.e., the center-to-center interval of the sensor elements 51 in the X direction) is the same as the pitch of the imaging heads 41 (i.e., the center-to-center interval of the imaging heads 41 in the X direction). The pitch of the sensor elements 51 above the second stage 21b is also the same as the pitch of the drawing head 41.

[0047] Each sensor element 51 acquires a distance between itself and the substrate 9 held by the first stage 21a or the second stage 21b located below. More precisely, this measurement acquires a distance between a measurement position on the upper surface 91 of the substrate 9 and a specific portion of the sensor element 51 above the measurement position. The height direction position of the sensor element 51 is acquired in advance by measurement, and the height direction position of the measurement position can be obtained from the height direction position of the sensor element 51 and the acquired distance. Therefore, the measurement of the distance between the sensor element 51 and the measurement position is essentially acquiring the height direction position of the measurement position. More precisely, the output value from the sensor element 51 is converted to the height direction position of the measurement position by the focus control unit 113 of the control unit 10, which will be described later. For example, a linear function is used for the conversion. In principle, the measurement position is directly below the sensor element 51, but it is not limited to being directly below as long as it is approximately below.

[0048] Each sensor element 51 employs a diffuse reflection method. Specifically, a laser light is irradiated from the sensor element 51 to the substrate 9 via a light projecting lens, and the diffuse reflected light from the substrate 9 is received by a light receiving position detection sensor (e.g., a PSD (Position Sensitive Detector) or a CMOS (Complementary Metal-Oxide Semiconductor)) via a light receiving lens to detect the light receiving position. Then, the distance between the sensor element 51 and the measurement position on the substrate 9 is obtained from the light receiving position. Diffuse reflection type sensors are easily available and inexpensive, but the measurement accuracy is relatively low. The wavelength of the light emitted from the first distance measuring sensor 5 may be any wavelength as long as it does not affect the photosensitive material forming the surface (i.e., the upper surface 91) of the substrate 9. The light source of the first distance measuring sensor 5 is preferably a semiconductor laser of visible light or infrared light, and more preferably a semiconductor laser of visible light.

[0049] FIG. 2 is a diagram showing the configuration of the computer 100 included in the control unit 10. The computer 100 is a normal computer including a processor 101, a memory 102, an input / output unit 103, and a bus 104. The bus 104 is a signal circuit that connects the processor 101, the memory 102, and the input / output unit 103. The memory 102 stores programs and various information. The memory 102 is, for example, a RAM (Ramdom Access Memory) or a fixed disk drive. The processor 101 executes various processes (for example, numerical calculations and image processing) while using the memory 102 and the like according to the programs and the like stored in the memory 102. The input / output unit 103 includes a keyboard 105 and a mouse 106 that receive input from an operator, and a display 107 that displays outputs and the like from the processor 101. The control unit 10 may be a programmable logic controller (PLC), a circuit board, or the like, or may be a combination of one or more computers with these.

[0050] 3 is a block diagram showing the functional configuration of the control unit 10 realized by the computer 100 together with the peripheral functional configuration. The control unit 10 includes an imaging control unit 111, a position detection unit 112, a focus control unit 113, a drawing control unit 114, and a storage unit 115. The storage unit 115 is mainly realized by the memory 102. The storage unit 115 stores data of a pattern to be drawn on the substrate 9 (i.e., drawing data) and other information.

[0051] The imaging control unit 111, the position detection unit 112, the focus control unit 113, and the drawing control unit 114 are mainly realized by the processor 101. The imaging control unit 111 controls the imaging unit 3, the first moving mechanism 22a, and the second moving mechanism 22b to obtain marks (which may be parts of a pattern) provided on the upper surface 91 of the substrate 9 on the first stage 21a and the second stage 21b by the alignment camera 31. The image is sent to the storage unit 115 and stored therein.

[0052] The position detection unit 112 detects the position of the substrate 9 (including distortion of the substrate 9) using the image. The drawing control unit 114 controls the movement mechanism 2 and the pattern drawing unit 4 to irradiate light onto the substrate 9 held on the first stage 21a or the second stage 21b to draw a pattern. At this time, the position of the substrate 9 detected by the position detection unit 112 is used to perform drawing while correcting the pattern to be drawn.

[0053] As described above, each drawing head 41 of the pattern drawing unit 4 includes a light source, an optical system, and a light modulation element 411. The light source may be provided integrally with the drawing head 41, or may be provided separately from the drawing head 41. When the light source is separate from the drawing head 41, light from the light source is introduced into the drawing head 41 via an optical system having an optical fiber or the like.

[0054] As shown in FIG. 3, the drawing head 41 further includes a second distance measuring sensor 412 and a focus change unit 413. The second distance measuring sensor 412 acquires the distance between the measurement position on the substrate 9 where the pattern is being drawn. As the measurement position, a drawing position or a position that can be considered to be at the same height as the drawing position is selected, and the second distance measuring sensor 412 practically measures the distance between the drawing head 41 and the upper surface 91 of the substrate 9. To be precise, the second distance measuring sensor 412 acquires the distance between the drawing position on the upper surface 91 of the substrate 9 and a position that is fixed with respect to the drawing head 41 and is directly above the drawing position. However, the distance acquired by the second distance measuring sensor 412 does not need to be the distance between the drawing head 41 and a position directly below it, or the distance between the drawing position and a position directly above it, but may be the height-direction distance between predetermined positions that can be considered as these distances. That is, the second distance measuring sensor 412 may acquire the height-direction distance between the drawing head 41 and a position shifted from the drawing position on the upper surface 91 of the substrate 9.

[0055] The height direction position of the second distance measuring sensor 412 (or the drawing head 41) is acquired in advance by measurement, and the height direction position of the measurement position can be obtained from the height direction position of the second distance measuring sensor 412 and the acquired distance. Therefore, measuring the distance between the second distance measuring sensor 412 and the measurement position is essentially acquiring the height direction position of the measurement position.

[0056] The second distance measurement sensor 412 performs measurements with higher accuracy than the first distance measurement sensor 5. As the second distance measurement sensor 412, for example, an inclined light, such as a laser light, is irradiated onto the surface of the substrate 9, and the light receiving position of the specularly reflected light is detected by a highly accurate light receiving element. The second distance measurement sensor 412 obtains the distance between the drawing head 41 and the substrate 9 based on the light receiving position. As the second distance measurement sensor 412, for example, the one described in the above-mentioned JP 2014-197125 A can be adopted.

[0057] The focus change unit 413 changes the Z-direction position (i.e., the position in the height direction, hereinafter also referred to as the "focus position") of the image formed by the light emitted from the drawing head 41. The focus change unit 413 includes, for example, a focus lens included in the optical system of the drawing head 41, and a drive unit that moves the focus lens along the optical axis. The focus lens may be one or more. The drive unit moves the position of the focus lens along the optical axis, thereby changing the height direction position of the image formed by the light emitted from the drawing head 41.

[0058] Using information from each sensor element 51 of the first distance measurement sensor 5 and information from the second distance measurement sensor 412, the focus control unit 113 performs control to match the focus position of the image formed by the light emitted from the drawing head 41 with the Z-direction position of the surface of the substrate 9 at the drawing position during drawing. That is, the Z-direction position of the drawing position on the substrate 9 fluctuates slightly up and down as the drawing position moves in the main scanning direction, but the focus control unit 113 changes the Z-direction position of the image formed by the light emitted from the drawing head 41 in accordance with this fluctuation. The use of information from the first distance measurement sensor 5 by the focus control unit 113 will be described later.

[0059] As described above, each sensor element 51 of the first distance measurement sensor 5 has lower accuracy and is less expensive than the second distance measurement sensor 412. This makes it possible to suppress an increase in the manufacturing cost of the drawing device 1. When the first distance measurement sensor 5 is composed of multiple sensor elements 51, an increase in the manufacturing cost of the drawing device 1 can be further suppressed. In particular, when the number of sensor elements 51 is twice the number of the drawing heads 41 as in the drawing device 1 of FIG. 1, the effect of suppressing an increase in the manufacturing cost of the drawing device 1 is significant.

[0060] Next, a flow of drawing a pattern on a substrate 9 by the drawing apparatus 1 shown in Fig. 1 will be described. In the drawing apparatus 1, roughly speaking, while drawing is being performed on the substrate 9 held on one of the first stage 21a and the second stage 21b, the substrate 9 is carried onto the other stage and alignment (i.e., positioning) and the like are performed. Then, when drawing on the substrate 9 held on the one stage is completed, drawing on the substrate 9 held on the other stage is started. Also, while drawing is being performed on the substrate 9 on the other stage, the substrate 9 on which the pattern has been written is carried out from one stage, and a new substrate 9 is carried onto the one stage and processing such as alignment is performed.

[0061] 4A and 4B are diagrams showing an example of the flow of the drawing process in the drawing apparatus 1. Steps S11 to S16 on the left side in FIG. 4A and 4B show the flow of the drawing process on the substrate 9 on the first stage 21a, and steps S21 to S26 on the right side in FIG. 4A and 4B show the flow of the drawing process on the substrate 9 on the second stage 21b. In addition, steps located at the same position in the vertical direction in FIG. 4A and 4B are performed in parallel. Specifically, steps S11 to S15 and step S26 are performed in parallel. In addition, step S16 and steps S21 to S25 are performed in parallel. In FIG. 4A and 4B, the operations for the substrate 9 that is first loaded into the drawing apparatus 1 and the substrate 9 that is last unloaded are omitted.

[0062] 4A and 4B, the description begins with a state in which a pattern is drawn on the substrate 9 on the second stage 21b of the second transport mechanism 2b. Also, FIGS. 5 to 10 are conceptual diagrams showing the schematic positions in the Y direction of the first stage 21a and the second stage 21b in the drawing apparatus 1 during the drawing process. In FIGS. 5 to 10, the first stage 21a, the first moving mechanism 22a, the second stage 21b, and the second moving mechanism 22b are drawn with solid lines, and the alignment camera 31, the arrangement of the drawing head 41, and the arrangement of the sensor elements 51 of the first distance measuring sensor 5 are drawn with dashed lines.

[0063] In the following description, regarding the position of the first stage 21a in the Y direction, the position where the first stage 21a overlaps with the alignment camera 31 and / or the drawing head 41 in the vertical direction is called the "processing position", the position where the first stage 21a overlaps with the part on the (-Y) side of the first moving mechanism 22a in the vertical direction is called the "carry-in / out position", and the position where the first stage 21a overlaps with the part on the (+Y) side of the first moving mechanism 22a in the vertical direction is called the "standby position". Also, regarding the position of the second stage 21b in the Y direction, the position where the second stage 21b overlaps with the alignment camera 31 and / or the drawing head 41 in the vertical direction is called the "processing position", the position where the second stage 21b overlaps with the part on the (-Y) side of the second moving mechanism 22b in the vertical direction is called the "carry-in / out position", and the position where the second stage 21b overlaps with the part on the (+Y) side of the second moving mechanism 22b in the vertical direction is called the "standby position". It should be noted that the above-mentioned processing position does not refer to a single point in the Y direction, but rather refers to a predetermined range in the Y direction (i.e., the area where processing is performed) where the alignment camera 31 images the substrate 9 and the drawing head 41 draws a pattern.

[0064] In the drawing apparatus 1, as shown in FIG. 5, with the second stage 21b located at the processing position and the drawing head 41 located at the second drawing position, a pattern is drawn by the drawing head 41 on the substrate 9 on the second stage 21b (step S26). Hereinafter, the substrate 9 held on the second stage 21b or the substrate 9 to be held thereon is referred to as the "second substrate 9." The "second substrate" does not mean the second substrate, but simply means the substrate related to the second stage 21b. In step S26, the pattern drawing unit 4, the second moving mechanism 22b, and the drawing head moving mechanism 42 are controlled by the drawing control unit 114 (see FIG. 3), so that a pattern is drawn on the substrate 9 moving in the (+Y) direction or the (-Y) direction at the processing position.

[0065] In parallel with step S26, the drawn substrate 9 is carried out from the first stage 21a located at the carry-in / out position, and a new substrate 9 is carried in and held on the first stage 21a (steps S11, S12). Hereinafter, the substrate 9 held on the first stage 21a or the substrate 9 to be held thereon will be referred to as the "first substrate 9." The term "first substrate" does not mean the first substrate, but simply means the substrate related to the first stage 21a. When there is no need to distinguish between the first substrate and the second substrate described below, the term will simply be referred to as the "substrate."

[0066] Next, the first stage 21a is moved in the (+Y) direction by the first moving mechanism 22a, and is located at the processing position as shown in Fig. 6. In the state shown in Fig. 6, the second stage 21b remains located at the processing position, and drawing is being performed on the substrate 9 on the second stage 21b. In addition, the alignment camera 31 is located at a first imaging position facing the first substrate 9 held by the first stage 21a (first substrate holding section) by the camera position switching section 32. The interval between the alignment cameras 31 is previously adjusted according to the size of the first substrate 9.

[0067] When the first stage 21a is located at the processing position, the first moving mechanism 22a is controlled by the imaging control unit 111 (see FIG. 3), so that the first stage 21a moves in the (+Y) direction at a predetermined speed. The alignment camera 31 is controlled by the imaging control unit 111 to capture an image at the moment when an alignment mark (not shown) on the first substrate 9 is located below the alignment camera 31, and the captured image is sent to the position detection unit 112. Note that the movement of the first stage 21a may be stopped during the imaging. The imaging is performed for each alignment mark on the first substrate 9. The position detection unit 112 performs pattern matching on the image using a reference image. The pattern matching is performed, for example, by a known pattern matching method (for example, geometric shape pattern matching, normalized correlation search, etc.). As a result, the position of the alignment mark in the image is obtained, and the position of the first substrate 9 relative to the first stage 21a is detected (step S13). Hereinafter, information regarding the position of the substrate 9 acquired by the position detection unit 112 will be referred to as "alignment information."

[0068] The position of the first substrate 9 detected by the position detection unit 112 includes information indicating the coordinates in the X direction and the Y direction of the first substrate 9 relative to the first stage 21a, which is a substrate holding unit, the orientation of the first substrate 9 (i.e., the rotation position), and deformation of the first substrate 9 due to distortion or the like. The information indicating the deformation of the first substrate 9 is information such as the shape of the deformed first substrate 9 and the position of the drawing area on the first substrate 9. The position detection unit 112 corrects the drawing data for the first substrate 9 on the first stage 21a (i.e., alignment processing) based on the detected alignment information. Note that, if the first moving mechanism 22a has a function of rotating the first stage 21a around an axis facing the Z direction, the first substrate 9 may be rotated based on the alignment information. The above description of the alignment regarding the first substrate 9 is also applicable to the processing for the second substrate 9 described later.

[0069] When the portion of the first substrate 9 on the (-Y) side passes under the first distance measuring sensor 5, the outputs from the six sensor elements 51 on the first stage 21a side are recorded in the memory unit 115 of the control unit 10. That is, the distance between the sensor element 51 and the upper surface 91 of the first substrate 9 is repeatedly output from each sensor element 51 and recorded in the memory unit 115 of the control unit 10. The distance between the sensor element 51 and the upper surface 91 of the first substrate 9 corresponds to the position in the height direction of the upper surface 91 of the substrate 9 at the measurement position by the sensor element 51. Therefore, the above measurement acquires the fluctuation of the position in the height direction of the upper surface 91 of the first substrate 9 in the moving range of the measurement position. Hereinafter, the position in the height direction of the upper surface 91 of the substrate 9 at the measurement position or the drawing position is also referred to as the "surface height position". The focus control unit 113 obtains the mode value from the surface height positions at the multiple measurement positions of the first substrate 9 obtained from the information acquired by each sensor element 51 (step S14). Hereinafter, the mode value is referred to as the "prefocus information". The number of pieces of prefocus information acquired is the same as the number of sensor elements 51 of the first distance measuring sensor 5 .

[0070] The substrate 9 has measurement positions that should not be taken as the height of the top surface 91 of the substrate 9, such as through-holes and steps. By adopting the most frequent value of the many surface height positions of the first substrate 9 acquired by each sensor element 51 as the height direction position of the top surface 91 of the first substrate 9, it is possible to obtain a correct surface height position that represents the many surface height positions. Note that the "mode" refers to a value obtained by dividing the height direction position into a number of small ranges, classifying the many surface height positions acquired by each sensor element 51 as those belonging to each small range, and adopting the median value of the small range to which the largest number of surface height positions belong as the correct surface height position that represents the many measurement positions.

[0071] The movement range of the measurement position of each sensor element 51 on the substrate 9 overlaps with the movement of the drawing position when any of the drawing heads 41 starts drawing in a later process. That is, the position of each sensor element 51 in the X direction coincides with the position in the X direction when any of the drawing heads 41 starts drawing in the later drawing. Therefore, each sensor element 51 of the first distance measuring sensor 5 (more precisely, each sensor element 51 on the first substrate 9 side) acquires a plurality of distances to the plurality of positions while positioning the measurement position at a plurality of positions (aligned in the main scanning direction) near the drawing start position on the first substrate 9 held by the first stage 21a, which is the first substrate holding unit. Then, the focus control unit 113 uses the most frequently acquired distance among the plurality of acquired distances as the distance between each sensor element 51 of the first distance measuring sensor 5 and the first substrate 9. As described above, the distance between each sensor element 51 and the first substrate 9 is prefocus information that indicates the surface height position of the substrate 9 at the drawing position at the drawing start time.

[0072] When acquisition of alignment information and prefocus information from the first substrate 9 is completed while a pattern is being drawn on the second substrate 9 held by the second stage 21b (second substrate holding section), the first stage 21a is further moved in the (+Y) direction by the first moving mechanism 22a and positioned at the standby position as shown in FIG. 7 (step S15). In the state shown in FIG. 7, the second stage 21b remains positioned at the processing position (more precisely, a position having a certain range for drawing), and drawing is being performed on the second substrate 9. The first stage 21a waits at the standby position until drawing on the second substrate 9 is completed.

[0073] When the drawing on the second substrate 9 (step S26) is completed, the second moving mechanism 22b moves the second stage 21b in the (-Y) direction, and the second stage 21b is located at the carry-in / out position as shown in FIG. 8. In parallel with this operation, the first moving mechanism 22a moves the first stage 21a in the (-Y) direction, and located at the processing position. Furthermore, the alignment camera 31 is moved from the first imaging position to the second imaging position facing the second substrate 9 held by the second stage 21b (second substrate holding unit) (more precisely, facing when imaging), and the drawing head 41 is moved from the second drawing position to the first drawing position. Then, the pattern drawing unit 4 and the first moving mechanism 22a are controlled by the drawing control unit 114 based on the above-mentioned alignment-processed drawing data and the like, whereby a pattern is drawn on the first substrate 9 on the first stage 21a moving in the Y direction at the processing position (step S16).

[0074] FIG. 11 is a diagram for explaining how drawing is performed on the first substrate 9. Drawing on the second substrate 9 is performed in the same manner. Therefore, in the following description of FIG. 11, the first substrate 9 and the second substrate 9 are collectively referred to as "substrate 9" without distinction. In FIG. 11, six drawing heads 41 are indicated by dashed lines. Each of the 18 regions 8 long in the Y direction drawn on the substrate 9 indicates a region in which one drawing head 41 performs drawing when the substrate 9 moves in the Y direction. When a DMD is used as the light modulation element 411 of the drawing head 41 and a rectangular image of the DMD is projected on the substrate 9 at an angle, to be precise, the multiple regions 8 slightly overlap in the X direction.

[0075] The thick solid arrow 81 indicates the initial movement of the drawing positions of the multiple drawing heads 41. That is, it indicates that the drawing positions move relatively in the (+Y) direction on the substrate 9 as a result of the substrate 9 moving in the (-Y) direction. When the drawing position moves to the end of the (+Y) side of the region 8, the drawing head moving mechanism 42 moves the drawing head 41 in a step in the (+X) direction, thereby moving the drawing position in a step in the (+X) direction on the substrate 9. Then, as the substrate 9 moves in the (+Y) direction, the drawing position moves in the (-Y) direction as indicated by the dashed arrow 82, and drawing is performed on the second region 8. When the drawing position moves to the end of the (-Y) side of the second region 8, the drawing head moving mechanism 42 moves the drawing head 41 in a step in the (+X) direction, thereby moving the drawing position in a step in the (+X) direction on the substrate 9. Then, by moving the substrate 9 in the (-Y) direction, the drawing position moves in the (+Y) direction as indicated by the dashed arrow 83, and drawing in the third region 8 is performed.

[0076] In the example of FIG. 11, drawing is completed by moving the drawing head 41 back and forth once and a half in the Y direction relative to the substrate 9. As described above, the number of drawing heads 41 and the width of the region 8 may be changed in various ways. Preferably, the number of drawing heads 41 is two or more. Drawing may be completed by moving the drawing head 41 in the Y direction, i.e., the main scanning direction, once relative to the substrate 9, or by moving the drawing head 41 in the main scanning direction two or more times. Generally speaking, a pattern is drawn on the first substrate 9 by moving the drawing head 41 relative to the first stage 21a (first substrate holding unit) while emitting modulated light from the drawing head 41 toward the first substrate 9. The same is true for the second substrate 9, except that the first stage 21a is replaced with the second stage 21b (second substrate holding unit).

[0077] When the number of movements in the main scanning direction until drawing is completed is an odd number of times, it is preferable that the standby position is on the opposite side of the loading / unloading position with respect to the drawing head 41 in order to bring the position of the substrate 9 at the time when drawing is completed closer to the loading / unloading position. Conversely, when the number of movements in the main scanning direction until drawing is completed is an even number of times, it is preferable that the standby position and the loading / unloading position are on the same side with respect to the drawing head 41 in order to bring the position of the substrate 9 at the time when drawing is completed closer to the loading / unloading position.

[0078] When drawing in the first region 8 is started, the prefocus information acquired in step S14 is used. In the drawing device 1, very precise drawing is performed. Therefore, even a slight deviation between the height direction position of the drawing position on the surface of the substrate 9, that is, the surface height position and the height direction position where the image of light from the drawing head 41 is formed (hereinafter referred to as the "image height position") is not allowed. While drawing is being performed continuously, the second distance measuring sensor 412 of the drawing head 41 measures the surface height position, and the focus control unit 113 of the control unit 10 controls the focus change unit 413 of the drawing head 41 based on the measurement result. That is, the focus lens in the drawing head 41 is moved minutely along the optical axis. As a result, even if the drawing position moves parallel to the substrate 9, the surface height position and the image height position at the drawing position accurately match. However, since there is no reliable information from the second distance measuring sensor 412 at the start of drawing, there is a possibility that the actual surface height position and the image height position before control may be significantly different. In particular, when the substrate 9 is warped, the surface height position and the image height position may be significantly different at the edge of the substrate 9. Since there is a limit to the speed at which the image height position can be changed, if the surface height position and the image height position are significantly misaligned, it takes time to align the surface height position and the image height position, and a problem occurs in that the surface height position and the image height position cannot be aligned for some time after drawing begins.

[0079] Therefore, in the drawing device 1, the first distance measuring sensor 5 is provided, and the position in the height direction of the surface of the substrate 9 at the drawing position at the start of drawing, i.e., the surface height position at the start of drawing, is obtained as prefocus information before drawing starts, and the surface height position and the image height position are brought close to each other before drawing starts, thereby realizing quick autofocus control immediately after drawing starts. To be precise, the prefocus information obtained by each sensor element 51 of the first distance measuring sensor 5, i.e., the distance between each sensor element 51 and the substrate 9, is converted into the distance between the corresponding drawing head 41 and the substrate 9, and is used for autofocus control at the start of drawing. Obtaining the distance between the drawing head 41 and the substrate 9 by the conversion is substantially equivalent to obtaining the surface height position at the drawing start position. In addition, the surface height position when drawing of one region 8 is completed and drawing of the next region 8 is started can use the surface height position obtained by the second distance measuring sensor 412 at the end of drawing of the previous region 8.

[0080] By providing the first distance measuring sensor 5, it becomes unnecessary to measure the surface height position at the drawing start position using the second distance measuring sensor 412 of the drawing head 41 before drawing starts. If the first distance measuring sensor 5 is not provided, it is necessary to scan the drawing head 41 over a certain distance in the main scanning direction relative to the substrate 9 before drawing starts and obtain the surface height position at the drawing start position using the output from the second distance measuring sensor 412. In contrast, the drawing device 1 can use information from the first distance measuring sensor 5 to start drawing immediately after positioning the drawing head 41 at the drawing start position, thereby improving the throughput of the drawing device 1.

[0081] In the imaging device 1, as shown in FIG. 4B, in parallel with imaging on the first substrate 9 on the first stage 21a (step S16), the second substrate 9 on which imaging has been performed is carried out from the second stage 21b located at the carry-in / out position, and a new second substrate 9 is carried in and held on the second stage 21b (steps S21, S22). Next, the second stage 21b is moved in the (+Y) direction by the second moving mechanism 22b, and alignment information of the second substrate 9 is acquired under the control of the imaging control unit 111 in the same manner as in steps S13 and S14, and prefocus information is acquired almost in parallel therewith (steps S23, S24). These operations are the same as those in the above description of the first substrate 9, except that the first substrate 9 is replaced by the second substrate 9, the first stage 21a is replaced by the second stage 21b, the first moving mechanism 22a is replaced by the second moving mechanism 22b, and the first imaging position is replaced by the second imaging position.

[0082] 9, the second substrate 9 is moved to the processing position under the control of the imaging control unit 111, and while the second substrate 9 is being moved in the (+Y) direction, an image is captured at the moment when the alignment mark is positioned below the alignment camera 31, and the alignment information of the second substrate 9 is acquired by the position detection unit 112 (step S23). Then, correction of the drawing data for the second substrate 9 (i.e., alignment processing) is performed.

[0083] When a portion of the (-Y) side of the second substrate 9 passes under the first distance measurement sensor 5, outputs from the six sensor elements 51 on the second stage 21b side are recorded in the memory unit 115. From the numerous values ​​(surface height positions) of the height direction position of the upper surface 91 of the second substrate 9 obtained from the information acquired by each sensor element 51, the focus control unit 113 obtains the most frequent value as prefocus information (step S24). The prefocus information indicates the height direction position (surface height position) of the upper surface 91 of the second substrate 9 at the corresponding drawing position at the start of drawing.

[0084] When acquisition of alignment information and prefocus information from the second substrate 9 is completed while a pattern is being drawn on the first substrate 9 held by the first stage 21a (first substrate holding unit), the second stage 21b is further moved in the (+Y) direction by the second moving mechanism 22b and is positioned at the standby position as shown in Fig. 10 (step S25). In the state shown in Fig. 10, drawing is being performed on the first substrate 9. The second stage 21b waits at the standby position until drawing on the first substrate 9 is completed.

[0085] When drawing on the first substrate 9 is completed, drawing head 41 moves to the second drawing position, and alignment camera 31 moves to the first imaging position. Then, as described with reference to Fig. 4A, drawing on the second substrate 9 is started (step S26), and during drawing on the second substrate 9, the first substrate 9 is carried out and the next first substrate 9 is carried in (steps S11, S12), and alignment information and prefocus information related to the first substrate 9 are obtained (steps S13, S14), and the first substrate 9 is positioned at the standby position (step S15).

[0086] Even when drawing on the second substrate 9 starts, the prefocus information acquired by the first distance measuring sensor 5 in step S24 is used to quickly start autofocus control. This operation is the same as in the case of the first substrate 9. By providing the first distance measuring sensor 5, it is not necessary to measure the surface height position at the drawing start position using the second distance measuring sensor 412 of the drawing head 41 before drawing starts. As a result, drawing can be started immediately after the drawing head 41 is positioned at the second drawing position, and the throughput of the drawing device 1 can be improved.

[0087] Fig. 12 is a plan view showing another example of the structure related to the imaging unit 3 and the first distance measuring sensor 5 of the drawing device 1. Fig. 12 shows the structure provided in the first gantry unit 72, and other structures of the drawing device 1 are similar to those in Fig. 1.

[0088] A camera position switching unit 32 extending in the X direction is provided on a beam portion of the first gantry unit 72 in Fig. 12. The camera position switching unit 32 moves a camera base 33 in the X direction as shown by an arrow 34. Two alignment cameras 31 are provided on the camera base 33. One of the alignment cameras 31 is attached to the camera base 33 via a camera position adjustment unit 35. The camera position adjustment unit 35 moves the alignment camera 31 relatively in the X direction with respect to the camera base 33. Various mechanisms may be used for the camera position adjustment unit 35, and for example, a linear servo motor or a motor attached to a ball screw is used.

[0089] The camera position adjustment unit 35 changes the distance between the two alignment cameras 31. The camera position switching unit 32 switches the positions of the two alignment cameras 31 between a first imaging position facing the first stage 21a and the first substrate 9 (to be precise, facing the first moving mechanism 22a) and a second imaging position facing the second stage 21b and the second substrate 9 (to be precise, facing the second moving mechanism 22b). Although simplified in the description of FIG. 1, the camera base 33 and the camera position adjustment unit 35 are also provided in the drawing device 1 of FIG. 1. The camera base 33 may be regarded as a part of the camera position switching unit 32. When there is one alignment camera 31, the camera position adjustment unit 35 is not provided. When there are three or more alignment cameras 31, the camera position adjustment unit 35 may be provided individually for all alignment cameras 31 except for one alignment camera 31. Even if the number of alignment cameras 31 is two or more, the positions of all alignment cameras 31 may be fixed relative to camera base 33.

[0090] 12, unlike the case of FIG. 1, the first distance measuring sensor 5 is fixed to the camera base 33. In the example of FIG. 12, six sensor elements 51 of the first distance measuring sensor 5 are fixed to the camera base 33. Preferably, the interval in the X direction of the sensor elements 51, i.e., the pitch in the X direction, is the same as the pitch in the X direction of the drawing heads 41. Of course, the pitch in the X direction of the sensor elements 51 may be different from the pitch in the X direction of the drawing heads 41. The number of the sensor elements 51 is preferably the same as the number of the drawing heads 41, but may be different. The number of the sensor elements 51 is preferably two or more, but may be one.

[0091] The operation of the drawing device 1 having the structure shown in FIG. 12 is similar to the operation described with reference to FIG. 4A and FIG. 4B, except that the first distance measuring sensor 5 moves in the X direction together with the alignment camera 31. That is, while the pattern is being drawn on the second substrate 9 (step S26), the first substrate 9 is carried out and carried in (steps S11, S12), alignment information and prefocus information are acquired (steps S13, S14), and the first substrate 9 waits at the waiting position until the drawing of the pattern on the second substrate 9 is completed (step S15). Then, when the drawing of the pattern on the second substrate 9 is completed, the drawing head 41 moves from the second drawing position to the first drawing position, and at the same time, the alignment camera 31 moves from the first imaging position to the second imaging position. As a result, the first distance measuring sensor 5 also moves from a position facing the first moving mechanism 22a (a position facing the first stage 21a and the first substrate 9 during measurement) to a position facing the second moving mechanism 22b (a position facing the second stage 21b and the second substrate 9 during measurement).

[0092] Thereafter, while the pattern is being drawn on the first substrate 9 (step S16), the second substrate 9 is carried out and carried in (steps S21, S22), alignment information and prefocus information are acquired (steps S23, S24), and the second substrate 9 waits at the waiting position until the pattern is drawn on the first substrate 9 (step S25). When the pattern is drawn on the first substrate 9, the drawing head 41 moves from the first drawing position to the second drawing position, and at the same time, the alignment camera 31 moves from the second imaging position to the first imaging position. As a result, the first distance measuring sensor 5 also moves from a position facing the second moving mechanism 22b to a position facing the first moving mechanism 22a. When drawing on the first substrate 9 and the second substrate 9 starts, the prefocus information acquired in advance is used as described above. This can improve the throughput of the drawing device 1.

[0093] The first distance measuring sensor 5 (each sensor element 51 when the first distance measuring sensor 5 includes a plurality of sensor elements 51 (hereinafter the same)) shown in FIG. 1 and FIG. 12 is not limited to a diffuse reflection type sensor. For example, a specular reflection type or other type may be adopted within a possible range. A diffuse reflection type sensor is inexpensive, but has a disadvantage that when the transmittance of the light used for measurement to the measurement target is high, it cannot perform measurement in the same manner as when the transmittance is low. Therefore, when the transmittance of the light used for measurement to the measurement target is high, as shown in FIG. 13, the focus control unit 113 of the drawing device 1 is provided with a correction unit 12 that corrects the distance from the first distance measuring sensor 5 (each sensor element 51) to the measurement position on the substrate 9 acquired by the first distance measuring sensor 5. That is, the surface height position to be measured is corrected. In the case of the above embodiment, the correction unit 12 corrects the prefocus information. Note that FIG. 13 shows only the focus control unit 113 and the first distance measuring sensor 5, and the illustration of other components is omitted.

[0094] The correction is preferably performed when the transmittance of the material forming the surface of the substrate 9 and its vicinity for the wavelength of the light emitted from the first distance measuring sensor 5 is 50% or more, preferably 60% or more, and more preferably 70% or more. Such a material forming the surface of the substrate 9 and its vicinity is soda lime glass on which a resist film is formed or a dry film (e.g., polyethylene terephthalate) on which a resist film is formed. A protective film may be further formed on the resist film. Of course, the materials requiring correction are not limited to these materials. The wavelength of the light emitted from the first distance measuring sensor 5 may be any wavelength that does not affect the photosensitive material forming the upper surface 91 of the substrate 9. It is preferable that the wavelength of the light is visible light or infrared light having a wavelength of 600 nm or more. For example, the wavelength is 660 nm.

[0095] When correction by the correction unit 12 is necessary, for example, a function showing the relationship between the output from the first distance measuring sensor 5 and the distance (or a function showing the relationship between the output and the surface height position) is obtained in advance by a calibration operation, and the correction unit 12 obtains the distance between the first distance measuring sensor 5 and the substrate 9 by applying the output from the first distance measuring sensor 5 to this function. The function is preferably a linear function. By providing the correction unit 12, a diffusion type sensor can be used as the first distance measuring sensor 5 even if the material forming the surface of the substrate 9 is transparent to the light used for measurement.

[0096] The above-described drawing device 1 can be modified in various ways.

[0097] The drawing head 41 is not limited to one that emits two-dimensionally spatially modulated light, but may be one that emits linear light extending in a direction intersecting the main scanning direction and one-dimensionally spatially modulated light. Furthermore, the drawing head 41 may emit spot-shaped light and modulate this light while scanning in a direction intersecting the main scanning direction. As the drawing head 41, various types of heads that emit modulated light can be used.

[0098] The substrate holding portion that holds the substrate 9 is not limited to a stage-like portion such as the first stage 21a or the second stage 21b. Various forms can be adopted as the first substrate holding portion that holds the first substrate 9 and the second substrate holding portion that holds the second substrate 9. For example, the first substrate holding portion and the second substrate holding portion may hold the outer edge of the substrate 9 with a claw-like portion, or may hold the center of the lower surface of the substrate 9 by suction.

[0099] The moving mechanism 2 is not limited to that shown in the above embodiment. The moving mechanism 2 moves the drawing head 41 relatively to the first substrate holding part while a pattern is drawn on the first substrate 9 held by the first substrate holding part by the light emitted from the drawing head 41, and moves the drawing head 41 relatively to the second substrate holding part while a pattern is drawn on the second substrate 9 held by the second substrate holding part by the light emitted from the drawing head 41. Here, since it is preferable that the movement of the first substrate 9 during drawing on the first substrate 9 and the movement of the second substrate 9 during measurement on the second substrate 9 are performed independently, the moving mechanism 2 preferably includes a first substrate moving mechanism (different from the above-mentioned first moving mechanism 22a, this has a broader definition) that moves the first substrate 9 horizontally relative to the drawing head 41 and the first distance measurement sensor 5, and a second substrate moving mechanism (different from the above-mentioned second moving mechanism 22b, this has a broader definition) that moves the second substrate 9 horizontally relative to the drawing head 41 and the first distance measurement sensor 5 independently of the first substrate moving mechanism.

[0100] Furthermore, since it is preferable to fix the position of the drawing head 41 as much as possible during drawing to minimize positional misalignment between the drawing head 41 and the first substrate 9 and the second substrate 9, it is preferable that the first substrate moving mechanism includes a first moving mechanism 22a that moves the first substrate 9 in a straight line in the main scanning direction, as shown in Figure 1, and it is also preferable that the second substrate moving mechanism includes a second moving mechanism 22b that moves the second substrate 9 in a straight line in the main scanning direction.

[0101] In the example of FIG. 1, the position of the substrate 9 has been described as any one of the "carry-in / out position," "processing position," and "standby position," but for example, the "carry-in / out position" and the "standby position" may be the same position. Furthermore, depending on the structure of the robot that carries the substrate 9 in and out, the "carry-in / out position" and the "processing position" may overlap. In this case, the substrate 9 may only move within the movement range during drawing.

[0102] In the example of FIG. 1, drawing head moving mechanism 42 that moves drawing head 41 in the X direction switches drawing head 41 between a position facing the first substrate holding part and a position facing the second substrate holding part. Thus, movement mechanism 2 conceptually includes a head position switching part that switches drawing head 41 between a position facing the first substrate holding part and a position facing the second substrate holding part. The head position switching part may be provided separately from a mechanism that moves drawing head in the X direction during drawing. Thus, movement mechanism 2 includes a first substrate moving mechanism, a second substrate moving mechanism, and a head position switching part.

[0103] The first distance measuring sensor 5 obtains the distance between the first substrate 9 held by the first substrate holding section and a measurement position on the first substrate 9 while a pattern is being drawn on the second substrate 9 held by the second substrate holding section, and obtains the distance between the second substrate 9 held by the second substrate holding section and a measurement position on the second substrate 9 while a pattern is being drawn on the first substrate 9 held by the first substrate holding section. To achieve this operation, in FIG. 1, the first distance measuring sensor 5 includes a sensor element 51 whose absolute position is fixed above the first substrate holding section, and a sensor element 51 whose absolute position is fixed above the second substrate holding section. Here, the "absolute position" refers to a position relative to the space (i.e., the room) in which the frame 7 of the drawing device 1 is installed. The absolute position of the sensor element 51 may be achieved by fixing the sensor element 51 to a portion other than the gantry section 74.

[0104] By fixing the absolute positions of the sensor elements 51, the error in the distance acquired by the sensor elements 51 can be kept small, and the sensor elements 51 can be easily used for autofocus control. When the absolute positions of the sensor elements 51 are fixed, the number of sensor elements 51 is greater than in the case of Fig. 12, but since the sensor elements 51 are inexpensive sensors, the manufacturing cost of the device will not increase significantly.

[0105] The number of sensor elements 51 whose absolute positions are fixed above the first substrate holding part (first stage 21a in the case of FIG. 1) may be 1 or may be 2 or more. The number of sensor elements 51 whose absolute positions are fixed above the second substrate holding part (second stage 21b in the case of FIG. 1) may be 1 or may be 2 or more. In the example of FIG. 1, the minimum number of sensor elements 51 is 2.

[0106] When the number of sensor elements 51 facing one substrate 9 at the same time is two or more, the first distance measuring sensor 5 acquiring the distance between the first distance measuring sensor 5 and the measurement position on the substrate 9 means acquiring the distance between each sensor element 51 and the corresponding measurement position on the substrate 9. When the number of sensor elements 51 facing one substrate 9 is one, the first distance measuring sensor 5 acquiring the distance between the first distance measuring sensor 5 and the measurement position on the substrate 9 means acquiring the distance between one sensor element 51 and the corresponding measurement position on the substrate 9.

[0107] In the example of FIG. 12, the relative position of the first distance measuring sensor 5 with respect to the first substrate holding part, which is the first stage 21a, and the second substrate holding part, which is the second stage 21b, is switched by the camera position switching part 32 together with the alignment camera 31 between a position facing the first substrate 9 held by the first substrate holding part and a position facing the second substrate 9 held by the second substrate holding part. In this case, the minimum value of the number of sensor elements 51 of the first distance measuring sensor 5 is 1. Note that the first distance measuring sensor 5 may be fixed to a part other than the camera base 33 as long as it moves together with the alignment camera 31. The camera position switching part 32 may have various structures as long as it switches the relative position of the alignment camera 31 with respect to the first substrate holding part and the second substrate holding part between a position facing the first substrate 9 held by the first substrate holding part and a position facing the second substrate 9 held by the second substrate holding part.

[0108] In the above-described drawing device 1, the focus control unit 113 uses the prefocus information acquired by the first distance measuring sensor 5 to bring the focus position (image height position) of the drawing head 41 close to the position (surface height position) of the surface of the substrate 9, and realizes starting drawing of a pattern while performing autofocus control immediately after the drawing head 41 is positioned at the first or second drawing position. However, the information acquired by the first distance measuring sensor 5 is not limited to the prefocus information acquired as described above.

[0109] For example, in the above embodiment, the surface height position at the position where the first main scan is started is acquired, but the surface height position at the position where all main scans in the (+Y) direction and the (-Y) direction are started may be acquired. Furthermore, the first distance measurement sensor 5 may acquire the variation of the surface height position over the entire length of all main scans, and this information may be used when drawing a pattern using the second distance measurement sensor 412. For example, the first distance measurement sensor 5 may detect a position where an error is likely to occur in the autofocus control using the second distance measurement sensor 412 in each main scan, and the detected position may be used to prevent a control error during drawing. In either case, the measurement by the first distance measurement sensor 5 is performed in the above steps S14 and S24. As described above, the focus control unit 113 may control the focus change unit 413 while using information acquired from the substrate 9 by the first distance measurement sensor 5 before drawing the pattern and information acquired from the second distance measurement sensor 412 while drawing the pattern on the substrate 9 in various ways.

[0110] By utilizing information from the first distance measurement sensor 5 and information from the second distance measurement sensor 412, the focus control unit 113 acquires information from the first distance measurement sensor 5 from the substrate 9 held by one substrate holding unit while drawing a pattern on the substrate 9 held by the other substrate holding unit, and by utilizing the information acquired by the first distance measurement sensor when drawing a pattern on the substrate held by the other substrate holding unit, focus control can be performed efficiently when drawing the pattern, thereby improving throughput.

[0111] In the above embodiment, the first distance measuring sensor 5 measures the vicinity of the drawing start position, and the most frequent value of the distance between the sensor elements 51 and the substrate 9 is obtained as prefocus information, but the prefocus information may be an average value or a median value of the distance. Even with these pieces of information, the focus control unit 113 can use the information obtained by the first distance measuring sensor 5 to bring the focus position (image height position) of the light emitted from the drawing head 41 closer to the surface height position of the substrate 9 at the time of drawing start, before the drawing head 41 starts drawing a pattern on the substrate 9 held by the first substrate holding unit or the second substrate holding unit.

[0112] In the example of FIG. 1, the number of sensor elements 51 of the first distance measuring sensor 5 is preferably twice the number of drawing heads 41. This makes it possible to obtain the distance between the drawing heads 41 and the substrate 9 at the position where each drawing head 41 starts drawing. In the example of FIG. 12, the number of sensor elements 51 of the first distance measuring sensor 5 is preferably the same as the number of drawing heads 41. However, the number of sensor elements 51 of the first distance measuring sensor 5 is not limited to the above example. Even if the measurement position of the sensor element 51 does not coincide with the drawing start position of the drawing head 41, the distance (or the surface height position) between the drawing head 41 and the substrate 9 at the drawing start position of each drawing head 41 can be obtained by, for example, linearly interpolating the measured values ​​of the multiple sensor elements 51.

[0113] In the drawing apparatus 1, the first transport mechanism 2a may further include one or more of a moving mechanism that moves the first substrate holding part (first stage 21a) in the X direction, a rotating mechanism that rotates the first substrate holding part about a rotation axis extending in the Z direction, and a lifting mechanism that moves the first substrate holding part in the Z direction. For example, a linear servo motor can be used as the moving mechanism and the lifting mechanism. For example, a servo motor can be used as the rotating mechanism. The structures of the moving mechanism, the rotating mechanism, and the lifting mechanism may be changed in various ways. The second transport mechanism 2b is similar to the first transport mechanism 2a.

[0114] In the drawing apparatus 1, the number of substrate holding parts may be three or more. In this case, it is preferable that the number of one or more drawing heads 41 (hereinafter referred to as a "drawing head group") used simultaneously when drawing on the same substrate 9 is less than the number of substrate holding parts (and is one or more), the number of one or more alignment cameras 31 (hereinafter referred to as a "camera group") used simultaneously when imaging the same substrate 9 is also less than the number of substrate holding parts (and is one or more), and the number of first distance measuring sensors 5 (i.e., one or more sensor elements 51 used simultaneously when measuring the same substrate 9) is also less than the number of substrate holding parts (and is one or more). The process executed in each substrate holding part is similar to the process executed for the first substrate holding part and the second substrate holding part.

[0115] With the above configuration, by using a smaller number of drawing head groups than the number of substrate holding parts, a smaller number of camera groups than the number of substrate holding parts, and a smaller number of first distance measuring sensors 5 than the number of substrate holding parts, while drawing is being performed on one substrate 9, it is possible to obtain alignment information of the other substrates 9 and information from the first distance measuring sensors 5, thereby improving throughput. Since a pattern drawing operation generally takes time, it is preferable that the number of drawing head groups is one less than the number of substrate holding parts.

[0116] The above-mentioned substrate 9 is not necessarily limited to a printed circuit board. The imaging device 1 may perform imaging on, for example, a semiconductor substrate, a glass substrate for a flat panel display device such as a liquid crystal display device or an organic EL display device, a glass substrate for a photomask, a substrate for a solar panel, or the like.

[0117] The configurations in the above-described embodiment and each of the modified examples may be combined as appropriate as long as they are not mutually inconsistent. [Explanation of symbols]

[0118] 1 Drawing device 2 Moving mechanism 5. First distance sensor 9 Boards (First Board, Second Board) 12 Correction section 21a First stage (first substrate holding part) 21b Second stage (second substrate holding part) 31 Alignment Camera 32 Camera position switching section 41 Drawing head 51 Sensor elements 113 Focus control section 412 Second distance measuring sensor 413 Focus change section S11~S16, S21~S26 steps

Claims

1. 1. A drawing apparatus for drawing a pattern on a substrate by irradiating the substrate with light, comprising: A drawing head that emits modulated light; a first substrate holding portion that holds a first substrate; a second substrate holding portion that holds a second substrate; a moving mechanism that moves the drawing head relative to the first substrate holding part while a pattern is drawn on a first substrate held by the first substrate holding part by the light emitted from the drawing head, and moves the drawing head relative to the second substrate holding part while a pattern is drawn on a second substrate held by the second substrate holding part by the light emitted from the drawing head; a first distance measuring sensor that faces a first substrate held by the first substrate holding unit and obtains a distance between a measurement position on the first substrate while a pattern is being drawn on the second substrate held by the second substrate holding unit, and that faces a second substrate held by the second substrate holding unit and obtains a distance between a measurement position on the second substrate while a pattern is being drawn on the first substrate held by the first substrate holding unit; a focus control unit that performs control to align a focus position of light emitted from the drawing head during drawing of a pattern with a position in a height direction of a surface of a substrate on which the pattern is drawn; Equipped with The imaging head is a second distance measuring sensor for acquiring a distance between the measurement position on the substrate where the pattern is being drawn; a focus changing unit that changes a focus position of light emitted from the drawing head; Including, A drawing device characterized in that the focus control unit controls the focus change unit using information obtained from the substrate by the first distance measurement sensor before drawing the pattern and information obtained from the second distance measurement sensor while drawing the pattern on the substrate.

2. The drawing device according to claim 1 , A drawing device, characterized in that the measurement accuracy of the first distance measuring sensor is lower than the measurement accuracy of the second distance measuring sensor.

3. 3. The drawing device according to claim 1, A drawing device characterized in that before the drawing head starts drawing a pattern on a substrate held by the first substrate holding part or the second substrate holding part, the focus control part uses information acquired by the first distance measuring sensor to bring the focus position of light emitted from the drawing head closer to the height direction position of the surface of the substrate at the start of drawing.

4. The drawing device according to claim 3, A drawing device characterized in that the first distance measuring sensor acquires multiple distances to multiple positions while positioning a measurement position at multiple positions near a drawing start position on a substrate held by the first substrate holding unit or the second substrate holding unit, and the focus control unit uses the most frequently occurring distance among the multiple distances as the distance between the first distance measuring sensor and the substrate.

5. 5. The drawing device according to claim 1, a drawing apparatus, characterized in that the first distance measurement sensor includes a sensor element whose absolute position is fixed above the first substrate holding part, and a sensor element whose absolute position is fixed above the second substrate holding part.

6. 5. The drawing device according to claim 1, an alignment camera that faces the first substrate held by the first substrate holding unit to capture an image of an alignment mark on the first substrate while a pattern is being drawn on the second substrate held by the second substrate holding unit, and that faces the second substrate held by the second substrate holding unit to capture an image of the alignment mark on the second substrate while a pattern is being drawn on the first substrate held by the first substrate holding unit; a camera position switching unit that switches a relative position of the alignment camera with respect to the first substrate holding unit and the second substrate holding unit between a position facing the first substrate held by the first substrate holding unit and a position facing the second substrate held by the second substrate holding unit; Further equipped with A drawing device characterized in that the relative position of the first distance measuring sensor with respect to the first substrate holding unit and the second substrate holding unit is switched together with the alignment camera between a position facing the first substrate and a position facing the second substrate by the camera position switching unit.

7. The drawing device according to claim 1 , the first distance measuring sensor is a diffuse reflection type, the focus control unit includes a correction unit that corrects a distance from the first distance measuring sensor to a measurement position on a substrate, the distance being acquired by the first distance measuring sensor; The drawing apparatus, wherein the correction unit corrects the distance in accordance with a material forming the surface of the substrate and its vicinity.

8. A method for drawing a pattern on a substrate by irradiating the substrate with light, comprising the steps of: a) holding a first substrate by a first substrate holding part; b) acquiring a distance between a first distance measuring sensor facing the first substrate and a measurement position on the first substrate; c) drawing a pattern on the first substrate by emitting modulated light from a drawing head toward the first substrate while moving the drawing head relative to the first substrate holding part; d) holding the second substrate by a second substrate holding part while the step c) is being performed; e) acquiring a distance between the first distance measuring sensor and a measurement position on the second substrate by the first distance measuring sensor facing the second substrate while the step c) is being performed; f) after the steps c) and e), drawing a pattern on the second substrate by moving the drawing head relative to the second substrate holding part while emitting modulated light from the drawing head toward the second substrate; and g) repeating steps a) through f); and Equipped with While the step f) is being performed, the steps a) and b) are performed on a subsequent first substrate, and the step c) is performed on the subsequent first substrate after the step f) and the step b) on the subsequent first substrate; a second distance measuring sensor for acquiring a distance between the drawing head and a measurement position on the substrate where a pattern is being drawn, in the step c), a focus control is performed to align a focus position of light emitted from the drawing head with a position in a height direction of a surface of the first substrate, using information acquired from the first distance measuring sensor in the step b) and information acquired from the second distance measuring sensor while a pattern is being drawn on the first substrate; A drawing method characterized in that in step f), focus control is performed to align the focus position of light emitted from the drawing head to a height direction position on the surface of the second substrate using information obtained from the second substrate by the first distance measuring sensor in step e) and information obtained from the second distance measuring sensor while drawing a pattern on the second substrate.

Images