JP6828766B2 - Pattern drawing device - Google Patents

Description

The present invention relates to a pattern drawing apparatus that draws a pattern by irradiating an irradiated body such as a substrate with a light beam based on drawing data.

In recent years, called printable electronic, printing methods such as intaglio method, letterpress method, silk method, or inkjet method, or flexible printing method on a flexible substrate made of resin or ultra-thin glass. Attempts have been made to form electronic devices such as display displays by an optical patterning method in which an ultraviolet light pattern is projected onto a photosensitive layer coated on a substrate. For the formation of a circuit pattern (single wiring layer or multilayer wiring layer) including a thin film (TFT), an IC chip, a sensor element, a resistance element, a capacitor element, etc. as an electronic device, the drawing resolution of the pattern is high and high. Since accurate positioning accuracy is required, it is considered to use an optical patterning method instead of a printing method.

In Patent Document 1 shown below, a laser beam is irradiated onto a base material according to drawing data defined by a predetermined inter-pixel pitch (pixel size), and the beam and the base material are relatively moved two-dimensionally. A pattern forming apparatus for forming a pattern such as a TFT or a color filter on a base material is disclosed. In the pattern forming apparatus of Patent Document 1, each position of the alignment mark formed at a plurality of places around the pre-process pattern formed on the base material (flexible base material) is detected, and the base material is based on the result. By obtaining the expansion and contraction (and deformation) of the pattern and correcting the drawing data according to the obtained expansion and contraction (deformation), pattern exposure is performed in which the positional deviation from the previous process pattern is prevented. When correcting the drawing data, the dimensions (pixels) of the pixels are subdivided into the direction in which the beam is moved on the base material (main scanning direction) and the moving direction of the moving stage supporting the base material (secondary scanning direction). The pitch) is corrected according to the expansion and contraction of the base material.

However, for example, when a pattern is continuously formed on a long base material by a roll-to-roll method, the expansion and contraction of the base material in the long length direction is not constant and may fluctuate in some places. That is, even within the pattern forming region (exposure region) corresponding to one electronic device formed on the long base material, the expansion and contraction in the sub-scanning direction may not be constant, and 1 on the base material. In order not to deteriorate the overlay accuracy with the base pattern (previous process pattern) and the total pitch accuracy (dimensional accuracy of the entire length of the pattern formation area) even while the pattern is being drawn in one pattern formation area, it is secondary. It becomes necessary to finely change the magnification correction regarding the scanning direction.

Japanese Unexamined Patent Publication No. 2004-272167

One aspect of the present invention has a drawing head portion that sequentially deflects a drawing beam on each reflecting surface of a rotating polymorphic mirror and repeatedly scans the spot light of the drawing beam in the main scanning direction on the substrate. the drawing head portion by relatively moving in the sub-scanning direction, a pattern drawing apparatus for drawing a pattern on the substrate for each drawing lines formed by the main scanning direction of the scanning of the spot light and the the time at which each of the reflecting surfaces of the rotating polygon mirror becomes a predetermined angle detected optically, a detection signal indicating that the spot light of the drawing beam becomes a scanning start position in the main scanning direction, the spots a detection sensor for outputting at every said repetition scanning light, the drawing data to which the spot light corresponding to the pattern to be drawn while being scanned in the main scanning direction, are formed side by side in the sub scanning direction wherein a data storage unit for storing a plurality to correspond to each of the plurality of drawing lines, the first of the detection signal output from the first said detection sensor corresponding to the reflection surface of said rotary polygonal mirror and the subsequently The second detection signal stored in the data storage unit during a period between the second detection signal output from the detection sensor corresponding to the second reflection surface of the rotating polymorphic mirror and the second detection signal output from the detection sensor. A preparatory process for preparing the drawing data corresponding to the drawing line to be drawn in response to is executed, and the spot light is based on the drawing data prepared in response to the second detection signal. It is provided with a control unit for controlling the drawing of the pattern according to the above.

It is a figure which shows the whole structure of the exposure apparatus by 1st Embodiment. It is a detailed view which shows the state which the substrate is wound around the rotating drum of the exposure apparatus shown in FIG. It is a figure which shows the drawing line of the spot light scanned on the substrate, and the alignment mark formed on the substrate. It is a figure which shows the optical structure of the scanning unit shown in FIG. It is a figure which shows the structure of the beam distribution part shown in FIG. It is a block diagram which shows the schematic structure of the control device shown in FIG. It is a figure which shows the specific structure of the light source apparatus shown in FIG. It is a figure explaining the timing of reading drawing data (pixel data string) according to the moving position (moving amount) of a substrate by the drawing control unit and the drawing data storage unit shown in FIG. FIG. 9A is a diagram showing a state in which the increment of the X address value (increment of address 1) corresponds to 10 counts of the movement amount when the magnification correction is not performed, and FIG. 9B is a diagram showing a pattern to be drawn. It is a figure which shows the state which the increment (the increase of the address 1) of the X address value corresponds to 9 counts of the movement amount in order to reduce. It is a figure explaining the control when changing to a different drawing magnification in the middle of a drawing operation. It is a figure explaining the control when changing to a different drawing magnification in the middle of a drawing operation. It is a figure explaining an example of the magnification change point set on one exposure area. 6 is a time chart for explaining a modification of the calculation sequence for correcting the drawing magnification in the sub-scanning direction executed by the drawing control unit shown in FIG. This is a time chart showing the generation timing, drawing timing, and calculation timing of the origin signal from the scanning unit in chronological order. FIG. 6 is a block diagram illustrating an outline of a partial circuit configuration provided in each of the drawing control unit and the drawing data storage unit in FIG. 6 in order to perform the control described in FIG. FIG. 5 is a chart diagram showing an example of a case where the position shift of the drawing pattern in the main scanning direction (Y direction) described with reference to FIGS. 14 and 15 is continuously executed during the drawing operation of the pattern with respect to the exposed area.

The pattern drawing apparatus according to the aspect of the present invention will be described in detail below with reference to the accompanying drawings, with reference to preferred embodiments. It should be noted that the aspects of the present invention are not limited to these embodiments, but include those with various changes or improvements. That is, the components described below include those that can be easily assumed by those skilled in the art and those that are substantially the same, and the components described below can be appropriately combined. In addition, various omissions, substitutions or changes of components can be made without departing from the gist of the present invention.

[First Embodiment]
FIG. 1 is a diagram showing a schematic configuration of a device manufacturing system 10 including an exposure apparatus (pattern drawing apparatus) EX that performs an exposure process on a substrate (irradiated body) P according to the first embodiment. In the following description, unless otherwise specified, an XYZ Cartesian coordinate system with the gravity direction as the Z direction is set, and the X direction, the Y direction, and the Z direction are described according to the arrows shown in the figure.

The device manufacturing system 10 is a system (board processing device) for manufacturing an electronic device by subjecting a substrate P to a predetermined process (exposure process or the like). In the device manufacturing system 10, for example, a manufacturing line for manufacturing a flexible display as an electronic device, a film-shaped touch panel, a film-shaped color filter for a liquid crystal display panel, a flexible wiring, a flexible sensor, or the like has been constructed. It is a manufacturing system. Hereinafter, a flexible display will be described as an electronic device. Flexible displays include, for example, organic EL displays, liquid crystal displays, and the like. In the device manufacturing system 10, the substrate P is delivered from a supply roll (not shown) in which a flexible sheet-shaped substrate (sheet substrate) P is wound in a roll shape, and various processes are continuously performed on the delivered substrate P. It has a so-called roll-to-roll (Roll To Roll) structure in which the substrate P after various treatments is wound up by a recovery roll (not shown). The substrate P has a strip-like shape in which the moving direction (transporting direction) of the substrate P is the longitudinal direction (long) and the width direction is the lateral direction (short). In the first embodiment, the film-shaped substrate P passes through the processing device (first processing device) PR1 in the previous process, the exposure device EX, and the processing device (second processing device) PR2 in the subsequent process. , Shows an example of continuous processing.

In the first embodiment, the X direction is a horizontal plane parallel to the floor surface E of the factory where the device is installed and the substrate P is conveyed, and the Y direction is the X direction in the horizontal plane. The direction orthogonal to, that is, the width direction (short direction) of the substrate P, and the Z direction is a direction (upward direction) orthogonal to the X direction and the Y direction, and is parallel to the direction in which gravity acts.

As the substrate P, for example, a resin film, a foil made of a metal or alloy such as stainless steel, or the like is used. Examples of the material of the resin film include polyethylene resin, polypropylene resin, polyester resin, ethylene vinyl copolymer resin, polyvinyl chloride resin, cellulose resin, polyamide resin, polyimide resin, polycarbonate resin, polystyrene resin, and vinyl acetate resin. Of these, those containing at least one may be used. Further, the thickness and rigidity (Young's modulus) of the substrate P may be within a range that does not cause creases or irreversible wrinkles due to buckling on the substrate P when passing through the transport path of the device manufacturing system 10. .. As a base material of the substrate P, a film having a thickness of about 25 μm to 200 μm, such as PET (polyethylene terephthalate) or PEN (polyethylene naphthalate), is typical of a suitable sheet substrate.

Since the substrate P may receive heat in each process performed by the processing device PR1 and the processing device PR2, it is preferable to select a substrate P made of a material whose thermal expansion coefficient is not remarkably large. For example, the coefficient of thermal expansion can be suppressed by mixing the inorganic filler with the resin film. The inorganic filler may be, for example, titanium oxide, zinc oxide, alumina, silicon oxide or the like. Further, the substrate P may be a single layer of ultrathin glass having a thickness of about 100 μm manufactured by a float method or the like, or a laminated body in which the above resin film, foil or the like is bonded to the ultrathin glass. It may be.

By the way, the flexibility of the substrate P means a property that the substrate P can be flexed without being sheared or broken even when a force of about its own weight is applied to the substrate P. .. Flexibility also includes the property of bending by a force of about its own weight. Further, the degree of flexibility varies depending on the material, size, thickness of the substrate P, the layer structure formed on the substrate P, the temperature, the environment such as humidity, and the like. In any case, when the substrate P is correctly wound around the transfer direction changing members such as various transfer rollers and rotary drums provided in the transfer path in the device manufacturing system 10 according to the first embodiment, the seat It can be said that the range of flexibility is such that the substrate P can be smoothly conveyed without bending and creases or breakage (tear or crack).

The processing device PR1 for the pre-process is a coating device that performs a coating process and a drying process on the substrate P while transporting the substrate P at a predetermined speed along a long direction. The processing device PR1 selectively or uniformly applies the photosensitive functional liquid to the surface of the substrate P, and then removes the solvent or water contained in the photosensitive functional liquid to dry the photosensitive functional liquid. As a result, a film to be a photosensitive functional layer (light sensitive layer) is selectively or uniformly formed on the surface of the substrate P. A photosensitive functional layer may be formed on the surface of the substrate P by attaching the dry film to the surface of the substrate P. In this case, instead of the processing device PR1, a sticking device (processing device) for attaching the dry film to the substrate P may be provided.

Here, a typical photosensitive functional liquid (layer) is a photoresist (liquid or dry film), but as a material that does not require development treatment, it has a liquid-repellent property in a portion irradiated with ultraviolet rays. There is a photosensitive silane coupling agent (SAM) that is modified, or a photosensitive reducing agent that exposes a plating reducing group to a portion irradiated with ultraviolet rays. When a photosensitive silane coupling agent is used as the photosensitive functional liquid (layer), the pattern portion exposed to ultraviolet rays on the substrate P is modified from liquid-repellent to liquid-friendly. Therefore, a thin film transistor (TFT) or the like can be obtained by selectively coating a conductive ink (an ink containing conductive nanoparticles such as silver or copper) or a liquid containing a semiconductor material on a portion that has become liquid-friendly. It is possible to form a pattern layer that serves as a wiring for electrodes, semiconductors, insulation, or connections constituting the above. When a photosensitive reducing agent is used as the photosensitive functional liquid (layer), the plating reducing group is exposed on the pattern portion exposed to ultraviolet rays on the substrate P. Therefore, after the exposure, the substrate P is immediately immersed in a plating solution containing palladium ions or the like for a certain period of time to form (precipitate) a pattern layer made of palladium. Such a plating process is an additive process, but an etching process as a subtractive process may be premised. In that case, the substrate P sent to the exposure apparatus EX uses PET or PEN as the base material, and a metallic thin film such as aluminum (Al) or copper (Cu) is deposited on the entire surface or selectively of the substrate P. A photoresist layer may be laminated on top of it.

The exposure apparatus EX performs exposure processing (pattern drawing) on the substrate P while conveying the substrate P conveyed from the processing apparatus PR1 toward the processing apparatus PR2 at a predetermined speed in the conveying direction (+ X direction). It is a processing device. The exposure apparatus EX has light on the surface of the substrate P (the surface of the photosensitive functional layer, that is, the photosensitive surface) according to a pattern for an electronic device (for example, a pattern of a TFT electrode or wiring constituting the electronic device). Irradiate the pattern. As a result, a latent image (modified portion) corresponding to the pattern is formed on the photosensitive functional layer.

In the first embodiment, the exposure apparatus EX is a direct drawing type exposure apparatus that does not use a mask, that is, a so-called raster scan type pattern drawing apparatus. As will be described in detail later, the exposure apparatus EX transmits the spot light SP of the pulsed beam (pulse beam, light beam) LB for exposure while transporting the substrate P in the long direction (secondary scanning direction). While scanning (main scanning) one-dimensionally in a predetermined scanning direction (Y direction) on the irradiated surface (photosensitive surface) of the substrate P, the intensity of the spot light SP is modulated at high speed according to the pattern data (drawing data). (On / off). As a result, an optical pattern corresponding to a predetermined pattern such as an electronic device, a circuit, or a wiring is drawn and exposed on the irradiated surface of the substrate P. That is, in the sub-scanning of the substrate P and the main scanning of the spot light SP, the spot light SP is relatively two-dimensionally scanned on the irradiated surface of the substrate P, and a predetermined pattern is drawn and exposed on the substrate P. .. Further, since the substrate P is conveyed along the elongated direction, a plurality of exposure regions W on which the pattern is exposed by the exposure apparatus EX are provided along the elongated direction of the substrate P at predetermined intervals. This is the case (see Fig. 3). Since the electronic device is formed in this exposure region W, the exposure region W is also a device formation region.

The processing device PR2 in the post-process is a wet processing device that performs wet treatment and drying treatment on the substrate P while transporting the substrate P conveyed from the exposure apparatus EX at a predetermined speed. In the first embodiment, the processing apparatus PR2 performs a developing process or a plating process, which is a kind of wet process, on the substrate P. Therefore, the processing device PR2 includes a developing unit for immersing the substrate P in a developing solution for a predetermined time, a plating unit for immersing the substrate P in an electroless plating solution for a predetermined time, and a cleaning unit for cleaning the substrate P with pure water or the like. And a drying portion for drying the substrate P. As a result, a pattern layer corresponding to the latent image is deposited (formed) on the surface of the photosensitive functional layer. That is, a predetermined material (for example, resist, palladium) is selectively formed on the substrate P according to the difference between the irradiated portion and the non-irradiated portion of the spot light SP on the photosensitive functional layer of the substrate P, and this is a pattern. Become a layer.

When a photosensitive silane coupling agent is used as the photosensitive functional layer, a liquid (for example, a liquid containing conductive ink or the like), which is a kind of wet treatment, is applied or plated by the processing device PR2. Will be Even in this case, a pattern layer corresponding to the latent image is formed on the surface of the photosensitive functional layer. That is, a predetermined material (for example, conductive ink or palladium) is selectively formed on the substrate P according to the difference between the irradiated portion and the irradiated portion of the spot light SP of the photosensitive functional layer of the substrate P. This becomes the pattern layer.

By the way, the exposure apparatus (pattern drawing apparatus) EX shown in FIG. 1 is stored in the temperature control chamber ECV. By keeping the inside at a predetermined temperature and a predetermined humidity, the temperature control chamber ECV suppresses the shape change due to the temperature of the substrate P transported inside, and is generated due to the hygroscopicity of the substrate P and the transport. The humidity is set in consideration of the charge of static electricity. The temperature control chamber ECV is arranged on the floor surface E of the manufacturing plant via the passive or active anti-vibration units SU1 and SU2. The vibration isolation units SU1 and SU2 reduce vibration from the floor surface E. The floor surface E may be the floor surface of the factory itself, or may be a surface on an installation base (pedestal) that is exclusively installed on the floor surface in order to create a horizontal surface. The exposure device EX includes a substrate transfer mechanism 12, a light source device LS, a beam distribution unit BDU, an exposure head 14, a control device 16, and a plurality of alignment microscopes AM1m, AM2m (note that m = 1, 2, 3, 4) and at least a plurality of encoder heads ENja and ENjb (note that j = 1, 2, 3, 4) are provided. The control device (control unit) 16 controls each unit of the exposure device EX. The control device 16 includes a computer and a recording medium or the like on which a program is recorded, and when the computer executes the program, the control device 16 functions as the control device 16 of the first embodiment.

The substrate transfer mechanism (movement mechanism) 12 constitutes a part of the substrate transfer device of the device manufacturing system 10, and the substrate P transferred from the processing device PR1 is conveyed in the exposure apparatus EX at a predetermined speed. After that, it is sent to the processing device PR2 at a predetermined speed. The substrate transfer mechanism 12 defines a transfer path for the substrate P to be conveyed in the exposure apparatus EX. The substrate transport mechanism 12 includes an edge position controller EPC, a drive roller R1, a tension adjusting roller RT1, a rotary drum (cylindrical drum) DR, and a tension adjusting roller RT2 in order from the upstream side (−X direction side) of the substrate P in the transport direction. It has a drive roller R2 and a drive roller R3.

The position of the edge position controller EPC in the width direction (Y direction and the short direction of the substrate P) of the substrate P conveyed from the processing device PR1 is in the range of ± tens of μm to several tens of μm with respect to the target position. The substrate P is moved in the width direction so as to be within the (allowable range), and the position of the substrate P in the width direction is adjusted. The edge position controller EPC finely moves the rollers of the edge position controller EPC in the Y direction based on a detection signal from an edge sensor (not shown) that detects the position of the end (edge) in the width direction of the substrate P, and the substrate. Adjust the position of P in the width direction. The drive roller (nip roller) R1 rotates while holding both the front and back surfaces of the substrate P conveyed from the edge position controller EPC, and conveys the substrate P toward the rotating drum DR. The edge position controller EPC appropriately adjusts the position of the substrate P in the width direction so that the long direction of the substrate P wound around the rotary drum DR is always orthogonal to the central axis AXo of the rotary drum DR. The parallelism between the rotation axis and the Y axis of the roller of the edge position controller EPC may be appropriately adjusted so as to correct the inclination error in the traveling direction of the substrate P.

The rotating drum DR has a central axis AXo extending in the Y direction and extending in a direction intersecting the direction in which gravity acts, and a cylindrical outer peripheral surface having a constant radius from the central axis AXo. The rotary drum DR rotates around the central axis AXo while supporting (holding) a part of the substrate P by bending it into a cylindrical surface in the elongated direction following the outer peripheral surface (circumferential surface). P is conveyed in the + X direction. The rotating drum DR supports a region (part) on the substrate P on which the beam LB (spot light SP) projected from the exposure head 14 is projected by its outer peripheral surface. The rotary drum DR supports (holds close contact) the substrate P from the surface (back surface) opposite to the surface on which the electronic device is formed (the surface on which the photosensitive layer is formed). Shafts Sft supported by annular bearings are provided on both sides of the rotating drum DR in the Y direction so that the rotating drum DR rotates around the central axis AXo. The shaft Sft rotates at a constant rotational speed around the central axis AXo by being given a rotational torque from a rotational drive source (for example, a motor, a reduction mechanism, etc.) controlled by the control device 16 (for example, a motor or a reduction mechanism). For convenience, a plane including the central axis AXo and parallel to the YZ plane is referred to as a central plane Poc.

The drive rollers (nip rollers) R2 and R3 are arranged at predetermined intervals along the transport direction (+ X direction) of the substrate P, and give a predetermined slack (play) to the substrate P after exposure. Like the drive roller R1, the drive rollers R2 and R3 rotate while holding both the front and back surfaces of the substrate P, and convey the substrate P toward the processing device PR2. The tension adjusting rollers RT1 and RT2 are urged in the −Z direction, and give a predetermined tension in the elongated direction to the substrate P which is wound around the rotating drum DR and supported. As a result, the tension applied to the substrate P on the rotary drum DR in the long direction is stabilized within a predetermined range. The control device 16 rotates the drive rollers R1 to R3 by controlling a rotation drive source (for example, a motor, a reduction mechanism, etc.) (not shown). The rotation axes of the drive rollers R1 to R3 and the rotation axes of the tension adjusting rollers RT1 and RT2 are parallel to the central axis AXo of the rotation drum DR.

The light source device LS generates and emits a pulsed beam (pulse beam, pulsed light, laser) LB. This beam LB is ultraviolet light having a peak wavelength at a specific wavelength (for example, 355 nm) in a wavelength band of 370 nm or less, and the emission frequency (oscillation frequency, predetermined frequency) of the beam LB is Fa. The beam LB emitted from the light source device LS is incident on the exposure head 14 via the beam distribution unit BDU. The light source device LS emits and emits a beam LB at a light emission frequency Fa according to the control of the control device 16. The configuration of this light source device LS will be described in detail later, but in the first embodiment, a semiconductor laser element that generates pulsed light in the infrared wavelength region, a fiber amplifier, and an amplified infrared wavelength region. It is composed of a wavelength conversion element (harmonic generator) that converts pulsed light into pulsed light in the ultraviolet wavelength range, and can emit pulses at an oscillation frequency Fa of 100 MHz to several hundred MHz, and the emission time of one pulsed light is It is assumed that a fiber amplifier laser light source (harmonic laser light source) capable of obtaining high-intensity ultraviolet pulsed light of several picoseconds to ten and several picoseconds is used.

The beam distribution unit BDU distributes the beam LB from the light source device LS to each of the plurality of scanning units Un (n = 1, 2, ..., 6) constituting the exposure head 14. It has a splitter and a drawing optical element (AOM) that modulates the intensity of each of the beam LBn incident on each scanning unit Un according to the drawing data. Details thereof will be described later with reference to FIG.

The exposure head (exposure head unit) 14 is a so-called multi-beam type exposure head in which a plurality of scanning units Un (U1 to U6) having the same configuration are arranged. The exposure head 14 draws a pattern on a part of the substrate P supported by the outer peripheral surface (circumferential surface) of the rotating drum DR by a plurality of scanning units Un (U1 to U6). Since the exposure head 14 repeatedly performs pattern exposure for the electronic device on the substrate P, the exposure region (electronic device formation region) W on which the pattern is exposed is in the long direction of the substrate P as shown in FIG. A plurality of them are provided at predetermined intervals along the above. The plurality of scanning units Un (U1 to U6) are arranged in a staggered arrangement in two rows in the transport direction of the substrate P with the central surface Poc interposed therebetween. The odd-numbered scanning units U1, U3, and U5 are arranged in a row on the upstream side (-X direction side) of the substrate P in the transport direction with respect to the central surface Poc and separated by a predetermined interval along the Y direction. Have been placed. The even-numbered scanning units U2, U4, and U6 are arranged in a row on the downstream side (+ X direction side) of the substrate P in the transport direction with respect to the central surface Poc, separated by a predetermined interval along the Y direction. There is. The odd-numbered scanning units U1, U3, and U5 and the even-numbered scanning units U2, U4, and U6 are provided symmetrically with respect to the central plane Poc when viewed in the XZ plane.

Each scanning unit Un (U1 to U6) projects the beam LBn (n = 1 to 6) supplied from the beam distribution unit BDU so as to converge on the spot light SP on the irradiated surface of the substrate P. The spot light SP is scanned one-dimensionally by a rotating polygon mirror PM (see FIG. 4). The polygon mirror PM of each scanning unit Un (U1 to U6) scans the spot light SP one-dimensionally in the Y direction on the irradiated surface of the substrate P. By scanning the spot light SP, a linear drawing line (scanning line) SLn (n = 1, 2, ..., 6) is specified.

The scanning unit U1 scans the spot light SP along the drawing lines SL1, and similarly, the scanning units U2 to U6 scan the spot light SP along the drawing lines SL2 to SL6. As shown in FIGS. 2 and 3, the drawing lines SL1 to SL6 of the plurality of scanning units U1 to U6 are separated into the odd-numbered and even-numbered drawing lines SLn in the sub-scanning direction which is the long direction of the substrate P. However, in the Y direction (the width direction of the substrate P or the main scanning direction), they are set so as to be joined without being separated from each other. In the beam LBn emitted from the beam distribution unit BDU, the beam incident on the scanning unit U1 is represented by LB1, and similarly, the beam LBn incident on the scanning units U2 to U6 is represented by LB2 to LB6. The beam LBn incident on the scanning unit Un may be a linearly polarized light (P-polarized light or S-polarized light) polarized in a predetermined direction, or a circularly polarized beam.

As shown in FIG. 3, the plurality of scanning units U1 to U6 are arranged so as to cover the entire width direction of the exposure region W in total. As a result, each of the scanning units U1 to U6 can draw a pattern for each of a plurality of regions (drawing ranges) divided in the width direction of the substrate P. For example, assuming that the scanning length in the Y direction (the length of the drawing line SLn) by one scanning unit Un is about 20 to 60 mm, the odd-numbered scanning units U1, U3, and U5 and the even-numbered scanning unit U2 By arranging a total of six scanning units Un, including three U4 and U6, in the Y direction, the width in the Y direction that can be drawn is expanded to about 120 to 360 mm. In principle, the lengths of the drawing lines SL1 to SL6 (the length of the drawing range) are the same. That is, in principle, the scanning distances of the spot light SPs of the beams LBn scanned along each of the drawing lines SL1 to SL6 are the same. If the width of the exposure area W (the width of the substrate P) is to be further increased, the length of the drawing line SLn itself can be increased or the number of scanning units Un arranged in the Y direction can be increased. it can.

The actual drawing lines SLn (SL1 to SL6) are set to be slightly shorter than the maximum length (maximum scanning length) at which the spot light SP can actually scan on the irradiated surface. For example, when the drawing magnification in the main scanning direction (Y direction) is the initial value (without magnification correction) and the scanning length of the drawing line SLn capable of drawing a pattern is 30 mm, the maximum scanning of the spot light SP on the irradiated surface The length is set to about 31 mm with a margin of about 0.5 mm on each of the drawing start point (scanning start point) side and the drawing end point (scanning end point) side of the drawing line SLn. By setting in this way, it is possible to finely adjust the position of the drawing line SLn of 30 mm in the main scanning direction and finely adjust the drawing magnification within the range of the maximum scanning length of the spot light SP of 31 mm. Become. The maximum scanning length of the spot light SP is not limited to 31 mm, and is mainly determined by the aperture of the fθ lens FT (see FIG. 4) provided after the polygon mirror (rotating polygon mirror) PM in the scanning unit Un.

The plurality of drawing lines SL1 to SL6 are arranged in a staggered arrangement in two rows in the circumferential direction of the rotating drum DR with the central surface Poc interposed therebetween. The odd-numbered drawing lines SL1, SL3, and SL5 are located on the irradiated surface of the substrate P on the upstream side (−X direction side) of the substrate P in the transport direction with respect to the central surface Poc. The even-numbered drawing lines SL2, SL4, and SL6 are located on the irradiated surface of the substrate P on the downstream side (+ X direction side) of the substrate P in the transport direction with respect to the central surface Poc. The drawing lines SL1 to SL6 are substantially parallel to the width direction of the substrate P, that is, the central axis AXo of the rotating drum DR.

The drawing lines SL1, SL3, and SL5 are arranged in a straight line at predetermined intervals along the width direction (main scanning direction) of the substrate P. Similarly, the drawing lines SL2, SL4, and SL6 are also arranged in a straight line at predetermined intervals along the width direction (main scanning direction) of the substrate P. At this time, the drawing line SL2 is arranged between the drawing line SL1 and the drawing line SL3 in the width direction of the substrate P. Similarly, the drawing line SL3 is arranged between the drawing line SL2 and the drawing line SL4 in the width direction of the substrate P. The drawing line SL4 is arranged between the drawing line SL3 and the drawing line SL5 in the width direction of the substrate P, and the drawing line SL5 is arranged between the drawing line SL4 and the drawing line SL6 in the width direction of the substrate P. Has been done.

The main scanning direction of the spot light SP by each of the beams LB1, LB3, and LB5 scanned along each of the odd-numbered drawing lines SL1, SL3, and SL5 is a one-dimensional direction, which is the same direction. There is. The main scanning direction of the spot light SP by each of the beams LB2, LB4, and LB6 scanned along each of the even-numbered drawing lines SL2, SL4, and SL6 is a one-dimensional direction, which is the same direction. There is. The main scanning direction of the spot light SP of the beams LB1, LB3, LB5 scanned along the drawing lines SL1, SL3, SL5 and the beams LB2, LB4, LB6 scanned along the drawing lines SL2, SL4, SL6. The directions may be opposite to the main scanning direction of the spot light SP. In the first embodiment, the main scanning direction of the spot light SP of the beams LB1, LB3, and LB5 scanned along the drawing lines SL1, SL3, and SL5 is the −Y direction. Further, the main scanning direction of the spot light SP of the beams LB2, LB4, and LB6 scanned along the drawing lines SL2, SL4, and SL6 is the + Y direction. As a result, the ends of the drawing lines SL1, SL3, and SL5 on the drawing start point side and the ends of the drawing lines SL2, SL4, and SL6 on the drawing start point side are adjacent to or partially overlap each other in the Y direction. Further, the end of the drawing lines SL3 and SL5 on the drawing end point side and the end of the drawing lines SL2 and SL4 on the drawing end point side are adjacent to each other or partially overlap in the Y direction. When arranging each drawing line SLn so that the ends of adjacent drawing lines SLn partially overlap each other in the Y direction, for example, the drawing start point or the drawing end is set with respect to the length of each drawing line SLn. It is preferable to overlap the points in the Y direction within a range of several% or less. Note that joining the drawing lines SLn in the Y direction means that the ends of the drawing lines SLn are adjacent to each other or partially overlap with each other in the Y direction. That is, it means that the patterns drawn by each of the two drawing lines SLn adjacent to each other in the Y direction are spliced in the Y direction and exposed.

The width (dimension in the X direction) of the drawing line SLn in the sub-scanning direction is a thickness corresponding to the effective size (diameter) φ of the spot light SP on the substrate P. For example, when the effective size (dimension) φ of the spot light SP is 3 μm, the width of the drawing line SLn is also 3 μm. Further, in the case of the first embodiment, since the beam LB from the light source device LS is pulsed light, the spot light SP projected on the drawing line SLn during the main scan is the oscillation frequency Fa of the beam LB. It becomes discrete according to (for example, 100 MHz). Therefore, it is necessary to overlap the spot light SP projected by the 1-pulse light of the beam LBn from the beam distribution unit BDU and the spot light SP projected by the next 1-pulse light in the main scanning direction. The amount of overlap is set by the size φ of the spot light SP, the scanning speed (main scanning speed) Vs of the spot light SP, and the oscillation frequency Fa of the beam LB. The effective size φ of the spot light SP is determined by 1 / e ² (or 1/2) of the peak intensity of the spot light SP when the intensity distribution of the spot light SP is approximated by a Gaussian distribution.

In the first embodiment, the scanning speed Vs and the oscillation frequency Fa of the spot light SP are set so that the spot light SP overlaps about φ × 1/2 with respect to the effective size (dimension) φ. Will be done. Therefore, the projection interval of the spot light SP along the main scanning direction is φ / 2. Therefore, with respect to the sub-scanning direction (direction orthogonal to the drawing line SLn), the substrate P is effective for the spot light SP between one scanning of the spot light SP along the drawing line SLn and the next scanning. It is desirable to set it so that it moves by a distance of approximately 1/2 of the size φ. Further, the exposure amount to the photosensitive functional layer on the substrate P can be set by adjusting the peak value of the beam LB (pulse light), but the exposure amount is increased in a situation where the intensity of the beam LB cannot be increased. If you want, the spot light SP can be reduced by either a decrease in the scanning speed Vs in the main scanning direction of the spot light SP, an increase in the oscillation frequency Fa of the beam LB, or a decrease in the transport speed Vt in the sub-scanning direction of the substrate P. The amount of overlap in the main scanning direction or the sub scanning direction may be increased. The scanning speed Vs of the spot light SP in the main scanning direction increases in proportion to the rotation speed (rotation speed Vp) of the polygon mirror PM.

Each scanning unit Un (U1 to U6) irradiates each beam LBn toward the substrate P so that each beam LBn travels toward the central axis AXo of the rotating drum DR, at least in the XZ plane. As a result, the optical path (beam central axis) of the beam LBn traveling from each scanning unit Un (U1 to U6) toward the substrate P becomes parallel to the normal line of the irradiated surface of the substrate P in the XZ plane. Further, in each scanning unit Un (U1 to U6), the beam LBn irradiating the drawing lines SLn (SL1 to SL6) is perpendicular to the irradiated surface of the substrate P in a plane parallel to the YZ plane. , The beam LBn is irradiated toward the substrate P. That is, the beams LBn (LB1 to LB6) projected on the substrate P are scanned in a telecentric state with respect to the main scanning direction of the spot light SP on the irradiated surface. Here, a line (also referred to as an optical axis) perpendicular to the irradiated surface of the substrate P through each midpoint of a predetermined drawing line SLn (SL1 to SL6) defined by each scanning unit Un (U1 to U6). Is referred to as an irradiation central axis Le (Le1 to Le6).

Each irradiation central axis Len (Le1 to Le6) is a line connecting the drawing lines SL1 to SL6 and the central axis AXo in the XZ plane. The irradiation center axes Le1, Le3, and Le5 of the odd-numbered scanning units U1, U3, and U5 are in the same direction in the XZ plane, and the irradiation center axes Le2 of the even-numbered scanning units U2, U4, and U6 are respectively. , Le4 and Le6 are in the same direction in the XZ plane. Further, the irradiation central axes Le1, Le3, Le5 and the irradiation central axes Le2, Le4, Le6 are set so that the angle with respect to the central surface Poc is ± θ1 in the XZ plane (see FIG. 1).

The plurality of alignment microscopes AM1m (AM11 to AM14) and AM2m (AM21 to AM24) shown in FIG. 1 detect a plurality of alignment marks (marks) MKm (MK1 to MK4) formed on the substrate P shown in FIG. This is for the purpose, and a plurality of (four in the first embodiment) are provided along the Y direction. The plurality of alignment marks MKm (MK1 to MK4) are reference marks for relatively aligning (aligning) a predetermined pattern drawn in the exposed area W on the irradiated surface of the substrate P with the substrate P. Is. The plurality of alignment microscopes AM1m (AM11 to AM14) and AM2m (AM21 to AM24) have a plurality of alignment marks MKm (MK1 to MK4) on the substrate P supported by the outer peripheral surface (circumferential surface) of the rotating drum DR. Is detected. The plurality of alignment microscopes AM1m (AM11 to AM14) are larger than the irradiated area (the area surrounded by the drawing lines SL1 to SL6) on the substrate P by the spot light SP of the beam LBn (LB1 to LB6) from the exposure head 14. It is provided on the upstream side (−X direction side) of the substrate P in the transport direction. Further, the plurality of alignment microscopes AM2m (AM21 to AM24) are from the irradiated area (the area surrounded by the drawing lines SL1 to SL6) on the substrate P by the spot light SP of the beam LBn (LB1 to LB6) from the exposure head 14. Is also provided on the downstream side (+ X direction side) of the substrate P in the transport direction.

The alignment microscopes AM1m (AM11 to AM14) and AM2m (AM21 to AM24) are a local region (observation region) Vw1m (Vw11) including a light source that projects illumination light for alignment onto the substrate P and an alignment mark MKm on the surface of the substrate P. ~ Vw14), an observation optical system (including an objective lens) that obtains a magnified image of Vw2m (Vw21 to Vw24), and while the substrate P is moving in the transport direction, the transport speed Vt of the substrate P is increased. It has an image pickup device such as a CCD or CMOS that takes an image with a corresponding high-speed shutter. The imaging signals (image data) captured by each of the plurality of alignment microscopes AM1m (AM11 to AM14) and AM2m (AM21 to AM24) are sent to the control device 16. The control device 16 is provided with a mark position detecting unit, and detects the position (mark position information) of the alignment marks MKm (MK1 to MK4) on the substrate P by performing image analysis of a plurality of imaging signals. The illumination light for alignment is light in a wavelength range that has almost no sensitivity to the photosensitive functional layer on the substrate P, for example, light having a wavelength of about 500 to 800 nm.

A plurality of alignment marks MK1 to MK4 are provided around each exposure region W. A plurality of alignment marks MK1 and MK4 are formed on both sides of the exposure region W in the width direction of the substrate P at regular intervals Dh along the longitudinal direction of the substrate P. The alignment mark MK1 is formed on the −Y direction side in the width direction of the substrate P, and the alignment mark MK4 is formed on the + Y direction side in the width direction of the substrate P. Such alignment marks MK1 and MK4 are positioned at the same position in the longitudinal direction (X direction) of the substrate P when the substrate P is not deformed due to a large tension or a thermal process. Be placed. Further, the alignment marks MK2 and MK3 are located between the alignment mark MK1 and the alignment mark MK4, along the width direction (short direction) of the substrate P in the margins between the + X direction side and the −X direction side of the exposure region W. Is formed. The alignment marks MK2 and MK3 are formed between the exposure region W and the exposure region W. The alignment mark MK2 is formed on the −Y direction side in the width direction of the substrate P, and the alignment mark MK3 is formed on the + Y direction side of the substrate P.

Further, the distance between the alignment mark MK1 arranged at the end on the −Y direction side of the substrate P and the alignment mark MK2 in the margin portion in the Y direction, the distance between the alignment mark MK2 in the margin portion and the alignment mark MK3 in the Y direction, and The distance between the alignment mark MK4 arranged at the end on the + Y direction side of the substrate P and the alignment mark MK3 in the margin portion in the Y direction is set to the same distance. These alignment marks MKm (MK1 to MK4) may be formed together with the formation of the pattern layer of the first layer. For example, when the pattern of the first layer is exposed, the pattern for the alignment mark may also be exposed around the exposure region W where the pattern is exposed. The alignment mark MKm may be formed in the exposure region W. For example, it may be formed in the exposure region W and along the contour of the exposure region W. Further, a pattern portion at a specific position or a portion having a specific shape in the pattern of the electronic device formed in the exposure region W may be used as the alignment mark MKm.

As shown in FIG. 3, the alignment microscopes AM11 and AM21 are arranged so as to image the alignment mark MK1 existing in the observation region (detection region) Vw11 and Vw21 by the objective lens. Similarly, the alignment microscopes AM12 to AM14 and AM22 to AM24 are arranged so as to image the alignment marks MK2 to MK4 existing in the observation regions Vw12 to Vw14 and Vw22 to Vw24 by the objective lens. Therefore, the plurality of alignment microscopes AM11 to AM14 and AM21 to AM24 correspond to the positions of the plurality of alignment marks MK1 to MK4, and the substrate P is in the order of AM11 to AM14 and AM21 to AM24 from the −Y direction side of the substrate P. It is provided along the width direction of. In FIG. 2, the observation region Vw2m (Vw21 to Vw24) of the alignment microscope AM2m (AM21 to AM24) is not shown.

In the plurality of alignment microscopes AM1m (AM11 to AM14), the distance between the exposure position (drawing lines SL1 to SL6) and the observation area Vw1m (Vw11 to Vw14) in the X direction is the distance in the long direction of the exposure area W in the X direction. It is provided so that it is shorter than the length. Similarly, in the plurality of alignment microscopes AM2m (AM21 to AM24), the distance between the exposure position (drawing lines SL1 to SL6) and the observation area Vw2m (Vw21 to Vw24) in the X direction is the X of the exposure area W. It is provided so as to be shorter than the length in the direction. The number of alignment microscopes AM1m and AM2m provided in the Y direction can be changed according to the arrangement and number of alignment marks MKm formed in the width direction of the substrate P. Further, the size of the substrate P of each observation area Vw1m (Vw11 to Vw14) and Vw2m (Vw21 to Vw24) on the irradiated surface is set according to the size of the alignment marks MK1 to MK4 and the alignment accuracy (position measurement accuracy). However, the size is about 100 to 500 μm square.

As shown in FIG. 2, both ends of the rotary drum DR are provided with scale portions SDa and SDb having scales formed in an annular shape over the entire peripheral surface of the rotary drum DR in the circumferential direction. The scale portions SDa and SDb are diffraction gratings in which concave or convex grid lines (scales) are engraved at a constant pitch (for example, 20 μm) in the circumferential direction of the outer peripheral surface of the rotating drum DR, and are incremental scales. It is configured as. The scale portions SDa and SDb rotate integrally with the rotating drum DR around the central axis AXo. A plurality of encoder heads (hereinafter, also simply referred to as encoders) ENja and ENjb (note that j = 1, 2, 3, 4) as scale reading heads for reading the scale units SDa and SDb face the scale units SDa and SDb. (See FIGS. 1 and 2). In FIG. 2, the encoders EN4a and EN4b are not shown.

The encoders ENja and ENjb optically detect the rotation angle position of the rotary drum DR. Four encoders ENja (EN1a, EN2a, EN3a, EN4a) are provided so as to face the scale portion SDa provided at the end on the −Y direction side of the rotating drum DR. Similarly, four encoders ENjb (EN1b, EN2b, EN3b, EN4b) are provided so as to face the scale portion SDb provided at the end on the + Y direction side of the rotary drum DR.

The encoders EN1a and EN1b are provided on the upstream side (-X direction side) of the substrate P in the transport direction with respect to the central surface Poc, and are arranged on the installation azimuth line Lx1 (see FIGS. 1 and 2). .. The installation azimuth line Lx1 is a line connecting the projection positions (reading positions) of the optical beams for measurement of the encoders EN1a and EN1b on the scale portions SDa and SDb on the XZ plane and the central axis AXo. Further, the installation azimuth line Lx1 is a line connecting the observation region Vw1m (Vw11 to Vw14) of each alignment microscope AM1m (AM11 to AM14) and the central axis AXo in the XZ plane. That is, a plurality of alignment microscopes AM1m (AM11 to AM14) are also arranged on the installation directional line Lx1.

The encoders EN2a and EN2b are provided on the upstream side (-X direction side) of the substrate P in the transport direction with respect to the central surface Poc, and are downstream of the encoders EN1a and EN1b in the transport direction of the substrate P (+ X direction). It is provided on the side). The encoders EN2a and EN2b are arranged on the installation direction line Lx2 (see FIGS. 1 and 2). The installation azimuth line Lx2 is a line connecting the projection positions (reading positions) of the optical beams for measurement of the encoders EN2a and EN2b on the scale portions SDa and SDb on the XZ plane and the central axis AXo. The installation azimuth line Lx2 overlaps with the irradiation center axes Le1, Le3, and Le5 at the same angle position on the XZ plane.

The encoders EN3a and EN3b are provided on the downstream side (+ X direction side) of the substrate P in the transport direction with respect to the central surface Poc, and are arranged on the installation azimuth line Lx3 (see FIGS. 1 and 2). The installation azimuth line Lx3 is a line connecting the projection positions (reading positions) of the optical beams for measurement of the encoders EN3a and EN3b on the scale portions SDa and SDb on the XZ plane and the central axis AXo. The installation azimuth line Lx3 overlaps with the irradiation center axes Le2, Le4, and Le6 at the same angle position on the XZ plane. Therefore, the installation directional line Lx2 and the installation directional line Lx3 are set so that the angle with respect to the central surface Poc is ± θ1 in the XZ plane (see FIG. 1).

The encoders EN4a and EN4b are provided on the downstream side (+ X direction side) of the substrate P in the transport direction from the encoders EN3a and EN3b, and are arranged on the installation azimuth line Lx4 (see FIG. 1). The installation azimuth line Lx4 is a line connecting the projection positions (reading positions) of the optical beams for measurement of the encoders EN4a and EN4b on the scale portions SDa and SDb on the XZ plane and the central axis AXo. Further, the installation directional line Lx4 is a line connecting the observation region Vw2m (Vw21 to Vw24) of each alignment microscope AM2m (AM21 to AM24) and the central axis AXo in the XZ plane. That is, a plurality of alignment microscopes AM2m (AM21 to AM24) are also arranged on the installation directional line Lx4. The installation directional line Lx1 and the installation directional line Lx4 are set so that the angle with respect to the central surface Poc is ± θ2 in the XZ plane.

The encoders ENja (EN1a to EN4a) and ENjb (EN1b to EN4b) project an optical beam for measurement toward the scale units SDa and SDb, and the reflected light flux (diffracted light) is photoelectrically detected as a detection signal (two phases). The signal) is output to the control device 16. The detection signal (two-phase signal) for each encoder is inserted into the control device 16 to digitally count the amount of movement of the grids of the scale units SDa and SDb, thereby changing the rotation angle position and angle of the rotating drum DR. Alternatively, a plurality of counter circuits are provided to measure the amount of movement of the substrate P with a submicron resolution (a resolution of a fraction or less of the pixel size on the substrate P set by design). From the change in the angle of the rotating drum DR, the transport speed Vt of the substrate P can also be measured. The position of the alignment mark MKm (MK1 to MK4) and the exposure area on the substrate P based on the count value (digital count value) of the counter circuit corresponding to each of the encoders ENja (EN1a to EN4a) and ENjb (EN1b to EN4b). The positional relationship between W and each drawing line SLn in the sub-scanning direction can be specified. In addition, the address position (access address) related to the sub-scanning direction of the memory unit that stores the drawing data (for example, bitmap data) of the pattern to be drawn on the substrate P based on the count value (digital count value) of the counter circuit. Is also specified. As shown in FIG. 2, a Z-phase mark ZZ indicating the origin position in the circumferential direction is formed at one position in the circumferential direction of the scale portion SDa (SDb), and the encoders ENja (EN1a to EN4a) and ENjb (EN1b to When each of the EN4b) detects the Z-phase mark ZZ, the count value of the corresponding counter circuit is instantly reset to zero (or a constant value), and then the movement amount of the grid of the scale unit SDa (SDb) is changed. Continue to measure.

Next, the optical configuration of the scanning units Un (U1 to U6) will be described with reference to FIG. Since each scanning unit Un (U1 to U6) has the same configuration, only the scanning unit U1 will be described as a representative, and the description of the other scanning units Un will be omitted. Further, in FIG. 4, the direction parallel to the irradiation central axis Len (Le1) is the Zt direction, and the substrate P is on a plane orthogonal to the Zt direction, and the substrate P is transferred from the processing device PR1 to the processing device PR2 via the exposure device EX. The direction of the head is the Xt direction, and the direction on the plane orthogonal to the Zt direction and orthogonal to the Xt direction is the Yt direction. That is, the three-dimensional coordinates of Xt, Yt, and Zt in FIG. 4 are the three-dimensional coordinates of X, Y, and Z in FIG. 1, and the Z-axis direction is parallel to the irradiation central axis Len (Le1) about the Y-axis. It becomes the three-dimensional coordinates rotated in this way.

As shown in FIG. 4, in the scanning unit U1, the reflection mirror M10, the beam expander BE, the reflection mirror M11, along the traveling direction of the beam LB1 from the incident position of the beam LB1 to the irradiated surface (substrate P), Polarized beam splitter BS1, Reflective mirror M12, Shift optical member (parallel plate) SR, Deflection adjustment optical member (Prism) DP, Field aperture FA, Reflective mirror M13, λ / 4 wavelength plate QW, Cylindrical lens CYa, Reflective mirror M14, A polygon mirror PM, an fθ lens FT, a reflection mirror M15, and a cylindrical lens CYb are provided. Further, in the scanning unit U1, an origin sensor (origin detector, detection sensor) OP1 for detecting the drawing start start timing of the scanning unit U1 and a polarizing beam splitter BS1 for reflecting light from the irradiated surface (board P) are provided. An optical lens system G10 and a photodetector DT for detecting through the light are provided.

The beam LB1 incident on the scanning unit U1 travels in the −Zt direction and is incident on the reflection mirror M10 tilted by 45 ° with respect to the XtYt plane. The axis of the beam LB1 incident on the scanning unit U1 is incident on the reflection mirror M10 so as to be coaxial with the irradiation center axis Le1. The reflection mirror M10 directs the incident beam LB1 in the -Xt direction toward the reflection mirror M11 away from the reflection mirror M10 in the -Xt direction along the optical axis AXa of the beam expander BE set parallel to the Xt axis. reflect. Therefore, the optical axis AXa is orthogonal to the irradiation center axis Le1 in a plane parallel to the XtZt plane. The beam expander BE has a condenser lens Be1 and a collimated lens Be2 that makes the beam LB1 diverged after being converged by the condenser lens Be1 into parallel light, and expands the diameter of the beam LB1.

The reflection mirror M11 is arranged at an angle of 45 ° with respect to the YtZt plane, and reflects the incident beam LB1 (optical axis AXa) toward the polarizing beam splitter BS1 in the −Yt direction. The polarization separation plane of the polarization beam splitter BS1 installed apart from the reflection mirror M11 in the −Yt direction is arranged at an angle of 45 ° with respect to the YtZt plane, reflects the P-polarized beam, and is orthogonal to the P-polarized light. It transmits a beam of linearly polarized light (S-polarized light) polarized in the direction of polarization. Since the beam LB1 incident on the scanning unit U1 is a P-polarized beam here, the polarizing beam splitter BS1 reflects the beam LB1 from the reflection mirror M11 in the −Xt direction and guides it toward the reflection mirror M12.

The reflection mirror M12 is arranged at an angle of 45 ° with respect to the XtYt plane, and reflects the incident beam LB1 in the −Zt direction toward the reflection mirror M13 away from the reflection mirror M12 in the −Zt direction. The beam LB1 reflected by the reflection mirror M12 is a shift optical member SR composed of two quartz parallel flat plates Sr1 and Sr2 along the optical axis AXc parallel to the Zt axis, and two wedge-shaped prisms Dp1 and Dp2. It passes through the deflection adjusting optical member DP composed of the above and the field aperture (field aperture) FA, and is incident on the reflection mirror M13. By tilting each of the parallel flat plates Sr1 and Sr2, the shift optical member SR two-dimensionally positions the center position in the cross section of the beam LB1 in a plane (XtYt plane) orthogonal to the traveling direction (optical axis AXc) of the beam LB1. To adjust. The deflection adjusting optical member DP parallels the axis of the beam LB1 and the optical axis AXc by rotating each of the prisms Dp1 and Dp2 around the optical axis AXc, or the beam LB1 reaching the irradiated surface of the substrate P. It is possible to parallelize the axis of No. 1 with the irradiation center axis Le1.

The reflection mirror M13 is arranged at an angle of 45 ° with respect to the XtYt plane, and reflects the incident beam LB1 toward the reflection mirror M14 in the + Xt direction. The beam LB1 reflected by the reflection mirror M13 is incident on the reflection mirror M14 via the λ / 4 wave plate QW and the cylindrical lens CYa. The reflection mirror M14 reflects the incident beam LB1 toward the polygon mirror (rotating multifaceted mirror, scanning deflection member) PM. The polygon mirror PM reflects the incident beam LB1 toward the fθ lens FT having the optical axis AXf parallel to the Xt axis in the + Xt direction. The polygon mirror PM deflects (reflects) the incident beam LB1 one-dimensionally in a plane parallel to the XtYt plane in order to scan the spot light SP of the beam LB1 on the irradiated surface of the substrate P. Specifically, the polygon mirror PM has a rotation axis AXp extending in the Zt axis direction and a plurality of reflection surface RPs formed around the rotation axis AXp (in the present embodiment, the number Np of the reflection surface RPs is 8). ) And. By rotating this polygon mirror PM around the rotation axis AXp in a predetermined rotation direction, the reflection angle of the pulsed beam LB1 irradiated on the reflection surface RP can be continuously changed. As a result, the reflection direction of the beam LB1 is deflected by one reflecting surface RP, and the spot light SP of the beam LB1 irradiated on the irradiated surface of the substrate P is directed in the main scanning direction (width direction of the substrate P, Yt direction). It can be scanned along.

That is, the spot light SP of the beam LB1 can be scanned once along the main scanning direction by one reflecting surface RP of the polygon mirror PM. Therefore, the number of drawing lines SL1 in which the spot light SP is scanned on the irradiated surface of the substrate P by one rotation of the polygon mirror PM is eight, which is the same as the number of reflecting surface RPs at the maximum. The polygon mirror PM is rotated at a constant speed by a rotation drive source (for example, a motor, a reduction mechanism, etc.) RM under the control of the control device 16. As described above, the effective length of the drawing line SL1 (for example, 30 mm) is set to a length equal to or less than the maximum scanning length (for example, 31 mm) at which the spot light SP can be scanned by the polygon mirror PM. In the initial setting (design), the center point of the drawing line SL1 (the point through which the irradiation center axis Le1 passes) is set at the center of the maximum scanning length.

The cylindrical lens CYa converges the incident beam LB1 on the reflection surface RP of the polygon mirror PM in the non-scanning direction (Zt direction) orthogonal to the main scanning direction (rotation direction) of the polygon mirror PM. That is, the cylindrical lens CYa converges the beam LB1 in a slit shape (oblong shape) extending in a direction parallel to the XtYt plane on the reflection surface RP. When the reflective surface RP is tilted with respect to the Zt direction due to the cylindrical lens CYa whose bus is parallel to the Yt direction and the cylindrical lens CYb described later (the tilt of the reflective surface RP with respect to the normal of the XtYt plane). Even if there is, the influence can be suppressed. For example, it is possible to prevent the irradiation position of the beam LB1 (drawing line SL1) irradiated on the irradiated surface of the substrate P from shifting in the Xt direction due to a slight tilt error for each reflecting surface RP of the polygon mirror PM. it can.

The fθ lens FT having an optical axis AXf extending in the Xt axis direction is a telecentric scan lens that projects the beam LB1 reflected by the polygon mirror PM onto the reflection mirror M15 so as to be parallel to the optical axis AXf in the XtYt plane. Is. The angle of incidence θ of the beam LB1 on the fθ lens FT changes according to the rotation angle (θ / 2) of the polygon mirror PM. The fθ lens FT projects the beam LB1 at an image height position on the irradiated surface of the substrate P in proportion to its incident angle θ via the reflection mirror M15 and the cylindrical lens CYb. Assuming that the focal length is fo and the image height position is y, the fθ lens FT is designed to satisfy the relationship of y = fo × θ (distortion). Therefore, the fθ lens FT makes it possible to accurately scan the beam LB1 in the Yt direction (Y direction) at a constant velocity. When the angle of incidence θ on the fθ lens FT is 0 degrees, the beam LB1 incident on the fθ lens FT travels along the optical axis AXf.

The reflection mirror M15 reflects the beam LB1 from the fθ lens FT toward the substrate P via the cylindrical lens CYb in the −Zt direction. The beam LB1 projected on the substrate P by the fθ lens FT and the cylindrical lens CYb whose generatrix is parallel to the Yt direction is a minute spot light having a diameter of about several μm (for example, 3 μm) on the irradiated surface of the substrate P. Converged in SP. Further, the spot light SP projected on the irradiated surface of the substrate P is one-dimensionally scanned by the polygon mirror PM by the drawing line SL1 extending in the Yt direction. The optical axis AXf of the fθ lens FT and the irradiation center axis Le1 are on the same plane, and the plane is parallel to the XtZt plane. Therefore, the beam LB1 traveling on the optical axis AXf is reflected by the reflection mirror M15 in the −Zt direction, and is projected onto the substrate P coaxially with the irradiation center axis Le1. In the first embodiment, at least the fθ lens FT functions as a projection optical system that projects the beam LB1 deflected by the polygon mirror PM onto the irradiated surface of the substrate P. Further, at least the reflection members (reflection mirrors M11 to M15) and the polarization beam splitter BS1 function as optical path deflecting members that bend the optical path of the beam LB1 from the reflection mirror M10 to the substrate P. By this optical path deflection member, the incident axis of the beam LB1 incident on the reflection mirror M10 and the irradiation center axis Le1 can be made substantially coaxial. With respect to the XtZt plane, the beam LB1 passing through the scanning unit U1 passes through an optical path bent in a crank shape, and then travels in the −Zt direction and is projected onto the substrate P.

In this way, with the substrate P being conveyed in the sub-scanning direction, each scanning unit Un (U1 to U6) primary the spot light SP of the beam LBn (LB1 to LB6) in the main scanning direction (Y direction). By scanning originally, the spot light SP can be relatively two-dimensionally scanned on the irradiated surface of the substrate P.

As an example, the effective length (drawing length) of each drawing line SL1 to SL6 is set to 30 mm, and the effective size φ is 1/2 of the spot light SP having a diameter of 3 μm, that is, 1.5 (= 3). When the spot light SP is irradiated onto the irradiated surface of the substrate P along the drawing lines SLn (SL1 to SL6) while overlapping by × 1/2) μm, the pulsed spot light SP is 1.5 μm. It is irradiated at intervals of. Therefore, the number of spot light SPs irradiated in one scan is 20000 (= 30 [mm] /1.5 [μm]). Further, assuming that the feed rate (conveyance speed) Vt in the sub-scanning direction of the substrate P is 2.42 mm / sec and the spot light SP is scanned in the sub-scanning direction at intervals of 1.5 μm, the drawing line 1 scan start along SLn (drawing start) point and the time difference between the next scan starting point (period) Tpx is about 620μsec (= 1.5 [μm] / 2.42 [mm / sec]) and Become. This time difference Tpx is the time for the polygon mirror PM of the 8-reflecting surface RP to rotate by one surface (45 degrees = 360 degrees / 8). In this case, since the time for one rotation of the polygon mirror PM needs to be set to about 4.96 msec (= 8 × 620 [μsec]), the rotation speed Vp of the polygon mirror PM is about 201 per second. It is set to .613 rpm (= 1 / 4.96 [msec]), that is, about 12096.88 rpm.

On the other hand, the maximum incident angle (corresponding to the maximum scanning length of the spot light SP) that the beam LB1 reflected by the 1 reflecting surface RP of the polygon mirror PM effectively enters the fθ lens FT is the focal length and the maximum scanning length of the fθ lens FT. It is roughly decided by. As an example, in the case of a polygon mirror PM having eight reflecting surface RPs, the ratio (scanning efficiency) of the rotation angle α that contributes to actual scanning among the rotation angles of 45 degrees for one reflecting surface RP is α / 45 degrees. expressed. In the first embodiment, since the rotation angle α that contributes to the actual scanning is set to a range larger than 10 degrees and smaller than 15 degrees, the scanning efficiency is 1/3 (= 15 degrees / 45 degrees), and fθ. The maximum incident angle of the lens FT is 30 degrees (± 15 degrees about the optical axis AXf). Therefore, the time Ts required to scan the spot light SP by the maximum scanning length (for example, 31 mm) of the drawing line SLn is Ts = Tpx × scanning efficiency, and in the case of the above numerical example, the time Ts, Approximately 206.666 ... μsec (= 620 [μsec] / 3). Since the effective scanning length of the drawing lines SLn (SL1 to SL6) in the first embodiment is 30 mm, the scanning time Tsp of one scan of the spot light SP along the drawing line SLn is about 200 μsec ( = 206.666 ... [μsec] x 30 [mm] / 31 [mm]). Therefore, since it is necessary to irradiate 20000 spot light SP (pulse light) during this time Tsp, the emission frequency (oscillation frequency) Fa of the beam LB from the light source device LS is Fa ≈ 20000 times / 200 μsec≈ It will be 100 MHz.

The origin sensor OP1 shown in FIG. 4 generates the origin signal SZ1 when the rotation position of the reflection surface RP of the polygon mirror PM reaches a predetermined position where scanning of the spot light SP by the reflection surface RP can be started. In other words, the origin sensor OP1 generates the origin signal SZ1 when the angle of the reflecting surface RP that scans the spot light SP is set to a predetermined angle position. Since the polygon mirror PM has eight reflecting surface RPs, the origin sensor OP1 outputs the origin signal SZ1 eight times during the period in which the polygon mirror PM makes one rotation. The origin signal SZ1 generated by the origin sensor OP1 is sent to the control device 16. After the origin sensor OP1 generates the origin signal SZ1, the scanning along the drawing line SL1 of the spot light SP is started after the delay time Td1 elapses. That is, the origin signal SZ1 is information indicating the drawing start timing (scanning start timing) of the spot light SP by the scanning unit U1. The origin sensor OP1 includes a beam transmission system opa that emits a laser beam Bga in a wavelength range that is not photosensitive with respect to the photosensitive functional layer of the substrate P to the reflecting surface RP, and a laser beam Bga reflected by the reflecting surface RP. It has a beam light receiving system opb that receives the reflected beam Bgb of the above and generates the origin signal SZ1.

The origin sensors OPn provided in the scanning units U2 to U6 are represented by OP2 to OP6, and the origin signal SZn generated by the origin sensors OP2 to OP6 is represented by SZ2 to SZ6. The control device 16 manages which scanning unit Un will scan the spot light SP from now on based on these origin signals SZn (SZ1 to SZ6). Further, the delay time Tdn from the generation of the origin signals SZ2 to SZ6 to the start of scanning of the spot light SP along the drawing lines SL2 to SL6 by the scanning units U2 to U6 may be represented by Td2 to Td6. In the present embodiment, the origin signals SZ1 to SZ6 are used to synchronize the rotation speed of the polygon mirror PMs of the scanning units U1 to U6 to a predetermined value, and the rotation angle position (angle phase) of each polygon mirror PM. Is performed with synchronous control to maintain a predetermined relationship.

The photodetector DT shown in FIG. 4 is, for example, a reflected light generated when a reference pattern formed on the surface of the rotating drum DR or a reference pattern formed at a specific position on the substrate P is scanned by the spot light SP. It has a photoelectric conversion element that photoelectrically converts the change in. When the spot light SP of the beam LB1 is irradiated from the scanning unit U1 to the region where the reference pattern of the rotating drum DR (or the reference pattern on the substrate P) is formed, the reflected light is reflected because the fθ lens FT is a telecentric system. However, the cylindrical lens CYb, the reflection mirror M15, the fθ lens FT, the polygon mirror PM, the reflection mirror M14, the cylindrical lens CYa, the λ / 4 wavelength plate QW, the reflection mirror M13, the field aperture FA, the deflection adjustment optical member DP, and the shift optical member. It passes through the SR and the reflection mirror M12 and returns to the polarized beam splitter BS1. By the action of the λ / 4 wave plate QW, the beam LB1 irradiated to the substrate P is converted from the P-polarized light to the circularly polarized beam LB1, reflected on the surface of the rotating drum DR (or the surface of the substrate P), and polarized. The reflected light returning to the beam splitter BS1 is converted from circularly polarized light to S-polarized light by the λ / 4 wave plate QW, passes through the polarized beam splitter BS1, and reaches the optical detector DT via the optical lens system G10. The scanning unit Un can be calibrated by the position information of the reference pattern with respect to the drawing line SLn measured based on the detection signal from the photodetector DT.

FIG. 5 is a view of the configuration inside the beam distribution unit BDU in the XY plane. The beam distribution unit BDU includes a plurality of drawing optical elements AOMn (AOM1 to AOM6), a plurality of beam splitters BSa to BSe, a plurality of reflection mirrors MR1 to MR5, and a plurality of reflection mirrors FM1 to FM6 for epi-illumination. Have. The drawing optical elements AOMn (AOM1 to AOM6) are arranged in each of the optical paths in which the beam LB from the light source device LS is divided into six, and the first-order diffracted light obtained by diffracting the incident beam in response to a high-frequency drive signal is emitted. , Acousto-Optic Modulator (AOM) that emits as a beam LBn (LB1 to LB6). The diffraction direction of the primary diffracted light (beams LB1 to LB6) in each of the drawing optical elements AOMn (AOM1 to AOM6) is the −Z direction in the plane parallel to the XZ plane, and each drawing optical element AOMn is in the ON state ( The beams LBn (LB1 to LB6) emitted from each drawing optical element AOMn in the state of generating the primary diffracted light are the reflection mirrors FM1 to FM6 for epi-illumination whose reflecting surface is inclined with respect to the XY surface. Is reflected in the −Z direction toward the corresponding scanning units U1 to U6 (reflection mirror M10).

The beam LB from the light source device LS is split into two by the beam splitter BSa, and the beam transmitted through the beam splitter BSa is reflected by the reflection mirrors MR1 and MR2 and then split into two by the beam splitter BSb. The beam reflected by the beam splitter BSb is incident on the drawing optical element AOM5. The beam transmitted through the beam splitter BSb is split into two by the beam splitter BSc, and the beam reflected by the beam splitter BSc is incident on the drawing optical element AOM3. The beam transmitted through the beam splitter BSc is reflected by the reflection mirror MR3 and incident on the drawing optical element AOM1. Similarly, the beam reflected by the beam splitter BSa is reflected by the reflection mirror MR4 and then split into two by the beam splitter BSd. The beam reflected by the beam splitter BSd is incident on the drawing optical element AOM6. The beam transmitted through the beam splitter BSd is split into two by the beam splitter BSe, and the beam reflected by the beam splitter BSe is incident on the drawing optical element AOM4. The beam transmitted through the beam splitter BSe is reflected by the reflection mirror MR5 and is incident on the drawing optical element AOM2.

As described above, the beam LB from the light source device LS is incident on each of the six drawing optical elements AOMn (AOM1 to AOM6) in a state of amplitude division (intensity division) of about 1/6. By turning on / off the application of a high-frequency drive signal to each of the drawing optical elements AOMn (AOM1 to AOM6) according to the bit data of each pixel of the drawing data, each of the scanning units Un (U1 to U6). The intensity of the spot light SP scanned along the drawing line SLn of is modulated. As a result, the pattern corresponding to the drawing data (bitmap) is simultaneously drawn on the substrate P by each scanning unit Un (U1 to U6). The drawing data (pattern data) is provided for each scanning unit Un, and the pattern drawn by the scanning unit Un is divided by pixels having dimensions set according to the size φ of the spot light SP, and each of the plurality of pixels is divided. Is represented by 1-bit logical information (bit data, pixel data) according to the pattern. That is, the drawing data has the row direction as the direction along the scanning direction (main scanning direction, Y direction) of the spot light SP, and the column direction as the direction along the transport direction (secondary scanning direction, X direction) of the substrate P. It is bitmap data composed of logical information (pixel data) of a plurality of pixels decomposed into two dimensions so as to be performed.

The logical information of the pixels for one column of the drawing data corresponds to one drawing line SLn (SL1 to SL6). Therefore, the number of pixels for one row is determined according to the pixel size Pxy on the irradiated surface of the substrate P and the length of the drawing line SLn. The dimension Pxy of this one pixel is set to be equal to or larger than the size φ of the spot light SP. For example, when the effective size φ of the spot light SP is 3 μm, the dimension Pxy of one pixel is set. It is set to about 3 μm square or more. The intensity of the spot light SP projected on the substrate P along one drawing line SLn (SL1 to SL6) is modulated according to the logical information of the pixels for one row. The logical information (bit data) of the pixels for one column is called a pixel data string DLn. That is, the drawing data is bitmap data in which the pixel data strings DLn are arranged in the column direction. The pixel data string DLn of the drawing data of the scanning unit U1 is represented by DL1, and similarly, the pixel data string DLn of the drawing data of the scanning units U2 to U6 is represented by DL2 to DL6. When the bit data of the pixel is "1", it means that the intensity of the spot light SP projected on the substrate P becomes a high level, that is, the drawing optical element AOMn generates the first-order diffracted light. Further, when it is "0", it means that the intensity of the spot light SP projected on the substrate P becomes a low level (for example, zero), that is, the drawing optical element AOMn does not generate the first-order diffracted light.

FIG. 6 is a block diagram showing a main configuration of the control device 16 shown in FIG. 1. The control device 16 is a drawing control unit 100 that controls the entire drawing operation, and the origins of the scanning units U1 to U6. The origin signals SZ1 to SZ6 from the beam light receiving system opb of the sensor OPn are input, and images are taken by the polygon mirror drive unit 102 that controls the motor RM for rotating the polygon mirror PM, and each of the plurality of alignment microscopes AM1m and AM2m. Scale based on the alignment unit 104 that analyzes the images of the alignment marks MK1 to MK4 and generates the mark position information, and the detection signals (two-phase signals) from each of the plurality of encoders EN1a to EN4a and EN1b to EN4b. An encoder counter unit 106 that digitally counts the amount and position of movement of the parts SDa and SDb in the circumferential direction and is reset to zero by the Z-phase mark ZZ for each rotation of the scale parts SDa and SDb (or rotating drum DR). A drawing data storage unit 108 that stores drawing data of a pattern to be drawn by each of the scanning units U1 to U6 in a bitmap format, and a drawing data string (bit stream) for each drawing line SL1 to SL6 read from the drawing data storage unit 108. It includes an AOM drive unit 110 that modulates the drawing optical elements AOM1 to AOM6 corresponding to each of the scanning units U1 to U6 according to the signal), and a drive control unit 112 that controls the rotation drive motor of the rotary drum DR. .. Further, the drawing control unit 100 sends information TMg and CMg for correcting the drawing magnification to the light source device LS, and at the timing when each of the scanning units U1 to U6 scans the substrate P with the spot light SP, the light source device LS Generates a drawing switch signal SHT that controls the beam LB to be emitted by monitoring the generation status of the light source signals SZ1 to SZ6.

In the present embodiment, the beam LB of the light source device LS is pulsed light having an oscillation frequency Fa (for example, 100 MHz), and for that purpose, the light source device LS generates a clock signal LTC having an oscillation frequency Fa. One clock pulse of the clock signal LTC corresponds to one pulse emission of the beam LB. Further, the light source device LS includes a local magnification correction unit that partially fine-tunes the period of the clock signal LTC at a specific pixel position while the spot light SP is being scanned along the drawing line SLn. The clock signal LTC is also used to manage the rotation speed of the polygon mirror PM by the polygon mirror driving unit 102. Further, the light source device LS shifts the pixel data string DLn transmitted by the drawing data storage unit (data storage unit) 108 to the AOM drive unit 110 during one scan of the spot light SP for each pixel bit data. Pixel shift signal (pixel shift pulse) BSC is generated.

FIG. 7 is a diagram showing a specific configuration of a light source device (pulse light source device, pulse laser device) LS. The light source device LS as a fiber laser device includes a pulse light generating unit 20 and a control circuit 22. The pulsed light generating unit 20 includes DFB semiconductor laser elements 30 and 32, a polarizing beam splitter 34, an electro-optical element (intensity modulation unit) 36 as an optical modulator for drawing, a drive circuit 36a of the electro-optical element 36, and a polarizing beam splitter. It has 38, an absorber 40, an excitation light source 42, a combiner 44, a fiber optical amplifier 46, wavelength conversion optical elements 48 and 50, and a plurality of lens elements GL. The control circuit 22 has a signal generation unit 22a that generates a clock signal LTC and a pixel shift pulse BSC.

The DFB semiconductor laser element (first solid-state laser element) 30 responds to the clock signal LTC and has a sharp or sharp pulse-shaped seed light (pulse beam, beam) at an oscillation frequency Fa (for example, 100 MHz) which is a predetermined frequency. ) S1 is generated, and the DFB semiconductor laser element (second solid-state laser element) 32 responds to the clock signal LTC and has a slow (temporally broad) pulse at an oscillation frequency Fa (for example, 100 MHz) which is a predetermined frequency. A seed light (pulse beam, beam) S2 is generated. The light emission timings of the seed light S1 generated by the DFB semiconductor laser element 30 and the seed light S2 generated by the DFB semiconductor laser element 32 are synchronized. The seed lights S1 and S2 both have substantially the same energy per pulse, but the polarization states are different from each other, and the seed light S1 has a stronger peak intensity. The seed light S1 and the seed light S2 are linearly polarized light, and their polarization directions are orthogonal to each other. In the first embodiment, the polarization state of the seed light S1 generated by the DFB semiconductor laser element 30 will be described as S-polarized light, and the polarization state of the seed light S2 generated by the DFB semiconductor laser element 32 will be described as P-polarized light. The seed lights S1 and S2 are light in the infrared wavelength region.

The control circuit 22 controls the DFB semiconductor laser elements 30 and 32 so that the seed lights S1 and S2 emit light in response to the clock pulse of the clock signal LTC sent from the signal generation unit 22a. As a result, the DFB semiconductor laser elements 30 and 32 simultaneously emit seed lights S1 and S2 at a predetermined frequency (oscillation frequency) Fa in response to each clock pulse (oscillation frequency Fa) of the clock signal LTC. The control circuit 22 is controlled by the drawing control unit 100 in the control device 16. The clock pulse period (= 1 / Fa) of this clock signal LTC is referred to as a reference period Ta. The seed lights S1 and S2 generated by the DFB semiconductor laser elements 30 and 32 are guided to the polarizing beam splitter 34.

The clock signal LTC, which is the reference clock signal, will be described in detail later, but specifies the address in the row direction (main scanning direction) in the memory circuit that stores the bitmap-like drawing pattern data of the drawing data storage unit 108. This is the base of the pixel shift pulse BSC supplied to the address counter (register) for the clock. Further, the signal generation unit 22a contains the overall magnification correction information TMg for performing the overall magnification correction of the drawing line SLn on the irradiated surface of the substrate P, and the local magnification correction information for performing the local magnification correction of the drawing line SLn. CMg is sent from the drawing control unit 100 in the control device 16. As a result, the length (scanning length) of the drawing line SLn on the irradiated surface of the substrate P can be finely adjusted from the ppm order to the% order. The expansion and contraction of the drawing line SLn (fine adjustment of the scanning length) can be performed within the range of the maximum scanning length (for example, 31 mm) of the drawing line SLn. The overall magnification correction in the first embodiment is projected along the main scanning direction while keeping the number of spot light SPs corresponding to one pixel (1 bit) on the drawing data constant. By uniformly fine-tuning the projection interval of the spot light SP (that is, the period of the clock signal LTC), the magnification in the scanning direction of the entire drawing line SLn is uniformly corrected. Further, the local magnification correction in the first embodiment is a spot projected along the main scanning direction only at some discrete correction points (pixel positions) set on one drawing line. By temporarily increasing or decreasing the projection interval of the optical SP (that is, the period of the clock signal LTC), the size of the pixels on the substrate corresponding to the correction point is slightly expanded or contracted in the main scanning direction.

The polarized beam splitter 34 transmits S-polarized light and reflects P-polarized light, and includes seed light S1 generated by the DFB semiconductor laser element 30 and seed light S2 generated by the DFB semiconductor laser element 32. Is led to the electro-optical element 36. That is, the polarization beam splitter 34 guides the seed light S1 to the electro-optical element 36 by transmitting the S-polarized seed light S1 generated by the DFB semiconductor laser element 30. Further, the polarization beam splitter 34 guides the seed light S2 to the electro-optical element 36 by reflecting the P-polarized seed light S2 generated by the DFB semiconductor laser element 32. The DFB semiconductor laser elements 30 and 32 and the polarizing beam splitter 34 constitute a pulse light source unit 35 that generates seed lights S1 and S2.

The electro-optical element (intensity modulation unit) 36 has transparency to the seed lights S1 and S2, and for example, an electro-optic modulator (EOM) is used. Since the seed lights S1 and S2 from each of the DFB semiconductor laser element 30 and the DFB semiconductor laser element 32 have a long wavelength range of 800 nm or more, the electro-optical element 36 having a polarization state switching response of about GHz should be used. Can be done. The electro-optical element 36 switches the polarization states of the seed lights S1 and S2 by the drive circuit 36a in response to the high / low state of the drawing switch signal SHT. The drawing switch signal SHT goes into a high state immediately before any of the scanning units U1 to U6 starts drawing or a certain time before the start of drawing, and all of the scanning units U1 to U6 draw. When it is not in the state, it becomes the low state. The drawing switch signal SHT is transmitted from the drawing control unit 100 that monitors the generation state of the origin signals SZ1 to SZ6 in FIG. 6 via the polygon mirror driving unit 102.

When the drawing switch signal SHT input to the drive circuit 36a is in the low (“0”) state, the electro-optical element 36 leads to the polarization beam splitter 38 as it is without changing the polarization states of the seed lights S1 and S2. On the contrary, when the drawing switch signal SHT input to the drive circuit 36a is in the high (“1”) state, the electro-optical element 36 changes the polarization state of the incident seed lights S1 and S2, that is, the polarization direction is changed. It is changed by 90 degrees and led to the polarization beam splitter 38. By driving the electro-optical element 36 in this way, the electro-optical element 36 uses the S-polarized seed light S1 as the P-polarized seed when the drawing switch signal SHT is in the high state (“1”). It is converted into light S1 and P-polarized seed light S2 is converted into S-polarized seed light S2.

The polarization beam splitter 38 transmits P-polarized light, guides it to the combiner 44 via the lens element GL, reflects S-polarized light, and guides it to the absorber 40. The light (seed light) transmitted through the polarization beam splitter 38 is represented by the beam Lse. The oscillation frequency of this pulsed beam Lse is Fa. The excitation light source 42 generates excitation light, and the excitation light is guided to the combiner 44 through the optical fiber 42a. The combiner 44 synthesizes the beam Lse emitted from the polarizing beam splitter 38 and the excitation light and outputs the excitation light to the fiber optical amplifier 46. The fiber optical amplifier 46 is doped with a laser medium excited by excitation light. Therefore, in the fiber optical amplifier 46 through which the synthesized beam Lse and the excitation light are transmitted, the beam Lse as the seed light is amplified by the excitation of the laser medium by the excitation light. As the laser medium doped in the fiber optical amplifier 46, rare earth elements such as erbium (Er), ytterbium (Yb), and thulium (Tm) are used. The amplified beam Lse is radiated from the emission end 46a of the fiber optical amplifier 46 with a predetermined divergence angle, converged or collimated by the lens element GL, and is incident on the wavelength conversion optical element 48.

The wavelength conversion optical element (first wavelength conversion optical element) 48 uses the second Harmonic Generation (SHG) to generate the incident beam Lse (wavelength λ) by the second harmonic generation (SHG). Convert to harmonics. As the wavelength conversion optical element 48, a PPLN (Periodically Poled LiNbO3) crystal, which is a quasi phase matching (QPM) crystal, is preferably used. It is also possible to use PPLT (Periodically Poled LiTaO3) crystals and the like.

The wavelength conversion optical element (second wavelength conversion optical element) 50 includes the second harmonic (wavelength λ / 2) converted by the wavelength conversion optical element 48 and the seed light remaining without being converted by the wavelength conversion optical element 48. Sum frequency generation (SFG) with (wavelength λ) generates a third harmonic with a wavelength of 1/3 of λ. This third harmonic becomes ultraviolet light (beam LB) having a peak wavelength in a wavelength band of 370 mm or less (for example, 355 nm).

When the drawing switch signal SHT applied to the drive circuit 36a is low (“0”), the electro-optical element (intensity modulator) 36 does not change the polarization state of the incident seed lights S1 and S2, and the polarization beam splitter 38 as it is. Lead to. Therefore, the beam Lse that passes through the polarization beam splitter 38 becomes the seed light S2. In this case, the beam Lse has a low pulse peak intensity and has a dull characteristic that is broad in time. Since the fiber optical amplifier 46 has low amplification efficiency for the seed light S2 having such a low peak intensity, the beam LB emitted from the light source device LS becomes light that is not amplified to the energy required for exposure. Therefore, from the viewpoint of exposure, the result is substantially the same as when the light source device LS does not emit the beam LB. That is, the intensity of the spot light SP applied to the substrate P is at an extremely low level. However, even during the period when the pattern is not exposed (non-drawing period), the beam LB in the ultraviolet region derived from the seed light S2 continues to be irradiated, although the intensity is slight. Therefore, when the drawing lines SL1 to SL6 continue to be in the same position on the substrate P for a long time (for example, when the substrate P is stopped due to a trouble in the transport system), the beam LB of the light source device LS A movable shutter may be provided on the injection window (not shown) to close the injection window.

On the other hand, when the drawing switch signal SHT applied to the drive circuit 36a is high (“1”), the electro-optical element (intensity modulator) 36 changes the polarization state of the incident seed lights S1 and S2 to cause the polarization beam splitter 38. Lead to. Therefore, the beam Lse transmitted through the polarizing beam splitter 38 is generated from the seed light S1 from the DFB semiconductor laser element 30. Since the seed light S1 from the DFB semiconductor laser element 30 has a strong peak intensity, it is efficiently amplified by the fiber optical amplifier 46, and the P-polarized beam LB output from the light source device LS is the energy required for the exposure of the substrate P. have. That is, the intensity of the spot light SP irradiated to the substrate P becomes a high level. In this way, since the electro-optical element 36 that responds to the drawing switch signal SHT is provided in the light source device LS, scanning is performed only during the period in which the drawing operation is performed by scanning the spot light SP while the polygon mirror PM is rotating. The beams LB (LB1 to LB6) can be sent to the units U1 to U6.

In the configuration of FIG. 7, the DFB semiconductor laser element 32 and the polarizing beam splitter 34 are omitted, and only the seed light S1 from the DFB semiconductor laser element 30 is switched by switching the polarization state of the electro-optical element 36, so that the fiber optical amplifier 46 It is also conceivable to guide the light in a burst wave shape. However, when this configuration is adopted, the pattern to be drawn by the incident periodicity (frequency Fa) of the seed light S1 to the fiber optical amplifier 46 and the scanning period of the spot light SP along the drawing line SLn (each surface of the polygon mirror PM). It is greatly disturbed according to the reflection period of the beam LBn at. That is, if the seed light S1 from the DFB semiconductor laser element 30 does not enter the fiber optical amplifier 46 and then the seed light S1 suddenly enters the fiber optical amplifier 46, the seed light S1 immediately after the incident becomes more than usual. Is amplified with a large amplification factor, and there is a problem that a beam having a intensity higher than a specified value is generated from the fiber optical amplifier 46. Therefore, in the present embodiment, as a preferred embodiment, during the period when the seed light S1 is not incident on the fiber optical amplifier 46, the seed light S2 from the DFB semiconductor laser element 32 (time-broad pulse light with a low peak intensity). Is incident on the fiber optical amplifier 46 to solve such a problem.

FIG. 8 is a diagram for explaining the timing of reading drawing data (pixel data string DLn) according to the moving position (moving amount) of the substrate P by the drawing control unit 100 and the drawing data storage unit 108 shown in FIG. Is. Further, here, the drawing operation by the scanning unit U1 will be described as a representative. When the drawing magnification correction for the sub-scanning direction (X-scan direction) is not performed (magnification = 1.0), the encoder EN2a (or EN2b) corresponding to the scanning unit U1 counts with the encoder counter unit (digital counter) 106. The count value to be counted corresponds to the rotation position of the rotary drum DR, that is, the movement amount (or movement position) of the substrate P, and is referred to as CX2. In FIG. 8, the movement amount CX2 is schematically represented by a sequence of up / down pulses supplied to the corresponding counter circuit in the encoder counter unit 106. The measurement resolution of the movement amount (movement position) CX2 is set here to be smaller than the effective diameter size φ of the spot light SP. In the present embodiment, the drawing data storage unit is a bitmap data in which the drawing data is divided into a matrix in the main scanning direction (Y scanning direction) and the sub scanning direction (X scanning direction) in a pixel unit as one bit. It is stored in (data storage unit) 108. The encoder counter unit 106, scale units SDa and SDb, and encoders ENja and ENjb form a measurement mechanism.

It is assumed that one pixel on the drawing data is set to a 3 μm square on the substrate P, which is about the same as the size φ of the spot light SP, for example. Further, since the spot light SP is projected onto the substrate P by overlapping 1/2 of the size φ of the spot light SP in the main scanning direction (Y scanning direction) and the sub scanning direction (X scanning direction). Two spot light SPs correspond to one pixel along the main scanning direction and the sub-scanning direction. Therefore, when the resolution of the movement amount CX2 of the substrate P counted by the encoder counter unit 106 is 1 / k of the pixel size (k is preferably 2 or more) and 0.3 μm per count (1 / k). (When k is 10), the drawing control unit 100 (or the drawing data storage unit 108) sends the address of the drawing data stored in the memory of the drawing data storage unit 108 in the X scan direction every 10 counts of the movement amount CX2. Generates signal XA2 that increments (X address value) one by one. The drawing data storage unit 108 accesses the pixel data string DL1 for one row arranged in the Y scan direction in response to the signal XA2. Further, the drawing data storage unit 108 responds to the pixel shift pulse BSC obtained by dividing the clock signal LTC by 1/2, and sets the address (Y address value) of the accessed pixel data string DL1 in the Y scan direction. Designated, the bit data (“0” or “1”) of the corresponding pixel is serially output to the AOM drive unit 110. As shown in FIG. 8, the period of the pixel shift pulse BSC is twice the period of the clock signal LTC, and the oscillation frequency Fa of the clock signal LTC and the rotation speed Vp of the polygon mirror PM are synchronized along the drawing line SL1. The spot light SP scanned in the above direction can be overlapped by 1/2 of the size φ. In the spot light SP shown in FIG. 8, the solid line represents the spot light SP that reaches the substrate P by pulse emission, and the broken line represents the pulse emission (spot light SP) that is not irradiated to the substrate P. Here, the X address It represents the case where the pixel data string DL1 (00011 ...) With a value of 1 is drawn.

In the above example, the ratio k of the resolution (movement amount for one count) of the movement amount CX2 of the substrate P counted by the encoder counter unit 106 and the pixel size Pxy is an integer (for simplicity of explanation). 10). However, depending on the pitch of the scale (diffraction grating) of the scale units SDa and SDb and the configuration of the encoder heads ENja and ENjb, the ratio k of the measurement resolution (movement amount per count) and the pixel size Pxy may not be an integer. is there. For example, when the actual measurement resolution of the encoder system is 0.312 μm / count, and the design pixel size Pxy is 3 μm square, the ratio k is about 9.615 ... (= 3/0). .312). In this case, assuming that the movement amount CX2 described with reference to FIGS. 9A to 11 is 10 counts as the design pixel size Pxy, the actual movement amount of the substrate P is 3.12 μm, which is about 4% per pixel ( = 0.12 / 3) expansion error rate. Therefore, if pattern drawing is continued in the sub-scanning direction in that state, the pattern drawn in the exposure area W is expanded in the sub-scanning direction by 4% as a whole without correcting the drawing magnification in the sub-scanning direction. Will be done. This is the accumulation of errors less than the LSB (least significant bit) that occur during digital counting.

Therefore, one countermeasure is that the count value of the movement amount CX2 of the substrate P counted by the encoder counter unit 106 is the error rate per pixel (actual 1 count with respect to the movement amount of 1 count assumed in the design). The cumulative error can be eliminated by performing a rounding operation for one count each time the number increases by the number corresponding to the reciprocal of the reciprocal of the movement amount of the minute. For example, in the above example, when the error rate per pixel is + 4% (0.04), the count value of the movement amount CX2 of the substrate P counted by the encoder counter unit 106 is the reciprocal of the error rate. Every time a certain 25 (= 1 / 0.04) count is performed, an address counter that does not count the next 1 count or increments so as not to count the 25th count may be provided. As another countermeasure, there is also a method of setting the design pixel size Pxy according to the actual movement amount (for example, 0.312 μm) for one count counted by the encoder counter unit 106. In this method, assuming that the pixel dimension Pxy of the drawing data prepared in advance when using the exposure apparatus (pattern drawing apparatus) EX of the present embodiment is 3.12 μm square, for example, the CAD data of the pattern is bitmap data. It can be converted to.

As shown in FIG. 8, in the drawing control unit 100, the movement amount (movement position) CX2 measured based on the count value of the encoder counter unit 106 coincides with the drawing line SL1 and the tip of the exposure area W. When the drawing start position Wst in the sub-scanning direction is matched, the generation of the signal XA2 is started and the X address value is sequentially incremented. It is preferable that the drawing control unit 100 recounts the movement amount CX2 from zero with the drawing start position Wst as the zero point (start point) and generates it as an X address value. Further, as the substrate P moves in the sub-scanning direction, scanning of the spot light SP along the drawing line SL1 is repeated at a pitch ΔXP in the sub-scanning direction. In the standard exposure mode, the pitch ΔXP is set to be about ½ of the effective size φ of the spot light SP on the substrate P. That is, the X-scan direction of one pixel is also controlled so as to be drawn by two spot light SPs. However, in the present embodiment, the pitch ΔXP is obtained by reducing the moving speed of the substrate P without changing the oscillation frequency Fa (pulse emission frequency of the beam LB) of the clock signal LTC and the rotation speed of the polygon mirror PM. Can be set to a multiple exposure mode in which one pixel is exposed by a large number of main scans of three or more times, and the amount of exposure during pattern exposure can be increased.

As described above, in the normal exposure mode or the multiple exposure mode, the pattern based on the drawing data is precisely drawn according to the movement amount CX2 of the substrate P. However, it becomes necessary to expand and contract the pattern to be drawn in the sub-scanning direction in response to the deformation of the substrate P. Therefore, in the present embodiment, as shown in FIGS. 9A and 9B, the movement amount CX2 of the substrate P counted by the encoder counter unit 106 and the address (X address value) in the X scanning direction on the drawing data. By shifting the correspondence relationship from the standard relationship, the drawing magnification is corrected with respect to the sub-scanning direction. FIG. 9A shows a state in which the increment of the X address value (increment of address 1) corresponds to 10 counts of the movement amount CX2 when the magnification correction is not performed, and FIG. 9B shows a pattern to be drawn. In order to reduce the size, the increment of the X address value (increment of the address 1) corresponds to 9 counts of the movement amount CX2. In this case, the dimension Px of one pixel drawn on the substrate P in the X direction is reduced to 2.7 μm, where the design pixel dimension Pxy is 3 μm square. Therefore, the pattern exposed on the substrate P by the position where the X address value is 10 shrinks by one pixel (3 μm) in the sub-scanning direction with respect to the pattern exposed without magnification correction. On the contrary, when the pattern to be drawn is enlarged, the increment of the X address value (increment of the first address) may be controlled so as to correspond to 11 counts of the movement amount CX2.

As described above, whether the X address value is incremented before the movement amount CX2 of the substrate P reaches the design pixel size Px, or the X address value is incremented when the design pixel size Px is exceeded. You can switch the drawing magnification to reduction or enlargement by selecting. Further, the timing of changing the relationship between the design dimension Px and the movement amount CX2 regarding the sub-scanning direction of one pixel from the reference state (pixel position in the X-scan direction) does not have to be performed for all X address values, for example. While the X address value advances to No. 10, the X address value is incremented by 10 counts (reference state) of the movement amount CX2, and when the X address value becomes the 11th, 9 counts (or 11) of the movement amount CX2. The X address value is incremented by (count), and when the X address value becomes the 12th, the X address value is incremented again by 10 counts (reference state) of the movement amount CX2, and the next 20th X address. You may continue to the value. Such correction (% or ppm) of the drawing magnification in the sub-scanning direction may not be able to secure good overlay accuracy and splicing accuracy only by making it uniform within one exposure region W of the substrate P, and exposure. While the region W is being exposed in the sub-scanning direction, it becomes necessary to gradually shift to a different magnification correction amount.

FIG. 10 is a diagram illustrating control when changing to a different drawing magnification during the drawing operation. In FIG. 10, when the magnification is not corrected, it is assumed that one pixel corresponds to 10 counts of the movement amount CX2, and the state from the drawing start position Wst to the movement amount CX2 of about 90 counts is shown. At the drawing start position Wst, it is assumed that the drawing magnification is set to 1.0 times (initial value), and the enlargement magnification change point Xm1 is set at a position where the movement amount CX2 becomes 65 counts. This magnification change point Xm1 is estimated from, for example, the arrangement state of a plurality of alignment marks MK1 to MK4 on the substrate P detected by the alignment microscope AM1m, and the drawing control unit 100 is from the drawing start position Wst. The distance, that is, the movement amount CX2 measured by the encoder counter unit 106 manages the magnification change point Xm1. However, as shown in FIG. 10, the magnification change point Xm1 is a period for drawing the pixel data string DLn corresponding to the X address value No. 6, and the magnification is assumed so that the drawing magnification is immediately corrected from the magnification change point Xm1. When the movement amount CX2 is 9 counts or 11 counts from the change point Xm1 and the X address value is incremented, the X address value is the 6th pixel data string. The 7th pixel data string in the middle of drawing the DLn (spot scanning). It is switched to DLn, and the pixel corresponding to the sixth pixel data string DLn is drawn halfway or is missing. That is, the continuity of pixels (patterns) in the sub-scanning direction is impaired. Regarding the sub-scanning direction, when one pixel is drawn by two spot scans so as to overlap at 1/2 of the size φ of the spot light SP, or by lowering the transport speed Vt of the substrate P, the sub-scanning is performed. Even in the case of the multiple drawing mode in which one pixel is drawn by spot scanning three or more times with respect to the direction to increase the exposure amount, the pixel of the X address value depends on the position of the magnification change point Xm1 within the X address value. The data string DLn may be missing, or the exposure amount may be insufficient (which may cause disconnection).

Therefore, in the present embodiment, as shown in the lower part of FIG. 10, the drawing control unit (control unit) 100 has the fifth X address value and the sixth X address value at which drawing normally ends immediately before the initial magnification change point Xm1. The position Xm1'(60th count) on the movement amount CX2 located at the boundary with the X address value of is set as a new magnification change point (new change point) in the calculation. Then, from the time when the moving position of the substrate P becomes the position Xm1', the pixel data string DLn of the sixth X address value read from the drawing data storage unit 108 is shown in FIG. 8 every time the moving amount CX2 advances by 11 counts. The indicated signal XA2 (pulse) is generated and the X address value is incremented. After that, until the next magnification change point is reached, the signal XA2 is generated (increment of the X address value) every time the movement amount CX2 advances by 11 counts (9 counts in the case of reduction). Then, at the next magnification change point set on the movement amount CX2, a new magnification change point (new change point) is similarly set in the calculation. Here, the new change point (position Xm1') is set to the position before the initial magnification change point Xm1, but the pixel data string DLn of the sixth X address value drawn at the initial magnification change point Xm1 is Drawing is performed with the same magnification correction value as the pixel data string DLn of the 5th X address value, and the 70th count at which the drawing of the pixel data string DLn of the 6th X address value is completed is set as the new change Xm1'. You can also do it.

Here, the magnification coefficient set at the drawing start position Wst where the movement amount CX2 becomes zero is set to ΔMx (0), and the first magnification change point (position) on the movement amount CX2 is set at Xm1 and the position Xm1 or later. The magnification coefficient is ΔMx (1), the X address value of the current pixel data string DLn being drawn is XA2 (1), and the new change (position) on the movement amount CX2 in which the position Xm1 is changed is Xm1'. And. Further, the magnification coefficient (correction coefficient) ΔMx (0) and ΔMx (1) are, for example, any of the counts 9, 10 and 11 of the movement amount CX2 set per pixel. In addition, the offset value of the X address value (X address value at the previous new change point) set for the calculation of the new change point (position) Xm2' where the magnification correction is performed after the new change point Xm1'is set. Let it be XAo. When set in this way, the new change Xm1'is calculated by the following equation (1).
Xm1'= Wst + {XA2 (1) -XAo} ・ ΔMx (0) ・ ・ ・ (1)

Here, as shown in FIG. 10, the movement amount CX2 of the drawing start position Wst is zero, the X address value XA2 (1) of the current pixel data string DLn in which drawing is performed is 6, and the offset value XAo is zero. Since the magnification coefficient ΔMx (0) is 10 counts, the new change Xm1'is the 60th count.

In this way, after the magnification coefficient is changed from ΔMx (0) to ΔMx (1) at the new change point Xm1', the X address value XA2 is incremented every 11 counts of the movement amount CX2, and the X address value XA2 The pixel data string DLn is read out in the order of No. 7, No. 8, No. 9, ..., And pattern drawing is performed. Then, as shown in FIG. 11, the next magnification change point Xm2 is designated, for example, at the 118th count (11th pixel data string DLn) on the movement amount CX2, and from the magnification change point Xm2, the magnification coefficient ΔMx (1). It is assumed that the magnification coefficient ΔMx (2) is set differently from that of). Here, the magnification coefficient ΔMx (2) is set to 10 counts, which is an initial value for not performing magnification correction, and the X address value of the current pixel data string DLn in which drawing is performed is set to XA2 (2). .. In this case, the new change Xm2'shown in FIG. 11 is calculated by the following equation (2).
Xm2'= Xm1'+ {XA2 (2) -XAo} ・ ΔMx (1) ・ ・ ・ (2)

Here, as shown in FIG. 11, the previous new change Xm1'is 60, the X address value XA2 (2) of the current pixel data string DLn being drawn is 11, and the offset value XAo (that is, that is). Since the X address value XA2 (1)) at the previous new change Xm1'is 6 and the magnification coefficient ΔMx (1) is 11 counts, the new change Xm2'is calculated as the 115th count. Then, in the drawing of the pixel data string DLn in which the X address value XA2 (2) is the 11th, the X address value is incremented when the movement amount CX2 advances by 10 counts, and the drawing data of the next address (12th in this case) is drawn. Controls columns to be accessed (read). In addition, in FIGS. 10 and 11, the case where the pixel in the X scan direction from the new change point (position) Xm1'to the new change point Xm2' is extended is taken as an example, but when it is reduced, the movement amount CX2 The signal XA2 (pulse) may be generated and the X address value may be incremented every time the signal advances by 9 counts.

FIG. 12 is a diagram for explaining an example of the magnification change point Xmn set on one exposure region (pattern formation region) W, and when viewed on the XYZ coordinate system, the tip on the + X direction side in the exposure region W is the tip. As a unit (drawing start point Wst), position detection of a plurality of alignment marks MK1 to MK4 by the alignment microscopes AM11 to AM14 and drawing (exposure) proceed sequentially in the −X direction. While the substrate P moves in the + X direction at a constant speed, the magnification correction information (magnification change point Xmn, magnification coefficient ΔMx, etc.) in the sub-scanning direction (X direction) based on the result of position detection of the alignment marks MK1 to MK4, etc. ) Are generated sequentially. The alignment marks MK1 and MK4 arranged on both sides of the exposure region W in the Y direction are provided at intervals of 10 mm in design along the X direction, for example. In the measurement of the magnification error using the alignment microscopes AM11 to AM14, the distance between at least two alignment marks MK1 arranged adjacent to each other in the X direction and the distance between at least two alignment marks MK4 arranged adjacent to each other in the X direction are the encoders. It is obtained based on the count value in the counter circuit corresponding to each of EN1a and EN1b, and is compared with the design interval (10 mm) to obtain the magnification error (%, ppm).

In FIG. 12, the drawing start position Wst of the exposure area W is set to the magnification change point Xm0 in which the initial magnification coefficient ΔMx (0) is set. In the case of this kind of flexible long substrate P, even near the drawing start position Wst of the exposure region W, depending on the fluctuation of the transport state of the substrate P until just before being supported by the rotating drum DR, the sub-scanning direction Magnification error may occur significantly. Therefore, in order to obtain the initial magnification coefficient ΔMx (0), the alignment marks MK1 to MK4 (margins or the front) arranged before the drawing start position Wst of the exposure region W by the alignment microscopes AM11 to AM14. The mark formed accompanying the exposed area) is detected, and the drawing control unit 100 calculates the magnification coefficient ΔMx (0) at the magnification change point Xm0 (drawing start position Wst) in consideration of the measurement result.

After that, as the substrate P moves in the + X direction, the position detection of the alignment marks MK1 and MK4 by the alignment microscopes AM11 and AM14 and the measurement of the magnification error are continuously executed, and as a result, the drawing control unit (magnification setting). Unit, control unit) 100 sets a new magnification coefficient ΔMx (1) to be corrected and a magnification change point Xm1 when it is determined that the initial magnification coefficient ΔMx (0) should be corrected. The drawing start point Wst of the exposure area W is an odd number when the substrate P moves in the + X direction by a certain distance after the position detection of the alignment marks MK1 and MK4 and the measurement of the magnification error by the alignment microscopes AM11 and AM14 are started. Drawing lines SL1, SL3, SL5 are reached, a pattern is drawn with a magnification coefficient ΔMx (0) in the sub-scanning direction, and then drawing lines SL2, SL4, whose drawing start position Wst of the exposure area W is an even number. When SL6 is reached, a pattern is drawn with a magnification coefficient ΔMx (0) in the sub-scanning direction.

In this way, as the substrate P moves in the + X direction, the magnification error in the sub-scanning direction is sequentially measured, and as shown in FIG. 12, for example, the magnification change points Xm2 to Xm5 and the magnification coefficient ΔMx (2) to ΔMx (5) is set in sequence. In FIG. 12, for the sake of explanation, the magnification coefficients ΔMx (0) to ΔMx (5) and the magnification change points Xm0 to Xm5 are set for each of the six regions in the X direction in the exposure region W. , The magnification coefficient ΔMx (n) and the magnification change point Xmn may be set every interval (for example, 10 mm) of the alignment marks MK1 and MK4 in the X direction, or every 1/2 (5 mm) thereof. .. In this way, when the magnification change point Xmn is finely set in the sub-scanning direction, for example, the magnification coefficient ΔMx (n) is set to enlargement or reduction while the substrate P moves 10 mm (or 5 mm) in the + X direction. While the substrate P continues to move 10 mm (or 5 mm) in the + X direction, the magnification coefficient ΔMx (n + 1) may be repeatedly set to the same magnification (neither enlargement nor reduction). In the present embodiment, as described above, the drawing magnification can be finely corrected with respect to the magnification error due to the expansion and contraction of the substrate P in the sub-scanning direction, and the overlay accuracy is well maintained over the entire surface of the exposure region W. be able to.

[Modification Example] FIG. 13 is a diagram (time chart) for explaining a modification of the calculation sequence for correcting the drawing magnification in the sub-scanning direction executed by the drawing control unit 100 shown in FIG. Here, the arithmetic sequence for the scanning unit U1 will be described as a representative, but the same sequence will be executed in the other scanning units U2 to U6. The drawing control unit 100 sequentially and repeatedly executes the two processes A and B shown in FIG. Process A is sequentially executed in response to the origin signal SZ1 (pulse signal) sent from the scanning unit U1, and process B is generated with a period Tpk shorter than the period Tpx at which the origin signal SZ1 (pulse signal) is generated. The timing signal (internal clock pulse signal) is sequentially executed in response to SK1. Here, it is assumed that the period Tpk is set to about 1/3 of the period Tpx. The maximum processing time of the routine processing of the processing B is set so as to be within the period Tpk.

The process A executed for each pulse of the origin signal SZ1 includes step SA1 for acquiring the movement amount CX2 (movement distance from the drawing start position Wst of the substrate P) as described in FIGS. 10 and 11, and the movement amount. It includes step SA2 for calculating and setting the X address value XA2 (n) in the drawing data memory corresponding to CX2. In the process B executed for each pulse of the signal SK1, the step SB1 for acquiring the movement amount CX2 and the following magnification change points where the acquired movement amount CX2 (current position) is as described with reference to FIGS. In step SB2 for determining whether or not Xmn has passed, and when CX2 ≧ Xmn, the offset value XAo of the X address value and the new change point Xmn'explained above are calculated, and the next magnification coefficient ΔMx (n) is calculated. Includes step SB3 to change to. In the calculation of the X address value XA2 (n) in step SA2, assuming that the magnification coefficient set at the time of executing the process A is ΔMx (n-1), the following integer calculation is performed by rounding or rounding down the decimal point.
XA2 (n) = {CX2-Xm (n-1)'} / ΔMx (n-1) + XAo
It is calculated by.

In this way, by arranging the processes A and B in parallel for each period Tpx of the origin signal SZ1 and for each period Tpk shorter than the period Tpx of the origin signal SZ1, at the change point Xmn of the drawing magnification in the sub-scanning direction. The drawing of one pixel in the sub-scanning direction is not halfway or disappears, and precise pattern drawing is performed.

[Second Embodiment]
In the first embodiment and modification, the start of drawing by the spot light SP along each of the drawing lines SL1 to SL6 is the origin sensor OPn (OP1 to OP6) as the detection sensor shown in FIGS. 4 and 6. ) Are generated, and the origin signals SZn (SZ1 to SZ6) are set to be generated immediately. However, in reality, when the origin signal SZn is generated, the pattern drawing is started after the spot light SP runs about 1 mm to several mm on the substrate P after the origin signal SZn (SZ1 to SZ6) is generated. A delay circuit (hardware or software) that starts drawing after a predetermined delay time ΔTss is provided. As illustrated above, the scanning time Tsp of one scan of the spot light SP along the drawing line SLn is about 200 μsec, and the maximum scanning length of the spot light SP on the substrate P is 32 mm (effective drawing range 30 mm). If an additional range of 1 mm is provided before and after the above, the scanning speed Vs of the spot light SP is 160 μm / μsec. Therefore, if the delay time ΔTss is changed by ± 1 μsec with respect to the initial value, the pattern drawn on the substrate P can be position-shifted by ± 160 μm in the main scanning direction (Y direction). Normally, the time from the generation of the origin signal SZn to the actual start of drawing is set as short as possible. Therefore, when reducing the delay time ΔTss from the initial value, the time from the time when the origin signal SZn is generated is set. The interval time to the start of drawing becomes shorter. Therefore, it takes time to calculate the address value in the memory of the pixel data string DLn to be drawn by the start of drawing, and to calculate various correction values (magnification correction amount, Y position shift amount, etc.). It may be longer than the interval time, and the pattern to be drawn may be partially missing or greatly disturbed.

Therefore, in the present embodiment, as shown in FIG. 14, reading processing of the pixel data string DLn to be drawn in one scan of the spot light SP (calculation processing of the access address, one column of the pixel data string DLn is bitted. One cycle of the pulse (second detection signal) of the origin signal SZn generated at the timing of actually drawing the preparatory processing such as the correction process and the process of transferring to a register that shifts in units) and the spot light SP of the beam LBn. It is executed in response to the pulse (first detection signal) generated in front of Tpx. FIG. 14 is a time chart showing the generation timing of the origin signal SZ1 from the scanning unit U1, the drawing timing (signal SE1 representing the actual drawing period), and the calculation timing in chronological order. The pulse of the origin signal SZ1 is generated in the order of the continuous reflection surfaces RPa, RPb, RPc, RPd ... Of the polygon mirror PM at a constant period Tpx. In general drawing control, for example, a predetermined delay is given from the time when one pulse of the origin signal SZ1 generated immediately before the rotation angle on which the reflecting surface RPa (RPb to RPd ...) Can be drawn. After the time ΔTss, for example, drawing is performed based on the pixel data string DL1a corresponding to one X address value. That is, in general drawing control, as shown by the calculation timing A, it is necessary to perform access processing and calculation processing of the pixel data string DL1a to be drawn within the delay time ΔTss.

In FIG. 14, DL1a drawing (drawing timing based on the pixel data string DL1a, the same applies hereinafter) represented as drawing timing (signal SE1), DL1b drawing, DL1c drawing, ..., Each of the reflection surface RPa of the polygon mirror PM. , RPb, RPc ... However, since the X address value is incremented when scanning along the drawing line SL1 of the spot light SP is performed twice or a certain number of times, the polygon mirror PM has two or more continuous reflecting surfaces RPa. With RPb, RPc ..., The same pixel data string DL1 is repeatedly drawn a predetermined number of times. Further, in FIG. 14, the pulse of the origin signal SZn generated at the timing when the above-mentioned preparatory process of the pixel data string DLn to be drawn by one scan of the spot light SP is actually drawn by the spot light SP of the beam LBn ( It is executed in response to the pulse (first detection signal) generated one cycle Tpx before the second detection signal), but this is not limited to one cycle Tpx before, and one cycle Tpx or more. It may be a time point before the predetermined time (for example, a pulse of the origin signal SZn generated before two or more cycles). The time before the preparatory process is started is set according to the time required for the preparatory process.

In the present embodiment, as shown in the calculation timing B of FIG. 14, the access processing and the calculation processing of the pixel data string DL1 are performed in advance in response to one pulse of the origin signal SZ1, and are next to the origin signal SZ1. Make the actual drawing start in response to the pulse. In this way, the time for performing the access processing and the arithmetic processing of the pixel data string DL1 can be secured up to the time of the periodic Tpx, and the access processing and the arithmetic processing of the pixel data string DL1 can be reliably executed. it can. Further, in the case of the calculation timing A, the delay time ΔTss cannot be shortened to less than that because it is necessary to secure the minimum time for the access processing of the pixel data string DL1. Therefore, the range in which the drawn pattern can be position-shifted in the Y direction is limited. However, in the present embodiment, the delay time ΔTss can be set from zero, so that the drawn pattern can be set in the Y direction. It is possible to obtain a large range of position shift, and it is possible to obtain good overlay accuracy even when the position of the substrate P in the width direction and the distortion are large.

FIG. 15 is a block diagram illustrating an outline of a partial circuit configuration provided in each of the drawing control unit 100 and the drawing data storage unit 108 in FIG. 6 in order to perform the control described in FIG. Here, too, it is assumed that the drawing control unit 100 and the drawing data storage unit 108 are provided corresponding to the scanning unit U1 as a representative, and the drawing data storage unit 108 contains pattern data to be drawn by the drawing line SL1. It is assumed that it is remembered. The drawing data storage unit 108 stores memory areas 108A0, 108A1, 108A2 ... For storing pixel data strings DL1a, DL1b, DL1c, ... For one drawing line in the main scanning direction accessed by the X address value. A selection unit 108B that selects any one of the memory areas 108A0, 108A1, 108A2 ... (hereinafter, also collectively referred to as 108An) according to the X address value specified by the drawing control unit 100, and a memory area. The and-gate unit 108C for inputting the bit data of the pixel data string DL1 serially output from one memory area selected from 108An and the drawing switch signal SHT described with reference to FIGS. 6 and 7, and the memory area. An and gate that supplies a Y address register 108D that generates a Y address value of one selected memory area of 108 An and a pixel shift signal (pulse signal) BSC for incrementing the Y address value to the Y address register 108D. It is provided with a unit 108E. In FIG. 15, the selection unit 108B applies the pixel data string DL1a from the memory area 108A0 corresponding to the address 0 of the X address value to the andgate unit 108C, and the bit stream (serial 2) of the pixel data string DL1a. The value signal) is supplied as a modulation signal to the drawing optical element AOM1 for the scanning unit U1 via the AOM drive unit 110 in FIG.

The drawing control unit 100 includes a delay time generation unit 100A for inputting the origin signal SZ1 from the scanning unit U1 via the polygon mirror drive unit 102 in FIG. The delay time generation unit 100A outputs the signal SE1 as shown in FIG. 14 after the designated delay time ΔTss has elapsed from the time when one pulse of the origin signal SZ1 is generated. The signal SE1 is sent to one input of the and-gate unit 108E in the drawing data storage unit 108, and the pixel shift signal (pulse) BSC applied to the other input of the and-gate unit 108E is passed through the Y address register 108D. It switches at high speed whether or not to use it. The function of the delay time generation unit 100A may be realized by program processing by the CPU of the drawing control unit 100, or may be realized by hardware by FPGA (field programmable gate array).

Here, the delay time ΔTss set in the delay time generation unit 100A is the delay time from the time when the origin signal SZ1 is generated, but the delay time generation unit 100A itself generates a constant initial delay time ΔTd0. In the case of the configuration, the delay time ΔTss' set in the delay time generation unit 100A may be set to ΔTss'= ΔTss−ΔTd0.

In the above configuration, when one pulse of the origin signal SZ1 as shown in FIG. 14 is input to the delay time generation unit 100A, the delay time generation unit 100A rises to the H level after the delay time ΔTss and spots along the drawing line SL1. A signal SE1 that drops to the L level is generated when a time slightly longer than one scanning time of the optical SP and shorter than the period Tpx at which the origin signal SZ1 generates a pulse has elapsed. The and gate unit 108E supplies the pixel shift signal (pulse signal) BSC as shown in FIG. 8 to the Y address register 108D only while the signal SE1 is at the H level. As a result, the Y address register 108D sequentially increments the Y address value for designating the address in the memory area 108A0 in response to the pulse of the pixel shift signal BSC. In the case of FIG. 15, since the address designated as the X address value is address 0, the pixel data string DL1a serially read from the address 0 (bits) in the memory area 108A0 is via the and-gate unit 108C. It is sent to the AOM drive unit 110, and during scanning of the spot light SP along the drawing line SL1, the intensity of the spot light SP is modulated according to the pixel data string DL1a at address 0 (X address value is 0) in the sub-scanning direction. Will be done.

As illustrated above, when the scanning time Tsp of one scan of the spot light SP along the drawing line SLn is about 200 μsec and the maximum scanning length of the spot light SP on the substrate P is 32 mm, the delay time ΔTss is set. When the change is made by ± 1 μsec (1000 nsec), the pattern drawn on the substrate P is position-shifted by ± 160 μm in the main scanning direction (Y direction). Practically, the adjustment resolution of the position shift is determined by the balance with the overlay accuracy and the minimum dimension (minimum line width) of the pattern to be drawn. For example, if the minimum dimension is 15 μm and the overlay accuracy is ± 3 μm, which is about 1/5 of the minimum dimension, the position shift adjustment resolution also needs to be about 3 μm. Therefore, the delay time generation unit 100A may have a configuration in which the delay time ΔTss (or ΔTss') can be set with a resolution of 18.75 nsec (= 3 μm × 1000 nsec / 160 μm) or less, and may be in the 9 nsec range, for example. When the delay time ΔTss (or ΔTss') is measured by the number of clock pulses, if a clock signal of 107.25 MHz is created, the pulse period of the clock signal becomes 9.324 nsec, and the count of one clock pulse is counted on the substrate P. It can correspond to the position shift of 1.5 μm.

FIG. 16 is a chart diagram showing an example of a case where the position shift of the drawing pattern in the main scanning direction (Y direction) described with reference to FIGS. 14 and 15 is continuously executed during the pattern drawing operation with respect to the exposure area W. Is. In FIG. 16, the horizontal axis represents the time from the drawing start position Wst of the exposure area W or the moving position in the X direction. Here, the movement amount CX2 (or CX1) is up to 500, which is a count value digitally counted from the drawing start position Wst by the counter circuit corresponding to the encoder EN2 (or EN1) (1 count corresponds to, for example, 0.3 μm). It is assumed that the X address value is incremented by the address 1 for 10 counts of the movement amount CX2. The Y shift change points XS0, XS1, and XS2 are exposed areas W (base patterns) calculated by the drawing control unit 100 based on the position information of the alignment marks MK1 to MK4 detected by the alignment microscopes AM11 to AM14 immediately before the start of drawing. ) Is a change in position shift to accommodate the deformation. The shift rates ΔYS0, ΔYS1, and ΔYS2 represent the rate of change (slope) ψ0, ψ1, ψ2 of the position shift that is linearly approximated between the position shift amounts at each of the two Y shift change points XSn and XSn + 1 that are in phase with each other. ..

In FIG. 16, at the drawing start position Wst (time Tx0, position X0), it is assumed that the Y position of the exposure region W is deviated from the design initial position (0) by −YS0 in the Y direction. The initial position (0) is a drawing in the main scanning direction set on the substrate P when the delay time generation unit 100A transitions the signal SE1 to the H level after the initial delay time ΔTd0 from the generation of the pulse of the origin signal SZ1. This is the starting point. As the substrate P moves in the sub-scanning direction (X direction), the alignment microscopes AM11 to AM14 and the encoder EN1 cooperate to sequentially execute the position detection of the alignment marks MK1 and MK4. The drawing control unit 100 calculates the position shift amount based on the detected positions of the plurality of detected alignment marks MK1 and MK4. When the drawing control unit 100 determines that the tendency of the position shift of the exposure region W in the Y direction changes at the position X1, the position shift amount from the initial position (0) at the position X1 (time Tx1) + YS1 and so on. The count value of the movement amount CX2 (CX1) from the position X0 to the position X1 with the difference value from the position shift amount-YS0 from the initial position (0) at the position X0 (time Tx0) which is the drawing start position Wst as the numerator. The shift rate ΔYS0 (change rate ψ0) with the denominator as the denominator is calculated.

As shown in FIG. 3, a plurality of alignments with respect to the moving direction of the substrate P are performed between the positions of the detection regions Vw11 and Vw14 of the alignment microscopes AM11 and AM14 and the positions of the drawing lines SL1, SL3 and SL5. Marks MK1 and MK4 are formed. In the case of FIG. 3, before the positions to be drawn in the exposure area W reach the drawing lines SL1, SL3, and SL5, the alignment microscopes AM11 and AM14 are provided at three or four locations each provided with an interval Dh in the X direction. The positions of the alignment marks MK1 and MK4 can be detected. Therefore, from the position detection results of the plurality of alignment marks MK1 and MK4, the position shift amount and the change rate of the position shift in the Y direction of the exposure region W can be obtained before drawing the pattern.

Hereinafter, in the same manner, each of the plurality of alignment marks MK1 and MK4 is sequentially detected as the substrate P moves, and the tendency of the position shift of the exposure region W in the Y direction again at the next position X2 (time Tx2). When it is determined that the value has changed, the difference between the position shift amount from the initial position (0) at the position X2 + YS2 and the position shift amount at the position X1 (time Tx1) which is the immediately preceding change point + YS1 is calculated. The shift rate ΔYS1 (change rate ψ1) is calculated using the count value of the movement amount CX2 (CX1) from the position X1 to the position X2 as the denominator as the molecule. In this way, the change in the position shift amount of the exposure region W in the Y direction is approximated and sequentially obtained in correspondence with the movement amount CX2 (CX1) of the substrate P in the sub-scanning direction (X direction). When the position shift amounts −YS0, + YS1, + YS2 at each of the positions X0, X1 and X2 are obtained and the shift rates ΔYS0, ΔYS1 ... The value of the delay time ΔTss0 corresponding to the above and the shift rate ΔYS0 are set in the delay time generation unit 100A. The delay time generation unit 100A sets the delay time ΔTss from the initial value ΔTss0 to the shift rate ΔYS0 in the case of FIG. 16 from the time when the drawing lines SL1 (SL3, SL5) and the drawing start position Wst on the substrate P match. The number is gradually increased accordingly. Then, when the substrate P moves to the position X1, the drawing control unit 100 sets the shift rate ΔYS1 in the delay time generation unit 100A with the value of the delay time ΔTss1 corresponding to the position shift amount at the position X1 + YS1 as the initial value. .. As a result, the pattern exposed from the position X0 on the substrate P is sequentially corrected and drawn at the drawing start timing in response to the origin signal SZn so as to follow the tendency of the position shift in the Y direction of the exposure region W.

As described above, the entire drawing line SLn has a high resolution in the Y direction in pixel units (or one scanning unit by the spot light SP) in the sub-scanning direction according to the tendency of the position shift with respect to the main scanning direction of the exposure region W. It can be shifted by (for example, about 1/2 of the pixel size), and the overlay accuracy can be significantly improved over the entire surface of the exposure region W.

[Modification 1] In addition to the position shift of the exposure region W in the Y direction as described above, the dimension of the exposure region W in the width direction (main scanning direction) is ten according to the position of the exposure region W in the sub-scanning direction. It may expand and contract in the range of several ppm to several hundred ppm. The tendency of expansion and contraction of the exposed region W with respect to the main scanning direction can also be estimated by detecting the positions of the alignment marks MK1 to MK4 by the alignment microscopes AM11 and AM14. The drawing magnification correction for the expansion and contraction of the exposure area W in the main scanning direction is performed so that the dimensions of the pattern drawn in each drawing line SLn in the main scanning direction are finely adjusted as described with reference to FIGS. 6 and 7. This is executed by sending information TMg and CMg for correction of drawing magnification from the control unit 100 to the light source device LS.

By sequentially changing the values set in the light source device LS as the information TMg and CMg in association with the movement amount CX2 of the substrate P, it seems that the dimension of the exposure region W in the width direction changes non-linearly with respect to the long direction. Even in such a case, high overlay accuracy can be obtained over the entire surface of the exposed area W. Further, the drawing magnification correction for the expansion / contraction change in the sub-scanning direction of the exposure area W, the drawing position correction for the position shift in the Y direction of the exposure area W, and the drawing magnification correction for the expansion / contraction in the width direction of the exposure area W described above. By executing at least two of these corrections in parallel, a pattern can be drawn with good overlay accuracy even for non-linear deformation of the entire exposure region W.

[Modification 2] In the first embodiment and the second embodiment, the oscillation frequency Fa of the beam LB from the light source device LS and the scanning speed Vs of the spot light SP are set on the substrate P of the spot light SP. It is set so that it overlaps in the main scanning direction at 1/2 of the size φ of, and the pixel unit is set so as to be drawn by two spots of the spot light SP. Further, when the drawing magnification is corrected, the clock of the clock signal LTC is so that the distance between the two spot light SPs continuous in the main scanning direction expands and contracts very slightly at the correction point corresponding to a specific pixel. The period of the pulse was expanded or contracted. However, the oscillation frequency Fa of the beam LB from the light source device LS is increased, the pixel unit is controlled to be drawn by a large number of spot light SPs (pulse light), and the pixels are located at the correction points for correcting the drawing magnification. On the other hand, the number of pulses of the spot light SP may be increased or decreased. For example, the beam LB from the light source device LS of the first embodiment is oscillated at 400 MHz, which is four times 100 MHz, and the main scan is performed on pixels (normal pixels) located outside the correction point for drawing magnification. The spot light SP is drawn with 8 pulses per pixel in terms of direction, and for the pixels (correction pixels) located at the correction points, the spot light SP has 7 pulses for reduction and 9 pulses for enlargement in the main scanning direction. Draw with. In this case, the clock signal LTC that oscillates the beam LB in a pulsed manner may remain at a constant period (in the case of 400 MHz, the period is 2.5 nS) without partially fine-tuning the period.

As described above, in the case of the drawing magnification correction in the main scanning direction for adjusting the number of pulses of the spot light SP per pixel, the access of the image data (pixel data string) stored in the drawing data storage unit 108 is with respect to the normal pixel. When the clock pulse of the clock signal LTC is counted by 8, the Y address value of the memory is incremented by one, and for the correction pixel, when the clock pulse of the clock signal LTC is counted by 7 or 9, the Y address value of the memory is incremented by 1. Just need it. In this way, when each pixel is drawn with a standard 8-pulse spot light SP in the main scanning direction and the design pixel size Pxy is 3 μm square, the normal pixel is drawn at 3 μm square, and the correction pixel is drawn at the time of reduction. It is drawn at about 2.63 μm (7/8 × 3 μm) in the main scanning direction and about 3.38 μm (9/8 × 3 μm) in the main scanning direction when enlarged.

[Modification 3] In both the first embodiment and the second embodiment, a direct drawing type maskless exposure machine that one-dimensionally scans the spot light SP projected on the substrate P by the polygon mirror PM. However, for example, as disclosed in Japanese Patent Application Laid-Open No. 2008-182115, even a maskless exposure machine that draws a pattern using a digital micromirror device (DMD) and a microlens array Good. In that case, if a mechanism for precisely moving the substrate P in the sub-scanning direction and a measurement system such as an encoder or a length measuring interferometer for measuring the movement amount with a resolution equal to or less than the pixel size are provided, the first Similarly, the drawing magnification correction for the sub-scanning direction described in the embodiment and the shift correction for the drawing position for the main scanning direction described in the second embodiment can be performed in the same manner. In the case of a maskless exposure machine equipped with an exposure head including a DMD and a microlens array, whether a light beam deflected by each of the many micromovable mirrors of the DMD is incident on each of the corresponding lenses of the microlens array. By switching at high speed based on the drawing data, the substrate P is moved in the sub-scanning direction while modulating (on / off) the intensities of a large number of spot light SPs distributed two-dimensionally on the substrate P. The pattern is drawn. In the first embodiment, the second embodiment, and each of the modified examples 1 to 3, the substrate P is assumed to move in the sub-scanning direction, but the exposure head side (the entire scanning unit Un) is constant. It may be moved at a predetermined speed in the sub-scanning direction over the distance of.

[Modification 4] In the first embodiment and the second embodiment, as shown in FIG. 6, the rotation angle position of the rotary drum DR counted by the encoder counter unit 106, that is, the length of the substrate P Based on the movement position (or movement amount) in the direction, the address value of the drawing data corresponding to each of the scanning units U1 to U6 stored in the drawing data storage unit 108 is specified every time the spot light SP is scanned. Then, the data was read out, and the pattern was drawn on each of the drawing lines SL1 to SL6. However, as described above, each counter circuit provided in the encoder counter unit 106 and counting the two-phase signals from each of the encoders ENja (EN1a to EN4a) and ENjb (EN1b to EN4b) has a Z-phase mark ZZ. Is reset to zero. Therefore, if the address value of the drawing data stored in the drawing data storage unit 108 is directly generated by the count value (count value) counted by the encoder counter unit 106, a large jump may occur in the address value at the time of zero reset. is there. In order to avoid this, the address value should not be skipped by zero reset while each of the scanning units U1 to U6 is drawing for one exposure area W on the substrate P shown in FIG. In addition, for example, the count value of the counter circuit in the counter unit 106 immediately before the zero reset is latched as an offset value by sequentially monitoring by the program processing by the microprocessor (CPU) unit in the drawing control unit 100, and after the zero reset. May generate the address value of the drawing data stored in the drawing data storage unit 108 based on the value obtained by adding the latched offset value to the count value counted by the counter circuit in the counter unit 106.

In that case, the latched offset value and the count value sent from the encoder counter unit 106 are sequentially added to the microprocessor (CPU) unit in the drawing control unit 100, and the drawing data storage unit 108 An address counter (register) is provided to access the drawing data to be drawn in the memory inside. As a result, this address counter functions as a counter circuit that is not zero-reset by the Z-phase mark ZZ of the encoder scale unit SDa (SDb), and is generated even if each counter circuit in the encoder counter unit 106 is zero-reset. The continuity of address values can be maintained.

However, the microprocessor (CPU) unit in the drawing control unit 100 constantly monitors the occurrence of zero reset of each counter circuit in the encoder counter unit 106, latches the offset value at the time of zero reset, and outputs from the encoder counter unit 106. The addition operation of the count value and the offset value is performed by the interrupt processing, and the series of these processes may be delayed depending on the timing of the interrupt generation. Therefore, a second counter circuit (which functions as an address counter for the memory in the drawing data storage unit 108), which has the same configuration as each counter circuit in the encoder counter unit 106 and is not reset by the Z-phase mark ZZ, is separately provided. Provide. This second counter circuit has a number of digits (number of bits) sufficient to count the grid scale of the scale unit SDa (SDb) over one round or more, preferably several rounds or more of the rotating drum DR. The second counter circuit (plurality) counts two-phase signals from each of the encoders ENja (EN1a to EN4a) and ENjb (EN1b to EN4b), respectively, and each scanning unit U1 to U6 resets the count value. It is performed once at the position of the drawing start point in the long direction of the exposure region W on the substrate P, for example, in response to the origin signal SZn (SZ1 to SZ6). The reset value at that time corresponds to, for example, the start address value of the memory in which the drawing data of the pattern drawn in the exposure area W is stored. By providing the second counter circuits (plurality) in this way, the microprocessor (CPU) unit in the drawing control unit 100 performs interrupt processing in response to the zero reset of each counter circuit in the encoder counter unit 106. This eliminates the need, and the drawing data can be read from the memory in the drawing data storage unit 108 without continuously skipping in time. Six second counter circuits (plural) are provided corresponding to each of the scanning units U1 to U6, and each of the second counter circuits is provided with origin signals SZ1 to 2 from the corresponding scanning units U1 to U6. The pulse of SZ6 may be counted from the start of drawing in the long direction of the exposure area W to generate an address value for the memory in the drawing data storage unit 108.

10 ... Device manufacturing system 12 ... Substrate transfer mechanism 14 ... Exposure head 16 ... Control device 20 ... Pulse light generator 22 ... Control circuit 100 ... Drawing control unit 102 ... Polygon mirror drive unit 104 ... Alignment unit 106 ... Encoder counter unit 108 ... Drawing data storage unit 110 ... AOM drive unit 112 ... Drive control unit AOMn ... Optical element for drawing BDU ... Beam distribution unit DR ... Rotating drum EX ... Exposure device LBn ... Beam LS ... Light source device OP1 ... Origin sensor opa ... Beam light transmission system opb ... Beam light receiving system P ... Substrate PM ... Polygon mirror SP ... Spot light Un ... Scanning unit

Claims (9)

It has a drawing head unit that sequentially deflects the drawing beam on each reflecting surface of the rotating polymorphic mirror and repeatedly scans the spot light of the drawing beam in the main scanning direction on the substrate, and the substrate and the drawing head unit are subordinate to each other. A pattern drawing device that draws a pattern on the substrate for each drawing line formed by scanning the spot light in the main scanning direction by moving the spot light relative to the scanning direction .
Wherein the time when each of the reflection surfaces of the rotary polygon mirror becomes a predetermined angle detected optically, a detection signal indicating that the spot light of the drawing beam becomes a scanning start position in the main scanning direction, wherein A detection sensor that outputs spot light each time it is repeatedly scanned,
Data storage for storing a plurality of drawing data corresponding to the pattern to be drawn while the spot light is scanned in the main scanning direction , corresponding to each of the drawing lines formed side by side in the sub-scanning direction. Department and
The first detection signal output from the detection sensor corresponding to the first reflecting surface of the rotating polymorphic mirror , and then the detection sensor corresponding to the second reflecting surface of the rotating multifaceted mirror. In the period between the second detection signal output from the data storage unit, the drawing data corresponding to the drawing line to be drawn in response to the second detection signal stored in the data storage unit is displayed. run the preparation process of preparing, with the second of the controls to perform the drawing of the pattern by the spot light on the basis of the drawing data the preparation process in response to the detection signal the control unit,
A pattern drawing device. The pattern drawing apparatus according to claim 1.
The data storage unit divides the pattern to be drawn on the substrate into two-dimensional pixels, and stores pixel data strings corresponding to each of the pixels of one row arranged in the main scanning direction as the drawing data. A pattern drawing device that stores a plurality of the pixel data strings corresponding to the pixels arranged in the sub-scanning direction. The pattern drawing apparatus according to claim 2.
The control unit includes a pattern drawing apparatus including a modulator that starts intensity modulation of the drawing beam based on the prepared pixel data string after a predetermined delay time from the generation of the second detection signal. .. The pattern drawing apparatus according to claim 3.
Before Symbol detection sensor, outputs an optical transmitting system for irradiating a detection beam to the reflecting surface of the rotary polygon mirror, the detection signal by receiving the reflected beam on the reflection surface of the rotary polygon mirror of the detection beam Including the light receiving system
The light receiving system is a pattern drawing device that outputs the detection signal at each time when each of the reflecting surfaces of the rotating multifaceted mirror reaches a predetermined angle. The pattern drawing apparatus according to claim 4.
The control unit is a pattern drawing device that shifts the drawing position of the pattern in the main scanning direction by adjusting the delay time. The pattern drawing apparatus according to claim 5.
A pattern drawing apparatus in which the adjustment resolution of the shift of the drawing position by adjusting the delay time is set to be equal to or lower than the overlay accuracy determined according to the minimum line width of the pattern drawn on the substrate. The pattern drawing apparatus according to any one of claims 1 to 6.
In order to generate the drawing beam, a pulse light source unit that generates a seed light that oscillates in a pulse shape at a predetermined frequency Fa, an optical amplifier that amplifies the seed light, and an ultraviolet ray that is incident on the amplified seed light. A pulse light source device including a wavelength conversion element that generates pulsed light in the wavelength range is further provided.
A pattern drawing apparatus in which the spot light of the drawing beam is projected onto the substrate in a pulse shape at the frequency Fa when the pattern is drawn based on the drawing data. The pattern drawing apparatus according to claim 7.
The frequency Fa of the seed light oscillated from the pulse light source unit is per pulse based on the scanning speed of the spot light in the main scanning direction and the effective diameter of the spot light on the substrate. A pattern drawing device in which the spot light of the above is set to overlap in the main scanning direction by at least 1/2 of the diameter. The pattern drawing apparatus according to claim 8.
The frequency Fa is a pattern drawing device set to 100 MHz or 400 MHz.

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