JP5722136B2 - Pattern drawing apparatus and pattern drawing method - Google Patents

Description

  The present invention relates to a technique for drawing a pattern by irradiating a substrate with spatially modulated light.

  Conventionally, a pattern is formed by irradiating various substrates such as a semiconductor substrate, a printed wiring substrate, and a glass substrate with light through a mask. In recent years, in order to cope with the formation of various patterns, a technique for drawing a pattern by directly irradiating a substrate with spatially modulated light without using a mask has been used.

  As one of the spatial light modulators, a reflective and diffraction grating type in which flexible ribbons and fixed ribbons are alternately arranged is known. For example, Patent Document 1 discloses an image recording apparatus that records an image on a photosensitive material using such a spatial light modulator. When an image is recorded by such a spatial light modulator, usually, a plurality of pairs of movable ribbons and fixed ribbons function as one light modulation element, and the plurality of light modulation elements are arranged in a line. Therefore, with respect to the sub-scanning direction corresponding to the arrangement direction of the light modulation elements, drawing cannot be performed with the resolution of the drawing position (hereinafter referred to as “position resolution”) that is equal to or smaller than the size corresponding to the light modulation elements. . In the main scanning direction perpendicular to the sub-scanning direction, the position resolution can be increased by slowing the moving speed of the photosensitive material or shifting the drawing timing.

  In the image recording apparatus of Patent Document 1, each pair of a movable ribbon that moves up and down by bending and a fixed ribbon is a lattice element as a control unit, and the movable ribbon is controlled independently for each lattice element. An image is recorded with high position resolution in the sub-scanning direction.

JP 2007-121881 A

  When using a diffraction grating type spatial light modulator, a grating element that irradiates light to the photosensitive material and a grating that does not irradiate light in order to further increase the position resolution or slightly shift the light beam. If the method of irradiating the light-sensitive material with half the intensity of light from the lattice element between the elements is used, there arises a problem that the pattern line width drawn greatly changes with respect to the up and down vibration of the substrate.

  The present invention has been made in view of the above problems, and suppresses a decrease in the allowable range of the position of the drawing surface in the optical axis direction even when drawing with high positional resolution using a spatial light modulator. The purpose is to do.

  The invention according to claim 1 is a pattern drawing apparatus, comprising: a support unit that supports a substrate; a light irradiation unit that irradiates the substrate with spatially modulated light; and the substrate with respect to the light irradiation unit. A relatively moving moving mechanism; and a light emitting unit and a drawing data generating unit that generates data for controlling the moving mechanism, wherein the light irradiating unit includes a light source and a plurality of lattice elements in a line. A spatial light modulator of a diffraction grating type and a reflection type arranged, and a relative movement direction of the substrate by the moving mechanism intersects a direction on the substrate corresponding to an arrangement direction of the plurality of grating elements. Each of the plurality of lattice elements is a combination of one fixed reflective surface and one movable reflective surface extending in a direction perpendicular to the arrangement direction, and the movable reflective surface is the movable reflective surface Can move in a direction perpendicular to Each of the plurality of grating elements has a half-wavelength difference between an optical path passing through the movable reflecting surface and an optical path passing through the fixed reflecting surface that is an integer multiple of 0 or more times the wavelength of the light. A first state with an added length, a second state in which the optical path length difference is the integer multiple of the wavelength of the light, a third state between the second state and the first state, And a fourth state between the third state and the second state, and the drawing data generation unit can include a plurality of instructions associated with the plurality of grid elements, respectively. In the value, an instruction value for instructing the lattice element for the first state, an instruction value for instructing the lattice element for the third state, and an instruction value for instructing the lattice element for the second state are in this order. When arranged, at least one continuous with the instruction value indicating the third state An instruction value for instructing the second state, changing to an instruction value for instructing the fourth state.

  Invention of Claim 2 is a pattern drawing apparatus of Claim 1, Comprising: The optical path length difference of the optical path which passes along the said movable reflective surface between the said 3rd state and the said 2nd state is , 1/4 of the wavelength.

Invention of Claim 3 is a pattern drawing apparatus of Claim 2, Comprising: The instruction value which instruct | indicates three said 2nd states following the said instruction value which instruct | indicates the said 3rd state, The instruction value is changed to an instruction value indicating the fourth state .

  Invention of Claim 4 is a pattern drawing apparatus of Claim 3, Comprising: The optical path length difference of the optical path which passes along the said movable reflective surface between the said 4th state and the said 2nd state is 1/6 of the wavelength.

  A fifth aspect of the present invention is the pattern drawing apparatus according to any one of the first to fourth aspects, wherein the substrate is a semiconductor substrate.

  Invention of Claim 6 is a pattern drawing method, Comprising: a) The process which moves a board | substrate relatively with respect to a light irradiation part, b) In parallel with the said a) process, from the said light irradiation part Irradiating the substrate with spatially modulated light, and the light irradiating unit includes a light source and a diffraction grating type and reflective spatial light modulator in which a plurality of grating elements are arranged in a line, The relative movement direction of the substrate with respect to the light irradiation unit is a direction intersecting a direction on the substrate corresponding to the arrangement direction of the plurality of lattice elements, and each of the plurality of lattice elements is arranged in the arrangement direction. Each of the plurality of grating elements, each of which is movable in a direction perpendicular to the movable reflective surface. Is an optical path passing through the movable reflecting surface A first state in which the optical path length difference from the optical path passing through the fixed reflecting surface is a length obtained by adding a half wavelength to an integer multiple of 0 times or more of the wavelength of the light, and the optical path length difference of the wavelength of the light A second state that is an integer multiple, a third state between the second state and the first state, and a fourth state between the third state and the second state In the step b), the lattice element in the first state, the lattice element in the third state, and the lattice element in the fourth state are arranged in this order.

  The invention according to claim 7 is the pattern drawing method according to claim 6, wherein an optical path length difference of an optical path passing through the movable reflecting surface between the third state and the second state is , 1/4 of the wavelength.

  The invention according to claim 8 is the pattern drawing method according to claim 7, wherein the three lattice elements in the fourth state are arranged in succession.

  The invention according to claim 9 is the pattern drawing method according to claim 8, wherein an optical path length difference of the optical path passing through the movable reflecting surface between the fourth state and the second state is different. 1/6 of the wavelength.

  A tenth aspect of the present invention is the pattern drawing method according to any one of the sixth to ninth aspects, wherein the substrate is a semiconductor substrate.

  ADVANTAGE OF THE INVENTION According to this invention, when drawing a pattern with high position resolution, the fall of the allowable range of the position of the drawing surface in an optical axis direction can be suppressed.

It is a front view of a pattern drawing apparatus. It is a top view of a pattern drawing apparatus. It is a block diagram which shows the electric constitution of a pattern drawing apparatus. It is a figure which shows the structure of an optical unit. It is a figure which shows a spatial light modulator. It is a figure which shows the spatial light modulator of OFF state. It is a figure which shows the spatial light modulator of a partial ON state. It is a figure which shows the flow of preparation work and operation | movement of a pattern drawing apparatus. It is a figure which shows a part of run length data. It is a figure which shows a part of run length data. It is a figure which shows the lattice element of an ON state and an OFF state. It is a figure which shows the arrangement | sequence of a lattice element. It is a figure which shows the arrangement | sequence of a lattice element. It is a figure which shows the lattice element of an intermediate | middle state and an incomplete ON state. It is a figure which shows the arrangement | sequence of a lattice element. It is a figure which shows the relationship between the distance from drawing reference | standard height and line | wire width at the time of changing the number of the lattice elements of an incomplete ON state. It is a figure which shows the relationship between the position of a subscanning direction, and light intensity. It is a figure which shows the relationship between the distance from drawing reference | standard height and line | wire width at the time of changing the number of the lattice elements of an incomplete ON state. It is a figure which shows the relationship between the distance from drawing reference | standard height and line | wire width at the time of changing the number of the lattice elements of an incomplete ON state. It is a figure which shows the relationship between the distance from drawing reference height at the time of changing phase difference, and line | wire width. It is a figure which shows the relationship between the distance from drawing reference height at the time of changing phase difference, and line | wire width. It is a figure which shows the relationship between the distance from drawing reference height at the time of changing phase difference, and line | wire width. It is a figure which shows the relationship between a phase difference and the inclination of the graph shown to FIG.

  FIG. 1 is a front view of a pattern drawing apparatus 100 according to an embodiment of the present invention, and FIG. 2 is a plan view. FIG. 3 is a block diagram showing an electrical configuration of the pattern drawing apparatus 100. The pattern drawing apparatus 100 is an apparatus for drawing a pattern by irradiating light onto a drawing surface which is the upper surface of a semiconductor substrate 9 on which a layer of a photosensitive material such as a resist is formed. The substrate 9 may be other various substrates such as a printed circuit board, a color filter substrate, a glass panel for flat panel display provided in a liquid crystal display device or a plasma display device, and an optical disk substrate. In the example of FIG. 1, the pattern is drawn so as to overlap with the base pattern formed on the surface of the circular semiconductor substrate. The drawing pattern is, for example, a wiring pattern extending from the integrated circuit in order to connect the integrated circuit to the outside.

  In the pattern drawing apparatus 100, the inside of the main body is formed by attaching cover panels (not shown) to the ceiling surface and the peripheral surface of the skeleton of the main body frame 101, and various components are arranged inside and outside the main body. . The inside of the main body of the pattern drawing apparatus 100 is divided into a processing area 102 and a delivery area 103. Among these regions, the stage 10, the stage moving mechanism 20, the stage position measuring unit 30, the optical unit 40, the alignment unit 361, and the control unit 60 are arranged in the processing region 102. In FIG. 2, the control unit 60 is depicted outside. In the delivery area 103, a transfer device 110 such as a transfer robot for carrying the substrate 9 in and out of the processing area 102 is arranged. The control unit 60 is electrically connected to each unit (drawing engine) included in the pattern drawing apparatus 100 and controls operations of these units.

  An illumination unit 362 is disposed outside the main body of the pattern drawing apparatus 100. The illumination unit 362 supplies illumination light to the alignment unit 361.

  A cassette placement unit 104 is disposed outside the main body of the pattern drawing apparatus 100 at a position adjacent to the transfer area 103. A cassette 90 is placed on the cassette placement unit 104. The transfer device 110 is provided at a position corresponding to the cassette placement unit 104, takes out the unprocessed substrate 9 accommodated in the cassette 90 placed on the cassette placement unit 104, and loads it into the processing region 102 (loading). At the same time, the substrate 9 is unloaded from the processing region 102 and stored in the cassette 90. Delivery of the cassette 90 to the cassette mounting unit 104 is performed by an external transport device (not shown). Loading of the unprocessed substrate 9 and unloading of the processed substrate 9 are performed by operating the transfer device 110 in accordance with an instruction from the control unit 60.

  The stage 10 is a support portion that has a flat outer shape and supports the substrate 9 placed on the upper surface thereof in a horizontal posture. A plurality of suction holes are formed on the upper surface of the stage 10, and the substrate 9 placed on the stage 10 is fixed to the upper surface of the stage 10 by applying a negative pressure (suction pressure) to the suction holes. Hold. Various other mechanisms for supporting the substrate 9 may be employed. The stage 10 is moved in the horizontal direction by the stage moving mechanism 20.

  The stage moving mechanism 20 moves the stage 10 in the main scanning direction (Y-axis direction), the sub-scanning direction (X-axis direction), and the rotation direction (rotation direction around the Z axis (θ-axis direction)). Thereby, the substrate 9 supported by the stage 10 moves relative to the optical unit 40. The stage moving mechanism 20 supports a rotating mechanism 21 that rotates the stage 10, a support plate 22 that supports the rotating mechanism 21, a sub-scanning mechanism 23 that moves the support plate in the sub-scanning direction, and a sub-scanning mechanism 23. A base plate 24 and a main scanning mechanism 25 that moves the base plate 24 in the main scanning direction are provided. The rotation mechanism 21 rotates the stage 10 on the support plate 22 around a rotation axis perpendicular to the upper surface of the substrate 9. As shown in FIG. 3, the rotation mechanism 21, the sub-scanning mechanism 23, and the main scanning mechanism 25 are electrically connected to the irradiation control unit 61 of the control unit 60, and the stage 10 is moved according to an instruction from the irradiation control unit 61. Moving.

  The sub-scanning mechanism 23 has a linear motor 23a. The linear motor 23 a includes a mover attached to the lower surface of the support plate 22 and a stator laid on the upper surface of the base plate 24. A pair of guide portions 23 b extending in the sub-scanning direction X is provided between the support plate 22 and the base plate 24. When the linear motor 23a operates, the support plate 22 moves in the sub scanning direction X along the guide portion 23b.

  The main scanning mechanism 25 has a linear motor 25a. The linear motor 25 a includes a mover attached to the lower surface of the base plate 24 and a stator laid on the base 106 of the pattern drawing apparatus 100. A pair of guide portions 25 b extending in the main scanning direction is provided between the base plate 24 and the base 106. When the linear motor 25 a operates, the base plate 24 moves in the main scanning direction Y along the guide portion 25 b on the base 106.

  The stage position measurement unit 30 measures the position of the stage 10. The stage position measurement unit 30 is electrically connected to the irradiation control unit 61 of the control unit 60 and measures the position of the stage 10 in accordance with an instruction from the control unit 60. The stage position measurement unit 30 irradiates laser light toward the stage 10 and measures the position of the stage 10 using interference between the reflected light and the emitted light, for example. The configuration and operation of the stage position measurement unit 30 are not limited to this. In the present embodiment, the stage position measurement unit 30 includes an emission unit 31 that emits laser light, a beam splitter 32, a beam bender 33, a first interferometer 34, and a second interferometer 35. The emission unit 31 and the interferometers 34 and 35 are electrically connected to the control unit 60, and measure the position of the stage 10 in accordance with an instruction from the control unit 60.

  The laser light emitted from the emission unit 31 enters the beam splitter 32 and is branched into first branched light that goes to the beam bender 33 and second branched light that goes to the second interferometer 35. The first branched light is used for obtaining a position parameter corresponding to the first part of the stage 10 by the first interferometer 34. The second branched light is used to obtain a position parameter corresponding to the second part of the stage 10 by the second interferometer 35 (however, the second part is a position different from the first part). Is done. The irradiation control unit 61 acquires position parameters corresponding to the positions of the first and second parts of the stage 10 from the first interferometer 34 and the second interferometer 35. Then, the position of the stage 10 is calculated based on each position parameter.

  The alignment unit 361 images the reference mark formed on the upper surface of the substrate 9. In addition to the illumination unit 362, the alignment unit 361 includes a lens barrel, an objective lens, and a CCD image sensor 364 (see FIG. 3). The CCD image sensor 364 is, for example, an area image sensor (two-dimensional image sensor).

  The illumination unit 362 is connected to the alignment unit 361 via the fiber 363, and supplies illumination light to the alignment unit 361. The light guided by the fiber 363 is guided to the upper surface of the substrate 9 through the lens barrel, and the reflected light is received by the CCD image sensor 364 shown in FIG. 3 through the objective lens. Thereby, the upper surface of the substrate 9 is imaged. The CCD image sensor 364 is electrically connected to the drawing data generation unit 62 of the control unit 60, acquires imaging data in response to an instruction from the control unit 60, and transmits the imaging data to the control unit 60. The alignment unit 361 may further include an autofocus unit capable of autofocusing.

  FIG. 4 is a diagram illustrating a configuration of the optical unit 40. The optical unit 40 includes a light source unit 41 and two optical heads 42, and is a light irradiation unit that irradiates the substrate 9 with spatially modulated light. The optical head 42 spatially modulates the laser light supplied from the light source unit 41. The light source unit 41 includes a laser driving unit 411, a laser oscillator 412 that is a light source, and an illumination optical system 413. These components are provided corresponding to each optical head 42. Laser light is emitted from the laser oscillator 412 by the operation of the laser driving unit 411 and introduced into the optical head 42 via the illumination optical system 413.

  The optical head 42 includes an incident portion 421, a spatial light modulator 422, an optical system 423, an irradiation position shift mechanism 424, and a projection optical system 425. The incident unit 421 introduces light from the light source unit 41 into the optical head 42. The spatial light modulator 422 spatially modulates the introduced light. The optical system 423 guides the light from the incident unit 421 to the spatial light modulator 422. The irradiation position shift mechanism 424 includes a pair of wedge prisms, shifts the optical axis 401 by changing the distance between the pair of wedge prisms, and relatively shifts the drawing position on the upper surface of the substrate 9 in the sub-scanning direction. Let The projection optical system 425 guides light from the irradiation position shift mechanism 424 to the upper surface of the substrate 9.

  The spatial light modulator 422 is a diffraction grating type and a reflection type, and is a diffraction grating capable of changing the depth of the grating. The spatial light modulator 422 is manufactured using a semiconductor device manufacturing technique. The diffraction grating type optical modulator used in the present embodiment is, for example, GLV (Grating Light Valve) (registered trademark of Silicon Light Machines (Sunnyvale, Calif.)). By using GLV, the amount of light irradiation can be changed in multiple steps in units of pixels in accordance with the irradiation control data given from the irradiation controller 61.

  FIG. 5 is an enlarged view of the spatial light modulator 422. In the spatial light modulator 422, the movable ribbons 51 and the fixed ribbons 52 are alternately arranged in parallel in a predetermined arrangement direction. Each ribbon 51, 52 has an elongated shape in a direction perpendicular to the arrangement direction. The movable ribbon 51 and the fixed ribbon 52 have substantially the same width and are arranged at a constant pitch. The movable ribbon 51 can move up and down relatively with respect to the reference plane behind, and the fixed ribbon 52 is fixed with respect to the reference plane.

  In the spatial light modulator 422, one grating element 5 is composed of a set of a movable ribbon 51 and a fixed ribbon 52. Therefore, the lattice elements 5 are arranged in a line in one direction corresponding to the sub-scanning direction (hereinafter referred to as “lattice arrangement direction”). In the spatial light modulator 422, for example, 8000 lattice elements 5 are arranged. The light beam cross section of the light from the optical system 423 is linear in the lattice arrangement direction and is irradiated onto the plurality of lattice elements 5.

  The upper surface of the movable ribbon 51 is a strip-like movable reflecting surface 511 that is elongated in a direction parallel to the reference plane and perpendicular to the lattice arrangement direction. The upper surface of the fixed ribbon 52 is also a strip-shaped fixed reflecting surface 521 that is elongated in a direction parallel to the reference surface and perpendicular to the lattice arrangement direction. Therefore, each lattice element 5 is essentially a combination of the fixed reflecting surface 521 and the movable reflecting surface 511. Both ends of the movable ribbon 51 are supported, and the amount of deflection of the movable ribbon 51 changes by changing the potential difference (voltage) between the movable ribbon 51 and the reference plane. That is, the movable reflective surface 511 can move in the vertical direction perpendicular to the movable reflective surface 511. Thereby, the distance between the movable reflective surface 511 and the fixed reflective surface 521 in the direction perpendicular to the reference surface changes.

  FIG. 6 is a diagram illustrating a state in which the (± 1) -order diffracted light L1 is emitted from the spatial light modulator 422. In the state where the (± 1) -order diffracted light L1 is emitted, the optical path of the light reflected by the movable reflective surface 511, that is, the optical path of the light passing through the movable reflective surface 511, and the fixed reflective surface 521 are reflected. The optical path length difference from the optical path of the light, that is, the optical path of the light passing through the fixed reflecting surface 521, is a length obtained by adding a half wavelength to an integer multiple of 0 or more of the wavelength. As a result, the light reflected by the movable reflecting surface 511 and the light reflected by the fixed reflecting surface 521 are strengthened in the diffraction direction, and zero-order diffracted light (or regular reflected light) is not emitted. For example, when it is assumed that light is incident on the spatial light modulator 422 perpendicularly, the height difference d1 between the movable reflecting surface 511 and the fixed reflecting surface 521 is ((n + 1/2) · λ / 2). The optical path length difference is ((n + 1/2) · λ). However, n is an integer greater than or equal to 0.

  Actually, since incident light is incident from a direction perpendicular to the grating arrangement direction and inclined with respect to the movable reflecting surface 511 and the fixed reflecting surface 521, the height difference between the movable reflecting surface 511 and the fixed reflecting surface 521. Is not ((n + 1/2) · λ / 2). The same applies to d2 in FIG. 7, d11 in FIG. 11, and d13 and d14 in FIG.

  FIG. 7 is a diagram illustrating a state in which the 0th-order diffracted light L2 is emitted from the left five grating elements 5. In the grating element 5 that emits the 0th-order diffracted light L <b> 2, the movable reflective surface 511 approaches the reference surface 501 due to the bending of the movable ribbon 51, and the light path that passes through the movable reflective surface 511 and the fixed reflective surface 521. The optical path length difference from the optical path of light is an integer multiple of 0 times or more of the wavelength. Thereby, the light reflected by the movable reflecting surface 511 and the light reflected by the fixed reflecting surface 521 are intensified, and the first-order diffracted light is not emitted. For example, when it is assumed that light is incident on the spatial light modulator 422 perpendicularly, the difference d2 in height between the movable reflecting surface 511 and the fixed reflecting surface 521 is (n · λ / 2), so that the optical path length difference. Becomes (n · λ). However, n is an integer greater than or equal to 0. When the spatial light modulator 422 is for i-line, the movable ribbon 51 moves by 90 nm or more. The light used for drawing is not limited to i-line.

  In the optical unit 40, the first-order diffracted light is shielded by the light shielding plate and is not guided to the substrate 9. On the other hand, the 0th-order diffracted light is guided to the substrate 9 via the irradiation position shift mechanism 424 and the projection optical system 425. In the following description, the first state of each grating element 5 when the first-order diffracted light is emitted is referred to as an “OFF state”, and the second state of each grating element 5 when the zero-order diffracted light is emitted. This is called “ON state”.

  As illustrated in FIG. 3, the control unit 60 includes an irradiation control unit 61 and a drawing data generation unit 62. The drawing data generation unit 62 generates stripe data. The stripe data is data for controlling the spatial light modulator 422 of the optical unit 40 and the stage moving mechanism 20, and is drawing data for one stripe (one swath) on the substrate 9. The stripe data is input to the irradiation control unit 61, and pattern drawing is performed by the optical head 42 of the optical unit 40 and the stage moving mechanism 20.

  The drawing data generation unit 62 is a computer having a CPU (Central Processing Unit), a storage unit 625, and the like, and is arranged in an electrical rack (not shown) together with the irradiation control unit 61. When the CPU of the drawing data generation unit 62 executes arithmetic processing according to a predetermined program, a run length data generation unit 621, a correction amount calculation unit 622, and a data correction unit 623 are realized.

  FIG. 8 is a diagram showing a preparation work by the user of the pattern drawing apparatus 100 and a flow of operations of the pattern drawing apparatus 100. When the pattern drawing apparatus 100 is operated, the design data 601 in the vector format is generated in advance by an external CAD or the like by the user. The drawing pattern indicated by the design data 601 is, for example, a pattern drawn by being superimposed on the base pattern, and the design data 601 indicates the dose of each part of the drawing pattern. The design data 601 is input to the drawing data generation unit 62 and stored in the storage unit 625.

  When the design data 601 is prepared, the design data 601 is rasterized by the run length data generation unit 621, and run length data 602 that is raster data is generated (step S11). The run length data 602 is stored in the storage unit 625. Usually, in the rasterizing process, run-length data 602 having a pixel value of “0” or “1” is generated. The pattern drawing apparatus 100 can also generate run-length data whose pixel value is “0”, “0.5”, or “1” when a high resolution of the drawing position is required. The user designates which format of data is to be generated before rasterization. Specifically, information indicating the number of gradations of the pixel value after rasterization is given to the attribute of the design data 601 that is vector data.

  Each pixel value of the pixels arranged in the direction corresponding to the sub-scanning direction is an instruction value that indicates the amount of movement of the movable ribbon 51 of the lattice element 5. The pixel value can be set to another value. That is, the gradation of each lattice element 5 is controlled by the pixel value.

  If there is a pixel with the pixel value “0.5”, the run-length data generation unit 621 changes the pixel value of the pixel with the pixel value “1” adjacent to the pixel in the sub-scanning direction. Details of the processing will be described later.

  When the run-length data 602 is generated, or in parallel with the generation of the run-length data 602, the unprocessed substrate 9 stored in the cassette 90 is unloaded by the transfer device 110 and placed on the stage 10. (Step S12). Then, the stage moving mechanism 20 is controlled based on the design position information of the reference mark (alignment mark) given from the drawing data generation unit 62, and any one of the reference marks on the substrate 9 becomes the CCD image sensor 364 of the alignment unit 361. Move directly below. The CCD image sensor 364 images the reference mark.

  The image signal output from the CCD image sensor 364 is processed by an image processing circuit in the electrical equipment rack, and the position of the reference mark on the stage 10 is accurately obtained (step S13). The above operation is performed for each of the plurality of reference marks on the substrate 9. When the measurement position information of all the reference marks is obtained, the rotation mechanism 21 is controlled to slightly rotate the stage 10 around the vertical axis so that the substrate 9 is aligned (positioned) in a direction suitable for pattern drawing on the substrate 9. (Step S14). The alignment may be performed after the stage 10 is moved to a position directly below the optical head 42.

  The correction amount calculation unit 622 acquires the measurement position information of the reference mark and the correction amount of the orientation of the substrate 9, and obtains the position of the reference mark after alignment. Further, the positional deviation of the reference mark with respect to the background pattern of the drawing pattern described by the design data 601 is obtained, and the drawing pattern correction amount for eliminating the positional deviation is calculated.

  The data correction unit 623 reads the run length data in block units, that is, in block run length data units corresponding to a part of one stripe, and performs correction based on the correction amount for each block run length data (step S15). In the correction of block run length data, a process is performed in which the pixel value of each pixel is shifted in at least one of the main scanning direction and the sub-scanning direction in units of pixels. At this time, the pixel value of the pixel of the adjacent block run length data is referred to as appropriate.

  The data correction unit 623 concatenates the corrected block run length data arranged in the main scanning direction, and generates stripe data corresponding to one stripe. The stripe data is output to the irradiation control unit 61, and the irradiation control unit 61 controls the optical head 42 and the stage moving mechanism 20 according to the stripe data.

  Specifically, the main scanning mechanism 25 starts the movement of the substrate 9 in the main scanning direction parallel to the main surface, and from the two optical heads 42 in parallel with the relative movement of the substrate 9 with respect to the optical unit 40. Irradiation of the spatially modulated light onto the substrate 9 starts from the beginning of a region corresponding to two stripes (hereinafter referred to as “striped region”). Thereby, pattern drawing is started. In the spatial light modulator 422, the pixel value is converted into a potential difference between the movable ribbon 51 and the reference plane, and the movable ribbon 51 moves toward the reference plane by an amount corresponding to the pixel value. Therefore, by taking multi-tone values other than “0” and “1”, the intensity of light emitted from the lattice element 5 to the substrate 9 is variously changed.

  When drawing to the end of the stripe region is performed (step S16), the emission of light from the optical head 42 is temporarily stopped, and the movement of the substrate 9 in the main scanning direction is also stopped. Moves in the sub-scanning direction perpendicular to the main scanning direction and parallel to the main surface of the substrate 9 by the width of the stripe region. Then, drawing on the two stripe regions is performed by the two optical heads 42 while the substrate 9 moves in the opposite direction to the previous main scanning. When the movement of the substrate 9 in the sub-scanning direction and the movement in the main scanning direction is repeated and drawing of all the stripes is completed (step S17), the substrate 9 is unloaded by the transport device 110 and stored in the cassette 90 (step S17). S18). Each optical head 42 is responsible for drawing half of the substrate 9.

  FIG. 9 is a diagram illustrating a part of the run-length data generated in step S11. The vertical direction in FIG. 9 corresponds to the main scanning direction, and the horizontal direction corresponds to the sub-scanning direction, that is, the lattice arrangement direction. Two broken lines 721 indicate lines in the vector data, and an area between the two broken lines 721 is an area to be drawn. The vector data is data in which a value is assigned to each pixel by rasterization. Pixels 722 that are not given parallel diagonal lines indicate positions on the substrate 9 where no light is irradiated, and are given a pixel value “0”. Pixels 723 with parallel diagonal lines indicate positions where light is irradiated on the substrate 9 and are given a pixel value “1”. That is, when one grid element 5 is located on the substrate 9 at a position corresponding to the pixel 722, the grid element 5 is turned off, and when it is located at a position corresponding to the pixel 723, the grid element 5 is turned on.

  FIG. 9 shows an example when the user designates the pixel value to be either “0” or “1” during rasterization. On the other hand, when the user designates the pixel value to be any one of “0”, “0.5”, and “1”, the data immediately after the rasterization is as shown in FIG. However, FIG. 10 shows a state before the pixel value correction described later by the run-length data generation unit 621 is performed. In FIG. 10, a pixel 722 without parallel diagonal lines indicates a position on the substrate 9 where no light is irradiated, and a pixel value “0” is given. Pixels 723 with dense parallel diagonal lines indicate positions where light is irradiated on the substrate 9 and are given a pixel value “1”. A pixel 724 with a rough parallel oblique line indicates a position on the substrate 9 where light having about half the intensity of the pixel 722 is irradiated, and a pixel value “0.5” is given. In the pixel having the pixel value “0.5”, the area to be drawn indicated by the vector data is, for example, 1/3 or more and less than 2/3 (or greater than 1/3 and 2/3 or less).

  FIG. 11 is a diagram showing a simplified display of the lattice element 5 in the ON state and the lattice element 5 in the OFF state. In the following description, the lattice element 5 is simply displayed, and in the ON state, the movable reflective surface 511 and the fixed reflective surface 521 are shown at the same height, and in the OFF state, the movable reflective surface 511 and the fixed reflective surface are shown. The height difference d11 from 521 is shown as being ¼ of the wavelength. That is, in the ON state, the optical path length difference between the optical path of the light passing through the movable reflecting surface 511 and the optical path of the light passing through the fixed reflecting surface 521 is 0, and in the OFF state, the optical path length difference is 1 of the wavelength. / 2.

  FIG. 12 is a diagram showing a state of the lattice element 5 corresponding to the position 731 in FIG. 9 in a simple display. In the pixels lined up in the sub-scanning direction at the position 731, the pixel values of the eight pixels are “1”, and the pixel values of the other pixels are “0”. Correspondingly, in FIG. 12, eight lattice elements 5 are in the ON state, and the other lattice elements 5 are in the OFF state.

  FIG. 13 is a diagram showing a state of the lattice element 5 corresponding to the position 732 in FIG. However, a state before correction of a pixel value described later is shown. In FIG. 10, the pixel values of the seven pixels are “1”, the pixel values of the pixels adjacent to both sides of these pixels are “0.5”, and the pixel values of the other pixels are “0”. is there. Correspondingly, in FIG. 13, seven lattice elements 5 are in the ON state, and the lattice elements 5 adjacent to these lattice elements 5 are in the third state between the OFF state and the ON state (hereinafter referred to as “ON state”). , Referred to as “intermediate state”), and the other lattice elements 5 are in the OFF state.

  As shown on the left side of FIG. 14, in the intermediate state, the height difference d13 between the movable reflecting surface 511 and the fixed reflecting surface 521 is 1/8 of the wavelength. That is, the optical path length difference between the optical path of light passing through the movable reflective surface 511 in the ON state and the optical path of light passing through the movable reflective surface 511 in the intermediate state is ¼ of the wavelength. As a result, a region on the substrate 9 corresponding to the lattice element 5 in the intermediate state is theoretically irradiated with light having half the intensity of the ON state. As a result, on the substrate 9, the boundary of the photosensitive region is located on the region corresponding to the lattice element 5 in the intermediate state. That is, the boundary of the photosensitive region is located between the region corresponding to the lattice element 5 in the ON state and the region corresponding to the lattice element 5 in the OFF state.

  FIG. 15 is a diagram showing a state of the actual lattice element 5 corresponding to the position 732 in FIG. That is, a state after the pixel value is corrected by the run length data generation unit 621 is shown. In the case of FIG. 15, the pixel value of one pixel is “1”, the pixel values of three adjacent pixels on both sides of this pixel are larger than “0.5”, and more than “1”. The pixel values of the pixels adjacent to these pixels are “0.5”, and the pixel values of the other pixels are “0”. Correspondingly, one lattice element 5 is in an ON state, and three lattice elements 5 adjacent to each side of the lattice element 5 are in a fourth state (hereinafter, referred to as an intermediate state) and an ON state. The grid elements 5 adjacent to these grid elements 5 are in an intermediate state, and the other grid elements 5 are in an OFF state.

  As shown on the right side of FIG. 14, in the incomplete ON state, the height difference d14 between the movable reflecting surface 511 and the fixed reflecting surface 521 is 1/12 of the wavelength. That is, the difference in optical path length between the optical path of light passing through the movable reflecting surface 511 in the ON state and the optical path of light passing through the movable reflecting surface 511 in the incomplete ON state is 1/6 of the wavelength. .

  In the pattern drawing apparatus 100, the pixel value in the raster data functions as an instruction value indicating the state of each lattice element 5, and as shown in FIGS. 11 and 14, the lattice element 5 is in an OFF state, an ON state, It is possible to enter an intermediate state and an incomplete ON state. In the drawing data generation unit 62, the pixel value “0” that indicates the OFF state to the lattice element 5 in the pixel values that are the plurality of instruction values respectively associated with the plurality of lattice elements 5 in the data immediately after the rasterization. When the pixel value “0.5” indicating the intermediate state to the lattice element 5 and the pixel value “1” indicating the ON state to the lattice element 5 are arranged in this order, the run-length data generation unit 621 The pixel value indicating at least one ON state continuous with the pixel value indicating the intermediate state is changed to a pixel value indicating the incomplete ON state.

  In other words, when the lattice elements 5 scheduled to be in the OFF state, the intermediate state, and the ON state are arranged in this order corresponding to the direction intersecting the edge of the pattern to be drawn, the intermediate state is continuously from the lattice element 5. At least a part of the lattice elements 5 that should be in the ON state is set to the incomplete ON state, and the lattice elements 5 in the OFF state, the intermediate state, and the incomplete ON state are arranged in this order. This suppresses a decrease in the allowable range of the position of the drawing surface in the optical axis direction (hereinafter referred to as “the height of the drawing surface”). Hereinafter, the fact that such an effect can be obtained in the pattern drawing apparatus 100 will be described in detail.

  FIG. 16 is a diagram showing how the depth of focus becomes narrower when the lattice element 5 in the intermediate state exists, and the allowable range of the height of the drawing surface decreases. In the graph of FIG. 16, the horizontal axis indicates the amount of deviation in the optical axis direction from the position in the optical axis direction of the designed drawing surface (hereinafter referred to as “drawing reference height”), and the vertical axis indicates a line width of 10 μm. The result of calculating the line width of a pattern actually drawn when a plurality of linear patterns extending in the main scanning direction are drawn side by side in the sub-scanning direction is shown. The distance between the lines is also 10 μm, and a so-called 10 μm line and space is drawn. The larger the value on the horizontal axis, the farther the drawing surface is from the optical head 42. Here, it is assumed that (± 0.3) μm is the allowable range of the line width. The pixel pitch in the sub-scanning direction on the drawing surface is 1 μm.

  Reference numeral 801 indicates a line width obtained when the lattice element 5 is controlled only in either the ON state or the OFF state, as shown in FIG. In this case, a pattern having a line width within an allowable range is drawn within a range of (± 50) μm from the drawing reference height. That is, at least the entire range shown on the horizontal axis is the allowable range of the height of the drawing surface.

  Reference numeral 810 indicates a line width obtained when the lattice elements 5 in the OFF state, the intermediate state, and the ON state are arranged in this order as shown in FIG. In this case, in order to obtain a pattern having a line width within an allowable range, a deviation of (± 12.5) μm from the drawing reference height is allowed. That is, the allowable range is 25 μm, and the substrate 9 is allowed to fluctuate only up and down (± 12.5) μm during drawing. Thus, when drawing is performed with high position resolution using the intermediate state, the allowable range of the height of the drawing surface is greatly reduced.

  Reference numeral 812 indicates a case where two ON-state lattice elements 5 adjacent to the intermediate-state lattice element 5 are changed to an incomplete ON state, and reference numeral 813 indicates an intermediate-state lattice element 5 as shown in FIG. 3 shows a case where three ON-state lattice elements 5 adjacent to are changed to an incomplete ON state, and reference numeral 819 denotes a case where all the ON-state lattice elements 5 are changed to an incomplete ON state. As shown by reference numerals 812, 813 and 819, it can be seen that in any case, the allowable range of the height of the drawing surface is wider than that of the reference numeral 810 which does not provide the incomplete ON state. In particular, in the case of reference numeral 813, the allowable range is the widest.

  FIG. 17 is a diagram showing the light intensity distribution in the sub-scanning direction at the position in the regular reflection direction in the spatial light modulator 422 when three consecutive ON states and three consecutive intermediate states are alternately set. is there. Reference numeral 821 indicates the intensity distribution at the drawing reference height, and reference numerals 822, 823, 824, 825, 826, and 827 denote (+10) μm from the drawing reference height toward the direction away from the optical head 42. , (+20) μm, (+30) μm, (−10) μm, (−20) μm, and (−30) μm show the intensity distribution at the height.

  As shown in FIG. 17, when the lattice element 5 in the ON state and the lattice element 5 in the OFF state coexist, the intensity distribution changes asymmetrically when approaching or separating from the optical head 42. Thus, the light from the lattice element 5 in the intermediate state has a great influence on the light from the lattice element 5 in the ON state. Also in FIG. 16, the light from the lattice element 5 in the ON state is affected by the light from the lattice element 5 in the ON state, and as indicated by reference numerals 801 and 810, only the ON state and the OFF state are The allowable range of the height of the drawing surface differs greatly depending on whether the state exists.

  On the other hand, as indicated by reference numerals 812, 813, and 819, it has been found by simulation that the allowable range is widened when the lattice element 5 in the incomplete ON state is adjacent to the lattice element 5 in the intermediate state. By utilizing this phenomenon, a decrease in the allowable range of vertical movement during transport of the substrate 9 is suppressed.

  FIG. 18 is a diagram corresponding to FIG. 16 when a plurality of linear patterns having a line width of 20 μm extending in the main scanning direction are drawn in a line and space of 20 μm, and FIG. 19 is a diagram having a line width of 30 μm. FIG. 17 is a diagram corresponding to FIG. 16 in a case where a plurality of linear patterns extending in the main scanning direction are drawn with a line and space of 30 μm. The horizontal axis indicates the amount of deviation from the drawing reference height, and the vertical axis indicates the line width of the pattern that is actually drawn. The allowable range of the line width is (± 0.3) μm. Also in these simulations, the pixel pitch in the sub-scanning direction on the drawing surface is 1 μm.

  In FIG. 18, reference numeral 830 indicates the line width obtained when the grid elements 5 in the OFF state, the intermediate state, and the ON state are arranged in this order on both sides of the drawn line. When the line width is 20 μm, the lattice elements 5 in the intermediate state are located on both sides of the 19 lattice elements 5 in the ON state. Reference numerals 831, 832, 833, 834, and 835 respectively indicate one, two, three, four, and five incompletely ON state lattice elements 5 following the OFF state and intermediate state lattice elements 5. Are arranged, and the lattice elements 5 in the ON state are arranged. Reference numeral 839 indicates a case where all the lattice elements 5 between the pair of lattice elements 5 in the intermediate state are in an incompletely ON state. From these graphs, it can be seen that when the number of lattice elements 5 in the incomplete ON state is 3, the maximum allowable range of the height of the drawing surface is wide.

  In FIG. 19, reference numeral 840 indicates a line width obtained when the grid elements 5 in the OFF state, the intermediate state, and the ON state are arranged in this order on both sides of the drawn line. When the line width is 30 μm, the lattice elements 5 in the intermediate state are positioned on both sides of the 29 lattice elements 5 in the ON state. Reference numerals 841, 842, 843, 844, 845, and 846 indicate one, two, three, four, five, and six incomplete ONs following the lattice element 5 in the OFF state and the intermediate state, respectively. In this example, the lattice elements 5 in the state are arranged, and the lattice elements 5 in the ON state are arranged. Also from these graphs, it can be seen that when the number of lattice elements 5 in an incompletely ON state is 3, the allowable range of the height of the drawing surface is the widest.

  From FIG. 16, FIG. 18 and FIG. 19, in general, the number of grid elements 5 in an incomplete ON state following grid elements 5 in an OFF state and an intermediate state, that is, incomplete from the pixel value indicating the ON state at the time of rasterization. It can be said that the number of pixels to be changed to the pixel value indicating the ON state is preferably 3. For example, as shown in FIG. 12, when N ON-state lattice elements 5 are continuously present between the OFF-state lattice elements 5, the line to be drawn is arranged at the pitch of the lattice elements 5 in the sub-scanning direction. When the line is shifted by half (that is, the pitch of the pixel) or a line shifted by half the pitch is drawn, as shown in FIG. 13, one ON-state lattice element 5a located at the end moves to the intermediate state. As a result, the one off-state lattice element 5b on the opposite side is changed to the intermediate state. At this stage, the number of lattice elements 5 in the ON state is (N−1). Therefore, as shown in FIG. 15, when three incompletely-ON lattice elements 5 are set on both sides, the number of ON-state lattice elements 5 is (N-7) in the center.

  Next, as a result of examining how it is most preferable to set the height of the movable reflecting surface 511 when the number of incompletely ON state lattice elements 5 adjacent to the intermediate state lattice element 5 is three. explain.

  FIG. 20 is a diagram showing the relationship between the amount of deviation from the drawing reference height and the line width when a plurality of lines extending in the main scanning direction are drawn with a line and space of 10 μm. Reference numeral 852 indicates that the difference between the optical path length of the light passing through the movable reflecting surface 511 of the grating element 5 in the ON state and the optical path length of the light passing through the movable reflecting surface 511 of the grating element 5 in the incomplete ON state is In this case, the phase difference is equal to 20 ° with respect to the wavelength of. Reference numerals 853, 854, 855, 856, 857, 858, and 859 denote cases where the optical path length differences are 30 °, 40 °, 50 °, 60 °, 70 °, 80 °, and 90 °, respectively. . Since the phase difference of 90 ° is ¼ of the wavelength, in this case, three intermediate state lattice elements 5 are arranged in succession to the intermediate state lattice element 5.

  FIG. 21 shows a case where a 20 μm line and space is drawn by a plurality of lines extending in the main scanning direction. Reference numerals 862, 863,..., 869 denote optical path length differences of light passing through the movable reflecting surface 511 between the ON state and the incomplete ON state, respectively, with phase differences of 20 °, 30 °,. A case of 90 ° is shown. FIG. 22 shows a case where a 30 μm line and space is drawn by a plurality of lines extending in the main scanning direction. Reference numerals 872, 873,... 879 indicate that the optical path length difference is 20 °, 30 °,. . . , 90 ° is shown.

  20 to 22, generally, the smaller the inclination of each graph at the drawing reference height, the wider the allowable range of the drawing surface height. FIG. 23 is a diagram illustrating a relationship between the phase difference and the inclination of each graph. Reference numerals 881, 882 and 883 correspond to FIGS. 20 to 22, that is, line and space of 10 μm, 20 μm and 30 μm, respectively. In any graph, the phase difference is 60 ° and the inclination is almost zero. From this, it can be seen that the optical path length difference of the optical path passing through the movable reflecting surface 511 between the incomplete ON state and the ON state is preferably 1/6 of the wavelength. In theory, 75% of the light in the ON state is emitted in the regular reflection direction from such an incomplete ON state.

  In the pattern drawing apparatus 100, when the lattice elements 5 in the OFF state, the intermediate state, and the ON state are arranged in this order based on the above examination results, the three lattice elements 5 continuous to the lattice element 5 in the intermediate state are incomplete. Changed to ON state. Actually, after raster data having only pixel values “0”, “0.5”, and “1” is generated from the vector data in step S11, sub-scanning is performed from the pixel having the pixel value “0.5”. The pixel values of the three pixels having the pixel value “1” aligned in the direction are changed to “0.67”, for example.

  It is preferable that the pixel value indicating the incomplete ON state is accurately determined by measuring the relationship between the voltage and the deflection amount of the movable reflecting surface 511. When the number of pixels having the pixel value “1” is 6 or less between the pair of pixels having the pixel value “0.5”, the pixels of all the pixels having the pixel value “1” are incompletely ON. Changed to a value.

  Although the embodiment of the present invention has been described above, the present invention is not limited to the above embodiment, and various modifications can be made.

  The optical path length difference of the optical path passing through the movable reflecting surface 511 between the intermediate state and the ON state may be other than ¼ of the wavelength as long as it is between the ON state and the OFF state. By setting the optical path length difference to ¼ of the wavelength, the intensity of the light emitted from the lattice element 5 in the intermediate state becomes 0.5 times that in the ON state, and the process at the time of rasterization becomes simple.

  The number of pixels to be changed from the pixel value indicating the ON state to the pixel value indicating the incomplete ON state may be at least one, and all the pixel values between the pair of intermediate values indicating the intermediate state The pixel value indicating the ON state may be changed to a pixel value indicating the incomplete ON state. Immediately after rasterization, the pixel value indicating the intermediate state may be set only on one side of the pixel row of the pixel value indicating the ON state. In this case, the pixel value indicating the ON state is changed to the pixel value indicating the incomplete ON state only on one side of the pixel row instructing the ON state.

  Between the incomplete ON state and the ON state, the optical path length difference of the light path passing through the movable reflecting surface 511 may not be strictly 1/6 of the wavelength. If it is substantially 1/6 of the wavelength, a high effect can be obtained.

  The pixel value indicating the incomplete ON state may not be only one value. For example, the pixel value indicating the first incomplete ON state between the ON state and the intermediate state, and the pixel value indicating the second incomplete ON state between the ON state and the first incomplete ON state are intermediate. It may be arranged continuously from pixel values indicating the state.

  In the above embodiment, a pixel value that indicates an intermediate state may be used for a fine shift of the drawing position with respect to the background. Such a shift of the drawing position may be performed only in a part of the arrangement of the lattice elements 5 of the spatial light modulator 422.

  In the above-described embodiment, the position resolution in the sub-scanning direction can be improved by setting the lattice element 5 in the intermediate state. However, in the main scanning direction, the moving speed of the substrate 9 is decreased, the drawing timing is shifted, etc. The position resolution may be improved by various methods.

  The moving direction of the substrate 9 with respect to the optical unit 40 may not be perpendicular to the lattice arrangement direction. That is, the relative movement direction of the substrate 9 with respect to the optical unit 40 may be a direction that intersects the direction on the substrate 9 corresponding to the lattice arrangement direction. Further, the position of the substrate 9 may be fixed and the optical unit 40 may move. The position of the substrate 9 may be fixed with respect to one of the main scanning direction or the sub-scanning direction, and the position of the optical unit 40 may be fixed with respect to the other. Thus, the mechanism which moves the board | substrate 9 relatively with respect to the optical unit 40 which is a light irradiation part can be provided in various aspects.

  In the spatial light modulator 422, in the grating element 5, the movable reflective surface 511 and the fixed reflective surface 521 may be positioned at the same height in the ON state. In the OFF state, the fixed reflecting surface 521 may be positioned higher than the movable reflecting surface 511 from the reference surface.

  The configurations in the above embodiment and each modification may be combined as appropriate as long as they do not contradict each other.

DESCRIPTION OF SYMBOLS 5 Grating element 9 Substrate 10 Stage 20 Stage moving mechanism 40 Optical unit 62 Drawing data generation part 100 Pattern drawing apparatus 412 Laser oscillator 422 Spatial light modulator 511 Movable reflecting surface 521 Fixed reflecting surface S11-S18 Step

Claims (10)

A pattern drawing device,
A support for supporting the substrate;
A light irradiation unit for irradiating the substrate with spatially modulated light;
A moving mechanism for moving the substrate relative to the light irradiation unit;
A drawing data generation unit for generating data for controlling the light irradiation unit and the moving mechanism;
With
The light irradiator is
A light source;
A diffraction grating-type and reflection-type spatial light modulator in which a plurality of grating elements are arranged in a line;
With
A relative movement direction of the substrate by the moving mechanism is a direction intersecting a direction on the substrate corresponding to an arrangement direction of the plurality of lattice elements;
Each of the plurality of lattice elements is a combination of one fixed reflective surface and one movable reflective surface extending in a direction perpendicular to the arrangement direction, and the movable reflective surface is in a direction perpendicular to the movable reflective surface. Is movable,
Each of the plurality of grating elements has an optical path length difference between an optical path passing through the movable reflecting surface and an optical path passing through the fixed reflecting surface plus a half wavelength added to an integer multiple of 0 or more times the wavelength of the light. A first state, a second state in which the optical path length difference is the integer multiple of the wavelength of the light, a third state between the second state and the first state, and Can be a fourth state between a third state and the second state;
The drawing data generation unit instructs the lattice element to indicate an instruction value for instructing the first state to the lattice element and a plurality of instruction values respectively associated with the plurality of lattice elements. When the instruction value and the instruction value for instructing the second element to the lattice element are arranged in this order, the at least one second state is instructed following the instruction value for instructing the third state. A pattern drawing apparatus, wherein an instruction value is changed to an instruction value indicating the fourth state. The pattern drawing apparatus according to claim 1,
The pattern drawing apparatus, wherein an optical path length difference of an optical path passing through the movable reflecting surface between the third state and the second state is ¼ of the wavelength. The pattern drawing apparatus according to claim 2,
A pattern drawing apparatus that changes instruction values for instructing the second state, which are three consecutive to the instruction value for instructing the third state, to instruction values for instructing the fourth state. It is a pattern drawing apparatus of Claim 3, Comprising:
The pattern drawing apparatus, wherein an optical path length difference of an optical path passing through the movable reflecting surface between the fourth state and the second state is 1/6 of the wavelength. The pattern drawing apparatus according to any one of claims 1 to 4,
A pattern drawing apparatus, wherein the substrate is a semiconductor substrate. A pattern drawing method,
a) moving the substrate relative to the light irradiation unit;
b) irradiating the substrate with spatially modulated light from the light irradiating unit in parallel with the step a);
With
The light irradiator is
A light source;
A diffraction grating-type and reflection-type spatial light modulator in which a plurality of grating elements are arranged in a line;
With
A relative movement direction of the substrate with respect to the light irradiation unit is a direction intersecting a direction on the substrate corresponding to an arrangement direction of the plurality of lattice elements;
Each of the plurality of lattice elements is a combination of one fixed reflective surface and one movable reflective surface extending in a direction perpendicular to the arrangement direction, and the movable reflective surface is in a direction perpendicular to the movable reflective surface. Is movable,
Each of the plurality of grating elements has an optical path length difference between an optical path passing through the movable reflecting surface and an optical path passing through the fixed reflecting surface plus a half wavelength added to an integer multiple of 0 or more times the wavelength of the light. A first state, a second state in which the optical path length difference is the integer multiple of the wavelength of the light, a third state between the second state and the first state, and Can be a fourth state between a third state and the second state;
In the step b), the pattern drawing method characterized in that the lattice element in the first state, the lattice element in the third state, and the lattice element in the fourth state are arranged in this order. The pattern drawing method according to claim 6,
The pattern drawing method, wherein a difference in optical path length of an optical path passing through the movable reflecting surface between the third state and the second state is ¼ of the wavelength. The pattern drawing method according to claim 7,
The pattern drawing method, wherein the three lattice elements in the fourth state are arranged in succession. The pattern drawing method according to claim 8,
The pattern drawing method, wherein a difference in optical path length of an optical path passing through the movable reflecting surface between the fourth state and the second state is 1/6 of the wavelength. The pattern drawing method according to any one of claims 6 to 9,
A pattern drawing method, wherein the substrate is a semiconductor substrate.

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