Drawing apparatus

Abstract

The present invention provides a drawing apparatus that draws a pattern on a substrate by irradiation of light, the drawing apparatus comprising: a holding unit (25) that holds the substrate by suctioning air from a plurality of suction holes; a pressure reduction unit (8) that generates a force that the holding unit (25) sucks air; a storage unit (62) that stores a plurality of models of the substrate; and a suction adjustment unit (61) that adjusts the force of the holding unit (25) that absorbs the substrate by changing the setting value of the operation of the pressure reduction unit (8) in accordance with the type of the substrate.

Description

[0001] [Reference to related applications]

[0002] This application claims the benefit of priority of Japanese patent application JP2023-154058 filed on September 21, 2023, and incorporates the entire disclosure of that application into this application. Technical Field

[0003] The present invention relates to a drawing device for drawing a pattern on a substrate by irradiating light. Background Art

[0004] Conventionally, when drawing a pattern on a printed circuit board, a semiconductor substrate, etc. (hereinafter referred to as a "substrate"), a drawing device is used that irradiates light to a photosensitive material formed on the substrate to draw a pattern on the photosensitive material. In such a drawing device, the substrate is sometimes held by sucking air from a suction hole provided in a holding portion.

[0005] For example, in the exposure device (drawing device) disclosed in Japanese Patent Gazette No. 2011-191755 (Document 1), a workpiece chuck holding a substrate holds the substrate by vacuum adsorption. The workpiece chuck has: a central adsorption area, an annular adsorption area surrounding the outer side of the central adsorption area, and three adsorption areas located outside the annular adsorption area. Each adsorption area is divided by a partition wall and a peripheral wall. In addition, there are a plurality of protrusions with the same height as the partition wall in each adsorption area. Moreover, in order to suppress the deflection of the substrate, the air conditioner connected to each adsorption area is adjusted according to the area of ​​each adsorption area, thereby making the pressure in each adsorption area become approximately constant.

[0006] However, in the case where a plurality of substrates of different models can be held in the drawing device, the size of the substrates and the positions of the holes of the substrates are different due to the different models. Therefore, when the substrates are simply adsorbed by suction, the adsorption force will differ depending on the model of the substrate, and the change in the contact state between the substrate and the holding part from the start of adsorption to the completion of adsorption or the contact state after adsorption will differ depending on the model. As a result, when holding a substrate of a specific model, the suction may have an undesirable effect on the substrate. Summary of the invention

[0007] An object of the present invention is to appropriately hold substrates of a plurality of types in a drawing device.

[0008] Mode 1 of the present invention is a drawing device that draws a pattern on a substrate by irradiation with light, wherein the device comprises: a holding portion that holds the substrate by sucking air from a plurality of suction holes; a decompression portion that is connected to the holding portion and generates a force for the holding portion to suck air; a storage portion that stores a plurality of models of substrates; a suction adjustment portion that reads out the model of a predetermined substrate held by the holding portion from the storage portion and inputs the model into the suction adjustment portion, and changes the set value of the action of the decompression portion according to the model of the substrate, thereby adjusting the force of the holding portion to suck the substrate; and a light irradiation portion that draws a pattern on the substrate by emitting light to the substrate held by the holding portion.

[0009] According to the first aspect of the present invention, in the drawing device, it is possible to appropriately hold substrates of a plurality of types.

[0010] According to a second aspect of the present invention, in the drawing device according to the first aspect, the holding section can hold the substrate by selectively sucking air from the plurality of suction holes according to the size of the substrate.

[0011] A third aspect of the present invention is, in the drawing device of the first aspect (may be the first or second aspect), wherein the substrate held by the holding portion has resist layers on both surfaces.

[0012] According to mode 4 of the present invention, in the drawing device of mode 1 (or any one of modes 1 to 3), the decompression portion comprises: an exhaust fan unit; an exhaust pipe connecting the exhaust fan unit and the retaining portion; and a decompression adjustment valve arranged on the exhaust pipe, which adjusts the opening of the opening connected to the external space by using the suction adjustment portion.

[0013] According to a fifth aspect of the present invention, in the drawing device of the fourth aspect, the exhaust fan unit does not have an inverter circuit.

[0014] According to mode 6 of the present invention, in the drawing device of mode 1 (or any one of modes 1 to 5), the holding portion has a pressure gauge, which obtains the internal space pressure connected to the plurality of suction holes, and the internal space pressure obtained by the pressure gauge is input to the suction adjustment portion, and the suction adjustment portion performs feedback control on the decompression portion so that the internal space pressure becomes a target pressure corresponding to the model of the predetermined substrate held by the holding portion.

[0015] According to mode 7 of the present invention, in the drawing device of mode 1 (or any one of modes 1 to 6), as the setting value for the action of the decompression portion, there exists a first setting value from the moment when the attraction of the substrate is started to the moment when the attraction is completed, and a second setting value applied from the moment when the attraction of the substrate is completed.

[0016] According to mode 8 of the present invention, in the drawing device of any one of modes 1 to 7, the drawing device further comprises a moving mechanism, wherein the moving mechanism moves the holding portion relative to the light irradiation portion by moving at least one of the holding portion and the light irradiation portion in a direction parallel to the substrate held by the holding portion, the light irradiation portion comprises a drawing head, and the drawing head emits modulated light toward the substrate held by the holding portion, and while the drawing head emits the modulated light, the moving mechanism moves the substrate held by the holding portion relative to the light irradiation portion, thereby drawing a pattern on the substrate.

[0017] The above-mentioned objects 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

[0018] Figure 1 It is a perspective view showing a drawing device.

[0019] Figure 2 It is a top view of the holding portion.

[0020] Figure 3 It is a longitudinal sectional view of the retaining portion.

[0021] Figure 4 It is a top view of the intermediate component.

[0022] Figure 5 It is a top view of the lower component.

[0023] Figure 6 It is a diagram showing the structure of a pressure reducing unit.

[0024] Figure 7 This is a block diagram showing the structure of the suction adjustment unit and its periphery.

[0025] Description of reference numerals:

[0026] 1 Drawing device

[0027] 4 Light irradiation part

[0028] 8 Decompression section

[0029] 9 substrate

[0030] 22 Stage moving mechanism

[0031] 25. Maintaining part

[0032] 41 Drawing Head

[0033] 61 Attraction Adjustment Department

[0034] 62 Storage

[0035] 71 suction hole

[0036] 81 Exhaust fan unit

[0037] 82 Exhaust pipe

[0038] 84 Pressure reducing regulating valve

[0039] 756 Pressure gauge DETAILED DESCRIPTION

[0040] Figure 1 1 is a perspective view showing a drawing device 1 according to an embodiment of the present invention. The drawing device 1 irradiates a photosensitive material forming the upper surface of a substrate 9 with a substantially light beam after spatial modulation. Then, the pattern is drawn by scanning the irradiation area of ​​the light on the substrate 9. The drawing device 1 is a so-called direct drawing device. Figure 1 In the figure, arrows are used to indicate three mutually orthogonal directions 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-and-down direction). The same is true in other figures.

[0041] The substrate 9 is, for example, a substrate for manufacturing a printed wiring 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 on the resist film of the substrate 9 (that is, an image of the circuit pattern is formed). In addition, the type and shape of the substrate 9 can be changed in various ways.

[0042] The drawing 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 plate-shaped member disposed on the lower side (i.e., the (-Z) side) than the alignment unit 3 and the light irradiation unit 4. The stage 21 includes a holding unit 25 for holding a substrate 9 in a horizontal state from the lower side. The holding unit 25 is a vacuum chuck for holding the lower surface of the substrate 9 by adsorbing it. The upper surface 91 of the substrate 9 placed on the holding unit 25 is substantially perpendicular to the Z direction and substantially parallel to the X direction and the Y direction.

[0043] The drawing device 1 also has a decompression unit that generates a force for the holding unit 25 to suck air, but Figure 1 Illustration omitted.

[0044] The stage moving mechanism 22 is a moving mechanism that moves the stage 21 relative to the alignment section 3 and the light irradiation 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 source of the first moving mechanism 23 and the second moving mechanism 24 is, for example, a linear servo motor or a driving source 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.

[0045] The drawing device 1 may be provided with a stage rotating mechanism that rotates the stage 21 around a rotation axis extending in the Z direction. In addition, the drawing device 1 may be provided with a stage lifting mechanism that moves the stage 21 in the Z direction. 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.

[0046] 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 40 provided across the stage 21 and the stage moving mechanism 22. Figure 1 In the illustrated example, the support portion 40 is a door-shaped member (so-called gantry) that spans the stage 21 and the stage moving mechanism 22 , and is provided so as to stand upright from the upper surface of the base 11 .

[0047] 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 40. For example, one of the two alignment cameras 31 is fixed to the support portion 40, and the other alignment camera 31 is movable in the X direction on the support portion 40. 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.

[0048] 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.

[0049] The light irradiation unit 4 has a plurality of light irradiation units arranged in the X direction (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 spatial light modulator that emits modulated (i.e., spatially modulated) light downward. Spatial modulation can be two-dimensional modulation or one-dimensional modulation. Each drawing head 41 is supported by the support portion 40 above the stage 21 and the stage moving mechanism 22. Figure 1 In the illustrated example, six drawing heads 41 are attached to the support portion 40 .

[0050] The 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. In addition, the plurality of drawing heads 41 are not necessarily arranged in a straight line, and may be arranged in a staggered manner, for example. In addition, in the light irradiation unit 4, the number of the drawing heads 41 may be one or more than two.

[0051] In the drawing device 1, the pattern drawing on the substrate 9 is performed in a so-called multi-path method. Specifically, modulated light is irradiated from the plurality of drawing heads 41 of the light irradiation unit 4 onto the upper surface 91 of the substrate 9, and the substrate 9 is moved in the Y direction by the first moving mechanism 23 of the stage moving mechanism 22 to pass under the drawing heads 41. Thus, the irradiation area of ​​the light from the plurality of drawing heads 41 is scanned in the Y direction on the substrate 9, and the drawing of the substrate 9 is performed. In this way, while each drawing head 41 emits modulated light to the substrate 9 held by the holding unit 25, the substrate 9 moves relative to the light irradiation unit 4, so that a pattern is drawn on the substrate 9.

[0052] Next, the substrate 9 is moved in steps by a predetermined distance in the X direction by the second moving mechanism 24. 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, thereby drawing on the substrate 9. In the drawing device 1, a pattern is drawn on the substrate 9 by alternately irradiating the substrate 9 moving in the Y direction with light and stepping the substrate 9 in the X direction.

[0053] In the following description, the Y direction is referred to as the "main scanning direction" or simply the "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.

[0054] In the drawing device 1, the substrate 9 may be drawn using a single path method (also referred to as a single stroke 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.

[0055] Next, the holding portion 25 will be described. Figure 2 2 is a top view of the holding portion 25. The upper surface of the holding portion 25 is a holding surface 251 for holding the substrate 9. A plurality of suction holes 71 are provided on the holding surface 251. The suction holes 71 are arranged in the X direction and the Y direction so as to expand two-dimensionally on the holding surface 251. Each suction hole 71 is a tiny hole.

[0056] Figure 3 25 is a longitudinal sectional view of the retaining portion 25. Figure 3 , the holding portion 25 is highlighted in 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 is in contact with the lower surface of the upper plate 721. The intermediate member 722 has a bottom 731 and a wall 732. The bottom 731 is plate-shaped. The wall 732 extends upward from the bottom 731. A switching valve 733 is provided at the bottom 731. The lower member 723 is in contact with the lower surface of the intermediate member 722. The lower member 723 has a bottom 734 and a wall 735. The wall 735 extends upward from the bottom 734.

[0057] Figure 4 722 is a top view of the intermediate member 722. Figure 3 The cross-sectional view shows Figure 4The cross section at the position III-III in the figure. The wall portion 732 includes an outer peripheral wall 741 and two partition walls 742 and 743 provided on the outer periphery of the intermediate member 722. The partition wall 742 is L-shaped and forms a small partition 751 together with the outer peripheral wall 741. The partition wall 743 is also L-shaped and is located outside the partition 751. The partition 752 is formed between the partition walls 742 and 743 by the outer peripheral wall 741 and the partition walls 742 and 743. The partition 752 is an L-shaped partition circumscribing the partition 751. The L-shaped partition 753 circumscribing the partition 752 is formed by the outer peripheral wall 741 and the partition walls 743.

[0058] At least one switching valve 733 is arranged in each of the partitions 751, 752, and 753. As the switching valve 733, for example, a solenoid valve is used. Each switching valve 733 switches between an open state and a closed state. When the switching valve 733 is in a closed state, air cannot pass through the bottom 731 in the upward and downward direction at the position of the switching valve 733. When the switching valve 733 is in an open state, air can pass through the bottom 731 in the upward and downward direction at the position of the switching valve 733. The upper ends of the peripheral wall 741 and the partition walls 742 and 743 are in contact with the lower surface of the upper plate 721 (refer to Figure 3 ), the space between the upper plate 721 and the wall portion 732 is sealed in a manner that air cannot pass through. The upper plate 721 is in contact with the intermediate member 722, so that the partitions 751 to 753 become spaces surrounded in the vertical direction and the horizontal direction.

[0059] Figure 5 735 is a peripheral wall provided on the outer periphery of the lower member 723. The upper end of the wall 735 is in contact with the lower surface of the bottom 731 of the intermediate member 722 (see Figure 3 ), the bottom 731 and the wall 735 are sealed in a way that air cannot pass through. The bottom 731 and the lower member 723 are in contact, and a lower space 754 surrounded in the vertical direction and the horizontal direction is formed by the bottom 731, the wall 735 and the bottom 734. The exhaust pipe 82 for exhausting air is connected to the bottom 734. A pressure gauge 756 for obtaining the pressure in the lower space 754 is provided in the lower space 754.

[0060] Figure 6 1 is a diagram showing the structure of the pressure reducing unit 8 connected to the holding unit 25. The pressure reducing unit 8 generates a force for the holding unit 25 to suck air. The pressure reducing unit 8 includes an exhaust fan unit 81, an exhaust pipe 82, an on-off valve 83, and a pressure reducing regulating valve 84. The exhaust fan unit 81 is a device that exhausts air by rotating an impeller using a motor, such as 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. 1 ). Figure 3The exhaust pipe 82 has flexibility and deforms in accordance with the movement of the stage 21 including the holding portion 25 .

[0061] The opening and closing valve 83 is a valve that switches between an open state and a closed state. As the opening and closing valve 83, for example, a solenoid valve is used. The decompression regulating valve 84 is provided in the exhaust pipe 82. The decompression regulating valve 84 is an electric valve that can change the opening according to an electrical signal. The opening of the opening connecting the exhaust pipe 82 and the external space is adjusted by the decompression regulating valve 84. Thus, the force of the holding part 25 to attract the substrate 9 is adjusted. That is, when the opening of the decompression regulating valve 84 becomes larger, the external air flows into the exhaust pipe 82, the decompression state in the exhaust pipe 82 is relieved, and the attraction force in the holding part 25 is reduced.

[0062] Figure 7 It is a block diagram showing the structure of the suction adjustment unit 61 and its surroundings for adjusting the suction of air performed by the holding unit 25. The suction adjustment unit 61 is implemented by a computer (i.e., a general-purpose computing device that operates through a program) or a dedicated computing circuit. The suction adjustment unit 61 can also be implemented by combining a computer and a dedicated computing circuit. The suction adjustment unit 61 is connected to the storage unit 62. The storage unit 62 is, for example, a semiconductor memory or a fixed disk. The storage unit 62 stores multiple models of the substrate 9. The "model" of the substrate 9 refers to information used to determine the size of the substrate 9, the position and / or size of the through hole when there is a through hole, etc., such as a product number.

[0063] Figure 7 The overall control unit 60 shown controls the overall operation of the drawing device 1. The overall control unit 60 is implemented by a computer (i.e., a general-purpose computing device that operates according to a program) or a dedicated computing circuit. The overall control unit 60 can also be implemented by combining a computer and a dedicated computing circuit. The functions of the suction adjustment unit 61 and the storage unit 62 can also be included in the overall control unit 60. Figure 7 Although the illustration is simplified, the overall control unit 60 also controls the operation timing of the suction adjustment unit 61, the operation of the stage moving mechanism 22, the alignment unit 3, the light irradiation unit 4, etc.

[0064] Next, the operation of the holding portion 25 holding the substrate 9 will be described. In the stage before the holding portion 25 holds the substrate 9, the exhaust fan unit 81 is driven in a state where the opening and closing valve 83 is closed. The model of the predetermined substrate 9 held by the holding portion 25 is input from the storage portion 62 to the suction adjustment portion 61. More precisely, information indicating the model of the substrate 9 is input to the suction adjustment portion 61. The suction adjustment portion 61 controls the opening and closing of each switching valve 733 based on the model of the substrate 9, and adjusts the opening degree of the pressure reduction adjustment valve 84.

[0065] Specifically, in Figures 2 to 5 In the holding portion 25 shown, it is possible to hold Figure 4Substrates 9 of the size of partition 751 (hereinafter referred to as "small-sized substrates 9"), substrates 9 of the size of partition 751 and partition 752 combined (hereinafter referred to as "medium-sized substrates 9"), and substrates 9 of the size of partitions 751 to 753 combined (hereinafter referred to as "large-sized substrates 9"). When the holding portion 25 holds a small-sized substrate 9, the suction adjustment portion 61 is used to open only the switching valve 733 in the partition 751, and the other switching valves 733 are closed. In addition, the suction adjustment portion 61 controls the decompression adjustment valve 84 to make it open to a degree corresponding to the model of the substrate 9 being held.

[0066] In parallel with the above-mentioned action or before or after the above-mentioned action, the small-sized substrate 9 is placed on the Figure 2 Then, the opening and closing valve 83 is opened by the control of the overall control unit 60, so that the exhaust pipe 82, the lower space 754 and the partition 751 are decompressed, and suction is performed from the suction hole 71 on the partition 751. As a result, the small-sized substrate 9 is adsorbed and held on the holding surface 251. Since the switching valves 733 of the partitions 752 and 753 are in the closed state, suction is not performed from the suction hole 71 overlapping with the small-sized substrate 9.

[0067] When the holding portion 25 holds a medium-sized substrate 9, in the above-mentioned operation for holding a small-sized substrate 9, except that the switching valves 733 of the partitions 751 and 752 are in an open state and the other switching valves 733 are in a closed state, the operation is performed based on the operation for holding the small-sized substrate 9. When the holding portion 25 holds a large-sized substrate 9, in the above-mentioned operation for holding a small-sized substrate 9, except that the switching valves 733 of all the partitions 751 to 753 are in an open state, the operation is performed based on the operation for holding the small-sized substrate 9. In this way, in the holding portion 25, the substrate 9 can be held by selectively sucking air only from the plurality of suction holes 71 overlapping the substrate 9 in accordance with the size of the substrate 9.

[0068] As described above, when the holding portion 25 holds the substrate 9, the model of the predetermined substrate 9 held by the holding portion 25 is read out from the storage portion 62 (automatically) and input into the suction adjustment portion 61, and the opening of the pressure reducing adjustment valve 84, which is the set value of the action of the pressure reducing portion 8, is changed (automatically) according to the model of the substrate 9, thereby adjusting the force of the holding portion 25 to attract the substrate 9. In addition, "automatically" means not directly operated by the operator. In this way, the adsorption conditions of the substrate 9 can be made appropriate conditions, so that appropriate holding corresponding to the model of the substrate 9 can be achieved. That is, in the drawing device 1, multiple models of substrates can be appropriately held. In addition, the above-mentioned "adsorption conditions" refer to the change in the contact state between the substrate 9 and the holding portion 25 from the start of adsorption to the completion of adsorption and / or the contact state between the substrate 9 and the holding portion 25 after the adsorption is completed.

[0069] In addition, in the drawing device 1, by adjusting the setting value of the pressure reducing unit 8 for each model of the substrate 9, it is also possible to suppress the situation where the suction force per unit area of ​​the substrate 9 is different depending on the size of the substrate 9 and the presence of the through hole of the substrate 9. Thus, even if the model of the substrate 9 is different, the influence of the suction on the substrate 9, that is, the adsorption condition of the substrate 9 near the suction hole 71 can be made the same or similar. In particular, in the case where the substrate 9 has a resist layer on both the upper and lower surfaces, it is possible to suppress the state of the suction mark generated at the part of the resist layer that contacts the periphery of the suction hole 71 from changing depending on the model of the substrate 9.

[0070] In addition, to be precise, the force of the holding portion 25 to attract the substrate 9 changes with time from the start of attraction to the completion of adsorption. That is, in the exhaust fan unit, the attraction force changes according to the flow rate. The "adjustment of the force to attract the substrate 9" in the above description refers to increasing or decreasing the attraction force, i.e., the pressure reduction force, that changes according to the flow rate as a whole. In other words, "adjustment of the attraction force" refers to increasing or decreasing the attraction force at any flow rate (including the case where the flow rate is 0).

[0071] In the drawing device 1, the holding force of the substrate 9, that is, the force of the holding portion 25 to attract the substrate 9, can also be feedback-controlled at the moment when the holding of the substrate 9 is completed. Figure 7 A plurality of target pressures corresponding to the model of the substrate 9 are prepared in the storage section 62 shown, and the target pressure corresponding to the model of the predetermined substrate 9 to be held is input into the suction adjustment section 61. Furthermore, in the above-mentioned action, the on-off valve 83 is opened, and the pressure of the lower space 754 (i.e., the internal space pressure of the holding section 25) obtained by the pressure gauge 756 at the same time as the adsorption is completed is repeatedly input into the suction adjustment section 61, and the suction adjustment section 61 performs feedback control on the decompression section 8 so that the pressure of the lower space 754 becomes the target pressure corresponding to the model of the substrate 9 held by the holding section 25. Figure 6In the case of the structure, the suction force of the holding portion 25 is feedback-controlled by controlling the opening of the pressure reducing regulating valve 84 by the suction regulating portion 61. To be precise, the "suction force" of the holding portion 25 refers to the suction force of 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.

[0072] The pressure of the lower space 754 obtained by the pressure gauge 756 is the pressure of the internal space of the holding part 25 connected to the plurality of suction holes 71. The internal space here refers to the decompressed space inside the holding part 25 for suction.

[0073] By performing feedback control corresponding to the type of substrate 9, even if the type of substrate 9 is different, the substrate 9 can be appropriately held. In addition, it is possible to suppress the suction force per unit area from being different depending on the type of substrate 9.

[0074] In the above-mentioned operation example of performing feedback control after adsorption of the substrate 9, as the set values ​​of the operation of the decompression section 8, there are the opening degree of the decompression regulating valve 84 from the time when the adsorption of the substrate 9 is started to the time when the adsorption is completed (the first set value) and the target pressure of the lower space 754 applied to the feedback control from the time when the adsorption of the substrate 9 is completed (the second set value). However, various set values ​​can be adopted as the first set value of the operation of the decompression section 8 from the time when the adsorption of the substrate 9 is started to the time when the adsorption is completed (hereinafter referred to as the "first decompression operation") and the second set value of the operation of the decompression section 8 applied from the time when the adsorption of the substrate 9 is completed (hereinafter referred to as the "second decompression operation"). In addition, the time of "completion of adsorption" refers to the time when the adsorption force of the holding section 25 holding the substrate 9 reaches a predetermined value.

[0075] As a first decompression action, the suction adjustment unit 61 may also perform feedback control on the decompression unit 8 so that the pressure of the internal space of the holding unit 25 becomes a target pressure corresponding to the model of the substrate 9. Specifically, the ideal target pressure of the lower space 754 from the start of the suction of the substrate 9 to the moment of completion of the suction (the target pressure at the moment of completion of the suction, or the target pressure that changes with time from the start of the 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 is feedback controlled based on the pressure obtained by the pressure gauge 756 so that the pressure changes with the target pressure. Thus, the temporal change of the contact state between the holding surface 251 of the holding unit 25 and the substrate 9 at the moment when the substrate 9 is adsorbed is adjusted, so that the substrate 9 is properly held.

[0076] On the other hand, as the second decompression operation, feedback control may not be performed. Specifically, an ideal opening of the decompression regulating valve 84 may be obtained in advance for each model of the substrate 9 and prepared in the storage unit 62 as a second set value, and the opening corresponding to the model of the substrate 9 is input to the suction regulating unit 61. After the adsorption of the substrate 9 is completed, the opening of the decompression regulating valve 84 is (automatically) fixed to the predetermined opening. In this way, the substrate 9 is properly held.

[0077] As described above, various actions can be performed as the first decompression action and the second decompression action, and by setting the first set value and the second set value for each model of the substrate 9, appropriate retention corresponding to the model of the substrate 9 is achieved. Generally, when the action using the first set value and the second set value is performed, the opening of the decompression regulating valve 84 of the first set value (or the opening of the decompression regulating valve 84 obtained based on the first set value) is smaller than the opening of the decompression regulating valve 84 of the second set value (or the opening of the decompression regulating valve 84 obtained based on the second set value) set for the same substrate 9. That is, the action of reducing the suction force is performed at the moment when the adsorption of the substrate 9 is completed.

[0078] In addition, the first set value may be determined for each model of the substrate 9 so that the change in the suction force from the start of suction of the substrate 9 to the moment when suction is completed is similar even if the model of the substrate 9 is different, and the second set value may be determined for each model of the substrate 9 so that the suction force from the moment when suction of the substrate 9 is completed is similar even if the model of the substrate 9 is different. Thus, even if the model of the substrate 9 is different, the effect of suction on the substrate 9, that is, the adsorption condition of the substrate 9 near the suction hole 71 can be made the same or similar.

[0079] For example, when a plurality of suction marks are generated on the substrate 9 due to suction, the plurality of suction marks can be approximated without depending on the model of the substrate 9. In particular, when the substrate 9 has a resist layer on both the upper and lower surfaces, the state of the suction marks generated at the portion of the resist layer that contacts the periphery of the suction hole 71 can be suppressed from changing according to the model of the substrate 9.

[0080] In addition, if the size (size) of the substrate 9 is different, the number of suction holes 71 used for adsorption and holding is different. Therefore, in the case of adsorbing a large substrate 9, the flow rate of air introduced into the holding portion 25 from one suction hole 71 after the start of adsorption (the amount of air introduced in a specified micro time) becomes smaller than that in the case of adsorbing a small substrate. As a result, when the opening of the pressure reducing adjustment valve 84 is kept constant, the change in the adsorption condition caused by the size of the substrate 9 becomes larger. Therefore, it is particularly preferable to change the operation of the pressure reducing portion 8 for each model of the substrate 9 in the drawing device 1 that can hold substrates 9 of different sizes. Generally speaking, the larger the size of the substrate 9, the smaller the opening of the pressure reducing adjustment valve 84.

[0081] The decompression unit 8 is preferably applied to a drawing device for drawing on substrates 9 of different sizes, and therefore, it is preferably applied to a direct drawing device having such a function. That is, the decompression unit 8 is suitable for a device in which the substrate 9 moves relative to the light irradiation unit 4 while the light irradiation unit 4 (or the drawing head 41) emits modulated light to the substrate 9 held by the holding unit 25, thereby drawing a pattern on the substrate 9.

[0082] In the drawing device 1, a decompression regulating valve 84 is provided on an exhaust pipe 82 connected to an exhaust fan unit 81, and the opening of the opening connected to the external space of the decompression regulating valve 84 is adjusted by the suction regulating section 61. That is, when the suction force of the holding section 25 is adjusted, the exhaust force of the exhaust fan unit 81 is not adjusted. Thus, the decompression section 8 can be realized with a simple structure. Since it is not necessary to control the exhaust force of the exhaust fan unit 81 as a negative pressure source, that is, the output of the internal motor, a low-priced exhaust fan unit without an inverter circuit can be used as the exhaust fan unit 81. Thus, the decompression section 8 can be configured at a low cost.

[0083] The above-mentioned drawing device 1 can be modified in various ways.

[0084] For example, the internal structure of the holding portion 25 that holds the substrate 9 by sucking air from the plurality of suction holes 71 can be variously changed. The holding portion 25 can also be a dedicated holding portion for holding a substrate 9 of one size. In this case, the intermediate member 722 can be omitted. The entire holding surface 251 may not be a plane.

[0085] In the drawing device 1, the position of the holding portion 25 may be fixed, and the light irradiation portion 4 may be moved relative to the holding portion 25, thereby drawing on the substrate 9. That is, a moving mechanism is provided in the drawing device 1, and the moving mechanism moves at least one of the holding portion 25 and the light irradiation portion 4 in a direction parallel to the substrate 9 held by the holding portion 25 (that is, in a direction parallel to the upper surface 91), thereby moving the holding portion 25 relative to the light irradiation portion 4. Of course, both the holding portion 25 and the light irradiation portion 4 may be moved in a direction parallel to the substrate 9. In addition, the drawing device 1 may be a device without the stage moving mechanism 22.

[0086] The drawing device 1 is not limited to a so-called direct drawing device. The decompression section 8 for holding the substrate 9 by suction by the holding section 25 can be used in various devices for drawing a pattern on the substrate 9 by irradiating light. For example, the decompression section 8 can be used in a device for drawing a pattern on the substrate 9 by irradiating light to a mask having a pattern formed thereon and irradiating the substrate with light that has passed through the mask. In this way, as the light irradiation section 4 in the drawing device 1, various structures can be adopted for drawing a pattern on the substrate 9 by emitting light to the substrate 9 held by the holding section 25.

[0087] The substrate 9 is not limited to a substrate for a printed wiring board, and may be a glass substrate for a mask substrate or a substrate for other purposes.

[0088] The above-mentioned embodiments and the structures in the various modifications can be appropriately combined as long as they do not contradict each other.

[0089] Although the invention has been described in detail, the above description is illustrative and not restrictive, and therefore, it can be understood that many modifications and aspects can be made without departing from the scope of the invention.

Claims

1. A drawing device for drawing a pattern on a substrate by irradiating light, wherein: have: a holding portion that holds the substrate by sucking air from the plurality of suction holes; a decompression part connected to the holding part and generating a force for the holding part to attract air; A storage unit for storing a plurality of models of the substrate; a suction adjustment unit, which reads out the model of the predetermined substrate held by the holding unit from the storage unit and inputs it into the suction adjustment unit, and changes the set value of the action of the decompression unit according to the model of the substrate, thereby adjusting the force of the holding unit to attract the substrate; as well as The light irradiation unit draws a pattern on the substrate by emitting light toward the substrate held by the holding unit.

2. The drawing device according to claim 1, wherein: The holding portion can hold the substrate by selectively sucking air from the plurality of suction holes according to the size of the substrate.

3. The drawing device according to claim 1, wherein: The substrate held by the holding portion has resist layers on both surfaces.

4. The drawing device according to claim 1, wherein: The decompression unit has: Exhaust fan unit; an exhaust duct connecting the exhaust fan unit and the holding portion; and The pressure reducing regulating valve is provided in the exhaust pipe and adjusts the opening degree of the opening connected to the external space by the suction regulating part.

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

6. The drawing device according to claim 1, wherein: The holding portion has a pressure gauge, and the pressure gauge obtains the pressure of the internal space connected to the plurality of suction holes. The internal space pressure acquired by the pressure gauge is input to the suction adjustment unit. The suction adjustment section performs feedback control on the decompression section so that the pressure in the internal space becomes a target pressure corresponding to a type of a predetermined substrate held by the holding section.

7. The drawing device according to claim 1, wherein: As the set values ​​for the operation of the decompression unit, there are a first set value applied from the start of suction of the substrate to the time when suction is completed, and a second set value applied from the time when suction of the substrate is completed.

8. The drawing device according to any one of claims 1 to 7, wherein: The drawing device further includes a moving mechanism that moves at least one of the holding portion and the light irradiation portion in a direction parallel to the substrate held by the holding portion, thereby moving the holding portion relative to the light irradiation portion. The light irradiation unit includes a drawing head, and the drawing head emits modulated light toward the substrate held by the holding unit. The moving mechanism moves the substrate held by the holding unit relative to the light irradiation unit while the drawing head emits the modulated light, thereby drawing a pattern on the substrate.

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