Lithography system

Abstract

To appropriately hold a plurality of types of substrates in a lithography system.SOLUTION: A lithography system that draws a pattern on a substrate by irradiation of light includes: a holding part 25 that holds the substrate by sucking air from a plurality of suction holes; a decompression part 8 that generates power by which the holding part 25 sucks air; a storage part 62 that stores the plurality of types of the substrates; and a suction control part 61 that controls the power by which the holding part 25 sucks the substrate by changing a set value of an operation of the decompression part 8 according to the type of the substrate.SELECTED DRAWING: Figure 7

Description

[Technical field]

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

[0002] Conventionally, when drawing a pattern on a printed circuit board, a semiconductor board, or the like (hereinafter referred to as a "board"), a drawing device is used that draws a pattern on a photosensitive material formed on the board by irradiating the photosensitive material with light. Some of these drawing devices hold the board by sucking air through a suction hole provided in a holding part.

[0003] For example, in the exposure apparatus (drawing apparatus) disclosed in Patent Document 1, a work chuck that holds a substrate holds the substrate by vacuum suction. The work chuck has a central suction area, an annular suction area surrounding the central suction area, and three suction areas located outside the annular suction area. Each suction area is partitioned by a partition wall and a peripheral wall. Each suction area has multiple protrusions that are the same height as the partition wall. In order to suppress bending of the substrate, an air regulator connected to each suction area is adjusted according to the area of ​​the corresponding suction area, thereby making the pressure in each suction area approximately constant. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] JP 2011-191755 A Summary of the Invention [Problem to be solved by the invention]

[0005] However, when a drawing device is capable of holding a plurality of different types of substrates, the substrates have different sizes and different positions of holes depending on the type. Therefore, if the substrate is simply sucked and held, the suction force differs depending on the type of substrate, and the change in the contact state between the substrate and the holder from the start of suction to the end of suction and the contact state after suction differ depending on the type. As a result, when holding a substrate of a specific type, suction may have an undesirable effect on the substrate.

[0006] The present invention has been made in consideration of the above-mentioned problems, and has an object to appropriately hold a plurality of types of substrates in a drawing apparatus. [Means for solving the problem]

[0007] A first aspect of the present invention is a drawing device that draws a pattern on a substrate by irradiating light, and includes a holding unit that holds the substrate by sucking air through a plurality of suction holes, a pressure reduction unit connected to the holding unit and generating a force for the holding unit to suck air, a memory unit that stores a plurality of substrate types, a suction adjustment unit that reads and inputs the type of substrate that the holding unit is to hold from the memory unit and adjusts the force with which the holding unit suctions the substrate by changing a setting value for the operation of the pressure reduction unit in accordance with the type of substrate, and a light irradiation unit that draws a pattern on the substrate by emitting light toward the substrate held by the holding unit.

[0008] A second aspect of the present invention is the drawing apparatus of the first aspect, wherein the holder is capable of holding the substrate by selectively sucking air from the plurality of suction holes in accordance with the size of the substrate.

[0009] A third aspect of the present invention is the drawing apparatus of the first aspect (which may be either the first or second aspect), wherein the substrate held by the holder has resist layers on both sides.

[0010] A fourth aspect of the present invention is the drawing device of the first aspect (which may be any one of the first to third aspects), wherein the pressure reduction section comprises an exhaust fan unit, an exhaust pipe connecting the exhaust fan unit and the holding section, and a pressure reduction adjustment valve provided in the exhaust pipe, the opening degree of which is connected to the external space being adjusted by the suction adjustment section.

[0011] A fifth aspect of the present invention is the drawing device according to the fourth aspect, wherein the exhaust fan unit does not include an inverter circuit.

[0012] A sixth aspect of the present invention is the drawing apparatus of the first aspect (which may be any one of the first to fifth aspects), wherein the holding unit has a pressure gauge that acquires the pressure of the internal space connected to the plurality of suction holes, and the pressure of the internal space acquired by the pressure gauge is input to the suction adjustment unit, and the suction adjustment unit feedback controls the pressure reduction unit so that the pressure of the internal space becomes a target pressure corresponding to the type of substrate that the holding unit is to hold.

[0013] A seventh aspect of the present invention is a drawing apparatus according to the first aspect (which may be any one of the first to sixth aspects), in which the setting values ​​for the operation of the pressure reducing section include a first setting value which is applied from the start of suction of the substrate to the completion of suction, and a second setting value which is applied from the completion of suction of the substrate.

[0014] Aspect 8 of the present invention is a drawing device according to any one of aspects 1 to 7, further comprising a moving mechanism that moves at least one of the holding unit and the light irradiation unit in a direction parallel to the substrate held by the holding unit, thereby moving the holding unit relative to the light irradiation unit, and the light irradiation unit comprises a drawing head that emits modulated light toward the substrate held by the holding unit, and the moving mechanism moves the substrate held by the holding unit relative to the light irradiation unit while the drawing head is emitting modulated light, thereby drawing a pattern on the substrate. Effect of the Invention

[0015] According to the present invention, a plurality of types of substrates can be appropriately held in the drawing apparatus. [Brief description of the drawings]

[0016] [Figure 1] FIG. 1 is a perspective view showing a drawing apparatus. [Diagram 2] FIG. [Diagram 3] FIG. [Figure 4] FIG. [Diagram 5] FIG. [Figure 6] FIG. 4 is a diagram showing a configuration of a pressure reducing unit. [Figure 7] 4 is a block diagram showing the configuration of a suction adjustment unit and its surroundings. FIG. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0017] FIG. 1 is a perspective view showing a drawing apparatus 1 according to an embodiment of the present invention. The drawing apparatus 1 irradiates a photosensitive material forming the upper surface of a substrate 9 with spatially modulated light in a substantially beam-like form. Then, the light irradiation area is scanned over the substrate 9 to draw a pattern. The drawing apparatus 1 is a so-called direct drawing apparatus. In FIG. 1, three mutually orthogonal directions are indicated by arrows as the X direction, the Y direction, and the Z direction. The X direction and the Y direction are horizontal directions perpendicular to each other, and the Z direction is a vertical direction (i.e., an up-down direction). The same applies to other figures.

[0018] The substrate 9 is, for example, a substrate for manufacturing a printed wiring board having a substantially rectangular flat plate shape. On the (+Z) main surface (hereinafter also referred to as "upper surface 91") of the substrate 9, 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., an image of the circuit pattern is formed) on the resist film of the substrate 9. The type, shape, etc. of the substrate 9 may be changed in various ways.

[0019] The imaging device 1 includes a stage 21, a stage moving mechanism 22, an alignment unit 3, and a light irradiation unit 4. The stage 21 is a substantially rectangular flat member arranged below the alignment unit 3 and the light irradiation unit 4 (i.e., on the (-Z) side). The stage 21 includes a holder 25 that holds the horizontal substrate 9 from below. The holder 25 is a vacuum chuck that adsorbs and holds the lower surface of the substrate 9. The upper surface 91 of the substrate 9 placed on the holder 25 is substantially perpendicular to the Z direction and substantially parallel to the X and Y directions.

[0020] The drawing device 1 also includes a pressure reducing unit that generates a force for the holding unit 25 to suck in air, but this is not shown in FIG.

[0021] The stage moving mechanism 22 is a moving mechanism that moves the stage 21 relatively to the alignment unit 3 and the light irradiation unit 4 in a horizontal direction (i.e., a direction approximately parallel to the upper surface 91 of the substrate 9). The stage moving mechanism 22 is attached on the upper surface of the base 11 and is supported from below by the base 11. The stage moving mechanism 22 includes a first moving mechanism 23 and a second moving mechanism 24. The second moving mechanism 24 supports the stage 21 from below and linearly moves the stage 21 in the X direction along the guide rail. The first moving mechanism 23 supports the second moving mechanism 24 from below and linearly moves the stage 21 together with the second moving mechanism 24 in the Y direction along the guide rail. The driving sources of the first moving mechanism 23 and the second moving mechanism 24 are, for example, linear servo motors or motors attached to ball screws. The structures of the first moving mechanism 23 and the second moving mechanism 24 may be variously modified.

[0022] The drawing apparatus 1 may be provided with a stage rotation mechanism that rotates the stage 21 about a rotation axis extending in the Z direction. The drawing apparatus 1 may also be provided with a stage lifting mechanism that moves the stage 21 in the Z direction. For example, a servo motor can be used as the stage rotation mechanism. For example, a linear servo motor can be used as the stage lifting mechanism. The structures of the stage rotation mechanism and the stage lifting mechanism may be modified in various ways.

[0023] The alignment section 3 includes a plurality of alignment cameras 31. In the example shown in Fig. 1, 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 movement mechanism 22 by a support section 40 that is provided straddling the stage 21 and the stage movement mechanism 22. In the example shown in Fig. 1, the support section 40 is a gate-shaped member (a so-called gantry) that straddles the stage 21 and the stage movement mechanism 22, and is provided so as to stand up from the upper surface of the base 11.

[0024] 1, the two alignment cameras 31 are attached to the (+Y) side surface of the support unit 40. Of the two alignment cameras 31, for example, one alignment camera 31 is fixed to the support unit 40, and the other alignment camera 31 is movable in the X direction on the support unit 40. This makes it possible to change the distance in the X direction between the two alignment cameras 31. Note that the number of alignment cameras 31 in the alignment unit 3 may be one, or three or more.

[0025] Each alignment camera 31 captures an image of an alignment mark (not shown) provided in advance on the upper surface 91 of the substrate 9. In the drawing device 1, alignment of the substrate 9 (i.e., correction of the relative position of the substrate 9 with respect to the drawing head 41) is performed based on the image of the alignment mark acquired by the alignment camera 31.

[0026] The light irradiation unit 4 includes a plurality of drawing heads 41 (six in the example shown in FIG. 1) arranged in the X direction. The plurality of drawing heads 41 have approximately the same structure. Each drawing head 41 includes a spatial light modulator and emits modulated (i.e., spatially modulated) light downward. The spatial modulation may be two-dimensional modulation or one-dimensional modulation. Each drawing head 41 is supported above the stage 21 and the stage movement mechanism 22 by the above-mentioned support unit 40. In the example shown in FIG. 1, the six drawing heads 41 are attached to the support unit 40.

[0027] The six drawing heads 41 are arranged in a substantially straight line substantially parallel to the X direction. The six drawing heads 41 are positioned substantially the same in the Y and Z directions. Note that the multiple drawing heads 41 do not necessarily need to be arranged in a straight line, and may be arranged, for example, in a staggered manner. Furthermore, the light irradiation unit 4 may have one drawing head 41, or two or more drawing heads 41.

[0028] In the drawing device 1, pattern drawing on the substrate 9 is performed by a so-called multi-pass method. Specifically, while modulated light from the multiple drawing heads 41 of the light irradiation unit 4 is irradiated onto the upper surface 91 of the substrate 9, the first moving mechanism 23 of the stage moving mechanism 22 moves the substrate 9 in the Y direction to pass under the drawing heads 41. As a result, the irradiation area of ​​the light from the multiple drawing heads 41 is scanned in the Y direction on the substrate 9, and drawing on the substrate 9 is performed. In this way, the substrate 9 moves relatively to the light irradiation unit 4 while each drawing head 41 is emitting modulated light toward the substrate 9 held by the holding unit 25, and a pattern is drawn on the substrate 9.

[0029] Next, the second moving mechanism 24 moves the substrate 9 stepwise a predetermined distance in the X direction. Then, the first moving mechanism 23 moves the substrate 9 in the Y direction, and the drawing head 41 irradiates the substrate 9 with light again in parallel with the movement, thereby drawing on the substrate 9. In the drawing device 1, the irradiation of the substrate 9 moving in the Y direction with light and the step movement of the substrate 9 in the X direction are alternately performed, thereby drawing a pattern on the substrate 9.

[0030] In the following description, the Y direction is also referred to as the "main scanning direction" or simply the "scanning direction", and the X direction is also referred to as the "sub-scanning direction". The main scanning direction and the sub-scanning direction are directions that are approximately parallel to the upper surface 91 of the substrate 9. In the stage movement mechanism 22, the first movement mechanism 23 is a main scanning mechanism that moves the stage 21 relatively to the drawing head 41 in the main scanning direction. The second movement mechanism 24 is a sub-scanning mechanism that moves the stage 21 relatively to the drawing head 41 in the sub-scanning direction.

[0031] In the drawing apparatus 1, drawing on the substrate 9 may be performed by a single pass method (also called a one-pass method) in which drawing of a pattern on the substrate 9 is completed by moving the substrate 9 relatively to the drawing head 41 only once in the Y direction. In this case, sub-scanning of the substrate 9 by the second moving mechanism 24 (i.e., step movement in the X direction) is not performed when drawing the pattern. In other words, 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.

[0032] Next, the holding portion 25 will be described. Fig. 2 is a plan view of the holding portion 25. The upper surface of the holding portion 25 is a holding surface 251 that holds the substrate 9. A large number of suction holes 71 are provided in the holding surface 251. The suction holes 71 are arranged in the X direction and the Y direction so as to spread two-dimensionally on the holding surface 251. Each suction hole 71 is a minute hole.

[0033] FIG. 3 is a vertical cross-sectional view of the holding portion 25. In FIG. 3, the holding portion 25 is shown with emphasis on the thickness direction. The holding portion 25 has an upper plate 721, an intermediate member 722, and a lower member 723. The upper plate 721 is a plate-shaped member. The upper surface of the upper plate 721 is a flat holding surface 251. The plurality of suction holes 71 are through holes formed in the upper plate 721. The intermediate member 722 contacts the lower surface of the upper plate 721. The intermediate member 722 has a bottom portion 731 and a wall portion 732. The bottom portion 731 is plate-shaped. The wall portion 732 extends upward from the bottom portion 731. The bottom portion 731 is provided with a switching valve 733. The lower member 723 contacts the lower surface of the intermediate member 722. The lower member 723 has a bottom portion 734 and a wall portion 735. Wall portion 735 extends upwardly from bottom portion 734 .

[0034] FIG. 4 is a plan view of the intermediate member 722. The cross-sectional view of FIG. 3 shows a cross-section at the position of III-III in FIG. 4. The wall portion 732 includes an outer peripheral wall 741 provided on the outer periphery of the intermediate member 722, and two partition walls 742 and 743. The partition wall 742 is L-shaped and forms a small compartment 751 together with the outer peripheral wall 741. The partition wall 743 is also L-shaped and is located outside the compartment 751. The outer peripheral wall 741 and the partition walls 742 and 743 form a compartment 752 between the partition walls 742 and 743. The compartment 752 is an L-shaped compartment circumscribing the compartment 751. The outer peripheral wall 741 and the partition wall 743 form an L-shaped compartment 753 circumscribing the compartment 752.

[0035] At least one switching valve 733 is disposed in each of the sections 751, 752, and 753. For example, a solenoid valve is used as the switching valve 733. Each switching valve 733 switches between an open state and a closed state. When the switching valve 733 is closed, air cannot pass up and down through the bottom 731 at the position of the switching valve 733. When the switching valve 733 is open, air can pass up and down through the bottom 731 at the position of the switching valve 733. The upper ends of the outer peripheral wall 741 and the partition walls 742 and 743 contact the lower surface of the upper plate 721 (see FIG. 3), and the gap between the upper plate 721 and the wall section 732 is sealed so that air does not pass through. When the upper plate 721 contacts the intermediate member 722, the sections 751 to 753 become spaces that are enclosed in the vertical and horizontal directions.

[0036] 5 is a plan view of the lower member 723. The wall portion 735 is an outer peripheral wall provided on the outer periphery of the lower member 723. The upper end of the wall portion 735 contacts the lower surface of the bottom portion 731 of the intermediate member 722 (see FIG. 3), and the gap between the bottom portion 731 and the wall portion 735 is sealed so that air does not pass between them. When the bottom portion 731 contacts the lower member 723, a lower space 754 is formed that is surrounded in the vertical and horizontal directions by the bottom portion 731, the wall portion 735, and the bottom portion 734. An exhaust pipe 82 for exhausting air is connected to the bottom portion 734. A pressure gauge 756 for acquiring the pressure in the lower space 754 is provided in the lower space 754.

[0037] FIG. 6 is a diagram showing the configuration of the pressure reducing unit 8 connected to the holding unit 25. The pressure reducing unit 8 generates a force that causes the holding unit 25 to suck in air. The pressure reducing unit 8 has an exhaust fan unit 81, an exhaust pipe 82, an opening / closing valve 83, and a pressure reducing adjustment valve 84. The exhaust fan unit 81 is a device that exhausts air by rotating an impeller with a motor, and is, for example, a device called a blower. The exhaust fan unit 81 is a pressure reducing source. The exhaust pipe 82 connects the exhaust fan unit 81 and the holding unit 25 (see FIG. 3). The exhaust pipe 82 is flexible and deforms to follow the movement of the stage 21 including the holding unit 25.

[0038] The on-off valve 83 is a valve that switches between an open state and a closed state. For example, a solenoid valve is used as the on-off valve 83. The pressure reduction adjustment valve 84 is provided in the exhaust pipe 82. The pressure reduction adjustment valve 84 is an electric valve whose opening can be changed by an electric signal. The pressure reduction adjustment valve 84 adjusts the opening of the opening connecting the exhaust pipe 82 to the outside space. This adjusts the force with which the holding part 25 sucks the substrate 9. That is, when the opening of the pressure reduction adjustment valve 84 increases, outside air flows into the exhaust pipe 82, the reduced pressure state in the exhaust pipe 82 is relaxed, and the suction force in the holding part 25 decreases.

[0039] FIG. 7 is a block diagram showing the configuration of the suction adjustment unit 61, which adjusts the suction of air by the holding unit 25, and its peripherals. The suction adjustment unit 61 is realized by a computer (i.e., a general-purpose calculation device that operates by a program) or a dedicated calculation circuit. The suction adjustment unit 61 may be realized by combining a computer with a dedicated calculation circuit. The suction adjustment unit 61 is connected to a storage unit 62. The storage unit 62 is, for example, a semiconductor memory or a fixed disk. The storage unit 62 stores a plurality of types of the substrate 9. The "type" of the substrate 9 is information that can be used to specify the size of the substrate 9, the position and / or size of a through-hole if present, and the like, for example, a product number.

[0040] The overall control unit 60 shown in FIG. 7 controls the overall operation of the imaging device 1. The overall control unit 60 is realized by a computer (i.e., a general-purpose arithmetic device that operates according to a program) or a dedicated arithmetic circuit. The overall control unit 60 may be realized by combining a computer with a dedicated arithmetic circuit. The functions of the suction adjustment unit 61 and the memory unit 62 may be included in the overall control unit 60. Although the illustration is simplified in FIG. 7, the overall control unit 60 also controls the operation timing of the suction adjustment unit 61 and the operations of the stage movement mechanism 22, the alignment unit 3, the light irradiation unit 4, etc.

[0041] Next, the operation of the holder 25 to hold the substrate 9 will be described. Before the holder 25 holds the substrate 9, the exhaust fan unit 81 is driven with the on-off valve 83 closed. The type of the substrate 9 to be held by the holder 25 is input from the storage unit 62 to the suction adjustment unit 61. More precisely, information indicating the type of the substrate 9 is input to the suction adjustment unit 61. The suction adjustment unit 61 controls the opening and closing of each switching valve 733 based on the type of the substrate 9, and adjusts the opening degree of the pressure reduction adjustment valve 84.

[0042] 2 to 5 can hold a substrate 9 having the size of the section 751 in FIG. 4 (hereinafter referred to as a "small size substrate 9"), a substrate 9 having the size of the sections 751 and 752 combined (hereinafter referred to as a "medium size substrate 9"), and a substrate 9 having the size of the sections 751 to 753 combined (hereinafter referred to as a "large size substrate 9"). When the holder 25 holds the small size substrate 9, the suction adjuster 61 opens only the switching valve 733 in the section 751, and closes the other switching valves 733. The suction adjuster 61 also controls the pressure reducing adjuster valve 84 so that the opening degree corresponds to the type of the substrate 9 being held.

[0043] In parallel with the above operation, or before or after the above operation, the small-sized substrate 9 is placed in an area of ​​the holding surface 251 corresponding to the section 751 in Fig. 2. Then, under the control of the overall control unit 60, the on-off valve 83 is opened, reducing the pressure in the exhaust pipe 82, the lower space 754, and the section 751, and suction is performed through the suction hole 71 above the section 751. As a result, the small-sized substrate 9 is sucked and held on the holding surface 251. Because the switching valves 733 of the sections 752 and 753 are closed, suction is not performed through the suction holes 71 that do not overlap with the small-sized substrate 9.

[0044] When the holding unit 25 holds the medium-sized substrate 9, the operation is similar to that of holding the small-sized substrate 9, except that the switching valves 733 of the sections 751 and 752 are opened and the other switching valves 733 are closed. When the holding unit 25 holds the large-sized substrate 9, the operation is similar to that of holding the small-sized substrate 9, except that the switching valves 733 of all the sections 751 to 753 are opened. In this way, the holding unit 25 can hold the substrate 9 by selectively sucking air only from the multiple suction holes 71 that overlap the substrate 9 in accordance with the size of the substrate 9.

[0045] As described above, when the holder 25 holds the substrate 9, the type of the substrate 9 to be held by the holder 25 is (automatically) read from the memory 62 and input to the suction adjustment unit 61, and the opening degree of the pressure reduction adjustment valve 84, which is the set value for the operation of the pressure reduction unit 8, is (automatically) changed according to the type of the substrate 9, thereby adjusting the force with which the holder 25 sucks the substrate 9. Here, "automatically" means that it is not performed through a direct operation of the operator. This allows the suction conditions of the substrate 9 to be made appropriate, and appropriate holding according to the type of the substrate 9 is realized. That is, the drawing device 1 can appropriately hold substrates of a plurality of types. Here, the above "suction conditions" means the change in the contact state between the substrate 9 and the holder 25 from the start of suction to the completion of suction, and / or the contact state between the substrate 9 and the holder 25 after the completion of suction.

[0046] Furthermore, in the drawing device 1, by adjusting the setting value of the pressure reducing unit 8 for each type of substrate 9, it is possible to suppress the suction force per unit area for the substrate 9 from varying depending on the size of the substrate 9 and the presence of through holes in the substrate 9. This makes it possible to make the effect of suction on the substrate 9, that is, the suction conditions of the substrate 9 in the vicinity of the suction holes 71, the same or similar even if the type of substrate 9 is different. In particular, when the substrate 9 has resist layers on both the top and bottom surfaces, it is possible to suppress the state of the suction marks generated in the portions of the resist layers that contact the periphery of the suction holes 71 from varying depending on the type of substrate 9.

[0047] To be precise, the force with which the holder 25 sucks the substrate 9 changes over time from when suction begins to when adsorption is completed. That is, in the exhaust fan unit, the suction force changes according to the flow rate. In the above explanation, "adjusting the force with which the substrate 9 is sucked" means to increase or decrease overall the suction force that changes according to the flow rate, i.e., the decompression force. In other words, "adjusting the suction force" means to increase or decrease the suction force at any flow rate (including when the flow rate is zero).

[0048] In the drawing apparatus 1, when the holding of the substrate 9 is completed, the holding force of the substrate 9, that is, the force with which the holding unit 25 sucks the substrate 9, may be feedback-controlled. Specifically, a plurality of target pressures corresponding to the type of the substrate 9 are prepared in advance in the storage unit 62 shown in FIG. 7, and the target pressure corresponding to the type of the substrate 9 to be held is input to the suction adjustment unit 61. Then, when the on-off valve 83 is opened in the above operation and the suction is completed, the pressure of the lower space 754 acquired by the pressure gauge 756 (i.e., the pressure of the internal space of the holding unit 25) is repeatedly input to the suction adjustment unit 61, and the suction adjustment unit 61 feedback-controls the pressure reduction unit 8 so that the pressure of the lower space 754 becomes the target pressure corresponding to the type of the substrate 9 held by the holding unit 25. In the case of the configuration of FIG. 6, the opening degree of the pressure reduction adjustment valve 84 is controlled by the suction adjustment unit 61, and the suction force by the holding unit 25 is feedback-controlled. The "suction force" by the holding portion 25 is, to be precise, the suction force by the holding portion 25 per unit area of ​​the substrate 9, and the same applies to the following description of the suction force of the holding portion 25.

[0049] The pressure of the lower space 754 acquired by the pressure gauge 756 is the pressure of the internal space of the holding part 25 connected to the multiple suction holes 71. The internal space here means the decompressed space within the space inside the holding part 25 that is used for suction.

[0050] By performing feedback control according to the type of substrate 9, it is possible to appropriately hold substrate 9 even if the type of substrate 9 differs. It is also possible to prevent the suction force per unit area from differing depending on the type of substrate 9.

[0051] In the above operation example in which feedback control is performed after the substrate 9 is suctioned, the set values ​​for the operation of the pressure reducing unit 8 include the opening degree (first set value) of the pressure reducing adjustment valve 84 from the start of suction of the substrate 9 to the completion of suction, and the target pressure (second set value) of the lower space 754 that is applied to the feedback control from the completion of suction of the substrate 9. However, various set values ​​may be adopted as the first set value for the operation of the pressure reducing unit 8 from the start of suction of the substrate 9 to the completion of suction (hereinafter referred to as the "first pressure reducing operation") and the second set value for the operation of the pressure reducing unit 8 that is applied from the completion of suction of the substrate 9 (hereinafter referred to as the "second pressure reducing operation"). Note that the time when "suction is completed" refers to the time when the suction force with which the holder 25 holds the substrate 9 becomes a preset magnitude.

[0052] As the first decompression operation, the suction adjustment unit 61 may feedback-control the decompression unit 8 so that the pressure in the internal space of the holding unit 25 becomes a target pressure corresponding to the type of the substrate 9. Specifically, an ideal target pressure of the lower space 754 from the start of suction of the substrate 9 to the completion of suction (a target pressure at the completion of suction, or a target pressure that changes with time from the start of suction) may be input from the storage unit 62 to the suction adjustment unit 61 as a first set value, and the decompression adjustment valve 84 may be feedback-controlled based on the pressure acquired by the pressure gauge 756 so that the pressure changes according to this target pressure. This adjusts the change over time in the contact state between the holding surface 251 and the substrate 9 at the moment when the holding unit 25 adsorbs the substrate 9, thereby realizing appropriate holding of the substrate 9.

[0053] On the other hand, feedback control may not be performed as the second decompression operation. Specifically, an ideal aperture of the decompression adjusting valve 84 for each type of substrate 9 may be acquired in advance and stored in the storage unit 62 as a second set value, and an aperture according to the type of substrate 9 may be input to the suction adjusting unit 61, and the aperture of the decompression adjusting valve 84 may be (automatically) fixed to the predetermined aperture after suction of the substrate 9 is completed. This allows the substrate 9 to be held appropriately.

[0054] As described above, various operations may be performed as the first depressurization operation and the second depressurization operation, and by setting the first set value and the second set value for each type of substrate 9, appropriate holding according to the type of substrate 9 is realized. Usually, when an operation using the first set value and the second set value is performed, the opening degree of the depressurization adjustment valve 84 having the first set value (or found based on the first set value) is smaller than the opening degree of the depressurization adjustment valve 84 having the second set value (or found based on the second set value) set for the same substrate 9. That is, an operation is performed to reduce the suction force at the moment when the suction of the substrate 9 is completed.

[0055] Furthermore, the first set value may be determined for each type of substrate 9 so that the change in suction force from the start of suction of substrate 9 to the completion of suction is similar even if the type of substrate 9 is different, and the second set value may be determined for each type of substrate 9 so that the suction force from the completion of suction of substrate 9 is similar even if the type of substrate 9 is different. This makes it possible to make the effect of suction on substrate 9, that is, the suction conditions of substrate 9 in the vicinity of suction holes 71, the same or similar even if the type of substrate 9 is different.

[0056] For example, when multiple suction marks are generated on the substrate 9 by suction, the multiple suction marks can be approximated regardless of the type of the substrate 9. In particular, when the substrate 9 has resist layers on both the top and bottom surfaces, it is possible to prevent the state of the suction marks generated in the portion of the resist layer that contacts the periphery of the suction hole 71 from changing depending on the type of the substrate 9.

[0057] Since the number of suction holes 71 used for suction and holding varies depending on the size of the substrate 9, when a large substrate 9 is suctioned, the flow rate of air drawn into the holder 25 from one suction hole 71 immediately after the start of suction (the amount of air drawn in a given short time) is smaller than when a small substrate is suctioned. As a result, when the aperture of the pressure reducing adjustment valve 84 is constant, the change in the suction conditions that occurs depending on the size of the substrate 9 becomes large. Therefore, it is particularly preferable that the operation of the pressure reducing unit 8 is changed for each type of substrate 9 when applied to a drawing apparatus 1 that can hold substrates 9 of different sizes. In general, the larger the size of the substrate 9, the smaller the aperture of the aperture of the pressure reducing adjustment valve 84.

[0058] Since the pressure reducing unit 8 is preferably applied to a drawing device that draws on substrates 9 of different sizes, it is preferable that the pressure reducing unit 8 is applied to a direct drawing device having such a function. That is, the pressure reducing unit 8 is suitable for a device that draws a pattern on the substrate 9 by moving the substrate 9 relatively to the light irradiating unit 4 while the light irradiating unit 4 (or the drawing head 41) emits modulated light toward the substrate 9 held by the holding unit 25.

[0059] In the drawing device 1, a pressure reduction adjustment valve 84 is provided on an exhaust pipe 82 connected to an exhaust fan unit 81, and the opening of the pressure reduction adjustment valve 84 that is connected to the external space is adjusted by the suction adjustment section 61. That is, when adjusting the suction force in the holding section 25, the exhaust force of the exhaust fan unit 81 is not adjusted. This allows the pressure reduction section 8 to be realized with a simple configuration. Since there is no need to control the exhaust force of the exhaust fan unit 81, which is a negative pressure source, that is, the output of the internal motor, a low-cost exhaust fan unit without an inverter circuit can be used as the exhaust fan unit 81. This allows the pressure reduction section 8 to be configured at low cost.

[0060] The rendering device 1 may be modified in various ways.

[0061] For example, the internal structure of the holding unit 25 that holds the substrate 9 by sucking air through the multiple suction holes 71 may be modified in various ways. The holding unit 25 may be a dedicated holding unit for holding substrates 9 of one size. In this case, the intermediate member 722 can be omitted. The holding surface 251 does not have to be entirely flat.

[0062] In the imaging apparatus 1, the position of the holding unit 25 may be fixed, and the light irradiation unit 4 may move relative to the holding unit 25 to perform imaging on the substrate 9. That is, the imaging apparatus 1 is provided with a moving mechanism that moves at least one of the holding unit 25 and the light irradiation unit 4 in a direction parallel to the substrate 9 held by the holding unit 25 (i.e., a direction parallel to the upper surface 91) to move the holding unit 25 relatively to the light irradiation unit 4. Of course, both the holding unit 25 and the light irradiation unit 4 may move in a direction parallel to the substrate 9. Note that the imaging apparatus 1 may be an apparatus in which the stage moving mechanism 22 does not exist.

[0063] The drawing device 1 is not limited to a so-called direct drawing device. The pressure reducing unit 8 used for suction holding of the substrate 9 by the holding unit 25 can be used in various devices that draw a pattern on the substrate 9 by irradiating light. For example, the pressure reducing unit 8 can be used in a device that irradiates a mask on which a pattern is formed with light and irradiates the substrate with the light that has passed through the mask, thereby drawing a pattern on the substrate 9. In this way, various configurations that draw a pattern on the substrate 9 by emitting light toward the substrate 9 held by the holding unit 25 can be adopted as the light irradiating unit 4 in the drawing device 1.

[0064] The substrate 9 is not limited to a substrate for a printed wiring board, but may be a glass substrate for a mask substrate or a substrate for other purposes.

[0065] 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]

[0066] 1 Drawing device 4. Light irradiation unit 8 Pressure reduction section 9 Substrate 22 Stage movement mechanism 25 Holding part 41 Drawing head 61 Suction adjustment section 62 Storage section 71 Suction hole 81 Exhaust fan unit 82 Exhaust pipe 84 Pressure reducing valve 756 Pressure Gauge

Claims

1. A drawing apparatus for drawing a pattern on a substrate by irradiating the substrate with light, comprising: a holder that holds the substrate by sucking air through a plurality of suction holes; a pressure reducing section connected to the holding section and generating a force for the holding section to suck air; A storage unit that stores a plurality of types of substrates; a suction adjustment unit that reads out and inputs the type of the substrate to be held by the holder from the storage unit, and adjusts the force with which the holder sucks the substrate by changing a setting value for the operation of the pressure reduction unit in accordance with the type of the substrate; a light irradiation unit that emits light toward the substrate held by the holder to draw a pattern on the substrate; A drawing device comprising:

2. The drawing device according to claim 1 , The holding unit is capable of holding the substrate by selectively sucking air from the plurality of suction holes in accordance with a size of the substrate.

3. The drawing device according to claim 1 , A drawing apparatus in which the substrate held by the holding part has resist layers on both sides.

4. The drawing device according to claim 1 , The pressure reducing section is Exhaust fan unit; an exhaust pipe connecting the exhaust fan unit and the holding portion; a pressure reducing adjustment valve provided in the exhaust pipe, the pressure reducing adjustment valve adjusting the opening degree of an opening communicating with an external space by the suction adjustment unit; A drawing device comprising:

5. The drawing device according to claim 4, The drawing apparatus, wherein the exhaust fan unit does not have an inverter circuit.

6. The drawing device according to claim 1 , the holding unit has a pressure gauge for acquiring a pressure in an internal space connected to the plurality of suction holes, The pressure of the internal space acquired by the pressure gauge is input to the suction adjustment unit, The suction adjustment unit feedback-controls the pressure reduction unit so that the pressure in the internal space becomes a target pressure corresponding to the type of substrate that the holding unit is to hold.

7. The drawing device according to claim 1 , A drawing apparatus in which the setting values ​​for the operation of the pressure reducing unit include a first setting value that is applied from the start of suction of the substrate to the completion of suction, and a second setting value that is applied from the completion of suction of the substrate.

8. 8. The drawing device according to claim 1, a moving mechanism for moving at least one of the holding unit and the light irradiation unit in a direction parallel to the substrate held by the holding unit, thereby moving the holding unit relative to the light irradiation unit; the light irradiation unit includes a drawing head that emits modulated light toward the substrate held by the holding unit, A drawing device in which a pattern is drawn on a substrate by the moving mechanism moving the substrate held in the holding unit relative to the light irradiation unit while the drawing head is emitting modulated light.

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