JP6806139B2 - Beam scanning device and pattern drawing device - Google Patents

Description

The present invention relates to a beam scanning device that scans a spot light of a beam irradiated on an irradiated surface of an object, and a pattern drawing device that draws and exposes a predetermined pattern using such a beam scanning device.

Conventionally, as a high-speed printer for office use, the spot light of a laser beam is projected onto an irradiated object (object) such as a photosensitive drum, and the spot light is mainly scanned in a one-dimensional direction by a rotating multifaceted mirror while being covered. In order to move the irradiating body in the sub-scanning direction orthogonal to the main scanning line direction and draw a desired pattern or image (characters, figures, photographs, etc.) on the irradiated body, for example, the following Japanese Patent Application Laid-Open No. It is known to use an optical scanning apparatus such as No. 61-7818.

Japanese Patent Application Laid-Open No. 61-7818 describes a rotating multi-sided mirror having a deflecting reflection surface that rotates about a rotation axis, and two correction mirrors that face the deflection reflection surface so that the ridge line is orthogonal to the rotation axis. A plane mirror is provided, and the incident light beam on the deflecting reflection surface of the rotating multifaceted mirror is reciprocated once with the correction plane mirror to guide it to the scanning surface as a scanning light beam. It is disclosed to optically correct the distortion of. In Japanese Patent Application Laid-Open No. 61-7818, the angle (injection angle) between the projected image of the scanning light beam on the plane orthogonal to the ridgeline of the two correction plane mirrors including the rotation axis and the plane orthogonal to the rotation axis. It is said that the arrangement of the two correction plane mirrors and the incident angle of the incident light beam are set so that is 5 ° to 15 °.

As shown in FIG. 2 (or FIGS. 8 to 10) of JP-A-61-7818, the light beam first incident on the deflecting reflection surface of the rotating polymorphic mirror and the two corrections. When the light beam reflected by the plane mirror and incident on the deflection reflection surface of the rotating multifaceted mirror for the second time is set to the same position on the deflection reflection surface in the direction of the rotation axis, the angle formed by the two correction plane mirrors ( Narrow angle β) is a sharp angle of less than 90 °. In that case, when the deflecting reflection surface of the rotating multifaceted mirror is tilted with respect to the plane parallel to the axis of rotation, the light beam reflected by the two correction plane mirrors and returning to the deflecting reflecting surface of the rotating multifaceted mirror is a rotating multifaceted surface. It will be largely displaced in the direction of the rotation axis with respect to the position of the light beam that first enters the deflecting reflection surface of the mirror. Therefore, it is necessary to secure the dimensions in the rotation axis direction of the deflection reflection surface of the rotary multifaceted mirror so as to correspond to the displacement. As a result, the weight reduction of the rotating multi-sided mirror is limited, and the upper limit of the rotational speed of the rotating multi-sided mirror is regulated.

The first aspect of the present invention is a beam scanning device that projects a beam from a light source device deflected by a movable reflection member whose angle of the reflection surface changes onto an irradiated object, and is first reflected by the movable reflection member. The first reflected beam is reflected to generate a second reflected beam toward the movable reflecting member, and the second reflected beam is generated with respect to a non-deflection direction intersecting the deflection direction of the beam by the movable reflection member. Scanning optics in which a rereflection optical system including a first optical member to be converged and a third reflected beam in which the second reflected beam is re-reflected by the movable reflecting member are incident and emitted toward the irradiated body. Arranged in the optical path between the system and the movable reflective member and the scanning optical system, the beam from the light source device is guided so as to first enter the movable reflective member, and the movable reflective member again guides the beam. It includes a light separating member that guides the reflected third reflected beam so as to enter the scanning optical system.

A second aspect of the present invention is to irradiate each of a plurality of reflecting surfaces of a rotating multifaceted mirror rotating around a rotation axis with a beam from a light source device, and scan the beam deflected by each of the reflecting surfaces for scanning. A beam scanning device that projects onto an irradiated object via an optical system and scans one-dimensionally, in which the beam from the light source device is incident and is not orthogonal to the direction of rotation on the reflecting surface of the rotating multifaceted mirror. The first cylindrical lens that converges and irradiates with respect to the deflection direction and the first reflected beam that is first reflected by the reflecting surface of the rotating multifaceted mirror are incident and reflected toward the reflecting surface of the rotating polymorphic mirror. A rereflection optical system including a second cylindrical lens that generates a second reflected beam and converges the second reflected beam on the reflecting surface of the rotating multifaceted mirror with respect to the non-deflection direction, and the rotating multifaceted mirror. Arranged in the optical path between the scanning optical system and the scanning optical system, the beam from the light source device is guided so as to first enter the reflecting surface of the rotating multifaceted mirror, and the second reflected beam is directed to the rotating polyplane. A light separating member for guiding a third reflected beam re-reflected by the reflecting surface of the mirror so as to enter the scanning optical system is provided.

A third aspect of the present invention is a pattern drawing apparatus, in a state where the substrate was moved to a predetermined direction, using the beam scanning apparatus of the first or second aspect of the present invention, the the third reflected beam from the scanning optical system projects the on the substrate as an object to be irradiated, and, by scanning the third reflected beam in the main run査direction crossing the non-deflection direction The pattern is drawn on the substrate with.

It is a figure which shows the schematic structure of the device manufacturing system which includes the exposure apparatus which performs the exposure process on the substrate of 1st Embodiment. It is a detailed view which shows the state which the substrate is wound around the rotary drum shown in FIG. It is a figure which shows the drawing line of the spot light scanned on the substrate, and the mark for alignment formed on the substrate. It is a schematic block diagram of the beam switching part shown in FIG. It is a figure which shows the specific structure around the selection optical element and the incident mirror shown in FIG. It is a perspective view which shows the structure of the scanning unit shown in FIG. It is a figure when the scanning unit shown in FIG. 6 is seen from the + Y direction. The reflection angle of the beam when it is reflected twice by the reflection surface of the polygon mirror PM shown in FIG. 6 will be described. It is a figure explaining the rotation angle of the polygon mirror required for one scan. It is a figure which shows the electrical structure of the exposure apparatus shown in FIG. It is a figure which shows the structure of the scanning unit in the modification 1 of the 1st Embodiment. FIG. 5 is a configuration diagram for reflecting a beam twice on a reflecting surface of a polygon mirror in the second modification of the first embodiment. FIG. 13A is a view when the configuration of the scanning unit of the second embodiment is viewed from the −Y direction, and FIG. 13B is a diagram when the configuration of the scanning unit of the second embodiment is viewed from the + Z direction. .. It is a figure which shows the arrangement example of the scanning unit in the modification 1 of the 2nd Embodiment. FIG. 3 is a configuration diagram for reflecting a drawing beam on a polygon mirror twice in the third embodiment. FIG. 5 is a configuration diagram for reflecting a beam on a polygon mirror twice in the first modification of the third embodiment. It is a figure which shows the structure of the scanning unit in the modification of 1st to 3rd Embodiment.

The beam scanning apparatus and 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 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 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 continuously applied and then wound up by a recovery roll (not shown). Therefore, the substrate P after various treatments is in a state in which a plurality of devices are connected in the transport direction of the substrate P, and is a substrate for multi-chamfering. The substrate P sent from the supply roll is sequentially subjected to various treatments by the process apparatus PR1, the exposure apparatus EX, and the process apparatus PR2, and is wound up by the recovery roll. 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 present embodiment, the X direction is a direction in which the substrate P is directed from the supply roll to the recovery roll in a horizontal plane orthogonal to the Z direction, and is a long direction (longitudinal direction) of the substrate P. The Y direction is a direction orthogonal to the X direction in a horizontal plane orthogonal to the Z direction, and is a width direction (short direction) of the substrate P. The −Z direction is the direction in which gravity acts (gravity direction), and the transport direction of the substrate P is the + X direction.

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 or more 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 the base material of the substrate P, a film having a thickness of 10 μm to 200 μm or less, 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 in the device manufacturing system 10, 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 or about 35 μm manufactured by a float method or the like, and the above resin film, foil or the like is attached to the ultrathin glass. It may be a combined laminate.

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 present embodiment, the substrate P buckles and folds. It can be said that the range of flexibility is such that the substrate P can be smoothly conveyed without being damaged or damaged (tear or cracked).

The process apparatus (processing apparatus) PR1 conveys the substrate P sent from the supply roll toward the exposure apparatus EX at a predetermined speed in the conveying direction (+ X direction) along the elongated direction, and transfers the substrate P to the exposure apparatus EX. The process of the previous step is performed on the substrate P to be sent. The substrate P sent to the exposure apparatus EX by the process of this previous step is a substrate (photosensitive substrate) having a photosensitive functional layer (photosensitive layer) formed on its surface.

This photosensitive functional layer is applied as a solution on the substrate P and dried to form a layer (film). A typical photosensitive functional layer is a photoresist (liquid or dry film), but as a material that does not require development treatment, the photosensitive functional layer is modified in terms of the liquid-repellent property of the portion irradiated with ultraviolet rays. There are a silane coupling agent (SAM), a photosensitive reducing agent in which a plating reducing group is exposed on a portion irradiated with ultraviolet rays, and the like. When a photosensitive silane coupling agent is used as the photosensitive functional 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 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 (processing apparatus) EX performs exposure processing on the substrate P while conveying the substrate P conveyed from the process apparatus PR1 toward the process apparatus PR2 at a predetermined speed in the conveying direction (+ X direction). It is a processing device. In the exposure apparatus EX, light corresponding to a pattern for an electronic device (for example, a pattern of a TFT electrode or wiring constituting the electronic device) is applied to the surface of the substrate P (the surface of the photosensitive functional layer, that is, the photosensitive surface). Irradiate the pattern. As a result, a latent image (modified portion) corresponding to the pattern is formed on the photosensitive functional layer.

In the present 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 exposure apparatus (pattern drawing apparatus). The exposure apparatus EX transmits the spot light SP of the pulsed beam LB (pulse beam) for exposure while transporting the substrate P in the + X direction (predetermined direction, sub-scanning direction) to the irradiated surface (photosensitive) of the substrate P. While scanning (main scanning) one-dimensionally in a predetermined scanning direction (Y direction) on the surface), the intensity of the spot light SP is modulated (on / off) at high speed according to the pattern data (drawing data, pattern information). To do. 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, the spot light SP is relatively two-dimensionally scanned on the irradiated surface (the surface of the photosensitive functional layer) of the substrate P by the sub-scanning of the substrate P and the main scanning of the spot light SP, and the spot light SP is scanned on the substrate P. A predetermined pattern is drawn and exposed on the irradiated surface. Further, since the substrate P is conveyed along the conveying direction (+ X direction), the exposure regions W where the pattern is exposed by the exposure apparatus EX are spaced apart from each other along the elongated direction of the substrate P. A plurality of them will be provided (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 process device (processing device) PR2 is the exposure device EX while transporting the substrate P sent from the exposure device EX toward the recovery roll at a predetermined speed in the transport direction (+ X direction) along the long direction. A post-process (for example, plating treatment or development / etching treatment) is performed on the exposed substrate P. The pattern layer of the device is formed on the substrate P by the processing in the subsequent step.

Next, the exposure apparatus EX will be described in more detail. The exposure apparatus EX is housed 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. Suppresses static electricity charging. The temperature control chamber ECV is arranged on the installation surface E of the manufacturing plant via the passive or active vibration isolation units SU1 and SU2. The vibration isolation units SU1 and SU2 reduce vibration from the installation surface E. The installation 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 14, a beam switching unit BDU, a drawing head 16, a control device 18, and a plurality of alignment microscopes AMm (m = 1, 2, 3, 4). , A plurality of encoder heads ENja and ENjb (note that j = 1, 2, 3) are provided at least. The control device 18 controls each part of the exposure device EX. The control device 18 includes a computer and a recording medium or the like on which the program is recorded, and when the computer executes the program, the control device 18 functions as the control device 18 of the present embodiment.

The substrate transfer mechanism 12 constitutes a part of the substrate transfer device of the device manufacturing system 10. After the substrate P transported from the process device PR1 is transported at a predetermined speed in the exposure device EX, the process device It is sent to PR2 at a predetermined speed. The substrate transfer mechanism 12 includes an edge position controller EPC, a drive roller R1, a tension adjustment roller RT1, a rotary drum (cylindrical drum) DR, and a tension adjustment roller RT2 in order from the upstream side (−X direction side) of the substrate P in the transfer direction. It has a drive roller R2 and a drive roller R3. The substrate P is transported in the exposure apparatus EX by being hung on the edge position controller EPC of the substrate transport mechanism 12, the drive rollers R1 to R3, the tension adjusting rollers RT1 and RT2, and the rotary drum (cylindrical drum) DR. The transport path of the substrate P is defined.

The edge position controller EPC adjusts the position of the substrate P conveyed from the process apparatus PR1 in the width direction (Y direction and the short direction of the substrate P). That is, in the edge position controller EPC, the position at the end (edge) in the width direction of the substrate P, which is conveyed under a predetermined tension, is about ± 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 fall within the range (allowable range) of, and the position of the substrate P in the width direction is adjusted. The edge position controller EPC is an edge sensor (edge detection unit) (not shown) that detects the position of the roller on which the substrate P is hung under a predetermined tension and the end portion (edge) of the substrate P in the width direction. And have. The edge position controller EPC moves the roller of the edge position controller EPC in the Y direction based on the detection signal detected by the edge sensor, and adjusts the position of the substrate 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 intersecting the Z 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 drawing head 16 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 surface 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 rotary drum DR rotates at a constant rotational speed around the central axis AXo by applying a rotational torque from a rotational drive source (for example, a motor, a reduction mechanism, etc.) controlled by the control device 18 to the shaft Sft. .. 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 process apparatus 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 18 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 14 generates and emits a pulsed beam (pulse beam, pulsed light, laser) LB. This beam LB is ultraviolet light having a peak wavelength 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 by the light source device 14 is incident on the drawing head 16 via the beam switching unit BDU. The light source device 14 emits and emits a beam LB at a light emission frequency Fa according to the control of the control device 18. The light source device 14 includes a semiconductor laser device that generates pulsed light in the infrared wavelength region, a fiber amplifier, and a wavelength conversion element (harmonic) that converts the amplified pulsed light in the infrared wavelength region into pulsed light in the ultraviolet wavelength region. It may be composed of a wave generating element) or the like. By configuring the light source device 14 in this way, it is possible to obtain high-intensity ultraviolet pulsed light having an oscillation frequency Fa of several hundred MHz and a light emission time of one pulsed light of about picoseconds. The beam LB emitted by the light source device 14 is a parallel light beam. In the first embodiment, as the light source device 14, a light source device as shown in Japanese Patent Application Laid-Open No. 2015-210437 (see FIG. 17) is adopted. Further, the beam LB emitted by the light source device 14 is P-polarized light which is linearly polarized light.

The beam switching unit BDU causes the beam LB to be incident on any one of the plurality of scanning units Un (note that n = 1, 2, ..., 6) constituting the drawing head 16. The scanning unit Un on which the beam LB is incident is switched. Further, the beam switching unit BDU sequentially switches the scanning units Un on which the beam LB is incident in the scanning units U1 to U6. That is, the beam LB (LBn) is distributed to each scanning unit Un by time division. For example, the beam switching unit BDU switches the scanning unit Un on which the beam LB is incident in the order of U1 → U2 → U3 → U4 → U5 → U6. The beam LB from the light source device 14 incident on the scanning unit Un via the beam switching unit BDU may be referred to as LBn. Then, the beam LBn incident on the scanning unit U1 may be represented by LB1, and similarly, the beam LBn incident on the scanning units U2 to U6 may be represented by LB2 to LB6.

The beam switching unit BDU switches the scanning unit Un on which the beam LBn is incident so that the beam LB is incident on the scanning unit Un that scans the spot light SP. The scanning unit Un that scans the spot light SP is switched in the order of U1 → U2 → U3 → U4 → U5 → U6.

The drawing head 16 is a so-called multi-scan type drawing head in which a plurality of scanning units Un (U1 to U6) having the same configuration are arranged. The drawing head 16 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). Each scanning unit Un (U1 to U6) focuses (converges) the beam LBn on the substrate P while projecting the beam LBn from the beam switching unit BDU onto the substrate P (on the irradiated surface of the substrate P). .. As a result, the beam LBn (LB1 to LB6) projected on the substrate P becomes the spot light SP. Further, each scanning unit Un (U1 to U6) has a polygon mirror PM, and the rotated polygon mirror PM is used to mainly scan the spot light SP of the beam LBn (LB1 to LB6) projected on the substrate P. Scan in the direction (Y direction). By scanning the spot light SP, a linear drawing line (scanning line) SLn (n = 1, 2, ..., 6) in which a pattern for one line is drawn is defined on the substrate P. To. That is, the drawing line SLn shows the scanning locus of the spot light SP of the beam LBn on the substrate P.

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 SLn (SL1 to SL6) of the plurality of scanning units Un (U1 to U6) are formed on the rotating drum DR with the central surface Poc (see FIGS. 1 and 3) interposed therebetween. They are arranged in a staggered arrangement in two rows in the circumferential direction. 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, and are along the Y direction. They are arranged in a row with a predetermined interval. 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, and along the Y direction. They are arranged in a row with a predetermined interval.

Therefore, the plurality of scanning units Un (U1 to U6) are also arranged in a staggered arrangement in two rows in the transport direction of the substrate P with the central surface Poc interposed therebetween (see FIG. 2). That is, the odd-numbered scanning units U1, U3, and U5 are 1 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. Arranged in a row. 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 from the XZ plane.

In the X direction, the odd-numbered drawing lines SL1, SL3, SL5 and the even-numbered drawing lines SL2, SL4, SL6 are separated from each other, but in the Y direction (width direction of the substrate P, main scanning direction). It is set to be spliced together without being separated from each other. The drawing lines SL1 to SL6 are substantially parallel to the width direction (Y direction) of the substrate P, that is, the central axis AXo of the rotating drum DR. In addition, joining the drawing lines SLn in the Y direction means that the ends of the patterns drawn in each of the drawing lines SLn are adjacent to each other or partially overlapped with respect to the Y direction. When the ends of the patterns drawn on each of the drawing lines SLn are overlapped, for example, a few percent or less in the Y direction including the drawing start point or the drawing end point with respect to the length of each drawing line SLn. It is good to overlap within the range of.

As described above, each scanning unit Un (U1 to U6) shares the scanning region so that the plurality of scanning units Un (U1 to U6) cover the entire width direction of the exposure region W in total. As a result, each scanning unit Un (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 length (drawing range length) of each drawing line SLn (SL1 to SL6) is 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.

In the case of the present embodiment, since the beam LB from the light source device 14 is pulsed light, the spot light SP projected on the drawing line SLn during the main scan has an oscillation frequency Fa (for example, 100 MHz) of the beam LB. It becomes discrete according to. Therefore, it is necessary to overlap the spot light SP projected by the one-pulse light of the beam LB and the spot light SP projected by the next one-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 present 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. 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 the rotation speed of the rotating drum DR so that the rotating drum DR moves in the circumferential direction by a distance of about 1/2 of a large size φ. Further, when the drawing lines SLn adjacent to each other in the Y direction are connected in the main scanning direction, it is desirable to overlap by φ / 2. In the present embodiment, the size (dimension) φ of the spot light SP is 3 μm.

Each scanning unit Un (U1 to U6) projects 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. At this time, the optical axes (central axes) of the beams LB1, LB3, and LB5 projected from the odd-numbered scanning units U1, U3, and U5 toward the substrate P are in the same direction in the XZ plane, and the directions described later. It overlaps the line Lx2 (see FIG. 1). Further, the optical axes (central axes) of the beams LB2, LB4, and LB6 projected from the even-numbered scanning units U2, U4, and U6 toward the substrate P are in the same direction in the XZ plane, and are directional lines described later. It overlaps with Lx3 (see FIG. 1). The directional line Lx2 and the directional line Lx3 are set so that the angle with respect to the central plane Poc is ± θ1 in the XZ plane (see FIG. 1). That is, with respect to the XZ plane, the traveling direction of the beam LB projected from the odd-numbered scanning units U1, U3, U5 toward the substrate P and the even-numbered scanning units U2, U4, U6 are projected toward the substrate P. The traveling direction of the beam is symmetrical with respect to the central plane Poc. 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.

The plurality of alignment microscopes AMm (AM1 to AM4) shown in FIG. 1 are for detecting a plurality of alignment marks MKm (MK1 to MK4) formed on the substrate P shown in FIG. 3 in the Y direction. (4 in the first embodiment) are provided along the above. The plurality of 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. .. The plurality of alignment microscopes AMm (AM1 to AM4) detect a plurality of marks MKm (MK1 to MK4) on the substrate P supported by the outer peripheral surface (circumferential surface) of the rotating drum DR. The plurality of alignment microscopes AMm (AM1 to AM4) 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 drawing head 16. It is provided on the upstream side (−X direction side) of the substrate P in the transport direction.

The alignment microscope AMm (AM1 to AM4) obtains a light source that projects illumination light for alignment onto the substrate P and a magnified image of a local region (observation region) Vwm (Vw1 to Vw4) including the mark MKm on the surface of the substrate P. An observation optical system (including an objective lens) and an image sensor such as a CCD or CMOS that captures an enlarged image of the magnified image with a high-speed shutter according to the transport speed Vt of the substrate P while the substrate P is moving in the transport direction. Has. The image pickup signals (image data) captured by each of the plurality of alignment microscopes AMm (AM1 to AM4) are sent to the control device 18. The control device 18 detects the position (mark position information) of the marks MKm (MK1 to MK4) on the substrate P by performing image analysis of the plurality of transmitted 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 marks MK1 to MK4 are provided around each exposure region W. A plurality of marks MK1 and MK4 are formed on both sides of the substrate P in the exposure region W in the width direction at regular intervals Dh along the longitudinal direction of the substrate P. The mark MK1 is formed on the −Y direction side in the width direction of the substrate P, and the mark MK4 is formed on the + Y direction side in the width direction of the substrate P. Such marks MK1 and MK4 are arranged so as to be in the same position in the long direction (X direction) of the substrate P when the substrate P is not deformed due to a large tension or a thermal process. Will be done. Further, the marks MK2 and MK3 are formed between the mark MK1 and the mark MK4 in the margins between the + X direction side and the −X direction side of the exposure region W along the width direction (short direction) of the substrate P. ing. The mark MK2 is formed on the −Y direction side in the width direction of the substrate P, and the mark MK3 is formed on the + Y direction side of the substrate P.

Further, the distance between the mark MK1 arranged at the end on the −Y direction side of the substrate P and the mark MK2 in the margin portion in the Y direction, the distance between the mark MK2 and the mark MK3 in the margin portion in the Y direction, and the + Y of the substrate P. The distance between the mark MK4 arranged at the end on the direction side and the mark MK3 in the margin in the Y direction is set to the same distance. These marks MKm (MK1 to MK4) may be formed together at the time of forming the pattern layer of the first layer. For example, when the pattern of the first layer is exposed, the pattern for the mark MKm may also be exposed around the exposure region W where the pattern is exposed. The 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 mark MKm.

As shown in FIG. 3, the alignment microscope AM1 is arranged so as to image the mark MK1 existing in the observation region (detection region) Vw1 by the objective lens. Similarly, the alignment microscopes AM2 to AM4 are arranged so as to image the marks MK2 to MK4 existing in the observation areas Vw2 to Vw4 by the objective lens. Therefore, the plurality of alignment microscopes AM1 to AM4 are provided along the width direction of the substrate P in the order of AM1 to AM4 from the −Y direction side of the substrate P corresponding to the positions of the plurality of marks MK1 to MK4. ..

In the plurality of alignment microscopes AMm (AM1 to AM4), the distance between the exposure position (drawing lines SL1 to SL6) and the observation area Vwm (Vw1 to Vw4) in the X direction is shorter than the length of the exposure area W in the X direction. It is provided so as to be. The number of alignment microscopes AMm provided in the Y direction can be changed according to the number of marks MKm formed in the width direction of the substrate P. The size of the substrate P in each observation area Vwm (Vw1 to Vw4) on the irradiated surface is set according to the size of the marks MK1 to MK4 and the alignment accuracy (position measurement accuracy), but is 100 to 500 μm square. It is about the size.

In the first embodiment, the drawing lines SL1, SL3, SL5 of the odd-numbered scanning units U1, U3, U5 and the drawing lines SL2 of the even-numbered scanning units U2, U4, U6 in the X direction. Since the positions of SL4 and SL6 on the substrate P are close to each other, a plurality of alignment microscopes AM (AM1 to AM4) are arranged on the upstream side of the drawing lines SL1, SL3, and SL5. However, the positions of the odd-numbered scanning units U1, U3, and U5 on the substrate P with the drawing lines SL1, SL3, and SL5 and the even-numbered scanning units U2, U4, and U6 on the substrate P are in the circumferential direction. When the distance is more than a predetermined distance, it corresponds to the odd-numbered scanning units U1, U3, U5 and the even-numbered scanning units U2, U4, U6 arranged along the X direction (conveying direction of the substrate P). , A plurality of alignment microscopes AMm (AM1 to AM4) may be provided respectively. That is, a plurality of alignment microscopes AM (AM1 to AM4) are provided in a row along the Y direction at the same position on the upstream side of the odd-numbered drawing lines SL1, SL3, and SL5 in the X direction, and are even numbers in the X direction. A plurality of alignment microscopes AM (AM1 to AM4) are provided in a row along the Y direction at the same position on the downstream side of the drawing lines SL1, SL3, SL5 and on the upstream side of the drawing lines SL2, SL4, SL6. ..

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 EN1a to EN3a and EN1b to EN3b as scale reading heads for reading the scale units SDa and SDb are provided so as to face the scale units SDa and SDb (see FIGS. 1 and 2).

The encoder heads ENja and ENjb project a measurement beam onto each of the scale units SDa and SDb to optically detect the rotation angle position of the rotating drum DR. Three encoder heads ENja (EN1a, EN2a, EN3a) are provided so as to face the scale portion SDa provided at the end on the −Y direction side of the rotary drum DR. Similarly, three encoder heads ENjb (EN1b, EN2b, EN3b) 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 encoder heads 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 azimuth line Lx1 (see FIGS. 1 and 2). .. The azimuth line Lx1 is a line connecting the projection positions (reading positions) of the optical beams for measurement of the encoder heads EN1a and EN1b on the scale portions SDa and SDb and the central axis AXo in the XZ plane. Further, the directional line Lx1 is a line connecting the observation regions Vwm (Vw1 to Vw4) of each alignment microscope AMm (AM1 to AM4) and the central axis AXo in the XZ plane. That is, a plurality of alignment microscopes AMm (AM1 to AM4) are also arranged on the directional line Lx1.

The encoder heads 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 encoder heads EN1a and EN1b in the transport direction of the substrate P (. It is provided on the + X direction side). The encoder heads EN2a and EN2b are arranged on the directional line Lx2 (see FIGS. 1 and 2). The directional line Lx2 is a line connecting the projection positions (reading positions) of the optical beams for measurement of the encoder heads EN2a and EN2b on the scale portions SDa and SDb and the central axis AXo in the XZ plane.

The encoder heads 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 azimuth line Lx3 (see FIGS. 1 and 2). The directional line Lx3 is a line connecting the projection positions (reading positions) of the optical beams for measurement of the encoder heads EN3a and EN3b on the scale portions SDa and SDb and the central axis AXo in the XZ plane.

When a plurality of alignment microscopes AMm (AM1 to AM4) are arranged in a row along the Y direction corresponding to even-numbered scanning units U2, U4, and U6, a plurality of alignment microscopes AMm (AM1 to AM4) are arranged. ) Is installed separately on the azimuth line Lx4 to provide the encoder heads EN4a and EN4b. In this case, the alignment microscopes AMm (AM1 to AM4) and the encoder heads EN4a and EN4b are installed between the odd-numbered scanning units U1, U3 and U5 and the even-numbered scanning units U2, U4 and U6. Needless to say, the directional line Lx4 is a line passing through the central axis AXo.

The encoder heads ENja (EN1a to EN3a) and ENjb (EN1b to EN3b) project an optical beam for measurement toward the scale units SDa and SDb, and receive a pulsed light beam (diffracted light) by photoelectric detection. A detection signal (two-phase signal), which is a signal, is output to the control device 18. The control device 18 interpolates the detection signals (two-phase signals) of the encoder heads ENja (EN1a to EN3a) and counts the amount of movement of the grids of the scale units SDa and SDb with a digital counter. The rotation angle position and angle change of the are measured with submicron resolution. The transport speed Vt of the substrate P can also be measured from the angle change of the rotating drum DR, that is, the frequency (or period) of the pulse signal counted by the digital counter.

Either one of the digital count values based on the detection signals (two-phase signal) from each of the encoder heads EN1a and EN1b or the average value thereof is used as the rotation angle position of the rotation drum DR seen from above the directional line Lx1. Similarly, either one or the average value of the digital count values based on the encoder heads EN2a and EN2b is used as the rotation angle position of the rotary drum DR as viewed from the azimuth line Lx2, and the digital count values based on the encoder heads EN3a and EN3b are used. Either one of the count values or the average value is used as the rotation angle position of the rotation drum DR as viewed from the azimuth line Lx3. In principle, the digital count values based on the encoder heads EN1a and EN1b are the same, except when the rotary drum DR is eccentrically rotating with respect to the central axis AXo due to a manufacturing error of the rotary drum DR or the like. Similarly, the digital count values based on the encoder heads EN2a and EN2b are also the same, and the digital count values based on the encoder heads EN3a and EN3b are also the same.

By using the alignment system composed of the plurality of alignment microscopes AMm (AM1 to AM4), the scale units SDa and SDb, and the plurality of encoder heads ENja (EN1a to EN3a) and ENjb (EN1b to EN3b), the substrate P The transport state (whether or not it is distorted), the position of the exposure region W, the position of the drawing lines SL1 to SL6 on the substrate P, and the like can be grasped with high accuracy. As described above, regarding the configuration in which the plurality of encoder heads ENja (EN1a to EN3a) and ENjb (EN1b to EN3b) are arranged around the scale portions SDa and SDb formed in an annular shape along the cylindrical surface, for example, internationally. It is disclosed in Publication No. 2013/146184.

Next, the configuration of the beam switching unit BDU will be briefly described with reference to FIG. The beam switching unit BDU includes, for example, a plurality of selection optical elements AOMn (AOM1 to AOM6), a plurality of reflection mirrors M1 to M3, and a plurality of beam switching units BDU, as described in detail in the pamphlet of International Publication No. 2015/166910. It has an incident mirror Imn (IM1 to IM6) and an absorber TR. The selective optical elements AOMn (AOM1 to AOM6) are acousto-optic modulators (AOMs) that have transparency with respect to the beam LB and are driven by ultrasonic signals. The plurality of selection optical elements AOMn (AOM1 to AOM6) and the plurality of incident mirrors Imn (IM1 to IM6) are provided corresponding to the plurality of scanning units Un (U1 to U6). For example, the selection optical elements AOM1 and the incident mirror IM1 are provided corresponding to the scanning unit U1, and similarly, the selection optical elements AOM2 to AOM6 and the incident mirrors IM2 to IM6 correspond to the scanning units U2 to U6, respectively. It is provided.

The optical path of the beam LB from the light source device 14 is bent by the reflection mirrors M1 to M3 and guided to the absorber TR. Hereinafter, the case where all of the selection optical elements AOMn (AOM1 to AOM6) are in the off state (the state in which the ultrasonic signal is not applied) will be described in detail.

The beam LB from the light source device 14 travels in the + X direction in parallel with the X axis and is incident on the reflection mirror M1. The beam LB reflected in the + Y direction by the reflection mirror M1 passes straight through the selection optical elements AOM1, AOM3, and AOM5 in the above order, and then reaches the reflection mirror M2. The beam LB reflected in the + X direction by the reflection mirror M2 is incident on the reflection mirror M3. The beam LB reflected in the −Y direction by the reflection mirror M3 passes straight through the selection optical elements AOM2, AOM4, and AOM6 in the above order, and then is guided to the absorber TR. The absorber TR is an optical trap that absorbs the beam LB in order to suppress leakage of the beam LB to the outside.

When an ultrasonic signal (high frequency signal) is applied, each selection optical element AOMn emits first-order diffracted light obtained by diffracting an incident beam (0th-order light) LB at a diffraction angle corresponding to a high-frequency frequency. It is generated as (beam LBn). Therefore, the beam emitted from the selection optical element AOM1 as the primary diffracted light becomes LB1, and similarly, the beam emitted from the selective optical element AOM2 to AOM6 as the primary diffracted light becomes LB2 to LB6. As described above, each selection optical element AOMn (AOM1 to AOM6) functions to deflect the optical path of the beam LB from the light source device 14. However, since the generation efficiency of the first-order diffracted light is about 80% of the 0th-order light in the actual acoustic-optical modulation element, the beam LBn (LB1 to LB1) deflected by each of the selection optical elements AOMn (AOM1 to AOM6). LB6) is lower than the intensity of the original beam LB. Further, when any one of the selection optical elements AOMn (AOM1 to AOM6) is in the ON state, about 20% of the 0th-order light that travels straight without being diffracted remains, which is finally absorbed by the absorber TR. ..

The beam LBn (LB1 to LB6), which is the primary diffracted light deflected by the selection optical elements AOMn (AOM1 to AOM6), is projected onto the corresponding incident mirrors Imn (IM1 to IM6). The incident mirror Imn (IM1 to IM6) is a light guide member that guides the incident beam LBn (LB1 to LB6) to the corresponding scanning units Un (U1 to U6). For example, the beam LB1 deflected by the selection optical element AOM1 is guided to the scanning unit U1 after being incident on the incident mirror IM1.

The optical elements AOMn (AOM1 to AOM6) for selection may have the same configuration, function, action, and the like. The plurality of selection optical elements AOMn (AOM1 to AOM6) turn on / off the generation of diffracted light diffracting the incident beam LB according to the on / off of the drive signal (high frequency signal) from the control device 18. For example, the selection optical element AOM1 transmits the beam LB from the incident light source device 14 without diffracting it when the drive signal (high frequency signal) from the control device 18 is not applied and is in the off state. Therefore, the beam LB transmitted through the selection optical element AOM1 is incident on the selection optical element AOM3. On the other hand, when the drive signal (high frequency signal) from the control device 18 is applied and the selection optical element AOM1 is in the ON state, the incident beam LB is diffracted and directed toward the incident mirror IM1. That is, the selection optical element AOM1 is switched on by this drive signal. In this way, by switching on any one of the plurality of selection optical elements AOMn (AOM1 to AOM6), the beam LBn can be guided to any one scanning unit Un, and The scanning unit Un on which the beam LBn is incident can be switched. In the first embodiment, the scanning unit Un on which the beam LBn is incident is switched in the order of U1 → U2 → U3 → U4 → U5 → U6, so that the selection optical element AOMm that switches on is changed from AOM1 →. It may be switched in the order of AOM2 → AOM3 → AOM4 → AOM5 → AOM6. In the example shown in FIG. 4, the selection optical element AOM6 is switched on and the beam LB6 is incident on the scanning unit U6.

FIG. 5 is a diagram showing a specific configuration around the selection optical element AOMn and the incident mirror Imn. As a general rule, since the configurations around the selection optical element AOMn and the incident mirror Imn are the same, only the configurations around the selection optical element AOM1 and the incident mirror IM1 will be described.

A parallel light beam beam LB having a minute diameter (first diameter) of, for example, about 1 mm is incident on the selection optical element AOM1. When the drive signal, which is a high-frequency signal (ultrasonic signal), is not input (the drive signal is off), the selection optical element AOM1 transmits the incident beam LB as it is without diffracting it. The transmitted beam LB passes through the condenser lens G1 and the collimating lens G2a provided on the optical path, and is incident on the selection optical element AOM3 in the subsequent stage. At this time, the optical axis (central axis) of the beam LB passing through the condenser lens G1 and the collimating lens G2a through the selection optical element AOM1 is defined as AXa. The condenser lens G1 focuses the beam LB transmitted through the selection optical element AOM1 at the rear focal point located between the condenser lens G1 and the collimating lens G2a. The collimating lens G2a converts the diverged beam LB into a parallel luminous flux after being focused by the condenser lens G1. The diameter of the beam LB made into a parallel luminous flux by the collimating lens G2a is the first diameter. The rear focal point of the condenser lens G1 and the anterior focal point of the collimating lens G2a coincide with each other within a predetermined allowable range. The condenser lens G1 and the collimating lens G2a form a relay lens system having the same magnification. Further, the front focal point of the condenser lens G1 and the deflection position by the selection optical element AOM1 coincide with each other within a predetermined allowable range. In FIG. 5, the distance of the front focal point of the condenser lens G1 is represented by fa, and the distance of the rear focal point is represented by fb.

On the other hand, when a drive signal which is a high frequency signal is input, the selection optical element AOM1 generates a beam LB1 (primary diffracted light) in which the incident beam LB is deflected by a diffraction angle corresponding to the frequency of the high frequency signal. To do. The beam LB1 deflected in the −Z direction at a diffraction angle corresponding to the frequency of the high-frequency signal passes through the condensing lens G1 and is provided at the position of the rear focal point of the condensing lens G1 or a position in the vicinity thereof. It is incident on the mirror (also called an epi-illumination mirror because the beam is epi-illuminated in the −Z direction) IM1. The condenser lens G1 bends the beam LB1 so that the optical axis (central axis) AXb of the beam LB1 deflected in the −Z direction is parallel to the optical axis AXa of the beam LB, and makes the beam LB1 of the incident mirror IM1. Condenses (converges) on or near the reflective surface. The beam LB1 reflected in the −Z direction by the incident mirror IM1 provided on the −Z direction side with respect to the beam LB transmitted through the selection optical element AOM1 is incident on the scanning unit U6 via the collimating lens G2b. The collimating lens G2b makes the diverged beam LB1 a parallel light flux having the same diameter as the first diameter after being focused by the condenser lens G1. The rear focal point of the condenser lens G1 and the anterior focal point of the collimating lens G2b coincide with each other within a predetermined allowable range. The condenser lens G1 and the collimating lens G2b form a relay lens system having the same magnification.

Next, the configuration of the scanning unit (beam scanning device) Un will be described with reference to FIGS. 6 and 7. Since each scanning unit Un (U1 to U6) has the same configuration, only the scanning unit U1 will be briefly described. FIG. 6 is a perspective view showing the configuration of the scanning unit U1, and FIG. 7 is a view when the scanning unit U1 shown in FIG. 6 is viewed from the + Y direction. The scanning unit U1 includes a cylindrical lens CY1, a polarizing beam splitter PBS, a λ / 4 wave plate QP, a polygon mirror (movable reflection member) PM, a cylindrical lens CY2, a reflection mirror M10, an fθ lens FT, a reflection mirror M11, and a cylindrical lens. It is equipped with CY3.

The beam LB1 of the parallel luminous flux reflected by the incident mirror (light guide member) IM1 shown in FIG. 5 in the −Z direction was enlarged beyond the first diameter (for example, about 1 mm) by a beam expander optical system (not shown). After being converted into a parallel light flux having a predetermined diameter (for example, several mm), it is incident on the scanning unit U1 along the optical axis AX1 parallel to the Z axis. The beam LB1 incident on the scanning unit U1 (hereinafter, may be referred to as an incident beam LB1a) is a polarizing beam through a cylindrical lens (second optical member) CY1 provided on the optical axis AX1 and having a generatrix in the Y direction. It is incident on the splitter PBS. The polarization separation surface Qs of the polarization beam splitter PBS is tilted 45 degrees with respect to the XY plane, transmits P-polarized light, and reflects linearly polarized (S-polarized) light polarized in a direction orthogonal to P-polarized light. It is a thing. Since the beam LB emitted by the light source device 14 is P-polarized, the light incident on the polarizing beam splitter PBS through the cylindrical lens CY1 passes through the polarizing beam splitter PBS along the optical axis AX1 and of the polarizing beam splitter PBS. After passing through the λ / 4 wave plate QP provided on the −Z direction side, the light is guided to the reflecting surface RP of the polygon mirror PM. The polarizing beam splitter PBS and the λ / 4 wave plate QP constitute an optical splitting member (optical separating member) .

The polygon mirror PM has a rotation axis AXp and a plurality of reflection surface RPs formed around the rotation axis AXp in parallel with the rotation axis AXp (in the first embodiment, the number Np of the reflection surface RPs is 8). It is a rotating multifaceted mirror having In the polygon mirror PM, the incident beam LB1a incident on the reflection surface RP of the polygon mirror PM from the polarizing beam splitter PBS is reflected toward the reflection mirror M10 provided at the position on the −X direction side of the polygon mirror PM. , The plane orthogonal to the rotation axis AXp is arranged so as to be tilted 45 degrees with respect to the XY plane. The polygon mirror PM rotates about the rotation axis AXp in order to scan the spot light SP of the beam LB1 on the irradiated surface of the substrate P. By rotating this polygon mirror PM around the rotation axis AXp in a predetermined rotation direction, the reflection angle of the pulsed beam LB1a irradiated on the reflection surface RP can be continuously changed. As a result, 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 scanned along the main scanning direction (width direction of the substrate P, Y direction). can do. Therefore, the number of times the spot light SP is scanned along the drawing line SL1 on the irradiated surface of the substrate P by one rotation of the polygon mirror PM is eight times, which is the same as the number of the 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 or the like) RM1 (see FIG. 10) under the control of the control device 18.

The polygon mirror PM deflects the incident beam LB1a incident from the polarizing beam splitter PBS in a plane parallel to the XY plane including the optical axis AX2 set parallel to the X axis, and in the Y direction about the optical axis AX2. Bias to. A generatrix extending in the Y direction of the cylindrical lens CY1 is located on a plane on which the incident beam LB1a is polarized (a plane parallel to the XY plane). The optical axis AX2 is orthogonal to the optical axis AX1, and the plane including the optical axes AX1, AX2 and the rotation axis AXp is parallel to the XZ plane.

The cylindrical lens (second optical member) CY1 having a bus in the Y direction is incident in a non-scanning direction (Z direction or the direction of the rotation axis AXp) orthogonal to the main scanning direction (rotation direction, deflection direction) by the polygon mirror PM. The beam LB1 is converged on the reflecting surface RP of the polygon mirror PM. That is, the cylindrical lens CY1 converges the beam LB1 in a slit shape (oblong shape) extending in the Y direction on the reflection surface RP. The cylindrical lens CY1 having a generatrix in the Y direction transmits the incident incident beam LB1a as parallel light without converging in the main scanning direction (deflection direction) by the polygon mirror PM.

The reflected light of the incident beam LB1a (hereinafter, may be referred to as the first reflected beam LB1b) reflected on the −X direction side by the reflecting surface RP of the polygon mirror PM passes through the cylindrical lens (first optical member) CY2. It is incident on the reflection mirror M10. The first reflected beam LB1b reflected by the reflecting surface RP is incident on the cylindrical lens CY2 while diverging in the non-scanning direction (Z direction) orthogonal to the main scanning direction by the polygon mirror PM, but the cylindrical having a bus in the Y direction. It is made into parallel light by the lens CY2. Therefore, the first reflected beam LB1b incident on the reflection mirror M10 is a parallel light flux having substantially the same diameter as the incident beam LB1a incident on the cylindrical lens CY1. The rear focal point of the cylindrical lens CY1 and the anterior focal point of the cylindrical lens CY2 coincide with each other within a predetermined allowable range on the reflecting surface RP of the polygon mirror PM on which the incident beam LB1a is incident.

The reflection mirror M10 reflects the first reflection beam LB1b first reflected by the reflection surface RP of the polygon mirror PM toward the reflection surface RP of the polygon mirror PM again. The reflected light of the first reflected beam LB1b reflected by the reflection mirror M10 (hereinafter, may be referred to as a second reflected beam LB1c) is first incident on the reflecting surface RP reflecting the incident beam LB1a. Hereinafter, for the sake of clarity, the reflection surface RP of the polygon mirror PM to which the incident beam LB1a transmitted through the polarizing beam splitter PBS is incident is represented by RPa. Therefore, both the reflection surface RP that reflects the first reflection beam LB1b toward the reflection mirror M10 and the reflection surface RP on which the second reflection beam LB1c reflected by the reflection mirror M10 is incident are the reflection surface RPa. The second reflection beam LB1c reflected by the reflection mirror M10 passes through the cylindrical lens CY2 and is incident on the reflection surface RPa. Therefore, the second reflection beam LB1c re-incidents on the reflection surface RPa is subjected to the cylindrical lens CY2 in the non-scanning direction (Z direction or the direction of the rotation axis AXp) orthogonal to the main scanning direction (deflection direction) by the polygon mirror PM. , Converges on the reflective surface RPa. That is, the cylindrical lens CY2 converges the second reflection beam LB1c in a slit shape (oblong shape) extending in the Y direction on the reflection surface RPa. Converging position on the reflective surface RPa by the cylindrical lens CY1 and on the reflective surface RPa by the cylindrical lens CY2 with respect to the non-scanning direction (Z direction or the direction of the rotation axis AXp) orthogonal to the main scanning direction (deflection direction) by the polygon mirror PM. It is set to the same position as the convergence position of. That is, with respect to the non-scanning direction (Z direction or the direction of the rotation axis AXp) orthogonal to the main scanning direction (deflection direction) by the polygon mirror PM, the position of the incident beam LB1a first incident on the reflection surface RPa and again (second time). The position is set to be substantially the same as the position of the incident second reflected beam LB1c. Thereby, the thickness of the polygon mirror PM (the length in the rotation axis AXp direction) can be reduced. Further, even if the reflecting surface RPa is tilted with respect to the direction of the rotation axis AXp due to the cylindrical lenses CY1 and CY2 whose generatrix is parallel to the Y direction and the cylindrical lens CY3 described later, the influence thereof. Can be suppressed. For example, the irradiation position of the spot light SP (drawing line SL1) by the beam LB1 irradiated on the irradiated surface of the substrate P may be displaced in the X direction due to a slight tilt error for each reflecting surface RP of the polygon mirror PM. It can be suppressed. The reflection mirror M10 and the cylindrical lens CY2 form a rereflection optical system.

The reflection surface RPa of the polygon mirror PM reflects the second reflection beam LB1c reflected by the reflection mirror M10 toward the + Z direction side. The polygon mirror PM includes an optical axis AX1 parallel to the Z axis and deflects the second reflected beam LB1c incident from the reflection mirror M10 in a plane parallel to the YZ plane. The reflected light of the second reflected beam LB1c (hereinafter, may be referred to as the third reflected beam LB1d) re-reflected by the reflecting surface RPa of the polygon mirror PM re-enters the polarizing beam splitter PBS. Here, since the λ / 4 wave plate QP is provided between the polygon mirror PM and the polarizing beam splitter PBS, the beam LB1a that passes through the polarizing beam splitter PBS and is incident on the reflecting surface RPa of the polygon mirror PM. Is converted from P-polarized light to circularly polarized light. Further, the beam LB1d which is reflected by the reflecting surface RPa of the polygon mirror PM and re-incidents on the polarizing beam splitter PBS is converted from circularly polarized light to S-polarized light. Therefore, the third reflection beam LB1d is reflected in the + X direction by the polarization separation surface Qs of the polarization beam splitter PBS tilted 45 degrees with respect to the XY plane.

The third reflected beam LB1d reflected on the polarization separation surface Qs toward the + X direction is incident on the fθ lens FT having an optical axis AXf parallel to the X axis. The fθ lens FT makes the third reflection beam LB1d reflected by the polygon mirror PM include the optical axis AXf, and the reflection mirror M11 (finally) so as to be parallel to the optical axis AXf in a plane parallel to the XY plane. Is a telecentric scan lens that projects onto the substrate P). The fθ lens FT scans the third reflection beam LB1d projected on the reflection mirror M11 (finally the substrate P) about the optical axis AXf in the Y direction. The angle of incidence θ of the beam LB1 on the fθ lens FT changes according to the rotation angle (θ / 4) of the polygon mirror PM. The fθ lens FT projects the beam LB1 (LB1d) at the image height position on the irradiated surface of the substrate P in proportion to the incident angle θ thereof via the reflection mirror M11 and the cylindrical lens CY3. 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 scan the beam LB1 in the Y direction accurately at a constant velocity. The plane including the optical axes AX1, AX2, and AXf is parallel to the XZ plane, and when the angle of incidence θ on the fθ lens FT is 0 degrees, the main ray of the beam LB1 (LB1d) incident on the fθ lens FT is , Proceed along the optical axis AXf.

In the first embodiment, since the beam LB1 is reflected twice by the reflection surface RPa of the polygon mirror PM, the incident angle θ of the beam LB1 on the fθ lens FT is 4 of the rotation angle of the polygon mirror PM. It has doubled. However, when the beam LB1 is reflected only once on the reflection surface RPa of the polygon mirror PM, the angle of incidence θ of the beam LB1 on the fθ lens FT is twice the rotation angle of the polygon mirror PM. Therefore, the scanning speed of the spot light SP can be doubled by reflecting the beam LB1 twice on the reflecting surface RPa of the polygon mirror PM. This will be described in detail later with reference to FIG.

The second reflection beam LB1c reflected by the reflection mirror M10 and incident on the polygon mirror PM is a reflection surface by the cylindrical lens CY2 in the non-scanning direction (Z direction) orthogonal to the main scanning direction (deflection direction) by the polygon mirror PM. It is converged on RPa. Therefore, the third reflection beam LB1d reflected by the reflecting surface RPa and heading toward the fθ lens FT diverges in the non-scanning direction (Z direction) orthogonal to the main scanning direction (deflection direction) by the polygon mirror PM, while diverging from the fθ lens FT. Is incident on. On the other hand, the second reflection beam LB1c reflected by the reflection mirror M10 and incident on the polygon mirror PM is parallel light with respect to the main scanning direction (deflection direction) by the polygon mirror PM. Therefore, the third reflected beam LB1d reflected by the reflecting surface RPa and directed toward the fθ lens FT has a parallel luminous flux with respect to the main scanning direction (deflection direction) by the polygon mirror PM.

The fθ lens FT makes the third reflected beam LB1d, which is incident while diverging, substantially parallel light in the non-scanning direction (Z direction) orthogonal to the main scanning direction (deflection direction) by the polygon mirror PM. The fθ lens FT converges the third reflected beam LB1d of the incident parallel light on the substrate P with respect to the main scanning direction (deflection direction) by the polygon mirror PM. Therefore, the front focal point of the fθ lens FT is located on the reflecting surface RPa of the polygon mirror PM on which the beam LB (LB1a, LB1c) is incident, and the rear focal point is located on the substrate P. The beam LB1d transmitted through the fθ lens FT reaches the substrate P through the cylindrical lens (third optical member) CY3 having a generatrix in the Y direction after being bent by the reflection mirror M11. The reflection mirror M11 reflects the third reflection beam LB1d toward the substrate P so that the optical axis of the third reflection beam LB1d overlaps the azimuth line Lx2 with respect to the XZ plane. The cylindrical lens CY3 converges the third reflected beam LB1d of the parallel light transmitted through the fθ lens FT on the substrate P in the non-scanning direction (Z direction) orthogonal to the main scanning direction (deflection direction) by the polygon mirror PM. Therefore, the beam LB1 projected on the substrate P is converged on the spot light SP on the substrate P by the fθ lens FT and the cylindrical lens CY3. The rear focal point of the cylindrical lens CY3 is located on the substrate P. The fθ lens FT and the cylindrical lens CY3 form a scanning optical system.

In FIG. 7, the main ray of the beam LB1d (or the optical axis AXf of the fθ lens FT) reflected in the −Z direction by the reflection mirror M11 is at an angle θ1 with respect to the Z axis in a plane parallel to the XZ plane. The reflection mirror M11 and the cylindrical lens CY3 are arranged so as to be tilted. The angle θ1 corresponds to the inclination angle ± θ1 from the central surface Poc of the directional line Lx2 (or Lx3) shown in FIG. Therefore, the reflection surface (plane) of the reflection mirror M11 is arranged at an angle (45 ° −θ / 2) with respect to the XY plane. However, when each of the scanning units Un (U1 to U6) of FIGS. 6 and 7 is tilted by an angle θ1 as a whole with respect to the XY plane from the illustrated state, the reflection surface of the reflection mirror M11 is from the fθ lens FT. The main ray of the beam LB1d of No. 1 is arranged so as to intersect the optical axis AXf at 45 ° so as to be reflected at 90 ° in the XZ plane.

Next, FIG. 8 describes the reflection angle of the beam LB1 when it is reflected twice by the reflection surface RPa of the polygon mirror PM. In FIG. 8, since the optical path of the beam LB1 is schematically shown in order to make it easy to understand, the arrangement of the polygon mirror PM, the polarizing beam splitter PBS, the cylindrical lens CY2, and the reflection mirror M10 is shown in FIGS. It is slightly different from the one shown in 8.

In FIG. 8, the amount of change in the angle of the reflection surface RPa of the polygon mirror PM on which the incident beam LB1a is incident with respect to the reference surface Po is defined as Δθ. This reference plane Po includes the rotation axis AXp of the polygon mirror PM, and is a plane parallel to the plane extending in the Y direction. When the angle change amount Δθ with respect to the reference surface Po of the reflection surface RPa is 0 degrees, the incident beam LB1a incident on the reflection surface RPa of the polygon mirror PM along the optical axis AX1 is a reflection mirror along the optical axis AX2. It is incident on M10. Therefore, in this case, the second reflection beam LB1c reflected by the reflection mirror M10 is incident on the reflection surface RPa of the polygon mirror PM along the optical axis AX2, and the third reflection beam LB1d reflected there is along the optical axis AX1. It proceeds to the polarizing beam splitter PBS and then passes on the optical axis AXf of the fθ lens FT. When viewed on the optical path of the beam LB1, the optical axes AX1, AX2, and AXf are coaxial.

The first reflection beam LB1b of the incident beam LB1a transmitted through the cylindrical lens CY1 and the polarizing beam splitter PBS and incident on the reflection surface RPa of the polygon mirror PM is reflected toward the reflection mirror M10 at an angle corresponding to the angle change amount Δθ. .. At this time, with respect to the XY plane, the amount of change in the incident angle of the first reflection beam LB1b from the reflection surface RPa toward the reflection mirror M10 with respect to the optical axis AX2 is 2 × Δθ. The second reflection beam LB1c reflected by the reflection mirror M10 is incident on the reflection surface RPa of the polygon mirror PM again, and then is guided to the fθ lens FT via the polarization beam splitter PBS. At this time, the third reflected beam LB1d is reflected again at an angle corresponding to the angle change amount Δθ and is incident on the fθ lens FT. Therefore, with respect to the XY plane, the amount of change in the incident angle of the fθ lens FT of the third reflection beam LB1d with respect to the optical axis AXf is 4 × Δθ. In this way, the deflection angle of the first reflection beam LB1b when the beam LB1a is first reflected by the reflection surface RPa of the polygon mirror PM is twice the angle change amount Δθ of the reflection surface RPa of the polygon mirror PM. The deflection angle (angle of incidence on the fθ lens FT) of the third reflection beam LB1d reflected for the second time by the reflection surface RP is four times the angle change amount Δθ of the reflection surface RPa. Therefore, when the scanning length of the drawing line SL1 in which the spot light SP of the beam LB1 (LB1d) is scanned is constant, the reflection surface RPa reflects twice as compared with the case where the reflection surface RPa reflects once and scans. When scanning, the rotation angle of the polygon mirror PM required for effective scanning can be halved.

FIG. 9 is a diagram illustrating a rotation angle of the polygon mirror PM required for one scan. The angle θm shown in FIG. 9 is an angle at which the polygon mirror PM rotates by one reflection surface RP. In the first embodiment, since the polygon mirror PM is a rotating multifaceted mirror having eight reflecting surface RPs, the angle θm is 45 degrees (= 360 degrees / 8). While the polygon mirror PM rotates by an angle of θm, the angle θw that actually contributes to scanning the spot light SP is smaller than the angle θm. Then, when the scanning length of the drawing line SL1 is constant, the angle θw when scanning the spot light SP by reflecting it once on the reflecting surface RPa is set to θw1, and the spot light SP is reflected twice by the reflecting surface RPa. Let θw2 be the angle θw when scanning. Here, the angle θw1 is an angle range in which the beam (LB1a) reflected once by the reflecting surface RPa can be passed through the fθ lens FT1.

As described above, when the reflection surface RPa reflects once, the angle of incidence on the fθ lens FT becomes twice the angle change amount Δθ of the reflection surface RPa, and when the reflection surface RPa reflects twice, the fθ lens FT Since the change in the incident angle (deflection angle) of is four times the angle change amount Δθ of the reflecting surface RPa, the angles θw1 and θw2 are θw2 = 1/2 × θw1. Therefore, when the angle θw1 is set to, for example, 15 degrees, the scanning efficiency α1 of the reflecting surface RPa when the reflecting surface RPa reflects once and scans the spot light SP is α1 = θw1 / θm = 15 degrees / 45 degrees = 1 /. The scanning efficiency α2 of the reflecting surface RPa when the spot light SP is scanned by reflecting the light twice on the reflecting surface RPa is α2 = θw2 / θm = 7.5 degrees / 45 degrees = 1/6. ..

Therefore, while the reflecting surface RPa of the polygon mirror PM is rotated by one reflecting surface RP, the selection optical elements AOM1 to AOM6 are switched on one by one in order, so that the scanning unit Un on which the beam LBn is incident can be switched on. For example, it is possible to switch in the order of U1 → U2 → U3 → U4 → U5 → U6. That is, since the rotation angle θw2 that contributes to the actual scanning is 7.5 degrees, the rotation angle (45 °) in which the polygon mirror PM rotates by one reflecting surface RP is 37.5 degrees that does not contribute to the actual scanning. This period is wasted because the beam LBn is not incident on the polygon mirror PM of the scanning unit U1. Therefore, the beam LBn can be effectively utilized by selectively switching the beam LBn to the other scanning units U2 to U6 during this useless period and causing the beam LBn to be incident in a time-division manner. In each scanning unit Un (U1 to U6), the polygon mirror PM is rotated by 45 degrees from the start of scanning the spot light SP to the start of the next scanning.

Here, in order for the plurality of scanning units Un to scan the spot light SP in the order of, for example, U1 → U2 → U3 → U4 → U5 → U6, the polygon mirror PM of each scanning unit Un (U1 to U6) However, they need to rotate synchronously, and their rotation angle positions need to have a predetermined phase relationship. Further, the beam LBn is switched on during a period in which the scanning unit Un can scan the spot light SP by switching on any one of the plurality of selection optical elements AOMn (AOM1 to AOM6) of the beam switching unit BDU. Needs to be incident on the scanning unit Un. In order to realize this, a schematic configuration of a control circuit system provided in the control device 18 shown in FIG. 1 will be described below with reference to FIG.

First, the rotation control of the polygon mirror PMs of the plurality of scanning units Un (U1 to U6) will be described. Origin sensors OPn (OP1 to OP6) are provided in each scanning unit Un (U1 to U6). When the rotation position of the reflection surface RP of the polygon mirror PM of the scanning unit Un (U1 to U6) of each origin sensor OPn (OP1 to OP6) reaches a predetermined position where scanning of the spot light SP by the reflection surface RP can be started. A pulsed origin signal SZn (SZ1 to SZ6) is generated. In other words, each origin sensor OPn (OP1 to OP6) generates an origin signal SZn (SZ1 to SZ6) when the angle of the reflecting surface RP for scanning the spot light SP becomes a predetermined angle position. Since the polygon mirror PM has eight reflecting surface RPs, the origin sensor OPn (OP1 to OP6) has eight origin signals SZn (OP1 to OP6) during a period in which the polygon mirror PM of the scanning units Un (U1 to U6) makes one rotation. SZ1 to SZ6) will be output. The origin signals SZn (SZ1 to SZ6) generated by the origin sensors OPn (OP1 to OP6) are sent to the polygon drive control unit 20 of the control device 18. The origin sensor OPn 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 (continuous light emission) and generates the origin signal SZ1.

The polygon mirror PMs of the scanning units Un (U1 to U6) rotate about the rotation axis AXp by being driven by a rotation drive source RMn (RM1 to RM6) including a motor and the like. The polygon drive control unit 20 controls the rotation of the polygon mirror PM by controlling the rotation drive source RMn (RM1 to RM6) that rotates the polygon mirror PM of each scanning unit Un (U1 to U6). Based on the origin signals SZn (SZ1 to SZ6), the polygon drive control unit 20 scans a plurality of scanning units Un (U1 to U6) so that the rotation angle positions of the polygon mirrors PM have a predetermined phase relationship. The polygon mirror PMs of the units Un (U1 to U6) are synchronously rotated. That is, the plurality of scanning units Un (U1 to U6) have the same rotation speed (rotation speed) of the polygon mirrors PM, and the phases of the rotation angle positions are shifted by a certain angle. The rotation of the polygon mirror PMs (U1 to U6) is controlled.

Since the angle θw2 that contributes to the actual scanning of the spot light SP is 7.5 degrees in the present embodiment, the polygon drive control unit 20 has a rotation angle position of the polygon mirror PMs of the plurality of scanning units Un (U1 to U6). The rotation of the polygon mirror PMs of the plurality of scanning units Un (U1 to U6) is synchronously controlled so as to rotate at a constant speed in a state of being deviated by 7.5 degrees. In the first embodiment, the order of the scanning units Un on which the beam LBn is incident, that is, the order of the scanning units Un that scan the spot light SP is U1 → U2 → U3 → U4 → U5 → U6. Therefore, in this order, the rotation angle positions of the polygon mirrors PM of the plurality of scanning units Un (U1 to U6) are controlled to be displaced by 7.5 degrees.

Specifically, the polygon drive control unit 20 causes the origin signal SZ2 from the origin sensor OP2 of the scanning unit U2 to be generated with a delay of time Ts with reference to the origin signal SZ1 from the origin sensor OP1 of the scanning unit U1. In addition, the rotation of the polygon mirror PM of the scanning unit U2 is synchronously controlled. This time Ts is the time required for the polygon mirror PM to rotate by 7.5 degrees. Further, the polygon drive control unit 20 of the polygon mirror PM of the scanning unit U3 so that the origin signal SZ3 from the origin sensor OP3 of the scanning unit U3 is generated with a delay of 2 × time Ts with reference to the origin signal SZ1. Synchronous control of rotation. Similarly, the scanning units U4 to U6 are generated so that each of the origin signals SZ4, SZ5, and SZ6 is delayed by 3 × time Ts, 4 × time Ts, and 5 × time Ts with reference to the origin signal SZ1. Synchronously control the rotation of each polygon mirror PM. The polygon drive control unit 20 outputs the acquired origin signals SZ1 to Z6 to the AOM drive control unit 22 shown in FIG.

Next, the timing for switching on the plurality of selection optical elements AOMn (AOMn to AOM6) will be described. The AOM drive control unit (beam switching drive control unit) 22 shown in FIG. 10 controls a plurality of selection optical elements AOMn (AOM1 to AOM6) of the beam switching unit BDU, and one scanning unit Un is a spot light SP. From the start of the scan to the start of the next scan, the beam LB (LBn) from the light source device 14 is sequentially distributed to the six scanning units Un (U1 to U6) in a time-division manner.

Specifically, when the origin signal SZn (SZ1 to SZ6) is generated, the AOM drive control unit 22 outputs the origin signal SZn (SZ1 to SZ6) for a certain period of time (on-time Ton) after the origin signal SZn is generated. A drive signal (high frequency signal) HFn (HF1 to HF6) is applied to the selection optical elements AOMn (AOM1 to AOM6) corresponding to the generated scanning units Un (U1 to U6). As a result, the selection optical element AOMn to which the drive signal (high frequency signal) HFn is applied is turned on for the on-time Ton, and the beam LBn can be incident on the corresponding scanning unit Un. Further, since the beam LBn is incident on the scanning unit Un that generates the origin signal SZn, the beam LBn can be incident on the scanning unit Un that can scan the spot light SP. The on-time Ton is a time Ts or less for the polygon mirror PM to rotate 7.5 degrees.

The origin signals SZ1 to SZ6 generated by the six scanning units U1 to U6 are generated in the order of SZ1 → SZ2 → SZ3 → SZ4 → SZ5 → SZ6 at time Ts intervals. Therefore, drive signals (high frequency signals) HFn are applied to the plurality of selection optical elements AOM1 to AOM6 in the order of HF1 → HF2 → HF3 → HF4 → HF5 → HF6 at time Ts intervals. Therefore, one scanning unit Un on which the beam LBn from the light source device 14 is incident can be switched in the order of U1 → U2 → U3 → U4 → U5 → U6 at time Ts intervals, and a plurality of scanning units Un (U1) can be switched. ~ U6) can scan the spot light SP in this order.

The light source device 14 has a control circuit 14a. The control circuit 14a controls a semiconductor laser device (not shown) of the light source device 14 so as to generate a clock signal LTC at an oscillation frequency Fa and emit seed light in response to the clock signal LTC. The seed light in the infrared region emitted by the semiconductor laser element is amplified by the fiber amplifier, and the pulsed light in the infrared wavelength region amplified by the wavelength conversion element is converted into pulsed light in the ultraviolet wavelength region. The converted pulsed light in the ultraviolet wavelength region is output from the light source device 14 as a beam LB. Further, the intensity of the beam LB emitted by the light source device 14 is high or low according to the pattern of one line (one drawing line SLn) drawn by the scanning unit Un incident on the beam LB (LBn). The beam LBn is modulated to the level. For example, during the period in which the beam LBn is incident on the scanning unit U1, the intensity of the beam LB emitted from the light source device 14 is intensity-modulated according to the pattern of one drawing line SL1 drawn by the scanning unit U1. .. As described above, the configuration of such a light source device 14 is disclosed in Japanese Patent Application Laid-Open No. 2015-210437. The clock signal LTC generated by the control circuit 14a is output to the polygon drive control unit 20, the AOM drive control unit 22, and the controller 24 provided in the control device 18. The polygon drive control unit 20, the AOM drive control unit 22, and the controller 24 operate according to the clock signal LTC. The controller 24 functions as a general control unit that controls the polygon drive control unit 20, the AOM drive control unit 22, and the light source device 14. The polygon drive control unit 20 outputs the acquired origin signal SZn (SZ1 to SZ6) to the controller 24, and the controller 24 uses the origin signal SZn (SZ1 to SZ6) to scan the spot light SP from now on. Manages Un (U1 to U6). Then, the controller 24 outputs the pattern information for one line (one scan of the spot light SP) drawn by the scanning unit Un that scans the spot light SP to the light source device 14. The light source device 14 modulates the intensity of the beam LB emitted based on this pattern information at high speed with a time resolution corresponding to the period of the clock signal LTC.

In this way, since the beam LBn is reflected twice on the reflecting surface RPa of the polygon mirror PM and the polarized spot light SP of the beam LBn is projected onto the substrate P, the scanning speed of the spot light SP can be increased. .. Further, the scanning efficiency of the reflecting surface RP of the polygon mirror PM can be lowered, that is, the rotation angle of the polygon mirror PM that contributes to the actual scanning can be reduced. Therefore, while the polygon mirror PM rotates by one reflecting surface RP, The beam LBn can be distributed to more scanning units Un in a time-divided manner. Further, using the cylindrical lenses CY1 and CY2, the beam LB1 first incident on the reflecting surface RPa in the non-scanning direction (Z direction or the direction of the rotation axis AXp) orthogonal to the main scanning direction (deflection direction) by the polygon mirror PM. The position of the beam LB1 that is incident again (the second time) is set to the same position. Thereby, the thickness of the polygon mirror PM (the length in the rotation axis AXp direction) can be reduced. Therefore, the weight of the polygon mirror PM can be reduced, and the rotation speed of the polygon mirror PM is improved.

Further, as described with reference to FIG. 9, since the deflection angle (rotation angle) θw2 when scanning the beam LBn (LB1d) by the polygon mirror PM is halved, the scanning efficiency of the polygon mirror PM on one reflecting surface RPa. Although it is assumed that α1 is also halved, if the scanning efficiency α1 can be kept at 1/3, the angle θm corresponding to one reflecting surface RP of the polygon mirror PM can be halved, so that the polygon mirror PM can be used as a polygon mirror PM. 16 Reflective surface RP can be used. Further, in the present embodiment, the reflection surface of the reflection mirror M10 shown in FIGS. 6 and 7 has been described as a plane parallel to the YZ plane, but a concave spherical surface or a concave cylindrical surface having a large radius of curvature May be. By making the reflection surface of the reflection mirror M10 a curved surface, the influence of a slight position change in the Z direction of the reflection beam LB1b that may occur due to the deviation between the reflection surface RP of the polygon mirror PM and the rotation axis AXp (drawing line SLn). Distortion, etc.) can be corrected or alleviated.

[Modified example of the first embodiment]
The first embodiment is deformable as follows.

(Modification 1) FIG. 11 is a diagram showing a configuration of a scanning unit U1a in the modification 1. The same reference numerals are given to the same configurations as those in the first embodiment. Further, also in the present modification 1, six scanning units Una (U1a to U6a) having the same configuration as the scanning unit U1a of FIG. 11 are provided in the arrangement as shown in FIG. Since the plurality of scanning units Una (U1a to U6a) have the same configuration, the scanning unit U1a will be described as an example. The scanning unit U1a includes a reflection mirror M12, a cylindrical lens CY1, a polarization beam splitter PBS, a λ / 4 wave plate QP, a polygon mirror PM, a cylindrical lens CY2, a reflection mirror M10, an fθ lens FT, and a cylindrical lens CY3. The polarizing beam splitter PBS and the λ / 4 wave plate QP form an optical splitting member, and the cylindrical lens CY1 and the reflection mirror M10 form a rereflection optical system. Further, the fθ lens FT and the cylindrical lens CY3 form a scanning optical system.

The beam LB1 of the parallel luminous flux reflected in the −Z direction by the incident mirror (epi-illuminating mirror as a light guide member) IM1 shown in FIG. 5 and expanded to a predetermined diameter is along the optical axis AX1 parallel to the Z axis. Then it enters the scanning unit U1a. The beam LB1 incident on the scanning unit U1a (hereinafter, may be referred to as an incident beam LB1a) is formed along the optical axis AX3 parallel to the X axis by the reflection mirror M12 provided at 45 ° on the optical axis AX1. It is reflected in the X direction. The incident beam LB1a reflected in the −X direction by the reflection mirror M12 is a polygon via a cylindrical lens CY1 having a bus in the Y direction provided on the optical axis AX3, a polarization beam splitter PBS, and a λ / 4 wave plate QP. It is incident on the reflecting surface RPa of the mirror PM. As described in the first embodiment, the beam LB1 is P-polarized light, and the polarizing beam splitter PBS transmits P-polarized light and reflects S-polarized light. I dare to add it.

In the polygon mirror PM, the incident beam LB1a incident on the reflection surface RPa of the polygon mirror PM from the reflection mirror M12 is provided at a position on the + X direction side of the polygon mirror PM and at a position on the + Z direction side of the polarization beam splitter PBS. The plane orthogonal to the rotation axis AXp of the polygon mirror PM is arranged so as to be tilted by a slight angle of less than 45 ° with respect to the XY plane so as to be reflected toward the reflection mirror M10. The polygon mirror PM deflects the reflected light of the incident beam LB1a reflected by the reflecting surface RPa (hereinafter, the first reflected beam LB1b) in a plane that includes the optical axis AX4 and is inclined with respect to the XY plane. A generatrix extending in the Y direction of the cylindrical lens CY2 is located on a plane on which the first reflected beam LB1b is polarized. The plane including the optical axes AX1, AX3, AX4, and the rotation axis AXp is parallel to the XZ plane.

The cylindrical lens CY1 having a bus in the Y direction polygons the incident beam LB1a in the non-scanning direction (Z direction or the direction of the rotation axis AXp) orthogonal to the main scanning direction (rotation direction, deflection direction) by the polygon mirror PM. Converges on the reflective surface RPa of the mirror PM. That is, the cylindrical lens CY1 converges the incident beam LB1a in a slit shape (oblong shape) extending in the Y direction on the reflection surface RPa.

The first reflection beam LB1b reflected by the reflection surface RPa of the polygon mirror PM passes through the cylindrical lens CY2 and is incident on the reflection mirror M10. The first reflected beam LB1b reflected by the reflecting surface RPa is incident on the cylindrical lens CY2 while diverging in the non-scanning direction (Z direction) orthogonal to the main scanning direction by the polygon mirror PM, but the cylindrical having a bus in the Y direction. It is made into parallel light by the lens CY2. Therefore, the first reflected beam LB1b incident on the reflection mirror M10 is a parallel light flux having substantially the same diameter as the incident beam LB1a incident on the cylindrical lens CY1. The rear focal point of the cylindrical lens CY1 and the anterior focal point of the cylindrical lens CY2 coincide with each other within a predetermined allowable range on the reflecting surface RPa.

The reflection mirror M10 reflects the first reflection beam LB1b first reflected by the reflection surface RPa of the polygon mirror PM toward the reflection surface RPa of the polygon mirror PM again. The reflected light of the first reflected beam LB1b reflected by the reflection mirror M10 (hereinafter, may be referred to as the second reflected beam LB1c) passes through the cylindrical lens CY2 and is incident on the reflecting surface RPa. Therefore, the second reflection beam LB1c incident on the reflection surface RPa by the cylindrical lens CY2 is reflected in the non-scanning direction (Z direction or the direction of the rotation axis AXp) orthogonal to the main scanning direction (deflection direction) by the polygon mirror PM. Converges on the surface RPa. That is, the cylindrical lens CY2 converges the second reflection beam LB1c in a slit shape (oblong shape) extending in the Y direction on the reflection surface RPa. Converging position on the reflecting surface RPa by the cylindrical lens CY1 and on the reflecting surface RPa by the cylindrical lens CY2 with respect to the non-scanning direction (Z direction or the direction of the rotation axis AXp) orthogonal to the main scanning direction (deflection direction) by the polygon mirror PM. It is set to almost the same position as the convergence position of. Thereby, the thickness of the polygon mirror PM (the length in the rotation axis AXp direction) can be reduced.

The reflection surface RPa of the polygon mirror PM reflects the second reflection beam LB1c reflected by the reflection mirror M10 toward the + X direction side. The reflected light of the beam LB1 (second reflected beam LB1c) reflected again by the reflecting surface RPa may be referred to as a third reflected beam LB1d. The polygon mirror PM includes an optical axis AX3 parallel to the X axis, deflects the third reflection beam LB1d in a plane parallel to the XY plane, and deflects the third reflection beam LB1d in the Y direction about the optical axis AX3. The third reflection beam LB1d reflected again by the reflection surface RPa of the polygon mirror PM is incident on the polarization beam splitter PBS. Since a λ / 4 wavelength plate QP is provided between the polygon mirror PM and the polarizing beam splitter PBS, the third reflection beam is reflected again by the reflecting surface RP of the polygon mirror PM and incident on the polarizing beam splitter PBS. LB1d is reflected toward the substrate P in the −Z direction by the polarization splitting surface Qs of the polarizing beam splitter PBS. The polarization separation surface Qs reflects the beam LB1d toward the fθ lens FT so that the optical axis of the beam LB1d overlaps the azimuth line Lx2 and the optical axis AXf of the fθ lens FT with respect to the XZ plane.

The fθ lens FT is a telecentric system that projects the main ray of the beam LB1d reflected by the polygon mirror PM onto the substrate P so as to be parallel to the optical axis AXf in a plane orthogonal to the XZ plane including the optical axis AXf. It is a scan lens. The fθ lens FT scans the beam LB1d projected on the substrate P around the optical axis AXf in the Y direction. The angle of incidence θ of the beam LB1d on the fθ lens FT changes according to the rotation angle (θ / 4) of the polygon mirror PM. The fθ lens FT projects the beam LB1d at the image height position on the irradiated surface of the substrate P in proportion to the incident angle θ via the cylindrical lens CY3. Further, the beam LB1d projected on the substrate P is converged by the spot light SP on the substrate P by the fθ lens FT and the cylindrical lens CY3. The plane including the optical axes AX1, AX3, AX4, and AXf is parallel to the XZ plane, and when the angle of incidence θ on the fθ lens FT is 0 degrees, the beam LB1d incident on the fθ lens FT is on the optical axis AXf. Proceed along. The front focal point of the fθ lens FT is located on the reflecting surface RPa of the polygon mirror PM on which the beam LB is incident, and the rear focal point is located on the substrate P. Further, the rear focal point of the cylindrical lens CY3 is located on the substrate P. Also in the present modification 1, the same actions and effects as those of the first embodiment can be obtained. Further, in this modification, the incident angles of the beam LB1a and the beam LB1c incident on the reflecting surface RPa of the polygon mirror PM are smaller than those in the cases of FIGS. 6 and 7 (incident angle is 45 °). Therefore, the influence of a slight position change in the Z direction of the reflected beams LB1b and LB1d (degree of distortion of the drawing line SLn) that may occur due to the deviation between the reflecting surface RP of the polygon mirror PM and the rotation axis AXp is shown in FIG. , Can be reduced as compared with the case of FIG.

(Modification 2) FIG. 12 is a configuration diagram for reflecting the beam LBn twice on the reflection surface RPa of the polygon mirror PM in the modification 2. The same reference numerals are given to the same configurations as those in the first embodiment. The beam LB1a incident on the polygon mirror PM by a cylindrical lens having a bus in the Y direction (not shown) is on the reflecting surface RPa with respect to the non-scanning direction (Z direction) orthogonal to the main scanning direction (deflection direction) by the polygon mirror PM. It shall be converged. The beam LB1b reflected by the reflection surface RPa of the polygon mirror PM is incident on the reflection mirror M20 via the relay lens system G20. The reflection mirror M20 reflects the incident beam LB1b toward the reflection surface RPa of the polygon mirror PM. The reflected beam LB1c of the beam LB1b reflected by the reflection mirror M20 passes through the relay lens system G20 again and is incident on the reflecting surface RPa of the polygon mirror PM. Due to this relay lens system G20, the reflection surface RPa and the reflection mirror M20 have a conjugate relationship. Therefore, the beam LB1b incident on the reflection mirror M20 converges in the Z direction on the reflection surface of the reflection mirror M20 with respect to the non-scanning direction (Z direction) orthogonal to the main scanning direction (deflection direction) by the polygon mirror PM. Further, the beam LB1c incident on the reflection surface RPa of the polygon mirror PM from the reflection mirror M20 is also in the Z direction on the reflection surface RPa with respect to the non-scanning direction (Z direction) orthogonal to the main scanning direction (deflection direction) by the polygon mirror PM. Is converged on. Then, the beam LB1c re-entered on the reflection surface RPa of the polygon mirror PM is reflected as the beam LB1d toward the fθ lens FT. With respect to the Z direction orthogonal to the scanning direction of the polygon mirror PM, the convergence position of the beam LB1a first incident on the reflection surface RPa and the convergence position of the beam LB1c re-incident on the reflection surface RPa are substantially the same. Also in the second modification, the same effect as that of the first embodiment can be obtained. Further, by using a relay lens system G20 having a short focal length, the optical path length from the polygon mirror PM to the reflection mirror M20 can be shortened, or the aperture of the lens can be reduced.

[Second Embodiment]
Next, the scanning unit U1b of the second embodiment will be described. FIG. 13A is a view when the configuration of the scanning unit U1b of the second embodiment is viewed from the −Y direction, and FIG. 13B is a diagram when the configuration of the scanning unit U1b of the second embodiment is viewed from the + Z direction. Is. The same components as those in the first embodiment are designated by the same reference numerals. Further, since the scanning units Unb (U1b to U6b) have the same configuration, only the scanning unit U1b will be described as an example. Further, in the second embodiment, it is assumed that the substrate P is conveyed in the + X direction in parallel with the XY plane. The scanning unit U1b includes a cylindrical lens CYa to CYd having a bus in the Y direction, a polarizing beam splitter PBS1, PBS2, a λ / 4 wave plate QP1, QP2, an fθ lens FT1, an imaging lens FT2, a polygon mirror PM, and a reflection mirror. It is equipped with M30. The polarizing beam splitters PBS1 and PBS2 and the λ / 4 wave plates QP1 and QP2 form an optical splitting member, and the fθ lens FT1 and the cylindrical lens (third optical member) CYd form a scanning optical system. Further, the cylindrical lens (first optical member) CYb, CYc and the reflection mirror M30 constitute a rereflection optical system.

The beam LB1 of the parallel light beam reflected in the −Z direction by the incident mirror (light guide member) IM1 shown in FIG. 5 is incident on the scanning unit U1b along the optical axis AX1 parallel to the Z axis. In the present embodiment, the beam LB1 incident on the scanning unit U1b (hereinafter, may be referred to as an incident beam LB1a) is scanned after being focused on a circular spot on the surface p1 by a condenser lens (not shown). Since it is incident on the unit U1b, it is incident on the scanning unit U1b while diverging. The incident beam LB1a incident on the scanning unit U1b passes through a cylindrical lens (second optical member) CYa provided along the optical axis AX1 and having a generatrix in the Y direction, and is incident on the polarizing beam splitter PBS1. The polarization separation surface Qs of the polarization beam splitter PBS1 is tilted 45 degrees with respect to the XY plane, reflects P-polarized light, and transmits S-polarized light. Therefore, the incident beam LB1a (P-polarized light) incident on the polarizing beam splitter PBS1 through the cylindrical lens CYa is reflected in the −X direction by the polarization splitting surface Qs of the polarizing beam splitter PBS1. The incident beam LB1a reflected in the −X direction on the polarization separation surface Qs of the polarization beam splitter PBS1 is a polygon via the λ / 4 wave plate QP1 and the fθ lens FT1 provided in the −X direction of the polarization beam splitter PBS1. It is incident on the reflecting surface RPa of the mirror PM. The optical axis AXf1 of the fθ lens FT1 is parallel to the X axis, and the rotation axis AXp of the polygon mirror PM is set to be parallel to the Z axis. The plane including the optical axis AXf1 and the rotation axis AXp is parallel to the XZ plane. At this time, the incident beam LB1a is incident on the fθ lens FT1 from the ejection side of the fθ lens FT1. The reflection surface RP of the polygon mirror PM is arranged at the position of the entrance pupil (position of the front focal point) of the fθ lens FT1.

Here, the cylindrical lens CYa makes the incident beam LB1a incident while diverging parallel light in the non-scanning direction (Z direction) orthogonal to the main scanning direction (rotation direction, deflection direction) by the polygon mirror PM (FIG. See 13A). Further, the cylindrical lens CYa transmits the incident beam LB1a while diverging in the main scanning direction (rotational direction, deflection direction) by the polygon mirror PM as it is (see FIG. 13B). It is assumed that the front focal point of the cylindrical lens CYa is set on the surface p1. The fθ lens FT1 converges the incident beam LB1a made into parallel light by the cylindrical lens CYa with the reflection surface RPa of the polygon mirror PM in the non-scanning direction orthogonal to the main scanning direction (rotation direction, deflection direction) by the polygon mirror PM. (See FIG. 13A). Further, the fθ lens FT1 makes the incident beam LB1a into parallel light while diverging in the XY plane which is the main scanning direction (rotation direction, deflection direction) by the polygon mirror PM (see FIG. 13B). As a result, the incident beam LB1a projected on the reflecting surface RPa is converged in a slit shape (oblong shape) extending in the Y direction on the reflecting surface RP (see FIGS. 13A and 13B).

In the XZ plane, the incident beam LB1a traveling from the polarizing beam splitter PBS1 toward the reflection surface RPa of the polygon mirror PM via the fθ lens FT1 passes through the position on the + Z direction side of the optical axis AXf1 of the fθ lens FT1. The position of incident on the reflecting surface RPa and converging on the reflecting surface RPa substantially coincides with the optical axis AXf1 of the fθ lens FT1 (see FIG. 13A). Further, in the XY plane, the incident beam LB1a traveling from the polarizing beam splitter PBS1 toward the reflecting surface RPa of the polygon mirror PM via the fθ lens FT1 overlaps with the optical axis AXf1 of the fθ lens FT1 and is incident on the reflecting surface RPa. (See FIG. 13B). Here, the reflective surface RPa of the polygon mirror PM is set to the pupil position (position of the front focal point) of the fθ lens FT1, and the rear focal point of the fθ lens FT1 is in the + X direction from the polarizing beam splitter PBS1 in FIGS. 13A and 13B. It is set at the position of the surface p2 separated from. The surface p2 is set to have an optically conjugate relationship with the surface p1, and is finally set to a conjugate relationship with the surface of the substrate P.

The reflection surface RPa of the polygon mirror PM reflects the incident beam LB1a toward the fθ lens FT1 in the + X direction. The incident beam LB1a is deflected in the Y direction by the rotation of the polygon mirror PM. The reflected light of the incident beam LB1a reflected by the reflecting surface RPa (hereinafter referred to as the first reflected beam LB1b) is deflected in the Y direction about the optical axis AXf1 with respect to the XY plane by the rotated polygon mirror PM. The first reflected beam LB1b reflected by the reflecting surface RPa is incident on the fθ lens FT1 through the −Z direction side of the optical axis AXf1 of the fθ lens FT1 with respect to the XZ plane.

The first reflected beam LB1b from the reflecting surface RPa toward the fθ lens FT is incident on the fθ lens FT1 while diverging in the non-scanning direction orthogonal to the main scanning direction (deflection direction) by the polygon mirror PM, but the fθ lens FT1 (See FIG. 13A). Further, the first reflected beam LB1b from the reflecting surface RPa toward the fθ lens FT is incident on the fθ lens FT1 as parallel light in the XY plane including the main scanning direction (deflection direction) by the polygon mirror PM, but the fθ lens FT1 Converges as a circular spot on surface p2 (see FIG. 13B).

The first reflection beam LB1b transmitted through the fθ lens FT1 is transmitted through the λ / 4 wave plate QP2 and incident on the polarization beam splitter PBS2. The λ / 4 wave plate QP2 and the polarization beam splitter PBS2 are arranged on the −Z direction side of the λ / 4 wave plate QP1 and the polarization beam splitter PBS1 via a light-shielding plate DO. The shading plate DO includes the optical axis AXf1 of the fθ lens FT1 and is provided on a plane parallel to the XY plane. The polarization separation surface Qs of the polarization beam splitter PBS1 is tilted 45 degrees with respect to the XY plane, reflects P-polarized light, and transmits S-polarized light. Here, the incident beam LB1a first incident on the polygon mirror PM is converted from P-polarized light to circularly polarized light by the λ / 4 wave plate QP1, and the first reflected beam LB1b first reflected by the polygon mirror PM is λ. It is converted from circularly polarized light to S-polarized light by the / 4 wave plate QP2. Therefore, the first reflection beam LB1b incident on the polarizing beam splitter PBS2 passes through the polarizing beam splitter PBS2 as it is.

The first reflection beam LB1b that passes through the polarizing beam splitter PBS2 and travels toward the −X direction passes through the cylindrical lens (first optical member) CYb arranged on the + X direction side of the polarizing beam splitter PBS2 and the imaging lens FT2. It is incident on the reflection mirror M30. The cylindrical lens CYb whose posterior focal point is set on the surface p2 passes through the fθ lens FT1 and the polarizing beam splitter PBS2 in the non-scanning direction (Z direction) orthogonal to the main scanning direction (deflection direction) by the polygon mirror PM. The first reflection beam LB1b of the parallel light is converged on the surface p2 (see FIG. 13A). Since this surface p2 is also the position of the rear focal point of the fθ lens FT1, the first reflection beam LB1b transmitted through the fθ lens FT1 and the polarizing beam splitter PBS2 is also a surface in the main scanning direction (deflection direction) by the polygon mirror PM. It converges on p2 (see FIG. 13B). The surface p1 and the surface p2 have a conjugate relationship. The reflection mirror M30 is arranged as a concave spherical reflector at the position of the rear focal point of the imaging lens FT2, that is, at the pupil position for aberration correction, but in principle, it may be a planar reflector. .. Further, the system in which the imaging lens FT2 and the reflection mirror M30 are combined functions as an equal-magnification relay optical system having telecentric imaging characteristics on the surface p2 side, and is focused on the surface p2 by the convergence of the beam LB1b. The spot light is imaged again as a converged spot light of the beam LB1c at different positions on the surface p2.

Therefore, the first reflected beam LB1b directed to the reflection mirror M30 via the imaging lens FT2 is incident on the imaging lens FT2 in a divergent state, but after being converted into a parallel light flux by the imaging lens FT2, the reflection mirror M30. Incident. The optical axis AXf2 of the imaging lens FT2 and the optical axis AXf1 of the fθ lens FT1 are set coaxially. The first reflection beam LB1b incident on the imaging lens FT2 is incident on the imaging lens FT2 through the −Z direction side of the optical axis AXf2 with respect to the XZ plane, and is the central axis of the first reflection beam LB1b on the reflection mirror M30. Aligns with the optical axis AXf2 (see FIG. 13A). The position of the posterior focal point (pupil surface) of the imaging lens FT2 is set on the surface p2.

The reflected light of the first reflected beam LB1b (hereinafter referred to as the second reflected beam LB1c) reflected by the reflection mirror M30 in the −X direction passes through the imaging lens FT2 and the cylindrical lens (first optical member) CYc. It re-enters the polarized beam splitter PBS1. The second reflected beam LB1c passes through the + Z direction side of the optical axis AXf2 and is incident on the imaging lens FT2. The imaging lens FT2 converges the second reflected beam LB1c of the parallel light flux reflected by the reflection mirror M30 into a circular spot on the surface p2. The second reflection beam LB1c converged on the surface p2 is incident on the cylindrical lens CYc having a generatrix parallel to the Y axis while diverging, and then incident on the polarization beam splitter PBS1. The second reflection beam LB1c incident on the polarizing beam splitter PBS1 is made parallel by the cylindrical lens CYc in the non-scanning direction (Z direction) orthogonal to the main scanning direction (deflection direction) by the polygon mirror PM, and is made parallel to the polygon mirror PM. With respect to the main scanning direction (deflection direction), the light is incident on the polarizing beam splitter PBS1 while diverging as it is. Since the second reflected beam LB1c incident on the polarizing beam splitter PBS1 is S-polarized light, it passes through the polarizing beam splitter PBS1 as it is. The second reflection beam LB1c transmitted through the polarization beam splitter PBS1 passes through the λ / 4 wave plate QP1 and the fθ lens FT1 and re-enters the reflection surface RPa of the polygon mirror PM. The second reflected beam LB1c is incident on the fθ lens FT1 from the ejection side of the fθ lens FT1.

The fθ lens FT1 converges the incident second reflection beam LB1c on the reflection surface RP (RPa) of the polygon mirror PM in a slit shape (oblong shape) extending in the Y direction. At this time, the incident position on the reflection surface RPa of the second reflection beam LB1c and the incident position on the reflection surface RPa of the incident beam LB1a are the same with respect to the Z direction orthogonal to the scanning direction (deflection direction) of the polygon mirror PM. .. The reflected light of the second reflected beam LB1c (hereinafter referred to as the third reflected beam LB1d) reflected again by the reflecting surface RPa enters the polarizing beam splitter PBS2 through the fθ lens FT1 and the λ / 4 wave plate QP2. Here, the second reflected beam LB1c re-incidents on the polygon mirror PM is converted from S-polarized light to circularly polarized light by the λ / 4 wave plate QP1, and the third reflected beam LB1d reflected again by the polygon mirror PM is λ. It is converted from circularly polarized light to P-polarized light by the / 4 wave plate QP2. Therefore, the third reflection beam LB1d incident on the polarization beam splitter PBS2 is reflected in the −Z direction on the polarization separation surface Qs of the polarization beam splitter PBS2 and projected onto the substrate P. The third reflection beam LB1d reflected in the −Z direction on the polarization separation surface Qs is projected onto the substrate P through the cylindrical lens (third optical member) CYd. The beam LB1 (third reflection beam LB1d) projected from the scanning unit U1b toward the substrate P is projected along the normal line of the substrate P.

Here, the fθ lens FT1 converges the third reflected beam LB1d of the parallel light reflected by the reflecting surface RPa and incident on the substrate P with respect to the scanning direction (deflection direction) of the polygon mirror PM. Further, the fθ lens FT1 makes the third reflected beam LB1d, which is reflected by the reflecting surface RPa and diverges, into parallel light in the direction orthogonal to the scanning direction (deflection direction) of the polygon mirror PM, but is a cylindrical lens. It is converged on the substrate P by CYd. As a result, the beam LB1 (third reflected beam LB1d) projected on the substrate P becomes a spot light SP and is projected onto the substrate P. In this way, the surface p1, the surface p2, and the substrate P are in a conjugate relationship with each other.

Here, as shown in FIG. 13A, in the direction orthogonal to the scanning direction (deflection direction) of the polygon mirror PM (for the XZ plane), the first reflection from the reflection surface RPa of the polygon mirror PM toward the reflection mirror M10. The optical path and shape of the beam LB1b and the optical path and shape of the second reflection beam LB1c from the reflection mirror M30 toward the reflection surface RPa of the polygon mirror PM include the optical axis AXf1 (AXf2) with respect to a plane parallel to the XY plane. Is symmetrical. Further, the optical path and shape of the incident beam LB1a first directed from the polarizing beam splitter PBS1 to the reflecting surface RPa of the polygon mirror PM, and the optical path of the second reflecting beam LB1c directed again from the polarizing beam splitter PBS1 to the reflecting surface RPa of the polygon mirror PM. The shape is the same (with respect to the XZ plane) in a direction orthogonal to the scanning direction (polarization direction) of the polygon mirror PM. Further, the optical path and shape of the first reflection beam LB1b from the reflection surface RPa of the polygon mirror PM to the polarizing beam splitter PBS2, and the optical path and shape of the third reflection beam LB1d from the reflection surface RPa of the polygon mirror PM to the polarization beam splitter PBS2. Is the same (with respect to the XZ plane) in a direction orthogonal to the scanning direction (deflection direction) of the polygon mirror PM.

On the other hand, as shown in FIG. 13B, with respect to the scanning direction (deflection direction) of the polygon mirror PM (with respect to the XY plane), the first reflection beams LB1b to the third are depending on the angle of the reflection surface RPa of the polygon mirror PM. The optical path of the reflected beam LB1d is different. Here, the angle of the reflecting surface RPa with respect to the YZ plane is Δθ. Regarding the scanning direction (deflection direction) of the polygon mirror PM (with respect to the XY plane), it is reflected by the reflection surface RPa of the polygon mirror PM with respect to the optical axis AXf1 (central axis of the incident beam LB1a) of the fθ lens FT1 and is incident on the fθ lens FT1. The angle (absolute value) of the central axis (main ray) of the first reflected beam LB1b is 2 × Δθ. Further, regarding the scanning direction (deflection direction) of the polygon mirror PM (with respect to the XY plane), the second reflection that re-enters the reflection surface RP of the polygon mirror PM with respect to the optical axis AXf1 (central axis of the incident beam LB1a) of the fθ lens FT1. The angle (absolute value) of the central axis (main ray) of the beam LB1c is 2 × Δθ. Therefore, regarding the scanning direction (deflection direction) of the polygon mirror PM (with respect to the XY plane), the central axis (main ray) of the first reflected beam LB1b reflected by the reflecting surface RPa of the polygon mirror PM and incident on the fθ lens FT1 and the like. The convergent divergence state and the central axis (main ray) and the convergent divergence state of the second reflection beam LB1c re-incident on the reflection surface RP of the polygon mirror PM are symmetrical with respect to the optical axis AXf1 (central axis of the incident beam LB1a). It becomes. Further, regarding the scanning direction (deflection direction) of the polygon mirror PM (with respect to the XY plane), the fθ lens FT1 is reflected by the reflection surface RPa of the polygon mirror PM with respect to the optical axis AXf1 (central axis of the incident beam LB1a) of the fθ lens FT1. The angle (absolute value) of the optical axis (central axis) of the third reflected beam LB1d incident on the lens is 4 × Δθ.

Therefore, the same effect as that of the first embodiment can be obtained even in the second embodiment. The system in which the imaging lens FT2 and the reflection mirror M30 shown in FIGS. 13A and 13B are combined is a telecentric equal-magnification relay optical system similar to the relay lens system G20 shown in FIG. By using a lens with a short focal length as the lens FT2, the configuration from the surface p2 to the reflection mirror M30 can be made compact.

[Modified example of the second embodiment]
The second embodiment can be modified as follows.

(Modification 1) In the case of the scanning unit Unb of the second embodiment, the scanning unit Unb becomes longer in the optical axes AXf1 and AXf2 directions of the fθ lens FT1 and the imaging lens FT2. Therefore, as shown in FIG. 14, while the substrate P is curved and supported by the rotating drum DR described in the first embodiment, the scanning unit Unb shown in the second embodiment is mounted on the substrate P. When a plurality of scanning units are arranged along the transport direction, the odd and even numbers of the plurality of scanning units Unb arranged along the transport direction (X direction) of the substrate P are in the X direction (circumferential direction of the rotating drum DR). Must be placed apart from each other. As a result, the distance between the drawing lines SLn (projection position of the spot light SP) of the plurality of scanning units Unb arranged along the transport direction becomes long. Therefore, with respect to the transport direction of the substrate P, the alignment accuracy may be lowered only by providing one alignment microscope AMm (AM1 to AM4) on the upstream side of the plurality of scanning units Unb. Therefore, in the present modification 1, as shown in FIG. 14, the substrate P is provided with respect to the respective positions of the odd-numbered scanning unit Unb and the even-numbered scanning unit Unb provided along the transport direction of the substrate P. A plurality of alignment microscopes AMm (AM1 to AM4) may be provided on the upstream side in the transport direction.

(Modification 2) In the second embodiment, one beam LB1a is incident on one scanning unit Unb, but two beams LBn (LB1a) are attached to the cylindrical lens CYa of one scanning unit Unb. The incident may be made slightly separated in the Y direction. In this case, each central axis of the two beams LB1a incident on the cylindrical lens CYa is located on a plane parallel to the optical axis AX1 and parallel to the YZ plane including the optical axis AX1. As a result, the pattern can be drawn at a higher speed because it is scanned by the two spot light SPs. Further, by making the two beams LB1a incident on the scanning unit Unb so that the scanning regions of the two spot light SPs are shared, the rotation angle that contributes to the actual scanning of the polygon mirror PM can be further halved.

[Third Embodiment]
In the first and second embodiments (including modified examples), the reflection surface RP of the polygon mirror PM that reflects the beam LBn (LB1a) for the first time and the beam LBn (LB1c) for the second time are reflected. The beam LBn was incident on the polygon mirror PM so that the reflection surface RP of the polygon mirror PM was the same. However, in the third embodiment, the reflection surface RP of the polygon mirror PM that reflects the beam LBn the first time and the reflection surface RP of the polygon mirror PM that reflects the beam LBn the second time are different. Change the configuration of the reflective optical member.

FIG. 15 is a configuration diagram for reflecting the drawing beam LBn twice on the polygon mirror PM in the third embodiment. The same reference numerals are given to the same configurations as those of the first and second embodiments. In the present embodiment, the rereflection optical member is configured so that the reflection surface RP of the polygon mirror PM that reflects the beam LBn for the first time and the reflection surface RP of the polygon mirror PM that reflects the beam LBn for the second time are different. To do.

In FIG. 15, the beam LB1a incident on the polygon mirror PM by a cylindrical lens having a bus in the Y direction (not shown) is in a non-scanning direction (direction of rotation axis AXp) orthogonal to the main scanning direction (deflection direction) by the polygon mirror PM. It is assumed that the light is converged on the reflective surface RPa. The beam LB1b reflected by the reflection surface RPa of the polygon mirror PM is incident on the reflection mirror M50 through the relay lens system G30, reflected by the reflection mirror M50, and then incident on the reflection mirror M51. Due to this relay lens system G30, the reflection surface RPa and the reflection mirror M51 are in a conjugate relationship. Therefore, the beam LB1b incident on the reflection mirror M51 converges on the reflection surface of the reflection mirror M51 with respect to the non-scanning direction (direction of the rotation axis AXp) orthogonal to the main scanning direction (deflection direction) by the polygon mirror PM. Further, the beam LB1c reflected by the reflection mirror M51 is reflected by the reflection mirror M52 and then enters the reflection surface RP of the polygon mirror PM through the relay lens system G31. The reflection surface RP on which the beam LB1c is incident through the relay lens system G31 is a reflection surface RP (hereinafter, RPb) different from the reflection surface RPa. Due to the relay lens system G31, the reflection mirror M51 and the reflection surface RPb are in a conjugate relationship. Therefore, the beam LB1c incident on the reflection surface RPb is converged on the reflection surface RPb with respect to the non-scanning direction (direction of the rotation axis AXp) orthogonal to the main scanning direction (deflection direction) by the polygon mirror PM. Then, the beam LB1d reflected by the reflecting surface RPb of the polygon mirror PM is reflected toward the fθ lens FT. Regarding the direction orthogonal to the scanning direction of the polygon mirror PM, the position where the beam LBn converges on the reflection surface RPa (the position in the direction in which the rotation axis AXp extends) and the position where the beam LBn converges on the reflection surface RPb (rotation axis). The position in the direction in which AXp extends) coincides with that.

In the above embodiment, the rereflection optical system is configured by the relay lens systems G30 and G31 in FIG. 15 and the reflection mirrors M50, M51 and M52, and the same actions and effects as those in the first embodiment can be obtained. Played.

(Modification 1) FIG. 16 is a configuration diagram for reflecting the beam LBn twice on the polygon mirror PM in the modification 1 of the third embodiment (FIG. 15). The same reference numerals are given to the same configurations as those in the third embodiment. In the first modification, the beam LBn is set to the polygon mirror PM so that the reflecting surface RP of the polygon mirror PM that reflects the beam LBn the first time and the reflecting surface RP of the polygon mirror PM that reflects the beam LBn the second time are different. The configuration of the rereflection optical system incident on is different from the configuration of FIG.

The beam LB1a incident on the polygon mirror PM by a cylindrical lens having a bus in the Y direction (not shown) has a reflecting surface in a non-scanning direction (direction of rotation axis AXp) orthogonal to the main scanning direction (deflection direction) by the polygon mirror PM. It is assumed that they are converged on RPM. The beam LB1b reflected by the reflection surface RPa of the polygon mirror PM passes through the lens system G50a and then enters the reflection mirror M60. The beam LB1b reflected by the reflection mirror M60 is incident on the reflection mirror M61. The beam LB1c reflected by the reflection mirror M61 passes through the lens system G50b and is incident on the reflection surface RPb of the polygon mirror PM. This reflecting surface RPb is a reflecting surface RP different from the reflecting surface RPa. The lens systems G50a and G50b constitute a relay lens system G50 in which a pupil surface ep is formed at an intermediate position (between the reflection mirrors M60 and M61) in the optical path, and the relay lens system G50 constitutes the reflection surfaces RPa and RPb. Are in a conjugate relationship with each other. Therefore, the beam LB1c incident on the reflection surface RPb is converged on the reflection surface RPb with respect to the non-scanning direction (direction of the rotation axis AXp) orthogonal to the main scanning direction (deflection direction) by the polygon mirror PM. Then, the beam LBn reflected by the reflecting surface RPb of the polygon mirror PM is reflected toward the fθ lens FT. Regarding the direction orthogonal to the scanning direction of the polygon mirror PM, the position where the beam LB1a converges on the reflection surface RPa (the position in the direction in which the rotation axis AXp extends) and the position where the beam LBn converges on the reflection surface RPb (rotation). It coincides with the position in the direction in which the axis AXp extends). Also in the present modification 1, the same effect as that of the first embodiment can be obtained.

[Modified Examples of First to Third Embodiments]
In each of the above embodiments, the polygon mirror PM is used as the movable reflection member, but the beam LBn may be deflected by using a swing reflection member such as a galvano mirror. When a galvanometer mirror GM is used, the scanning unit U1d may be used as shown in FIG. The same components as those in the first to third embodiments are designated by the same reference numerals. Further, since the scanning units Und (U1d to U6d) have the same configuration, only the scanning unit U1d will be described as an example.

The optical axis AXf of the fθ lens FT is arranged parallel to the X axis of the Cartesian coordinate system XYZ, and the rotation (vibration) central axis Cg of the galvano mirror (movable reflection member, rocking reflection member) GM is arranged parallel to the Z axis. Will be done. The first reflecting surface m10 and the second reflecting surface m11 of the galvanometer GM are parallel to the Z axis, and at the neutral position of vibration around the rotation center axis Cg (the deflection angle is 0 degrees), the optical axis AXf of the fθ lens FT. It is set to have an angle of 45 degrees in the XY plane. This galvanometer mirror GM vibrates (oscillates) within a range of a predetermined runout angle ± θg. When the first reflecting surface m10 is, for example, the front surface of the galvano mirror GM, the second reflecting surface m 11 is the back surface of the galvano mirror GM.

The beam LB1 (hereinafter referred to as the incident beam LB1a) incident on the scanning unit U1d travels in the −Y direction after its optical path is bent by a reflection mirror or the like, and is incident on the first reflection surface m10 of the galvano mirror GM. The reflected light of the incident beam LB1a reflected by the first reflecting surface m10 of the galvano mirror GM (hereinafter, the first reflected beam LB1b) is reflected by the reflecting mirrors MRa and MRb and is incident on the galvano mirror GM again. At this time, the reflected light of the first reflected beam LB1b (hereinafter referred to as the second reflected beam LB1c) reflected by the reflecting mirrors MRa and MRb is incident on the second reflecting surface m11 of the galvano mirror GM. The reflected light of the second reflected beam LB1c reflected by the second reflecting surface m11 (hereinafter, the third reflected beam LB1d) is projected onto the substrate P as spot light SP through the fθ lens FT.

The beam scanning unit using the galvanometer mirror GM does not provide a cylindrical lens for correcting the chamfer of the reflecting surface, but when the chamfer correction is required, the incident beam is formed in a direction orthogonal to the scanning direction. An optical system including a cylindrical lens that converges each of the LB1a and the second reflection beam LB1c on the first reflection surface m10 and the second reflection surface m11 may be provided on the optical path of the beam LB. In that case, a cylindrical lens that converges the third reflection beam LB1d on the substrate P is provided between the fθ lens FT and the substrate P in a direction orthogonal to the scanning direction of the galvanometer mirror GM. According to the configuration shown in FIG. 17, even when the galvanometer mirror GM is used, the first reflection surface m10 that deflects the incident beam LB1a and the second reflection surface m11 that deflects the second reflection beam LB1c are different. Can be done. Further, since the deflection angle of the galvanometer mirror GM is ± θg, the third reflection beam LB1d deflected in the range of ± 4θg about the optical axis AXf is incident on the fθ lens FT. Therefore, even in this modified example, the same effect as that of the first embodiment can be obtained. Since the galvanometer mirror GM has poor linearity at both ends of the swing angle range, beam scanning is usually performed in a narrow swing angle range with good linearity including the central position of the vibration amplitude angle. By providing the rereflection optical member by the reflection mirrors MRa and MRb as described above, it is possible to perform beam scanning with good linearity in a wide angle range.

Claims (14)

A beam scanning device that projects a beam from a light source device deflected by a movable reflecting member that changes the angle of the reflecting surface onto an irradiated body.
The first reflected beam first reflected by the movable reflecting member is reflected to generate a second reflected beam toward the movable reflecting member, and non-deflection intersecting the deflection direction of the beam by the movable reflecting member. A rereflection optical system including a first optical member that converges the second reflected beam in terms of direction, and
A scanning optical system in which the second reflected beam is incident on the third reflected beam re-reflected by the movable reflecting member and is emitted toward the irradiated body.
The beam, which is arranged in an optical path between the movable reflection member and the scanning optical system, guides the beam from the light source device so as to first enter the movable reflection member, and is reflected again by the movable reflection member. An optical separation member that guides the third reflected beam so as to enter the scanning optical system,
A beam scanning device comprising. The beam scanning apparatus according to claim 1.
A beam scanning device in which the beam first incident on the movable reflection member and the second reflection beam incident again on the movable reflection member are set at the same position on the reflection surface of the movable reflection member with respect to the non-deflection direction. The beam scanning apparatus according to claim 2.
The movable reflective member is a rotating multifaceted mirror having a large number of reflective surfaces.
Further comprising a second optical member that converges the beam first incident on the reflecting surface of the rotating polymorphic mirror with respect to the non-deflection direction.
The scanning optical system includes an fθ lens system that incidents the third reflected beam that has been reflected again by the reflecting surface of the rotating polymorphic mirror, and the third reflected beam that is directed from the fθ lens system to the irradiated body. A beam scanning apparatus having a third optical member that converges with respect to the non-deflection direction. The beam scanning apparatus according to claim 3.
The light separating member includes a polarizing beam splitter arranged on a side in which the beam from the light source device is incident, and a wave plate arranged in an optical path between the rotating polymorphic mirror and the polarizing beam splitter.
A beam scanning device that linearly polarizes the beam that first enters the reflecting surface of the rotating polymorphic mirror. The beam scanning apparatus according to claim 4.
The first optical member is a cylindrical lens provided so that the front focal point is located on the reflecting surface of the rotating polymorphic mirror.
The rereflection optical system is a beam scanning apparatus including a reflection mirror arranged behind the cylindrical lens. The beam scanning apparatus according to claim 5.
The second optical member is a beam scanning device, which is a cylindrical lens provided so that the rear focal point is located on the reflecting surface of the rotating polymorphic mirror. A beam from a light source device is applied to each of a plurality of reflecting surfaces of a rotating multifaceted mirror rotating around a rotation axis, and a beam deflected by each of the reflecting surfaces is applied to an irradiated object via a scanning optical system. A beam scanning device that projects and scans one-dimensionally.
A first cylindrical lens that incidents the beam from the light source device and converges and irradiates it on the reflecting surface of the rotating polymorphic mirror in a non-deflection direction orthogonal to the rotation direction.
The first reflected beam first reflected by the reflecting surface of the rotating polymorphic mirror is incident to generate a second reflected beam that is reflected toward the reflecting surface of the rotating multifaceted mirror, and the second reflection is generated. A rereflection optical system including a second cylindrical lens that converges the beam on the reflection surface of the rotating polymorphic mirror with respect to the non-deflection direction.
Arranged in the optical path between the rotating polymorphic mirror and the scanning optical system, the beam from the light source device is guided so as to first enter the reflecting surface of the rotating multifaceted mirror, and the second reflected beam is introduced. A light separating member that guides a third reflected beam that is re-reflected by the reflecting surface of the rotating multi-sided mirror so as to enter the scanning optical system.
A beam scanning device comprising. The beam scanning apparatus according to claim 7.
The beam first incident on the reflecting surface of the rotating polymorphic mirror and the second reflected beam incident again are set at the same position on the reflecting surface of the rotating multifaceted mirror with respect to the non-deflection direction. Scanning device. The beam scanning apparatus according to claim 8.
The catadioptric system further includes a reflection mirror located behind the second cylindrical lens.
A beam scanning device in which the front focal point of the second cylindrical lens is set at the position of the reflecting surface of the rotating polymorphic mirror. The beam scanning apparatus according to claim 9.
The light separating member includes a polarizing beam splitter arranged on a side in which the beam from the light source device is incident, and a wave plate arranged in an optical path between the rotating multifaceted mirror and the polarizing beam splitter. A beam scanning device in which the beam first incident on the reflecting surface of the rotating polymorphic mirror is linearly polarized. With the substrate moved in a predetermined direction, the beam scanning apparatus according to any one of claims 1 to 10 is used to transmit the third reflected beam from the scanning optical system to the irradiated object. A pattern drawing device that draws a pattern on the substrate by projecting the third reflected beam onto the substrate and scanning the third reflected beam in a main scanning direction intersecting the non-deflection direction. The pattern drawing apparatus according to claim 11.
A pattern drawing device in which a plurality of beam scanning devices are arranged along at least one direction of the substrate moving direction and the main scanning direction. The pattern drawing apparatus according to claim 12.
An alignment system for detecting a predetermined mark formed on the substrate is provided.
The alignment system is a pattern drawing device provided corresponding to the positions of a plurality of beam scanning devices arranged along the moving direction of the substrate. The pattern drawing apparatus according to any one of claims 11 to 13.
The substrate is a flexible and long sheet substrate.
Further comprising a rotating drum having a central axis extending in a width direction intersecting the elongated direction of the sheet substrate and a cylindrical outer peripheral surface having a constant radius from the central axis.
The rotating drum rotates around the central axis to move the sheet substrate in the elongated direction while supporting the sheet substrate by bending a part of the sheet substrate in the elongated direction in accordance with the outer peripheral surface. ,
The beam scanning device is a pattern drawing device that projects the third reflected beam from the scanning optical system onto the sheet substrate supported by the rotating drum.

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