CN119668043A - Drawing device - Google Patents

Abstract

A drawing device for drawing a pattern on a substrate by irradiation with light includes a holding unit (25) for holding the substrate by sucking air from a plurality of suction holes, a pressure reducing unit (8) for generating a force by which the holding unit (25) sucks air, a storage unit (62) for storing a plurality of types of the substrate, and a suction adjusting unit (61) for adjusting the force by which the holding unit (25) absorbs the substrate by changing a set value of the operation of the pressure reducing unit (8) according to the type of the substrate.

Description

Drawing device

[ Reference to related applications ]

The present application claims the benefit of priority of japanese patent application JP2023-154058 filed on month 21 of 2023 and the entire disclosure of this application is incorporated herein.

Technical Field

The present invention relates to a drawing device for drawing a pattern on a substrate by irradiation with light.

Background

Conventionally, in drawing a pattern on a printed board, a semiconductor board, or the like (hereinafter, referred to as a "substrate"), a drawing device is used that irradiates a photosensitive material formed on the substrate with light to draw a pattern on the photosensitive material. In such a drawing device, the substrate may be held by sucking air from a suction hole provided in the holding portion.

For example, in an exposure apparatus (drawing apparatus) disclosed in japanese patent application laid-open No. 2011-191755 (document 1), a workpiece chuck holding a substrate holds the substrate by vacuum suction. The workpiece chuck has a central suction region, an annular suction region surrounding the outer side of the central suction region, and three suction regions located outside the annular suction region. Each adsorption region is divided by a partition wall and a peripheral wall portion. In addition, a plurality of protrusions having the same height as the partition wall are provided in each adsorption region. In order to suppress the deflection of the substrate, the air conditioner connected to each suction area is adjusted according to the area of each suction area, and the pressure in each suction area is thereby made substantially constant.

However, in the drawing device, when a plurality of substrates of different types can be held, the sizes of the substrates are different and the positions of the holes in the substrates are different depending on the types. Therefore, when the substrate is simply sucked, the suction force varies depending on the type of the substrate, and the contact state between the substrate and the holding portion from the start of suction to the completion of suction or the contact state after suction varies depending on the type. As a result, the attraction may have an undesirable effect on the substrate when the substrate of a specific model is held.

Disclosure of Invention

The purpose of the present invention is to properly hold a plurality of types of substrates in a drawing device.

A drawing device according to embodiment 1 of the present invention is a drawing device for drawing a pattern on a substrate by irradiation of light, comprising a holding unit for holding the substrate by sucking air from a plurality of suction holes, a pressure reducing unit connected to the holding unit for generating a force for sucking air from the holding unit, a storage unit for storing a plurality of types of substrates, a suction adjusting unit for reading out the types of a predetermined substrate held by the holding unit from the storage unit and inputting the types of the predetermined substrate to the suction adjusting unit, and adjusting a force for sucking the substrate by the holding unit by changing a set value of an operation of the pressure reducing unit according to the types of the substrate, and a light irradiation unit for drawing the pattern on the substrate by emitting light to the substrate held by the holding unit.

According to embodiment 1 of the present invention, a plurality of types of substrates can be held appropriately in the drawing device.

In the drawing device according to claim 2 of the present invention, the holding portion can selectively suck air from the plurality of suction holes according to the size of the substrate to hold the substrate.

In aspect 3 of the present invention, in the drawing device of aspect 1 (or aspect 1 or 2), the substrate held by the holding portion has resist layers on both surfaces.

In the drawing device according to embodiment 1 (any one of embodiments 1 to 3), the pressure reducing unit includes an exhaust fan unit, an exhaust pipe connecting the exhaust fan unit and the holding unit, and a pressure reducing adjustment valve provided in the exhaust pipe, and the suction adjustment unit adjusts the opening of an opening connected to an external space.

In the drawing device according to claim 4, according to claim 5 of the present invention, the exhaust fan unit does not include an inverter circuit.

In a drawing device according to claim 6 of the present invention, in the drawing device according to claim 1 (any one of claims 1 to 5), the holding unit includes a pressure gauge that acquires an internal space pressure connected to the plurality of suction holes, the internal space pressure acquired by the pressure gauge is input to the suction adjustment unit, and the suction adjustment unit performs feedback control on the pressure reduction unit so that the internal space pressure becomes a target pressure corresponding to a model of a predetermined substrate held by the holding unit.

In a mode 7 of the present invention, in the drawing device of mode 1 (any one of modes 1 to 6 may be adopted), as the set value of the operation of the pressure reducing portion, there are a first set value from the start of suction of the substrate to the time when the suction is completed and a second set value applied from the time when the suction of the substrate is completed.

In accordance with an aspect 8 of the present invention, in the drawing device according to any one of aspects 1 to 7, 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 relatively moving the holding portion with respect to the light irradiation portion, the light irradiation portion includes a drawing head that emits modulated light to the substrate held by the holding portion, and the moving mechanism relatively moves the substrate held by the holding portion with respect to the light irradiation portion while the drawing head emits the modulated light, thereby drawing a pattern on the substrate.

The above and other objects, features, aspects and advantages will become more apparent from the following detailed description of the present invention, which is to be read in connection with the accompanying drawings.

Drawings

Fig. 1 is a perspective view showing a drawing device.

Fig. 2 is a plan view of the holding portion.

Fig. 3 is a longitudinal sectional view of the holding portion.

Fig. 4 is a top view of the intermediate member.

Fig. 5 is a top view of the lower member.

Fig. 6 is a diagram showing a structure of the pressure reducing portion.

Fig. 7 is a block diagram showing the configuration of the suction adjusting section and the periphery thereof.

Description of the reference numerals:

1. Drawing device

4. Light irradiation part

8. Pressure reducing part

9. Substrate board

22. Objective table moving mechanism

25. Holding part

41. Drawing head

61. Suction adjusting part

62. Storage unit

71. Suction hole

81. Exhaust fan unit

82. Exhaust pipe

84. Pressure reducing regulating valve

756. Pressure gauge

Detailed Description

Fig. 1 is a perspective view showing a drawing device 1 according to an embodiment of the present invention. The drawing device 1 irradiates the light of a substantially beam shape after spatial modulation to a photosensitive material forming the upper surface of the substrate 9. Then, the irradiation region of the light is scanned over the substrate 9 to draw a pattern. The drawing device 1 is a so-called direct drawing device. In fig. 1, three directions orthogonal to each other are indicated by arrows as an X direction, a Y direction, and a Z direction. The X direction and the Y direction are horizontal directions perpendicular to each other, and the Z direction is vertical direction (i.e., up-down direction). The same applies to the other figures.

The substrate 9 is, for example, a substrate for manufacturing a printed wiring board having a substantially rectangular flat plate shape. On a 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 (i.e., an image forming a circuit pattern) is drawn on the resist film of the substrate 9. The type and shape of the substrate 9 may be variously changed.

The drawing device 1 includes a stage 21, a stage moving mechanism 22, an alignment section 3, and a light irradiation section 4. The stage 21 is a substantially rectangular flat plate-like member disposed below (i.e., -Z) the alignment portion 3 and the light irradiation portion 4. The stage 21 has a holding portion 25 for holding the substrate 9 in a horizontal state from below. The holding portion 25 is a vacuum chuck that holds the lower surface of the substrate 9 by suction. The upper surface 91 of the substrate 9 mounted on the holding portion 25 is substantially perpendicular to the Z direction and substantially parallel to the X direction and the Y direction.

The drawing device 1 also has a pressure reducing portion that generates a force that the holding portion 25 attracts air, but the illustration is omitted in fig. 1.

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 a horizontal direction (i.e., a direction substantially parallel to the upper surface 91 of the substrate 9). The stage moving mechanism 22 is attached to the upper surface of the base 11, and is supported from below by the base 11. 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 lower side, and moves the stage 21 linearly along the guide rail in the X direction. The first moving mechanism 23 supports the second moving mechanism 24 from the lower side, and moves the stage 21 linearly along the guide rail in the Y direction 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, linear servo motors or driving sources in which motors are mounted on ball screws. The structures of the first moving mechanism 23 and the second moving mechanism 24 may be variously changed.

The drawing device 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 device 1 may be provided with a stage lifting mechanism for moving the stage 21 in the Z direction. As the stage rotation mechanism, for example, a servo motor can be used. As the stage lifting mechanism, for example, a linear servo motor can be used. The structures of the stage rotation mechanism and the stage lifting mechanism may be variously changed.

The alignment part 3 has 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 illustrated. Each alignment camera 31 is supported above the stage 21 and the stage moving mechanism 22 by a support 40 provided across the stage 21 and the stage moving mechanism 22. In the example shown in fig. 1, the support 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 from the upper surface of the base 11.

In the example shown in fig. 1, two alignment cameras 31 are mounted on the (+y) -side surface of the support portion 40. One of the two alignment cameras 31, for example, one alignment camera 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. This allows the distance in the X direction between the two alignment cameras 31 to be changed. The number of alignment cameras 31 of the alignment unit 3 may be one or three or more.

Each alignment camera 31 photographs an alignment mark (not shown) provided in advance on the upper surface 91 of the substrate 9. In the drawing apparatus 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.

The light irradiation section 4 has a plurality of (six in the example shown in fig. 1) drawing heads 41 arranged in the X direction. The plurality of drawing heads 41 have substantially the same structure. Each drawing head 41 has a spatial light modulator, 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 moving mechanism 22 by the support 40. In the example shown in fig. 1, six drawing heads 41 are attached to the support portion 40.

The six drawing heads 41 are arranged substantially linearly in parallel with the X direction. The positions of the six drawing heads 41 in the Y direction and the Z direction are substantially the same. The plurality of drawing heads 41 may not be aligned in a straight line, but may be arranged in a staggered manner, for example. In the light irradiation unit 4, the number of drawing heads 41 may be one or two or more.

In the drawing device 1, the pattern drawing on the substrate 9 is performed in a so-called multi-path system. Specifically, the modulated light is irradiated onto the upper surface 91 of the substrate 9 from the plurality of drawing heads 41 of the light irradiation section 4, and the substrate 9 is moved in the Y direction by the first movement mechanism 23 of the stage movement mechanism 22 to pass under the drawing heads 41. Thus, the irradiation region of the light from the plurality of drawing heads 41 is scanned in the Y direction over the substrate 9, and drawing is performed on the substrate 9. In this way, while each drawing head 41 emits modulated light to the substrate 9 held by the holding portion 25, the substrate 9 moves relatively to the light irradiation portion 4, and a pattern is drawn on the substrate 9.

Next, the substrate 9 is moved stepwise in the X direction by a predetermined distance by the second moving mechanism 24. Then, the substrate 9 is again moved in the Y direction by the first moving mechanism 23, and light is irradiated from the drawing head 41 to the substrate 9 in parallel with the movement, whereby drawing on the substrate 9 is performed. In the drawing device 1, the irradiation of light to the substrate 9 moving in the Y direction and the stepwise movement of the substrate 9 in the X direction are alternately performed, whereby the pattern is drawn on the substrate 9.

In the following description, the Y direction is referred to as a "main scanning direction" or simply as a "scanning direction", and the X direction is referred to as a "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.

In the drawing device 1, the substrate 9 may be drawn by 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 relative to the drawing head 41 only once in the Y direction. In this case, the sub-scanning (i.e., the stepwise movement in the X direction) of the substrate 9 by the second movement mechanism 24 is not performed at the time of drawing the pattern. That is, the stage moving mechanism 22 is a scanning mechanism that moves the stage 21 at least in the scanning direction with respect to the drawing head 41.

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 for holding the substrate 9. The holding surface 251 is provided with a plurality of suction holes 71. The suction holes 71 are arranged in the X-direction and the Y-direction so as to extend in two dimensions on the holding surface 251. Each suction hole 71 is a minute hole.

Fig. 3 is a longitudinal sectional view of the holding portion 25. In fig. 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-like 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 portion 734 and a wall portion 735. The wall 735 extends upward from the bottom 734.

Fig. 4 is a top view of intermediate member 722. The cross-section of fig. 3 shows a section at the location 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, 743. The partition 742 is L-shaped and forms a small partition 751 together with the peripheral wall 741. The partition 743 is also L-shaped and is located outside the partition 751. A partition 752 is formed between the partition 742 and the partition 743 by the outer peripheral wall 741 and the partitions 742 and 743. Partition 752 is an L-shaped partition circumscribing partition 751. An L-shaped partition 753 is formed by the peripheral wall 741 and the partition 743 and circumscribes the partition 752.

At least one switching valve 733 is arranged in each of the partitions 751, 752, 753. As the switching valve 733, for example, a solenoid valve is used. Each of the switching valves 733 switches between an open state and a closed state. When the switching valve 733 is in the closed state, air cannot pass through the bottom 731 up and down at the position of the switching valve 733. With the switching valve 733 in an open state, 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 are in contact with the lower surface of the upper plate 721 (see fig. 3), and the space between the upper plate 721 and the wall 732 is sealed so that air cannot pass therethrough. The upper plate 721 contacts the intermediate member 722, and thus the partitions 751 to 753 are surrounded by a space in the up-down direction and the horizontal direction.

Fig. 5 is a top 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 735 contacts the lower surface of the bottom 731 of the intermediate member 722 (see fig. 3), and the space between the bottom 731 and the wall 735 is sealed so that air cannot pass through. By the contact between the bottom 731 and the lower member 723, a lower space 754 surrounded in the vertical and horizontal directions is formed by the bottom 731, the wall 735, and the bottom 734. An exhaust pipe 82 for exhausting air is connected to the bottom 734. A pressure gauge 756 for acquiring the pressure in the lower space 754 is provided in the lower space 754.

Fig. 6 is a diagram showing the structure of the pressure reducing portion 8 connected to the holding portion 25. The pressure reducing portion 8 generates a force with which the holding portion 25 attracts air. The pressure reducing portion 8 includes an exhaust fan unit 81, an exhaust pipe 82, an on-off valve 83, and a pressure reducing adjustment valve 84. The exhaust fan unit 81 is a device that rotates an impeller by a motor to perform exhaust, and is referred to as a blower, for example. The exhaust fan unit 81 is a reduced pressure source. The exhaust duct 82 connects the exhaust fan unit 81 and the holding portion 25 (see fig. 3). The exhaust pipe 82 has flexibility and deforms following the movement of the stage 21 including the holding portion 25.

The opening/closing valve 83 is a valve that switches between an open state and a closed state. As the opening/closing valve 83, for example, an electromagnetic valve is used. The pressure reducing valve 84 is provided in the exhaust pipe 82. The pressure reducing and adjusting valve 84 is an electrically operated valve whose opening degree can be changed according to an electric signal. The opening degree of the opening connecting the exhaust pipe 82 and the external space is adjusted by the pressure reducing adjustment valve 84. Thereby, the force with which the holding portion 25 attracts the substrate 9 is adjusted. That is, when the opening degree of the pressure reducing adjustment valve 84 increases, the outside air flows into the exhaust pipe 82, the pressure reducing state in the exhaust pipe 82 is relaxed, and the suction force in the holding portion 25 decreases.

Fig. 7 is a block diagram showing the configuration of the suction adjusting portion 61 and its periphery for adjusting the suction of air by the holding portion 25. The suction adjusting unit 61 is implemented by a computer (i.e., a general-purpose computing device operated by a program) or a dedicated computing circuit. The suction adjusting unit 61 may be implemented by combining a computer with a dedicated arithmetic circuit. The suction adjusting 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 a plurality of types of the board 9. The "model" of the substrate 9 refers to information for determining the size of the substrate 9, determining the position and/or size thereof in the case where a through hole is present, and the like, for example, a product number.

The overall control unit 60 shown in fig. 7 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 by a program) or a dedicated computing circuit. The overall control unit 60 may be implemented by combining a computer with a dedicated arithmetic circuit. The functions of the suction adjusting unit 61 and the storage unit 62 may be included in the overall control unit 60. In fig. 7, the overall control unit 60 also controls the operation timing of the attraction adjusting unit 61, the stage moving mechanism 22, the alignment unit 3, the light irradiation unit 4, and the like, as well as the operation of the light irradiation unit 4.

Next, an operation of the holding portion 25 for holding the substrate 9 will be described. In a stage before the holding portion 25 holds the substrate 9, the exhaust fan unit 81 is driven in a state where the opening/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. To be precise, information indicating the model of the substrate 9 is input to the suction adjusting section 61. The suction adjusting unit 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 reducing adjusting valve 84.

Specifically, in the holding portion 25 shown in fig. 2 to 5, the substrate 9 of the size of the partition 751 in fig. 4 (hereinafter, referred to as "small-sized substrate 9"), the substrate 9 of the size of the partition 751 and the partition 752 together (hereinafter, referred to as "medium-sized substrate 9"), and the substrate 9 of the size of the partition 751 to the partition 753 together (hereinafter, referred to as "large-sized substrate 9") can be held. When the holding portion 25 holds the small-sized substrate 9, only the switching valve 733 in the partition 751 is opened by the suction adjusting portion 61, and the other switching valves 733 are closed. The suction adjusting unit 61 controls the pressure reducing adjusting valve 84 to have an opening corresponding to the type of the substrate 9 to be held.

In parallel with the above-described operation or before or after the above-described operation, the small-sized substrate 9 is placed in a region corresponding to the partition 751 of the holding surface 251 of fig. 2. Then, by the control of the overall control unit 60, the on-off valve 83 is opened, and the exhaust pipe 82, the lower space 754, and the partition 751 are depressurized, and suction is performed from the suction hole 71 in the partition 751. Thereby, 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 holes 71 overlapping with the small-sized substrates 9.

In the above-described operation of holding the medium-sized substrate 9 by the holding portion 25, the operation is performed based on the operation of holding the small-sized substrate 9, except that the switching valves 733 of the partitions 751 and 752 are opened and the other switching valves 733 are closed. In the above-described operation of holding the large-sized substrate 9 by the holding portion 25, the operation based on the operation of holding the small-sized substrate 9 is performed except for the point that the switching valves 733 of all the partitions 751 to 753 are opened. In this way, in the holding portion 25, the air can be selectively sucked from only the plurality of suction holes 71 overlapping the substrate 9 to hold the substrate 9 in accordance with the size of the substrate 9.

As described above, when the holding unit 25 holds the substrate 9, the predetermined type of the substrate 9 held by the holding unit 25 is read out (automatically) from the storage unit 62 and input to the suction adjustment unit 61, and the opening degree of the pressure reducing adjustment valve 84, which is a set value for the operation of the pressure reducing unit 8, is changed (automatically) according to the type of the substrate 9, so that the force with which the holding unit 25 sucks the substrate 9 is adjusted. Further, "automatically" means not via a direct operation by the operator. This makes it possible to set the conditions for adsorbing the substrate 9 to appropriate conditions, and to achieve appropriate holding according to the type of the substrate 9. That is, in the drawing device 1, a plurality of types of substrates can be held appropriately. The "adsorption condition" refers to a 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 a contact state between the substrate 9 and the holding portion 25 after the completion of adsorption.

In the drawing device 1, by adjusting the set value of the pressure reducing unit 8 for each model of the board 9, it is possible to suppress the suction force per unit area to the board 9 from being different depending on the size of the board 9 and the presence of the through hole of the board 9. Thus, even if the types of the substrates 9 are different, the influence of suction on the substrates 9, that is, the suction conditions of the substrates 9 in the vicinity of the suction holes 71 can be made the same or similar. In particular, in the case where the substrate 9 has the resist layers on the upper and lower surfaces, the state of the suction mark generated at the portion of the resist layer in contact with the periphery of the suction hole 71 can be suppressed from changing depending on the type of the substrate 9.

In addition, precisely, the force with which the holding portion 25 attracts the substrate 9 varies with time from the start of suction to the completion of suction. That is, in the exhaust fan unit, the suction force varies according to the flow rate. In the above description, "adjusting the force of sucking the substrate 9" means to increase or decrease the suction force, that is, the pressure reducing force, as a whole in accordance with the flow rate change. In other words, "adjustment of the attractive force" means increasing or decreasing the attractive force at an arbitrary flow rate (including the case where the flow rate is 0).

In the drawing device 1, the holding force of the substrate 9, that is, the force with which the holding portion 25 attracts the substrate 9 may be feedback-controlled at the time when the holding of the substrate 9 is completed. Specifically, a plurality of target pressures corresponding to the model of the substrate 9 are prepared in advance in the storage unit 62 shown in fig. 7, and the target pressures corresponding to the model of the predetermined substrate 9 to be held are input to the suction adjustment unit 61. In the above operation, the on-off valve 83 is opened, and the pressure in the lower space 754 (i.e., the internal space pressure of the holding portion 25) obtained by the pressure gauge 756 is repeatedly input to the suction adjusting portion 61 while the suction is completed, and the suction adjusting portion 61 performs feedback control on the pressure reducing portion 8 so that the pressure in the lower space 754 becomes a target pressure corresponding to the type of the substrate 9 held by the holding portion 25. In the case of the configuration of fig. 6, the suction force of the holding portion 25 is feedback-controlled by controlling the opening degree of the pressure reducing adjustment valve 84 by the suction adjustment portion 61. To be precise, "attraction force" of the holding portion 25 refers to attraction force of the holding portion 25 per unit area of the substrate 9, and the description of attraction force of the holding portion 25 is also similar to that described below.

The pressure in the lower space 754 obtained by the pressure gauge 756 is the internal space pressure of the holding portion 25 connected to the plurality of suction holes 71. The internal space here is a depressurized space for suction, among the internal spaces of the holding portion 25.

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

In the above-described operation example in which feedback control is performed after the substrate 9 is suctioned, there are an opening degree (first set value) of the pressure reducing adjustment valve 84 from the time when suction of the substrate 9 is started to the time when suction is completed, and a target pressure (second set value) applied to the lower space 754 of feedback control from the time when suction of the substrate 9 is completed, as set values of the operation of the pressure reducing unit 8. However, various setting values may be used as a first setting value of the operation of the pressure reducing section 8 (hereinafter, referred to as "first pressure reducing operation") from the time when the suction of the substrate 9 is started to the time when the suction is completed, and as a second setting value of the operation of the pressure reducing section 8 (hereinafter, referred to as "second pressure reducing operation") applied from the time when the suction of the substrate 9 is completed. The time when the suction is completed is a time when the suction force of the substrate 9 held by the holding portion 25 reaches a predetermined level.

As the first depressurizing operation, the suction adjusting unit 61 may perform feedback control on the depressurizing 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, a desired target pressure (target pressure at the time of suction completion or target pressure that varies with time from the start of suction) of the lower space 754 from the time of starting suction of the substrate 9 to the time of completion of suction may be input as a first set value from the storage unit 62 to the suction adjustment unit 61, and the pressure of the pressure reducing adjustment valve 84 may be feedback-controlled based on the pressure acquired by the pressure gauge 756 so as to vary with the target pressure. Thus, the temporal change in the contact state between the holding surface 251 of the holding portion 25 and the substrate 9, which is the moment when the holding portion 25 adsorbs the substrate 9, is adjusted, and the substrate 9 is held appropriately.

On the other hand, the feedback control may not be performed as the second depressurizing operation. Specifically, the opening degree of the pressure reducing valve 84 may be obtained in advance for each model of the substrate 9, and the opening degree corresponding to the model of the substrate 9 may be input to the suction adjusting unit 61 as the second set value in the storage unit 62, and after the adsorption of the substrate 9 is completed, the opening degree of the pressure reducing valve 84 may be (automatically) fixed to a predetermined opening degree. Thereby, proper holding of the substrate 9 is achieved.

As described above, various operations are possible as the first depressurizing operation and the second depressurizing operation, and the first setting value and the second setting value are set for each model of the substrate 9, thereby realizing appropriate holding according to the model of the substrate 9. In general, when the operation using the first set value and the second set value is performed, the opening degree of the pressure reducing adjustment valve 84 of the first set value (or obtained based on the first set value) is smaller than the opening degree of the pressure reducing adjustment valve 84 of the second set value (or obtained based on the second set value) set for the same substrate 9. That is, the suction force is reduced at the instant when the suction of the substrate 9 is completed.

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 the suction of the substrate 9 to the time of the completion of the suction 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 time of the completion of the suction of the substrate 9 is similar even if the model of the substrate 9 is different. Thus, even if the types of the substrates 9 are different, the influence of suction on the substrates 9, that is, the suction conditions of the substrates 9 in the vicinity of the suction holes 71 can be made the same or similar.

For example, when a plurality of suction marks are generated on the substrate 9 by suction, the plurality of suction marks can be approximated independently of the type of the substrate 9. In particular, in the case where the substrate 9 has the resist layers on the upper and lower surfaces, the state of the suction mark generated at the portion of the resist layer in contact with the periphery of the suction hole 71 can be suppressed from changing depending on the type of the substrate 9.

Further, since the number of suction holes 71 for suction holding is different when the size (size) of the substrate 9 is different, in the case of the large substrate 9, the flow rate of the air introduced from one suction hole 71 into the holding portion 25 (the amount of air introduced in a predetermined minute time) immediately after the start of suction is smaller than in the case of the small substrate. As a result, when the opening degree of the pressure reducing adjustment valve 84 is made constant, the variation in the adsorption condition according to the size of the substrate 9 becomes large. Therefore, the operation of the pressure reducing portion 8 is changed for each model of the substrate 9, and is particularly preferably applied to the drawing device 1 capable of holding substrates 9 of different sizes. In general, the larger the size of the substrate 9, the smaller the opening degree of the opening of the pressure reducing adjustment valve 84.

The pressure reducing portion 8 is preferably applied to a drawing device that draws a substrate 9 of a different size, and therefore, the pressure reducing portion 8 is preferably applied to a direct drawing device having such a function. That is, the pressure reducing section 8 is suitable for a device in which the substrate 9 is moved relatively to the light irradiation section 4 to draw a pattern on the substrate 9 while the light irradiation section 4 (or the drawing head 41) emits the modulated light to the substrate 9 held by the holding section 25.

In the drawing device 1, a decompression adjustment valve 84 is provided in an exhaust pipe 82 connected to an exhaust fan unit 81, and the suction adjustment unit 61 adjusts the opening of an opening connected to the external space of the decompression adjustment valve 84. That is, when the suction force of the holding portion 25 is adjusted, the exhaust force of the exhaust fan unit 81 is not adjusted. This makes it possible to realize the pressure reducing section 8 with a simple configuration. 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. This makes it possible to construct the pressure reducing portion 8 at low cost.

The drawing device 1 may be variously modified.

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

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, the drawing device 1 is provided with a moving mechanism that 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 (i.e., in a direction parallel to the upper surface 91), thereby relatively moving the holding portion 25 with respect 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. The drawing device 1 may be a device in which the stage moving mechanism 22 is not present.

The drawing device 1 is not limited to the so-called direct drawing device. The pressure reducing portion 8 for holding the substrate 9 by the holding portion 25 can be used for various devices for drawing a pattern on the substrate 9 by irradiation of light. For example, the pressure reducing unit 8 can be used for a device that irradiates light to a mask having a pattern formed thereon, irradiates light that has passed through the mask to a substrate, and draws a pattern on the substrate 9. As described above, as the light irradiation section 4 in the drawing device 1, various configurations can be adopted in which a pattern is drawn on the substrate 9 by emitting light to the substrate 9 held by the holding section 25.

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.

The above-described embodiments and the configurations in the respective modifications may be appropriately combined as long as they do not contradict each other.

Although the invention has been described in detail, the foregoing description is illustrative and not restrictive. Accordingly, it can be said that various modifications and modes can be made without departing from the scope of the invention.

Claims (8)

1. A drawing device for drawing a pattern on a substrate by irradiation of light, wherein,

The device comprises:

a holding unit that holds the substrate by sucking air from the plurality of suction holes;

a pressure reducing unit connected to the holding unit and generating a force for sucking air by the holding unit;

A storage unit for storing a plurality of types of substrates;

A suction adjusting portion for reading out a model of a predetermined substrate held by the holding portion from the storage portion and inputting the model to the suction adjusting portion, and changing a set value of an operation of the pressure reducing portion according to the model of the substrate, thereby adjusting a force with which the holding portion sucks the substrate, and

And a light irradiation unit that irradiates light onto the substrate held by the holding unit, thereby drawing a pattern on the substrate.

2. The drawing device according to claim 1, wherein,

The holding portion is capable of selectively sucking air from the plurality of suction holes according to a size of a substrate to hold the substrate.

3. The drawing device according to claim 1, wherein,

The substrate held by the holding portion has resist layers on both sides.

4. The drawing device according to claim 1, wherein,

The pressure reducing unit has:

An exhaust fan unit;

An exhaust duct connecting the exhaust fan unit and the holding portion, and

And a pressure reducing adjustment valve provided in the exhaust pipe, the opening of the opening connected to the external space being adjusted by the suction adjustment unit.

5. The drawing device according to claim 4, wherein,

The exhaust fan unit has no inverter circuit.

6. The drawing device according to claim 1, wherein,

The holding part is provided with a pressure gauge which acquires the pressure of the inner space connected with the plurality of suction holes,

The internal space pressure acquired by the pressure gauge is input to the suction adjusting section,

The suction adjusting unit performs feedback control on the pressure reducing unit so that the internal space pressure becomes a target pressure corresponding to a predetermined type of the substrate held by the holding unit.

7. The drawing device according to claim 1, wherein,

As the set values of the operation of the pressure reducing section, there are a first set value from the start of the suction of the substrate to the time of the completion of the suction and a second set value applied from the time of the completion of the suction of the substrate.

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 relatively moving the holding portion with respect to the light irradiation portion,

The light irradiation section has a drawing head which emits modulated light toward the substrate held by the holding section,

The moving mechanism moves the substrate held by the holding portion relative to the light irradiation portion while the drawing head emits the modulated light, thereby drawing a pattern on the substrate.