JP4801931B2 - Drawing device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To form a fine pattern precisely in drawing processing by raster scan using a light modulation unit. <P>SOLUTION: In a situation where an exposure area EA is irradiated with light of substantially constant intensity distribution, overlap exposure is performed according to continuous movement system and raster scanning. A DMD is arranged such that the exposure area EA inclines by a predetermined angle &alpha; against the feeding direction. The angle &alpha; is determined such that the diagonal line of the exposure area EA becomes parallel with the main scanning direction (X direction) and the exposure area EA is moved by a distance RH equal to one half of scanning band width RB along the feeding direction. <P>COPYRIGHT: (C)2007,JPO&amp;INPIT

Description

  The present invention relates to a drawing apparatus that forms a pattern such as a circuit pattern directly on a drawing object such as a photomask (reticle) serving as an original plate or directly a printed board or a silicon wafer. In particular, the present invention relates to drawing processing by a light modulation unit in which light modulation elements such as DMD (Digital Micro-mirror Device) and LCD are two-dimensionally arranged.

  In a drawing apparatus, a drawing process is performed on a drawing object coated with a photosensitive material such as a photoresist, and a pattern is formed on the drawing object such as a substrate through processes such as development processing, etching or plating, and resist peeling. Is done. In the case of an exposure method using a light modulation unit in which light modulation elements such as LCD, DMD, and SLM (Spatial Light Modulators) are arranged in a matrix, an irradiation spot (hereinafter referred to as an exposure area) by the light modulation unit is formed on the substrate. Scanning is performed, and each light modulation element is ON / OFF controlled at a predetermined timing in accordance with the drawing pattern. In a raster scanning drawing apparatus, the exposure areas move relative to each other sequentially in accordance with a scanning band defined along the main scanning direction.

In order to form a fine pattern, there is a drawing method in which the scanning direction is inclined relative to the arrangement direction of the light modulation elements by a predetermined angle and the exposure operation is performed while overlapping the exposure area along the main scanning direction. Known (see Patent Document 1 and Patent Document 2). Multiple exposure operations are performed before passing through the section corresponding to the irradiation area (micro spot) of one micro mirror, and the micro spots overlap each other by irradiating light on the same area It is exposed with. As a result, when a conductor pattern extending in an oblique direction is formed, the pattern can be formed with a resolution smaller than the size of the minute spot. In addition, in order to align the pattern width accurately, it is necessary to make the exposure amount uniform. When the light intensity distribution is a Gaussian distribution along the sub-scanning direction, the exposure areas should be overlapped along the sub-scanning direction. Thus, the exposure amount in the sub-scanning direction is made uniform (see Patent Document 3).
JP 2003-84444 A Special table 2004-514280 gazette JP 2004-146789 A

  Since the exposure area is inclined with respect to the sub-scanning direction, the pattern of the joint portion is formed while partially overlapping the adjacent exposure areas. When the light intensity distribution in the exposure area is uniform over the entire surface, the exposure amount in the joint portion is different from the exposure amount in the other portions, and the entire drawing surface cannot be irradiated with light uniformly. As a result, the line width of the pattern formed along the sub-scanning direction is not uniform in the resist processing, and the pattern cannot be formed with high accuracy.

  The drawing apparatus of the present invention is a drawing apparatus capable of forming a pattern such as a circuit pattern on an object to be drawn on which a photosensitive material such as a substrate is formed, and can form a pattern with high resolution by overlap exposure and drawing. It is an apparatus that can make the exposure amount of the entire surface uniform. The drawing apparatus includes a light source, a plurality of light modulation elements arranged in a matrix, a light modulation unit that irradiates the drawing object with light from the light source, and an irradiation spot (hereinafter referred to as an exposure area) by the light modulation unit. Scanning means for raster-scanning the drawing body and exposure control means for controlling a plurality of light modulation elements so as to form a pattern according to the relative position of the exposure area on the drawing body.

  The light modulation element is an element that modulates light so that light from a light source is selectively guided to a drawing object. For example, the light modulation element selectively transmits and blocks light, or selectively transmits light to the drawing object. / It is configured to guide in the retracting direction. As the light modulation unit, for example, DMD, LCD or the like is applied. The light reflected by the light modulation unit may be irradiated to a predetermined region of the drawing object via an optical system such as an illumination optical system or an imaging optical system, or may be directly irradiated without passing through the optical system. May be. Although the shape of the exposure area is defined according to the arrangement of the light modulation elements, it is rectangular, for example. The light intensity distribution in the exposure area is configured to be substantially uniform or substantially uniform. For example, an optical system or a light source is prepared so as to make the light intensity distribution uniform.

  The scanning means sequentially scans the exposure area along the main scanning direction, and when the scanning of one scanning band is completed, moves the exposure area along the sub-scanning direction to scan the next scanning band. For example, raster scanning by a continuous movement method may be executed. In this case, the exposure area moves the entire object to be drawn while reciprocating along the main scanning direction. The scanning unit may move the stage on which the drawing object is placed, or may move the light modulation unit relative to the drawing object. The exposure control means selectively controls the light modulation elements independently so that, for example, the posture of irradiating the object to be drawn or the posture of guiding the light to the other position.

  The drawing apparatus of the present invention performs an overlap exposure operation along the main scanning direction, and scans while overlapping the exposure area along the sub-scanning direction. In other words, the exposure control means executes the exposure operation while overlapping the exposure areas along the main scanning direction. In other words, the exposure operation is performed a plurality of times while the exposure area moves relative to the section length corresponding to the minute spot of the light modulation element, and the minute spots are exposed while partially overlapping each other.

  On the other hand, the scanning unit relatively moves the exposure area along the sub-scanning direction so that the exposure areas overlap along the sub-scanning direction. Further, in order to make it possible to form a fine pattern in an oblique direction, the irradiation region of the entire light modulation unit is configured to be inclined along the sub-scanning direction (or main scanning direction). Here, the entire irradiation area indicates a light irradiation area when all the light modulation elements of the light modulation unit are in a reflection state. When the exposure area and the entire irradiation area coincide with each other, the exposure area is rectangular. For example, the arrangement of the light modulation unit may be inclined with respect to the moving direction of the stage.

  In the present invention, the scanning means sets the exposure area along the sub-scanning direction by a predetermined amount so that the cumulative exposure amount becomes equal along the sub-scanning direction in the overlap zone (overlap region) between adjacent exposure areas. Only move relative. Here, the cumulative exposure amount indicates the exposure amount cumulatively accumulated while continuing the overlap exposure along the main scanning direction. As a result of the drawing process by such a drawing apparatus, the cumulative exposure amount is made uniform over the entire drawing surface, and a pattern is formed with high accuracy.

  When the exposure area is relatively moved in order along the main scanning direction in accordance with the raster scanning, a time difference occurs in the exposure timing in the vicinity of the boundary line (joint portion) between adjacent scanning bands. Therefore, a chemical reaction of a photosensitive material such as a photoresist affects the removal of the resist at the joint portion, and the line width of the pattern along the sub-scanning direction differs between the joint portion and the other portions. For this reason, the exposure area may be relatively moved along the sub-scanning direction so as to make all overlap areas in the sub-scanning direction of the drawing surface. When the exposure area is rectangular, the exposure area may be inclined with respect to the sub-scanning direction so that the diagonal lines of the exposure area are parallel along the main scanning direction. What is necessary is just to prepare the optical system defined in such a state.

  A drawing apparatus having another feature of the present invention includes a light source, a light modulation unit in which a plurality of light modulation elements are arranged in a matrix, and irradiating the object to be drawn with light from the light source, and an irradiation spot by the light modulation unit. Scanning means for raster-scanning the object to be drawn with an exposure area having a substantially uniform light intensity distribution, and a plurality of light modulation elements so as to form a pattern according to the relative position of the exposure area on the object to be drawn. Exposure control means for controlling. The exposure control means executes the exposure operation while overlapping the exposure areas along the main scanning direction, and the scanning means sub-scans the exposure areas so that the exposure areas overlap along the sub-scanning direction. Move relative to the direction.

  In the present invention, the area used for the exposure of the light modulation element of the light modulation unit is limited so that the outline of the exposure area is inclined, and the cumulative exposure amount is reduced in the overlap zone between adjacent exposure areas. The effective exposure area of the light modulation unit is defined according to the amount of relative movement along the sub-scanning direction of the exposure area so as to be equal along the scanning direction. The effective exposure area is defined by the arrangement of light modulation elements that are not used during exposure. Light modulation elements that are not used are collected in the area, and other areas are defined as effective exposure areas, or light modulation elements that are not used are optional. In this case, a portion obtained by removing the dispersed light modulation elements from all the light modulation elements of the light modulation unit is defined as an effective area. Then, the light modulation element in the effective exposure region is controlled. For example, when controlling a light modulation element according to raster data based on pattern data sent from a workstation or the like, control is performed so that a light modulation element in an area other than the effective exposure area (non-exposure area) is not executed. Therefore, the exposure area is an area narrower than the irradiation area of the entire light modulation unit, and has an arbitrary shape other than a rectangular shape. The irradiation area of the entire light modulation unit may be orthogonal along the sub-scanning direction, but the irradiation area of the effective exposure area may be inclined along the sub-scanning direction.

  The exposure control means defines the effective exposure area so that the area bisector of the exposure area is parallel to the main scanning direction and the exposure area is line symmetric or rotationally symmetric with respect to the area bisector. do it. Then, in order to make all overlap areas along the sub-scanning direction, the scanning means sets the exposure area in the sub-scanning direction by the length along the sub-scanning direction of the exposure area with the area bisector as a reference. What is necessary is just to move relatively along. For example, the exposure control means defines the effective exposure area as one of an isosceles triangle, a parallelogram, and a rhombus.

  In the drawing method of the present invention, an exposure area in which a plurality of light modulation elements are arranged in a matrix and is an irradiation spot by a light modulation unit that irradiates light to be drawn onto a drawing object, and the light intensity distribution is substantially uniform, A drawing method for controlling a plurality of light modulation elements so as to form a pattern in accordance with the relative position of an exposure area on a drawing object by performing raster scanning on the drawing object. Is tilted with respect to the sub-scanning direction, and the exposure operation is executed while overlapping the exposure area along the main scanning direction, and the exposure area is overlapped along the sub-scanning direction. In the sub-scanning direction so that the cumulative exposure amount becomes equal along the sub-scanning direction in the overlap zone between adjacent exposure areas. And characterized in that the exposure area only relative movement a predetermined amount I.

  A drawing method having another feature of the present invention is an irradiation spot by a light modulation unit in which a plurality of light modulation elements are arranged in a matrix and irradiates light from a light source onto a drawing object, and the light intensity distribution is substantially uniform. A drawing method for controlling a plurality of light modulation elements so as to form a pattern in accordance with a relative position of an exposure area on a drawing object by raster scanning a to-be-drawn object with respect to the drawing object. The exposure operation is executed while overlapping the exposure area along the direction of the light, and the exposure area is relatively moved along the sub-scanning direction so that the exposure area overlaps along the sub-scanning direction. Make the area perpendicular to the sub-scanning direction so that the outline of the exposure area is inclined, and in the overlap zone between adjacent exposure areas. Amount to be equal in the sub-scanning direction, and wherein the defining an effective exposure area of the light modulation unit according to the relative amount of movement along the sub-scanning direction of the exposure area.

  The scanning device according to the present invention is an irradiation spot by a light modulation unit that irradiates light to a drawing object with a stage in which a drawing object is supported and a plurality of light modulation elements are arranged in a matrix and has light intensity. Scanning means for raster-scanning the object to be drawn by moving the stage, and an irradiation area of the entire light modulation unit is inclined with respect to the sub-scanning direction. The exposure area is relatively moved along the sub-scanning direction so that the exposure areas overlap along the scanning direction, and the scanning means has a cumulative exposure amount along the sub-scanning direction in the overlap zone between adjacent exposure areas. The exposure area is relatively moved by a predetermined amount along the sub-scanning direction so as to be equal to each other.

  The exposure control apparatus according to the present invention is an irradiation spot by a light modulation unit that irradiates light to be drawn on a drawing object by converting a pattern data into raster data and a plurality of light modulation elements arranged in a matrix. Exposure control means for controlling a plurality of light modulation elements so as to form a pattern in accordance with the relative position of the drawing object in the exposure area having a substantially uniform light intensity distribution, and the exposure control means comprises main scanning. The exposure operation is performed while overlapping the exposure area along the direction, and the exposure control means makes the cumulative exposure amount so that the outline of the exposure area is inclined, and in the overlap zone between the adjacent exposure areas. The effective exposure area of the light modulation unit is defined according to the relative movement amount of the exposure area along the sub-scanning direction so as to be equal along the sub-scanning direction. To.

  The program of the present invention is an irradiation spot by a light modulation unit that irradiates light to be drawn with a conversion means for converting pattern data into raster data and a plurality of light modulation elements arranged in a matrix. A program for functioning an exposure control means for controlling a plurality of light modulation elements so as to form a pattern in accordance with a relative position on an object to be drawn in an exposure area having a substantially uniform light intensity distribution. The exposure control means functions so that the exposure operation is executed while overlapping the exposure area along the exposure area so that the outline of the exposure area is inclined, and the cumulative exposure is performed in the overlap zone between the adjacent exposure areas. The effective exposure of the light modulation unit according to the amount of relative movement along the sub-scanning direction of the exposure area so that the amount is equal along the sub-scanning direction To define the frequency, characterized in that the functioning of the exposure control means.

  In the substrate manufacturing method of the present invention, 1) a photosensitive material is applied to a substrate that is a blank, 2) a drawing process is performed on the applied substrate, and 3) a development process is performed on the drawn substrate. And 4) a substrate manufacturing method in which etching processing is performed on the developed substrate, and 5) the photosensitive material is peeled off on the etched or plated substrate, and a plurality of drawing processes are performed. The light modulation elements are arranged in a matrix, and the object to be drawn is subjected to raster scanning on an exposure area that is an irradiation spot by a light modulation unit that irradiates the object to be drawn with light from a light source and has a substantially uniform light intensity distribution. The plurality of light modulation elements are controlled so that a pattern is formed according to the relative position of the exposure area on the object to be drawn, and the irradiation area of the entire light modulation unit is inclined with respect to the sub-scanning direction. The exposure operation is executed while overlapping the exposure areas along the direction, and the exposure areas are relatively moved along the sub-scanning direction so that the exposure areas overlap along the sub-scanning direction. In this overlap zone, the exposure area is relatively moved by a predetermined amount along the sub-scanning direction so that the cumulative exposure amount becomes equal along the sub-scanning direction.

  According to another aspect of the present invention, there is provided a substrate manufacturing method comprising: 1) applying a photosensitive material to a blank substrate; 2) executing a drawing process on the applied substrate; and 3) applying the drawing process to the substrate. 4) A substrate manufacturing method in which a development process is performed, 4) an etching process is performed on the developed substrate, and 5) a photosensitive material is peeled off from the etched or plated substrate. In the processing, a plurality of light modulation elements are arranged in a matrix, and an exposure area by the light modulation unit that irradiates the object to be drawn with light from the light source and having an approximately uniform light intensity distribution on the object to be drawn. The plurality of light modulation elements are controlled so as to form a pattern according to the relative position of the exposure area on the drawing object, and the exposure area is overlapped along the main scanning direction. The operation is executed, the exposure area is relatively moved along the sub-scanning direction so that the exposure areas overlap along the sub-scanning direction, and the irradiation area by the entire light modulation unit is orthogonalized along the sub-scanning direction, Relative movement of the exposure area along the sub-scanning direction so that the contour of the exposure area is inclined and the cumulative exposure amount is equal along the sub-scanning direction in the overlap zone between adjacent exposure areas The effective exposure area of the light modulation unit is defined according to the quantity.

  According to the present invention, a fine pattern can be formed with high precision in a drawing process by raster scanning using a light modulation unit.

  Hereinafter, a drawing apparatus according to an embodiment of the present invention will be described with reference to the drawings.

  FIG. 1 is a perspective view schematically showing a drawing apparatus according to the first embodiment. FIG. 2 is a diagram schematically showing an exposure unit provided in the drawing apparatus.

  The drawing device 10 is a device that forms a circuit pattern by irradiating light onto a substrate coated with a photosensitive material such as a photoresist, and includes a gate-like structure 12 and a base 14. An XY stage drive mechanism 19 that supports an XY stage 18 is mounted on the base 14, and a substrate SW is installed on the XY stage 18. The gate-like structure 12 is provided with an exposure unit 20 for forming a circuit pattern on the surface of the substrate SW, and the exposure unit 20 operates in accordance with the movement of the XY stage 18. Further, the drawing apparatus 10 includes a drawing control unit (not shown here) that controls the movement of the XY stage 18 and the operation of the exposure unit 20. The substrate SW is, for example, a silicon wafer, a copper-clad laminate, a film, or a glass substrate, and is mounted on the XY stage 18 in a blank state that has been subjected to processing such as pre-pag processing and photoresist coating.

  As shown in FIG. 2, the exposure unit 20 includes a light source 21, a DMD (Digital Micro-mirror Device) 22, an illumination optical system 24, and an imaging optical system 26, and illumination optics between the light source 21 and the DMD 22. A system 24 is disposed, and an imaging optical system 26 is disposed between the DMD 22 and the substrate SW. Light (beam) continuously emitted from the light source 21 with a constant intensity is guided to the illumination optical system 24. The illumination optical system 24 includes a diffusion plate 24A and a collimator lens 24B. When the beam LB passes through the illumination optical system 24, light composed of a light beam that totally illuminates the DMD 22 is formed.

The DMD 22 is a light modulation unit in which minute micromirrors having an order of μm are arranged in a matrix, and each micromirror rotates and fluctuates due to an electrostatic field effect. In the present embodiment, the DMD 22 is configured by arranging M × N micromirrors in a matrix. In the following description, a micromirror corresponding to the position of the array (i, j) is designated as “X _ij ” (1 ≦ i ≦ M, 1 ≦ j ≦ N). For example, the DMD 22 is configured by a 1024 × 768 micromirror. As will be described later, the DMD 22 is positioned in an inclined state with respect to the moving direction of the XY stage 18.

The micromirror X _ij is positioned in one of the first posture for reflecting the beam LB from the light source 21 in the direction of the exposure surface SU of the substrate SW and the second posture for reflecting the beam LB in the direction outside the exposure surface SU. The posture is switched in accordance with a control signal from the drawing control unit. When the micromirror X _ij is positioned in the first posture, the light reflected on the micromirror X _ij is guided toward the imaging optical system 26. The imaging optical system 26 schematically shown includes two convex lenses and a reflector lens (not shown), and light passing through the imaging optical system 26 is an exposure surface on which a photoresist layer is formed. Irradiate a predetermined area of the SU.

On the other hand, when the micro mirror X _ij is positioned in the second posture, the light reflected by the micro mirror X _ij is guided in the direction of the light absorbing plate (not shown), and the exposure surface SU is not irradiated with light. Hereinafter, the state in which the micromirror X _ij is supported in the first posture is defined as the ON state, and the state in which the micromirror X _ij is supported in the second posture is defined as the OFF state.

Here, the magnification of the imaging optical system 26 is set to 1 ×, and the size (width, height) of the irradiation spot Y _ij by one micromirror X _ij matches the size of the micromirror X _ij . When the height corresponding to the sub-scanning direction (Y direction) of the micromirror X _ij is represented by h and the width corresponding to the scanning direction (X direction) is represented by l, an irradiation spot Y _ij having a size of h × l (hereinafter, referred to as “h”). Is called a microspot). Here, the micromirror X _ij has a square shape (h = 1). Further, the size of the micromirror X _ij is very small with respect to the line width of the pattern, and the length of each micromirror, that is, a small spot is set to several to several tens of μm. The size of the DMD 22 is determined in accordance with a television display standard. The direction corresponding to the scanning direction of the DMD 22 is defined as the horizontal direction, the direction corresponding to the sub-scanning direction is defined as the vertical direction, and the width (lateral length) and When the height (length in the vertical direction) is represented by “W” and “K”, respectively, the aspect ratio (aspect ratio W: K) of the DMD 22 is set to 3: 4 here.

When all the micromirrors are in the ON state with the XY stage 18 stopped, a spot EA having a predetermined size hits the exposure surface SU (hereinafter, this spot area is referred to as an exposure area). Since the magnification of the imaging optical system 26 is 1, the relationship of D × R = K × W (= (M × h) × (N × l)) is established. The light intensity distribution in the exposure area EA is substantially uniform in that area, and the light source 21, the imaging optical system 26, and the illumination optical system 24 are configured so that the light intensity distribution is uniform. In the DMD 22, the micromirrors X _ij are independently turned on / off, so that the light irradiated on the entire DMD 22 is divided into light composed of light beams selectively reflected by the micromirrors. The As a result, light corresponding to the circuit pattern to be formed at the place is irradiated on an arbitrary area Ew where the exposure area EA is located on the exposure surface SU. According to the raster scanning, the XY stage 18 moves at a constant speed, and accordingly, the exposure area EA moves on the exposure surface SU along the main scanning direction (X direction) at a relatively constant speed. Are formed along the main scanning direction (X direction).

During the relative movement of the exposure area EA, as described later, the exposure operation is repeatedly performed so that the exposure areas EA overlap each other, that is, the micro spots Y _ij of the micromirrors X _ij overlap each other. When scanning for one scanning band is completed, the XY stage 18 moves relative to the sub scanning direction (Y direction) so that the next scanning band can be exposed, and the folded XY stage 18 moves along the scanning direction. To do. However, a passing region along the main scanning direction (X direction) of the exposure area is defined as a scanning band. When the XY stage 18 continuously moves and the exposure operation is performed over all scanning bands, a circuit pattern is formed on the substrate SW.

  When scanning for one band is completed, the XY stage 18 moves a predetermined distance in the Y direction (sub-scanning direction), and the next scanning band is relatively moved. When all the scanning bands are scanned while the exposure area EA reciprocates, the drawing process is completed. After the drawing processing, development processing, etching or plating, resist stripping processing, and the like are performed to manufacture a substrate on which a circuit pattern is formed.

  FIG. 3 is a block diagram of the drawing apparatus.

  The drawing control unit 30 includes a system control circuit 32, a DMD control unit 34, a stage control unit 38, a stage position detection unit 40, a raster conversion unit 42, and a light source control unit 44. The system control includes a CPU, RAM, ROM, and the like. The circuit 32 controls the entire drawing apparatus 10, and the DMD control unit 34 controls the DMD 22 in accordance with a drawing processing program stored in advance in the ROM.

  When circuit pattern data corresponding to the drawing apparatus 10 is sent as CAM data (vector data) from a workstation (not shown) to the raster conversion unit 42 of the drawing control unit 30, the pattern data is converted into raster data corresponding to raster scanning. It is converted and temporarily stored in the bitmap memory 43 of the DMD control unit 34. The raster data is binary data indicating whether the micromirror is on or off, and is represented as a two-dimensional dot pattern of a circuit pattern.

  The raster data stored in the bitmap memory 43 is sequentially read at a predetermined timing according to the relative position of the exposure area EA. Based on the read bitmap data and the relative position information of the exposure area EA sent from the stage position detector 40, a control signal for ON / OFF control of the micromirror is output to the DMD 22. The stage control unit 38 controls an XY stage driving mechanism 19 having a motor (not shown), and thereby the moving speed of the XY stage 18 is controlled. The stage position detector 40 detects the relative position of the exposure area EA with respect to the XY stage 18. The system control circuit 32 sends a control signal to the light source control unit 44 to emit light from the light source 21 and outputs a control signal for controlling the exposure timing to the DMD control unit 34.

  FIG. 4 is a diagram showing relative movement of the exposure area EA, that is, scanning by the exposure area EA. FIG. 5 is a diagram showing the central projection plot distribution of the micromirror when performing exposure in the region corresponding to the minute spot on the drawing surface. FIG. 6 is a graph showing a cumulative exposure amount graph. The exposure operation and the exposure amount will be described with reference to FIGS.

  The DMD 22 is installed such that the exposure area EA (D × R) is inclined by a predetermined angle α with respect to the sub-scanning direction (Y direction), and the exposure area EA is inclined in the main scanning direction (X direction). The relative movement is made (see FIG. 4). The angle α is determined so that the diagonal line connecting the vertices A2 and A4 of the exposure area EA is parallel to the main scanning direction (X direction). Here, it is assumed that all the micromirrors of the DMD 22 perform an exposure operation, that is, irradiate the substrate SW with light.

FIG. 5 shows a projection plot of the center position of the micromirror while the exposure area EA is relatively moving on the exposure surface SU. While the XY stage 18 moves at a constant speed, each micromirror performs an exposure operation at predetermined time intervals. That is, the micromirror X _ij is controlled to be switched ON / OFF at a predetermined time interval, and the substrate SW is irradiated with light at a predetermined time interval. In order to repeatedly expose the minute spots while overlapping each other, a minute area (hereinafter, referred to as a minute drawing surface area) AR on the drawing surface corresponding to the width l of the minute spot Y _ij of the micromirror X _ij AR The exposure operation is performed at a time interval shorter than the time during which the exposure area EA moves.

Since the micromirrors are arranged in a matrix during the relative movement of the exposure area EA, the microscopic spots of the micromirrors successively hit the predetermined microscopic drawing area AR. However, since the exposure area EA is inclined with respect to the main scanning direction (X direction) and the arrangement direction of the micromirrors X _ij , that is, the arrangement direction of the minute spots is not parallel to the main scanning direction, The minute spots formed by a large number of micromirrors overlap each other while being slightly shifted from each other in the main scanning direction (X direction) and the sub-scanning direction (Y direction). The projection plot shown in FIG. 5 is a projection plot of the center position of the micromirror in accordance with the time interval of the exposure operation, and the center projection plot is distributed substantially uniformly after scanning for one scanning band. However, FIG. 5 shows only a part of the projection plot, and the projection plot is actually substantially uniformly distributed in the minute drawing surface area AR.

  When the exposure area EA that relatively moves along the main scanning direction (X direction) reaches the end of the substrate SW, the XY stage 18 moves by a predetermined distance RH along the sub scanning direction (Y direction), and exposure is performed. Area EA moves in the sub-scanning direction by a relative distance RH. The distance RH is the length from the vertices A2 and A4 of the exposure area EA to the vertices A1 and A3 along the sub-scanning direction (Y direction), and is 1 / of the scanning bandwidth RB defined according to the inclined exposure area EA. It corresponds to 2. Therefore, after the exposure area EA is moved in the sub-scanning direction, the vertices A2 and A4 of the exposure area EA move on the line scanned by the vertex A3.

  When the position of the exposure area EA moves by the distance RH, the exposure area EA moves in the opposite direction along the main scanning direction. When the rectangular exposure area EA is divided into an upper exposure area EA1 and a lower exposure area EA2 along a diagonal line passing through the vertices A2 and A4, the upper exposure area EA1 and the lower exposure area EA2 pass through the same area with a time difference. Therefore, all areas on the substrate SW are overlap areas. As a result, such scanning by the exposure area EA is continued according to the continuous movement method of the XY stage.

  FIG. 6 shows the cumulative exposure amount along one scanning bandwidth RB along the sub-scanning direction. However, the cumulative exposure amount represents the total exposure amount when all the micromirrors are exposed. The cumulative exposure amount of the scanning band SB1 becomes maximum in the scanning line passing through the diagonal lines A2 and A4, and decreases toward the vertexes A1 and A3. 6 shows the cumulative exposure amount along the sub-scanning direction (Y direction) with reference to the scanning line LR in FIG.

  When the exposure area EA moves in the scanning band SB1, the cumulative exposure amount of the overlap area OA by the lower exposure area EA2 is substantially represented by the straight line L1. Since the lower exposure area EA2 always moves ahead of the unexposed area, and the bottom of the triangular lower exposure area EA2 is at the scanning line LR at this time, it accumulates as the distance from the scanning line LR increases. The target exposure amount is small, and the distance from the scanning line LR and the exposure amount are substantially proportional to each other. This is because the cumulative exposure amount along an arbitrary scanning line is affected by the length of the exposure area EA along the scanning line, that is, the number of micromirrors arranged. On the other hand, the exposure area EA moves in the sub-scanning direction by RH, the exposure area EA moves in the scanning bands SB1 and SB2, that is, the upper exposure area EA1 moves in the scanning band SB1, and the lower exposure area EA2 moves in the scanning band. When SB2 is moved, the cumulative exposure amount by the upper exposure area EA1 is represented by a straight line L2. Since the upper exposure area EA1 moves so as to overlap the area through which the lower exposure area EA2 has passed, and since the apex of the triangular upper exposure area EA1 is on the scanning line LR at this time, The closer the distance is, the smaller the exposure amount, and the distance from the scanning line LR and the exposure amount are substantially proportional.

  The cumulative exposure amount in the overlap area OA when the exposure area EA moves in the scan band SB1 and the cumulative exposure amount in the overlap area OA when the exposure area EA moves in the scan band SB2 are correlated. The total exposure amount L3 obtained by adding the two cumulative exposure amounts is substantially constant. Therefore, the cumulative exposure amount in the overlap area OA is equal. As described above, in all the overlap areas OA, the exposure area upper part EA2 and the exposure area EA1 pass through the overlap area OA in order, so that the cumulative exposure amount is equal on the entire drawing surface.

  As described above, according to the present embodiment, overlap exposure is executed according to the continuous movement method and raster scanning in a situation where the intensity distribution of light irradiated to the exposure area EA is substantially equal. At this time, the DMD 22 is arranged so that the exposure area EA is inclined by a predetermined angle α with respect to the sub-scanning direction, and the angle α is set so that the diagonal line of the exposure area EA is parallel to the main scanning direction (X direction). The exposure area EA moves along the sub-scanning direction by a distance RH that is half the scanning bandwidth RB. Thereby, the cumulative exposure amount in the overlap area OA becomes substantially equal, and the pattern is formed with high accuracy.

  The exposure area EA moves along the sub-scanning direction by a distance RH that is half of the scanning bandwidth RB. The exposure area EA is not separated into an overlap area and an area that is not, and the entire drawing surface becomes an overlap area. As a result, there is no difference in the pattern line width of the joint portion caused by the time difference in the exposure operation, i.e., since all are overlap regions, the chemical reaction of the resist becomes equal along the sub-scanning direction. The line width of the pattern extending along the scanning direction can be accurately aligned.

  An image rotator or the like may be interposed between the light modulation unit and the substrate, and the exposure area may be inclined with respect to the scanning direction regardless of the arrangement direction of the light modulation units. The exposure area is not limited to a rectangular shape, and there are at least two vertices in the exposure area EA, and two partial areas (upper area and lower area) defined by the division of the line connecting the vertices are in a mirror image relationship or a line The exposure area EA may be defined so as to have a symmetrical relationship.

  Instead of the movement by the XY stage 18, the DMD may be moved relatively. In raster scanning, a plurality of DMDs 22 may be arranged and scanned at predetermined intervals. In the overlap exposure along the main scanning direction, the XY stage 18 may be moved intermittently.

  Next, a drawing apparatus according to the second embodiment will be described with reference to FIGS. In the second embodiment, unlike the first embodiment, the exposure area is not inclined with respect to the sub-scanning direction (sub-scanning direction), and the region actually used among the plurality of micromirrors is defined. . About another structure, it is the same as 1st Embodiment.

  FIG. 7 is a diagram showing scanning by the exposure area in the second embodiment. FIG. 8 is a diagram showing the light modulation unit.

  As shown in FIG. 8, in the light modulation unit 22, an exposure operation is performed, that is, an effective exposure region 22A in which the micromirror is controlled to be switched on / off at a predetermined time interval, and non-exposure in which the micromirror is always set to an OFF state. A region 22B is defined. The pattern data sent from the workstation incorporates data indicating the ON state according to the pattern for the micromirror located in the non-exposure area 22B. Regardless of this data, the DMD control unit 34 controls the DMD 22 so as not to perform the exposure operation on the micromirrors in the non-exposure region 22B. The effective exposure area 22A is defined as an isosceles triangle, and the shape of the effective exposure area 22A is determined in accordance with the exposure area EA 'shown in FIG.

  The exposure area E0 when all the micromirrors are usable is not inclined with respect to the sub-scanning direction (main scanning direction), and is an irradiation area by the effective exposure region 22A (in the second embodiment, the exposure area and the exposure area). The vertex A4 of EA ′ is located on the scanning line LR that bisects the width RB of the scanning band SB. The cumulative exposure amounts of the upper exposure area EA1 'and the lower exposure area EA2' of the exposure area EA 'also have a correlation as shown in FIG. Therefore, the cumulative exposure amount of the overlap area OA is equal for each scan line.

  FIG. 9 is a diagram showing a modification of the effective exposure area. The effective exposure region 22C is defined as an isosceles triangle, and the bisector is parallel to the main scanning direction. The effective exposure areas 22D and 22E are defined as parallelograms, and the diagonal lines are parallel along the main scanning direction. Further, the effective exposure area 22F is defined as a rhombus. Even with such an effective exposure area, the cumulative exposure amount of the overlap area OA becomes equal. The exposure area E0 does not have to be orthogonal to the sub-scanning direction, and the irradiation area by the effective exposure region only needs to have the shape shown in FIGS.

It is the perspective view which showed typically the drawing apparatus which is 1st Embodiment. It is the figure which showed typically the exposure unit provided in the drawing apparatus. It is a block diagram of a drawing apparatus. It is the figure which showed the scanning by an exposure area. It is the figure which showed the center projection plot distribution of the micromirror at the time of execution of exposure in the area | region according to the micro spot on the drawing surface. It is the figure which showed the graph of the cumulative exposure amount. It is the figure which showed the scanning by the exposure area in 2nd Embodiment. It is the figure which showed the light modulation unit. It is the figure which showed the modification of the effective exposure area | region.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Drawing apparatus 18 XY stage 21 Light source 22 DMD (light modulation unit)
22A Effective exposure area 22B Non-exposure area 24 Illumination optical system 30 Drawing controller 32 System control circuit EA Exposure area SW Substrate X _ij micromirror Y _ij micro spot SB Scan band OA Overlap area α Inclination angle X Main scanning direction Y Sub scanning direction

Claims (5)

A light source;
A plurality of light modulation elements arranged in a matrix, a light modulation unit that modulates light from the light source and irradiates the drawing object with light; and
Scanning means for raster-scanning the drawing object with respect to an exposure area that is an irradiation spot by the light modulation unit and has a substantially uniform light intensity distribution;
Exposure control means for controlling the plurality of light modulation elements so as to form a pattern according to the relative position of the exposure area on the drawing object;
The irradiation area by the entire light modulation unit is inclined with respect to the sub-scanning direction,
The exposure control means causes the exposure operation to be performed while overlapping the exposure areas along the main scanning direction, and the scanning means performs the exposure area so that the exposure areas overlap along the sub-scanning direction. Relative movement along the sub-scanning direction,
The scanning means relatively moves the exposure area by a predetermined amount along the sub-scanning direction so that the cumulative exposure amount becomes equal along the sub-scanning direction in an overlap zone between adjacent exposure areas;
The exposure area is rectangular,
The drawing apparatus, wherein the exposure area is inclined with respect to the sub-scanning direction so that diagonal lines of the exposure area are parallel along the main scanning direction.   The drawing apparatus according to claim 1, wherein the scanning unit raster scans the exposure area according to a continuous movement method. A plurality of light modulation elements are arranged in a matrix, and an exposure area that is an irradiation spot by a light modulation unit that irradiates the object to be drawn with light from a light source and has a substantially uniform light intensity distribution with respect to the object to be drawn Raster scan,
A drawing method for controlling the plurality of light modulation elements so as to form a pattern according to a relative position of the exposure area on the drawing object,
Inclining the irradiation area by the entire light modulation unit with respect to the sub-scanning direction,
The exposure operation is performed while overlapping the exposure area along the main scanning direction, and the exposure area is relatively moved along the sub scanning direction so that the exposure area overlaps along the sub scanning direction,
Relatively moving the exposure area by a predetermined amount along the sub-scanning direction so that the cumulative exposure amount becomes equal along the sub-scanning direction in an overlap zone between adjacent exposure areas;
The exposure area is rectangular,
The drawing method, wherein the exposure area is inclined with respect to the sub-scanning direction so that diagonal lines of the exposure area are parallel to each other along the main scanning direction. A stage that supports the drawing object;
A plurality of light modulation elements are arranged in a matrix, and an exposure area by a light modulation unit that irradiates the object to be drawn with light from a light source and having a substantially uniform light intensity distribution is moved by moving the stage. Scanning means for raster-scanning the object to be drawn,
The irradiation area by the entire light modulation unit is inclined with respect to the sub-scanning direction,
The scanning means relatively moves the exposure area along the sub-scanning direction so that the exposure area overlaps along the sub-scanning direction;
The scanning means relatively moves the exposure area by a predetermined amount along the sub-scanning direction so that the cumulative exposure amount becomes equal along the sub-scanning direction in an overlap zone between adjacent exposure areas;
The exposure area is rectangular,
The scanning apparatus, wherein the exposure area is inclined with respect to the sub-scanning direction so that diagonal lines of the exposure area are parallel to each other along the main scanning direction. 1) Apply a photosensitive material to the substrate, which is a blank,
2) Perform a drawing process on the coated substrate,
3) Develop the substrate that has been subjected to the drawing process,
4) Etching or plating the developed substrate,
5) A method for manufacturing a substrate in which a photosensitive material is peeled from an etched or plated substrate,
In the drawing process,
A plurality of light modulation elements are arranged in a matrix, and an exposure area that is an irradiation spot by a light modulation unit that irradiates the object to be drawn with light from a light source and has a substantially uniform light intensity distribution with respect to the object to be drawn Raster scan,
A drawing process for controlling the plurality of light modulation elements so as to form a pattern according to a relative position of the exposure area in the drawing object;
Inclining the irradiation area by the entire light modulation unit with respect to the sub-scanning direction,
The exposure operation is performed while overlapping the exposure area along the main scanning direction, and the exposure area is relatively moved along the sub scanning direction so that the exposure area overlaps along the sub scanning direction,
Relatively moving the exposure area by a predetermined amount along the sub-scanning direction so that the cumulative exposure amount becomes equal along the sub-scanning direction in an overlap zone between adjacent exposure areas;
The exposure area is rectangular,
The substrate manufacturing method, wherein the exposure area is inclined with respect to the sub-scanning direction so that diagonal lines of the exposure area are parallel to each other along the main scanning direction.

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