Direct-drawing exposure apparatus and exposure method

Abstract

To provide a direct-drawing exposure apparatus and exposure method that enable high-quality exposure processing. [Solution] The direct-draw exposure apparatus irradiates the illumination surface with exposure light while transporting the substrate in a first direction parallel to the illumination surface. The substrate is placed on the stage. Each exposure head irradiates the illumination surface with exposure light. A moving mechanism moves the stage in the first direction and in a second direction perpendicular to the illumination surface. An autofocus module is provided on at least one of the exposure heads and has a tracking range. A first rangefinder measures the exposure distance in a second direction between the exposure head and the illumination surface and has a first measurement range wider than the tracking range. A second rangefinder measures the exposure distance and has a second measurement range wider than the first measurement range. A controller determines whether the exposure distance exceeds the first measurement range based on the distance measured by the first rangefinder and the distance measured by the second rangefinder.

Description

[Technical Field]

[0001] The present invention relates to a direct-drawing exposure apparatus and an exposure method. [Background Art]

[0002] In the image recording system described in Patent Document 1, when focus adjustment by a prism pair cannot be performed because the shape of the exposure surface changes greatly or abruptly, a process of blunting the waveform of displacement data representing the concavo-convex shape of the exposure surface is performed. Such waveform blunting processing is repeatedly performed until it is determined that focus adjustment by the prism pair is possible. This enables exposure even if the shape of the exposure surface deviates somewhat from the standard. [Prior Art Documents] [Patent Documents]

[0003] [Patent Document 1] Japanese Patent No. 5624580 [Summary of the Invention] [Problem to be Solved by the Invention]

[0004] In such a field, there is a demand for a technology that enables high-quality exposure processing.

[0005] In view of the above circumstances, an object of the present technology is to provide a direct-drawing exposure apparatus and an exposure method that enable high-quality exposure processing. [Means for Solving the Problem]

[0006] To achieve the above object, a direct-drawing exposure apparatus according to one aspect of the present technology is a direct-drawing exposure apparatus that irradiates exposure light onto an irradiation surface of a substrate while conveying the substrate in a first direction parallel to the irradiation surface, the apparatus comprising a stage, a plurality of exposure heads, a moving mechanism, an autofocus module, a first distance meter, a second distance meter, and a controller. The substrate is placed on the aforementioned stage. Each of the exposure heads irradiates the irradiation surface with the exposure light. The moving mechanism moves the stage relative to the plurality of exposure heads in a first direction and a second direction perpendicular to the illumination surface. The autofocus module is provided on at least one of the plurality of exposure heads and adjusts the focal position of the exposure light in the second direction, and has a tracking range that is a range in which the focal position can be adjusted. The first rangefinder measures the distance between each of the multiple exposure heads and the illumination surface in the second direction and has a first measurement range that is wider than the tracking range. The second rangefinder measures the distance between each of the multiple exposure heads and the illumination surface in a second direction and has a second measurement range that is wider than the first measurement range. The controller determines, based on the distance measured by the first rangefinder and the distance measured by the second rangefinder, whether the distance between the plurality of exposure heads and the illumination surface exceeds the first measurement range.

[0007] In this direct-draw exposure system, the distance between multiple exposure heads and the illumination surface is measured by a first rangefinder having a first measurement range wider than the tracking range of the autofocus module, and a second rangefinder having a second measurement range wider than the first measurement range. Furthermore, based on the distances measured by the first and second rangefinders, it is determined whether the distance between the multiple exposure heads and the illumination surface exceeds the first measurement range. This enables high-quality exposure processing.

[0008] The plurality of exposure heads may include a first row of exposure heads and a second row of exposure heads arranged in multiple rows along a third direction parallel to the illumination surface and intersecting the first direction.

[0009] The first exposure head row and the second exposure head row may be arranged offset from each other in the third direction.

[0010] The first and second rangefinders may be positioned between the first exposure head row and the second exposure head row.

[0011] The autofocus module may be provided on each of the plurality of exposure heads.

[0012] The number of the first rangefinders may be two or more. In this case, each of the first rangefinders may be positioned along a third direction that is parallel to the illumination surface and intersects the first direction.

[0013] The first rangefinder may be provided in accordance with the plurality of exposure heads.

[0014] The number of the first rangefinders may be less than the number of the multiple exposure heads.

[0015] The number of the second rangefinders may be less than the number of the first rangefinders.

[0016] The plurality of exposure heads, the first rangefinder, and the second rangefinder may be supported by a common support.

[0017] If the controller determines that the distance between the plurality of exposure heads and the illumination surface exceeds the first measurement range, it may move the stage in the second direction based on the distance measured by the second distance meter so that the distance between the plurality of exposure heads and the illumination surface falls within the first measurement range.

[0018] If the controller determines that the distance between the plurality of exposure heads and the illumination surface is within the first measurement range, it may determine, based on the distance measured by the first distance meter, whether the distance between the plurality of exposure heads and the illumination surface exceeds the tracking range, and if it determines that the distance exceeds the tracking range, it may move the stage in the second direction, based on the distance measured by the first distance meter, so that the distance between the plurality of exposure heads and the illumination surface falls within the tracking range.

[0019] An exposure method according to one embodiment of this technology is an exposure method in which exposure light is irradiated onto the irradiation surface of a substrate while transporting the substrate in a first direction parallel to the irradiation surface of the substrate, and the method includes placing the substrate on a stage. The exposure light is irradiated onto the illumination surface by each of a plurality of exposure heads, each of which is provided with at least one autofocus module having a tracking range that is a range in which the focal position of the exposure light is adjusted in a second direction perpendicular to the illumination surface. The stage is moved in the first and second directions relative to the plurality of exposure heads. The distance between the plurality of exposure heads and the illumination surface in the second direction is measured by a first distance meter having a first measurement range wider than the aforementioned tracking range. A second distance meter having a second measurement range wider than the first measurement range measures the distance between each of the multiple exposure heads and the illumination surface in the second direction. Based on the distance measured by the first rangefinder and the distance measured by the second rangefinder, it is determined whether the distance between the plurality of exposure heads and the illumination surface exceeds the first measurement range.

[0020] When it is determined that the distance between the plurality of exposure heads and the irradiation surface exceeds the first measurement range, the stage may be moved in the second direction based on the distance measured by the second distance meter such that the distance between the plurality of exposure heads and the irradiation surface falls within the first measurement range. In this case, after the movement in the second direction is completed, the exposure light may be irradiated onto the irradiation surface by each of the plurality of exposure heads while moving the stage in the first direction. Effects of the Invention

[0021] According to the present invention, high-quality exposure processing can be achieved. Note that the effects described herein are not necessarily limited, and may be any of the effects described in the present disclosure. Brief Description of the Drawings

[0022] [Figure 1] It is a schematic diagram showing a configuration example of a direct-drawing exposure apparatus 2 according to an embodiment of the present technology. [Figure 2] It is a schematic diagram showing the arrangement of an exposure head 22 and the like. [Figure 3] It is a schematic diagram showing a measurement range and the like. [Figure 4] It is a schematic diagram showing a configuration example of a control device 13. [Figure 5] It is a flowchart showing an example of processing related to exposure. Mode for Carrying Out the Invention

[0023] Hereinafter, embodiments according to the present technology will be described with reference to the drawings.

[0024] [Direct-drawing exposure apparatus] FIG. 1 is a schematic diagram showing a configuration example of a direct-drawing exposure apparatus 2 according to an embodiment of the present technology. The direct-drawing exposure apparatus 2 includes a direct-drawing exposure machine 10, a light source unit 11, an image processing unit 12, and a control device 13.

[0025] The direct-draw exposure apparatus 2 rasterizes vector data (or Gerber data) edited using CAM (Computer-Aided Manufacturing) from a predetermined drawing pattern (e.g., a printed circuit pattern) designed with CAD (Computer-Aided Design), using an image processing unit 12. Furthermore, based on the resulting raster data (where the presence or absence of exposure recording for each pixel is represented by a binary value of "0" or "1"), the substrate 14 is exposed using the direct-draw exposure machine 10 and the light source unit 11, thereby forming the desired image on the substrate 14 without the need for a mask.

[0026] The substrate 14 is, for example, a printed circuit board or a glass substrate for a flat panel display, on which a photosensitive material is coated or attached to the exposure surface 14a. The specific type of substrate 14 is not limited. Alignment marks 15 are provided on the exposure surface 14a to indicate the reference exposure position. The alignment marks 15 are formed, for example, by the unevenness of a thin film, and are arranged one at each of the four corners of the exposure surface 14a, for a total of four marks. The exposure surface 14a corresponds to one embodiment of the irradiation surface according to this technology.

[0027] The direct-draw exposure machine 10 has a flat base 16. The base 16 is supported by four legs 17 and is arranged parallel to the horizontal plane (the XY plane shown in Figure 1). The short side of the base 16 coincides with the X direction, and the long side coincides with the Y direction.

[0028] Two guide rails 18 are provided side by side on the upper surface of the base 16, parallel to each other in the Y direction. A movable stage 19, which holds the substrate 14 by suction, is mounted on the guide rails 18 so as to be able to slide freely in the Y direction. When the substrate 14 is placed on the movable stage 19, the exposure surface 14a becomes parallel to the XY plane.

[0029] The moving stage 19 is moved back and forth in the Y direction by a moving mechanism that includes a drive source such as a linear motor. This also transports the substrate 14 in the Y direction. Although not shown in the figure, the moving stage 19 is also equipped with a moving mechanism for adjusting its position in the Z direction.

[0030] In this embodiment, the moving stage 19 does not move in the X direction or the rotational direction (the θ direction shown in Figure 1). This reduces the number of movement axes and makes it possible to reduce errors related to movement. On the other hand, movement in the X direction or the rotational direction may be possible.

[0031] The moving stage 19 corresponds to one embodiment of the stage according to this technology. The Y direction is parallel to the exposure surface 14a and corresponds to one embodiment of the first direction in which the substrate 14 is transported. The Z direction corresponds to one embodiment of a second direction perpendicular to the Y direction and the exposure surface 14a.

[0032] The exposure unit 20 is positioned approximately in the center of the base 16 in the Y direction. The exposure unit 20 is fixed to a gate-shaped first gate 21 that is erected to straddle the guide rail 18. The exposure unit 20 is equipped with a total of eight cylindrical exposure heads 22, four arranged along the X direction and two rows in the Y direction.

[0033] Between the two rows of exposure heads 22 are eight AF (Auto Focus) sensors 28 and one AF assist sensor 29. In Figure 1, the exposure heads 22, AF sensors 28, and AF assist sensor 29 are schematically illustrated with dashed lines for visibility. The exposure heads 22, AF sensors 28, and AF assist sensor 29 are supported by a common support (the housing portion of the exposure unit 20 and the first gate 21). The X direction corresponds to one embodiment of a third direction that is parallel to the exposure surface 14a and intersects the Y direction.

[0034] The exposure head 22 is connected to an optical fiber 23 drawn from the light source unit 11 and a signal cable 24 drawn from the image processing unit 12. Based on frame data (raster data divided for each exposure head 22) input from the image processing unit 12 via the signal cable 24, the exposure head 22 modulates the laser beam input from the light source unit 11 via the optical fiber 23. The modulated laser beam is then irradiated onto the irradiation surface 14a of the substrate 14, which passes directly beneath it as the moving stage 19 moves in the Y direction, to perform exposure.

[0035] More specifically, each exposure head 22 has a DMD (Digital Micromirror Device) and a predetermined optical system, and the frame data input via the signal cable 24 is written to each SRAM (Static Random Access Memory) of the DMD, thereby generating the desired exposure light emitted from the exposure head 22.

[0036] Each exposure head 22 is also provided with a pair of prisms 49. In Figure 1, only one pair of prisms 49 is schematically shown with a dashed line, but the specific shape of the pair of prisms 49 is not limited. The pair of prisms 49 can be moved in the Y direction by a drive mechanism including a drive source such as a stepping motor, and by moving the pair of prisms 49 in the Y direction, it is possible to adjust the focal position of the exposure light in the Z direction. The prism pair 49 corresponds to one embodiment of the autofocus module according to this technology.

[0037] The eight AF sensors 28 are arranged in a line along the X direction. The AF sensors 28 are laser interferometers that measure the uneven shape of the exposure surface 14a by, for example, irradiating the exposure surface 14a with laser light and receiving the reflected light at the right time. In other words, the AF sensors 28 measure the distance in the Z direction between the exposure head 22 and the exposure surface 14a (hereinafter referred to as the exposure distance).

[0038] The AF assist sensor 29 is also a sensor that measures the exposure distance. For example, a diffuse reflection type displacement sensor can be used as the AF assist sensor 29.

[0039] Furthermore, the specific types of the AF sensor 28 and AF assist sensor 29 are not limited. The measured values ​​from the AF sensor 28 and AF assist sensor 29 are output to the control device 13. The sensing light emitted from the AF sensor 28 and AF assist sensor 29 is set to an oscillation wavelength that does not expose the exposure surface 14a. The AF sensor 28 corresponds to one embodiment of the first rangefinder according to this technology. The AF assist sensor 29 corresponds to one embodiment of the second rangefinder according to this technology.

[0040] A gate-shaped second gate 25 is erected on the base 16, straddling the guide rail 18. Three cameras 27 are installed on the second gate 25 to photograph the substrate 14, which passes directly beneath it as the moving stage 19 moves in the Y direction, from above in the Z direction. The images captured by the cameras 27 are output to the control device 13. On the control device 13 side, the positional displacement of the substrate 14 in the X, Y, and θ directions is calculated based on the alignment marks 15 included in the captured images, and the raster data is corrected according to the positional displacement.

[0041] Furthermore, a pair of length measuring devices 26 are attached to one end of the base 16 in the Y direction. The length measuring devices 26 are, for example, laser displacement meters, which irradiate the side end face of the moving stage 19 with laser light to measure the position of the moving stage 19 in the Y direction. The length measurement results from the length measuring devices 26 are output to the control device 13. Note that ultrasonic transceivers or stereo cameras may be used as the length measuring devices 26. Similarly, a length measuring device for measuring the position of the moving stage 19 in the Z direction may also be provided.

[0042] [Placement of exposure head, etc.] Figure 2 is a schematic diagram showing the arrangement of the exposure head 22 and other components. Figure 2 schematically shows the arrangement of the exposure head 22, AF sensor 28, and AF assist sensor 29 when viewed from the positive side in the Z direction. It also shows the moving stage 19 being transported from the negative side in the Y direction.

[0043] The eight exposure heads 22 include two exposure head rows 22a and 22b, which are rows arranged along the X direction. Exposure head rows 22a and 22b are rows in which four exposure heads 22 are arranged adjacent to each other without gaps in the X direction. Exposure head row 22b is located on the negative side in the Y direction compared to exposure head row 22a. The exposure head array 22a corresponds to one embodiment of the first exposure head array according to this technology. The exposure head row 22b corresponds to one embodiment of the second exposure head row according to this technology.

[0044] Furthermore, the exposure head rows 22a and 22b are positioned offset in the X direction. In this example, the exposure head rows 22a and 22b are offset by half a pitch (the radius of the exposure head 22) and are arranged in a staggered pattern.

[0045] The eight AF sensors 28 are arranged in a line along the X direction between the exposure head rows 22a and 22b. Each AF sensor 28 is provided in conjunction with each exposure head 22. Specifically, one AF sensor 28 is provided in conjunction with each exposure head 22 such that their centers coincide in the X direction. As a result, the number of exposure heads 22 and the number of AF sensors 28 are both eight.

[0046] In this example, the number of AF assist sensors 29 is less than the number of AF sensors 28. Specifically, only one AF assist sensor 29 is provided. That is, the AF assist sensor 29 is located between the exposure head rows 22a and 22b, at the same position as the center of the eight AF sensors 28 in the X direction.

[0047] Furthermore, within the scope of what is feasible with this technology, the specific arrangement of the exposure head 22, AF sensor 28, and AF assist sensor 29 is not limited. For example, the offset between exposure head rows 22a and 22b is not limited to half a pitch, but may be any distance less than the spacing between the exposure heads 22 in the X direction. Also, there may be only one row of exposure heads, or there may be three or more rows. The exposure heads 22 may be arranged with gaps in the X direction.

[0048] The AF sensor 28 and the AF assist sensor 29 do not have to be positioned between the exposure head rows 22a and 22b. The AF sensor 28 does not have to be positioned so that its center coincides with that of the exposure head 22. The phrase "the AF sensor 28 is provided in correspondence with the exposure head 22" includes cases such as one AF sensor 28 being positioned in correspondence with two exposure heads 22.

[0049] Furthermore, the number of AF sensors 28 does not have to be the same as the number of exposure heads 22. For example, if AF sensors 28 are provided in a 2:1 ratio as described above, the number of AF sensors 28 will be 4, which is less than the number of exposure heads 22. Similarly, the number of AF assist sensors 29 can be arbitrary, and their positions are not limited. For example, three AF ​​assist sensors 29 may be arranged in positions that divide the exposure surface 14a into three parts in the X direction.

[0050] [Measurement range] Figure 3 is a schematic diagram showing the measurement range, etc. The shaded area in Figure 3 represents the tracking range of the prism pair 49, the measurement range of the AF sensor 28, and the measurement range of the AF assist sensor 29. The tracking range of the prism pair 49 is the range from -d1 to +d1 with a predetermined position as the origin. The tracking range refers to the range of exposure distances in which the focal position can be adjusted solely by moving the prism pair 49.

[0051] In other words, when the exposure distance is within the range of -d1 to +d1, focusing can be adjusted solely by moving the prism pair 49. On the other hand, when the exposure distance is outside the range of -d1 to +d1, focusing cannot be adjusted solely by moving the prism pair 49. In this case, control is required, for example, by moving the moving stage 19 in the Z direction to change the exposure distance.

[0052] The AF sensor 28 has a predetermined first measurement range. That is, if the exposure distance is within the range of the first measurement range, the AF sensor 28 correctly outputs the exposure distance as a measured value, but if the exposure distance is outside the range of the first measurement range, it outputs a value different from the exposure distance as a measured value.

[0053] In this example, the first measurement range is -d2 to +d2. Therefore, the first measurement range is wider than the tracking range of prism pair 49. Specifically, the tracking range of prism pair 49, -d1 to +d1, is included in the first measurement range, -d2 to +d2. In other words, d2 is greater than d1.

[0054] For example, if the exposure distance is d2+h (outside the first measurement range), the measured value d2-h may be output. In other words, a specific value is output instead of an error value. Therefore, when a measured value of d2-h is output, it may be impossible to determine whether the exposure distance is actually d2-h or d2+h.

[0055] The AF auxiliary sensor 29 has a predetermined second measurement range. In this example, the second measurement range is in the range of -d3 to +d3. Therefore, the second measurement range is wider than the first measurement range.

[0056] In this example, the sensing accuracy of the AF sensor 28 is higher than that of the AF assist sensor 29. That is, for example, even when the exposure distance is within the measurement range, there will be some error in the measurements of both the AF sensor 28 and the AF assist sensor 29, but the error from the AF sensor 28 tends to be smaller than the error from the AF assist sensor 29. The specific degree of the difference in sensing accuracy is not limited. Also, the specific ranges of the tracking range, the first measurement range, and the second measurement range are not limited.

[0057] [Function Block] Figure 4 is a schematic diagram showing an example of the configuration of the control device 13. The control device 13 is implemented by any computer, such as a PC (Personal Computer). The control device 13 includes a display unit 30, an operation unit 31, a communication unit 32, a storage unit 33, and a controller 34. These blocks are interconnected via a bus 35. Instead of the bus 35, each block may be connected using a communication network or a non-standardized proprietary communication method.

[0058] The display unit 30 is a display device that uses, for example, liquid crystal or electroluminescence (EL), and displays various images showing the status of the direct-writing exposure apparatus 2, a GUI (Graphical User Interface) for settings, etc.

[0059] The operating unit 31 may be, for example, a keyboard, a pointing device, a touch panel, or other operating device. If the operating unit 31 includes a touch panel, the touch panel may be integrated with the display unit 30.

[0060] The communication unit 32 is a communication module for communicating with other devices via a network such as a LAN (Local Area Network) or WAN (Wide Area Network). It may be equipped with a wireless LAN module such as WiFi, or a communication module for short-range wireless communication such as Bluetooth®. Communication equipment such as a modem or router may also be used.

[0061] The storage unit 33 is a storage device such as non-volatile memory, for example, an HDD (Hard Disk Drive) or SSD (Solid State Drive). Any other non-transient storage medium readable by a computer may be used. The storage unit 33 stores a control program for controlling the overall operation of the control device 13. The method of installing the control program to the control device 13 is not limited. For example, installation may be performed via various recording media, or the program may be installed via the internet, etc. The storage unit 33 also stores drawing patterns related to exposure.

[0062] In addition, the control device 13 may be equipped with a speaker or the like, and the current status of the direct-writing exposure apparatus 2 may be output by voice.

[0063] The controller 34 controls the operation of each block in the control device 13. The controller 34 has hardware circuits necessary for a computer, such as a CPU and memory (RAM, ROM). Various processes are executed by the CPU executing the program related to this technology stored in the storage unit 33 and memory. As the controller 34, devices such as FPGAs (Field Programmable Gate Arrays) or other PLDs (Programmable Logic Devices) or ASICs (Application Specific Integrated Circuits) may be used.

[0064] In this embodiment, the CPU of the controller 34 executes a program related to this technology (for example, an application program), thereby realizing the following functional blocks: a position acquisition unit 36, a sensor control unit 37, a measurement value acquisition unit 38, a determination unit 39, a movement amount calculation unit 40, a stage control unit 41, a prism pair control unit 42, and an irradiation control unit 43. These functional blocks then execute the exposure method according to this embodiment. Dedicated hardware such as ICs (integrated circuits) may be used as appropriate to realize each functional block.

[0065] The position acquisition unit 36 ​​acquires the position of the moving stage 19. Specifically, it acquires the position of the moving stage 19 in the Y direction from the measuring instrument 26 via the communication unit 32. Alternatively, the control device 13 and the measuring instrument 26 may be connected by a cable or the like, and the position may be acquired via wired communication. When the control device 13 communicates with other mechanisms, wired communication via the communication unit 32 or wireless communication via a cable or the like is performed.

[0066] The position acquisition unit 36 ​​also acquires the position of the moving stage 19 in the Z direction from another measuring instrument, for example, not shown in Figure 1. In addition, if the moving stage 19 can move or rotate in the X direction, the position or rotation angle in the X direction may also be acquired.

[0067] Next, the position acquisition unit 36 ​​acquires the position of the exposure surface 14a. Specifically, an image is acquired from the camera 27, and the position of the exposure surface 14a on the moving stage 19 is calculated based on the alignment marks 15 included in the image. Furthermore, the position acquisition unit 36 ​​calculates the Y-direction and Z-direction positions of the exposure surface 14a based on the position of the exposure surface 14a on the moving stage 19, the Y-direction position of the moving stage 19, and the Z-direction position of the moving stage 19.

[0068] The sensor control unit 37 controls the driving of the AF sensor 28 and the AF assist sensor 29. The measurement value acquisition unit 38 simultaneously acquires the Y-direction position of the exposure surface 14a from the position acquisition unit 36 ​​and the measurement values ​​from the AF sensor 28 and the AF assist sensor 29, thereby acquiring measurement values ​​linked to the Y-direction position.

[0069] The determination unit 39 determines whether the exposure distance exceeds the first measurement range based on the measurement values ​​of the AF sensor 28 and the AF assist sensor 29. Specifically, the determination unit 39 determines that the exposure distance exceeds the first measurement range if there is a certain degree of difference between the two measurement values.

[0070] In Figure 3, for example, in the example mentioned above, when the measurement value of the AF sensor 28 is d2-h, there are two possibilities: (1) the actual exposure distance is also d2-h, and (2) the exposure distance is d2+h. On the other hand, the second measurement range of the AF assist sensor 29 is -d3 to +d3, so the measurement value is d2-h in case (1) and d2+h in case (2). Therefore, in case (1), the two measurement values ​​will match, and in case (2), the two measurement values ​​will differ significantly. Note that since there are errors in both sensors, even in case (1), the two measurement values ​​will not match exactly, but in any case, there will be no major difference.

[0071] Therefore, for example, by setting a predetermined threshold and detecting whether or not there is a difference of more than the threshold between two measured values, it is possible to determine whether or not the exposure distance exceeds the first measurement range.

[0072] Furthermore, if the determination unit 39 determines that the exposure distance is within the first measurement range (i.e., not exceeding it), it determines, based on the measurement value of the AF sensor 28, whether or not the exposure distance exceeds the tracking range of the prism pair 49. That is, if the measurement value of the AF sensor 28 is within the range of -d1 to +d1, it is determined that the exposure distance does not exceed the tracking range, and in all other cases, it is determined that the exposure distance exceeds the tracking range.

[0073] The movement amount calculation unit 40 calculates the amount of movement of the moving stage 19 in the Z direction. The movement amount calculation unit 40 also calculates the amount of movement of the prism pair 49 in the Y direction during exposure. The specific details of these calculations will be described later.

[0074] The stage control unit 41 moves the moving stage 19 in the Z direction by controlling the movement mechanism based on the amount of movement of the moving stage 19 in the Z direction calculated by the movement amount calculation unit 40. The stage control unit 41 also moves the moving stage 19 in the Y direction during exposure.

[0075] The prism pair control unit 42 moves the prism pair 49 in the Y direction during exposure by controlling the drive mechanism based on the amount of movement of the prism pair 49 in the Y direction calculated by the movement amount calculation unit 40.

[0076] The irradiation control unit 43 reads the drawing pattern stored in the memory unit 33 and controls the operation of the light source unit 11, the image processing unit 12, and their respective exposure heads 22 to control the irradiation of exposure light onto the exposure surface 14a.

[0077] Furthermore, the specific configurations of each mechanism of the control device 13 and each functional block of the controller 34 are not limited.

[0078] Figure 5 is a flowchart showing an example of the exposure process. During this process, the position acquisition unit 36 ​​continuously acquires the Y and Z positions of the exposure surface 14a, and outputs them to the measurement value acquisition unit 38, etc., as shown in Figure 4.

[0079] First, the exposure distance is sensed (step 101). Specifically, the movement of the moving stage 19 is controlled by the stage control unit 41, so that the moving stage 19 moves from the initial position shown in Figure 1 to the positive side in the Y direction. When the moving stage 19 approaches directly below the AF sensor 28 and the AF assist sensor 29, the sensor control unit 37 starts driving these sensors, and the exposure distance between each exposure head 22 and each position on the exposure surface 14a is sensed.

[0080] For example, the leftmost exposure head 22 and the leftmost AF sensor 28 shown in Figure 2 are at the same position in the X direction. Therefore, by driving the AF sensor 28, the exposure distance between the exposure head 22 and the exposure surface 14a at that position in the X direction is sensed by scanning toward the Y direction. As a result, the measurement value acquisition unit 38 acquires multiple measurement values ​​that link the position in the Y direction with the exposure distance. The sensing is performed at a predetermined measurement pitch, such as 1 mm intervals, in the Y direction.

[0081] Similarly, sensing is performed on the other exposure heads 22 by the corresponding AF sensors 28. The measurement value acquisition unit 38 then acquires multiple measurement values, each linked to the position in the Y direction and the exposure distance at the position in the X direction. In this way, the measurement value acquisition unit 38 acquires the exposure distance between each position of the exposure head 22 and the exposure surface 14a.

[0082] Furthermore, the AF assist sensor 29 performs sensing only at the position in the X direction of the AF assist sensor 29. The measurement value acquisition unit 38 then acquires multiple measurement values, linked to the Y direction position and exposure distance, only at the position in the X direction. After these sensing operations are completed, the moving stage 19 waits at the terminal position (the upper right end position in Figure 1).

[0083] The determination unit 39 determines whether the exposure distance exceeds the first measurement range (step 102). First, the determination unit 39 obtains the measured values ​​of the AF sensor 28 and the AF assist sensor 29 from the measured value acquisition unit 38.

[0084] For example, the determination unit 39 calculates the difference between the measurement value of the AF sensor 28 at each position on the exposure surface 14a and the measurement value of the AF assist sensor 29 at the Y-direction position of that position. If any one of the multiple differences exceeds a threshold, it is determined that the exposure distance exceeds the first measurement range. On the other hand, if all of the multiple differences are below the threshold, it is determined that the exposure distance does not exceed the first measurement range.

[0085] It should be noted that this method of determination is merely one example, and there are no specific methods for determining whether the exposure distance exceeds the first measurement range. For example, a determination may be made that allows cases where some of the differences exceed a threshold. This is also true for the determination in step 103, which will be described later.

[0086] If the exposure distance does not exceed the first measurement range (No. in step 102), the determination unit 39 determines whether the exposure distance exceeds the tracking range of the prism pair 49 (step 103). Specifically, if even one of the measurements of the AF sensor 28 at each position on the exposure surface 14a exceeds the tracking range, it is determined that the exposure distance exceeds the tracking range. On the other hand, if all measurements are within the tracking range, it is determined that the exposure distance does not exceed the tracking range.

[0087] If the exposure distance does not exceed the tracking range (No. in step 103), the exposure process is performed (step 104). First, the movement amount calculation unit 40 calculates the amount of movement of the prism pair 49 during exposure based on the exposure distance. The exposure distance is within the tracking range at any position on the exposure surface 14a. Therefore, at each position on the exposure surface 14a, there is an amount of movement of the prism pair 49 such that the focal position of the exposure light is appropriate, and the movement amount calculation unit 40 calculates this appropriate amount of movement.

[0088] Next, the moving stage 19 is moved to the negative side in the Y direction under the control of the stage control unit 41. From the moment the exposure surface 14a is directly below the exposure head 22, the movement of the prism pair 49 is controlled by the prism pair control unit 42 based on the amount of movement. At the same time, the irradiation control unit 43 controls the irradiation of exposure light onto the exposure surface 14a by each of the multiple exposure heads 22. This performs exposure on the exposure surface 14a. In this example, since the exposure heads 22 are arranged in a staggered pattern, it is possible to perform exposure in one go, but exposure may be performed in two or more stages.

[0089] On the other hand, if the exposure distance exceeds the tracking range (Yes in step 103), the movement stage 19 is moved in the Z direction based on the measurement value of the AF sensor 28 so that the exposure distance falls within the tracking range (step 105). First, the movement amount calculation unit 40 calculates the amount of movement of the movement stage 19. Specifically, for example, the maximum and minimum values ​​are detected from all the measurement values ​​from all the AF sensors 28, and the inverse of their average value (multiplied by minus 1) is calculated as the amount of movement.

[0090] For example, consider the case where the center of the tracking range or measurement range is the origin, as in Figure 3, and the maximum value of the measured value is +300 and the minimum value is -250. In this case, the average of the maximum and minimum values ​​is +50, so the inverse of that, -50, is the amount of movement.

[0091] This process can also be described as calculating the average of the maximum and minimum exposure distances within the plane of the exposure surface 14a. Alternatively, the average value or the inverse of the median of all exposure distances within the plane may be calculated as the amount of movement, and the specific calculation method is not limited.

[0092] Next, the stage control unit 41 adjusts the position of the moving stage 19 in the Z direction based on the calculated amount of movement. After that, exposure processing is performed (step 104).

[0093] If it is determined in step 102 that the exposure distance exceeds the first measurement range (No. in step 102), it is determined whether or not resensing, described later, has already been performed (step 106). If resensing has not yet been performed (No. in step 106), the moving stage 19 is moved in the Z direction based on the measurement value of the AF assist sensor 29 so that the exposure distance falls within the first measurement range (step 107).

[0094] First, the movement amount calculation unit 40 calculates the movement amount of the movement stage 19. Specifically, for example, the maximum and minimum values ​​of all measurements from the AF assist sensor 29 are detected, and the inverse of their average value is calculated as the movement amount.

[0095] This process can also be described as calculating the average of the maximum and minimum exposure distances on the line where the AF assist sensor 29 is located on the exposure surface 14a. Furthermore, the specific method for calculating the amount of movement is not limited.

[0096] Next, the stage control unit 41 adjusts the position of the moving stage 19 in the Z direction based on the calculated amount of movement. After that, sensing (re-sensing) is performed again in the same way as in step 101 (step 108).

[0097] If it is determined in step 106 that resensing has been completed, that is, if the process in step 101 has been performed two or more times (Yes in step 106), the substrate 14 is ejected as defective (step 108), and the process ends without exposure to the exposure surface 14a.

[0098] Furthermore, sensing may be performed three or more times. However, after the position adjustment of the moving stage 19 in step 107, it is generally determined in step 102 that the exposure distance does not exceed the first measurement range (No. in step 102).

[0099] In the direct-drawing exposure apparatus 2 according to this embodiment, the exposure distance, which is the distance between the multiple exposure heads 22 and the exposure surface 14a, is measured by an AF sensor 28 having a first measurement range wider than the tracking range of the prism pair 49, and an AF auxiliary sensor 29 having a second measurement range wider than the first measurement range. Furthermore, it is determined whether or not the exposure distance exceeds the first measurement range based on the measurements from the AF sensor 28 and the AF auxiliary sensor 29. This enables high-quality exposure processing.

[0100] Recent advancements in high-resolution exposure technology have necessitated the use of high-precision sensors for measuring exposed surfaces. However, high-precision sensors tend to have narrow measurement ranges, leading to a high frequency of range deviations due to substrate thickness errors. Furthermore, because high-precision sensors use laser interferometry, they output a measurement value even when the range is off, making it difficult to determine whether the measurement is correct or not.

[0101] In this technology, a wide-range AF assist sensor 29 is provided in addition to the high-precision AF sensor 28. Based on the measurements from these sensors, it is determined whether or not the exposure distance exceeds the first measurement range of the AF sensor 28. The measurements from the AF sensor 28 are then used in the final exposure stage, for example, to calculate the amount of movement of the prism pair 49.

[0102] This effectively complements the measurement range of the AF sensor 28, enabling accurate detection of range deviations and high-precision exposure. Furthermore, it prevents productivity losses due to range deviations.

[0103] Furthermore, this technology includes multiple exposure head rows 22a and 22b arranged in multiple rows along the X direction. This makes it possible to reduce the width of the direct-writing exposure apparatus 2 in the X direction. In particular, in this embodiment, since the exposure head rows 22a and 22b are arranged in two rows, it is possible to easily remove the exposure heads 22. That is, if they are arranged in three or more rows, the inner exposure heads 22 cannot be removed until the outer exposure heads 22 have been removed, but this does not occur when they are arranged in two rows.

[0104] Furthermore, in this technology, exposure head rows 22a and 22b are arranged offset in the X direction. As a result, areas not exposed by exposure head row 22a are exposed by exposure head row 22b, making it possible to expose the exposure surface 14a without any gaps.

[0105] Furthermore, in this technology, the AF sensor 28 and the AF assist sensor 29 are positioned between the exposure head rows 22a and 22b. This makes it possible to shorten the Y-direction stroke of the moving stage 19 during exposure. Also, because the two sensors and the exposure head 22 are positioned close together, sensing accuracy is improved.

[0106] Furthermore, in this technology, a prism pair 49 is provided for each of the multiple exposure heads 22. This makes it possible to perform high-precision exposure.

[0107] Furthermore, in this technology, the AF sensor 28 is arranged along the X direction. This makes it possible to reduce the width of the direct-draw exposure device 2 in the Y direction. It also enables high-precision sensing.

[0108] Furthermore, in this technology, the AF sensor 28 is provided in accordance with multiple exposure heads 22. This makes it possible to perform high-precision sensing.

[0109] Furthermore, in this technology, the number of AF sensors 28 may be less than the number of exposure heads 22. This makes it possible to reduce the cost associated with arranging the AF sensors 28. In addition, the power consumption associated with driving the AF sensors 28 is reduced.

[0110] Furthermore, in this technology, the number of AF assist sensors 29 is less than the number of AF sensors 28. In cases where the substrate 14 is held by suction on the moving stage 19, as in this example, the irregularities within the substrate 14 are often small. Therefore, it may be sufficient to place only one AF assist sensor 29 and sense only the central line of the substrate. By reducing the number of AF assist sensors 29, it is possible to reduce the cost associated with placement. In addition, the power consumption related to driving the AF assist sensors 29 is reduced.

[0111] Furthermore, in this technology, multiple exposure heads 22, AF sensors 28, and AF assist sensors 29 are supported by a common support (the housing portion of the exposure unit 20 and the first gate 21). This makes it possible to make the degree of positional change of the multiple exposure heads 22, AF sensors 28, and AF assist sensors 29 the same when the support expands due to heat, thereby reducing sensing errors.

[0112] Furthermore, in this technology, if it is determined that the exposure distance exceeds the first measurement range, the moving stage 19 is moved in the Z direction based on the measurement value of the AF assist sensor 29 so that the exposure distance falls within the first measurement range. This ensures that the exposure distance is reliably brought within the first measurement range.

[0113] Furthermore, in this technology, when it is determined that the exposure distance is within the first measurement range, it is determined whether or not the exposure distance exceeds the tracking range based on the measurement value of the AF sensor 28. If it is determined that the exposure distance exceeds the tracking range, the moving stage 19 is moved in the Z direction based on the measurement value of the AF sensor 28 so that the exposure distance falls within the tracking range. This ensures that the exposure distance is reliably brought within the tracking range.

[0114] Furthermore, in this technology, after the movement of the moving stage 19 is completed so that the exposure distance falls within the tracking range, the moving stage 19 is moved in the Y direction while exposure light is irradiated onto the exposure surface 14a by each of the multiple exposure heads 22. This makes it possible to reliably adjust the focus of the exposure light by the prism pair 49.

[0115] <Other Embodiments> This technology is not limited to the embodiments described above, and various other embodiments can be realized.

[0116] If feasible, the AF sensor 28 and AF assist sensor 29 may be distance measuring sensors such as LiDAR (light detection and ranging). Furthermore, the specific types of AF sensor 28 and AF assist sensor 29 are not limited.

[0117] If this technology is feasible, the prism pair 49 may be provided only on some of the exposure heads 22.

[0118] If it is determined during sensing that the exposure distance exceeds the first measurement range, sensing may be immediately interrupted and the position of the moving stage 19 may be adjusted.

[0119] It is also possible to combine at least two of the feature features of the present technology described above. In other words, the various feature features described in each embodiment may be combined arbitrarily, regardless of the specific embodiment. Furthermore, the various effects described above are merely examples and not limiting, and other effects may also be exhibited. [Explanation of Symbols]

[0120] 2…Direct-writing exposure system 10…Direct-drawing exposure machine 13…Control device 14… Circuit board 14a... Exposure surface 19…Moving Stage 20... Exposure area 21…First Gate 22… Exposure head 22a, 22b... Exposure head rows 28…AF sensor 29…AF assist sensor 34…Controller 36...Position acquisition section 37...Sensor control unit 38...Measurement value acquisition unit 39...Judgment section 40...Movement amount calculation unit 41…Stage Control Unit 42...Prism Pair Control Unit 43... Irradiation control unit 49...Prism Pair

Claims

1. A direct-drawing exposure apparatus that irradiates exposure light onto the irradiation surface of a substrate while transporting the substrate in a first direction parallel to the irradiation surface of the substrate, A stage on which the aforementioned substrate is placed, A plurality of exposure heads, each irradiating the irradiation surface with the exposure light, A moving mechanism moves the stage relative to the plurality of exposure heads in a first direction and a second direction perpendicular to the irradiation surface, An autofocus module provided in at least one of the plurality of exposure heads, which adjusts the focal position of the exposure light in the second direction and has a tracking range that is a range in which the focal position can be adjusted, The distance between the plurality of exposure heads and the irradiation surface in the second direction is measured, and a first distance meter having a first measurement range wider than the tracking range is used. The distance between the plurality of exposure heads and the irradiation surface in the second direction is measured, and a second distance meter having a second measurement range wider than the first measurement range is used. A controller that determines whether the distance between the plurality of exposure heads and the irradiation surface exceeds the first measurement range, based on the distance measured by the first rangefinder and the distance measured by the second rangefinder. A direct-writing exposure apparatus equipped with the following:

2. A direct-writing exposure apparatus according to claim 1, The plurality of exposure heads include a first row of exposure heads and a second row of exposure heads arranged in multiple rows parallel to the irradiation surface and along a third direction intersecting the first direction. Direct-writing exposure system.

3. A direct-writing exposure apparatus according to claim 2, The first and second exposure head rows are arranged to be offset in the third direction. Direct-writing exposure system.

4. A direct-writing exposure apparatus according to claim 2 or 3, The first and second rangefinders are positioned between the first and second exposure head rows. Direct-writing exposure system.

5. A direct-writing exposure apparatus according to claim 1 or 2, The autofocus module is provided in each of the plurality of exposure heads. Direct-writing exposure system.

6. A direct-writing exposure apparatus according to claim 1 or 2, The number of the first rangefinders is two or more. Each of the first rangefinders is positioned along a third direction that is parallel to the illumination surface and intersects the first direction. Direct-writing exposure system.

7. A direct-writing exposure apparatus according to claim 1 or 2, The first rangefinder is provided in accordance with the plurality of exposure heads. Direct-writing exposure system.

8. A direct-writing exposure apparatus according to claim 1 or 2, The number of the first rangefinders is less than the number of the multiple exposure heads. Direct-writing exposure system.

9. A direct-writing exposure apparatus according to claim 1 or 2, The number of the second rangefinders is less than the number of the first rangefinders. Direct-writing exposure system.

10. A direct-writing exposure apparatus according to claim 1 or 2, The plurality of exposure heads, the first rangefinder, and the second rangefinder are supported by a common support. Direct-writing exposure system.

11. A direct-writing exposure apparatus according to claim 1 or 2, If the controller determines that the distance between the plurality of exposure heads and the illumination surface exceeds the first measurement range, it moves the stage in the second direction based on the distance measured by the second distance meter so that the distance between the plurality of exposure heads and the illumination surface falls within the first measurement range. Direct-writing exposure system.

12. A direct-writing exposure apparatus according to claim 1 or 2, When the controller determines that the distance between the plurality of exposure heads and the illumination surface is within the first measurement range, it determines, based on the distance measured by the first distance meter, whether the distance between the plurality of exposure heads and the illumination surface exceeds the tracking range. If it determines that the distance exceeds the tracking range, it moves the stage in the second direction, based on the distance measured by the first distance meter, so that the distance between the plurality of exposure heads and the illumination surface falls within the tracking range. Direct-writing exposure system.

13. An exposure method comprising irradiating the irradiation surface with exposure light while transporting the substrate in a first direction parallel to the irradiation surface of the substrate, The aforementioned substrate is placed on the stage, The focal position of the exposure light is adjusted in a second direction perpendicular to the irradiation surface, and the exposure light is irradiated onto the irradiation surface by each of a plurality of exposure heads, each of which is provided with at least one autofocus module having a tracking range that is a range in which the focal position can be adjusted. The stage is moved in the first direction and the second direction relative to the plurality of exposure heads. A first distance meter having a first measurement range wider than the aforementioned tracking range measures the distance between the plurality of exposure heads and the irradiation surface in the second direction. A second distance meter having a second measurement range wider than the first measurement range measures the distance between the plurality of exposure heads and the irradiation surface in the second direction. Based on the distance measured by the first rangefinder and the distance measured by the second rangefinder, it is determined whether the distance between the plurality of exposure heads and the illumination surface exceeds the first measurement range. Exposure method.

14. The exposure method according to claim 13, If it is determined that the distance between the plurality of exposure heads and the illumination surface exceeds the first measurement range, the stage is moved in the second direction based on the distance measured by the second distance meter so that the distance between the plurality of exposure heads and the illumination surface falls within the first measurement range. After the movement in the second direction is completed, the stage is moved in the first direction while the exposure light is irradiated onto the irradiation surface by each of the plurality of exposure heads. Exposure method.

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