CN110596888B

CN110596888B - Pattern drawing device

Info

Publication number: CN110596888B
Application number: CN201910841697.8A
Authority: CN
Inventors: 铃木智也; 加藤正纪; 小宫山弘树
Original assignee: Nikon Corp
Current assignee: Nikon Corp
Priority date: 2015-03-20
Filing date: 2016-03-18
Publication date: 2022-04-01
Anticipated expiration: 2036-03-18
Also published as: JP6740999B2; KR20200024956A; KR102195908B1; JP2020194167A; CN107430272A; CN110596886A; KR20170127460A; CN110596887A; JP7074160B2; CN111638631A; WO2016152758A1; KR102169506B1; TW202024716A; CN111638631B; TW201704889A; TWI691799B; CN110596886B; TWI698662B; CN110596888A; TWI718030B

Abstract

A beam scanning device (MD) of the present invention is a beam scanning device (MD) which performs one-dimensional scanning of a spot light (SP) of a beam (LB) along a scanning line (SLn) on an irradiated surface of an object (FS) while projecting the spot light (SP) onto the irradiated surface, and the MD includes: an incident optical member (M10) for receiving a Light Beam (LB), a scanning deflection member (PM) for deflecting the Light Beam (LB) from the incident optical member (M10) for scanning, a projection optical system (FT) for receiving the deflected Light Beam (LB) and projecting the same onto an irradiated surface, and a support frame (40) for supporting the incident optical member (M10), the scanning deflection member (PM) and the projection optical system (FT), and being rotatable about a 1 st rotation center axis (Mrp) coaxial with an irradiation center axis (Le) passing perpendicularly to the irradiated surface through a midpoint of a scanning line (SLn) formed on the irradiated surface by scanning of the spot light (SP).

Description

Pattern drawing device

The present application is filed as a divisional application, and has an application number of 201680017014.1(PCT/JP2016/058644), application date of 2016, 03, and 18, entitled "light beam scanning apparatus, light beam scanning method, and drawing apparatus".

Technical Field

The present invention relates to a light beam scanning device, a light beam scanning method, and a drawing device for scanning a spot light of a light beam irradiated on an irradiated surface of an object to draw a predetermined pattern.

Background

Conventionally, as a high-speed printer for business use, it is known that while a spot light of a laser beam is projected onto an object to be irradiated (an object) such as a photoreceptor drum, one-dimensional main scanning of the spot light is performed along a main scanning line by a rotary polygon mirror, and the object to be irradiated is moved in a sub-scanning direction orthogonal to the main scanning line direction to draw a desired pattern or image (characters, figures, photographs, etc.) on the object to be irradiated.

In Japanese patent laid-open No. 8-11348, there is disclosed an optical beam scanning device for adjusting the tilt of a main scanning line of an optical beam. The optical beam scanning device described in japanese patent application laid-open No. 8-11348 includes a plate inclined in the direction of irradiation of the optical beam, and an optical unit mounted on the plate, and the plate is mounted on the main body. By rotating the plate relative to the main body in the main scanning direction, the optical unit is rotated to adjust the inclination of the main scanning line. Because of this adjustment, the lengths of both sides of the midpoint of the main scanning line become different, and thus the lengths of both sides of the midpoint of the main scanning line are adjusted to be equal by rotating the optical unit relative to the plate in the main scanning direction. The two-dimensional positional shift of the scanning line itself or the magnification error in the main scanning line direction is corrected by adjusting the distance from the photosensitive body of the optical unit or by electrically controlling the writing timing along the main scanning line. The optical unit integrally includes a light source that emits a light beam modulated for drawing, a collimator lens that converts the light beam into parallel light, a rotary polygonal mirror, and an f θ lens.

However, in japanese patent application laid-open No. 8-11348, since the optical unit is rotated about a position away from the main scanning line, it is necessary to perform multi-stage adjustment (adjustment of rotation of the plate with respect to the main body, adjustment of rotation of the optical unit with respect to the plate, adjustment of the distance of the optical unit from the photoreceptor, correction of the writing timing of the drawing, and the like) in order to adjust the inclination of the main scanning line. In particular, in an optical beam scanning device for electronic components that uses spot light of an ultraviolet beam having a wavelength of 400nm or less to precisely draw a pattern having a minimum width of several μm to several tens of μm, since the inclination of a scanning line (the inclination of a main scanning line direction with respect to a direction orthogonal to a sub-scanning direction) is finely adjusted during the drawing of the pattern, it is desirable to easily adjust the inclination of the scanning line. The present invention can solve the above problem.

Disclosure of Invention

A light beam scanning device according to a 1 st aspect of the present invention is a light beam scanning device for performing one-dimensional scanning of a spot light of a light beam from a light source device on an irradiation target surface of an object while projecting the spot light on the irradiation target surface, the light beam scanning device including: an incident optical member for the light beam from the light source device to be incident; a scanning deflecting member for deflecting the light beam from the incident optical member for the one-dimensional scanning; a projection optical system for projecting the deflected light beam onto the irradiated surface after incidence; and a support frame which supports the incident optical member, the scanning deflection member, and the projection optical system and is rotatable about a 1 st rotation center axis which is coaxial within a predetermined allowable range with respect to an irradiation center axis which passes perpendicularly to the surface to be irradiated through a specific point on a scanning line formed on the surface to be irradiated by scanning of the spot light.

A light beam scanning device according to a 2 nd aspect of the present invention is a light beam scanning device for performing one-dimensional scanning of a spot light of a light beam from a light source device on an irradiation target surface of an object while irradiating the spot light on the irradiation target surface, the light beam scanning device including: an incident optical member for the light beam from the light source device to be incident; a scanning deflecting member for deflecting the light beam from the incident optical member for the one-dimensional scanning; a projection optical system for projecting the deflected light beam onto the irradiated surface after incidence; and an image rotating optical system provided between the irradiated surface and the projection optical system, for rotating a scanning line formed on the irradiated surface by scanning of the spot light around a rotation center axis coaxial within a predetermined allowable range with respect to an irradiation center axis passing through a specific point on the scanning line perpendicularly to the irradiated surface.

A light beam scanning method according to aspect 3 of the present invention is a light beam scanning method for performing one-dimensional scanning of a spot light of a light beam from a light source device on an irradiation surface of an object while projecting the spot light onto the irradiation surface using a light beam scanning device, the light beam scanning method including: an incident step of causing the light beam from the light source device to be incident on the light beam scanning device; a deflecting step of deflecting the incident light beam for the one-dimensional scanning; a projection step of projecting the deflected light beam onto the irradiated surface after the light beam is incident thereon; and a rotation step of rotating a scanning line formed on the irradiation surface by the scanning of the spot light around a rotation center axis, the rotation center axis being coaxial within a predetermined allowable range with respect to an irradiation center axis passing through a specific point on the scanning line perpendicularly to the irradiation surface.

A drawing device according to a 4 th aspect of the present invention is a drawing device for performing one-dimensional scanning of a spot light of a light beam from a light source device on an irradiation target surface of an object while projecting the spot light on the irradiation target surface, the drawing device including: an incident optical member for the light beam from the light source device to be incident; a scanning deflecting member for deflecting the light beam from the incident optical member for the one-dimensional scanning; a projection optical system for projecting the deflected light beam onto the irradiated surface after incidence; a support frame for supporting the incident optical member, the scanning deflection member, and the projection optical system; a rotation support mechanism for supporting the support frame on the apparatus main body in a state of being rotatable around a 1 st rotation center axis parallel to a normal line of the surface to be irradiated; and a light introduction optical system for guiding the light beam from the light source device to the incident optical member such that an incident axis of the light beam incident on the incident optical member is coaxial with the 1 st rotation center axis within a predetermined allowable range.

A drawing device according to a 5 th aspect of the present invention is a drawing device for performing one-dimensional scanning of a spot light of a light beam from a light source device on an irradiation target surface of an object while projecting the spot light on the irradiation target surface, the drawing device including: a scanning deflection member for deflecting the light beam from the light source device for the one-dimensional scanning; a projection optical system for projecting the deflected light beam onto the irradiated surface after incidence; a support frame for supporting the deflection member for scanning and the projection optical system; and a coupling member that couples the support frame and the apparatus main body such that a portion of the support frame supporting the apparatus main body is limited to an area within a predetermined radius from the irradiation center axis, when a normal line of the irradiation target surface to a specific point on a scanning line formed on the irradiation target surface by scanning of the spot light is set as the irradiation center axis.

A light beam scanning device according to a 6 th aspect of the present invention is a light beam scanning device for performing one-dimensional scanning of a spot light while converging a light beam projected onto an irradiation surface of an object on the irradiation surface into the spot light, the light beam scanning device including: a deflection member for reflecting the incident beam and deflecting the reflected beam within a predetermined angle range to scan the spot light; a light transmitting optical system for directing the incident light beam toward the deflecting member; and a projection optical system for projecting the incident beam from the light-transmitting optical system to the deflecting member after incidence, and projecting the spot light of the reflected beam to the irradiated surface after incidence of the reflected beam.

A drawing device according to claim 7 of the present invention is a drawing device that performs one-dimensional scanning of a light beam projected onto an irradiation surface of an object to draw a predetermined pattern, the drawing device including: a deflection member deflecting the light beam for one-dimensional scanning; a light transmitting optical system for allowing the light beam from the light source device to enter and direct the light beam toward the deflecting member; and a projection optical system that projects the light beam from the light transmission optical system after entering the deflection member and projects the light beam reflected by the deflection member onto the irradiated surface.

A drawing device according to an 8 th aspect of the present invention is a drawing device that repeatedly scans a light beam for drawing projected onto an irradiation object by rotation of a rotating polygon mirror to draw a predetermined pattern on the irradiation object, the drawing device including: an origin detection unit that generates an origin signal when detecting that a 2 nd reflection surface, which is different from a 1 st reflection surface that reflects the drawing light beam, among the plurality of reflection surfaces of the rotary polygon mirror is at a predetermined angular position; and a control device for instructing the start of drawing with the drawing light beam at a timing delayed from the generation of the origin signal by a predetermined time determined by the rotational speed of the rotary polygon mirror until the 2 nd reflecting surface becomes the 1 st reflecting surface after the generation of the origin signal.

Drawings

Fig. 1 is a schematic configuration diagram of a device manufacturing system including an exposure apparatus that performs exposure processing on a substrate according to an embodiment.

Fig. 2 is a view showing the rotary drum of fig. 1 with the substrate wound thereon in detail.

Fig. 3 is a diagram showing a drawing line of the spot light and the alignment mark formed on the substrate.

Fig. 4 is an enlarged view of a main part of the exposure apparatus of fig. 1.

Fig. 5 is a diagram showing in detail an optical configuration of the light introduction optical system of fig. 4.

Fig. 6 is a schematic explanatory view for explaining the optical path switching by the optical element for drawing of fig. 5.

Fig. 7 is a diagram of an optical configuration of the optical beam scanning device of fig. 4.

Fig. 8 is a diagram showing a configuration of an origin sensor provided around the polygon mirror of fig. 7.

FIG. 9 is a diagram showing a relationship between a generation timing of an origin signal and a trace start timing.

Fig. 10 is a sectional view showing a holding structure of the optical beam scanning device constituted by the 2 nd frame portion of fig. 4.

Fig. 11 is a cross-sectional view taken along line XI-XI of fig. 10.

Fig. 12 is a perspective view showing a structure for holding the plurality of optical beam scanning devices shown in fig. 4 and fig. 10 and 11.

Fig. 13 is a perspective view showing a mounting structure of the structure and the main body of the exposure apparatus shown in fig. 12.

FIG. 14 is a view showing a deformed state of an exposure region where a predetermined pattern is exposed by the exposure head of FIG. 4.

Fig. 15 is a diagram showing an optical configuration of the optical beam scanning device according to modification 1.

Fig. 16 is a diagram showing an optical configuration of the optical beam scanning device according to modification 2.

Fig. 17A is a view of the optical configuration of the optical beam scanning device according to modification 4 as viewed in a plane parallel to the XtZt plane, and fig. 17B is a view of the optical configuration of the optical beam scanning device according to modification 4 as viewed in a plane parallel to the YtZt plane.

Fig. 18A is a view of the optical configuration of the optical beam scanning device according to modification 5 as viewed in a plane parallel to the XtYt plane, and fig. 18B is a view of the optical configuration of the optical beam scanning device according to modification 5 as viewed in a plane parallel to the YtZt plane.

Fig. 19 is a diagram showing an optical configuration of an optical beam scanning device according to modification 6.

Fig. 20 is a diagram showing a configuration in a case where a plurality of the optical beam scanning apparatuses of fig. 19 are arranged.

Fig. 21 is a diagram for explaining a drawing position error when a drawing line formed by the optical beam scanning device is tilted.

Fig. 22 is a diagram for explaining a drawing position error when a drawing line is tilted in the case where the rotation center of the optical beam scanning apparatus is shifted.

Fig. 23 is a diagram showing the configuration of the optical beam scanning device according to embodiment 2.

Detailed Description

The optical beam scanning device, the optical beam scanning method, and the drawing device according to the embodiments of the present invention will be described in detail below with reference to the accompanying drawings. The aspect of the present invention is not limited to the embodiments, and various changes and modifications may be made. That is, the following constituent elements include those which can be easily found by a person skilled in the art and substantially the same, and may be appropriately combined. Various omissions, substitutions, and changes in the components may be made without departing from the spirit of the invention.

Fig. 1 is a schematic configuration diagram of a device manufacturing system 10 including an exposure apparatus EX for performing an exposure process on a substrate (irradiation target object) FS according to an embodiment. In the following description, unless otherwise specified, an XYZ rectangular coordinate system in which the direction of gravity is the Z direction is set, and the X direction, the Y direction, and the Z direction are described with reference to arrows shown in the drawings.

The device manufacturing system 10 is constructed, for example, as a manufacturing system for manufacturing a manufacturing line for manufacturing a flexible display, a flexible wiring, a flexible sensor, and the like as electronic devices. Hereinafter, a flexible display as an electronic device will be described as a premise. Examples of the flexible display include an organic EL display and a liquid crystal display. The component manufacturing system 10 has a so-called Roll-To-Roll (Roll To Roll) system in which a flexible sheet substrate (sheet substrate) FS is wound into a Roll and a supply Roll-out substrate FS (not shown) is fed out, and after various kinds of processing are continuously applied To the fed-out substrate FS, the substrate FS after various kinds of processing is wound into a recovery Roll (not shown). The substrate FS has a belt-like shape with the moving direction of the substrate FS being the long side direction (long) and the width direction being the short side direction (short). The substrate FS after various treatments is a substrate that can be used for many surfaces, in which a plurality of electronic components are connected in the longitudinal direction. The substrate FS fed from the supply reel is subjected to various processes in this order by the processing apparatus PR1, the exposure apparatus EX, the processing apparatus PR2, and the like, and then wound up by the take-up reel.

The X direction is a direction (conveyance direction) from the processing apparatus PR1 to the processing apparatus PR2 through the exposure apparatus EX in the horizontal plane. The Y direction is a direction orthogonal to the X direction in the horizontal plane, and is a width direction (short side direction) of the substrate FS. The Z direction is a direction (upward direction) orthogonal to the X direction and the Y direction, and is parallel to the direction in which gravity acts.

The substrate FS is, for example, a foil (foil) made of a metal such as a resin film or stainless steel or an alloy thereof. As the material of the resin film, for example, at least one or more materials including polyethylene resin, polypropylene resin, polyester resin, ethylene-vinyl copolymer resin, polyvinyl chloride resin, cellulose resin, polyamide resin, polyimide resin, polycarbonate resin, polystyrene resin, vinyl acetate resin, and the like can be used. The thickness and rigidity (young's modulus) of the substrate FS may be set to a range within which no fold or irreversible wrinkles due to bending are generated in the substrate FS when the substrate FS passes through the transfer path of the exposure apparatus EX. A film of PET (polyethylene terephthalate), PEN (polyethylene naphthalate), or the like having a thickness of about 25 to 200 μm is a typical base material of the substrate FS, which is a very suitable sheet substrate.

Since the substrate FS is heated in each process performed by the processing apparatus PR1, the exposure apparatus EX, and the processing apparatus PR2, it is preferable to select a substrate FS having a thermal expansion coefficient that does not significantly increase. For example, the coefficient of thermal expansion can be suppressed by mixing an inorganic filler with the resin film. The inorganic filler may be, for example, titanium oxide, zinc oxide, aluminum oxide, silicon oxide, or the like. The substrate FS may be a single-layer body of an extra thin glass having a thickness of about 100 μm manufactured by a float method or the like, or a laminate body in which the above-mentioned resin film, foil, or the like is laminated on the extra thin glass.

The flexibility of the substrate FS means that the substrate FS can be flexed without being sheared or broken even when a force of a certain weight is applied to the substrate FS. Flexibility also includes the property of bending due to forces of the degree of its own weight. The degree of flexibility varies depending on the material, size, and thickness of the substrate FS, the layer structure formed on the substrate FS, and the environment such as temperature and humidity. In any case, the flexibility is within a range that allows the substrate FS to be smoothly transported without being folded and creased or damaged (causing holes or cracks) when the substrate FS is accurately wound around a transport direction changing member such as various transport reels or rotary drums in the transport path provided in the device manufacturing system 10 of the present embodiment.

The processing apparatus PR1 performs a pre-process on the substrate FS subjected to the exposure process by the exposure apparatus EX. The processing apparatus PR1 sends the processed substrate FS subjected to the previous process to the exposure apparatus EX. By the treatment in the foregoing process, the substrate FS transferred to the exposure apparatus EX becomes a substrate (photosensitive substrate) FS on the surface of which a photosensitive functional layer (photosensitive layer) is formed.

The photosensitive functional layer is applied as a solution onto the substrate FS and dried to form a layer (film). Typical examples of the photosensitive functional layer include a photoresist (liquid or dry film form) as a material not requiring development treatment, a photosensitive silane coupling agent (SAM) modified in lyophilicity in a portion irradiated with ultraviolet rays, and a photosensitive reducing material in which a reducing group is exposed in a portion irradiated with ultraviolet rays. When a photosensitive silane coupling agent is used as the photosensitive functional layer, the pattern portion exposed to ultraviolet light on the substrate FS is modified from liquid repellency to lyophilic. Therefore, a conductive ink (ink containing conductive nanoparticles such as silver or copper) or a liquid containing a semiconductor material can be selectively applied to the lyophilic portion to form an electrode constituting a Thin Film Transistor (TFT), a semiconductor, an insulating layer, or a pattern layer serving as a connection wiring or an electrode. When a photosensitive reducing element is used as the photosensitive functional layer, the plating reducing element is exposed at the pattern portion exposed to ultraviolet light on the substrate FS. Therefore, immediately after the exposure, the substrate P is immersed in a plating solution containing palladium ions or the like for a certain period of time to form (precipitate) a pattern layer of palladium. When such plating treatment is based on an etching treatment as an additive (additive) type treatment or a subtractive (subtractive) type treatment, the substrate FS fed to the exposure apparatus EX may be a base material of PET or PEN, on the entire surface of which a metal thin film of aluminum (Al), copper (Cu), or the like is selectively deposited, and a photoresist layer may be laminated thereon.

In the present embodiment, the exposure apparatus EX is an exposure apparatus of a direct writing system without using a mask, a so-called line-by-line scanning (raster scan) system, and corresponds to a light pattern for forming a predetermined pattern of display electronic elements, circuits, wirings, and the like on an irradiated surface (light-receiving surface) of the substrate FS supplied from the processing apparatus PR 1. The exposure apparatus EX performs one-dimensional scanning (main scanning) in a predetermined scanning direction (Y direction) ON the surface to be irradiated of the substrate FS with spot light SP of exposure light beam LB while conveying the substrate FS in the + X direction (sub-scanning direction), and modulates (ON/OFF) the intensity of the spot light SP at high speed based ON pattern data (drawing data), as will be described later in detail. Accordingly, a light pattern corresponding to a predetermined pattern of electronic elements, circuits, wirings, and the like is drawn and exposed on the irradiated surface of the substrate FS. That is, the sub-scanning of the substrate FS and the main scanning of the spot light SP are transmitted, and the spot light SP is two-dimensionally scanned so as to face the irradiated surface of the substrate FS, thereby drawing and exposing the substrate FS with a predetermined pattern. In addition, since the electronic device is formed by stacking a plurality of pattern layers (layers having patterns formed thereon), the patterns corresponding to the respective layers are exposed by the exposure apparatus EX.

The processing apparatus PR2 performs post-process processing (for example, plating, development, etching, and the like) on the substrate FS subjected to the exposure processing by the exposure apparatus EX. By the subsequent processes, a pattern layer of an electronic device is formed on the substrate FS. Further, since the electronic component is constituted by overlapping a plurality of pattern layers, after the pattern is formed on the 1 st layer by each process of the component manufacturing system 10, the pattern is formed on the 2 nd layer by each process of the component manufacturing system 10 again.

Next, the exposure apparatus EX will be described in detail. The exposure apparatus EX is housed in a temperature-controlled room ECV. The temperature control chamber ECV keeps the inside at a predetermined temperature, thereby suppressing the shape change of the substrate FS conveyed inside due to the temperature. The temperature control chamber ECV is disposed on a mounting surface E of a manufacturing plant through passive or active vibration control units SU1, SU 2. The vibration isolation units SU1 and SU2 reduce vibration from the installation surface E. The installation surface E may be the floor of a factory or may be a surface on an installation base (pedestal) installed on the floor to form a horizontal surface. The exposure apparatus EX includes at least a substrate conveyance mechanism 12, a light source device (pulse light source device) 14, an exposure head 16, a control device 18, and a plurality of alignment microscopes ALG (ALG1 to ALG 4).

The substrate transfer mechanism 12 transfers the substrate FS transferred from the processing apparatus PR1 at a predetermined speed in the exposure apparatus EX, and then, transfers the substrate FS at a predetermined speed to the processing apparatus PR 2. The substrate transfer mechanism 12 defines a transfer path of the substrate FS transferred in the exposure apparatus EX. The substrate conveyance mechanism 12 includes, in order from the upstream side (the (-X direction side) in the conveyance direction of the substrate FS, an edge position controller EPC, a drive roller R1, a tension adjustment roller RT1, a rotary drum (cylinder) DR, a tension adjustment roller RT2, a drive roller R2, and a drive roller R3.

The edge position controller EPC adjusts the position of the substrate FS transferred from the processing apparatus PR1 in the width direction (Y direction, short side direction of the substrate FS). That is, the edge position controller EPC adjusts the position of the substrate FS in the width direction by moving the substrate FS in the width direction so that the position of the end (edge) of the substrate FS in the width direction, which is conveyed in a state of a predetermined tension, can be controlled to a range (allowable range) of about ± ten μm to several tens μm with respect to the target position. The edge position controller EPC includes a roller on which the substrate FS is hung, and an edge sensor (edge detection unit), not shown, which detects the position of an edge (edge) of the substrate FS in the width direction, and adjusts the position of the substrate FS in the width direction by moving the roller of the edge position controller EPC in the Y direction based on a detection signal detected by the edge sensor. The drive roller R1 rotates while holding both front and back surfaces of the substrate FS transferred from the edge position controller EPC, and transfers the substrate FS to the rotary drum DR. The edge position controller EPC can correct the position of the substrate FS in the width direction and the tilt error of the substrate FS in the traveling direction by appropriately adjusting the parallelism between the rotation axis of the roller of the edge position controller EPC and the Y axis so that the longitudinal direction of the substrate FS wound around the spin basket DR is constantly orthogonal to the center axis AXo of the spin basket DR.

The rotary drum DR has a center axis AXo extending in the Y direction and extending in a direction intersecting the Z direction in which gravity acts, and a cylindrical outer peripheral surface having a constant radius from the center axis AXo, and rotates about the center axis AXo while supporting a part of the substrate FS in the longitudinal direction along the outer peripheral surface (circumferential surface) to convey the substrate FS in the + X direction. The rotary drum DR supports an exposure area (portion) on the substrate FS projected by the beam LB (spot beam SP) from the exposure head 16 with the peripheral surface. On both sides of the rotary drum DR in the Y direction, shafts Sft supported by ring bearings so as to rotate around the center shaft AXo are provided. The shaft Sft is rotated around the center axis AXo by a rotational torque applied thereto from a not-shown rotational drive source (e.g., a motor, a reduction mechanism, or the like) controlled by the control device 18. For convenience, a plane parallel to the YZ plane including the central axis AXo is referred to as a central plane Poc.

The drive rollers R2 and R3 are disposed at a predetermined interval in the conveyance direction (+ X direction) of the substrate FS, and apply a predetermined slack to the exposed substrate FS. The drive rollers R2 and R3 rotate while holding both front and back surfaces of the substrate FS, similarly to the drive roller R1, and convey the substrate FS to the processing apparatus PR 2. The drive rollers R2 and R3 are provided on the downstream side (+ X direction side) in the conveyance direction with respect to the rotary drum DR, and the drive roller R2 is provided on the upstream side (-X direction side) in the conveyance direction with respect to the drive roller R3. The tension adjusting rollers RT1 and RT2 are urged in the-Z direction, and apply a predetermined tension to the substrate FS wound around and supported by the rotary drum DR in the longitudinal direction. Accordingly, the tension in the longitudinal direction applied to the substrate FS and acting on the rotary drum DR is stabilized within a predetermined range. The controller 18 controls a rotation driving source (e.g., a motor, a reduction gear, or the like), not shown, to rotate the driving rollers R1 to R3.

The light source device 14 has a light source (pulse light source) and emits a pulse-shaped light beam (pulse light, laser light) LB. The light beam LB is ultraviolet light having a peak wavelength in a wavelength band of 370nm or less, and the emission frequency of the light beam LB is Fe. The light beam LB emitted from the light source device 14 is incident on the exposure head 16. The light source device 14 oscillates the light beam LB at the light emitting frequency Fe and emits the light beam LB under the control of the control device 18. As the light source device 14, a fiber-amplified laser light source including a semiconductor laser element that emits a pulse light in an infrared wavelength band, a fiber amplifier, a wavelength conversion element (harmonic generation element) that converts the amplified pulse light in the infrared wavelength band into a pulse light in an ultraviolet wavelength band, and the like can be used. In this case, a high-luminance ultraviolet pulsed light having an emission frequency (oscillation frequency) Fe of several hundreds MHz and an emission time of 1 pulsed light of picoseconds can be obtained.

The exposure head 16 includes a plurality of beam scanning devices MD (MD1 to MD6) to which the beams LB are incident, respectively. The exposure head 16 draws a predetermined pattern on a part of the substrate FS supported by the circumferential surface of the rotary drum DR by a plurality of beam scanning devices MD1 to MD 6. The exposure head 16 is a so-called multi-beam type exposure head in which a plurality of beam scanning devices MD1 to MD6 having the same configuration are arranged. Since the exposure head 16 repeatedly performs pattern exposure for the electronic components on the substrate FS, a plurality of exposure areas W (1 electronic component formation area) for exposing the pattern are provided at predetermined intervals in the longitudinal direction of the substrate FS (see fig. 3).

As shown in fig. 2, the odd-numbered beam scanning devices (beam scanning units) MD1, MD3, and MD5 are arranged upstream (on the X direction side) in the conveyance direction of the substrate FS with respect to the center plane Poc and are arranged in parallel in the Y direction. The even-numbered beam scanning devices (beam scanning units) MD2, MD4, and MD6 are arranged on the downstream side (+ X direction side) in the conveyance direction of the substrate FS with respect to the center plane Poc and are arranged in parallel in the Y direction. The odd-numbered beam scanning devices MD1, MD3, and MD5 and the even-numbered beam scanning devices MD2, MD4, and MD6 are disposed symmetrically with respect to the center plane Poc.

The beam scanning device MD performs one-dimensional scanning along a predetermined straight line drawing line SLn on the surface to be irradiated of the substrate FS with the spot light SP while projecting the beam LB from the light source device 14 so as to converge the spot light SP on the surface to be irradiated of the substrate FS. As shown in fig. 2 and 3, the scanning lines (scanning lines) SLn of the plurality of beam scanning devices MD1 to MD6 are set so as to be joined without being separated from each other in the Y direction (the width direction and the scanning direction of the substrate FS). Hereinafter, the light beam LB incident on each of the beam scanning devices MD (MD1 to MD6) may be referred to as LB1 to LB 6. The light beams LB (LB1 to LB6) incident on the respective beam scanning devices MD (MD1 to MD6) are linearly polarized light beams (P-polarized light or S-polarized light) polarized in a predetermined direction, and in the present embodiment, are incident P-polarized light beams. The drawing line SLn of the beam scanning device MD1 may be referred to as SL1, and the drawing lines SLn of the beam scanning devices MD2 to MD6 may be referred to as SL2 to SL 6.

As shown in fig. 3, the scanning regions are shared by the respective beam scanning devices MD (MD1 to MD6) so that all of the plurality of beam scanning devices MD1 to MD6 cover the entire width direction of the exposure region W. Accordingly, the beam scanning devices MD (MD1 to MD6) can draw a pattern in each of a plurality of regions divided in the width direction of the substrate FS. For example, if the Y-direction scanning width (the length of the scanning line SLn) of 1 beam scanning device MD is about 30 to 60mm, a total of 6 beam scanning devices MD are arranged in the Y direction by 3 odd-numbered beam scanning devices MD1, MD3, and MD5 and 3 even-numbered beam scanning devices MD2, MD4, and MD6, and the Y-direction width that can be drawn is extended to about 180 to 360 mm. The lengths of the drawing lines SL1 to SL6 are basically the same. That is, the scanning distances of the spot light SP of the light beam LB scanned along the drawing lines SL1 to SL6 are the same.

The actual drawing lines SLn (SL1 to SL6) are set to be slightly shorter than the maximum length of the spot light SP that can actually scan the irradiated surface. For example, when the maximum length of the drawing line SLn that can be pattern-drawn at the initial value (no magnification correction) of the drawing magnification in the main scanning direction (Y direction) is 50mm, the maximum scanning length of the spot light SP on the irradiated surface is set to about 51mm so that the scanning start point side and the scanning end point side of the drawing line SLn have a margin of about 0.5 mm. With this setting, the position of the drawing line SLn of 50mm can be finely adjusted in the main scanning direction or the drawing magnification can be finely adjusted within the range of the maximum scanning length 51mm of the spot light SP.

The drawing lines SL1 to SL6 are arranged in 2 rows in the circumferential direction of the rotary drum DR with the center plane Poc therebetween. The odd-numbered drawing lines SL1, SL3, and SL5 are located on the irradiated surface of the substrate FS on the upstream side (the (-X direction side) in the conveyance direction of the substrate FS with respect to the center plane Poc. The even drawing lines SL2, SL4, and SL6 are located on the irradiated surface of the substrate FS on the downstream side (+ X direction side) in the conveyance direction of the substrate FS with respect to the center plane Poc. The drawing lines SL1 to SL6 are substantially parallel to the width direction of the substrate FS, that is, along the central axis AXo of the rotary drum DR.

The scanning lines SL1, SL3, and SL5 are arranged on a straight line with a predetermined interval in the width direction (scanning direction) of the substrate FS. Similarly, the scanning lines SL2, SL4, and SL6 are arranged on a straight line with a predetermined interval in the width direction (scanning direction) of the substrate FS. At this time, the drawing line SL2 is arranged between the drawing line SL1 and the drawing line SL3 in the width direction of the substrate FS. Similarly, the drawing line SL3 is disposed between the drawing line SL2 and the drawing line SL4 in the width direction of the substrate FS. The drawing line SL4 is disposed between the drawing lines SL3 and SL5 in the width direction of the substrate FS, and the drawing line SL5 is disposed between the drawing lines SL4 and SL6 in the width direction of the substrate FS.

The scanning directions of the spot light SP of the light beam LB scanned along the odd-numbered drawing lines SL1, SL3, and SL5 are one-dimensional directions and the same direction. The scanning directions of the spot light SP of the light beam LB scanned along the even-numbered drawing lines SL2, SL4, and SL6 are one-dimensional directions and the same direction. The scanning direction of the spot light SP of the light beam LB scanned along the drawing lines SL1, SL3, and SL5 and the scanning direction of the spot light SP of the light beam LB scanned along the drawing lines SL2, SL4, and SL6 are opposite to each other. Specifically, the scanning direction of the spot light SP of the light beam LB scanned along the drawing lines SL1, SL3, and SL5 is the-Y direction, and the scanning direction of the spot light SP of the light beam LB scanned along the drawing lines SL2, SL4, and SL6 is the + Y direction. Accordingly, the drawing start positions (positions of the drawing start points) of the drawing lines SL1, SL3, and SL5 are adjacent to (or partially overlap) the drawing start positions of the drawing lines SL2, SL4, and SL6 in the Y direction. The drawing end positions (drawing end points) of the drawing lines SL3 and SL5 and the drawing end positions of the drawing lines SL2 and SL4 are adjacent to (or partially overlap) each other in the Y direction. When the end portions of the drawing lines SLn adjacent in the Y direction are partially overlapped with each other, for example, the overlapping of the drawing start position or the drawing end position in the Y direction by a range of several% or less may be included with respect to the length of each drawing line SLn.

The width of the scanning line SLn in the sub-scanning direction corresponds to the size (diameter) of the spot light SP

The thickness of (2). For example, the size of the spot light SP

At 3 μm, the width of each trace line SLn is also 3 μm. The spot light SP may have a predetermined length (for example, the size of the spot light SP)

Half of the drawing line) along the drawing line SLn. When the drawing lines SLn adjacent to each other in the Y direction (for example, the drawing lines SL1 and SL2) are adjacent to each other (joined together), the drawing lines SLn may have only a predetermined length (for example, the size of the spot light SP)

Half) overlap is preferred.

In the case of the present embodiment, since the light beam LB from the light source device 14 is pulsed light, the spot light SP projected on the drawing line SLn between main scans is dispersed in response to the oscillation frequency Fe of the light beam LB. Therefore, it is necessary to makeThe spot light SP projected by the 1 pulse light of the light beam LB and the next spot light SP projected by the 1 pulse light overlap each other in the main scanning direction (overlap). The amount of the overlap is determined by the size of the spot light SP

The scanning speed of the spot light SP and the oscillation frequency Fe of the beam LB are set so that when the intensity distribution of the spot light SP is approximated to a Gaussian distribution, the scanning speed is set to be equal to the effective diameter size determined at 1/e2 (or 1/2) of the peak intensity of the spot light SP

Make them overlap

The degree is preferred. Therefore, it is preferable that the substrate FS is moved by the effective size of the spot light SP between one scan and the next scan of the spot light SP along the drawing line SLn in the sub-scanning direction (the direction orthogonal to the drawing line SLn)

Approximately 1/2 or less. The amount of exposure of the photosensitive functional layer on the substrate FS can be set by adjusting the peak value of the beam LB (pulsed light), but when the amount of exposure is to be increased without increasing the intensity of the beam LB, the amount of overlap of the spot light SP in the main scanning direction or the sub-scanning direction can be increased to an effective size by any of decreasing the scanning speed of the spot light SP in the main scanning direction, increasing the oscillation frequency Fe of the beam LB, and decreasing the conveyance speed of the substrate FS in the sub-scanning direction

Above 1/2.

The beam scanning apparatuses MD (MD1 to MD6) irradiate the substrate FS with the beams LB (LB1 to LB6) so that the beams LB (LB1 to LB6) are perpendicular to the irradiated surface of the substrate FS at least in the XZ plane. That is, each of the beam scanning apparatuses MD (MD1 to MD6) irradiates (projects) the substrate FS with the beam LB (LB1 to LB6) so as to travel toward the central axis AXo of the rotating cylinder DR in the XZ plane, that is, so as to be coaxial (parallel) to the normal line of the irradiated surface. Further, the beam scanning apparatuses MD (MD1 to MD6) irradiate the substrate FS with the beams LB (LB1 to LB6) so that the beams LB (LB1 to LB6) irradiated on the drawing lines SLn (SL1 to SL6) are perpendicular to the irradiated surface of the substrate FS in a plane parallel to the YZ plane. That is, in the main scanning direction of the spot light SP on the irradiated surface, the luminous fluxes LB (LB1 to LB6) projected on the substrate FS are scanned in a telecentric state. Here, a line (also referred to as an optical axis) perpendicular to the surface to be irradiated of the substrate FS and passing through a midpoint (center point) of the drawing line SLn (SL1 to SL6) defined by the respective beam scanning apparatuses MD (MD1 to MD6) is referred to as an irradiation central axis Le (Le1 to Le 6).

The irradiation central axes Le1 to Le6 are lines connecting the drawing lines SL1 to SL6 and the central axis AXo on the XZ plane. The irradiation central axes Le1, Le3, Le5 of the odd-numbered beam scanning devices MD1, MD3, MD5 are in the same direction on the XZ plane, and the irradiation central axes Le2, Le4, Le6 of the odd-numbered beam scanning devices MD2, MD4, MD6 are in the same direction on the XZ plane. In the XZ plane, the irradiation center axes Le1, Le3, Le5 and the irradiation center axes Le2, Le4, Le6 are set to have an angle ± θ with respect to the center plane Poc (see fig. 4).

As shown in fig. 2, at both ends of the rotary drum DR, scale portions SD (SDa, SDb) having scale marks formed in a ring shape are provided on the entire outer circumferential surface of the rotary drum DR. The scale unit SD (SDa, SDb) is a diffraction grating in which concave or convex grid lines are engraved at a constant pitch (for example, 20 μm) in the circumferential direction of the outer peripheral surface of the rotary drum DR, and is configured as an incremental scale. The scale portion SD (SDa, SDb) rotates integrally with the rotary drum DR about the central axis AXo. Further, a plurality of encoders (scale reading heads) EC are provided so as to face the scale portions SD (SDa, SDb). The encoder EC optically detects the rotational position of the rotary drum DR. 2 encoders EC (EC1a, EC2a) are provided facing a scale portion SDa provided at the end of the rotary drum DR in the-Y direction, and 2 encoders EC (EC1b, EC2b) are provided facing a scale portion SDb provided at the end of the rotary drum DR in the + Y direction.

The encoders EC (EC1a, EC1b, EC2a, EC2b) project measuring light beams onto the scale portions SD (SDa, SDb) and photoelectrically detect reflected light beams (diffracted light), thereby outputting detection signals corresponding to circumferential position changes of the scale portions SD (SDa, SDb) to the control device 18. The controller 18 performs digital processing by inserting the detection signal into the inner row by a not-shown counting circuit, and measures the angular change of the rotary drum DR, that is, the circumferential position change of the outer peripheral surface thereof with a sub-micron resolution. The controller 18 may measure the transfer speed of the substrate FS from the change in the angle of the rotary drum DR.

The encoders EC1a and EC1b are provided on the upstream side (on the side of the X direction) of the conveyance direction of the substrate FS with respect to the center plane Poc, and are arranged on the same line as the irradiation center axes Le1, Le3, and Le5 in the XZ plane. That is, on the XZ plane, a line connecting the projection positions (reading positions) of the measuring beams projected from the encoders EC1a, EC1b on the scale portions SDa, SDb and the central axis AXo is arranged on the same line as the irradiation central axes Le1, Le3, Le 5. Similarly, the encoders EC2a and EC2b are provided on the downstream side (+ X direction side) of the conveyance direction of the substrate FS with respect to the center plane Poc, and are arranged on the same line as the irradiation center axes Le2, Le4, and Le6 on the XZ plane. That is, on the XZ plane, a line connecting the projection positions (reading positions) of the measuring beams projected from the encoders EC2a, EC2b on the scale portions SDa, SDb and the central axis AXo is arranged on the same line as the irradiation central axes Le2, Le4, Le 6.

The substrate FS is wound inside the scale portions SDa, SDb on both ends of the rotary drum DR. The outer peripheral surface of the scale unit SD (SDa, SDb) is set to be flush with the outer peripheral surface of the substrate FS wound around the rotary drum DR. That is, the radius (distance) from the scale portion SD (SDa, SDb) to the center axis AXo of the outer peripheral surface and the radius (distance) from the substrate FS wound around the rotary drum DR to the center axis AXo of the outer peripheral surface are set to be the same. Accordingly, the encoder EC (EC1a, EC1b, EC2a, EC2b) can detect the scale unit SD (SDa, SDb) at the same radial position as the irradiated surface of the substrate FS wound around the rotary drum DR, and reduce the abbe error caused by the difference between the measurement position and the processing position (such as the scanning position of the spot light SP) in the radial direction of the rotary drum DR.

However, since the thickness of the substrate FS as the irradiation object considerably varies from ten μm to several hundred μm, it is not easy to constantly make the radius of the outer peripheral surface of the scale portion SD (SDa, SDb) the same as the radius of the outer peripheral surface of the substrate FS wound around the rotary drum DR. Therefore, in the case of the scale portions SD (SDa, SDb) shown in fig. 2, the radius of the outer peripheral surface (scale surface) thereof is set to coincide with the radius of the outer peripheral surface of the rotary drum DR. Further, the scale section SD may be formed by a separate disk, and the disk (scale disk) may be coaxially attached to the shaft Sft of the rotary drum DR. At this time, the radius of the outer peripheral surface (scale surface) of the scale disk is preferably matched with the radius of the outer peripheral surface of the rotary drum DR so that the abbe error is controlled within an allowable value.

As shown in fig. 3, the alignment microscopes ALG (ALG1 to ALG4) shown in fig. 1 are provided in plural numbers (4 in the present embodiment) in the Y direction for detecting the alignment marks MK (MK1 to MK4) formed on the substrate FS. The alignment marks MK (MK1 to MK4) are reference marks for drawing a predetermined pattern of the exposure field W on the irradiated surface of the substrate FS and for aligning the substrate FS with respect to the position thereof. The alignment microscopes ALG (ALG1 to ALG4) detect alignment marks MK (MK1 to MK4) on the substrate FS supported by the circumferential surface of the rotating cylinder DR. The alignment microscopes ALG (ALG1 to ALG4) are provided on the upstream side (the (-X direction side) in the conveyance direction of the substrate FS with respect to the irradiation target region on the substrate FS than the spot light SP of the light beam LB (LB1 to LB6) from the exposure head 16.

The alignment microscopes ALG (ALG1 to ALG4) include a light source for projecting alignment illumination light onto the substrate FS, an observation optical system (including an objective lens) for obtaining an enlarged image of a local region including the alignment marks MK (MK1 to MK4) on the surface of the substrate FS, and an imaging element such as a CCD or a CMOS for taking an image with a high-speed shutter while the substrate FS is moving in the conveyance direction. Imaging signals captured by the alignment microscopes ALG (ALG1 to ALG4) are sent to the control device 18. The controller 18 detects the positions of the alignment marks MK (MK1 to MK4) based on the image analysis of the imaging signal and the information of the rotational position of the rotary drum DR at the moment of imaging (measured by the encoder EC which reads the scale portion SD shown in fig. 2), and detects the position of the substrate FS. The alignment illumination light is light in a wavelength band having little sensitivity to the photosensitive functional layer on the substrate FS, for example, light having a wavelength of about 500 to 800 nm.

Alignment marks MK 1-MK 4 are provided around each exposure field W. A plurality of alignment marks MK1, MK4 are formed at regular intervals Dh along the longitudinal direction of the substrate FS on both sides of the exposure field W in the width direction of the substrate FS. Alignment mark MK1 is formed on the-Y direction side in the width direction of substrate FS, and alignment mark MK4 is formed on the + Y direction side in the width direction of substrate FS. The alignment marks MK1 and MK4 are arranged at the same position in the longitudinal direction (X direction) of the substrate FS in a state where the substrate FS is subjected to a large tension and heat treatment without being deformed. Further, alignment marks MK2 and MK3 are formed between alignment mark MK1 and alignment mark MK4, and the margin portions on the + X direction side and the-X direction side of exposure field W are formed along the width direction (short side direction) of substrate FS. Alignment mark MK2 is formed on the-Y direction side in the width direction of substrate FS, and alignment mark MK3 is formed on the + Y direction side of substrate FS. The distance between alignment mark MK1 arranged at the-Y direction side end of substrate FS and alignment mark MK2 of the margin portion in the Y direction, the distance between alignment mark MK2 of the margin portion and alignment mark MK3 in the Y direction, and the distance between alignment mark MK4 arranged at the + Y direction side end of substrate FS and alignment mark MK3 of the margin portion in the Y direction are set to the same distance. These alignment marks MK (MK 1-MK 4) may be formed together during the formation of the pattern layer of layer 1. For example, when the pattern of the 1 st layer is exposed, the patterns for the alignment marks may be exposed together around the exposure area W of the pattern exposure. Also, alignment marks MK may be formed in exposure area W. For example, it may be formed within the exposure area W along the contour of the exposure area W.

The alignment microscope ALG1 is configured to photograph an alignment mark MK1 present in an observation region (detection region) Vw1 of the objective lens. Similarly, the alignment microscopes ALG2 to ALG4 are also arranged to capture alignment marks MK2 to MK4 existing in observation regions Vw2 to Vw4 of the objective lens. Therefore, the alignment microscopes ALG1 to ALG4 are provided in the order of the alignment microscopes ALG1 to ALG4 from the-Y direction side of the substrate FS corresponding to the positions of the alignment marks MK1 to MK 4. The alignment microscopes ALG (ALG1 to ALG4) are arranged in the X direction, and the distances between the exposure positions (the drawing lines SL1 to SL6) and the observation regions Vw (Vw1 to Vw4) of the alignment microscopes ALG are shorter than the length of the exposure region W in the X direction. The number of alignment microscopes ALG provided in the Y direction may be changed depending on the number of alignment marks MK formed in the width direction of the substrate FS. The size of the observation regions Vw1 to Vw4 on the irradiated surface of the substrate FS is set to the size of the reaction alignment marks MK1 to MK4 and the alignment accuracy (position measurement accuracy), but is about 100 to 500 μm square.

Fig. 4 is an enlarged view of a main part of the exposure apparatus EX. The exposure apparatus EX further includes a plurality of light introduction optical systems BDU (BDU1 to BDU6) and a main body frame UB. The light introduction optical system BDU (BDU1 to BDU6) guides the light beam LB (LB1 to LB6) from the light source device 14 to the light beam scanning device MD (MD1 to MD 6). The light introduction optical system BDU1 guides the light beam LB1 to the light beam scanning device MD1, and the light introduction optical system BDU2 guides the light beam LB2 to the light beam scanning device MD 2. Similarly, the light guide optical systems BDU3 to BDU6 guide the light beams LB3 to LB6 to the light beam scanning devices MD3 to MD 6. The light beam LB from the light source device 14 is transmitted through an optical member such as a beam splitter or a switching beam deflector, not shown, and is split or selectively incident into the respective optical waveguide systems BDU1 to BDU 6. The light-introducing optical system BDU (BDU1 to BDU6) includes drawing optical elements AOM (AOM1 to AOM6) that modulate (ON/OFF) the intensity of spot light SP projected onto the irradiated surface of the substrate FS by the beam scanning devices MD (MD1 to MD6) at high speed in accordance with pattern data. The drawing optical element AOM is an Acousto-Optic Modulator (Acousto-optical Modulator). This pattern data is stored in a memory area, not shown, of the control device 18.

And a body frame UB for holding the plurality of light guide optical systems BDU 1-BDU 6 and the plurality of light beam scanning devices MD 1-MD 6. The main body frame UB includes a 1 st frame part UB1 for holding the plurality of light guide optical systems BDU1 to BDU6, and a 2 nd frame part UB2 for holding the plurality of light beam scanning devices MD1 to MD 6. The 1 st frame part Ub1 holds a plurality of light guide optical systems BDU1 to BDU6 above (+ Z direction side) the plurality of light beam scanning devices MD1 to MD6 held by the 2 nd frame part Ub 2. The odd-numbered light guiding optical systems BDU1, BDU3, and BDU5 are held by the 1 st frame part Ub1 so as to be disposed on the upstream side (on the side in the X direction) of the substrate FS in the conveyance direction with respect to the center plane Poc in accordance with the positions of the odd-numbered light beam scanning devices MD1, MD3, and MD 5. The even-numbered light guide optical systems BDU2, BDU4, and BDU6 are held by the 1 st frame part Ub1 so as to be arranged on the downstream side in the conveyance direction of the substrate FS (+ X direction side) with respect to the center plane Poc in accordance with the positions of the even-numbered beam scanning devices MD2, MD4, and MD 6. The configuration of the light introducing optical system BDU will be described in detail later.

Frame part 1 Ub1 supports a plurality of light guide optical systems BDU1 to BDU6 from below (the side in the Z direction). In the 1 st frame part Ub1, a plurality of openings Hs (Hs1 to Hs6) are provided corresponding to the plurality of light introduction optical systems BDU1 to BDU 6. With the openings Hs1 to Hs6, the light beams LB1 to LB6 emitted from the light introduction optical systems BDU1 to BDU6 enter the corresponding light beam scanning devices MD1 to MD6 without being blocked by the 1 st frame part Ub 1. That is, the light beams LB (LB1 to LB6) emitted from the light guide optical system BDU (BDU1 to BDU6) enter the beam scanning device MD (MD1 to MD6) through the openings Hs (Hs1 to Hs 6).

The 2 nd frame part Ub2 holds the beam scanning devices MD (MD1 to MD6) rotatably about the irradiation center axis Le (Le1 to Le 6). That is, the 2 nd frame part Ub2 allows the beam scanning devices MD (MD1 to MD6) to rotate about the irradiation center axis Le (Le1 to Le 6). The structure for holding the beam scanning device MD by the 2 nd frame unit Ub2 will be described in detail later.

Fig. 5 is a detailed view showing the optical configuration of the light introducing optical system BDU, and fig. 6 is a schematic explanatory view for describing optical path switching (ON/OFF of the light beam LB) by the optical element AOM. The odd-numbered light guide optical systems BDU1, BDU3, and BDU5 and the even-numbered light guide optical systems BDU2, BDU4, and BDU6 are arranged symmetrically with respect to the central plane Poc. Since the light introduction optical systems BDU (BDU1 to BDU6) have the same configuration, only the light introduction optical system BDU1 will be described, and the description of the other light introduction optical systems BDU will be omitted.

The light-guiding optical system BDU1 includes optical lens systems G1 and G2 and mirrors M1 to M5 in addition to the drawing optical element AOM 1. For the drawing optical element AOM1, the light beam LB1 enters in a waist-shaped manner within the drawing optical element AOM 1. As shown in fig. 6, the drawing optical element AOM1 allows the incident light beam LB1 to pass through the absorber AB when the drive signal (high frequency signal) from the control device 18 is off (low), and allows 1 st diffracted light beam diffracted from the incident light beam LB1 to be directed to the mirror M1 when the drive signal (high frequency signal) from the control device 18 is on (high). The absorber AB is a light trap that absorbs the beam LB1 to prevent the beam LB1 from leaking to the outside. The controller 18 turns ON/OFF (High/Low) the drive signal (High frequency signal) to be applied to the drawing optical element AOM1 at High speed based ON the pattern data, and switches the light beam LB1 to the mirror M1 (the drawing optical element AOM1 is ON) or to the absorber AB (the drawing optical element AOM1 is OFF). Thus, when viewed on the surface to be irradiated of the substrate FS, the intensity of the spot light SP of the beam LB1 reaching the surface to be irradiated (the substrate FS) from the beam scanning device MD1 is adjusted to either a high level or a low level (for example, zero level) at high speed in accordance with the pattern data.

The pattern data is bitmap data composed of a plurality of pixel data divided into two dimensions, in which a direction along the scanning direction (Y direction) of the spot light SP is a row direction and a direction along the conveying direction (X direction) of the substrate FS is a column direction. The pixel data is 1-bit data of "" 0 "" or "" 1 "". The pixel data of "0" represents that the intensity of the spot light SP irradiated on the substrate FS is set to a low level, and the pixel data of "1" represents that the intensity of the spot light SP irradiated on the substrate FS is set to a high level. Therefore, the control device 18 outputs the OFF drive signal (high frequency signal) to the drawing optical element AOM1 of the optical waveguide system BDU1 when the pixel data is "0", and outputs the ON drive signal (high frequency signal) to the drawing optical element AOM1 when the pixel data is "1". The number of pixel data of 1 column of the pattern data is determined in response to the pixel size on the irradiated surface and the length of the drawing line SLn, and the size of 1 pixel is determined by the size of the spot light SP

And (6) determining. As described above, the spot light SP continuously irradiated on the irradiated surface is only sized

1/2, the size of 1 pixel is set to the size of the spot light SP

To an extent of, or higher than, this. For example, the effective size of the spot light SP

In the case of 3 μm (the amount of overlap is 1.5 μm), the size of 1 pixel is set to be about 3 μm square or higher. Therefore, in order to draw a finer pattern, the effective size of the spot light SP needs to be set

Set smaller to set the size of 1 pixel smaller. Therefore, the spot light SP is overlapped only by the size

At level 1/2, the number of spot lights SP projected along the drawing line SL1 (the number of pulses) is 2 times the number of 1-column pixel data of the pattern data. This pattern data is stored in a memory not shown. Further, the 1-column pixel data may be referred to as a pixel data column Dw, and the pattern data is bitmap data in which a plurality of pixel data columns Dw (Dw1, Dw2,. cndot., Dwn) are arranged in the column direction.

Specifically, the control device 18 reads out the pixel data line (pixel data of 1 column) Dw (e.g., Dw1) of the pattern data, and sequentially outputs the drive signal according to the read out pixel data of the pixel data line Dw1 to the drawing optical element AOM1 of the optical waveguide optical system BDU1 in synchronization with the scanning of the spot light SP by the beam scanning device MD 1. Specifically, the data of 1 pixel selected in the read pixel data column Dw1 is shifted in the row direction at a timing of 2 pulses per dot light SP projected along the drawing line SL1, and a driving signal according to the selected data of 1 pixel is sequentially output to the drawing optical element AOM 1. Accordingly, the intensity of the spot light SP irradiated on the irradiation surface of the substrate FS is modulated according to the pixel data for every 2 pulses. When the scanning of the spot light SP is completed, the control device 18 reads out the pixel data line Dw2 of the next line. When the scanning of the spot light SP by the beam scanning device MD1 is started, the driving signal based on the pixel data of the read pixel data line Dw2 is output to the drawing optical element AOM1 of the optical waveguide system BDU 1. In this way, each time the scanning of the spot light SP is started, the driving signal according to the pixel data of the pixel data line Dw of the next line is output to the drawing optical element AOM 1. Thus, the pattern according to the pattern data can be drawn and exposed. Further, pattern data is set for each beam scanning device MD.

The light beam LB1 from the drawing optical element AOM1 is transmitted through the optical lens system for beam shaping G1 and enters the absorber AB or the mirror M1. That is, the light beam LB1 passing through the drawing optical element AOM1 passes through the optical lens system G1 even when the drawing optical element AOM1 is ON or OFF. When the drawing optical element AOM1 is switched ON and the light beam LB1 enters the mirror M1, the light beam LB1 is bent in the optical path by the mirrors M1 to M5 in fig. 5 and then emitted from the mirror M5 to the beam scanning device MD 1. At this time, the mirror M5 emits the beam LB1 coaxially with the irradiation center axis Le 1. That is, the light beam LB1 from the light introduction optical system BDU1 is bent such that the optical path is reflected by the mirrors M1 to M5 of the light introduction optical system BDU1 so that the light beam LB1 enters the beam scanning apparatus MD1 with the axis thereof being coaxial with the irradiation center axis Le1 set in the beam scanning apparatus MD 1. An optical lens system G2 for beam shaping is provided between the mirror M4 and the mirror M5. The exposure head 16, which is constituted by at least a plurality of beam scanning devices MD (MD1 to MD6), and the light introduction optical systems BDU (BDU1 to BDU6) constitute the drawing device of the present embodiment. The main body frame UB may be a part of the drawing device.

Next, the optical configuration of the optical beam scanning device MD will be described with reference to fig. 7 (and fig. 5). Since the respective beam scanning apparatuses MD (MD1 to MD6) have the same configuration, only the beam scanning apparatus MD1 will be described, and the description of the other beam scanning apparatuses MD will be omitted. In fig. 7 (and fig. 5), the direction parallel to the irradiation center axis Le (Le1) is the Zt direction, the direction of the substrate FS from the processing apparatus PR1 to the processing apparatus PR2 through the exposure apparatus EX on the plane orthogonal to the Zt direction is the Xt direction, and the direction orthogonal to the Xt direction on the plane orthogonal to the Zt direction is the Yt direction. That is, the three-dimensional coordinates Xt, Yt, and Zt in fig. 7 (and fig. 5) are three-dimensional coordinates obtained by rotating the three-dimensional coordinate X, Y, Z in fig. 1 around the Y axis so that the Z axis direction is parallel to the irradiation center axis Le (Le 1).

As shown in fig. 7, in the beam scanning apparatus MD1, along the traveling direction of the beam LB1 from the incident position of the beam LB1 to the surface to BE irradiated (substrate FS), a mirror M10, a beam expander BE, a mirror M11, a polarizing beam splitter BS1, a mirror M12, an image shift optical member (parallel plate) SR, a deflection adjusting optical member (prism) DP, a field aperture FA, a mirror M13, a λ/4 wavelength plate QW, a cylindrical lens CYa, a mirror M14, a polygon mirror (polygon mirror) PM, an f θ lens FT, a mirror M15, and a cylindrical lens CYb are provided. Further, the beam scanning apparatus MD1 is provided with an optical lens system G10 and a photodetector DT1 for detecting reflected light from the irradiated surface (substrate FS) by passing through the polarization beam splitter BS 1.

The light beam LB1 incident on the light beam scanning device MD1 travels in the-Zt direction and enters the mirror M10 inclined at 45 ° to the XtYt plane. The axis of the beam LB1 incident on the beam scanning device MD1 is incident on the mirror M10 coaxially with the irradiation center axis Le 1. The mirror M10 functions as an incident optical member for causing the light beam LB1 to enter the light beam scanning apparatus MD1, and reflects the incident light beam LB1 toward the mirror M11 along the optical axis AXa set parallel to the Xt axis in the-Xt direction. Therefore, the optical axis AXa is orthogonal to the irradiation center axis Le1 in a plane parallel to the XtZt plane. The light beam LB1 reflected by the mirror M10 passes through a beam expander BE disposed along the optical axis AXa and is incident on the mirror M11. A beam expander BE to enlarge the diameter of the penetrating light beam LB 1. The beam expander BE includes a condenser lens BE1 and a collimator lens BE2 for collimating the light beam LB1 condensed by the condenser lens BE1 and emitted.

The mirror M11 is disposed inclined at 45 ° to the YtZt plane, and reflects the incident light beam LB1 (optical axis AXa) in the-Yt direction toward the polarization beam splitter BS 1. The polarization separation surface of the polarization beam splitter BS1 is disposed to be inclined at 45 ° to the YtZt plane, and reflects a P-polarized light beam and transmits a linearly polarized light beam (S-polarized light) polarized in a direction orthogonal to the P-polarized light beam. Since the light beam LB1 incident on the light beam scanning device MD1 is a P-polarized light beam, the polarization beam splitter BS1 reflects the light beam LB1 from the mirror M11 in the-Xt direction and guides the light beam to the mirror M12 side.

The mirror M12 is disposed inclined at 45 ° to the XtYt plane, and reflects the incident light beam LB1 in the-Zt direction toward the mirror M13 separated from the mirror M12 in the-Zt direction. The beam LB1 reflected by the mirror M12 passes through the image shift optical member SR, the shift adjustment optical member DP, and the field aperture (field stop) FA along the optical axis AXc parallel to the Zt axis, and enters the mirror M13. The image shift optical member SR performs two-dimensional adjustment of the center position of the light beam LB1 in the cross section thereof in a plane (XtYt plane) orthogonal to the traveling direction (optical axis AXc) of the light beam LB 1. The image shift optical member SR is constituted by parallel flat plates SR1, SR2 of 2 pieces of quartz arranged along the optical axis AXc, the parallel flat plate SR1 is tiltable around the Xt axis, and the parallel flat plate SR2 is tiltable around the Yt axis. The parallel flat plates Sr1 and Sr2 are inclined around the Xt axis and the Yt axis, respectively, and the center position of the beam LB1 is slightly shifted in two dimensions on the XtYt plane orthogonal to the traveling direction of the beam LB 1. The parallel flat plates Sr1, Sr2 are driven by actuators (driving units), not shown, under the control of the controller 18.

The deflection adjusting optical member DP finely adjusts the inclination of the light beam LB1 reflected by the mirror M12 and passing through the image deflecting optical member SR with respect to the optical axis AXc. The deflection adjusting optical member DP is configured by 2 wedge-shaped prisms DP1 and DP2 arranged along the optical axis AXc, and the prisms DP1 and DP2 are provided to be independently rotatable by 360 ° about the optical axis AXc. By adjusting the rotational angle positions of the 2 prisms Dp1, Dp2, the axis of the beam LB1 reaching the mirror M12 is made parallel to the optical axis AXc, or the axis of the beam LB1 reaching the surface to be irradiated (substrate FS) is made parallel to the irradiation central axis Le 1. Further, the beam LB1 deflected and adjusted by the 2 prisms Dp1 and Dp2 may traverse in a plane parallel to the cross section of the beam LB, and this traverse may be returned to the original state by the previous image shift optical member SR. The prisms Dp1 and Dp2 are driven by an actuator (driving unit), not shown, under the control of the control device 18.

As described above, the light beam LB1 passing through the image shift optical member SR and the deflection adjusting optical member DP passes through the circular opening of the field aperture (field aperture) FA to reach the mirror M13. The circular opening of the field aperture FA is a diaphragm for removing a gentle portion of the intensity distribution in the cross section of the light beam LB1 amplified by the beam expander BE. When the circular opening of the field aperture FA is replaced with a variable color diaphragm whose aperture can be adjusted, the intensity (luminance) of the spot light SP can be adjusted.

The mirror M13 is disposed inclined at 45 ° to the XtYt plane, and reflects the incident light beam LB1 toward the mirror M14 in the + Xt direction. The beam LB1 reflected by the mirror M13 passes through the λ/4 wavelength plate QW and the cylindrical lens CYa and enters the mirror M14. The mirror M14 reflects the incident light beam LB1 toward a polygon mirror (rotary polygon mirror, scanning deflecting member) PM. The polygon mirror PM reflects the incident light beam LB1 toward the + Xt direction side toward an f θ lens FT having an optical axis AXf parallel to the Xt axis. The polygon mirror PM deflects (reflects) the incident beam LB1 in a plane parallel to the XtYt plane in order to scan the spot light SP of the beam LB1 on the irradiated surface of the substrate FS. Specifically, the polygon mirror PM has a rotation axis AXp extending in the Zt-axis direction, and a plurality of reflection surfaces RP (8 reflection surfaces RP in the present embodiment) formed around the rotation axis AXp. By rotating the polygon mirror PM in a predetermined rotational direction about the rotational axis AXp, the reflection angle of the pulsed light beam LB1 irradiated on the reflection surface RP can be continuously changed. Accordingly, the reflection direction of the beam LB1 is deflected by 1 reflection surface RP, and the spot light SP of the beam LB1 irradiated on the irradiated surface of the substrate FS can be scanned in the scanning direction (the width direction of the substrate FS, the Yt direction).

That is, the spot light SP of the light beam LB1 can be scanned along the drawing line SL1 by 1 reflection surface RP. Therefore, the number of the scanning lines SL1 on the irradiated surface of the substrate FS scanned by the spot light SP is 8, which is the same as the number of the reflection surfaces RP, by 1 rotation of the polygon mirror PM. The polygon mirror PM is rotated at a constant speed by a polygon mirror driving section RM including a motor and the like. The rotation of the polygon mirror PM by the polygon mirror driving section RM is controlled by the control device 18. As described above, the effective length (for example, 50mm) of the drawing line SL1 is set to a length equal to or less than the maximum scanning length (for example, 51mm) of the spot light SP that can be scanned by the polygon mirror PM, and the center point of the drawing line SL1 (through which the irradiation center axis Le1 passes) is set at the center of the maximum scanning length in the initial setting (in design).

For example, the effective length of the drawing line SL1 is set to 50mm, and the effective size is set to

When the 4 μm spot light SP is irradiated onto the irradiated surface of the substrate FS along the drawing line SL1 while being overlapped at every 2.0 μm, the number of spot lights SP (pulsed light) irradiated in one scan is 25000(═ 50mm/2.0 μm). When the traveling speed (conveyance speed) Vt of the substrate FS in the sub-scanning direction is 8 mm/sec and the scanning of the spot light SP in the sub-scanning direction is performed at intervals of 2.0 μm, the time difference Tpx between the scanning start time of one scan along the drawing line SL1 and the scanning start time of the next scan is 250 μ sec (2.0 μm/(8 mm/sec)). This time difference Tpx is a time when the polygon mirror PM of the 8 reflection surface RP rotates by an angle of 45 ° (═ 360 °/8) for 1 facet. At this time, since the time of 1 rotation of the polygon mirror PM is set to 2.0 msec (8 × 250 μ sec), the rotation speed Vp of the polygon mirror PM is set to 3 ten thousand rpm, which is 1/2.0 msec per 500 seconds of rotation.

On the other hand, the maximum angle of incidence (corresponding to the maximum scan length of the spot light SP) at which the light beam LB1 reflected on the 1-reflection surface RP of the polygon mirror PM effectively enters the f θ lens FT is approximately determined by the focal length of the f θ lens FT and the maximum scan length. For example, in the case of the polygon mirror PM having 8 reflection surfaces RP, the ratio of the rotation angle contributing to the real scanning (scanning efficiency α p) of the rotation angle of 45 ° of 1 reflection surface RP is about 1/3 degrees, corresponding to the maximum incident angle of view of the f θ lens FT (± 15 ° range, that is, 30 ° range). Therefore, the effective time Tss of the 1 sweep of the spot light SP along the drawing line SL1 is Tss ≈ Tpx/3, and the time Tss is 83.33 · μ sec in the case of the previous numerical example. Therefore, it is necessary to irradiate a spot light SP (pulsed light) of 25000 during this time Tss, and therefore the emission frequency Fe of the pulsed light beam LB from the light source device 14 is 25000 times/83.333 · μ sec, 300 MHz.

In accordance with the above, the size of the spot light SP

(μm), the emission frequency Fe (Hz) of the light source device 14, the length of the drawing line SLn is LBL (μm), the overlapping rate of the spot light SP is UO (0 < UO < 1), the conveying speed of the substrate FS is Vt (μm/sec), the number of the reflection surfaces RP of the polygon mirror PM is Np, the scanning efficiency of each reflection surface RP of the polygon mirror PM is α p (0 < α p < 1), and

in this case, the rotation speed Vp (rps) of the polygon mirror PM is represented by Vp ═ Vt/(Np · YP), and the emission frequency Fe (hz) is represented by Fe ═ LBL · Vt/(α p · YP)²) And (4) showing. When these 2 relational expressions are integrated at the transport speed Vt, the following expression is obtained.

Vt＝(Vp·Np·YP)＝(Fe·αp·YP²/LBL)

Therefore, the transport speed Vt (μm/sec) of the substrate FS, the rotation speed vp (rps) of the polygon mirror PM, and the light emission frequency fe (hz) of the light source device 14 are adjusted so as to satisfy this relationship.

Returning to the explanation of fig. 7 again, the cylindrical lens CYa converges the incident light beam LB1 in a slit shape on the reflection surface RP of the polygon mirror PM in a non-scanning direction (Zt direction) orthogonal to the scanning direction (rotation direction) of the polygon mirror PM. Even if the reflection surface RP is inclined with respect to the Zt direction (inclination of the reflection surface RP with respect to the normal line of the XtYt plane) by the cylindrical lens CYa having the generatrix parallel to the Yt direction, the irradiation position of the beam LB1 irradiated on the irradiated surface of the substrate FS can be suppressed from deviating from the Xt direction while suppressing the influence thereof.

The f θ lens FT having the optical axis AXf extending in the Xt-axis direction is a telecentric system scanning lens that projects the light beam LB1 reflected by the polygon mirror PM onto the mirror M15 so as to be parallel to the optical axis AXf on the XtYt plane. The incident angle θ of the light beam LB1 to the f θ lens FT varies according to the rotation angle (θ/2) of the polygon mirror PM. The f θ lens FT projects the beam LB1 at an image height position on the irradiated surface of the substrate FS proportional to the incident angle θ through the mirror M15 and the cylindrical lens CYb. When the focal length is fo and the image height position is y, the f θ lens FT is designed to satisfy the relationship of y being fo · θ. Therefore, the f θ lens FT can accurately scan the light beam LB1 at a constant speed in the Yt direction (Y direction). When the incident angle θ upon the f θ lens FT is 0 degrees, the light beam LB1 incident upon the f θ lens FT travels along the optical axis AXf.

The mirror M15 reflects the incident beam LB1 in the-Zt direction toward the substrate FS through the cylindrical lens CYb. The light beam LB1 projected onto the substrate FS is converged into a minute spot light SP having a diameter of about several μm (for example, 3 μm) on the surface to be irradiated of the substrate FS by the f θ lens FT and the cylindrical lens CYb having a bus line parallel to the Yt direction. The spot light SP projected onto the irradiated surface of the substrate FS is one-dimensionally scanned by the polygon mirror PM with a drawing line SL1 extending in the Yt direction. The optical axis AXf of the f θ lens FT is on the same plane as the irradiation center axis Le1, and the plane is parallel to the XtZt plane. Therefore, the light beam LB1 traveling on the optical axis AXf is reflected in the-Zt direction by the mirror M15, and is projected on the substrate FS coaxially with the irradiation center axis Le 1. In the present embodiment, at least the f θ lens FT functions as a projection optical system that projects the light beam LB1 deflected by the polygon mirror PM onto the surface to be irradiated of the substrate FS. At least the reflecting members (the mirrors M11 to M15) and the polarization beam splitter BS1 function as an optical path deflecting member for bending the optical path of the light beam LB1 from the mirror M10 to the substrate FS. The optical path deflecting member can make the incident axis of the beam LB1 incident on the mirror M10 substantially coaxial with the irradiation center axis Le 1. In the XtZt plane, the light beam LB1 passing through the beam scanning device MD1 passes through a substantially U-shaped or C-shaped optical path, and then advances in the-Zt direction to be projected onto the substrate FS.

As described above, in a state where the substrate FS is conveyed in the X direction, the spot light SP of the beam LB (LB1 to LB6) is one-dimensionally scanned in the scanning direction (Y direction) by the beam scanning devices MD (MD1 to MD6), and thus the irradiated surface of the substrate FS is relatively two-dimensionally scanned by the spot light SP. Therefore, a predetermined pattern can be drawn and exposed in the exposure area W of the substrate FS. The drawing optical elements AOMs (AOM1 to AOM6) are provided in the light introduction optical system BDU (BDU1 to BDU6), but may be provided in the beam scanning device MD. In this case, it is preferable to provide the drawing optical element AOM between the mirror M10 and the mirror M14.

The photodetector DT1 has a photoelectric conversion element that photoelectrically converts incident light. A predetermined reference pattern is formed on the surface of the rotary drum DR. The portion of the rotary drum DR on which the reference pattern is formed is made of a material having a low reflectance (10 to 50%) with respect to the wavelength band of the light beam LB, and the other portion of the rotary drum DR on which the reference pattern is not formed is made of a material having a reflectance of 10% or less or a material that absorbs light. Therefore, when the spot light SP of the beam LB1 from the beam scanning device MD1 is irradiated on the region of the rotating cylinder DR where the reference pattern is formed in a state where the substrate FS is unwound (or in a state where the transparent portion of the substrate FS passes), the reflected light thereof passes through the cylindrical lens CYb, the mirror M15, the f θ lens FT, the polygon mirror PM, the mirror M14, the cylindrical lens CYa, the λ/4 wavelength plate QW, the mirror M13, the field aperture FA, the deflection adjusting optical member DP, the image shifting optical member SR, and the mirror M12 and enters the polarization beam splitter BS 1. Here, a λ/4 wavelength plate QW is provided between the polarization beam splitter BS1 and the substrate FS, specifically, between the mirror M13 and the cylindrical lens CYa. Thus, the beam LB1 irradiated on the substrate FS, i.e., the beam LB1 converted from P-polarized light to circularly polarized light by the λ/4 wavelength plate QW, is converted from circularly polarized light to S-polarized light by the λ/4 wavelength plate QW, and the reflected light entering the polarizing beam splitter BS1 from the substrate FS. Therefore, the reflected light from the substrate FS passes through the polarization beam splitter BS1, passes through the optical lens system G10, and enters the photodetector DT 1.

At this time, in a state where the drawing optical element AOM1 of the light guide optical system BDU1 is turned ON, that is, in a state where the pulsed light beam LB1 is continuously incident ON the beam scanning device MD1, the spot light SP is scanned by the beam scanning device MD1 by rotating the rotary drum DR, and the spot light SP is two-dimensionally irradiated ON the outer peripheral surface of the rotary drum DR. Therefore, the image of the reference pattern formed on the rotary drum DR can be acquired by the photodetector DT 1.

Specifically, the intensity of the photoelectric signal output from the photodetector DT1 is changed, and a clock pulse signal (generated in the light source device 14) for performing pulse light emission of the spot light SP is applied, and digital sampling is performed for each scanning time, and the data is obtained as one-dimensional image data in the Yt direction. Further, in response to the measurement value of the encoder EC which measures the rotational angle position of the rotary drum DR, a certain distance (for example, the size of the spot light SP) in the sub-scanning direction

1/2) arranging the one-dimensional image data in the Yt direction in the Xt direction to obtain two-dimensional image information on the surface of the rotary drum DR. The control device 18 measures the inclination of the drawing line SL1 of the optical beam scanning device MD based on the obtained two-dimensional image information of the reference pattern of the rotary drum DR. The inclination of the drawing line SL1 may be relative inclination between the respective beam scanning apparatuses MD (MD1 to MD6) or inclination (absolute inclination) with respect to the central axis AXo of the rotary drum DR. Of course, the inclination of each of the drawing lines SL2 to SL6 may be measured in the same manner.

As shown in fig. 8, an origin sensor 20 is provided around the polygon mirror PM of the beam scanning device MD 1. The origin sensor 20 outputs a pulse-like origin signal SH indicating the start of scanning of the spot light SP by each reflection surface RP. The origin sensor 20 outputs an origin signal SH when the rotational position of the polygon mirror PM reaches a predetermined position before the scanning of the spot light SP by the reflection surface RP is started. The polygon mirror PM deflects the beam LB1 projected onto the substrate FS within the effective scanning angle range θ s. That is, when the reflection direction (deflection direction) of the light beam LB1 reflected by the polygon mirror PM falls within the effective scanning angle range θ s, the reflected light beam LB1 enters the f θ lens FT. Therefore, the origin sensor 20 outputs the origin signal SH when the rotational position of the polygon mirror PM reaches a predetermined position before the reflection direction of the light beam LB1 reflected by the reflection surface RP enters within the effective scanning angle range θ s. Since the scanning of the spot light SP is performed 8 times during the 1 rotation of the polygon mirror PM, the origin sensor 20 also outputs the origin signal SH 8 times during the 1 rotation. The origin signal SH detected by the origin sensor 20 is sent to the control device 18. When the origin sensor 20 outputs the origin signal SH, the scanning of the spot light SP along the drawing line SL1 is started.

The origin sensor 20 outputs an origin signal SH using a reflection surface RP adjacent to the reflection surface RP (in the present embodiment, the previous reflection surface RP in the rotation direction of the polygon mirror PM) on which the scanning of the spot light SP (the deflection of the beam LB) is to be started. In order to distinguish the reflection surfaces RP from each other, in fig. 8, the reflection surface RP on which the light beam LB1 is deflected is denoted by RPa, and the other reflection surfaces RP are denoted by RPb to RPh in the counterclockwise direction (the direction opposite to the rotation direction of the polygon mirror PM).

The origin sensor 20 includes a beam transmission system 20a, and the beam transmission system 20a includes a light source section 22 that emits a laser beam Bga in a wavelength band that is not photosensitive, such as a semiconductor laser beam, and mirrors 24 and 26 that reflect the laser beam Bga from the light source section 22 and project the reflected laser beam onto the reflection surface RPb of the polygon mirror PM. The origin sensor 20 includes a beam receiving system 20b, and the beam receiving system 20b includes a light receiving portion 28, mirrors 30 and 32 that guide the reflected light (reflected light beam Bgb) of the laser beam Bga reflected on the reflection surface RPb to the light receiving portion 28, and a lens system 34 that condenses the reflected light beam Bgb reflected by the mirror 32 into a minute spot light. The light receiving unit 28 has a photoelectric conversion element that receives the spot light of the reflected light beam Bgb condensed by the lens system 34. Here, the position where the laser beam Bga is projected on each reflection surface RP of the polygon mirror PM is set to be a pupil plane (focal position) of the lens system 34.

The beam transmitting system 20a and the beam receiving system 20b are provided at positions capable of receiving the reflected beam Bgb of the laser beam Bga emitted from the beam transmitting system 20a when the rotational position of the polygon mirror PM reaches a predetermined position immediately before the start of scanning of the spot light SP with the reflection surface RP. That is, the beam transmitting system 20a and the beam receiving system 20b are provided at positions where they can receive the reflected beam Bgb of the laser beam Bga emitted from the beam transmitting system 20a when the reflection surface RP that scans the spot light SP reaches a predetermined angular position. In fig. 8, reference symbol Msf denotes a shaft of a rotary motor of the polygon mirror driving unit RM disposed coaxially with the rotary shaft AXp.

A light-shielding member (not shown) having a minute slit opening is provided in the light-receiving section 28 in front of the light-receiving surface of the photoelectric conversion element. While the angular position of the reflection surface RPb is within the predetermined angular range, the reflected light beam Bgb enters the lens system 34, and the spot light of the reflected light beam Bgb scans in a predetermined direction on the light-shielding body in the light-receiving unit 28. In this scanning, the spot light of the reflected light beam Bgb passing through the slit opening of the light-shielding body is received by the photoelectric conversion element, and the received light signal is amplified by the amplifier and output as a pulse-shaped origin signal SH.

As described above, the origin sensor 20 detects the origin signal SH using the reflection surface RPb immediately before the rotation direction by the reflection surface RPa deflecting the light beam LB (scanning spot light SP). Therefore, when the angles η j between the adjacent reflection surfaces RP (for example, the reflection surfaces RPa and RPb) have an error with respect to the design value (135 degrees when the reflection surfaces RP are 8), the timing of generating the origin signal SH may be different for each reflection surface RP due to the distribution of the error, as shown in fig. 9.

In fig. 9, an origin signal SH generated by using the reflection surface RPb is SH 1. Similarly, the origin signal SH generated using the reflection surfaces RPc, RPd, RPe, · · · · is SH2, SH3, SH4, · · · · · · · · · · · · · · · · · s. When an angle η j between adjacent reflection surfaces RP of the polygon mirror PM is a design value, an interval of generation timings of the origin signals SH (SH1, SH2, SH3, · ·) is a time Tpx. This time Tpx is a time required for the polygon mirror PM to rotate one side of the reflecting surface RP. However, in fig. 9, due to an error in the angle η j between the reflection surfaces RP of the polygon mirror PM, the timing of the origin signal SH generated using the reflection surfaces RPc and RPd deviates from the normal generation timing. Further, the time intervals Tp1, Tp2, Tp3, · · s · for generating the origin signals SH1, SH2, SH3, SH4, · · s · are not constant on the μ second scale due to manufacturing errors of the polygon mirror PM. In the timing chart shown in FIG. 9, Tp1 < Tpx, Tp2 > Tpx, and Tp3 < Tpx are shown. When the number of the reflection surfaces RP is Np and the rotational speed of the polygon mirror PM is Vp, the time Tpx becomes 1/(Np × Vp). For example, when the rotation speed Vp is 3 ten thousand rpm (500 RPs) and the number Np of the reflection surfaces RP of the polygon mirror PM is 8, the time Tpx is 250 μ sec. In fig. 9, for the sake of easy understanding of the description, the timing deviation of the origin signals SH1, SH2, SH3, · is exaggerated.

Therefore, the position of the drawing start point (scanning start point) of the spot light SP drawn by the respective reflection surfaces RP (RPa to RPh) on the irradiated surface of the substrate FS in the main scanning direction is deviated by the error of the angles η j between the adjacent reflection surfaces RP of the polygon mirror PM. As a result, the position of the drawing end point also deviates in the main scanning direction. That is, the positions of the drawing start point and the drawing end point of the dot light SP drawn by each reflection surface RP are not aligned in the X direction. The reason why the positions of the drawing start point and the drawing end point of the spot light SP are deviated in the main scanning direction is that Tp1, Tp2, Tp3, · · · · · · Tpx is not caused.

Therefore, in the present embodiment, as shown in the timing chart of fig. 9, the drawing of the spot light SP is started with the lapse of time Tpx after the generation of one pulse-shaped origin signal SH as the drawing start point. That is, after the origin signal SH is generated for the time Tpx, the control device 18 sequentially outputs the drive signals (ON/OFF) in response to the pixel data of the pixel data row Dw to the drawing optical element AOM1 of the optical waveguide optical system BDU1 through which the light beam LB1 is incident from the light beam scanning device MD 1. In this way, the reflection surface RPb for detecting the origin signal SH and the reflection surface RP of the actual scanning spot light SP can be the same reflection surface.

Specifically, the controller 18 outputs the drive signals in response to the pixel data of the pixel data line Dw1 in sequence to the drawing optical element AOM1 of the light guide optical system BDU1 after the elapse of time Tpx after generating the origin signal SH 1. In this way, the spot light SP can be scanned by the reflection surface RPb for detecting the origin signal SH 1. Next, the controller 18 generates the elapsed time Tpx in the home signal SH2, and then sequentially outputs the driving signals in response to the pixel data of the pixel data line Dw2 to the drawing optical element AOM1 of the light guide optical system BDU 1. In this way, the spot light SP can be scanned by the reflection surface RPc for detecting the origin signal SH 2. As described above, by scanning the spot light SP using the reflection surfaces RP for detecting the origin signal SH, even when there is an error in each angle η j between adjacent reflection surfaces RP of the polygon mirror PM, it is possible to suppress the deviation in the main scanning direction of the positions of the drawing start point and the drawing end point of the spot light SP drawn by each of the reflection surfaces RP (RPa to RPh) on the surface to be irradiated of the substrate FS.

To achieve the above object, the time Tpx for which the polygon mirror PM rotates by 45 degrees must be accurate to the μ second level, that is, the polygon mirror PM must be rotated at a constant speed accurately without deviation in speed. When the polygon mirror PM is rotated at a constant speed accurately, the reflection surface RP for generating the origin signal SH is rotated 45 degrees exactly after the time Tpx, and the light beam LB1 is reflected toward the f θ lens FT. Therefore, by increasing the constant rotation speed of the polygon mirror PM and also reducing the speed unevenness during one rotation as much as possible, the position of the reflection surface RP for generating the origin signal SH and the position of the reflection surface RP for deflecting the light beam LB1 to scan the spot light SP can be made different. Thus, the degree of freedom in the arrangement of the origin sensor 20 can be increased, and the origin sensor having a high rigidity and a stable structure can be installed. The reflection surface RP to be detected by the origin sensor 20 is set to be one before the rotation direction of the reflection surface RP that deflects the light beam LB1, but is not limited to the one before the rotation direction of the polygon mirror PM. In this case, when the reflection surface RP to be detected by the origin sensor 20 is n (an integer equal to or greater than 1) times before the rotation direction of the reflection surface RP in which the light beam LB1 is deflected, the drawing start point may be set after the generation of the origin signal SH has elapsed n × time Tpx.

Further, when the drawing start point is set to n × time Tpx for each of the origin signals SH1, SH2, SH3, ·, and · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · correction calculation, processing time corresponding to the pixel data line of each drawing line SL1 can be sufficient. Therefore, it is able to surely prevent the transmission error of pixel data line, the error of pixel data line and the local disappearance.

Further, assuming that the number Np of the reflection surface RP of the polygon mirror PM is 8, the rotation number (rotation speed) Vp is 3.6 ten thousand rpm, the scanning efficiency α p ≦ 1/3, and the effective diameter of the spot light SP on the substrate FS

3 μm, a length LBL of the drawing line SL1 of 50mm, and a pitch YP of the drawing line SL1 in the sub-scanning direction (Xt direction) from the diameter of the spot light SP

Is set as (0 < UO < 1)

Then, the one-scan time Tss of the spot light SP on the drawing line SL1 is Tss ═ α p × Tpx ═ α p × 1/(Np × Vp) ═ 1/1.44(m seconds). The scanning speed Vss of the spot light SP on the drawing line SL1 is Vss LBL/Tss 720 (m/sec). When the overlapping ratio Uo is 1/2, that is, the spot light SP is overlapped by a certain size

1/2, the sub-scanning speed (conveying speed) Vt of the substrate FS becomes

When the overlapping ratio Uo is 2/3, that is, the overlapping size of the spot light SP is set

At 2/3, Vt was 4800 μm/sec. Although not described in detail, the origin sensor 20 is similarly provided in the beam scanning devices MD2 to MD 6.

Fig. 10 is a sectional view showing a holding structure for holding the light beam scanning device MD by the 2 nd frame part Ub 2. Since the holding structure of the optical beam scanning device MD is the same for each optical beam scanning device MD, only the holding structure of the optical beam scanning device MD1 will be described, and the description of the holding structure of the other optical beam scanning devices MD will be omitted. Fig. 10 is also explained using three-dimensional coordinates of Xt, Yt, and Zt, as in fig. 7.

The beam scanning apparatus MD1 includes a support frame 40 that supports optical components (mirrors M10 to M15, a beam expander BE, a polarization beam splitter BS1, an image shift optical component SR, a deflection adjustment optical component DP, a field aperture FA, a λ/4 wavelength plate QW, cylindrical lenses CYa and CYb, a polygon mirror PM, an f θ lens FT, an optical lens system G10, and a photodetector DT1) as shown in fig. 7 and is rotatable about an irradiation center axis Le 1. The support frame 40 has a substantially U-shaped or C-shaped shape corresponding to the optical path of the beam LB1 passing through the beam scanning apparatus MD 1. The support frame 40 has 2

parallel support portions

42 and 44 arranged parallel to the XtYt plane and apart from and substantially parallel to the Zt direction, and a blocking support portion 46 blocking one end of the 2

parallel support portions

42 and 44. The closing support portion 46 is provided on the-Xt direction side of the

parallel support portions

42 and 44. The optical components of the beam scanning device MD (the mirror M10, the polygon mirror PM, the f θ lens FT, the mirror M15, the cylindrical lens CYb, and the like) are arranged along the outer peripheral surface of the support frame 40.

Although not shown, the mirrors M10, M11, the beam expander BE, the polarization beam splitter BS1, the optical lens system G10, and the photodetector DT1 are supported on the surface on the + Zt direction side of the parallel support portion 42. Similarly, although not shown, the image shift optical member SR, the deflection adjusting optical member DP, and the field aperture FA are supported on the surface on the-Xt direction side of the blocking support 46. Further, although not shown, the λ/4 wavelength plate QW, the cylindrical lenses CYa and CYb, the mirrors M14 and M15, the polygon mirror PM, the f θ lens FT, and the origin sensor 20 are supported on the surface on the-Zt direction side of the parallel support portion 44. Mirror M12 is supported on the surface parallel to the + Zt direction side of support portion 42 or the surface closing the-Xt direction side of support portion 46, and mirror M13 is supported on the surface closing the-Xt direction side of support portion 46 or the surface parallel to the-Zt direction side of support portion 44. The support frame 40 (particularly, the parallel support portion 44) supports the polygon mirror PM by supporting a polygon mirror driving portion RM (rotary motor).

On the other end side of the 2

parallel support portions

42 and 44 where the blocking support portion 46 is not provided, a cylindrical (circular tube) -shaped strut member BX1 constituting a part of the drawing device is provided in a state where insertion is performed. Between each of the

parallel support portions

42, 44 and the stay member BX1, an annular bearing 48 is mounted. The pillar member BX1 is supported in a state of being fixed to the 2 nd frame part Ub 2. Accordingly, the support bracket 40 can rotate about the column member BX1 with respect to the 2 nd frame portion UB2 of the body frame UB. The central axis of the column member BX1 is coaxial with the irradiation central axis Le1, and the outer ring portion of the annular bearing 48 that is a part of the drawing device is fixed to each of the

parallel support portions

42 and 44, and the inner ring portion of the annular bearing 48 is fixed to the outer peripheral surface of the column member BX 1. Of the annular bearings 48 at 2, the annular bearing 48 between the parallel support portion 42 at the + Zt direction side and the column member BX1 is constituted by, for example, a bevel ball bearing combined at the back, and the annular bearing 48 between the parallel support portion 44 at the-Zt direction side and the column member BX1 is constituted by a deep groove ball bearing. The beam scanning apparatus MD1 (including the support frame 40) is supported by the column member BX1 in a state of being inclined by θ with respect to the center plane Poc (fig. 1 and 4) at a position shifted in the + X (+ Xt) direction from the center of gravity position of the entire apparatus. As described above, the beam scanning apparatus MD1 is supported in a cantilever manner by the column member BX1 (the 2 nd frame part Ub2) provided at the position of the irradiation center axis Le 1.

The beam scanning apparatus MD1 includes a drive mechanism 50 for rotating the support frame 40 with respect to the 2 nd frame part Ub 2. The drive mechanism 50 is provided in the space between the 2

parallel support portions

42, 44. Thus, the optical beam scanning apparatus MD1 can be further miniaturized. This drive mechanism 50 is described in further detail with reference to fig. 11. The drive mechanism 50 includes a linear actuator 52, a movable member 54, a driven member 56, and springs 58 and 60. The linear actuator 52, the movable member 54, and the spring 58 are supported by a plate-shaped drive support member 62 parallel to the XtYt plane. At the end in the + Xt direction of the drive support member 62, a straight portion 62a extending in a plate shape in the + Zt direction in parallel to the YzZt plane is integrally provided. The vertical part 62a is fixed to a side surface Ub2a parallel to the YtZt plane of the 2 nd frame part Ub 2. Further, a U-shaped recess Ubx into which the column member BX1 is fitted and held is formed in the side surface Ub2a of the 2 nd frame part Ub2 so that the center line of the circular tube-shaped column member BX1 is coaxial with the irradiation center axis Le 1. The stay member BX1 fitted in the recess Ubx is fixed so as to be sandwiched between the vertical portion 62a of the drive support member 62 and the recess Ubx.

The driven member 56 is supported while being fixed to the inner surface side (+ Xt-direction side surface) of the blocking support portion 46 of the support frame 40. The driven member 56 abuts against a part of the movable member 54 that rotates upon receiving the linear thrust of the linear actuator 52, and receives a force in the-Yt direction. Accordingly, the entire beam scanning apparatus MD1 rotates about the stay member BX1 (irradiation center axis Le 1).

The configuration and operation will be described in further detail. The linear actuator 52 has a rod 52a which can advance and retreat in the Xt direction, and the rod 52a is advanced and retreated in the Xt direction by the control of the controller 18. The moving position of the rod 52a in the Xt direction is measured by a high-precision linear encoder or the like, and the measured value is sent to the control device 18. The movable member 54 is rotatable about a rotary shaft 54a provided in the drive support member 62. The movable member 54 has a 1 st contact portion 54b that contacts the roller 52b at the tip of the lever 52a, i.e., a roller (2 nd contact portion) 54c that contacts an end surface portion of the driven member 56 parallel to the XtZt plane. The extension spring 58 biases the 1 st contact portion 54b in the + Xt direction so that the roller 52b at the tip of the lever 52a and the 1 st contact portion 54b of the movable member 54 constantly come into contact with each other. Therefore, one end of the tension spring 58 is fixed to the drive support member 62, and the other end is fixed to the movable member 54 near the 1 st contact portion 54 b. The tension spring 60 generates a biasing force for pulling the roller 54c of the movable member 54 toward the driven member 56 so that the roller (2 nd contact portion) 54c pivotally supported in a rotatable manner on the movable member 54 and an end surface portion parallel to the XtZt plane of the driven member 56 are brought into contact with each other at any time. Therefore, one end of the tension spring 60 is fixed to the shaft portion of the roller 54c of the movable member 54, and the other end is fixed to the driven member 56.

When the rod 52a of the linear actuator 52 is positioned at the midpoint of the movement stroke in the Xt direction, the contact surface of the 1 st contact portion 54b of the movable member 54 in contact with the roller 52b and the contact surface of the end surface portion of the driven member 56 in contact with the roller 54c are set to be orthogonal to each other in the XtYt plane. As shown in fig. 11, when a line segment Pmc parallel to the Xt axis passing through the irradiation center axis Le1 is set when the rod 52a of the linear actuator 52 is at the neutral position, the center of gravity of the optical beam scanning device MD1 in the XtYt plane is set substantially on the line segment Pmc. Further, the rotation axis 54a of the movable member 54 and the axis of the roller 54c are also arranged on the line Pmc.

When the linear actuator 52 moves the lever 52a in the-Xt direction from the neutral position in fig. 11, the 1 st contact portion 54b of the movable member 54 is pressed by the roller 52b at the tip of the lever 52a against the biasing force of the spring 58, and therefore the movable member 54 rotates counterclockwise in the paper surface of fig. 11 about the rotation shaft 54 a. In this way, the roller 54c of the movable member 54 is pressed in the-Yt direction by the driven member 56. Therefore, the light beam scanning device MD1 (the support frame 40) rotates in the-Yt direction (also referred to as- θ zt rotation) around the irradiation center axis Le1 on the closing support 46 side. When the linear actuator 52 moves the lever 52a in the + Xt direction from the neutral position in fig. 11, the 1 st contact portion 54b of the movable member 54 moves in the + Xt direction while being held in contact with the roller 52b by the biasing force of the spring 58. Accordingly, the movable member 54 rotates clockwise in the paper plane of fig. 11 about the rotation shaft 54a, and the roller 54c of the movable member 54 moves in the + Yt direction. At this time, the driven member 56 moves in the + Yt direction while being held in contact with the roller 54c by the biasing force of the spring 60. Therefore, the closing support 46 side of the optical beam scanning device MD1 rotates in the + Yt direction (also referred to as + θ zt rotation) around the irradiation center axis Le 1.

In the present embodiment, since the distance from the rotation axis 54a of the movable member 54 to the 1 st contact portion 54b is set to be longer than the distance from the rotation axis 54a of the movable member 54 to the axis of the roller 54c, the amount of movement of the rod 52a of the linear actuator 52 in the Xt direction is reduced, and the amount of movement of the driven member 56 in the Yt direction is obtained. Further, since the distance from the center line (irradiation center axis Le1) of the mechanically rotation center circular tube-shaped column member BX1 of the optical beam scanning device MD1 to the driven member 56 to which the rotational driving force is applied can be made long, the rotational angle amount per unit movement amount of the rod 52a of the linear actuator 52 of the optical beam scanning device MD1 can be made sufficiently small, and the rotational angle setting of the optical beam scanning device MD1 can be controlled with high resolution (μ rad).

As shown in fig. 10 (or fig. 4) above, the beam scanning devices MD1 to MD6 are supported by a cylindrical column member BX1 and a ring bearing 48 so as to be rotatable coaxially with the irradiation center axes Le1 to Le6, with respect to the device main body (the 2 nd frame part Ub 2). Therefore, the beam scanning devices MD1 to MD6 are held by the device main body in the vicinity of the upper portions of the respective drawing lines SL1 to SL6 formed on the substrate FS, and the blocking support portion 46 sides of the beam scanning devices MD1 to MD6 are configured to be mechanically free from constraint (in a state of being loosely coupled to the device main body, the main body frame UB, or the like).

Therefore, even when the support frame 40 (particularly the 2 parallel support portions 42 and 44) serving as the structure of each of the light beam scanning devices MD1 to MD6 thermally expands due to a temperature change or the like, each of the light beam scanning devices MD1 to MD6 thermally expands mainly in the-Xt direction (the closed support portion 46 side) in fig. 10 and 11, and therefore, the drawing lines SL1 to SL6 are prevented from fluctuating in the direction of the outer peripheral surface of the rotary drum DR. That is, there is an advantage that the X-direction intervals between the odd-numbered drawing lines SL1, SL3, and SL5 and the even-numbered drawing lines SL2, SL4, and SL6 shown in fig. 3 are kept at a constant distance on the micrometer scale without being subjected to thermal deformation of the structure due to temperature change. Further, the frame 2 Ub2 and the column member BX1 supporting the beam scanning devices MD1 to MD6 are made of a metal material (e.g., indium steel) or a glass ceramic material (e.g., Zerodur) having a low thermal expansion coefficient, and thus a thermally stable structure can be obtained.

As described above, in the present embodiment, the circular tube-shaped column member BX1 and the annular bearing 48 shown in fig. 10 (or fig. 4) correspond to a rotation support mechanism for supporting the support frame 40 (i.e., the entire beam scanning apparatus MD) relative to the apparatus main body, i.e., the 2 nd frame part Ub2, so as to be rotatable about the irradiation center axes Le (Le1 to Le 6). In addition, in the present embodiment, the annular bearing 48 at the upper and lower portions 2 shown in fig. 10 corresponds to a coupling member for coupling the support frame 40 to the apparatus main body by restricting a portion of the support frame 40 (i.e., the entire optical beam scanning apparatus MD) supporting the apparatus main body (the 2 nd frame portion Ub2) to a region within a predetermined radius (here, a radius of an outer periphery of the annular bearing 48) from the irradiation center axis Le (Le1 to Le 6). In the structure shown in fig. 10, when the support frame 40 (the entire light beam scanning apparatus MD) can be firmly coupled to the 2 nd frame part Ub2 without rotating the support frame 40 (the entire light beam scanning apparatus MD) by θ zt with respect to the apparatus main body (the 2 nd frame part Ub2), the annular bearing 48 may be omitted, the upper end portion of the cylindrical support member BX1 may be coupled to the parallel support part 42, and the lower end portion of the support member BX1 may be coupled to the parallel support part 44. In this case, the pillar member BX1 having a circular tube shape with a predetermined radius from the irradiation center axis Le (Le1 to Le6) also functions as a coupling member.

Fig. 12 is a perspective view showing the state in which the column member BX1 and the drive support member 62 are attached to the 2 nd frame part Ub2 shown in fig. 4 (or fig. 10 and 11). The 2 nd frame part Ub2 is a rectangular pillar-shaped member extending in the Y direction, and a side surface Ub2a in the-X direction and a side surface Ub2b in the + X direction thereof are formed at an inclination angle ± θ with respect to the YZ plane, respectively (see fig. 4). A U-shaped recess Ubx into which the tubular pillar member BX1 is fitted is formed in the side surface Ub2a of the 2 nd frame portion Ub2 so as to penetrate the upper and lower sides of the side surface Ub2a, and is coaxial with the odd-numbered irradiation center axes Le1, Le3, and Le5 extending in the Zt direction. Similarly, a U-shaped recess Ubx into which the cylindrical pillar member BX1 is fitted is formed in the side surface Ub2b of the 2 nd frame portion Ub2 so as to penetrate the upper and lower sides of the side surface Ub2b, and is coaxial with the even-numbered irradiation center axes Le2, Le4, and Le6 extending in the Zt direction. Further, a vertical portion 62a (see fig. 10 and 11) integrated with the drive support member 62 is fixed to the side surfaces Ub2a and Ub2b so as to close the concave portions Ubx formed in the side surfaces Ub2a and Ub2b of the 2 nd frame portion Ub2, respectively. The 2 nd gantry unit Ub2 having such a structure is coupled to the 3 rd gantry unit Ub3, and the 3 rd gantry unit Ub3 is provided on the main body frames (main body frames BFa and BFb) of the exposure apparatus EX supporting the rotary drum DR and the alignment microscopes ALG1 to ALG 4.

Fig. 13 is a perspective view showing a structure in which the 3 rd frame part Ub3 shown in fig. 12 is attached to the main body frames BFa and BFb of the exposure apparatus EX. In fig. 4, 2 nd frame part Ub2 is provided in a suspended state below 1 st frame part Ub1 of main body frame Ub, and here, 2 nd frame part Ub2 is provided at a part of main body frame Ub to support main body frames BFa and BFb of rotary drum DR. The 3 rd frame part Ub3 has a gate structure including a corner-pillar-shaped horizontal part extending in the Y direction and fixed to the center of the 2 nd frame part Ub2 of the main body frame Ub in fig. 4, and corner-pillar-shaped leg parts extending in the Z direction at both ends in the Y direction. The legs on both sides of the 3 rd frame part Ub3 are supported by the main body frames BFa and BFb (also coupled to the main body frame Ub) of the exposure apparatus EX disposed at a distance in the Y direction. Although not shown in fig. 12, main body frames BFa and BFb are pivotally supported by bearings at positions spaced apart from 2 nd frame portion Ub2 in the-Z direction by shafts Sft protruding from both ends of rotary drum DR in the Y direction shown in fig. 2 or 4. The upper end surfaces of the body frames BFa and BFb are formed to have a predetermined width (for example, 5cm or more) in the Y direction.

One leg of the 3 rd frame part Ub3, here, the leg on the + Y direction side, is fixedly provided on the main body frame BFa through the chassis 500, but the leg on the + Y direction side of the 3 rd frame part Ub3 formed to be elongated in the Z direction may be directly fixedly provided on the main body frame BFa. A gyro member 501 having a V-shaped groove as a ridge line parallel to the Y axis is fixed to the lower end surface of the leg portion on the-Y direction side of the 3 rd frame portion Ub3, and a steel ball 502 fitted in the V-shaped groove of the gyro member 501 is supported on the upper surface of the main body frame BFb so as to be capable of rolling at this position. Therefore, the gyro member 501 and the steel ball 502 have a degree of freedom that can move relatively only in the Y direction along the V-groove. Further, a tension spring 503 for giving an urging force of the V-shaped groove of the top member 501 constantly contacting the steel ball 502 is provided between the protruding portion Ub4 of the leg side surface on the-Y direction side of the 3 rd frame portion Ub3 and the main body frame BFb, and the 3 rd frame portion Ub3 (and the 2 nd frame portion Ub2) is urged in the-Z direction.

In the case of the present embodiment, 3 total 6 beam scanning devices MD1 to MD6 having the same structure are provided on the 2 nd frame part Ub2 so as to be bilaterally symmetrical with respect to the center plane Poc (see fig. 4 and 5), and therefore the center of gravity of the entire exposure head 16 constituted by the 6 beam scanning devices MD1 to MD6 is located close to the center plane Poc in the X direction. Therefore, stress in the direction inclined in the X direction is less likely to occur in the leg portion of the 3 rd frame portion Ub3 that supports the load of the entire exposure head 16, and the deformation of the 3 rd frame portion Ub3 and the 2 nd frame portion Ub2 can be suppressed, so that the entire exposure head 16 can be stably held at the predetermined position.

Further, when the main body frames BFa and BFb are made of a general iron casting material, light metal (aluminum), or the like, instead of expensive metal having a low thermal expansion coefficient, the distance between the upper end portions of the main body frames BFa and BFb in the Y direction may vary by several micrometers due to changes in environmental temperature and the influence of heat-generating components (such as a motor, AOM, and electric substrate). Alternatively, the Y-direction interval of the main body frames BFa, BFb may vary in a range of several micrometers depending on the rotation period of the rotary drum DR due to slight eccentricity of the shaft Sft of the rotary drum DR, shaft offset of the motor or the reduction gear connected to the shaft Sft, mounting state of the bearing supporting the shaft Sft, and the like, and stress in the Y-direction may be generated in the main body frames BFa, BFb. Even when there is such a fluctuation in the main body frames BFa, BFb, as shown in fig. 13, since the 3 rd frame part Ub3 and the 2 nd frame part Ub2 are supported by the gyro member 501 and the steel ball 502 having a degree of freedom in the Y direction, even if there is such a fluctuation, it is possible to avoid the possibility that the 3 rd frame part Ub3 and the 2 nd frame part Ub2 are deformed.

As described above, the light beam scanning devices MD1 to MD6 can self-measure the tilt angles (tilt errors) of the scanning lines SL1 to SL6 using the photodetector DT1 shown in fig. 7 and the reference pattern formed on the surface of the rotary drum DR, respectively. Therefore, the control device 18 can drive the linear actuators 52 of the respective beam scanning devices MD (MD1 to MD6) in accordance with the measured inclination angles of the respective drawing lines SLn (SL1 to SL 6). Thus, the drawing lines SLn (SL1 to SL6) can be made parallel to each other, or the drawing lines SLn "(SL 1 to SL6) can be made parallel to the central axis AXo of the rotary drum DR. The controller 18 may detect the deformation of the substrate FS wound around the rotary drum DR or the deformation of the exposure area W based on the positions of the alignment marks MK (MK1 to MK4) on the substrate FS detected by using the alignment microscopes ALG (ALG1 to ALG4), and may drive the linear actuators 52 of the respective beam scanning apparatuses MD (MD1 to MD4) based on the detected deformations. Thus, the overlay accuracy of the pattern formed on the lower layer and the predetermined pattern newly exposed can be improved.

FIG. 14 is a view showing a state of deformation of an exposure area W in which a predetermined pattern is exposed by an exposure head 16. The deformation of the exposure field W is caused by the distortion of the substrate FS transported while being wound around the rotary drum DR. Even if the substrate FS is not warped, the exposure area W of the substrate FS may be distorted and deformed due to the substrate FS being transferred while the underlying pattern layer is formed.

As shown in FIG. 14, since the exposure region W is distorted, the alignment marks MK (MK 1-MK 4) are formed in a distorted state, not in a straight line. Further, an exposure region W' shown by a dotted line is an ideal exposure region showing almost no deformation. The controller 18 estimates the deformation of the exposure field W from the positions of the alignment marks MK (MK1 to MK4) on the substrate FS detected by using the alignment microscopes ALG (ALG1 to ALG4), and drives the linear actuators 52 of the respective beam scanning devices MD (MD1 to MD6) in accordance with the deformation state of the exposure field W. Immediately after the start of the drawing exposure using the drawing lines SL1 to SL6 for the exposure field W, the positions of the alignment marks MK2 and MK3 on the + X direction side of the observation regions Vw1 to Vw4 of the alignment microscopes ALG1 to ALG4 shown in fig. 3 can be detected, but the positions of the alignment marks MK2 and MK3 on the upstream side (on the (-X direction side) of the observation regions Vw1 to Vw4 cannot be detected when the drawing exposure is not sent on the substrate FS. Therefore, the controller 18 may estimate the deformation of the exposure field W of the current pattern to be exposed, based on the deformation amount and the deformation tendency obtained from the detection results of the positions of the alignment marks MK1 through MK4 attached around the previous exposure field W aligned in the longitudinal direction of the substrate FS, for example.

As described above, in the present embodiment, the beam scanning device MD can be rotated with high precision about the irradiation center axis Le passing through the midpoint (specific point) of the trace line SLn perpendicularly to the surface to be irradiated of the substrate FS, and therefore the inclination of the trace line SLn can be adjusted easily and precisely. In this way, since the drawing line SLn rotates on the irradiated surface of the substrate FS about the midpoint of the drawing line SLn, the inclination of the drawing line SLn can be easily adjusted while minimizing the positional variation of the drawing line SLn in the x (xt) direction and the y (yt) direction. For example, when the drawing line SLn is rotated with the position apart from the drawing line SLn as the center point, the position of the drawing line SLn is greatly moved so as to draw an arc with the center point as the center point. That is, the midpoint of the drawing line SLn is symmetrical by the positional variation of both ends after the inclination adjustment of the drawing line SLn.

Further, since it is not necessary to perform complicated tilt adjustment as disclosed in japanese unexamined patent application publication No. 8-11348, a positional shift between the main scanning direction and the sub-scanning direction due to the tilt adjustment does not occur. Even if the inclination of the scanning line SLn is adjusted, since the distance between the cylindrical lens CYb of the beam scanning device MD and the surface to be irradiated of the substrate FS is fixed, it is not necessary to perform complicated inclination adjustment as disclosed in japanese patent application laid-open No. 8-11348, and variation in magnification in the main scanning direction due to the inclination adjustment does not occur.

The irradiation center axis Le may be an axis passing through an arbitrary point (specific point) on the drawing line SLn perpendicularly to the surface to be irradiated of the substrate FS. In this case, although the drawing line SLn rotates about an arbitrary point on the drawing line SLn, the positional variation (lateral shift) of the drawing line SLn can be reduced as compared with the case where the center point is set at a position away from the drawing line SLn.

In the present embodiment, since the light beam LB is incident on the mirror M10 of the beam scanning apparatus MD so as to be substantially coaxial with the irradiation center axis Le passing perpendicularly through the midpoint of the scanning line SLn, the position of the light beam LB incident on the mirror M10 does not change even when the beam scanning apparatus MD rotates by θ zt around the irradiation center axis Le. Therefore, even when the optical beam scanning device MD is rotated by θ zt, the optical path of the light beam LB passing through the optical beam scanning device MD does not change, and the light beam LB can pass through the optical beam scanning device MD as accurately as desired. In this way, even if the beam scanning device MD is rotated by θ zt, there is no problem that the spot light SP cannot be projected onto the irradiation surface of the substrate FS due to the halo of the beam LB1 or the spot light SP is projected onto the position of the drawing line SLn after the inclination adjustment.

Optical components (such as the mirrors M10 to M15, the cylindrical lenses CYa and CYb, the polygon mirror PM, and the f θ lens FT) are supported by the support frame 40 of the beam scanning device MD, and the support frame 40 is supported so as to be rotatable with respect to the 2 nd frame part Ub 2. Further, since the linear actuator 52 supported by the 2 nd frame part Ub2 can be electrically controlled, the inclination of the drawing line SLn can be automatically adjusted electrically by visually detecting the position of the alignment mark MK and the measured inclination of the drawing line SLn.

In the optical configuration of the light beam scanning devices MD (MD1 to MD6) shown in fig. 7, the rotation center of the drawing line SLn (SL1 to SL6) is set at the midpoint of the drawing line SLn, but the rotation center may be shifted from the midpoint of the drawing line SLn. Specifically, in the configuration of fig. 7 (and fig. 10 and 11), for example, the mirror M10, the beam expander BE, the mirror M11, and the tubular pillar member BX1 (and the annular bearing 48) arranged along the optical axis AXa may BE moved in parallel from the position of fig. 7 (fig. 11) in the + Yt direction.

[ modified examples ]

The above embodiment may be modified as follows.

(modification 1) fig. 15 is a diagram showing an optical configuration of the optical beam scanning device MD in modification 1. The same reference numerals are given to the same components as those in fig. 7, and the description thereof will be omitted. Since the respective beam scanning apparatuses MD (MD1 to MD6) have the same configuration, only the beam scanning apparatus MD1 will be described, and the description of the other beam scanning apparatuses MD will be omitted.

The light beam scanning device MD1 includes a mirror M10, a beam expander BE, a mirror M20, a beam splitter BS2, a mirror M21, a polarizing beam splitter BS3, a λ/4 wavelength plate QW, mirrors M22 to M24, a cylindrical lens CYa, a polygon mirror PM, an f θ lens FT, a mirror M15, a cylindrical lens CYb, a photodetector DT1, and a position detector DT 2. In fig. 15, the image shift optical member SR and the deflection adjusting optical member DP are omitted.

The light beam LB1 incident on the light beam scanning device MD1 travels in the-Zt direction and enters the mirror M10. The beam LB1 incident on the beam scanning device MD1 is incident on the mirror M10 coaxially with the irradiation center axis Le 1. The function of the mirror M10, which is an incident optical member, is to reflect the incident light beam LB1 in the-Xt direction toward the mirror M20. The beam LB1 reflected by the mirror M10 passes through the beam expander BE and enters the mirror M20.

The mirror M20 reflects the incident beam LB1 toward the mirror M21 in the-Zt direction. The beam LB1 reflected by the mirror M20 enters the beam splitter BS 2. The beam splitter BS2 transmits a part of the incident light beam LB1 toward the mirror M21, and reflects the remaining part of the incident light beam LB1 toward the position detector DT 2. The beam splitter BS2 transmits a larger amount of light than the amount of light of the reflected light beam LB1 toward the mirror M21. For example, the ratio of the amount of transmitted light to the amount of reflected light is 9 to 1.

The mirror M21 reflects the incident beam LB1 in the + Xt direction toward the mirror M22. The beam LB1 reflected by the mirror M21 passes through the polarization beam splitter BS3 and the λ/4 wavelength plate QW and enters the mirror M22. The polarizing beam splitter BS3 transmits the P-polarized light beam and reflects the S-polarized light beam LB 1. Since the light beam LB1 incident on the light beam scanning device MD1 is a P-polarized light beam, the polarization beam splitter BS3 transmits the light beam LB1 from the mirror M21 toward the mirror M22.

The light beam LB1 whose optical path is bent by the reflection mirrors M22 to M24 is incident on the polygon mirror PM through the cylindrical lens CYa. The generatrix of the cylindrical lens CYa is set parallel to the XtYt plane, and the light beam LB1 is converged on the reflection surface RP of the polygon mirror PM having a rotation axis parallel to the Zt axis and extends in a slit shape in a direction parallel to the XtYt plane. The polygon mirror PM deflects the incident light beam LB1 and reflects the deflected light beam toward the + Xt direction side toward the f θ lens FT. The polygon mirror PM is rotated at a constant speed by a polygon mirror driving unit (motor) RM. The f θ lens FT having the optical axis AXf extending in the Xt-axis direction projects the spot light SP of the beam LB1 at an image height position on the irradiated surface of the substrate FS proportional to the incident angle thereof through the mirror M15 and the cylindrical lens CYb. The mirror M15 reflects the incident beam LB1 in the-Zt direction toward the substrate FS through the cylindrical lens CYb.

The light beam LB1 projected on the substrate FS is converged into a fine spot light SP having a diameter of about several μm (for example, 3 μm) on the surface to be irradiated of the substrate FS by the f θ lens FT and the cylindrical lens CYb having a bus line parallel to the Yt direction. Here, at least the f θ lens FT also functions as a projection optical system that projects the light beam LB1 deflected by the polygon mirror PM on the irradiated surface of the substrate FS. At least the reflecting members (the mirrors M15, M20 to M24) function as optical path deflecting members for deflecting the optical path of the light beam LB1 from the mirror M10 to the substrate FS. The optical path deflecting member can make the incident axis of the light beam LB1 incident on the mirror M10 substantially coaxial with the irradiation center axis Le1 passing through the midpoint of the drawing line SL1 in the Zt direction.

The reflected light from the rotary drum DR (or the substrate FS) passes through the cylindrical lens CYb, the mirror M15, the f θ lens FT, the polygon mirror PM, the cylindrical lens CYa, the mirrors M24 to M22, and the λ/4 wavelength plate QW, and enters the polarization beam splitter BS 3. Here, the light beam LB1 irradiated on the substrate FS is converted from P-polarized light to circularly polarized light beam LB1 by the λ/4 wavelength plate QW provided between the polarizing beam splitter BS3 and the substrate FS, specifically, between the polarizing beam splitter BS3 and the mirror M22, and the circularly polarized reflected light returning from the substrate FS to the polarizing beam splitter BS3 is converted from circularly polarized light to S-polarized light beam LB1 by the λ/4 wavelength plate QW. Therefore, the reflected light from the substrate FS is reflected by the polarization beam splitter BS3 and enters the photodetector DT 1. Thus, the inclination inherent to the drawing line SL1 of the optical beam scanning device MD1 can be detected by the same method as in the above-described embodiment.

The position detector DT2 is used to detect the center position of the incident beam LB1, and for example, a 4-division sensor is used. The 4-division sensor has 4 photodiodes (photoelectric conversion elements), and detects the center position of the light beam LB1 on an XtZt plane perpendicular to the traveling direction of the light beam LB1 using the difference (difference in signal level) between the amounts of light received by the 4 photodiodes. It is determined whether the light beam LB1 is displaced from the desired position. The image shift optical member SR or the deflection adjusting optical member DP described in the above embodiments may be provided between the mirror M10 and the beam splitter BS 2. In this way, the controller 18 can adjust the center position and the tilt of the beam LB1 based on the detection result of the position detector DT 2.

(modification 2) fig. 16 is a diagram showing an optical configuration of the optical beam scanning device MD in modification 2. Fig. 16 shows only the portion different from fig. 7 or 15, and the optical system in which many mirrors PM are located on the mirror M10 side is not shown. The same reference numerals are given to the same components as those in fig. 7 or 15, and the description thereof will be omitted. Since the respective beam scanning apparatuses MD (MD1 to MD6) have the same configuration, only the beam scanning apparatus MD1 will be described, and descriptions of the other beam scanning apparatuses MD will be omitted.

The beam scanning apparatus MD1 includes an image rotating optical system IR for rotating the drawing line SL1 about the irradiation center axis Le1 (about the midpoint of the drawing line SL 1). The image rotating optical system IR rotates around the irradiation center axis Le1, thereby rotating the drawing line SL 1. The image rotating optical system IR is provided between the cylindrical lens CYb and the irradiated surface of the substrate FS. As this image rotating optical system IR, for example, an image rotator may be used. The image rotating optical system IR is disposed so that the incident axis of the light beam LB1 passing through the midpoint of the scanning locus of the light beam LB1 incident on the image rotating optical system IR from the cylindrical lens CYb is substantially coaxial with the irradiation center axis Le 1. As a result, the scanning line SL1 can be rotated about the irradiation center axis Le1 by the rotating optical system IR. The image rotating optical system IR is rotated around the irradiation center axis Le1 by an actuator (driving unit), not shown, controlled by the control device 18.

The rotating optical system IR, although not shown, may be rotatably supported by a part of the parallel support portion 44 of the support frame 40 shown in fig. 10, for example. Therefore, even if the support frame 40 (the beam scanning apparatus MD1) is not configured to be rotatable about the irradiation center axis Le1, the tilt of the scanning line SL1 can be adjusted by rotating the image rotating optical system IR about the irradiation center axis Le 1. Further, the support frame 40 (the beam scanning apparatus MD1) may be configured to be rotatable about the irradiation center axis Le1, and the image rotating optical system IR may be configured to be rotatable about the irradiation center axis Le1 by θ zt independently of the support frame 40 (the beam scanning apparatus MD 1).

As described above, since the image rotation optical system IR alone can be rotated around the irradiation center axis Le1 in addition to the rotation of the beam scanning device MD1 around the irradiation center axis Le1, for example, after the tilt of the drawing line SL1 is roughly adjusted by the image rotation optical system IR, the tilt of the drawing line SL1 can be finely adjusted by the rotation of the entire beam scanning device MD 1. Therefore, the accuracy of the tilt adjustment of the drawing line SL1 can be improved. When the irradiation center axis Le1 is an axis passing through an arbitrary point on the scanning line SL1 perpendicularly to the surface to be irradiated of the substrate FS, the irradiation center axis Le1 can be made to pass through an arbitrary point on the scanning locus of the light beam LB1 incident from the cylindrical lens CYb on the image rotating optical system IR.

(modification 3) in modification 2, the beam scanning device MD (MD1 to MD6) is rotated around the irradiation central axis Le (Le1 to Le6), but the beam scanning device MD (MD1 to MD6) may not be rotated around the irradiation central axis Le (Le1 to Le 6). In this case, the 2 nd frame part Ub2 can hold the support frame 40 of the beam scanning device MD (MD1 to MD6) in a non-rotatable fixed state. This is because the light beam scanning apparatus MD (MD1 to MD6) can rotate the drawing lines SLn (SL1 to SL6) around the irradiation central axis Le (Le1 to Le6) by the image rotating optical system IR shown in fig. 16 without rotating around the irradiation central axis Le (Le1 to Le 6).

(modification 4) fig. 17A and 17B are diagrams showing an optical configuration of the optical beam scanning device MD in modification 4. In fig. 17A and 17B, the same reference numerals are given to the same components as those in fig. 7, and the description thereof will be omitted. Since the respective beam scanning apparatuses MD (MD1 to MD6) have the same configuration, only the beam scanning apparatus MD1 will be described, and the description of the other beam scanning apparatuses MD will be omitted. Fig. 17A shows the optical beam scanning device MD1 of modification 4 as viewed in a plane parallel to the XtZt plane, and fig. 17B shows the optical beam scanning device MD1 of modification 4 as viewed in a plane parallel to the YtZt plane.

The beam scanning device MD1 includes a cylindrical lens CYa, a reflection member RF, an f θ lens FT, a polygon mirror PM, and a cylindrical lens CYb. The light beam LB1 that travels in the-Zt direction and enters the light beam scanning device MD1 is set coaxially with the irradiation center axis Le1 that passes through the midpoint of the scanning line SL1 in parallel with the Zt axis. In modification 4, a lens system GLa is provided in front of the beam scanning device MD1 in the optical path of the beam LB1, and the beam LB1 is condensed into a spot light on a plane Cjp optically conjugate to the surface of the substrate FS. The light beam LB1 condensed on the conjugate plane Cjp is incident on the cylindrical lens CYa along the irradiation center axis Le1 while being emitted isotropically. The cylindrical lens CYa is set so that a generatrix is parallel to the Yt axis to have a refractive power in the Xt direction. The beam LB1 having just passed through the cylindrical lens CYa is converged to a substantially parallel beam in the Xt direction, and advances in the-Zt direction while maintaining the radial state in the Yt direction.

The upper reflecting surface RF1 of the reflecting member RF (inclined 45 ° to the XtYt plane) reflects the light beam LB1 in the-X direction so that the light beam LB1 incident through the cylindrical lens CYa is parallel to the optical axis AXf in the field of view area above the optical axis AXf of the incident f θ lens FT. The light beam LB1 passing through the upper side (+ Zt direction side) of the f θ lens FT enters the reflection surface RP (parallel to the Zt axis) of the polygon mirror PM. The reflection surface RP of the polygon mirror PM is provided at the same height position as the optical axis AXf in the Zt direction, and is set at the position of the pupil surface epf of the f θ lens FT or at a position near the pupil surface epf. Therefore, the rotation axis AXp of the polygon mirror PM and the optical axis AXf of the f θ lens FT are set to be orthogonal to each other in a plane parallel to the XtZt plane. The light beam LB1 incident on the polygon mirror PM is converged on the reflection surface RP in the non-scanning direction (Zt direction) orthogonal to the scanning direction (rotation direction) of the polygon mirror PM by the cylindrical lens CYa and the f θ lens FT, and is projected on the reflection surface RP in a slit-like distribution extending in a direction parallel to the Yt axis.

Since the reflection surface RP of the polygon mirror PM is parallel to the Zt axis (perpendicular to the optical axis AXf in the XtZt plane), the light beam LB1 reflected toward the + Xt direction at the reflection surface RP of the polygon mirror PM reaches the field of view area on the upper side (+ Zt direction side) of the optical axis AXf of the f θ lens FT, and the reflection surface RF2 (inclined 45 ° to the XtYt plane) faces the lower side of the reflection member RF through the field of view area on the lower side (-Zt direction side) of the optical axis AXf of the f θ lens FT. Therefore, the optical path of the light beam LB1 incident on the polygon mirror PM and the optical path of the light beam LB reflected by the polygon mirror PM are symmetrical with respect to the optical axis AXf in the XtZt plane. The light beam LB1 reflected by the lower reflecting surface RF2 of the reflecting member RF and traveling in the-Zt direction is converged into a spot light SP on the substrate FS by the cylindrical lens CYb having a refractive power in the Xt direction with a generatrix parallel to the Yt direction.

In the configuration of the beam scanning apparatus MD1 according to modification 4 shown in fig. 17A and 17B, since the optical path of the beam LB1 from the conjugate plane Cjp to the substrate FS (irradiated surface) is configured to be symmetrical with respect to the reflection surface RP (pupil surface epf) of the polygon mirror PM, the spot light SP projected on the substrate FS forms an image of the spot light of the beam LB1 condensed on the conjugate plane Cjp. Therefore, when one reflection surface RP of the polygon mirror PM is at an angle exactly orthogonal to the optical axis AXf, the light flux LB1 incident on the reflection surface RP of the polygon mirror PM from the f θ lens FT and the light flux LB1 incident on the f θ lens FT after being reflected on the reflection surface RP together with the light flux LB1 pass through the same optical path in the XtYt plane. At this time, the luminous flux LB1 irradiated on the lower reflecting surface RF2 of the reflecting member RF is the central portion of the reflecting surface RF2 in the Yt direction, and the point light SP of the luminous flux LB1 projected on the substrate FS is located at the midpoint on the drawing line SL1 (the point through which the irradiation center axis Le1 passes).

When the reflection surface RP of the polygon mirror PM is slightly inclined from a state perpendicular to the optical axis AXf in the XtYt plane due to the rotation about the rotation axis AXp of the polygon mirror PM, the light beam LB1 reflected by the reflection surface RP of the polygon mirror PM and reaching the reflection surface RF2 on the lower side of the reflection member RF by the f θ lens FT reflects that the rotation of the polygon mirror PM is shifted in the Yt direction on the reflection surface RF 2. In this way, even in the light beam scanning device MD1 of modification 4 shown in fig. 17A and 17B, the spot light SP can be scanned one-dimensionally along the scanning line SL 1. In the configuration of fig. 17A and 17B, although the upper reflective surface RF1 and the lower reflective surface RF2 of the reflective member RF are formed to be elongated in the Yt direction so as to cover the scanning range of the light beam LB1 along the drawing line SL1, when the reflective surface RF1 and the reflective surface RF2 are formed by different planar mirrors, respectively, the size in the Yt direction can be reduced to such an extent as to cover the diameter of the light beam LB1 incident from the lens system GLa.

The cylindrical lens CYa functions as an incident optical member for causing the light beam LB1 to enter the beam scanning apparatus MD 1. The f θ lens FT functions as a projection optical system that projects the light beam LB1 deflected by the polygon mirror PM on the surface of the substrate FS to be irradiated. The reflecting surface RF1 and the reflecting surface RF2 of the reflecting member RF function as an optical path deflecting member for deflecting the optical path of the light beam LB1 from the cylindrical lens CYa to the substrate FS. The optical path deflecting member can make the incident axis of the beam LB1 incident on the cylindrical lens CYa substantially coaxial with the irradiation center axis Le 1.

The optical components (cylindrical lenses CYa and CYb, reflecting member RF, polygon mirror PM, f θ lens FT, and the like) of the optical beam scanning apparatus MD1 shown in fig. 17A and 17B are supported by a support frame that can rotate about the irradiation center axis Le1, similarly to the support frame 40 shown in fig. 10 and 11. In the configuration of modification 4, similarly, even if the beam scanning apparatus MD1 rotates by θ zt around the irradiation center axis Le1, the position of the beam LB incident on the cylindrical lens CYa does not change. Therefore, even when the optical beam scanning device MD1 is rotated by θ zt, the optical path of the light beam LB passing through the optical beam scanning device MD1 does not change, and the light beam LB can pass through the optical beam scanning device MD1 as intended. In this way, even if the beam scanning apparatus MD1 is rotated by θ zt, problems such as the spot light SP not being projected onto the surface (irradiated surface) of the substrate FS due to the halo of the beam LB1 or the spot light SP being projected onto the position of the drawing line SLn after the inclination adjustment do not occur.

(modification 5) fig. 18A and 18B are diagrams showing an optical configuration of the optical beam scanning device MD in modification 5. In fig. 18A and 18B, the same components as those in fig. 17A and 17B are denoted by the same reference numerals, and description thereof will be omitted. Since the respective beam scanning apparatuses MD (MD1 to MD6) have the same configuration, only the beam scanning apparatus MD1 will be described, and the description of the other beam scanning apparatuses MD will be omitted. Fig. 18A shows the optical beam scanning device MD1 of modification example 5 viewed in a plane parallel to the XtYt plane, and fig. 18B shows the optical beam scanning device MD1 of modification example 5 viewed in a plane parallel to the YtZt plane.

The optical beam scanning apparatus MD1 of modification 5 is different from the optical beam scanning apparatus MD1 of modification 4 shown in fig. 17A and 17B in that the irradiation center axis Le1 is moved in parallel in the + Yt direction from the position of the midpoint of the drawing line SL 1. Therefore, the lens system GLa and the cylindrical lens CYa, which converge the light beam LB1 before entering the beam scanning device MD1 on the conjugate plane Cjp, are arranged to move in parallel in the + Yt direction integrally. In the case of modification 5, when the polygon mirror PM rotates clockwise, the light beam LB1 reflected by the reflection surface RP of the polygon mirror PM and irradiated on the reflection surface RF2 on the lower side of the reflection member RF through the f θ lens FT scans in the-Yt direction.

As described above, even if the configuration of modification 4 shown in fig. 17A and 17B is changed to modification 5 shown in fig. 18A and 18B, the beam scanning device MD1 can be rotated by θ zt about the irradiation center axis Le1 by setting the extension line of the irradiation center axis Le1 to pass through an arbitrary point (specific point) on the drawing line SL1, and the beam LB1 incident on the beam scanning device MD1 (cylindrical lens CYa) can be set to be coaxial with the irradiation center axis Le1, and even if the beam scanning device MD1 is rotated by θ zt, the spot light SP can be accurately scanned along the drawing line SL 1. Further, as is apparent from the configurations shown in fig. 18A and 18B, the position of the beam LB1 incident on the beam scanning device MD1 (cylindrical lens CYa) in the XtYz plane may be any position in the Yt direction as long as it is along the drawing line SL 1. Therefore, by extending the dimension of the cylindrical lens CYa in the generatrix direction, the position of the light beam LB1 incident on the light beam scanning device MD1 (cylindrical lens CYa) in the XtYz plane can be changed freely, and there is an advantage that the degree of freedom in setting the light guide path of the light beam LB1 can be increased. Further, since the position of the light beam LB1 incident on the light beam scanning device MD1 (cylindrical lens CYa) in the XtYz plane can be freely set in the Yt direction, the coaxiality between the mechanical rotation center axis (irradiation center axis Le1) of the light beam scanning device MD1 and the axis of the incident light beam LB1 can be accurately aligned in the Yt direction.

(modification 6) fig. 19 and 20 are views showing the optical configuration of the optical beam scanning device MD in modification 6. In fig. 19 and 20, the same reference numerals are given to the same components as those in fig. 7, and the description thereof will be omitted. Since the respective beam scanning apparatuses MD (MD1 to MD6) have the same configuration, only the beam scanning apparatus MD1 will be described, and the description of the other beam scanning apparatuses MD will be omitted. In fig. 7, since the direction parallel to the optical axis AXf of the f θ lens FT is set to the Xt direction, the scanning direction of the spot light SP is set to the Yt (y) direction, and the direction orthogonal to the Xt direction and the Yt direction is set to the Zt direction in fig. 19 and 20.

Fig. 19 shows the optical beam scanning apparatus MD1 of modification example 6 viewed in a plane parallel to the XtYt plane, and in modification example 6, the axis of the light beam LB1 (irradiation center axis Le1) incident on the optical beam scanning apparatus MD1 is set to be coaxial with the optical axis AXf of the f θ lens FT. That is, in the present modification, a mirror (reflection surface) for bending the light beam LB1 is not provided behind the f θ lens FT, but a scanning light beam emitted from the f θ lens FT and passing through the cylindrical lens CYb is directly projected onto the substrate FS.

In fig. 19, a light beam LB1 emitted from the light source device 14 and intensity-modulated (ON/OFF) by the drawing optical element AOM1 is guided to the cylindrical lens CYa through the lens system G30, the mirrors M30, M31, and the lens system G31. The beam LB1 incident on the beam scanning device MD1 is set to be coaxial with the irradiation center axis Le 1. The beam LB1 incident on the cylindrical lens CYa is shaped into a parallel beam having a predetermined cross-sectional diameter. The beam LB1 reflected by the mirror M14 from the cylindrical lens CYa and reaching the reflection surface RP of the polygon mirror PM becomes a beam converged by the cylindrical lens CYa in the Zt direction in a state of being parallel to the beam in the XtYt plane. The light beam LB1 reflected (polarized) by the polygon mirror PM is focused on the surface (irradiated surface) of the substrate FS by the f θ lens FT and the cylindrical lens CYb. In fig. 19, the optical axis AXf of the f θ lens FT is set parallel to the Xt axis in alignment with the irradiation center axis Le1, and the extension of the axis AXf and the irradiation center axis Le1 is orthogonal to the center axis (rotation center axis) AXo of the rotary cylinder DR.

The main body frame 300 supporting the optical beam scanning device MD1 of modification example 6 is formed with an opening 300A through which the optical beam LB1 scanned along the scanning line SL1 passes, and the optical beam scanning device MD1 is rotatably supported by the main body frame 300 through a ring bearing 301 whose radius from the optical axis AXf (irradiation center axis Le1) includes the size of the opening 300A. Since the center line of the annular bearing 301 is set to be coaxial with the optical axis AXf (irradiation center axis Le1), the optical beam scanning device MD1 rotates about the Xt axis around the optical axis AXf (irradiation center axis Le 1). This rotation is referred to as the thetaxt rotation.

Fig. 20 shows a state in which a plurality of beam scanning devices MD are arranged in the modification 6 shown in fig. 19, and when viewed in a plane parallel to the XZ plane, openings 300A for passing scanning beams from the odd-numbered beam scanning devices MD1, MD3, and MD5 are provided at a constant interval in the Y direction in the main body frame 300, and openings 300B for passing scanning beams from the even-numbered beam scanning devices MD2, MD4, and MD6 are provided at a constant interval in the Y direction. In modification 6 of fig. 20, the substrate FS wound around the rotary drum DR is horizontally conveyed in the-X direction, wound around about half a circumference from the upper part of the rotary drum DR, and then separated from the lower part of the rotary drum DR and conveyed in the + X direction. Therefore, here, the center plane Poc including the center axis AXo of the rotary drum DR is parallel to the XY plane.

In the configuration of modification 6, similarly, the mechanical rotation center of each of the beam scanning apparatuses MD formed by the ring bearing 301 is set as the irradiation center axes Le1 to Le6, and the light beams LB1 to LB6 incident on each of the beam scanning apparatuses MD are guided coaxially with the irradiation center axes Le1 to Le6, so that the posture positions of the light beams LB1 to LB6 incident on the lens system G30 do not change even when each of the beam scanning apparatuses MD rotates θ xt around each of the irradiation center axes Le1 to Le6, as in the previous embodiment and modifications. Therefore, even when the respective light beam scanning devices MD are rotated by θ xt, the optical paths of the light beams LB passing through the respective light beam scanning devices MD are not changed, and the light beams LB can pass through the light beam scanning devices MD as accurately as desired. In this way, even if the beam scanning apparatuses MD are rotated θ xt, there is no problem that the spot light SP cannot be projected on the surface (irradiated surface) of the substrate FS or the spot light SP is projected at positions deviated from the tilt-adjusted drawing lines SL1 to SL6 due to halation of the beams LB1 to LB 6.

The lens system G30 functions as an incident optical member for causing the light beam LB (LB1 to LB6) to enter the light beam scanning device MD (MD1 to MD 6). The f θ lens FT functions as a projection optical system for projecting the light beam LB1 deflected by the polygon mirror PM onto the surface of the substrate FS to be irradiated. The reflecting members (the mirrors M14, M30, and M31) function as optical path deflecting members for deflecting the optical path of the light beam LB (LB1 to LB6) from the lens system G30 to the substrate FS.

[ continuation error accompanying rotation adjustment of drawn line ]

In the above-described embodiment and the modifications, when the inclination of the drawing line SLn is adjusted by the θ zt rotation (or the θ xt rotation) of the optical beam scanning device MD, the position before the adjustment of the drawing start point and the drawing end point on the drawing line may be shifted from each other. Fig. 21 shows a state in which, for example, a drawing line SL1 of the optical beam scanning device MD1 in the initial state is parallel to the Yt axis is rotated by an angle θ ss in the opposite clock direction in the XtYt plane (irradiated surface). In fig. 21, the angle θ ss is exaggerated for convenience of explanation, but the maximum value of the actual rotatable angle θ ss is only about ± 2 °, which is extremely small. In fig. 21, assuming that the midpoint of the pre-adjustment drawing line SL1 is CC, the irradiation center axis Le1 extending in the Zt direction is set to pass through the midpoint CC, and the drawing line SL1 is set to rotate (tilt) θ Zt around the mechanical rotation center axis of the beam scanning apparatus MD1 that coincides with the irradiation center axis Le 1. Further, when the drawing start point of the drawing line SL1 is ST and the drawing end point is SE, the length LBL from the drawing start point ST to the drawing end point SE is the actual pattern drawing width in the Yt direction. Therefore, a length LBh from the drawing start point ST to the midpoint CC is equal to a length LBh from the midpoint CC to the drawing end point SE, and is LBh — LBL/2.

When the drawing line SL1 is rotated by the angle θ ss from the initial state, the drawing line SL1a is inclined with respect to the Yt axis. The drawing start point STa of the adjusted drawing line SL1a is shifted from the initial drawing start point ST (Δ XSa, Δ YSa), and the drawing end point SEa of the adjusted drawing line SL1a is shifted from the initial drawing end point SE (Δ XEa, Δ YEa). This positional deviation is a continuation error of the pattern drawn by the drawing line SL2 of the adjacent optical beam scanning device MD 2. For example, when the drawing line SL2 of the adjacent beam scanning device MD2 is positioned on the + Yt direction side with respect to the drawing line SL1a and it is necessary to perform subsequent exposure at the initial drawing start point ST, the adjusted drawing start point STa of the drawing line SL1a needs to be slightly shifted (shift) in the direction of the arrow Ar. The offset indicated by the arrow Ar can be realized by slightly advancing the timing of the start of the trace data after the time Tpx from the generation of the origin signal SH as illustrated in fig. 9.

Here, the amount of positional deviation Δ YSa is LBh · (1-cos (θ ss)), and when the amount of deviation (length) along the arrow Ar is Δ Ar, the amount of positional deviation Δ YSa and the amount of deviation Δ Ar become Δ YSa ═ Δ Ar · cos (θ ss), and therefore, the amount of deviation Δ Ar can be expressed as follows.

ΔAr＝〔LBh·(1－cos(θss))〕/cos(θss)···(1)

For example, when the length LBL is 50mm (LBh ═ 25mm), the offset amount Δ Ar at the angle θ ss of ± 0.5 ° is about 0.95 μm, the offset amount Δ Ar at the angle θ ss of ± 1.0 ° is about 3.8 μm, the offset amount Δ Ar at the angle θ ss of ± 2.0 ° is about 15.2 μm, and the change in the angle θ ss and the change in the offset amount Δ Ar have a 2-fold functional relationship. Therefore, the offset amount Δ Ar may be calculated from the adjusted angle θ ss, and the start of drawing data may be started by shortening the time Tpx described in fig. 9 by the time Δ Tpx corresponding to the offset amount Δ Ar (Δ Ar/the scanning speed Vss of the spot light SP).

When the drawing line SL2 of the adjacent beam scanning device MD2 is located on the-Yt direction side with respect to the drawing line SL1a and it is necessary to perform subsequent exposure at the initial drawing end point SE, the adjusted drawing end point SEa of the drawing line SL1a needs to be slightly shifted in the direction of the arrow Af. In this case, the amount of deviation Δ Af in the direction of arrow Af is also expressed by the following equation, as in the above equation (1)

ΔAf＝〔LBh·(1－cos(θss))〕/cos(θss)···(2)

And (4) obtaining. As shown in fig. 21, when the midpoint CC (Le1) is precisely set at the rotation center of the beam scanning device MD1, the absolute values of the shift amount Δ Ar and the shift amount Δ Af are equal to each other. Since the direction of the shift amount Δ Af is the same as the scanning direction of the spot light SP on the drawing line SL1a, in this case, the start of drawing data may be started by increasing the time Tpx described in fig. 9 by the time Δ Tpx (Δ Ar/scanning speed Vss of the spot light SP) corresponding to the shift amount Δ Af by the adjusted angle θ ss.

Further, the drawing start point STa of the drawing line SL1a adjusted by the angle θ ss is shifted by Δ XSa in the-Xt direction from the initial drawing start point ST, and the drawing end point SEa is shifted by Δ XEa in the + Xt direction from the initial drawing end point SE. Such positional deviation errors Δ XSa and Δ XEa in the Xt direction (sub-scanning direction) can be corrected by starting drawing each of the drawing lines SLn by adding an offset (offset) value of the error Δ XSa or Δ XEa to the measurement value (output value of the counter) of the encoder EC that measures the rotational angular position of the rotary drum DR. To perform such fine correction, the measurement and analysis capability (the amount of movement of the substrate FS counted by the counter circuit per 1) of the encoder EC (and the scale unit SD) with respect to the rotational angle position of the rotary drum DR is set to the size of the spot light SP

Is less than 1/2, preferably less than 1/10.

In the above description of fig. 21, when the plotting line SL1 of the optical beam scanning device MD1 in the initial state parallel to the Yt axis is rotated by the counterclockwise rotation angle θ ss in the XtYt plane (irradiated surface), the irradiation center axis Le1 is set to pass through the midpoint CC, and the plotting line SL1 (that is, the optical beam scanning device MD1) is set to rotate (tilt) by θ zt around the irradiation center axis Le 1. However, if there is a two-dimensional positional difference error Δ a (Δ Ax, Δ Ay) in the XtYt plane between the midpoint CC of the drawing line SL1 (the irradiation center axis Le1) and the mechanical rotation center axis Mrp of the optical beam scanning device MD1 due to an attachment error of the circular tubular column member BX1, the annular bearing 48, and the like, which determine the mechanical rotation center axis (hereinafter referred to as Mrp) of the optical beam scanning device MD1, and an error of the incident position of the optical beam LB1 into the optical beam scanning device MD1, the positional difference Δ a affects the errors (Δ XSa, Δ YSa), the errors (Δ XEa, Δ YEa) in fig. 21.

This state will be described with reference to fig. 22. Fig. 22 is a diagram showing an exaggerated state of the state of fig. 21, in which the mechanical rotation center axis (1 st rotation center axis) Mrp of the optical beam scanning device MD1 and the midpoint CC (irradiation center axis Le1) of the drawing line SL1 have a relative positional deviation error Δ a (Δ Ax, Δ Ay). In this case, the incident axis of the beam LB1 incident on the beam scanning device MD1 is coaxial with the rotation center axis Mrp. In fig. 22, the symbols and signs described with reference to fig. 21 are not described. As shown in fig. 22, in the initial state before adjustment, the drawing line SL1 that is originally parallel to the Yt axis is a drawing line SL1b that is inclined at the center angle θ ss with the rotation center axis Mrp of the position shift error (Δ Ax, Δ Ay) from the midpoint CC (Le 1). The drawing line SL1b is caused to move parallel to the XtYt plane by the drawing line SL1a shown in fig. 21 due to the influence of the errors (Δ Ax, Δ Ay). Therefore, the adjusted drawing starting point STb of the drawing line SL1b is shifted by the error Δ Xcc in the-Xt direction and by the error Δ Ycc in the + Yt direction from the drawing starting point STa in the state of fig. 21. Similarly, the drawing end point SEb of the adjusted drawing line SL1b is deviated by an error Δ Xcc in the-Xt direction and an error Δ Ycc in the + Yt direction from the drawing end point SEa in the state of fig. 21, and the midpoint CC 'of the adjusted drawing line SL1b (Le 1') is also deviated by an error Δ Xcc in the-Xt direction and an error Δ Ycc in the + Yt direction from the midpoint CC (Le1) of the drawing line SL1 in the state of fig. 21.

Therefore, the drawing start point STb of the adjusted drawing line SL1b is shifted in position in the Xt direction (Δ XSa + Δ Xcc) and in position in the Yt direction (Δ YSa- Δ Ycc) from the initial drawing start point ST, and the drawing end point SEb of the adjusted drawing line SL1b is shifted in position in the Xt direction (Δ XEa- Δ Xcc) and in position in the Yt direction (Δ YEa + Δ Ycc) from the initial drawing end point SE. The error components (Δ Xcc, Δ Ycc) due to the positional deviation of the rotation center axis Mrp from the midpoint CC (Le1) of the initial drawing line SL1 by the errors (Δ Ax, Δ Ay) are shown below when the midpoint CC of the initial drawing line SL1 is the origin (0, 0).

ΔXcc＝－ΔAy·sin(θss)+ΔAx· (1－cos(θss))· · · (3)

ΔYcc＝ΔAy· (1－cos(θss))+ΔAx·sin(θss) · · · (4)

As shown in fig. 22, when the incident axis of the light beam LB1 coincides with the rotation center axis Mrp and the midpoint CC (Le1) of the drawing line SL1 are shifted (shift) by the error (Δ Ax, Δ Ay) in the XtYt plane, the shift amounts Δ Ar, Δ Af of the drawing line SL1b may be calculated as described above with reference to fig. 21, and the start timing of the pattern data (drawing data) may be corrected by shortening or lengthening the time Tpx described with reference to fig. 9 by the corresponding time Δ Tpx. However, the length LBL (e.g., 50mm) from the drawing start point STb to the drawing end point SEb of the adjusted drawing line SL1b must be within the range of the maximum scanning length (e.g., 51mm) of the spot light SP. In the sub-scanning direction (Xt direction), correction can be performed by starting drawing of each of the drawing lines SLn in response to a value obtained by adding an error (Δ XSa + Δ Xcc) or an offset (offset) of (Δ XEa- Δ Xcc) to a measurement value (output value of a counter) of the encoder EC for measuring the rotational angle position of the rotary drum DR. In fig. 21 and 22, the case where the irradiation center axis Le1 passes through the midpoint CC of the drawing line SLn has been described as an example, but the irradiation center axis Le1 may pass through an arbitrary point on the drawing line SLn as in the modification 5. In this case, the same principle is applied to the calculation of the shift amounts Δ Ar and Δ Af of the drawing line SLn.

In addition, for example, in the case where the position of the light beam LB1 incident on the light beam scanning device MD1 in the XtYz plane is shifted in the Yt direction as in the case of the previous modification 5 (fig. 18A and 18B), when the mechanical rotation center axis Mrp and the irradiation center axis Le1 of the light beam scanning device MD1 are set at positions that coincide with or are very close to the drawing start point ST of the drawing line SL1, the adjusted drawing start point STb is hardly changed from the position of the initial drawing start point ST even if the drawing line SL1 is inclined at the angle θ ss. Therefore, when the adjusted drawing start point STb is continuous with the adjacent drawing line, the position adjustment of the spot light SP of the drawing line SL1b in the scanning direction (the adjustment of the time Tpx described in fig. 9) may not be necessary.

Further, it is preferable that the mechanical rotation center axis Mrp of the beam scanning device MD1 and the irradiation center axis Le1 are coaxial within a predetermined allowable range Δ Q (Δ Bx, Δ By) in the XtYt plane. The allowable range Δ Q is, for example, an actual position (actual position Apo) of the drawing start point STb (or the drawing end point SEb) of the adjusted drawing line SL1b when the optical beam scanning device MD1 is mechanically tilted by the predetermined angle θ sm, and a drawing start point of the drawing line SL1b when the optical beam scanning device MD1 is tilted by the angle θ sm when the allowable range Δ Q is assumed to be 0The difference between the designed positions (design positions Dpo) of the STb (or the drawing end point SEb) is set, for example, to the size of the spot light SP in the scanning direction (arrows Ar and Af in fig. 21) or the Yt direction of the spot light SP

Within. Here, the predetermined angle θ sm may be set to an upper limit angle (for example, ± 2 °) at which the optical beam scanning device MD1 can be mechanically rotated. In order to make the irradiation central axes Le (Le1 to Le6) and the rotation central axis Mrp of the respective beam scanning apparatuses MD (MD1 to MD6) coaxial within the predetermined allowable range Δ Q, at least one of the image shift optical member SR and the deflection adjusting optical member DP shown in fig. 7 may be provided between the mirrors M1 to M5 of the respective light introducing optical systems BDU (BDU1 to BDU6) shown in fig. 5. The central axis of the support member BX1 is set to be coaxial with the rotation central axis Mrp, or coaxial with the rotation central axis Mrp and the irradiation central axis Le within the predetermined allowable range Δ Q.

Further, the light beam LB is incident on the light beam scanning device MD so that the incident axis of the light beam LB incident on the light beam scanning device MD coincides with the rotation center axis Mrp, but the incident axis of the light beam LB incident on the light beam scanning device MD may be coaxial with the rotation center axis Mrp within the predetermined allowable range Δ Q. For example, the incident axis of the beam LB incident on the beam scanning device MD coincides with the irradiation center axis Le and is coaxial with the rotation center axis Mrp within the predetermined allowable range Δ Q.

In addition, the same applies to the image rotating optical system IR in the modifications 2 and 3, as long as the mechanical rotation center axis (2 nd rotation center axis) of the image rotating optical system IR and the irradiation center axis Le are coaxial within the predetermined allowable range Δ Q. In this case, the incident axis of the light beam LB passing through the scanning locus midpoint of the light beam LB incident on the image rotation optical system IR from the f θ lens FT is set to be coaxial with the mechanical rotation center axis of the image rotation optical system IR within the predetermined allowable range Δ Q.

In the configuration of the embodiment and the modifications described above, the light source device 14 is not mounted on the light beam scanning device MD that is rotatable with respect to the exposure device main body, but a small solid-state light source such as a semiconductor laser diode or an LED is provided in the light beam scanning device MD (for example, the support frame 40) as in a known device (japanese patent application laid-open No. h 08-011348), and the solid-state light source is controlled to emit light in pulses based on drawing data. In this case, the drawing optical element AOM shown in fig. 5 and 6 is not required.

Further, in the above-described embodiments and modifications, the intensity modulation (ON/OFF) of the spot light SP based ON the drawing data is performed by the drawing optical elements AOM (AOM1 to AOM6) provided in the light guide optical system BDU (BDU1 to BDU6) in fig. 5, for example, but when the light source device 14 is a fiber amplifier laser light source, the intensity of the seed light (pulse light) in the infrared wavelength band before entering the fiber amplifier may be modulated into the burst wave form based ON the drawing data, so that the pulse light itself of the ultraviolet light output from the light source device 14 is modulated into the burst wave form based ON the drawing data. In this case, the drawing optical element AOM provided in the light introducing optical system BDU is used as a selection optical element (referred to as a switching element AOM) for determining whether or not to guide the light beam LB from the light source device 14 to the beam scanning device MD. Therefore, it is necessary to synchronize the rotational speeds of the polygon mirrors PM of the respective optical beam scanning devices MD and control the rotational angles so that the phases thereof also maintain a predetermined relationship. Further, it is preferable to provide a beam transmitting system (such as a mirror) for allowing the beam LB from the light source device 14 to sequentially pass through the switching elements AOM of the beam scanning device MD, and to perform synchronous control for sequentially turning ON any of the switching elements AOM during one scanning of the spot light SP ON the drawing line SLn in response to the origin signal SH of the polygon mirror PM.

In the exposure apparatus EX according to the above-described embodiment and the modifications, although the spot light SP is drawn and exposed by the beam scanning apparatus MD on the substrate FS supported in a curved shape by the rotary drum DR, the spot light SP may be drawn and exposed on the substrate FS supported in a flat shape. That is, the beam scanning device MD may perform the drawing exposure of the spot light SP on the substrate FS supported in a planar shape. The mechanism for supporting the substrate FS in a flat shape can be the one disclosed in International patent publication No. 2013/150677 pamphlet. In short, the area of the endless belt supporting substrate FS is defined to be flat by a plurality of rollers around which the endless belt is wound. In the planar region of the endless belt, the substrate FS to be conveyed is closely attached to the endless belt and supported. Since the endless belt is conveyed in an endless manner in a predetermined direction, the endless belt can convey the supported substrate FS in the conveyance direction of the substrate FS.

(embodiment 2)

Fig. 23 shows the structure of the optical beam scanning device MD 'according to embodiment 2, and the optical beam scanning device MD' in fig. 23 is replaceable with the optical beam scanning devices MDn (MD1 to MD6) shown in fig. 5, 7, 10, and the like. The components constituting the optical beam scanning device MD' of fig. 23 are the same as those of the optical beam scanning device MDn described above, and the detailed description thereof will be omitted. The beam scanning apparatus MD' according to embodiment 2 is configured to introduce the light beam LBn (LB1 to LB6) transmitted through the single-mode optical fiber SMF of the post-condensed light beam LBn (LB1 to LB6) of the drawing optical elements AOMn (AOM1 to AOM6) entering the light introduction optical system (also referred to as beam distribution optical system) BDUn (BDU1 to BDU 6).

The exit end Pbo of the optical fiber SMF is fixed to the + Zt direction of the mirror M10 of the beam scanning device MDn, and the light beam LB1 condensed at the exit end Pbo is reflected by the mirror M10 while being emitted at a predetermined Numerical Aperture (NA) and incident on the condenser lens BE1 and the collimator lens BE2 constituting the beam expander BE. The light beam LB1 is condensed at a condensing position Pb1 between the condenser lens Be1 and the collimator lens Be2, and then the light beam LB1, which is again radiated, enters the collimator lens Be2 and is converted into a parallel light beam. The beam LB1 emitted from the collimator lens Be2 passes through the mirror M12, the image shift optical element SR, the deflection adjusting optical element DP, the field aperture FA, the mirror M13, the λ/4 wavelength plate QW, the cylindrical lens CYa, the mirror M14, the polygon mirror PM, the f θ lens FT, the mirror M15, and the cylindrical lens CYb, and is condensed into the spot light SP on the substrate FS, as in the case of the foregoing fig. 7. The surface on which the spot light SP is formed (the surface of the substrate FS) is optically conjugate with the light collecting position Pb1 and the emission end PBo. In fig. 23, the mirror M11, the polarization beam splitter BS1, the lens system G10, and the photodetector DT1 shown in fig. 7 are omitted.

In embodiment 2, the beam scanning apparatus MD' is also supported by the column member BX1 so as to be rotatable within a predetermined angular range about the irradiation center axis Le1 as a whole, but the emission end Pbo of the optical fiber SMF can be fixed at an arbitrary position shifted from the irradiation center axis Le 1. When a pattern is drawn by scanning a light beam in an ultraviolet wavelength band at high speed, the energy of the light beam (illuminance per unit area of spot light) may need to be set to be considerably high depending on the sensitivity of the photosensitive functional layer on the substrate FS. Therefore, in the optical transmission using the single mode optical fiber SMF as shown in fig. 23, the resistance of the optical fiber against ultraviolet rays may not be ensured. However, when the photosensitive functional layer has sensitivity to light having a wavelength longer than the ultraviolet wavelength band, for example, a wavelength of 500nm to 700nm, the light can be transmitted through the single mode optical fiber SMF as shown in fig. 23.

The incident end, not shown, of the optical fiber SMF shown in fig. 23 is arranged behind the branching mirror M1 previously guided by the drawing optical element AOMn in the optical waveguide optical system BDUn shown in fig. 5. Specifically, the drawing light beam LBn reflected by the mirror M1 may be converted into a light beam condensed at a predetermined NA (numerical aperture) by a condenser lens, and the incident end of the optical fiber SMF may be fixed at the condensing point (light waist position).

Claims

1. A pattern drawing device for drawing a pattern on a substrate by two-dimensionally scanning a spot light on the substrate in a main scanning direction and a sub-scanning direction while modulating the intensity of a light beam from a light source device projected as the spot light on the surface of the substrate based on drawing data corresponding to the pattern to be drawn on the substrate, the pattern drawing device comprising:

an incident optical member for receiving a light beam for drawing intensity-modulated based on the drawing data;

a scanning deflecting unit that deflects the drawing light beam from the incident optical unit for one-dimensional scanning in the main scanning direction;

a projection optical system that causes the deflected drawing light beam to be incident thereon and to be projected as the spot light onto the substrate;

a support frame integrally supporting the incident optical member, the scanning deflection member, and the projection optical system as a beam scanning unit;

a rotation support mechanism for supporting the support frame on the apparatus body in a state of being rotatable around a 1 st rotation center axis parallel to a normal line of the substrate surface of a support member provided on the apparatus body; and

and a light introduction optical system that guides the drawing light beam to the incident optical member such that an incident axis of the drawing light beam incident on the incident optical member is coaxial with the 1 st rotation center axis within a predetermined allowable range.

2. The pattern drawing apparatus according to claim 1, wherein the support frame supports the plurality of optical path deflecting members that bend the optical paths of the drawing light beams from the incident optical member to the substrate so that the 1 st rotation center axis and the irradiation center axis are set to be coaxial within the predetermined allowable range, when a normal line of a specific point on a scanning line defined by one-dimensional scanning of the point light in the main scanning direction among normal lines passing through the surface of the substrate is set as the irradiation center axis.

3. The pattern drawing apparatus according to claim 2, wherein the support includes an image rotating optical system which is provided between the substrate and the projection optical system and is supported rotatably with respect to the support around a 2 nd rotation center axis which is coaxial with the irradiation center axis within the predetermined allowable range.

4. The pattern drawing apparatus according to claim 3, further comprising a conveyance mechanism for supporting the substrate and moving the substrate at a predetermined speed in the sub-scanning direction;

the support frame and the rotation support mechanism constituting the light beam scanning unit are provided in plurality at predetermined intervals in the main scanning direction, and the patterns drawn on the substrate by one-dimensional scanning of the spot light projected from each of the plurality of light beam scanning units are attached to a main body frame in the apparatus main body so as to be joined in the main scanning direction in accordance with movement of the substrate by the transport mechanism.

5. The pattern drawing device according to claim 4, wherein a plurality of the light introduction optical systems are provided corresponding to the plurality of the light beam scanning units, respectively;

a plurality of mirrors set so that the light beam for drawing is directed toward the incident optical member, and an acousto-optic modulator that emits, as the light beam for drawing, primary diffracted light generated when the light beam introduced from the light source device is diffracted in synchronization with the timing of scanning of the spot light in the main scanning direction;

the mirror disposed behind the acousto-optic modulator among the plurality of mirrors is disposed to reflect only the primary diffracted light toward the incident optical member.

6. The pattern drawing device according to claim 5, further having beam splitters that direct the light beams from the light source device toward respective branches of the plurality of light introducing optical systems;

the acousto-optic modulator provided in each of the plurality of light introducing optical systems is applied with a high frequency signal for generating the primary diffracted light and modulated based on the drawing data corresponding to the pattern.

7. The pattern drawing device according to claim 5, wherein the light source device comprises: a semiconductor laser element for outputting a seed light in an infrared wavelength range pulsed at a predetermined frequency, an optical fiber amplifier for amplifying the seed light, and a wavelength conversion element for converting the amplified seed light in a pulse form in the infrared wavelength range into a pulse light in an ultraviolet wavelength range;

an optical fiber amplifying laser light source for emitting the pulsed light in the ultraviolet wavelength range as the light beam for drawing by modulating the intensity of the light based on the drawing data.

8. The pattern drawing apparatus according to claim 5, wherein a light beam transmission system is provided, the light beam transmission system sequentially transmitting a light beam from the light source device through each of the acousto-optic modulators provided in each of the plurality of light introduction optical systems;

any one of the plurality of acousto-optic modulators is selectively switched to be in a conducting state by the primary diffracted light.

9. The pattern drawing device according to any one of claims 1 to 8, wherein the scanning deflecting member is a rotary polygon mirror that repeatedly deflects the drawing light beam in the main scanning direction;

the projection optical system is an f θ mirror for condensing the drawing light beam deflected by the rotary polygon mirror on the substrate as the spot light and scanning in a telecentric state in the main scanning direction;

the support frame of the beam scanning unit holds the f θ mirror such that the extension of the optical axis of the f θ mirror is orthogonal to the 1 st rotation center axis.

10. The pattern drawing apparatus according to claim 9, wherein the support frame of the beam scanning unit supports a mirror that bends the drawing beam emitted from the f θ mirror so as to be projected onto the surface of the substrate in a state parallel to the 1 st rotation center axis, and a 2 nd cylindrical lens disposed between the mirror and the substrate.

11. The pattern drawing apparatus according to claim 10, wherein the incident optical member provided in the light beam scanning unit is a mirror that reflects the drawing light beam from the light-guiding optical system in a direction parallel to the optical axis of the f θ mirror;

the support frame supports a beam expander that expands a diameter of the drawing beam reflected by the mirror, and a 1 st cylindrical lens that is disposed on an optical path between the beam expander and the rotary polygon mirror and converges the drawing beam on a reflection surface of the rotary polygon mirror in a slit shape.

12. The pattern drawing apparatus according to any one of claims 1 to 8, wherein an actuator for rotating the beam scanning unit supported by the rotary support mechanism with respect to the apparatus body is disposed inside the support frame.