KR20200033723A - Drawing apparatus and drawing method - Google Patents

Abstract

A drawing head (31) of a drawing device has a light source (32), a light modulation device (341), and a projection optical system (35). Light from the light source (32) is introduced to the light modulation device (341). The projection optical system (35) induces light modulated by the light modulation device (341) to a stage (21). The projection optical system (35) includes an objective lens group (352), a focus lens group (351), and a focus adjustment mechanism (353). The focus adjustment mechanism (353) adjusts the focus position of the drawing head (31) by changing a position on the optical axis of the focus lens group (351). A head control unit controls the focus adjustment mechanism (353) based on a pressure around the drawing head (31) measured by a pressure sensor. Accordingly, the offset of the focus position of the drawing head (31) resulting from pressure fluctuation around the drawing head (31) can be corrected.

Description

Drawing device and drawing method {DRAWING APPARATUS AND DRAWING METHOD}

The present invention relates to a technique for irradiating light onto a substrate to perform pattern drawing.

Conventionally, a direct drawing device is known in which a pattern is drawn by irradiating a modulated light onto an object on a stage and scanning the irradiation area of the light on the object (for example, JP 2014-197136 A (Document 1)). .

In the direct drawing device of document 1, when the crosslinking structure supporting the drawing head or the crosslinking structure supporting the alignment camera is deformed by the heat of the device itself, the drawing position on the substrate by the drawing head and the viewing position of the alignment camera The positional relationship is disturbed. Thus, by correcting the positional shift of the temperature dependence between the drawing position and the field of view based on the amount of positional shift corresponding to the temperature difference, a decrease in rendering accuracy is suppressed.

On the other hand, Japanese Patent Application Laid-Open No. 2013-210440 (Document 2) discloses a projection exposure apparatus that exposes a pattern formed on a mask by projecting it onto a workpiece with a projection lens. In the projection exposure apparatus, the imaging of the alignment mark formed on the mask is measured to measure the change in the position of the projection lens due to the difference in temperature, and the exposure is performed by reflecting the change in the patterning position of the exposure pattern.

In addition, Japanese Laid-Open Patent Publication No. 2002-195913 (Document 3) discloses an exposure apparatus that transfers an image of a circuit pattern onto a wafer by a step-and-repeat method using a reticle in which a circuit pattern of a semiconductor element is formed. It is done. In the exposure apparatus, changes in imaging characteristics of the projection optical system due to environmental changes such as temperature and air pressure are detected from changes in the position of the image when a specific pattern is irradiated on the projection surface, and imaging characteristics of the projection optical system are changed to optimize It is controlled by the state. The detection of an image position change is performed by analyzing an image acquired by a camera capable of observing the projection surface.

By the way, in an apparatus for directly drawing a circuit pattern on a printed board, in accordance with the miniaturization of the circuit pattern, high definition of drawing is required. For this reason, even a relatively small temperature fluctuation and a change in the focal length resulting from a pressure fluctuation in the clean room may have a significant influence on the imaging accuracy. In the device, a method is known in which an inner cover covering the barrel of the projection optical system is installed to block the space around the barrel from the outside, and to reduce the temperature fluctuation by a temperature controller, but maintaining the temperature of the entire projection optical system in a uniform state It is not easy. In addition, the method cannot reduce the change in the focal length resulting from pressure fluctuation.

The present invention relates to a drawing device that irradiates light onto a substrate to draw a pattern, and aims to correct a shift in focus position due to pressure fluctuation.

A drawing apparatus according to a preferred embodiment of the present invention includes a stage for holding a substrate, a drawing head for irradiating modulated light to the substrate, and the stage in a direction parallel to the upper surface of the substrate, relative to the drawing head. It includes a stage movement mechanism for relatively moving, a pressure sensor for measuring the pressure around the drawing head, and a head control unit for controlling the drawing head. The drawing head includes a light source, a light modulation device through which light from the light source is derived, and a projection optical system that guides light modulated by the light modulation device to the stage. The projection optical system includes an objective lens group, a focus lens group, and a focus adjustment mechanism that adjusts the focus position of the drawing head by changing the position on the optical axis of the focus lens group. The head control unit controls the focus adjustment mechanism based on the output from the pressure sensor. ADVANTAGE OF THE INVENTION According to this invention, the shift | offset | difference of the focus position by pressure fluctuation can be corrected.

Preferably, the drawing head further includes a first temperature sensor that measures the temperature of the projection optical system. Control of the focus adjustment mechanism by the head control unit is also performed based on the output from the first temperature sensor.

Preferably, the drawing head further includes a distance sensor that measures a distance to the substrate on the stage. While the imaging is performed on the substrate by moving the stage relative to the stage by the stage moving mechanism and scanning the irradiation area of the light from the drawing head on the substrate, the distance sensor measures the distance to the substrate. It is carried out continuously. Control of the focus adjustment mechanism by the head control unit is also performed based on the output from the distance sensor. While the drawing of the substrate is being performed, the focus position of the drawing head is adjusted to the upper surface of the substrate by the control of the focus adjusting mechanism by the head control unit.

Preferably, the drawing head further includes a second temperature sensor that measures the temperature of the distance sensor. Control of the focus adjustment mechanism by the head control unit is also performed based on the output from the second temperature sensor.

Preferably, the drawing device includes: a jig fixed to the stage, and an imaging unit that captures an area of irradiation of light from the drawing head on the jig together with a mark formed in advance on the jig, On the basis of the image acquired by the imaging unit, an image processing unit that acquires a deviation from the design irradiation position of the irradiation position of the drawing head is further provided. When imaging of the jig by the imaging unit is performed, the focus position of the drawing head is adjusted to the jig by control of the focus adjustment mechanism by the head control unit.

Preferably, imaging of the substrate is completed by moving the stage relative to the stage by the stage moving mechanism to scan the light irradiation area from the drawing head only once in a predetermined scanning direction on the substrate.

Preferably, the pattern drawn on the substrate is a circuit pattern. The L / S line of the circuit pattern is 7 µm to 9 µm, and the space is 11 µm to 13 µm.

Preferably, the focus lens group is moved independently from the objective lens group by the focus adjustment mechanism.

The present invention provides a stage for holding a substrate, a drawing head for irradiating modulated light to the substrate, and a stage moving mechanism for moving the stage relative to the drawing head in a direction parallel to the upper surface of the substrate. It also relates to a drawing method in which a pattern is drawn by irradiating light to a substrate by a drawing device provided. The drawing head includes a light source, a light modulation device through which light from the light source is derived, and a projection optical system that guides light modulated by the light modulation device to the stage. The projection optical system includes an objective lens group and a focus lens group. The drawing method comprises: a) measuring the pressure around the drawing head, and b) changing the position on the optical axis of the focus lens group based on the pressure measured in the step a). And a process of adjusting the focus position of the head. ADVANTAGE OF THE INVENTION According to this invention, the shift | offset | difference of the focus position by pressure fluctuation can be corrected.

Preferably, the drawing method further comprises a step of c) measuring the temperature of the projection optical system. The adjustment of the focal position of the drawing head in the step b) is performed based on the temperature measured in the step c).

Preferably, in the drawing method, d) in the step b), after the focal position of the drawing head is aligned with the upper surface of the substrate, the stage is moved relative to the stage by the stage moving mechanism to move from the drawing head. A step of drawing on the substrate by scanning an irradiation region of light on the substrate, and e) a step of continuously measuring a distance from the drawing head to the substrate on the stage in parallel with the step d). , f) in parallel with the step d), by changing the position on the optical axis of the focus lens group based on the distance measured in the step e), the focus position of the drawing head is the upper surface of the substrate It is further provided with a process for continuously matching to.

Preferably, the drawing method further comprises a step of measuring the temperature of the distance sensor used for measuring the distance from the step e) to the substrate in step e). The adjustment of the focal position of the drawing head in step b) is performed based on the temperature measured in step g).

Preferably, the drawing device further includes a jig fixed to the stage, and an imaging unit for imaging the jig. In the drawing method, h) in the step b), after the focal position of the drawing head is aligned with the jig, an irradiation area of light from the drawing head on the jig is previously formed on the jig. A step of imaging together with the marker, and i) a step of acquiring a deviation from the design irradiation position of the irradiation position of the drawing head based on the image obtained in the step h) is further provided.

Preferably, imaging of the substrate is completed by moving the stage relative to the stage by the stage moving mechanism to scan the light irradiation area from the drawing head only once in a predetermined scanning direction on the substrate.

Preferably, the pattern drawn on the substrate is a circuit pattern, the L / S line of the circuit pattern is 7 µm to 9 µm, and the space is 11 µm to 13 µm.

Preferably, in the step b), the focus lens group moves independently from the objective lens group.

The above-mentioned objects and other objects, features, aspects, and advantages will be clarified by the detailed description of the present invention which will be given below with reference to the accompanying drawings.

1 is a perspective view showing a configuration of a drawing device according to an embodiment.
2 is a view showing a configuration of a computer provided in the control unit.
3 is a block diagram showing the function of the control unit.
4 is a side view showing the drawing head.
5 is a side view showing the vicinity of an end of the stage.
It is a figure which shows the flow of adjustment of an autofocus mechanism.
It is a figure which shows the flow of drawing to a board | substrate.
8 is a diagram showing a calibration pattern.
9 is a view showing the flow of the head calibration.

1 is a perspective view showing a configuration of a drawing device 1 according to an embodiment of the present invention. In Fig. 1, three directions orthogonal to each other are indicated by arrows in the X direction, the Y direction, and the Z direction (as in other drawings). In the example shown in FIG. 1, the X direction and the Y direction are horizontal directions, and the Z direction is a vertical direction.

The drawing device 1 is a direct drawing device (so-called drawing device) that performs pattern drawing by irradiating a space-modulated, substantially beam-shaped light onto a photosensitive material on the substrate 9 and scanning the irradiation area of the light on an object. . The substrate 9 is, for example, a flexible printed wiring board. In the substrate 9, a resist film formed of a photosensitive material is formed on the copper layer. In the drawing device 1, a circuit pattern is drawn on the resist film of the substrate 9. In the circuit pattern, for example, the line of L / S (that is, the pattern width) is 7 µm to 9 µm, and the space of L / S (that is, the gap width between patterns) is 11 µm to 13 µm.

The drawing device 1 is disposed in a clean room in which illustration is omitted. The interior space of the clean room is controlled by a temperature control facility so as to reach a predetermined temperature. The drawing device 1 includes a stage 21, a stage moving mechanism 22, a stage lifting mechanism 23, a drawing unit 3, a pressure sensor 41, and a control unit 6 . The stage 21, the stage moving mechanism 22, the stage lifting mechanism 23, and the drawing unit 3 are accommodated inside the housing, not shown. The pressure sensor 41 is mounted on the inner surface of the housing, for example, and measures the pressure (ie, air pressure) inside the housing. The control unit 6 controls the stage moving mechanism 22, the stage lifting mechanism 23, the drawing unit 3, and the like.

2 is a diagram showing a configuration of the computer 8 included in the control unit 6. The computer 8 is a normal computer provided with a processor 81, a memory 82, an input / output unit 83, and a bus 84. The bus 84 is a signal circuit that connects the processor 81, the memory 82, and the input / output unit 83. The memory 82 stores programs and various information. The processor 81 performs various processes (for example, numerical calculation or image processing) while using the memory 82 or the like, depending on a program or the like stored in the memory 82. The input / output unit 83 includes a keyboard 85 and a mouse 86 that receive input from an operator, and a display 87 that displays output from the processor 81 and the like. In addition, the input / output unit 83 includes a transmission unit 88 that transmits output from the processor 81 and the like, and a reception unit 89 that receives output from each sensor described later. Further, the control unit 6 may be a programmable logic controller (PLC) or a circuit board, or a combination of these and one or more computers.

3 is a block diagram showing the function of the control unit 6 realized by the computer 8. In FIG. 3, the configuration other than the control part 6 is also shown. The control unit 6 includes a storage unit 61, an image processing unit 62, a head control unit 63, and a movement control unit 64. The storage unit 61 is mainly realized by the memory 82, and various information such as measurement values sent from the pressure sensor 41, the first temperature sensor 36 and the second temperature sensor 37 (described later) Remember. The image processing unit 62 is mainly implemented by the processor 81, and acquires various information from an image sent from the imaging unit 51 to be described later. The head control part 63 is mainly implemented by the processor 81, and controls the drawing head 31 (to be described later) of the drawing part 3. The movement control unit 64 is mainly realized by the processor 81, and controls the stage movement mechanism 22 and the like for moving the stage 21.

As shown in FIG. 1, the stage 21 is a substantially flat plate-shaped holding portion that holds the substrate 9 in a horizontal state from the lower side of the drawing portion 3 (that is, the (-Z) side). . The surface of the substrate 9 held by the stage 21 on the (+ Z) side (hereinafter referred to as "top surface 91") is approximately perpendicular to the Z direction and approximately to the X direction and the Y direction. Parallel

The stage lifting mechanism 23 moves the stage 21 in the Z direction. The stage movement mechanism 22 moves the stage 21 relative to the drawing unit 3. In the example shown in FIG. 1, the stage movement mechanism 22 moves the stage 21 together with the stage elevation mechanism 23 in the X direction and the Y direction. In other words, the stage movement mechanism 22 moves the stage 21 relative to the drawing unit 3 in a direction substantially parallel to the upper surface 91 of the substrate 9.

The stage movement mechanism 22 is, for example, a mechanism for linearly moving the stage 21 along a guide rail, and, for example, a linear servomotor is used as a driving source. Thereby, the stage 21 moves with high precision. As a drive source of the stage moving mechanism 22, a ball screw may be used with a motor. In the drawing device 1, the stage lifting mechanism 23 may be omitted, or a rotating mechanism that rotates the stage 21 around an axis parallel to the Z direction may be formed.

The drawing unit 3 includes a plurality of drawing heads 31 arranged in the X direction and the Y direction (five in the example shown in FIG. 1). The plurality of drawing heads 31 are supported above the stage 21 by a head support portion 11 formed over the stage 21. The plurality of drawing heads 31 have almost the same structure.

In the drawing device 1, the stage moving mechanism 22 while irradiating light modulated (that is, spatially modulated) from the plurality of drawing heads 31 of the drawing unit 3 on the upper surface 91 of the substrate 9 ) To move the substrate 9 in the Y direction. Thereby, the irradiation region of the light from the plurality of drawing heads 31 is scanned in the Y direction on the substrate 9, and the circuit pattern is drawn to the substrate 9. In the following description, the Y direction is also referred to as a “scanning direction” and the X direction is also referred to as a “width direction”. The stage movement mechanism 22 is a scanning mechanism that moves the irradiation region of light from each drawing head 31 in the scanning direction on the substrate 9.

In the drawing device 1, drawing to the substrate 9 is performed by a so-called single pass (one pass) method. Specifically, the stage moving mechanism 22 moves the stage 21 relative to the plurality of drawing heads in the Y direction, and the irradiation region of the light from the plurality of drawing heads 31 is a substrate ( On the upper surface 91 of 9), scanning is performed only once in the Y direction (ie, scanning direction). Thereby, drawing to the substrate 9 is completed.

4 is a side view showing the configuration of one drawing head 31. The drawing head 31 includes a light source 32, an illumination optical system 33, a light modulation unit 34, a projection optical system 35, a first temperature sensor 36, and a second temperature sensor 37 ) And a distance sensor 38. The light source 32 is, for example, a light emitting diode (LED) light source or a laser diode (LD) light source. The optical modulation unit 34 includes an optical modulation device 341. The optical modulation device 341 is, for example, a DMD (Digital Micromirror Device) in which a plurality of micromirrors are arranged in two dimensions. The light source 32 and the illumination optical system 33 are fixed to the upper part of the frame 30.

The projection optical system 35 includes a focus lens group 351, an objective lens group 352, and a focus adjustment mechanism 353. In Fig. 4, illustration of the lenses included in the focus lens group 351 is omitted, and reference numeral 351 is attached to the barrel in which the lens is accommodated. The same is true for the objective lens group 352. The focus lens group 351 is attached to the upper portion of the frame 30 via a focus adjustment mechanism 353. The optical axis of the focus lens group 351 extends substantially parallel to the horizontal direction (eg, Y direction). The focus adjustment mechanism 353 moves the focus lens group 351 linearly in a direction parallel to the optical axis (for example, the Y direction). The focus adjustment mechanism 353 is a combination of, for example, a mechanism for driving a ball screw with a motor and a mechanism for guiding the focus lens group 351 in the Y direction. As the driving source of the focus adjustment mechanism 353, a linear servomotor may be used. The objective lens group 352 is fixed to the side of the frame 30. The optical axis of the objective lens group 352 extends substantially parallel to the Z direction (that is, the vertical direction). Movement of the focus lens group 351 by the focus adjustment mechanism 353 is performed independently from the objective lens group 352.

In the drawing device 1, the light emitted from the light source 32 of the drawing head 31 is guided to the light modulation unit 34 by the illumination optical system 33, and the light modulation device of the light modulation unit 34 After being spatially modulated at 341, it is guided to the substrate 9 on the stage 21 by the projection optical system 35 (ie, the focus lens group 351 and the objective lens group 352). In the projection optical system 35, the focus lens group 351 is moved by the focus adjustment mechanism 353, and the position of the focus lens group 351 on the optical axis of the drawing head 31 is changed, whereby the drawing head The focal position of 31 is adjusted in the vertical direction in the downward direction of the objective lens group 352.

The distance sensor 38 is attached to the objective lens group 352 of the projection optical system 35. Specifically, the distance sensor 38 is attached to the lower end of the barrel of the objective lens group 352. The distance sensor 38 measures the distance from the lower end of the objective lens group 352 to the substrate 9 on the stage 21 (hereinafter referred to as "irradiation distance"). The distance sensor 38 includes a light emitting portion 381, a light receiving portion 382, and a sensor frame 383. The sensor frame 383 is, for example, a substantially plate-shaped member extending in the Y direction, and is fixed to the lower end of the barrel of the objective lens group 352. The light emitting portion 381 is fixed to the end of the sensor frame 383 on the (-Y) side, and the light receiving portion 382 is fixed to the end of the sensor frame 383 on the (+ Y) side. The light emitted from the light emitting portion 381 to the (+ Y) side and to the (-Z) side is reflected by the upper surface 91 of the substrate 9 and is received by the light receiving portion 382. The light receiving portion 382 is, for example, a line sensor. And the irradiation distance mentioned above is calculated | required based on the light-receiving position in the light-receiving part 382 of the reflected light from the substrate 9.

In the drawing device 1, while the drawing on the substrate 9 is being performed, the above-mentioned irradiation distance is measured by the distance sensor 38 continuously. The irradiation distance (hereinafter referred to as "measurement irradiation distance") measured by the distance sensor 38 is output to the head control unit 63 (see Fig. 3) of the control unit 6. The head control unit 63 controls the focus adjustment mechanism 353 based on the output from the distance sensor 38. Thereby, the position of the focus lens group 351 is adjusted, and the focus position of the drawing head 31 is adjusted. In the drawing device 1, the focusing mechanism 353 is continuously controlled by the head control unit 63 while drawing is performed on the substrate 9, so that the focal position of the drawing head 31 is the substrate ( It fits on the upper surface 91 of 9). In other words, at the time of drawing in the drawing device 1, autofocusing is performed by the distance sensor 38, the focus adjustment mechanism 353, the head control unit 63, and the like. As a result, even if deformation such as warping occurs on the substrate 9, since the focal position of the drawing head 31 can be adjusted to the upper surface 91 of the substrate 9, high-precision drawing can be realized. . Details of the control of the focus adjustment mechanism 353 by the head control unit 63 will be described later.

The 1st temperature sensor 36 is attached to the projection optical system 35, or is arrange | positioned in the vicinity of the projection optical system 35, and measures the temperature of the projection optical system 35. In the example shown in FIG. 4, the first temperature sensor 36 is attached to the objective lens group 352 of the projection optical system 35. The first temperature sensor 36 is, for example, a thermocouple attached to the outer surface of the barrel of the objective lens group 352 at the lower end of the objective lens group 352. The temperature of the projection optical system 35 measured by the first temperature sensor 36 (hereinafter referred to as "measurement temperature of the projection optical system 35") is output to the head control unit 63 of the control unit 6. . The control of the focus adjustment mechanism 353 by the head control unit 63 is also performed based on the output from the first temperature sensor 36.

The second temperature sensor 37 is mounted on the distance sensor 38 or is disposed in the vicinity of the distance sensor 38 to measure the temperature of the distance sensor 38. In the example shown in FIG. 4, the second temperature sensor 37 is attached to the sensor frame 383 of the distance sensor 38. The second temperature sensor 37 is, for example, a thermocouple attached to the vicinity of the light receiving portion 382 of the sensor frame 383. The temperature of the distance sensor 38 measured by the second temperature sensor 37 (hereinafter referred to as "measurement temperature of the distance sensor 38") is output to the head control unit 63 of the control unit 6. . Control of the focus adjustment mechanism 353 by the head control unit 63 is also performed based on the output from the second temperature sensor 37.

As described above, the pressure sensor 41 measures the pressure (that is, air pressure) inside the housing of the drawing device 1. Since the pressure inside the housing hardly changes even if the position inside the housing is different, the pressure measured by the pressure sensor 41 (hereinafter referred to as "measurement pressure") is defined by each drawing head 31 ) It is almost the same as the surrounding pressure. In other words, in the drawing device 1, the pressure around each drawing head 31 is measured by the pressure sensor 41. The pressure measured by the pressure sensor 41 is output to the head control unit 63 of the control unit 6. Control of the focus adjustment mechanism 353 by the head control unit 63 is also performed based on the output from the pressure sensor 41. The pressure sensor 41 is, for example, a diaphragm gauge.

5 is a side view showing a configuration near the end of the stage 21 on the (+ Y) side. As shown in FIG. 5, the drawing device 1 further includes an imaging unit 51 and a jig 52. The jig 52 is a flat plate-like glass plate fixed to the side of the stage 21 on the (+ Y) side. The jig 52 protrudes in the (+ Y) direction from the side surface of the stage 21 so that the main surface is perpendicular to the Z direction. The upper surface of the jig 52 is located at the same position in the vertical direction as the upper surface 91 of the substrate 9 without deformation such as warping placed on the stage 21. The jig 52 is substantially rectangular, which is long in the X direction when viewed in a plane. The jig 52 is formed of a light-transmitting material, and is preferably transparent. On the upper surface of the jig 52, a number of marks arranged in the X direction are formed. The mark on the jig 52 is, for example, a cross pattern or another pattern.

The imaging unit 51 is mounted under the jig 52 via the imaging unit moving mechanism 53 on the side of the stage 21 on the (+ Y) side. The imaging unit 51 is, for example, a digital camera having a CCD (Charged Coupled Devices) or a CMOS (Complementary Metal Oxide Semiconductor) as an imaging element. The imaging unit 51 is movable in the X direction by the imaging unit moving mechanism 53. The imaging unit moving mechanism 53 is a combination of, for example, a mechanism for driving a ball screw with a motor and a mechanism for guiding the imaging unit 51 in the X direction. A linear servomotor may be used as a driving source of the imaging unit moving mechanism 53.

In the drawing device 1, the image pickup section 51 acquires an image from below the jig 52 in a state where light of a predetermined pattern is emitted from one drawing head 31 toward the jig 52. . The imaging part 51 captures the irradiation area of the light from the drawing head 31 on the jig 52 together with the above-mentioned marks previously formed on the jig 52. The image acquired by the imaging unit 51 is sent to the control unit 6, and the image is processed by the image processing unit 62 (see FIG. 3), whereby the drawing head 31 and the jig 52 are The positional relationship is obtained. As described above, since the jig 52 is fixed to the stage 21, the positional relationship between the drawing head 31 and the stage 21 is also obtained by the calculation processing.

Next, control of the focus adjustment mechanism 353 by the head control unit 63 will be described in detail with reference to FIGS. 6 and 7. In the drawing device 1, before the drawing on the substrate 9 is performed, adjustment of the autofocus mechanism (i.e., the distance sensor 38 and the focus adjustment mechanism 353) used for the autofocus described above is performed. Is implemented (see Figure 6). Then, drawing to the some board | substrate 9 is performed continuously. In FIG. 7, attention is paid to one substrate 9 and the flow of drawing to the substrate 9 is shown.

In the adjustment of the autofocus mechanism (so-called focus calibration), the focal position of each drawing head 31 is the same as the upper surface of the jig 52 in the vertical direction (i.e., the substrate 9 without deformation such as bending) The position of the focus lens group 351 is adjusted so as to be positioned on the image plane 91).

The adjustment of the autofocus mechanism is carried out when the drawing device 1 is installed in a clean room, but the temperature and pressure (i.e., air pressure) in the clean room at the time of installation and the drawing on the substrate 9 It may be different from the temperature and pressure in the clean room. When the temperature in the clean room is different, each configuration of the drawing head 31 expands or contracts, and there is a possibility that the focal position of the drawing head 31 is shifted in the vertical direction from the upper surface 91 of the substrate 9. . Moreover, there is a possibility that a shift may occur also in the measurement irradiation distance by the distance sensor 38. If the pressure in the clean room is different, there is a possibility that the focal position of the drawing head 31 is shifted in the vertical direction from the upper surface 91 of the substrate 9 due to changes in the density of the atmosphere and the like. For example, when the pressure increases, the focal position of the drawing head 31 is shifted downward.

6 is a view showing an example of the flow of adjustment of the autofocus mechanism. In FIG. 6, the flow of adjustment of the autofocus mechanism with respect to one drawing head 31 is shown. When the autofocus mechanism is adjusted, the stage 21 is moved in the Y direction by the stage movement mechanism 22 (see Fig. 1), so that the drawing head 31 is positioned above the jig 52 in advance. . Moreover, the imaging part 51 is moved in the X direction by the imaging part moving mechanism 53, and the imaging part 51 is located below the said drawing head 31 beforehand. In addition, in the drawing apparatus 1, the adjustment of the autofocus mechanism illustrated in FIG. 6 is sequentially performed on the plurality of drawing heads 31.

In the adjustment of the autofocus mechanism, first, the pressure around the drawing head 31 is measured by the pressure sensor 41 (see FIG. 1). The measurement pressure obtained by the pressure sensor 41 is sent to the control unit 6 and stored as a "reference pressure" in the storage unit 61 (see Fig. 3) (step S11).

Subsequently, the temperature of the projection optical system 35 is measured by the first temperature sensor 36. The measurement temperature of the projection optical system 35 acquired by the first temperature sensor 36 is sent to the control unit 6 and stored in the storage unit 61 as "reference temperature of the projection optical system 35". In addition, the temperature of the distance sensor 38 is measured by the second temperature sensor 37. The measurement temperature of the distance sensor 38 acquired by the second temperature sensor 37 is sent to the control unit 6 and stored in the storage unit 61 as "reference temperature of the distance sensor 38" (step S12) ).

In addition, the irradiation distance described above is measured by the distance sensor 38. The measurement irradiation distance obtained by the distance sensor 38 is sent to the control unit 6 and stored in the storage unit 61 as a "reference irradiation distance". Further, the light receiving position of the distance sensor 38 in the light receiving unit 382 is also sent to the control unit 6 and stored in the storage unit 61 as a "reference light receiving position" (step S13). Note that the execution order of steps S11 to S13 may be changed as appropriate. Moreover, two or more steps may be performed in parallel among steps S11 to S13.

Next, the focus lens group 351 is moved by the focus adjustment mechanism 353, and is positioned at a predetermined adjustment start position. The adjustment starting position is, for example, a design position of the focus lens group 351 (i.e., a design focus lens group 351 in which the focus position of the drawing head 31 will meet the upper surface 91 of the substrate 9) ) Position). Then, the light source 32 and the light modulator 34 are driven, and the jig 52 is irradiated with the predetermined calibration pattern 95 illustrated in FIG. 8. In the example shown in Fig. 8, the calibration pattern 95 is four light spots arranged in a grid. The calibration pattern 95 is not limited to the shape of FIG. 8 and may be changed in various ways.

The imaging unit 51 captures the calibration pattern 95 that has passed through the jig 52 and sends the acquired image to the control unit 6. At the time of imaging by the imaging unit 51, since the illumination light is not irradiated with respect to the above mark on the jig 52, the image acquired by the imaging unit 51 includes the image of the calibration pattern 95, , The mark on the jig 52 is not included. In the control unit 6, the contrast evaluation value is obtained by the image processing unit 62 (see FIG. 3) based on the image of the calibration pattern 95 acquired by the imaging unit 51. The contrast evaluation value is, for example, the maximum value of the differential value of contrast at the edge of the light spot of the calibration pattern 95.

In the drawing device 1, the position of the focus lens group 351 is changed by the focus adjustment mechanism 353, the imaging of the calibration pattern 95 by the imaging unit 51, and contrast by the image processing unit 62. The acquisition of the evaluation value is repeated a predetermined number of times (two or more times) (step S14). The above-mentioned position change of the focus lens group 351 is performed by a step movement that moves by a predetermined distance. The predetermined distance is, for example, four times the depth of focus pulse when the moving distance of the focus lens group 351 corresponding to the depth of half the depth of focus of the drawing head 31 is called a “focus depth pulse”.

In the image processing unit 62, the contrast evaluation value and the focus lens group 351 are based on the obtained plurality of contrast evaluation values and a plurality of positions of the focus lens group 351 corresponding to the plurality of contrast evaluation values. "Lens position-contrast data" indicating the relationship between positions is created (step S15). Then, on the basis of the lens position-contrast data, peak detection processing of the contrast evaluation value is performed by the image processing unit 62 (step S16). The peak detection processing in step S16 is performed, for example, by extracting data in the vicinity of the peak from the lens position-contrast data, and quadrangically approximating the extracted data to obtain an extreme value. The peak detection processing may be performed by various other methods.

When the peak of the contrast evaluation value is detected in step S16 (step S17), the position of the focus lens group 351 corresponding to the peak is stored in the storage unit 61 as a "reference position" (step S18), The adjustment of the autofocus mechanism ends normally.

On the other hand, when the peak of the contrast evaluation value is not detected in step S16 (step S17), it is confirmed that the number of movements of the focus lens group 351 has not reached the upper limit (step S19), and the focus adjustment mechanism 353 is used. By changing the position of the focus lens group 351, the imaging of the calibration pattern 95 by the imaging unit 51, and the acquisition of the contrast evaluation value by the image processing unit 62 are performed once (step S20). The movement distance of the focus lens group 351 in step S20 is smaller than the movement distance in step S14, and is, for example, a distance equivalent to a focus depth pulse.

Then, the process returns to step S15, new lens position-contrast data including the contrast evaluation value acquired in step S20 is created (step S15), and peak detection processing of the contrast evaluation value is performed (step S16). When the peak of the contrast evaluation value is detected, the reference position of the focus lens group 351 is stored in the storage unit 61 as described above, and the adjustment of the autofocus mechanism is normally ended (steps S17, S18). On the other hand, when the peak of the contrast evaluation value is not detected (step S17), steps S19, S20, S15 to S17 are repeated until the number of movements of the focus lens group 351 reaches the upper limit. Then, when the peak of the contrast evaluation value is not detected even when the number of movements of the focus lens group 351 reaches the upper limit, an error warning of abnormal termination is issued to the operator of the drawing device 1, etc., and adjustment of the autofocus mechanism is performed. This ends.

When the adjustment of the autofocus mechanism ends normally, drawing to the substrate 9 is performed. 7 is a diagram showing an example of the flow of drawing to one substrate 9. In the drawing device 1, first, correction of the reference position of the focus lens group 351 and correction of the reference light receiving position of the distance sensor 38 according to changes in pressure and temperature from the time of adjustment of the autofocus mechanism are performed. After being carried out, drawing on the substrate 9 is performed. As described above, in the drawing device 1, after adjusting the autofocus mechanism, drawing to the plurality of substrates 9 is continuously performed. Therefore, immediately after the adjustment of the autofocus mechanism, the correction amount for the reference position of the focus lens group 351 and the reference light receiving position of the distance sensor 38 is relatively small, but when the elapsed time from the adjustment end of the autofocus mechanism becomes large, The correction amount may be relatively large.

When writing to the substrate 9 is performed, the drawing head 31 is positioned above the substrate 9 as shown in FIG. 4. Then, the pressure (that is, air pressure) is measured by the pressure sensor 41, and the measurement pressure obtained by the pressure sensor 41 is sent to the head control unit 63 of the control unit 6 (step S31). ). Moreover, the temperature measurement by the 1st temperature sensor 36 and the 2nd temperature sensor 37 is performed, and the projection optical system 35 acquired by the 1st temperature sensor 36 and the 2nd temperature sensor 37 The measurement temperature and the measurement temperature of the distance sensor 38 are sent to the head control unit 63 (step S32). Note that the execution order of steps S31 and S32 may be changed as appropriate. Moreover, step S31 and step S32 may be performed in parallel.

In the head control unit 63, correction of the reference position of the focus lens group 351 is performed based on the measurement pressure obtained in steps S31 and S32 and the measurement temperature of the projection optical system 35 (step S33). Then, by the focus adjustment mechanism 353, the focus lens group 351 is moved to the reference position after correction (hereinafter referred to as "corrected reference position") (step S34). In step S33, the focus lens group 351 is moved from the reference position by, for example, the correction distance dF (nm) shown in equation (1).

dF = Kp × dP + Kt1 × dT1 ㆍ ㆍ ㆍ (Equation 1)

DP in Equation (1) is a pressure difference (hPa) which is a difference between the reference pressure and the measurement pressure obtained in step S31, and Kp is a coefficient (nm) indicating the moving distance of the focus lens group 351 per unit pressure difference / hPa). Moreover, dT1 in Formula 1 is the temperature difference (deg) of the projection optical system 35 which is the difference between the said reference temperature of the projection optical system 35 and the measurement temperature of the projection optical system 35 acquired in step S32, Kt1 is a coefficient (nm / deg) indicating the moving distance of the focus lens group 351 per unit temperature difference of the projection optical system 35.

The coefficients Kp and Kt1 are acquired in advance and stored in the storage unit 61. The coefficient Kp is, for example, the above-mentioned focus calibration is performed in a plurality of states in which the pressure in the housing of the drawing device 1 measured by the pressure sensor 41 is different, the change in pressure and the focus lens group The relationship of the change in the position of (351) is approximated linearly, and then determined as the slope of the approximation curve. The coefficient Kt1 is, for example, the above-mentioned focus calibration is performed in a plurality of states in which the temperatures of the projection optical system 35 measured by the first temperature sensor 36 are different, and the temperature change and the focus lens group are performed. The relationship of the change in the position of (351) is approximated linearly, and then determined as the slope of the approximation curve.

In addition, the head control unit 63 corrects the reference light receiving position in the light receiving unit 382 of the distance sensor 38 based on the measurement temperature of the distance sensor 38 acquired in step S32 (step) S35). In step S35, for example, the reference light receiving position is shifted by the correction distance dD (pixel) shown in equation (2). In the following description, the reference light receiving position after correction is called a correction reference light receiving position.

dD = Kt2 × dT2 ㆍ ㆍ ㆍ (Equation 2)

DT2 in Equation 2 is the temperature difference (deg) of the distance sensor 38 which is the difference between the reference temperature of the distance sensor 38 and the measurement temperature of the distance sensor 38 obtained in step S32, and Kt2 is , Is a coefficient (pixel / deg) indicating the moving distance of the reference light receiving position per unit temperature difference of the distance sensor 38.

The coefficient Kt2 is acquired in advance and stored in the storage unit 61. The coefficient Kt2 is obtained as follows, for example. First, in a plurality of states in which the temperature of the distance sensor 38 measured by the second temperature sensor 37 is different, the jig 52 (see FIG. 5) is provided from the light emitting unit 381 of the distance sensor 38. The light is emitted toward the light, and the reflected light from the upper surface of the jig 52 is received by the light receiving unit 382 to obtain a light receiving position. Then, the relationship between the change in temperature and the change in the light receiving position in the light-receiving portion 382 is linearly approximated, and the slope of the approximation curve is determined as the coefficient Kt2.

In the state where the focus lens group 351 is positioned at the corrected reference position, the focal position of the drawing head 31 meets the upper surface 91 of the substrate 9 without deformation such as warpage (that is, the substrate 9) Is located at the same position in the vertical direction of the upper surface 91 of). In addition, in the distance sensor 38, light emitted from the light emitting portion 381 and reflected from the upper surface 91 of the substrate 9 without deformation such as warping is received at the correction reference light receiving position of the light receiving portion 382. do. Note that the execution order of steps S33 to S34 and step S35 may be changed as appropriate. Note that steps S33 to S34 and step S35 may be executed in parallel.

In the drawing device 1, for each of the plurality of drawing heads 31, when the steps S32 to S35 are completed, the stage movement mechanism 22 is controlled by the movement control unit 64, and the Y of the substrate 9 Movement in the direction is started. In addition, in each drawing head 31, the light modulation section 34 is controlled by the head control section 63 based on the drawing data stored in advance in the storage section 61, and the moving substrate 9 The modulated light is irradiated from each drawing head 31 to the upper surface 91 to perform pattern drawing (step S36).

During the drawing of the pattern on the substrate 9, as described above, the autofocus by the distance sensor 38, the focus adjustment mechanism 353, the head control unit 63, and the like is parallel to the drawing on the substrate 9 It is carried out continuously. Specifically, while imaging on the substrate 9 is being performed, the measurement of the irradiation distance by the distance sensor 38 is continuously performed. In the measurement of the irradiation distance, a shift amount from the correction reference light receiving position of the light receiving position in the light receiving unit 382 is obtained, and based on the shift amount, a shift amount from the reference irradiation distance of the measurement irradiation distance (that is, the substrate ( The amount of deformation in the vertical direction of the upper surface 91 of 9) is obtained.

Then, the focus adjustment mechanism 353 is controlled by the head control unit 63 based on the amount of shift from the reference irradiation distance of the measurement irradiation distance, and the focus lens group 351 moves the distance corresponding to the amount of shift. As much as it is shifted from the calibration reference position. The position change of the focus lens group 351 is also performed continuously in parallel with drawing to the substrate 9. Thereby, the focal position of the drawing head 31 is moved in the vertical direction, and is aligned with the upper surface 91 of the substrate 9. As a result, even if a deformation such as bending occurs on the substrate 9, since the focal position of the drawing head 31 can be continuously adjusted to the upper surface 91 of the substrate 9, the substrate 9 High-precision drawing is realized.

In the drawing device 1, as described above, drawing to a plurality of substrates 9 is continuously performed, and at the start of drawing of each substrate 9, steps S31 to S35 described above are performed. Thereby, during continuous drawing to the plurality of substrates 9, at least of the pressure around the drawing head 31 (ie, the pressure in the clean room), the temperature of the projection optical system 35, and the temperature of the distance sensor 38, at least Even in the case where one or more changes occur, high-precision drawing for each substrate 9 is realized.

In addition, in the drawing device 1, steps S31 to S35 are not necessarily performed at the start of drawing of each substrate 9. Steps S31 to S35 are performed, for example, at the start of drawing of one substrate 9, and are not performed until the drawing of the predetermined number of substrates 9 is finished, and the specified number of substrates 9 ) May be carried out at the start of drawing to the next substrate 9 after completion of drawing to. Moreover, it is preferable that adjustment of the autofocus mechanism of steps S11-S20 is performed, for example, at the start-up of the drawing device 1 and at the end of the drawing of the predetermined number of lots on the substrate 9.

As described above, the drawing device 1 includes a stage 21, a drawing head 31, a stage moving mechanism 22, a pressure sensor 41, and a head control unit 63. The stage 21 holds the substrate 9. The drawing head 31 irradiates the modulated light to the substrate 9. The stage movement mechanism 22 moves the stage 21 relative to the drawing head 31 in a direction parallel to the upper surface 91 of the substrate 9. The pressure sensor 41 measures the pressure around the drawing head 31. The head control unit 63 controls the drawing head 31. The drawing head 31 includes a light source 32, a light modulation device 341, and a projection optical system 35. Light from the light source 32 is guided to the light modulation device 341. The projection optical system 35 directs the light modulated by the light modulation device 341 to the stage 21. The projection optical system 35 includes an objective lens group 352, a focus lens group 351, and a focus adjustment mechanism 353. The focus adjustment mechanism 353 adjusts the focus position of the drawing head 31 by changing the position of the focus lens group 351 on the optical axis. The head control unit 63 controls the focus adjustment mechanism 353 based on the output from the pressure sensor 41.

Thereby, the shift | offset | difference of the focus position of the drawing head 31 resulting from the pressure fluctuation around the drawing head 31 can be corrected. As a result, the focal position of the drawing head 31 can be adjusted to the upper surface 91 of the substrate 9 with good precision, and high-precision drawing with respect to the substrate 9 can be realized. In addition, in the drawing device 1, after performing the adjustment (so-called focus calibration) of the autofocus mechanism shown in steps S11 to S20 described above once, the calculation processing by the head control unit 63 is performed instead of the focus calibration. Since the shift of the focus position can be corrected, the time required for the correction of the shift of the focus position can be shortened. As a result, productivity of the drawing device 1 can be improved.

As described above, it is preferable that the drawing head 31 further includes a first temperature sensor 36 that measures the temperature of the projection optical system 35. Moreover, it is preferable that the control of the focus adjustment mechanism 353 by the head control unit 63 is also performed based on the output from the first temperature sensor 36. Thereby, the shift | offset | difference of the focus position of the drawing head 31 resulting from the temperature fluctuation of the projection optical system 35 can be corrected. As a result, the accuracy of drawing with respect to the substrate 9 can be improved.

As described above, it is preferable that the drawing head 31 further includes a distance sensor 38 that measures the distance to the substrate 9 on the stage 21. In addition, while the stage 21 is moved relative to the stage 21 by the stage movement mechanism 22, the area of the substrate 9 is drawn by scanning the irradiation region of the light from the drawing head 31 on the substrate 9 Measurement of the distance to the substrate 9 by the sensor 38 is continuously performed, and control of the focus adjustment mechanism 353 by the head control unit 63 is also performed based on the output from the distance sensor 38. It is desirable to be. In addition, while writing to the substrate 9 is being performed, the focus position of the drawing head 31 is controlled by the focus control mechanism 353 by the head control unit 63 so that the focus position of the drawing head 31 is the upper surface of the substrate 9 ( 91). As described above, by autofocusing during drawing on the substrate 9, high-precision drawing can also be realized on the substrate 9 where deformation such as warping occurs.

More preferably, the drawing head 31 further includes a second temperature sensor 37 that measures the temperature of the distance sensor 38, and the head control unit 63 controls the focus adjustment mechanism 353. Is performed based on the output from the second temperature sensor 37 as well. Thereby, the shift | offset | difference of the light-receiving position in the light-receiving part 382 resulting from the temperature fluctuation of the distance sensor 38 (namely, the shift | offset | difference of the measurement irradiation distance acquired by the distance sensor 38) can be corrected. As a result, the accuracy of drawing with respect to the substrate 9 can be improved.

As described above, in the drawing device 1, the stage 21 is moved relative to the stage 21 by the stage moving mechanism 22, so that the irradiation area of the light from the drawing head 31 is set on the substrate 9 in a predetermined scanning direction. It is preferable that the imaging of the substrate 9 is completed by scanning only once. In order to realize such a single pass method, it is necessary for the projection optical system 35 to have a relatively large lens. In a large lens, since the depth of focus is generally shallow, the focal position of the drawing head 31 is easily shifted from the upper surface 91 of the substrate 9. As described above, in the drawing device 1, since the focal position of the drawing head 31 can be accurately adjusted to the upper surface 91 of the substrate 9, the structure of the drawing device 1 is single. It is particularly suitable for a drawing device in which a pass type drawing is performed.

As described above, preferably, the pattern drawn on the substrate 9 is a circuit pattern, the L / S line of the circuit pattern is 7 µm to 9 µm, and the space is 11 µm to 13 µm. In order to realize such high-definition drawing, the projection optical system 35 needs to have a relatively large lens. In a large lens, since the depth of focus is generally shallow, the focal position of the drawing head 31 is easily shifted from the upper surface 91 of the substrate 9. As described above, in the drawing device 1, since the focal position of the drawing head 31 can be accurately adjusted to the upper surface 91 of the substrate 9, the structure of the drawing device 1 is fixed. It is particularly suitable for a drawing device in which three paintings are performed.

As described above, the focus lens group 351 is preferably moved independently from the objective lens group 352 by the focus adjustment mechanism 353. Thereby, the focus adjustment mechanism 353 can be downsized. The structure in which the focus lens group 351 is independently moved from the objective lens group 352 is particularly suitable for a drawing device in which the focus lens group 351 has a relatively large lens.

Moreover, it is more preferable that the moving direction of the focus lens group 351 by the focus adjustment mechanism 353 is a horizontal direction. As a result, even if the focus lens group 351 is enlarged and has a large weight, it is possible to facilitate the movement of the focus lens group 351 by the focus adjustment mechanism 353, compared to the case where the movement direction is the vertical direction. have.

The drawing method in which the substrate 9 is irradiated with light by the drawing device 1 to draw a pattern includes steps of measuring the pressure around the drawing head 31 (step S31) and pressure measured in step S31. On the basis of this, a step (step S33) of adjusting the focus position of the drawing head 31 by changing the position of the focus lens group 351 on the optical axis is provided. Thereby, as mentioned above, the shift | offset | difference of the focus position of the drawing head 31 resulting from the pressure fluctuation around the drawing head 31 can be corrected. As a result, the focal position of the drawing head 31 can be adjusted to the upper surface 91 of the substrate 9 with good precision, and high-precision drawing with respect to the substrate 9 can be realized.

In the drawing apparatus 1, also in the process of adjusting the displacement in the horizontal direction of the irradiation position of the light from the drawing head 31 and the corresponding irradiation position in design (so-called head calibration), the pressure and temperature described above are also applied. It is preferable that the correction based on it is carried out. The head calibration is performed, for example, during maintenance of the drawing device 1. When the head calibration is performed, the drawing head 31 to be adjusted is moved upward of the jig 52, and the imaging unit 51 is located below the drawing head 31.

9 is a view showing an example of the flow of head calibration. First, the pressure (i.e., air pressure) is measured by the pressure sensor 41, and the measurement pressure obtained by the pressure sensor 41 is sent to the head control unit 63 of the control unit 6 (step S41) ). Moreover, temperature measurement by the 1st temperature sensor 36 is performed, and the measurement temperature of the projection optical system 35 acquired by the 1st temperature sensor 36 is sent to the head control part 63 (step S42). . Note that the execution order of steps S41 and S42 may be changed as appropriate. Moreover, step S41 and step S42 may be performed in parallel.

In the head control unit 63, the reference position of the focus lens group 351 is corrected based on the measurement pressure obtained in steps S41 and S42 and the measurement temperature of the projection optical system 35 (step S43). Then, the focus lens group 351 is moved to the correction reference position by the focus adjustment mechanism 353 (step S44). In step S43, the focus lens group 351 is moved from the reference position by the correction distance dF (nm) shown in equation (1), similarly to step S33 described above. Thereby, the focal position of the drawing head 31 is adjusted to the upper surface of the jig 52.

When the focus lens group 351 is positioned at the corrected reference position, light is irradiated from the drawing head 31 to the jig 52, and a predetermined calibration pattern (not shown) is irradiated to the jig 52. Then, by the imaging unit 51, an irradiation region of light from the drawing head 31 on the jig 52 is imaged together with the above-described marks previously formed on the jig 52 (step S45). . The illumination light is irradiated from the light source fixed to the distance sensor 38, for example.

The image acquired by the imaging unit 51 is sent to the image processing unit 62 of the control unit 6. The image processing unit 62, based on the image acquired by the imaging unit 51, the irradiation position of the actual drawing head 31 and the irradiation position of the design drawing head 31 (hereinafter referred to as "design irradiation position" ”Is obtained. In other words, based on the image acquired in step S45, the image processing unit 62 acquires a shift in the horizontal direction from the design irradiation position of the irradiation position of the drawing head 31 (step S46).

Then, based on the said shift, the drawing head 31 is moved in the horizontal direction by a head movement mechanism (not shown) so that the irradiation position of the drawing head 31 matches the design irradiation position (step S47). In the drawing device 1, the above-described steps S41 to S47 are performed on each of the plurality of drawing heads 31, thereby adjusting the position of the plurality of drawing heads in the horizontal direction (that is, head calibration). ) Ends.

As described above, the drawing device 1 preferably further includes a jig 52, an imaging unit 51, and an image processing unit 62. The jig 52 is fixed to the stage 21. The imaging unit 51 captures the irradiation region of the light from the drawing head 31 on the jig 52 together with a mark previously formed on the jig 52. Based on the image acquired by the imaging unit 51, the image processing unit 62 acquires a shift in the irradiation position of the drawing head 31 from the design irradiation position. In the drawing device 1, when imaging of the jig 52 by the imaging unit 51 is performed, the focus of the drawing head 31 is controlled by the focus adjustment mechanism 353 by the head control unit 63 It is preferred that the position is fitted to the jig 52. Thereby, since the deviation of the irradiation position of the drawing head 31 from the design irradiation position can be acquired with high precision, high-precision head calibration can be realized. As a result, the accuracy of drawing with respect to the substrate 9 can be improved.

In the above-described writing device 1 and drawing method, various changes are possible.

The first temperature sensor 36 need not be affixed to the position illustrated in FIG. 4, but may be attached to, for example, another portion of the objective lens group 352 or the focal lens group 351. Likewise, the second temperature sensor 37 need not be attached to the position illustrated in FIG. 4, but may be attached to, for example, the light emitting portion 381 or the light receiving portion 382. The first temperature sensor 36 and the second temperature sensor 37 may be sensors other than a thermocouple. The position and type of the pressure sensor 41 may also be changed as appropriate.

In the drawing head 31, instead of DMD, other apparatuses such as GLV (Grating Light Valve) (registered trademark), for example, may be formed as the light modulation device 341.

In addition, in the drawing head 31, the focus lens group 351 is not necessarily moved independently from the objective lens group 352, and is moved together with the objective lens group 352 by the focus adjustment mechanism 353. You may work.

In the adjustment of the autofocus mechanism described above, in step S14, parameters other than the contrast evaluation value are obtained from the image acquired by the imaging unit 51, and the peak detection processing in step S16 is obtained using the parameters. May be carried out. Moreover, the acquisition of the reference pressure, the reference temperature, and the reference light receiving position in steps S11 to S13 may be performed after the reference position of the focus lens group 351 is acquired in step S18.

The correction of the reference position of the focus lens group 351 in step S33 may be performed using an equation other than equation (1). Alternatively, a table showing the relationship between the pressure around the drawing head 31 and the temperature of the projection optical system 35 and the position of the focal lens group 351 is stored in the storage unit 61 in advance, and the table is used. The reference position of the focus lens group 351 may be corrected. In the correction of the reference position of the focus lens group 351, the temperature of the projection optical system 35 does not necessarily need to be used, for example, the correction may be performed based only on the pressure around the drawing head 31. The same applies to correction of the reference position of the focus lens group 351 in step S43.

The correction of the reference light receiving position in step S35 may be performed using an equation other than equation (2). Alternatively, a table showing the relationship between the temperature of the distance sensor 38 and the reference light receiving position is previously stored in the storage unit 61, and the table may be used to correct the reference light receiving position. Further, correction of the reference light receiving position of the distance sensor 38 may be omitted.

The drawing of the substrate 9 in the drawing device 1 is not necessarily performed in a single pass method, but may be performed in a so-called multi-pass method. In this case, first, the substrate 9 is moved in the Y direction by the stage moving mechanism 22, so that the irradiation region of the light from the plurality of drawing heads 31 is in the Y direction on the upper surface 91 of the substrate 9 Is injected. Subsequently, the substrate 9 is moved by the stage movement mechanism 22 in the X direction by a predetermined distance (for example, a distance substantially equal to the drawing width by one drawing head 31). Next, the substrate 9 is moved again in the Y direction, and the irradiation region of the light from the plurality of drawing heads 31 is scanned in the Y direction on the upper surface 91 of the substrate 9. Then, scanning of light by movement of the substrate 9 in the Y-direction (i.e., scanning direction) and step movement of the substrate 9 in the X-direction (i.e., width direction) are repeated, thereby providing the Drawing of the circuit pattern for Korea is performed.

The stage movement mechanism 22 does not necessarily need to move the stage 21, for example, in the upper side of the fixed stage 21, the plurality of drawing heads 31, the upper surface of the substrate 9 You may move in the direction parallel to (91).

The number of the drawing heads 31 formed in the drawing section 3 may be changed as appropriate. The number of drawing heads 31 may be one or two or more.

In the drawing device 1, the L / S of the circuit pattern drawn on the substrate 9 may be changed as appropriate. Further, patterns other than the circuit pattern may be drawn on the substrate 9.

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

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

Although the invention has been described in detail and described, the descriptions already described are illustrative and not restrictive. Therefore, it can be said that many modifications and aspects are possible without departing from the scope of the present invention.

1: Drawing device
9: Substrate
21: Stage
22: stage moving mechanism
31: drawing head
32: light source
35: projection optical system
36: first temperature sensor
37: second temperature sensor
38: distance sensor
41: pressure sensor
51: imaging unit
52: jig
62: image processing unit
63: head control
91: (on the substrate) top
341: optical modulation device
351: focus lens group
352: objective lens group
353: focus adjustment mechanism
S11 to S20, S31 to S36, S41 to S47: Step

Claims (16)

A drawing device for irradiating light onto a substrate to draw a pattern,
A stage for holding the substrate,
A drawing head for irradiating modulated light to the substrate;
A stage movement mechanism for moving the stage relative to the drawing head in a direction parallel to the upper surface of the substrate;
And a pressure sensor for measuring the pressure around the drawing head,
It has a head control unit for controlling the drawing head,
The drawing head,
Light Source,
A light modulation device through which light from the light source is derived,
And a projection optical system for guiding light modulated by the light modulation device to the stage,
The projection optical system,
The objective lens group,
Focal lens group,
And a focus adjustment mechanism for adjusting the focus position of the drawing head by changing the position on the optical axis of the focus lens group,
The head control unit controls the focus adjustment mechanism based on the output from the pressure sensor. According to claim 1,
The drawing head further includes a first temperature sensor for measuring the temperature of the projection optical system,
The drawing device is characterized in that the control of the focus adjustment mechanism by the head control unit is also performed based on the output from the first temperature sensor. According to claim 1,
The drawing head further includes a distance sensor for measuring the distance to the substrate on the stage,
While the imaging is performed on the substrate by moving the stage relative to the stage by the stage moving mechanism and scanning the irradiation area of the light from the drawing head on the substrate, the distance sensor measures the distance to the substrate. Is carried out continuously,
Control of the focus adjustment mechanism by the head control unit is performed based on output from the distance sensor,
The drawing apparatus characterized in that while the drawing to the substrate is being performed, the focus position of the drawing head is aligned with the upper surface of the substrate by the control of the focus adjustment mechanism by the head control unit. The method of claim 3,
The drawing head further includes a second temperature sensor that measures the temperature of the distance sensor,
The drawing apparatus is characterized in that the control of the focus adjustment mechanism by the head control unit is also performed based on the output from the second temperature sensor. According to claim 1,
A jig fixed to the stage,
An imaging unit for imaging an irradiation region of light from the drawing head on the jig together with a mark previously formed on the jig,
On the basis of the image acquired by the imaging section, an image processing section for acquiring a deviation from the design irradiation position of the irradiation position of the drawing head is further provided,
When the imaging of the jig is carried out by the imaging unit, the drawing device is characterized in that the focus position of the drawing head is adjusted to the jig by control of the focus adjustment mechanism by the head control unit. According to claim 1,
The imaging apparatus characterized in that the imaging is completed on the substrate by moving the stage relative to the stage by the stage moving mechanism to scan the light irradiation area from the drawing head only once in the predetermined scanning direction on the substrate. According to claim 1,
The patterning device to be drawn on the substrate is a circuit pattern, the L / S line of the circuit pattern is 7 µm to 9 µm, and the space is 11 µm to 13 µm. The method according to any one of claims 1 to 7,
The focusing lens group is independently drawn from the objective lens group by the focus adjustment mechanism. A drawing device comprising a stage for holding a substrate, a drawing head for irradiating modulated light to the substrate, and a stage moving mechanism for moving the stage relative to the drawing head in a direction parallel to the upper surface of the substrate. As a drawing method for irradiating light onto a substrate to draw a pattern,
The drawing head,
Light Source,
A light modulation device through which light from the light source is derived,
And a projection optical system for guiding light modulated by the light modulation device to the stage,
The projection optical system,
The objective lens group,
It has a focus lens group,
a) measuring the pressure around the drawing head,
b) a drawing method comprising adjusting the focus position of the drawing head by changing the position on the optical axis of the focus lens group based on the pressure measured in the step a). The method of claim 9,
c) further comprising a process for measuring the temperature of the projection optical system,
The adjustment of the focal position of the drawing head in the step b) is performed based on the temperature measured in the step c). The method of claim 9,
d) In the step b), after the focal position of the drawing head is aligned with the upper surface of the substrate, the stage is moved relative to the stage to scan the irradiation area of the light from the drawing head on the substrate A process of drawing the substrate by doing so,
e) in parallel with the step d), a step of continuously measuring the distance from the drawing head to the substrate on the stage,
f) In parallel with the step d), by changing the position on the optical axis of the focus lens group based on the distance measured in the step e), the focus position of the drawing head is brought to the upper surface of the substrate. A drawing method characterized by further comprising a step of continuously fitting. The method of claim 11,
g) further comprising a step of measuring the temperature of the distance sensor used for measuring the distance from said step e) to said substrate,
The adjustment of the focal position of the drawing head in the step b) is performed based on the temperature measured in the step g). The method of claim 9,
The drawing device,
A jig fixed to the stage,
Further provided with an imaging unit for imaging the jig,
The drawing method,
h) In the step b), after the focal position of the drawing head is aligned with the jig, an irradiation area of light from the drawing head on the jig is imaged together with a mark previously formed on the jig. The process to do,
i) A drawing method further comprising a step of acquiring a deviation from the design irradiation position of the irradiation position of the drawing head based on the image obtained in the step h). The method of claim 9,
The writing method for the substrate is completed by moving the stage relative to the stage by the stage moving mechanism to scan the irradiation region of light from the drawing head only once in a predetermined scanning direction on the substrate. The method of claim 9,
The patterning method for drawing on the substrate is a circuit pattern, the L / S line of the circuit pattern is 7 µm to 9 µm, and the space is 11 µm to 13 µm. The method according to any one of claims 9 to 15,
In the step b), the focusing lens group moves independently from the objective lens group.

Images