Drawing apparatus

Abstract

A drawing control unit of the drawing apparatus controls a light modulation unit (44), and when a substrate is moved together with a stage by a stage moving mechanism and a target region on the substrate passes through a plurality of irradiation positions, the light modulation unit (44) modulates light emitted by the light modulation unit (44). An image of the same shape is sequentially formed on the target region at each of the plurality of irradiation positions. The lens movement control unit controls the autofocus mechanism (5) so that the number of unit movements, which is the number of times the second lens group (452) ascends and descends during the period in which the image is formed in the target region at the plurality of irradiation positions, is smaller than the number of the plurality of divided modulation regions in the light modulation unit (44). As a result, it is possible to suppress a reduction in drawing accuracy due to micro-vibration when the second lens group (452) is moved by the autofocus mechanism (5).

Description

Technical Field

[0001] The present invention relates to a drawing device for drawing a pattern by irradiating light onto a substrate.

[0002] [Reference to related applications]

[0003] This application claims priority to Japanese patent application JP2023-137508 filed in Japan on August 25, 2023, and incorporates the entire disclosure of that application into this application. Background Art

[0004] In the past, there is a known direct drawing device that draws a pattern by irradiating a printed wiring board (hereinafter, also referred to as a "substrate") on a stage with modulated light and scanning the irradiated area of ​​the light on the substrate. In such a direct drawing device, an automatic focusing mechanism is provided to cope with the unevenness of the substrate surface.

[0005] For example, the autofocus mechanism provided in the drawing device of Japanese Patent Gazette No. 2016-31502 (Document 1) includes: a detector for detecting changes in the distance between the optical head and the surface of the substrate; a lifting mechanism for holding the lens of the projection optical system and lifting it; and a control unit for calculating the lifting amount of the lens based on the change amount detected by the detector.

[0006] However, in the drawing device such as that in Document 1, when the autofocus mechanism is working, the lens etc. may generate micro-vibration due to the driving load applied to the lifting mechanism etc. In the future, if the pattern is required to be more precise, the variation of the line width of the pattern caused by the micro-vibration of the lens etc. may not converge to the desired accuracy. Summary of the invention

[0007] An object of the present invention is to suppress a decrease in imaging accuracy due to micro vibration when a lens group is moved by an autofocus mechanism.

[0008] A first aspect of the present invention is a drawing device for drawing a pattern by irradiating light onto a substrate, wherein the device comprises: a stage for holding the substrate; a drawing head for irradiating modulated light onto the substrate; a stage moving mechanism for moving the stage relative to the drawing head in a scanning direction parallel to the upper surface of the substrate; and a control unit for controlling the drawing head. The drawing head comprises: an illumination optical system for receiving light emitted from a light source; a light modulating unit for modulating the light guided by the illumination optical system; a projection optical system for guiding the light modulated by the light modulating unit toward the substrate; and an automatic focusing mechanism for adjusting the focus position of the light emitted from the drawing head according to the change in the distance between the projection optical system and the substrate. The light modulation area of ​​the light modulating unit includes a plurality of divided modulation areas corresponding to a plurality of irradiation positions arranged along the scanning direction below the drawing head. The projection optical system comprises: a first lens group for receiving light modulated by the light modulating unit; and a second lens group for guiding the light guided by the first lens group toward the substrate. The autofocus mechanism includes: a sensor unit that measures the distance between the second lens group and the substrate in the vertical direction; and a lens moving mechanism that supports the second lens group and moves the second lens group in the vertical direction based on the output from the sensor unit, thereby adjusting the focus position of the light emitted from the drawing head. The control unit includes: a drawing control unit that controls the light modulation unit to sequentially form an image of the same shape for the one region at each of the plurality of irradiation positions when the substrate is moved together with the stage by the stage moving mechanism so that the one region passes through the plurality of irradiation positions; and a lens moving control unit that controls the autofocus mechanism so that the number of unit movements is less than the number of the plurality of divided modulation regions, the number of unit movements being the number of times the second lens group is raised and lowered during the period when the image of the one region is formed at the plurality of irradiation positions.

[0009] According to the present invention, it is possible to suppress a decrease in the imaging accuracy due to micro vibration when the lens group is moved by the autofocus mechanism.

[0010] According to a second aspect of the present invention, in the drawing device described in the first aspect, the unit movement number is one or less.

[0011] According to mode 3 of the present invention, in the drawing device described in mode 1 or 2, the lens movement control unit limits the maximum moving speed or maximum acceleration of the second lens group based on the lens moving mechanism according to information related to the moving speed of the stage in the scanning direction based on the stage moving mechanism.

[0012] A fourth aspect of the present invention is a drawing device that draws a pattern by irradiating light onto a substrate, wherein the device comprises: a stage that holds the substrate; a drawing head that irradiates modulated light onto the substrate; and a stage moving mechanism that moves the stage relative to the drawing head in a scanning direction parallel to the upper surface of the substrate. The drawing head comprises: an illumination optical system that receives light emitted from a light source; a light modulating unit that modulates the light guided by the illumination optical system; a projection optical system that guides the light modulated by the light modulating unit toward the substrate; and an automatic focusing mechanism that adjusts the focus position of the light emitted from the drawing head according to changes in the distance between the projection optical system and the substrate. The projection optical system comprises: a first lens group that receives light modulated by the light modulating unit; and a second lens group that guides the light guided by the first lens group toward the substrate. The autofocus mechanism includes: a sensor unit that measures the distance between the second lens group and the substrate in the vertical direction; and a lens moving mechanism that supports the second lens group and moves the second lens group in the vertical direction based on the output from the sensor unit to adjust the focus position of the light emitted from the drawing head. Based on information related to the moving speed of the stage in the scanning direction by the stage moving mechanism, the maximum moving speed or maximum acceleration of the second lens group by the lens moving mechanism is limited.

[0013] According to a fifth aspect of the present invention, in the drawing device described in the fourth aspect, the stage moving mechanism can also move the stage relative to the drawing head in a sub-scanning direction parallel to the upper surface of the substrate and perpendicular to the scanning direction. In the drawing device, the following processing is repeatedly performed to draw a predetermined pattern on the substrate: the substrate is relatively moved in the scanning direction while the substrate is irradiated with modulated light from the drawing head, and one of the plurality of drawing areas arranged in the sub-scanning direction is drawn, and after the drawing of the one drawing area is completed, the substrate is relatively displaced by a predetermined distance in the sub-scanning direction relative to the drawing head, so that the drawing head is located at a position corresponding to an undrawn drawing area adjacent to the one drawing area among the plurality of drawing areas. The maximum moving speed or maximum acceleration of the second lens group based on the lens moving mechanism is also limited according to the maximum value of the vertical movement distance of the second lens group when drawing the one drawing area.

[0014] The above-mentioned object and other objects, features, aspects and advantages will become more apparent from the following detailed description of the present invention with reference to the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1It is a perspective view showing a drawing device according to one embodiment.

[0016] Figure 2 It is a diagram showing the structure of the control unit.

[0017] Figure 3 It is a diagram showing the functional structure of the control unit.

[0018] Figure 4 It is a side view depicting the head.

[0019] Figure 5 It is a longitudinal sectional view showing the vicinity of the autofocus mechanism.

[0020] Figure 6 This is a bottom view of the light modulation unit.

[0021] Figure 7 This is a conceptual diagram showing the relationship between a plurality of divided modulation regions of a light modulation unit and a plurality of irradiation positions on a substrate.

[0022] Description of reference numerals:

[0023] 1Drawing device

[0024] 5Autofocus mechanism

[0025] 8. Control Unit

[0026] 9 substrates

[0027] 21 stage

[0028] 22 Stage moving mechanism

[0029] 41Description Head

[0030] 43 Illumination optical system

[0031] 44 Light modulation unit

[0032] 45 Projection optical system

[0033] 51 Sensor Department

[0034] 52 Lens moving mechanism

[0035] 91 upper surface (of substrate)

[0036] 93 irradiation positions

[0037] 94 Target area

[0038] 421 Light Source

[0039] 442 Light Modulation Area

[0040] 443 Split Modulation Area

[0041] 451 First lens group

[0042] 452 Second lens group

[0043] 802 drawing control unit

[0044] 803 lens movement control unit DETAILED DESCRIPTION

[0045] Figure 1 1 is a perspective view showing a drawing device 1 according to an embodiment of the present invention. The drawing device 1 is a direct drawing device that draws a pattern by irradiating a photosensitive material on a substrate 9 with light that is spatially modulated and is in the form of a substantially light beam, and scanning the irradiated area of ​​the light on the substrate 9. Figure 1 In the diagram, three mutually orthogonal directions are designated as the X direction, the Y direction, and the Z direction, and are indicated by arrows. Figure 1 In the example shown, the X direction and the Y direction are horizontal directions perpendicular to each other, and the Z direction is a vertical direction (ie, an up-and-down direction). The same is true in other drawings.

[0046] The substrate 9 is, for example, a printed circuit board in a substantially rectangular flat plate shape. On the main surface (hereinafter, also referred to as "upper surface 91") on the (+Z) side of the substrate 9, a resist film formed of a photosensitive material is provided on the copper layer. In the drawing device 1, a circuit pattern is drawn (i.e., formed) on the resist film of the substrate 9. In addition, the type and shape of the substrate 9 can be variously changed.

[0047] The drawing device 1 has a stage 21, a stage moving mechanism 22, an alignment unit 3, a drawing unit 4, and a control unit 8. The stage 21 is a roughly rectangular flat plate-shaped member arranged on the lower side (i.e., the (-Z) side) than the alignment unit 3 and the drawing unit 4. The stage 21 has a substrate holding portion 25 that holds the substrate 9 in a horizontal state from the lower side. The substrate holding portion 25 is, for example, a vacuum chuck that adsorbs and holds the lower surface of the substrate 9. The substrate holding portion 25 may have a structure other than a vacuum chuck, for example, it may be a mechanical chuck. The upper surface 91 of the substrate 9 placed on the substrate holding portion 25 is approximately perpendicular to the Z direction and approximately parallel to the X direction and the Y direction.

[0048] The stage moving mechanism 22 is a moving mechanism that moves the stage 21 relative to the alignment section 3 and the drawing section 4 in the horizontal direction (i.e., a direction roughly parallel to the upper surface 91 of the substrate 9). The stage moving mechanism 22 is installed on the upper surface of the base 11 and is supported by the base 11 from the bottom. The stage moving mechanism 22 has a first moving mechanism 23 and a second moving mechanism 24. The second moving mechanism 24 supports the stage 21 from the bottom and moves the stage 21 linearly in the X direction along the guide rail. The first moving mechanism 23 supports the second moving mechanism 24 from the bottom and moves the stage 21 linearly in the Y direction along the guide rail together with the second moving mechanism 24. The driving sources of the first moving mechanism 23 and the second moving mechanism 24 are, for example, a linear servo motor or a device in which a motor is mounted on a ball screw. The structures of the first moving mechanism 23 and the second moving mechanism 24 can be changed in various ways.

[0049] In the drawing device 1, a stage rotating mechanism that rotates the stage 21 around a rotation axis extending in the Z direction may be provided. In addition, a stage lifting mechanism that moves the stage 21 in the Z direction may be provided in the drawing device 1. As the stage rotating mechanism, for example, a servo motor may be used. As the stage lifting mechanism, for example, a linear servo motor may be used. The structures of the stage rotating mechanism and the stage lifting mechanism may be modified in various ways.

[0050] The alignment unit 3 has a plurality of alignment cameras 31. Figure 1 In the example shown, two alignment cameras 31 are arranged in the X direction, but only the alignment camera 31 on the (+X) side is shown. Each alignment camera 31 is supported above the stage 21 and the stage moving mechanism 22 by a support portion 27 provided across the stage 21 and the stage moving mechanism 22. The support portion 27 is, for example, a single metal member provided at one position in the Y direction. Figure 1 In the illustrated example, the support portion 27 is a gate-shaped member (so-called gantry) that spans the stage 21 and the stage moving mechanism 22 , and is provided upright on the upper surface of the base 11 .

[0051] exist Figure 1 In the example shown, two alignment cameras 31 are mounted on the side surface of the (+Y) side of the support portion 27. For example, one of the two alignment cameras 31 is fixed to the support portion 27, and the other alignment camera 31 can be moved in the X direction on the support portion 27. Thus, the distance in the X direction between the two alignment cameras 31 can be changed. In addition, the number of alignment cameras 31 of the alignment portion 3 may be one, or may be three or more.

[0052] Each alignment camera 31 captures an alignment mark (not shown) pre-set on the upper surface 91 of the substrate 9. In the drawing device 1, the substrate 9 is aligned (i.e., the relative position of the substrate 9 with respect to the drawing head 41 is corrected) based on the image of the alignment mark acquired by the alignment camera 31.

[0053] The drawing unit 4 has a plurality of (in Figure 1 In the example shown, there are six drawing heads 41. The plurality of drawing heads 41 have substantially the same structure. Each drawing head 41 has a light modulator that irradiates modulated (i.e., spatially modulated) light downward. Each drawing head 41 is supported by the support portion 27 above the stage 21 and the stage moving mechanism 22. Figure 1 In the example shown, six drawing heads 41 are attached to the side surface on the (-Y) side of the support portion 27. In addition, the alignment camera 31 may be supported by a support portion different from the support portion 27 to which the drawing heads 41 are attached.

[0054] exist Figure 1 In the example shown, six drawing heads 41 are arranged in a substantially straight line substantially parallel to the X direction. The positions of the six drawing heads 41 in the Y direction and the Z direction are substantially the same. Figure 1 , the illustration of the sensor unit 51 described later of each drawing head 41 is omitted. In addition, the plurality of drawing heads 41 do not necessarily need to be arranged in a straight line, and may be arranged in a staggered manner, for example. When the drawing heads 41 are arranged in a staggered manner, for example, the plurality of drawing heads 41 are arranged substantially parallel to the X direction at a first position in the Y direction, and at a second position adjacent to the (-Y) side of the first position, the drawing heads 41 are arranged between the plurality of drawing heads 41 in the X direction. In addition, in the drawing unit 4, the number of drawing heads 41 may be one, or may be two or more.

[0055] In the drawing device 1, the pattern drawing of the substrate 9 is performed in a so-called multi-path manner. Specifically, modulated light is irradiated onto the upper surface 91 of the substrate 9 from the plurality of drawing heads 41 of the drawing unit 4, and the substrate 9 is moved in the Y direction and passes under the drawing heads 41 by the first moving mechanism 23 of the stage moving mechanism 22. Thus, the irradiation area of ​​the light from the plurality of drawing heads 41 is scanned in the Y direction on the substrate 9, thereby drawing the substrate 9. On the substrate 9, a plurality of drawing areas corresponding to the plurality of drawing heads 41 are drawn. Each drawing area is a roughly rectangular strip-shaped area (so-called swath) extending roughly parallel to the Y direction, and the plurality of drawing areas are separated from each other and arranged in the X direction. The area between the plurality of drawing areas in the X direction is a predetermined undrawn drawing area to be drawn later.

[0056] Next, the second moving mechanism 24 is used to step the substrate 9 in the X direction by a predetermined distance. In other words, the substrate 9 is displaced by a predetermined distance in the X direction relative to the drawing head 41. As a result, each drawing head 41 is located at a position corresponding to an undrawn drawing area (for example, above a predetermined drawing area to be drawn next), and the undrawn drawing area is adjacent to the already drawn drawing area drawn by each drawing head 41. Then, the substrate 9 is moved in the Y direction by the first moving mechanism 23 again, and light is irradiated from the drawing head 41 to the substrate 9 in parallel with the movement, and the undrawn drawing area is drawn. In the drawing device 1, the irradiation of light to the substrate 9 moving in the Y direction and the stepping movement of the substrate 9 in the X direction are repeated alternately, thereby drawing a predetermined pattern on the substrate 9.

[0057] In the following description, the Y direction is also referred to as the "main scanning direction" or "scanning direction", and the X direction is referred to as the "sub-scanning direction". The main scanning direction and the sub-scanning direction are directions substantially parallel to the upper surface 91 of the substrate 9. In the stage moving mechanism 22, the first moving mechanism 23 is a main scanning mechanism that moves the stage 21 relative to the drawing head 41 in the main scanning direction. The second moving mechanism 24 is a sub-scanning mechanism that moves the stage 21 relative to the drawing head 41 in the sub-scanning direction.

[0058] In addition, in the drawing device 1, the drawing on the substrate 9 may be performed in a single path method (also referred to as a one-way method) in which the drawing of the pattern on the substrate 9 is completed by moving the substrate 9 only once relative to the drawing head 41 in the Y direction. In this case, when drawing the pattern, the sub-scanning (i.e., the stepping movement in the X direction) of the substrate 9 by the second moving mechanism 24 is not performed. That is, the stage moving mechanism 22 is a scanning mechanism that moves the stage 21 at least in the scanning direction relative to the drawing head 41.

[0059] The control unit 8 controls the structures such as the stage 21 , the stage moving mechanism 22 , the alignment unit 3 , and the drawing unit 4 . Figure 2 8 is a diagram showing the structure of the control unit 8. The control unit 8 has a general computer system structure including a CPU 81, a ROM 82, a RAM 83, a fixed disk 84, a display 85, an input unit 86, a reading device 87, a communication unit 88, and a bus 80. The CPU 81 performs various calculations. The ROM 82 stores basic programs. The RAM 83 stores various information. The fixed disk 84 stores information. The display 85 is a display unit that displays various information such as images. The input unit 86 has a keyboard 86a and a mouse 86b that receive input from the operator.

[0060] The reading device 87 reads information from a computer-readable recording medium 811 such as an optical disk, a magnetic disk, a magneto-optical disk, or a memory card. The display 85, the keyboard 86a, the mouse 86b, and the reading device 87 are connected to the bus 80 via the interface I / F. The communication unit 88 sends and receives signals between the components of the drawing device 1 other than the control unit 8 and external devices. The bus 80 is a signal circuit that connects the CPU 81, the ROM 82, the RAM 83, the fixed disk 84, the display 85, the input unit 86, the reading device 87, and the communication unit 88.

[0061] In the control unit 8, the program 812 is read from the recording medium 811 in advance via the reading device 87 and stored in the fixed disk 84. The program 812 may also be stored in the fixed disk 84 via a network. The CPU 81 functions as a calculation unit that performs calculation processing according to the program 812 and uses the RAM 83 and the fixed disk 84. In addition to the CPU 81, other structures that function as a calculation unit may also be adopted.

[0062] Figure 3 8 is a diagram showing a functional structure realized by the control unit 8 executing arithmetic processing according to a program 812. These functional structures include a storage unit 801, a drawing control unit 802, and a lens movement control unit 803. All or part of these functions can be realized by a dedicated circuit. In addition, these functions can be realized by a plurality of computers. Figure 3 In the functional configuration shown, the drawing control unit 802 and the lens shift control unit 803 are realized by the CPU 81 , the ROM 82 , the RAM 83 , the fixed disk 84 , and their peripheral components. The storage unit 801 is mainly realized by the RAM 83 and the fixed disk 84 .

[0063] Figure 4 This is a side view of one drawing head 41 enlarged and viewed from the (+X) side. The other drawing heads 41 also have the same Figure 4 The drawing head 41 has the same structure as the drawing head 41 shown in the figure. The drawing head 41 includes a light source unit 42, an illumination optical system 43, a light modulation unit 44, a projection optical system 45, a drawing head cover 46, a frame 47, and an autofocus mechanism 5. The light source unit 42, the illumination optical system 43, the light modulation unit 44, the projection optical system 45, and the frame 47 are housed inside the drawing head cover 46. In addition, a part of the autofocus mechanism 5 is also housed inside the drawing head cover 46. Figure 4 In order to facilitate understanding of the drawings, the cross section of the head cover 46 is represented by a dotted line, and the internal structure of the head cover 46 is represented by a solid line. Figure 4 In FIG. 1 , the support portion 27 is also shown.

[0064] exist Figure 4In the example shown, the drawing head cover 46 is a substantially L-shaped member in a side view. The light source unit 42 is arranged inside the drawing head cover 46 at the end portion on the (+Y) side of the upper portion of the drawing head 41. The light source unit 42 has a light source 421 such as an LED (light emitting diode) or an LD (laser diode). Light emitted from the light source 421 is incident on the illumination optical system 43 along a predetermined optical axis J1 of the drawing head 41. Figure 4 In FIG. 1 , the optical axis J1 is depicted by a single-dot chain line.

[0065] The illumination optical system 43 is disposed inside the drawing head cover 46 at the upper part of the drawing head 41, on the (-Y) side of the light source unit 42. The illumination optical system 43 extends substantially parallel to the Y direction. The illumination optical system 43 has optical elements such as a plurality of lenses arranged substantially parallel to the Y direction. Figure 4 In FIG. 4 , the illustration of the plurality of lenses and the like is omitted, and the lens barrel and the like that accommodate the plurality of lenses and the like are illustrated. The illumination optical system 43 guides the light incident from the light source 421 to the light modulation unit 44. Figure 4 In the illustrated example, light that has passed through the illumination optical system 43 enters the light modulation unit 44 via the reflection mirrors 431 and 432 .

[0066] The light modulator 44 is arranged inside the drawing head cover 46 at the end of the (-Y) side of the upper part of the drawing head 41. The light modulator 44 is located on the (-Y) side of the illumination optical system 43. The light modulator 44 has a spatial light modulator that modulates light. The spatial light modulator is, for example, a DMD (Digital Micromirror Device) in which a plurality of micro mirrors are arranged two-dimensionally. In addition, the light modulator 44 may also have a spatial light modulator other than the DMD. The light modulator 44 modulates the light guided by the illumination optical system 43 and guides it to the projection optical system 45.

[0067] The projection optical system 45 is arranged inside the drawing head cover 46 at the end of the drawing head 41 on the (-Y) side, on the (-Z) side (i.e., below) of the light modulation unit 44. The projection optical system 45 extends approximately parallel to the Z direction. The projection optical system 45 has optical elements such as a plurality of lenses arranged approximately parallel to the Z direction. Figure 4 In the figure, the illustration of the plurality of lenses and the like is omitted, and the lens barrel and the like that accommodate the plurality of lenses and the like are shown. The projection optical system 45 projects the light modulated by the light modulating unit 44 onto the upper surface 91 (refer to Figure 1 )guide.

[0068] The projection optical system 45 has a first lens group 451 and a second lens group 452. The first lens group 451 has an optical element such as a plurality of lenses arranged substantially parallel to the Z direction. The second lens group 452 has an optical element such as a single lens, or an optical element such as a plurality of lenses arranged substantially parallel to the Z direction. Figure 4 , for each of the first lens group 451 and the second lens group 452, the illustration of the plurality of lenses and the like is omitted, and the lens barrel and the like that accommodate the plurality of lenses and the like are illustrated. The first lens group 451 and the second lens group 452 are arranged substantially parallel to the Z direction. The first lens group 451 is located on the (+Z) side of the second lens group 452.

[0069] In the projection optical system 45 , the light modulated by the light modulator 44 enters the first lens group 451 and is guided by the first lens group 451 to the second lens group 452 . The second lens group 452 guides the light guided by the first lens group 451 to the upper surface 91 of the substrate 9 .

[0070] The first lens group 451 and the second lens group 452 are mounted on the side surface of the (-Y) side of the frame 47, which is a roughly quadrangular prism-shaped member extending in the Z direction. The first lens group 451 and the second lens group 452 are mounted on the frame 47 in a manner that allows them to move in the Z direction. The first lens group 451 is raised and lowered when the magnification of the image formed on the substrate 9 is changed, and is not raised and lowered during the pattern drawing on the substrate 9. The second lens group 452 is raised and lowered by the autofocus mechanism 5 during the pattern drawing on the substrate 9. The frame 47 is a supporting member that supports the first lens group 451 and the second lens group 452. The frame 47 is fixed to the inner side of the drawing head cover 46, for example, and is indirectly supported by the support portion 27 via the drawing head cover 46. The frame 47 may be a part of the drawing head cover 46.

[0071] In the drawing head 41, the focus position of the light emitted from the drawing head 41 to the substrate 9 is adjusted in the Z direction by moving the second lens group 452 in the Z direction in the projection optical system 45. The focus position is a position where the light emitted from the drawing head 41 to the substrate 9 is focused on the (-Z) side of the drawing head 41. In other words, the focus position is a position where the light passing through the second lens group 452 from the (+Z) side to the (-Z) side is focused on the (-Z) side of the second lens group 452. In other words, the focus position is a position where the image of the micromirror of the DMD of the light modulation unit 44 is formed on the (-Z) side of the second lens group 452.

[0072] In the projection optical system 45, the first lens group 451 is accommodated inside the drawing head cover 46. In addition, the second lens group 452 is also accommodated inside the drawing head cover 46. The lower end of the drawing head cover 46 is open. The lower end of the second lens group 452 (that is, the lower end of the projection optical system 45) can protrude downward from the lower end opening of the drawing head cover 46.

[0073] The autofocus mechanism 5 is arranged near the second lens group 452 of the projection optical system 45. The autofocus mechanism 5 moves the second lens group 452 in the Z direction (i.e., moves up and down) according to the change of the distance between the projection optical system 45 and the substrate 9, thereby adjusting the focus position of the light emitted from the drawing head 41 to the substrate 9 in the Z direction.

[0074] Figure 5 It is a magnified representation Figure 4 The drawing head 41 shown is a longitudinal sectional view of the second lens group 452 of the projection optical system 45 and the vicinity of the autofocus mechanism 5. Figure 5 In FIG. 1 , a part of the structure is shown on the side. Figure 5 In the figure, the structure closer to the inside than the cross section is also shown with thin lines.

[0075] The autofocus mechanism 5 includes a sensor unit 51 and a lens shift mechanism 52. The sensor unit 51 is mounted on the second lens group 452 of the projection optical system 45. Specifically, the sensor unit 51 is fixed to the lower end of the lens barrel of the second lens group 452 (i.e., the end on the (-Z) side). The sensor unit 51 measures the distance between the lower end of the second lens group 452 and the stage 21 (see Figure 1 ) in the Z direction between the upper surface 91 of the substrate 9 on which the projection distance is measured (hereinafter referred to as the “projection distance”).

[0076] The sensor unit 51 includes a light emitting unit 511, a light receiving unit 512, and a sensor support unit 513. The sensor support unit 513 is, for example, a substantially cylindrical member extending substantially parallel to the Z direction. The sensor support unit 513 is located on the (-Z) side of the second lens group 452 outside the drawing head cover 46 and is fixed to the lower end of the lens barrel of the second lens group 452. Figure 5 In the example shown, the end of the light emitting unit 511 on the (-Z) side of the sensor support unit 513 is fixed to the end of the (+Y) side of the sensor support unit 513. In addition, the end of the light receiving unit 512 on the (-Z) side of the sensor support unit 513 is fixed to the end of the (-Y) side of the sensor support unit 513. Light emitted from the light emitting unit 511 to the (-Y) side and the (-Z) side is reflected by the upper surface 91 of the substrate 9 and received by the light receiving unit 512. The light receiving unit 512 is, for example, a line sensor. In the sensor unit 51, the above-mentioned projection distance is obtained based on the light receiving position in the light receiving unit 512 of the reflected light from the substrate 9.

[0077] The lens moving mechanism 52 is mounted on the frame 47 and supported by the frame 47. The lens moving mechanism 52 connects the second lens group 452 and the frame 47. The lens moving mechanism 52 supports the second lens group 452 and moves the second lens group 452 in the Z direction. The lens moving mechanism 52 has a driving portion 521, a guide rail 522, a bearing seat 523, and a lens supporting portion 524.

[0078] The guide rail 522 is fixed to the side surface of the (-Y) side of the frame 47 on the (+Y) side of the second lens group 452. When the Y direction is referred to as the "lateral direction", the guide rail 522 is arranged between the second lens group 452 and the frame 47 in the lateral direction. The guide rail 522 has two rails arranged in the X direction. The two rails extend substantially parallel to the Z direction.

[0079] The bearing seat 523 is a bearing member connected to the guide rail 522 from the (-Y) side and is movable in the Z direction along the guide rail 522. Figure 5 In the example shown, two bearing seats 523 are respectively connected to two rails of the guide rail 522. Each bearing seat 523 is, for example, a substantially rectangular parallelepiped or substantially flat plate-shaped member. Each bearing seat 523 contacts the guide rail 522 and moves smoothly along the guide rail 522 in the Z direction.

[0080] The lens support part 524 is a member fixed to the bearing seat 523 and supports the second lens group 452. The lens support part 524 is fixed to the (-Y) side surface of the bearing seat 523. The second lens group 452 supported by the lens support part 524 is indirectly fixed to the bearing seat 523 via the lens support part 524.

[0081] The portion on the (+Y) side of the lens support 524 is inserted into the interior of the frame 47 from the opening 471 provided between the two rails of the guide rail 522 on the side surface on the (-Y) side of the frame 47. This portion is connected to the driving portion 521 inside the frame 47. The weight of the lens support 524 and the second lens group 452 is mainly supported by the driving portion 521.

[0082] The driving unit 521 extends along the Z direction inside the frame 47 and is fixed to the frame 47. In other words, the driving unit 521 is supported by the support unit 27 via the frame 47. The driving unit 521 is, for example, a combination of an electric motor and a ball screw. The portion on the (+Y) side of the above-mentioned lens support unit 524 is fixed to a movable member that can move in the Z direction in the driving unit 521. In the driving unit 521, when the movable member moves in the Z direction, the lens support unit 524 fixed to the movable member, and the second lens group 452 and the bearing seat 523 fixed to the lens support unit 524 move in the Z direction while being guided by the guide rail 522. In addition, the driving unit 521 can be changed to various forms such as a linear servo motor and a cylinder.

[0083] exist Figure 1 In the drawing device 1 shown in the figure, when the above-mentioned pattern drawing is performed on the substrate 9, the drawing control unit 802 controls the drawing control unit 802 based on the storage unit 801 (refer to Figure 3 ) is used to control the light modulation unit 44 and the stage moving mechanism 22, thereby irradiating the modulated light onto the upper surface 91 of the substrate 9 moving in the Y direction to draw the pattern.

[0084] In the drawing of the above-mentioned pattern by the drawing device 1, so-called multiple exposure is performed under the control of the drawing control unit 802. Specifically, Figure 6 As shown, the DMD 441 as the spatial light modulator of the light modulation unit 44 has a light modulation area 442 in which a plurality of micro mirrors are arranged two-dimensionally, and the light modulation area 442 includes a plurality of divided modulation areas 443 arranged in a predetermined direction. Figure 6 In the example shown, four divided modulation areas 443 are provided in the light modulation area 442. Figure 6 In FIG. 4 , each divided modulation area 443 is surrounded by a thick line. Figure 6 In the figure, for the convenience of illustration, each micro-mirror is represented by a square larger than the actual size, and the number of plural micro-mirrors is drawn smaller than the actual number.

[0085] Each divided modulation area 443 is connected to an adjacent divided modulation area 443, and no micro-mirror is arranged between each two adjacent divided modulation areas 443. The arrangement direction of the plurality of divided modulation areas 443 in the DMD 441 is a direction corresponding to the above-mentioned scanning direction (i.e., the Y direction) on the substrate 9. Figure 6 In the example shown, the four divided modulation areas 443 are arranged substantially parallel to the Y direction.

[0086] Figure 7This is a diagram conceptually showing the relationship between the plurality of divided modulation areas 443 of the light modulation unit 44 and the plurality of irradiation positions 93 on the substrate 9 that are irradiated by the light reflected by the plurality of divided modulation areas 443. Each irradiation position 93 is a region where an image is formed by focusing the light reflected by one of the divided modulation areas 443 corresponding to the irradiation position 93. Figure 7 In the embodiment, the four irradiation positions 93 are arranged substantially parallel to the Y direction. The first, second, third, and fourth irradiation positions 93 from the (+Y) side correspond to the first, second, third, and fourth segmented modulation regions 443 from the (+Y) side, respectively. Figure 7 In FIG. 4 , the corresponding divided modulation area 443 and the irradiation position 93 are connected by arrows.

[0087] In the drawing device 1, the substrate 9 moves in the (-Y) direction, and when an area 94 (hereinafter, also referred to as "target area 94") on the upper surface 91 of the substrate 9 is located at the first irradiation position 93 from the (+Y) side, the target area 94 is irradiated with light having an irradiation area of ​​a predetermined shape by using the first divided modulation area 443 from the (+Y) side controlled by the drawing control unit 802, thereby forming an image of a predetermined shape (that is, an image of a pattern element constituting a part of the pattern). In addition, when the substrate 9 further moves in the (-Y) direction and the target area 94 is located at the second irradiation position 93 from the (+Y) side, the target area 94 is irradiated with light having an irradiation area of ​​the same shape as the above-mentioned irradiation area by using the second divided modulation area 443 from the (+Y) side controlled by the drawing control unit 802, thereby forming an image of the same shape as the above-mentioned image.

[0088] Similarly, when the target area 94 of the substrate 9 is located at the third irradiation position 93 from the (+Y) side, an image having the same shape as the above image is formed in the target area 94 by using the third divided modulation area 443 from the (+Y) side controlled by the drawing control unit 802. In addition, when the target area 94 is located at the fourth irradiation position 93 from the (+Y) side, an image having the same shape as the above image is formed in the target area 94 by using the fourth divided modulation area 443 from the (+Y) side controlled by the drawing control unit 802.

[0089] That is, when the substrate 9 moves in the (-Y) direction and the target area 94 passes through the plurality of irradiation positions 93, the light modulation unit 44 is controlled by the drawing control unit 802, and an image of the same shape is sequentially formed for the target area 94 at each of the plurality of irradiation positions 93. In the target area 94, the photosensitive material is exposed to light by the accumulated light amount formed by forming the image of the same shape a plurality of times (four times in the present embodiment), and the above-mentioned pattern elements are drawn. In the pattern drawing of the substrate 9, in each area on the substrate 9, the pattern elements are drawn by a plurality of exposures (i.e., multiple exposures) in the same manner as the above-mentioned target area 94. In addition, the number of the plurality of divided modulation areas 443 included in the light modulation area 442 is not limited to four, and various changes can be made within a range of two or more.

[0090] In the drawing device 1, while the above-mentioned pattern is being drawn on the substrate 9, the measurement is continuously performed at predetermined time intervals (hereinafter also referred to as "measurement intervals"). Figure 5 The projection distance is measured by the sensor unit 51 as shown. The projection distance measured by the sensor unit 51 is output to the lens shift control unit 803. The lens shift control unit 803 controls the lens shift mechanism 52 based on the output from the sensor unit 51.

[0091] Specifically, the lens movement control unit 803 compares the projection distance measured by the sensor unit 51 (hereinafter, also referred to as "measured projection distance") with the target projection distance as the designed projection distance, and calculates the movement amount of the second lens group 452 in the Z direction (i.e., the movement direction and the movement distance) so that the difference between the measured projection distance and the target projection distance becomes 0. Then, the lens movement control unit 803 sends a drive signal to the drive unit 521 of the lens movement mechanism 52, and the drive unit 521 is driven according to the drive signal. The lens movement control unit 803 sends the drive signal at the above-mentioned measurement interval.

[0092] Thus, the position of the second lens group 452 in the Z direction is adjusted, and the projection distance becomes substantially equal to the target projection distance. In other words, the focus position of the light emitted from the drawing head 41 to the substrate 9 is adjusted in the Z direction and aligned with the upper surface 91 of the substrate 9. As a result, even if the substrate 9 is deformed such as warping or the upper surface 91 of the substrate 9 has unevenness, the focus position can be aligned with the upper surface 91 of the substrate 9, so that high-precision drawing can be achieved.

[0093] In the above control of the lens moving mechanism 52 by the lens moving control unit 803, the driving of the driving unit 521 in the lens moving mechanism 52 is controlled so that the number of times of raising and lowering the second lens group 452 (hereinafter also referred to as "unit movement number") during the period when the above-mentioned target area 94 passes through the four irradiation positions 93 is less than 4. In other words, by controlling the autofocus mechanism 5 by the lens moving control unit 803, the unit movement number is made smaller than the number of the plurality of divided modulation areas 443 in the light modulating unit 44.

[0094] Specifically, the measurement interval of the sensor unit 51 (i.e., the transmission interval of the drive signal to the drive unit 521) is greater than the value obtained by dividing the time required for the target area 94 to pass through the four irradiation positions 93 by the number of the plurality of divided modulation areas 443, i.e., "4". For example, when the length of the four irradiation positions 93 in the Y direction is 8 mm and the moving speed (i.e., scanning speed) of the substrate 9 in the Y direction is 100 mm / second, the measurement interval is set by the lens movement control unit 803 to be greater than 0.02 seconds (i.e., (8 / 100 / 4) seconds).

[0095] In the drawing device 1, even if the second lens group 452 is vibrated (relatively small vibration, hereinafter also referred to as "micro vibration") due to the driving load applied to the driving unit 521 when the second lens group 452 is raised or lowered, as described above, by making the number of unit movements smaller than the number of the plurality of divided modulation areas 443 in the light modulation unit 44, it is possible to prevent the influence of the micro vibration in all of the four exposures for one object area 94. In other words, even if the influence of the micro vibration of the second lens group 452 is assumed in a part of the exposures among the four exposures for one object area 94, it is possible to prevent the influence in the remaining exposures.

[0096] As described above, in the drawing device 1, the drawing of the object area 94 is performed by multiple exposures, and the photosensitive material is exposed to light in the area where the cumulative light amount of the four exposures exceeds a predetermined threshold value. In addition, in the drawing device 1, even if the irradiation area on the substrate 9 is slightly deviated from the designed irradiation area due to the influence of the microvibration of the second lens group 452 in the above-mentioned part of the exposure, the irradiation area is roughly consistent with the designed irradiation area in the above-mentioned other exposures. Therefore, outside the designed irradiation area (that is, the area irradiated by light due to the influence of the microvibration of the second lens group 452), the cumulative light amount of the four exposures becomes less than the above-mentioned threshold value, and the possibility of preventing the photosensitive material from being exposed to light becomes high. As a result, the change of the line width of the pattern caused by the microvibration of the second lens group 452 is suppressed, thereby suppressing the reduction of the drawing accuracy of the pattern.

[0097] In addition, the above-mentioned number of unit movement can be set in various ways as long as it is greater than 0 and less than the number of the plurality of divided modulation areas 443 in the light modulation unit 44 (4 in the above example). For example, the number of unit movement can be an integer or a decimal. From the viewpoint of suppressing the reduction in the drawing accuracy of the above-mentioned pattern, it is preferable to set the number of unit movement to one or less.

[0098] In the drawing head 41, the second lens group 452 can move in the (+Z) direction and the (-Z) direction from a predetermined reference position in the Z direction. In addition, the maximum value of the movement distance of the second lens group 452 in the Z direction from the reference position is limited by the lens movement control unit 803. Thus, even if a relatively deep recess such as a via is formed on the substrate 9, when the projection distance of the sensor unit 51 is measured in the recess, it is possible to prevent the unnecessary movement of the second lens group 452 such as aligning the above-mentioned focus position with the bottom of the recess. Thus, micro vibration of the second lens group 452 caused by unnecessary long-distance movement of the second lens group 452 is prevented, thereby preventing a decrease in drawing accuracy due to the micro vibration.

[0099] In the drawing device 1, the maximum moving distance of the second lens group 452 in the Z direction in a time equal to the above-mentioned measurement interval (hereinafter also referred to as "unit moving time") is twice the above-mentioned maximum value of the moving distance of the second lens group 452 from the reference position. Therefore, the speed and acceleration of the second lens group 452 moving in the Z direction by the driving unit 521 are set so that the movement of the above-mentioned maximum moving distance is completed within the unit moving time. The lens movement control unit 803 limits the maximum speed and / or maximum acceleration of the movement of the second lens group 452 in the Z direction to be as small as possible within the range of completing the movement of the above-mentioned maximum moving distance within the unit moving time. In this way, the above-mentioned micro-vibration that may increase as the speed and acceleration of the second lens group 452 when moving increase can be suppressed. As a result, the reduction in the drawing accuracy of the pattern caused by the micro-vibration is suppressed.

[0100] As described above, the speed and acceleration of the movement of the second lens group 452 in the Z direction are set based on the unit movement time. In addition, as described above, the unit movement time (i.e., the measurement interval) is determined by the length of the plurality of (four in the above example) irradiation positions 93 in the Y direction, the movement speed of the substrate 9 in the Y direction (i.e., the scanning speed), and the number of the plurality of divided modulation areas 443 (i.e., four in the above example). Generally, since the length of the plurality of irradiation positions 93 and the number of the plurality of divided modulation areas 443 are predetermined, the speed and acceleration of the movement of the second lens group 452 in the Z direction are determined based on the scanning speed of the substrate 9. Therefore, the above-mentioned limitation of the maximum speed and / or maximum acceleration of the movement of the second lens group 452 in the Z direction based on the lens movement control unit 803 is performed based on the scanning speed of the substrate 9 (i.e., the speed at which the stage moving mechanism 22 moves the stage 21 in the scanning direction).

[0101] In addition, the scanning speed of the substrate 9 is determined based on the type of photosensitive material on the substrate 9 and the required exposure required for the photosensitization of the photosensitive material. Therefore, the above-mentioned limitation of the maximum speed and / or maximum acceleration of the movement of the second lens group 452 in the Z direction by the lens movement control unit 803 can also be performed based on the type of photosensitive material on the substrate 9 and / or the required exposure of the photosensitive material. Among them, if the scanning speed of the substrate 9, the type of photosensitive material on the substrate 9, and the required exposure of the photosensitive material are referred to as "information related to the scanning speed of the substrate 9", the above-mentioned limitation of the maximum speed and / or maximum acceleration of the movement of the second lens group 452 in the Z direction by the lens movement control unit 803 is performed based on the information related to the scanning speed of the substrate 9 (that is, the information related to the movement speed of the stage 21 in the scanning direction based on the stage moving mechanism 22). In addition, the information related to the scanning speed of the substrate 9 may also include information other than the scanning speed of the substrate 9, the type of photosensitive material on the substrate 9, and the required exposure of the photosensitive material.

[0102] As described above, the drawing device 1 for drawing a pattern by irradiating light onto a substrate includes a stage 21, a drawing head 41, a stage moving mechanism 22, and a control unit 8. The stage 21 holds the substrate 9. The drawing head 41 irradiates modulated light onto the substrate 9. The stage moving mechanism 22 moves the stage 21 relative to the drawing head 41 in a scanning direction (in the above example, the Y direction) parallel to the upper surface 91 of the substrate 9. The control unit 8 controls the drawing head 41. The drawing head 41 includes an illumination optical system 43, a light modulator 44, a projection optical system 45, and an autofocus mechanism 5. Light emitted from a light source 421 is incident on the illumination optical system 43. The light modulator 44 modulates the light guided by the illumination optical system 43. The projection optical system 45 guides the light modulated by the light modulator 44 to the substrate 9. The autofocus mechanism 5 adjusts the focus position of the light emitted from the drawing head 41 according to the change in the distance between the projection optical system 45 and the substrate 9 (i.e., the projection distance).

[0103] The light modulation area 442 of the light modulation unit 44 includes a plurality of divided modulation areas 443 respectively corresponding to the plurality of irradiation positions 93 arranged in the above-mentioned scanning direction below the drawing head 41 (i.e., the (-Z) side). The projection optical system 45 includes a first lens group 451 and a second lens group 452. The light modulated by the light modulation unit 44 is incident on the first lens group 451. The second lens group 452 guides the light guided by the first lens group 451 to the substrate 9. The autofocus mechanism 5 includes a sensor unit 51 and a lens moving mechanism 52. The sensor unit 51 measures the distance between the second lens group 452 and the substrate 9 in the up-down direction (i.e., the Z direction). The lens moving mechanism 52 supports the second lens group 452. The lens moving mechanism 52 moves the second lens group 452 in the up-down direction based on the output from the sensor unit 51, thereby adjusting the above-mentioned focusing position of the light emitted from the drawing head 41.

[0104] The control unit 8 includes a drawing control unit 802 and a lens movement control unit 803. The drawing control unit 802 controls the light modulation unit 44 to sequentially form an image of the same shape for the object area 94 at each of the plurality of irradiation positions 93 when the substrate 9 is moved together with the stage 21 by the stage movement mechanism 22 so that an area on the substrate 9 (i.e., the object area 94) passes through the plurality of irradiation positions 93. The lens movement control unit 803 controls the autofocus mechanism 5 to make the number of unit movements, which is the number of times the second lens group 452 is raised and lowered during the period when the plurality of irradiation positions 93 form the above-mentioned image for the object area 94, less than the number of the plurality of divided modulation areas 443.

[0105] Thus, as described above, the number of times the second lens group 452 is raised and lowered in the drawing based on multiple exposure can be reduced at each position on the substrate 9. Therefore, even if micro vibrations are generated when the second lens group 452 is raised and lowered by the autofocus mechanism 5, changes in the line width of the pattern caused by the micro vibrations can be suppressed, and as a result, a decrease in the drawing accuracy of the pattern can be suppressed.

[0106] As described above, the unit movement number is preferably 1 or less. This can further suppress a decrease in the drawing accuracy of the pattern due to microvibration of the second lens group 452 .

[0107] As described above, preferably, the lens movement control unit 803 limits the maximum moving speed or maximum acceleration of the second lens group 452 by the lens moving mechanism 52 based on information related to the moving speed in the scanning direction of the stage 21 by the stage moving mechanism 22 (i.e., the scanning direction of the substrate 9). As a result, it is possible to suppress the moving speed or acceleration of the second lens group 452 from becoming too large. As a result, it is possible to further suppress the reduction in the drawing accuracy of the pattern caused by the microvibration of the second lens group 452.

[0108] In the drawing device 1, the drawing of the pattern on the substrate 9 does not necessarily need to be performed by the above-mentioned multiple exposure. For example, in the drawing device 1, the above-mentioned pattern can also be drawn on the substrate 9 by irradiating each position on the substrate 9 with light modulated by the light modulation unit 44 only once.

[0109] In this case, a drawing device 1 for drawing a pattern by irradiating light onto a substrate 9 includes a stage 21, a drawing head 41, and a stage moving mechanism 22. The stage 21 holds the substrate 9. The drawing head 41 irradiates modulated light onto the substrate 9. The stage moving mechanism 22 moves the stage 21 relative to the drawing head 41 in a scanning direction (in the above example, the Y direction) parallel to the upper surface 91 of the substrate 9. The drawing head 41 includes an illumination optical system 43, a light modulation unit 44, a projection optical system 45, and an automatic focusing mechanism 5. Light emitted from a light source 421 is incident on the illumination optical system 43. The light modulation unit 44 modulates the light guided by the illumination optical system 43. The projection optical system 45 guides the light modulated by the light modulation unit 44 to the substrate 9. The automatic focusing mechanism 5 adjusts the focus position of the light emitted from the drawing head 41 according to the change in the distance between the projection optical system 45 and the substrate 9 (i.e., the projection distance).

[0110] The projection optical system 45 includes a first lens group 451 and a second lens group 452. The light modulated by the light modulation unit 44 is incident on the first lens group 451. The second lens group 452 guides the light guided by the first lens group 451 to the substrate 9. The autofocus mechanism 5 includes a sensor unit 51 and a lens shift mechanism 52. The sensor unit 51 measures the distance between the second lens group 452 and the substrate 9 in the up-down direction (i.e., the Z direction). The lens shift mechanism 52 supports the second lens group 452. The lens shift mechanism 52 moves the second lens group 452 in the up-down direction based on the output from the sensor unit 51, thereby adjusting the above-mentioned focus position of the light emitted from the drawing head 41.

[0111] In the drawing device 1, the maximum moving speed or the maximum acceleration of the second lens group 452 by the lens moving mechanism 52 is limited based on the information related to the moving speed of the stage 21 in the scanning direction by the stage moving mechanism 22 (that is, the moving speed of the substrate 9). As a result, it is possible to suppress the moving speed or the acceleration of the second lens group 452 from becoming too large. As a result, it is possible to suppress the reduction in the drawing accuracy of the pattern due to the microvibration of the second lens group 452.

[0112] In the drawing device 1, when drawing using the above-mentioned multi-path method is performed, it is preferable that the maximum moving speed or maximum acceleration of the second lens group 452 by the lens moving mechanism 52 is limited based on the maximum value of the vertical movement distance of the second lens group 452 when drawing the first path (that is, when the substrate 9 is moved in the Y direction for the first time while being irradiated with light from the drawing head 41) in addition to the information related to the scanning speed of the substrate 9. Alternatively, the maximum moving speed or maximum acceleration of the second lens group 452 may be limited based on the maximum value of the vertical movement distance of the second lens group 452 when drawing any path after the second path instead of when drawing the first path. That is, it is preferable that the maximum moving speed or maximum acceleration of the second lens group 452 is limited based on the maximum value of the vertical movement distance of the second lens group 452 when drawing a representative path in addition to the information related to the scanning speed of the substrate 9.

[0113] In this case, the stage moving mechanism 22 can also move the stage 21 relative to the drawing head 41 in the sub-scanning direction (in the above example, the X direction) parallel to the upper surface 91 of the substrate 9 and perpendicular to the scanning direction. In the drawing device 1, the following process is repeatedly performed to draw a predetermined pattern on the substrate 9: the substrate 9 is relatively moved in the scanning direction (in the above example, the Y direction) in a state where the substrate 9 is irradiated with modulated light from one drawing head 41, and one of the plurality of drawing areas arranged in the sub-scanning direction is drawn, and after the drawing of the one drawing area is completed, the substrate 9 is relatively displaced by a predetermined distance in the sub-scanning direction relative to the drawing head 41, so that the drawing head 41 is located at a position corresponding to an undrawn drawing area adjacent to the one drawing area among the plurality of drawing areas. In addition, the maximum moving speed or maximum acceleration of the second lens group 452 by the lens moving mechanism 52 is also limited according to the maximum moving distance of the second lens group 452 in the vertical direction when drawing the one drawing area.

[0114] In this way, when the substrate 9 is drawn using the multi-path method, the maximum moving speed or maximum acceleration of the second lens group 452 is limited based on the actual autofocus result when drawing a representative path, thereby further suppressing the moving speed or acceleration of the second lens group 452 from becoming too large. As a result, the reduction in the drawing accuracy of the pattern caused by the microvibration of the second lens group 452 can be further suppressed.

[0115] The above-described drawing device 1 can be modified in various ways.

[0116] For example, the unit movement times of the second lens group 452 may be greater than one.

[0117] In the drawing device 1, the maximum moving speed or maximum acceleration of the second lens group 452 does not necessarily need to be limited based on the maximum moving distance of the second lens group 452 in the vertical direction when drawing the above-mentioned one drawing area. In addition, the maximum moving speed or maximum acceleration of the second lens group 452 does not necessarily need to be limited based on information related to the scanning speed of the substrate 9.

[0118] The shape of the drawing head cover 46 can be variously changed, and for example, the drawing head cover 46 may be a member extending substantially parallel to the Z direction. In this case, the illumination optical system 43 and the light source unit 42 are arranged on the (+Z) side of the light modulation unit 44, for example.

[0119] exist Figure 4In the example shown, one light source 421 is depicted in the light source unit 42, but the number of light sources 421 provided in the light source unit 42 may be plural. For example, a plurality of light sources 421 emitting light of different wavelengths may be provided in the light source unit 42. In this case, when a pattern is depicted on the substrate 9, one or more than two light sources 421 of the plurality of light sources 421 are selected and used according to the type of photosensitive material on the substrate 9, etc. In addition, the light source 421 provided in the light source unit 42 is not limited to LED and LD, and various types of light sources may be used. In addition, the light source unit 42 may also be provided outside the drawing head 41. In this case, the light emitted from the light source unit 42 is guided to the drawing head 41 via an optical fiber or the like.

[0120] The stage moving mechanism 22 does not necessarily need to move the stage 21 , and for example, may move the plurality of drawing heads 41 in a direction parallel to the upper surface 91 of the substrate 9 above the fixed stage 21 .

[0121] The substrate 9 to be drawn in the drawing device 1 is not necessarily limited to a printed wiring board. In the drawing device 1, for example, a circuit pattern may be drawn on a semiconductor substrate, a glass substrate for a flat panel display device such as a liquid crystal display device or a plasma display device, a glass substrate for a photomask, a substrate for a solar cell panel, or the like.

[0122] The configurations in the above-described embodiment and various modifications may be appropriately combined as long as they do not contradict each other.

[0123] Although the present invention has been described and illustrated in detail, the foregoing description is illustrative rather than restrictive. Therefore, it can be said that many modifications and ways are possible without departing from the scope of the present invention.

Claims

1. A drawing device for drawing a pattern by irradiating light onto a substrate, wherein: have: a stage, holding the substrate; a drawing head for irradiating modulated light to the substrate; a stage moving mechanism for moving the stage relative to the drawing head in a scanning direction parallel to the upper surface of the substrate; and A control unit controls the drawing head. The drawing head has: An illumination optical system, incident with light emitted from a light source; a light modulation unit that modulates the light guided by the illumination optical system; a projection optical system that guides the light modulated by the light modulator toward a substrate; and an automatic focusing mechanism for adjusting a focus position of light emitted from the drawing head according to a change in the distance between the projection optical system and the substrate, The light modulation area of ​​the light modulation unit includes a plurality of divided modulation areas corresponding to a plurality of irradiation positions arranged along the scanning direction below the drawing head, respectively. The projection optical system comprises: A first lens group, into which the light modulated by the light modulating unit is incident; as well as a second lens group, directing the light directed by the first lens group toward the substrate, The automatic focusing mechanism comprises: A sensor unit for measuring a distance between the second lens group and the substrate in a vertical direction; as well as a lens moving mechanism that supports the second lens group and moves the second lens group in the up-down direction based on the output from the sensor unit to adjust the focus position of the light emitted from the drawing head, The control unit has: a drawing control unit that controls the light modulation unit to sequentially form an image of the same shape for the one region at each of the plurality of irradiation positions when the substrate and the stage are moved together by the stage moving mechanism so that an area on the substrate passes through the plurality of irradiation positions; as well as The lens movement control unit controls the autofocus mechanism so that the number of unit movements is less than the number of the plurality of divided modulation areas. The number of unit movements is the number of times the second lens group is raised and lowered during the period when the image of the one area is formed at the plurality of irradiation positions.

2. The drawing device according to claim 1, wherein: The unit moves once or less.

3. The drawing device according to claim 1 or 2, wherein: The lens movement control unit limits a maximum moving speed or a maximum acceleration of the second lens group by the lens moving mechanism based on information on a moving speed of the stage in the scanning direction by the stage moving mechanism.

4. A drawing device for drawing a pattern by irradiating light onto a substrate, wherein: have: a stage, holding the substrate; a drawing head for irradiating modulated light to the substrate; as well as a stage moving mechanism for moving the stage relative to the drawing head in a scanning direction parallel to the upper surface of the substrate, The drawing head has: An illumination optical system, incident with light emitted from a light source; a light modulation unit that modulates the light guided by the illumination optical system; a projection optical system that guides the light modulated by the light modulator toward a substrate; and an automatic focusing mechanism for adjusting a focus position of light emitted from the drawing head according to a change in the distance between the projection optical system and the substrate, The projection optical system comprises: A first lens group, into which the light modulated by the light modulating unit is incident; as well as a second lens group, directing the light directed by the first lens group toward the substrate, The automatic focusing mechanism comprises: A sensor unit for measuring a distance between the second lens group and the substrate in a vertical direction; as well as a lens moving mechanism that supports the second lens group and moves the second lens group in a vertical direction based on an output from the sensor section, thereby adjusting the focus position of the light emitted from the drawing head; Based on information on the moving speed of the stage in the scanning direction by the stage moving mechanism, a maximum moving speed or a maximum acceleration of the second lens group by the lens moving mechanism is limited.

5. The drawing device according to claim 4, wherein: The stage moving mechanism can also move the stage relative to the drawing head in a sub-scanning direction parallel to the upper surface of the substrate and perpendicular to the scanning direction. In the drawing device, the following processing is repeatedly performed to draw a predetermined pattern on the substrate: by relatively moving the substrate in the scanning direction while irradiating the substrate with modulated light from the drawing head, one of a plurality of drawing areas arranged in the sub-scanning direction is drawn; after the drawing of the one drawing area is completed, the drawing head is positioned at a position corresponding to an undrawn drawing area adjacent to the one drawing area among the plurality of drawing areas by relatively displacing the substrate by a predetermined distance in the sub-scanning direction with respect to the drawing head; The maximum moving speed or the maximum acceleration of the second lens group by the lens shift mechanism is further limited according to the maximum value of the vertical moving distance of the second lens group when drawing the one drawing area.

Images